TY - JOUR A1 - Langhauser, Friederike A1 - Casas, Ana I. A1 - Dao, Vu-Thao-Vi A1 - Guney, Emre A1 - Menche, Jörg A1 - Geuss, Eva A1 - Kleikers, Pamela W. M. A1 - López, Manuela G. A1 - Barabási, Albert-L. A1 - Kleinschnitz, Christoph A1 - Schmidt, Harald H. H. W. T1 - A diseasome cluster-based drug repurposing of soluble guanylate cyclase activators from smooth muscle relaxation to direct neuroprotection JF - npj Systems Biology and Applications N2 - Network medicine utilizes common genetic origins, markers and co-morbidities to uncover mechanistic links between diseases. These links can be summarized in the diseasome, a comprehensive network of disease–disease relationships and clusters. The diseasome has been influential during the past decade, although most of its links are not followed up experimentally. Here, we investigate a high prevalence unmet medical need cluster of disease phenotypes linked to cyclic GMP. Hitherto, the central cGMP-forming enzyme, soluble guanylate cyclase (sGC), has been targeted pharmacologically exclusively for smooth muscle modulation in cardiology and pulmonology. Here, we examine the disease associations of sGC in a non-hypothesis based manner in order to identify possibly previously unrecognized clinical indications. Surprisingly, we find that sGC, is closest linked to neurological disorders, an application that has so far not been explored clinically. Indeed, when investigating the neurological indication of this cluster with the highest unmet medical need, ischemic stroke, pre-clinically we find that sGC activity is virtually absent post-stroke. Conversely, a heme-free form of sGC, apo-sGC, was now the predominant isoform suggesting it may be a mechanism-based target in stroke. Indeed, this repurposing hypothesis could be validated experimentally in vivo as specific activators of apo-sGC were directly neuroprotective, reduced infarct size and increased survival. Thus, common mechanism clusters of the diseasome allow direct drug repurposing across previously unrelated disease phenotypes redefining them in a mechanism-based manner. Specifically, our example of repurposing apo-sGC activators for ischemic stroke should be urgently validated clinically as a possible first-in-class neuroprotective therapy. KW - neurology KW - pharmacology KW - systems biology Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236381 VL - 4 ER - TY - JOUR A1 - Wong, Alex H. K. A1 - Pittig, Andre T1 - A dimensional measure of safety behavior: A non-dichotomous assessment of costly avoidance in human fear conditioning JF - Psychological Research N2 - Safety behavior prevents the occurrence of threat, thus it is typically considered adaptive. However, safety behavior in anxiety-related disorders is often costly, and persists even the situation does not entail realistic threat. Individuals can engage in safety behavior to varying extents, however, these behaviors are typically measured dichotomously (i.e., to execute or not). To better understand the nuances of safety behavior, this study developed a dimensional measure of safety behavior that had a negative linear relationship with the admission of an aversive outcome. In two experiments, a Reward group receiving fixed or individually calibrated incentives competing with safety behavior showed reduced safety behavior than a Control group receiving no incentives. This allowed extinction learning to a previously learnt warning signal in the Reward group (i.e., updating the belief that this stimulus no longer signals threat). Despite the Reward group exhibited extinction learning, both groups showed a similar increase in fear to the warning signal once safety behavior was no longer available. This null group difference was due to some participants in the Reward group not incentivized enough to disengage from safety behavior. Dimensional assessment revealed a dissociation between low fear but substantial safety behavior to a safety signal in the Control group. This suggests that low-cost safety behavior does not accurately reflect the fear-driven processes, but also other non-fear-driven processes, such as cost (i.e., engage in safety behavior merely because it bears little to no cost). Pinpointing both processes is important for furthering the understanding of safety behavior. KW - safety behavior KW - anxiety KW - threat Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-267688 SN - 1430-2772 VL - 86 IS - 1 ER - TY - JOUR A1 - Bayer, Daniel A1 - Pruckner, Marco T1 - A digital twin of a local energy system based on real smart meter data JF - Energy Informatics N2 - The steadily increasing usage of smart meters generates a valuable amount of high-resolution data about the individual energy consumption and production of local energy systems. Private households install more and more photovoltaic systems, battery storage and big consumers like heat pumps. Thus, our vision is to augment these collected smart meter time series of a complete system (e.g., a city, town or complex institutions like airports) with simulatively added previously named components. We, therefore, propose a novel digital twin of such an energy system based solely on a complete set of smart meter data including additional building data. Based on the additional geospatial data, the twin is intended to represent the addition of the abovementioned components as realistically as possible. Outputs of the twin can be used as a decision support for either system operators where to strengthen the system or for individual households where and how to install photovoltaic systems and batteries. Meanwhile, the first local energy system operators had such smart meter data of almost all residential consumers for several years. We acquire those of an exemplary operator and discuss a case study presenting some features of our digital twin and highlighting the value of the combination of smart meter and geospatial data. KW - digital twin KW - simulation KW - local energy system KW - decision support system KW - smart meter data utilization KW - future energy grid exploration Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357456 VL - 6 ER - TY - JOUR A1 - Müller, Frank A1 - Chandra, Shivani A1 - Furaijat, Ghefar A1 - Kruse, Stefan A1 - Waligorski, Alexandra A1 - Simmenroth, Anne A1 - Kleinert, Evelyn T1 - A digital communication assistance tool (DCAT) to obtain medical history from foreign-language patients: development and pilot testing in a primary health care center for refugees JF - International Journal of Environmental Research and Public Health N2 - Background: Language barriers play a critical role in the treatment of migrant and refugee patients. In Germany, primary care interpreters are often not available especially in rural areas or if patients demand spontaneous or urgent consultations. Methods: In order to enable patients and their physicians to communicate effectively about the current illness history, we developed a digital communication assistance tool (DCAT) for 19 different languages and dialects. This paper reports the multidisciplinary process of the conceptual design and the iterative development of this cross-cultural user-centered application in an action-oriented approach. Results: We piloted our app with 36 refugee patients prior to a clinical study and used the results for further development. The acceptance and usability of the app by patients was high. Conclusion: Using digital tools for overcoming language barriers can be a feasible approach when providing health care to foreign-language patients. KW - language barriers KW - app KW - interpreter KW - primary care KW - medical history taking KW - refugee KW - culturally and linguistically diverse patients Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200640 SN - 1660-4601 VL - 17 IS - 4 ER - TY - JOUR A1 - Seibel, Sebastian A1 - Volmer, Judith T1 - A Diary Study on Anticipated Leisure Time, Morning Recovery, and Employees’ Work Engagement JF - International Journal of Environmental Research and Public Health N2 - Recovery during yesterday’s leisure time is beneficial for morning recovery, and morning recovery fosters employees’ work engagement, a positive, motivational state associated with job performance. We extended existing research by assuming that both, morning recovery (considered a resource) and anticipated leisure time (considered an anticipated resource gain), relate to work engagement. Anticipated leisure time comprises two constructs: general anticipation of leisure time, which refers to employees’ cognitive evaluation of their entire upcoming leisure time, and pleasant anticipation of a planned leisure activity, which describes a positive affective reaction because of one specific, upcoming leisure activity. We suggested that employees with high pleasant anticipation generate more thoughts of a planned leisure activity (ToPLA), which may distract them from their work, reducing their work engagement. A diary study over five days showed that morning recovery and general anticipation of leisure time were positively related to work engagement. Furthermore, employees with higher pleasant anticipation of a planned leisure activity reported more ToPLA. In contrast to our expectations, neither pleasant anticipation nor ToPLA was related to work engagement. In sum, this study introduced anticipated leisure time as a novel antecedent of work engagement and demonstrated that anticipated resource gains are important for high work engagement. KW - morning recovery KW - leisure time KW - pleasant anticipation KW - work engagement KW - thoughts of a planned leisure activity KW - diary study Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246090 SN - 1660-4601 VL - 18 IS - 18 ER - TY - JOUR A1 - Bäuerlein, Carina A. A1 - Riedel, Simone S. A1 - Baker, Jeanette A1 - Brede, Christian A1 - Jordán Garrote, Ana-Laura A1 - Chopra, Martin A1 - Ritz, Miriam A1 - Beilhack, Georg F. A1 - Schulz, Stephan A1 - Zeiser, Robert A1 - Schlegel, Paul G. A1 - Einsele, Hermann A1 - Negrin, Robert S. A1 - Beilhack, Andreas T1 - A diagnostic window for the treatment of acute graft-versus-host disease prior to visible clinical symptoms in a murine model JF - BMC Medicine N2 - Background Acute graft-versus-host disease (aGVHD) poses a major limitation for broader therapeutic application of allogeneic hematopoietic cell transplantation (allo-HCT). Early diagnosis of aGVHD remains difficult and is based on clinical symptoms and histopathological evaluation of tissue biopsies. Thus, current aGVHD diagnosis is limited to patients with established disease manifestation. Therefore, for improved disease prevention it is important to develop predictive assays to identify patients at risk of developing aGVHD. Here we address whether insights into the timing of the aGVHD initiation and effector phases could allow for the detection of migrating alloreactive T cells before clinical aGVHD onset to permit for efficient therapeutic intervention. Methods Murine major histocompatibility complex (MHC) mismatched and minor histocompatibility antigen (miHAg) mismatched allo-HCT models were employed to assess the spatiotemporal distribution of donor T cells with flow cytometry and in vivo bioluminescence imaging (BLI). Daily flow cytometry analysis of peripheral blood mononuclear cells allowed us to identify migrating alloreactive T cells based on homing receptor expression profiles. Results We identified a time period of 2 weeks of massive alloreactive donor T cell migration in the blood after miHAg mismatch allo-HCT before clinical aGVHD symptoms appeared. Alloreactive T cells upregulated α4β7 integrin and P-selectin ligand during this migration phase. Consequently, targeted preemptive treatment with rapamycin, starting at the earliest detection time of alloreactive donor T cells in the peripheral blood, prevented lethal aGVHD. Conclusions Based on this data we propose a critical time frame prior to the onset of aGVHD symptoms to identify alloreactive T cells in the peripheral blood for timely and effective therapeutic intervention. KW - Allogeneic stem cell transplantation KW - Graft-versus-host disease KW - Minor histocompatibility antigen mismatch transplantation Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-96797 UR - http://www.biomedcentral.com/1741-7015/11/134 ER - TY - JOUR A1 - Schamel, Johannes T1 - A demographic perspective on the spatial behaviour of hikers in mountain areas: the example of Berchtesgaden National Park JF - eco.mont - Journal on Protected Mountain Areas Research and Management N2 - In Germany, as in many Western societies, demographic change will lead to a higher number of senior visitors to natural recreational areas and national parks. Given the high physiological requirements of many outdoor recreation activities, especially in mountain areas, it seems likely that demographic change will affect the spatial behaviour of national park visitors, which may pose a challenge to the management of these areas. With the help of GPS tracking and a standardized questionnaire (n=481), this study empirically investigates the spatial behaviour of demographic age brackets in Berchtesgaden National Park (NP) and the potential effects of demographic change on the use of the area. Cluster analysis revealed four activity types in the study area. More than half of the groups with visitors aged 60 and older belong to the activity type of Walker. KW - geography KW - demographic change KW - spatial behaviour KW - GPS tracking KW - outdoor recreation KW - Berchtesgaden NP Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172128 SN - 2073-1558 VL - 9 IS - Special issue ER - TY - JOUR A1 - Gessler, Manfred A1 - Thomas, G. H. A1 - Couillin, P. A1 - Junien, C. A1 - McGillivray, B. C. A1 - Hayden, M. A1 - Jaschek, G. A1 - Bruns, G. A. T1 - A deletion map of the WAGR region on chromosome II N2 - The WAGR (Wilms tumor, aniridia, genitourinary anomalies, and mental retardation) region has been assigned to chromosome 11p13 on the basis of overlapping constitutional deletions found in affected individuals. We have utilized 31 DNA probes which map to the WAGR deletion region, together with six reference loci and 13 WAGR-related deletions, to subdivide this area into 16 intervals. Specific intervals have been correlated with phenotypic features, leading to the identification of individual subregions for the aniridia and Wilms tumor loci. Delineation, by specific probes, of multiple intervals above and below the critical region and of five intervals within the overlap area provides a framework map for molecular characterization of WAGR gene loci and of deletion boundary regions. KW - Biochemie Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59255 ER - TY - JOUR A1 - Groll, J A1 - Burdick, J A A1 - Cho, D-W A1 - Derby, B A1 - Gelinsky, M A1 - Heilshorn, S C A1 - Jüngst, T A1 - Malda, J A1 - Mironov, V A A1 - Nakayama, K A1 - Ovsianikov, A A1 - Sun, W A1 - Takeuchi, S A1 - Yoo, J J A1 - Woodfield, T B F T1 - A definition of bioinks and their distinction from biomaterial inks JF - Biofabrication N2 - Biofabrication aims to fabricate biologically functional products through bioprinting or bioassembly (Groll et al 2016 Biofabrication 8 013001). In biofabrication processes, cells are positioned at defined coordinates in three-dimensional space using automated and computer controlled techniques (Moroni et al 2018 Trends Biotechnol. 36 384–402), usually with the aid of biomaterials that are either (i) directly processed with the cells as suspensions/dispersions, (ii) deposited simultaneously in a separate printing process, or (iii) used as a transient support material. Materials that are suited for biofabrication are often referred to as bioinks and have become an important area of research within the field. In view of this special issue on bioinks, we aim herein to briefly summarize the historic evolution of this term within the field of biofabrication. Furthermore, we propose a simple but general definition of bioinks, and clarify its distinction from biomaterial inks. KW - bioink KW - biomaterial ink KW - definition Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-253993 VL - 11 IS - 1 ER - TY - JOUR A1 - Sivarajan, Rinu A1 - Oberwinkler, Heike A1 - Roll, Valeria A1 - König, Eva-Maria A1 - Steinke, Maria A1 - Bodem, Jochen T1 - A defined anthocyanin mixture sourced from bilberry and black currant inhibits Measles virus and various herpesviruses JF - BMC Complementary Medicine and Therapies N2 - Background Anthocyanin-containing plant extracts and carotenoids, such as astaxanthin, have been well-known for their antiviral and anti-inflammatory activity, respectively. We hypothesised that a mixture of Ribes nigrum L. (Grossulariaceae) (common name black currant (BC)) and Vaccinium myrtillus L. (Ericaceae) (common name bilberry (BL)) extracts (BC/BL) with standardised anthocyanin content as well as single plant extracts interfered with the replication of Measles virus and Herpesviruses in vitro. Methods We treated cell cultures with BC/BL or defined single plant extracts, purified anthocyanins and astaxanthin in different concentrations and subsequently infected the cultures with the Measles virus (wild-type or vaccine strain Edmonston), Herpesvirus 1 or 8, or murine Cytomegalovirus. Then, we analysed the number of infected cells and viral infectivity and compared the data to non-treated controls. Results The BC/BL extract inhibited wild-type Measles virus replication, syncytia formation and cell-to-cell spread. This suppression was dependent on the wild-type virus-receptor-interaction since the Measles vaccine strain was unaffected by BC/BL treatment. Furthermore, the evidence was provided that the delphinidin-3-rutinoside chloride, a component of BC/BL, and purified astaxanthin, were effective anti-Measles virus compounds. Human Herpesvirus 1 and murine Cytomegalovirus replication was inhibited by BC/BL, single bilberry or black currant extracts, and the BC/BL component delphinidin-3-glucoside chloride. Additionally, we observed that BC/BL seemed to act synergistically with aciclovir. Moreover, BC/BL, the single bilberry and black currant extracts, and the BC/BL components delphinidin-3-glucoside chloride, cyanidin-3-glucoside, delphinidin-3-rutinoside chloride, and petunidin-3-galactoside inhibited human Herpesvirus 8 replication. Conclusions Our data indicate that Measles viruses and Herpesviruses are differentially susceptible to a specific BC/BL mixture, single plant extracts, purified anthocyanins and astaxanthin. These compounds might be used in the prevention of viral diseases and in addition to direct-acting antivirals, such as aciclovir. KW - anthocyanin KW - astaxanthin KW - bilberry KW - black currant KW - herpesvirus KW - measels virus Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301423 VL - 22 ER - TY - JOUR A1 - Wech, Tobias A1 - Ankenbrand, Markus Johannes A1 - Bley, Thorsten Alexander A1 - Heidenreich, Julius Frederik T1 - A data-driven semantic segmentation model for direct cardiac functional analysis based on undersampled radial MR cine series JF - Magnetic Resonance in Medicine N2 - Purpose Image acquisition and subsequent manual analysis of cardiac cine MRI is time-consuming. The purpose of this study was to train and evaluate a 3D artificial neural network for semantic segmentation of radially undersampled cardiac MRI to accelerate both scan time and postprocessing. Methods A database of Cartesian short-axis MR images of the heart (148,500 images, 484 examinations) was assembled from an openly accessible database and radial undersampling was simulated. A 3D U-Net architecture was pretrained for segmentation of undersampled spatiotemporal cine MRI. Transfer learning was then performed using samples from a second database, comprising 108 non-Cartesian radial cine series of the midventricular myocardium to optimize the performance for authentic data. The performance was evaluated for different levels of undersampling by the Dice similarity coefficient (DSC) with respect to reference labels, as well as by deriving ventricular volumes and myocardial masses. Results Without transfer learning, the pretrained model performed moderately on true radial data [maximum number of projections tested, P = 196; DSC = 0.87 (left ventricle), DSC = 0.76 (myocardium), and DSC =0.64 (right ventricle)]. After transfer learning with authentic data, the predictions achieved human level even for high undersampling rates (P = 33, DSC = 0.95, 0.87, and 0.93) without significant difference compared with segmentations derived from fully sampled data. Conclusion A 3D U-Net architecture can be used for semantic segmentation of radially undersampled cine acquisitions, achieving a performance comparable with human experts in fully sampled data. This approach can jointly accelerate time-consuming cine image acquisition and cumbersome manual image analysis. KW - undersampling KW - cardiovascular magnetic resonance (CMR) KW - deep learning KW - radial KW - semantic segmentation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257616 VL - 87 IS - 2 ER - TY - CHAP A1 - Bezan, Sarah T1 - A Darwinism of the Muck and Mire: Decomposing the Eco- and Zoopoetics of Stephen Collis’ and Jordan Scott’s decomp T2 - Texts, Animals, Environments: Zoopoetics and Ecopoetics N2 - No abstract available. KW - Animal Studies KW - Cultural Animal Studies KW - Cultural Studies KW - Ecocriticism KW - Environmental Humanities KW - Human-Animal Studies KW - Literary Studies Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178074 UR - https://www.rombach-verlag.de/buecher/suchergebnis/rombach/buch/details/texts-animals-environments.html PB - Rombach Druck- und Verlagshaus CY - Freiburg i. Br. ER - TY - JOUR A1 - Beer, Katharina A1 - Joschinski, Jens A1 - Sastre, Alazne Arrazola A1 - Krauss, Jochen A1 - Helfrich-Förster, Charlotte T1 - A damping circadian clock drives weak oscillations in metabolism and locomotor activity of aphids (Acyrthosiphon pisum) JF - Scientific Reports N2 - Timing seasonal events, like reproduction or diapause, is crucial for the survival of many species. Global change causes phenologies worldwide to shift, which requires a mechanistic explanation of seasonal time measurement. Day length (photoperiod) is a reliable indicator of winter arrival, but it remains unclear how exactly species measure day length. A reference for time of day could be provided by a circadian clock, by an hourglass clock, or, as some newer models suggest, by a damped circadian clock. However, damping of clock outputs has so far been rarely observed. To study putative clock outputs of Acyrthosiphon pisum aphids, we raised individual nymphs on coloured artificial diet, and measured rhythms in metabolic activity in light-dark illumination cycles of 16:08 hours (LD) and constant conditions (DD). In addition, we kept individuals in a novel monitoring setup and measured locomotor activity. We found that A. pisum is day-active in LD, potentially with a bimodal distribution. In constant darkness rhythmicity of locomotor behaviour persisted in some individuals, but patterns were mostly complex with several predominant periods. Metabolic activity, on the other hand, damped quickly. A damped circadian clock, potentially driven by multiple oscillator populations, is the most likely explanation of our results. KW - circadian mechanisms KW - behavioural ecology KW - damped circadian clock KW - Acyrthosiphon pisum Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170020 VL - 7 IS - 14906 ER - TY - JOUR A1 - Reuss, Heiko A1 - Kiesel, Andrea A1 - Kunde, Wilfried A1 - Wühr, Peter T1 - A cue from the unconscious - masked symbols prompt spatial anticipation JF - Frontiers in Psychology N2 - Anticipating where an event will occur enables us to instantaneously respond to events that occur at the expected location. Here we investigated if such spatial anticipations can be triggered by symbolic information that participants cannot consciously see. In two experiments involving a Posner cueing task and a visual search task, a central cue informed participants about the likely location of the next target stimulus. In half of the trials, this cue was rendered invisible by pattern masking. In both experiments, visible cues led to cueing effects, that is, faster responses after valid compared to invalid cues. Importantly, even masked cues caused cueing effects, though to a lesser extent. Additionally, we analyzed effects on attention that persist from one trial to the subsequent trial. We found that spatial anticipations are able to interfere with newly formed spatial anticipations and influence orienting of attention in the subsequent trial. When the preceding cue was visible, the corresponding spatial anticipation persisted to an extent that prevented a noticeable effect of masked cues. The effects of visible cues were likewise modulated by previous spatial anticipations, but were strong enough to also exert an impact on attention themselves. Altogether, the results suggest that spatial anticipations can be formed on the basis of unconscious stimuli, but that interfering influences like still active spatial anticipations can suppress this effect. KW - masked priming KW - unconscious processing KW - anticipation KW - endogenous shifts of attention KW - spatial cueing Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-123971 VL - 3 ER - TY - JOUR A1 - Reymus, M. A1 - Stawarczyk, B. A1 - Winkler, A. A1 - Ludwig, J. A1 - Kess, S. A1 - Krastl, G. A1 - Krug, R. T1 - A critical evaluation of the material properties and clinical suitability of in‐house printed and commercial tooth replicas for endodontic training JF - International Endodontic Journal N2 - Aim To assess the suitability of several 3D‐printed resins for the manufacturing of tooth replicas for endodontic training in comparison with commercially available replicas by analysing the properties of the materials and comparing them with real teeth during endodontic training. Methodology Tooth replicas were 3D‐printed using four resins (NextDent Model, NextDent C&B, V‐Print ee and Vero White Plus) and compared with two commercially available products (VDW and Smile Factory) as well as extracted human teeth. Martens hardness, indentation modulus and radiopacity were investigated on these tooth replicas. Experienced dentists evaluated the suitability of the replicas for endodontic training by comparing them with real teeth in terms of appearance, anatomy, radiopacity, similarity to dentine during access opening, canal gauging and canal instrumentation. Data were analysed using the Kolmogorov–Smirnov and Mann–Whitney U‐test. Results The greatest hardness values were recorded for human dentine (P < 0.001), followed by V‐Print ee and the commercial tooth replica of Smile Factory. The greatest radiopacity was associated with VOC and dentine (P < 0.001) in comparison with the other materials tested. The appearance of the in‐house printed tooth replicas was subjectively evaluated by the dentists as being more realistic than the commercially available products. No differences between the replicas was detected during mechanical instrumentation of root canals. Conclusion None of the tooth replicas were able to simulate human dentine from the perspectives evaluated. V‐Print ee had radiopacity comparable with dentine, but its hardness was not comparable with dentine. KW - 3D Printing KW - dental education KW - replica KW - undergraduate training Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218085 VL - 53 IS - 10 SP - 1446 EP - 1454 ER - TY - JOUR A1 - Staiger, Christine A1 - Cadot, Sidney A1 - Kooter, Raul A1 - Dittrich, Marcus A1 - Müller, Tobias A1 - Klau, Gunnar W. A1 - Wessels, Lodewyk F. A. T1 - A Critical Evaluation of Network and Pathway-Based Classifiers for Outcome Prediction in Breast Cancer JF - PLoS One N2 - Recently, several classifiers that combine primary tumor data, like gene expression data, and secondary data sources, such as protein-protein interaction networks, have been proposed for predicting outcome in breast cancer. In these approaches, new composite features are typically constructed by aggregating the expression levels of several genes. The secondary data sources are employed to guide this aggregation. Although many studies claim that these approaches improve classification performance over single genes classifiers, the gain in performance is difficult to assess. This stems mainly from the fact that different breast cancer data sets and validation procedures are employed to assess the performance. Here we address these issues by employing a large cohort of six breast cancer data sets as benchmark set and by performing an unbiased evaluation of the classification accuracies of the different approaches. Contrary to previous claims, we find that composite feature classifiers do not outperform simple single genes classifiers. We investigate the effect of (1) the number of selected features; (2) the specific gene set from which features are selected; (3) the size of the training set and (4) the heterogeneity of the data set on the performance of composite feature and single genes classifiers. Strikingly, we find that randomization of secondary data sources, which destroys all biological information in these sources, does not result in a deterioration in performance of composite feature classifiers. Finally, we show that when a proper correction for gene set size is performed, the stability of single genes sets is similar to the stability of composite feature sets. Based on these results there is currently no reason to prefer prognostic classifiers based on composite features over single genes classifiers for predicting outcome in breast cancer. KW - modules KW - protein-interaction networks KW - expression signature KW - classification KW - set KW - metastasis KW - stability KW - survival KW - database KW - markers Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131323 VL - 7 IS - 4 ER - TY - JOUR A1 - Karak, Suvendu A1 - Stepanenko, Vladimir A1 - Addicoat, Matthew A. A1 - Keßler, Philipp A1 - Moser, Simon A1 - Beuerle, Florian A1 - Würthner, Frank T1 - A Covalent Organic Framework for Cooperative Water Oxidation JF - Journal of the American Chemical Society N2 - The future of water-derived hydrogen as the “sustainable energy source” straightaway bets on the success of the sluggish oxygen-generating half-reaction. The endeavor to emulate the natural photosystem II for efficient water oxidation has been extended across the spectrum of organic and inorganic combinations. However, the achievement has so far been restricted to homogeneous catalysts rather than their pristine heterogeneous forms. The poor structural understanding and control over the mechanistic pathway often impede the overall development. Herein, we have synthesized a highly crystalline covalent organic framework (COF) for chemical and photochemical water oxidation. The interpenetrated structure assures the catalyst stability, as the catalyst’s performance remains unaltered after several cycles. This COF exhibits the highest ever accomplished catalytic activity for such an organometallic crystalline solid-state material where the rate of oxygen evolution is as high as ∼26,000 μmol L\(^{–1}\) s\(^{–1}\) (second-order rate constant k ≈ 1650 μmol L s\(^{–1}\) g\(^{–2}\)). The catalyst also proves its exceptional activity (k ≈ 1600 μmol L s\(^{–1}\) g\(^{–2}\)) during light-driven water oxidation under very dilute conditions. The cooperative interaction between metal centers in the crystalline network offers 20–30-fold superior activity during chemical as well as photocatalytic water oxidation as compared to its amorphous polymeric counterpart. KW - water oxidation KW - sustainable energy source KW - covalent organic framework KW - catalyst KW - crystalline KW - catalysis KW - nanoparticles Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-287591 UR - https://pubs.acs.org/doi/10.1021/jacs.2c07282 SN - 0002-7863 VL - 144 IS - 38 ER - TY - THES A1 - Lewandowska, Natalia Ewelina T1 - A Correlation Study of Radio Giant Pulses and Very High Energy Photons from the Crab Pulsar T1 - Eine Korrelationsstudie zwischen Riesenpulsen im Radiobereich und Photonen im Gammabereich vom Pulsar im Krebsnebel N2 - Pulsars (in short for Pulsating Stars) are magnetized, fast rotating neutron stars. The basic picture of a pulsar describes it as a neutron star which has a rotation axis that is not aligned with its magnetic field axis. The emission is assumed to be generated near the magnetic poles of the neutron star and emitted along the open magnetic field lines. Consequently, the corresponding beam of photons is emitted along the magnetic field line axis. The non-alignment of both, the rotation and the magnetic field axis, results in the effect that the emission of the pulsar is only seen if its beam points towards the observer. The emission from a pulsar is therefore perceived as being pulsed although its generation is not. This rather simple geometrical model is commonly referred to as Lighthouse Model and has been widely accepted. However, it does not deliver an explanation of the precise mechanisms behind the emission from pulsars (see below for more details). Nowadays more than 2000 pulsars are known. They are observed at various wavelengths. Multiwavelength studies have shown that some pulsars are visible only at certain wavelengths while the emission from others can be observed throughout large parts of the electromagnetic spectrum. An example of the latter case is the Crab pulsar which is also the main object of interest in this thesis. Originating from a supernova explosion observed in 1054 A.D. and discovered in 1968, the Crab pulsar has been the central subject of numerous studies. Its pulsed emission is visible throughout the whole electromagnetic spectrum which makes it a key figure in understanding the possible mechanisms of multiwavelength emission from pulsars. The Crab pulsar is also well known for its radio emission strongly varying on long as well as on short time scales. While long time scale behaviour from a pulsar is usually examined through the use of its average profile (a profile resulting from averaging of a large number of individual pulses resulting from single rotations), short time scale behaviour is examined via its single pulses. The short time scale anomalous behaviour of its radio emission is commonly referred to as Giant Pulses and represents the central topic of this thesis. While current theoretical approaches place the origin of the radio emission from a pulsar like the Crab near its magnetic poles (Polar Cap Model) as already indicated by the Lighthouse model, its emission at higher frequencies, especially its gamma-ray emission, is assumed to originate further away in the geometrical region surrounding a pulsar which is commonly referred to as a pulsar magnetosphere (Outer Gap Model). Consequently, the respective emission regions are usually assumed not to be connected. However, past observational results from the Crab pulsar represent a contradiction to this assumption. Radio giant pulses from the Crab pulsar have been observed to emit large amounts of energy on very short time scales implying small emission regions on the surface of the pulsar. Such energetic events might also leave a trace in the gamma-ray emission of the Crab pulsar. The aim of this thesis is to search for this connection in the form of a correlation study between radio giant pulses and gamma-photons from the Crab pulsar. To make such a study possible, a multiwavelength observational campaign was organized for which radio observations were independently applied for, coordinated and carried out with the Effelsberg radio telescope and the Westerbork Synthesis Radio Telescope and gamma-ray observations with the Major Atmospheric Imaging Cherenkov telescopes. The corresponding radio and gamma-ray data sets were reduced and the correlation analysis thereafter consisted of three different approaches: 1) The search for a clustering in the differences of the times of arrival of radio giant pulses and gamma-photons; 2) The search for a linear correlation between radio giant pulses and gamma-photons using the Pearson correlation approach; 3) A search for an increase of the gamma-ray flux around occurring radio giant pulses. In the last part of the correlation study an increase of the number of gamma-photons centered on a radio giant pulse by about 17% (in contrast with the number of gamma-photons when no radio giant pulse occurs in the same time window) was discovered. This finding suggests that a new theoretical approach for the emission of young pulsars like the Crab pulsar, is necessary. N2 - Pulsare (Kurzform von Pulsating Stars) sind stark magnetisierte, rotierende Neutronensterne. Nach dem Standardmodell ist ein Pulsar ein Neutronenstern mit einer Rotationsachse, die nicht entlang der Achse seines Magnetfelds ausgerichtet ist. Es wird angenommen, dass die Pulsarstrahlung in der Nähe der Pole des Neutronensterns an offenen Magnetfeldlinien entsteht. Der dadurch entstehende Photonenstrahl wird entlang der Magnetfeldachse emittiert. Die unterschiedlichen Ausrichtungen der Rotations- und Magnetfeldachse führen dazu, dass die Strahlung des Pulsars von einem Beobachter nur wahrgenommen wird, wenn der Photonenstrahl die Sichtlinie des Beobachters überstreicht. Durch diesen Effekt wird beim Beobachter der Anschein erweckt die Pulsarstrahlung sei gepulst, obwohl sie kontinuerlich produziert wird. Dieses vereinfachte geometrische Model, in der Literatur oftmals als Leuchtturm Modell bezeichnet, ist heutzutage weitestgehend akzeptiert. Es liefert dennoch keine Erklärung für die genaue Entstehung der Pulsarstrahlung (siehe weiter unten). Heutzutage sind mehr als 2000 Pulsare bekannt und werden mittlerweile nicht nur bei Radiowellenlängen untersucht. Multiwellenlängenstudien haben zu der Entdeckung geführt, dass einige Pulsar nur in bestimmten Wellenlängenbereichen sichtbar sind, während die Strahlung von anderen Pulsaren in weiten Teilen des elektromagnetischen Spektrums nachgewiesen werden kann. Ein Beispiel für letzteren Fall ist der Crab Pulsar, das Objekt das die vorliegende Arbeit hauptsächlich betrachtet. Entstanden in einer Supernova, die im Jahre 1054 n.Chr. beobachtet wurde, wurde er 1968 als stellarer Überrest dieser Explosion entdeckt und seitdem im Rahmen zahlreicher Studien untersucht. Seine gepulste Strahlung kann im gesamten elektromagnetischen Spektrum nachgewiesen werden. Diese Eigenschaft macht ihn zu einem Schlüsselobjekt für die Erforschung möglicher Emissionsmechanismen der Strahlung von Pulsaren. Eine weitere Besonderheit des Crab Pulsars liegt auch in dem anomalen Verhalten seiner Radiostrahlung auf kurzen Zeitskalen. Während das Langzeitverhalten eines Pulsars mittels seines mittleren Pulsprofiles (eines Profils resultierend aus der Mittelung vieler Einzelpulse aus einzelnen Rotationen) untersucht wird, wird das Kurzzeitverhalten mittels einzelner Pulse untersucht. Als anomales Verhalten der Radiostrahlung des Crab Pulsars auf diesen kurzen Zeitskalen sind die sogenannten Riesenpulse (Giant Pulses) von Interesse. Einzelpulse dieser Art sind der zentrale zu untersuchende Aspekt der vorliegenden Arbeit. Gängige theoretische Modelle gehen davon aus, dass die Radiostrahlung eines Pulsars in der Nähe der Pole entsteht (Polar Cap Model), wie zuvor vom Leuchtturm Model impliziert wurde, während die hochfrequente Strahlung, wie z.B. die gamma-Strahlung, weiter außen in der Magnetosphäre, die den Pulsar umgibt, entsteht (Outer Gap Model). Ausgehend von diesen beiden theoretischen Ansätzen, wird angenommen, dass die entsprechenden Entstehungsregionen nicht miteinander verbunden sind. Die bisherigen Beobachtungen des Crab Pulsars widersprechen jedoch dieser Annahme. Untersuchungen der Riesenpulse des Crab Pulsars im Radiobereich haben ergeben, dass diese Einzelpulse große Energiemengen binnen sehr kurzen Zeitskalen freisetzen. Dieses Phänomen deutet auf sehr kleine Emissionsregionen auf der Oberfläche des Pulsars hin. Eine Freisetzung dieser Energiemengen könnte auch Spuren im Bereich der hochenergetischen gamma-Strahlung hinterlassen. Das Ziel der vorliegenden Arbeit ist daher eine Untersuchung einer möglichen Verbindung zwischen den Radiopulsen des Crab Pulsars im Radiobereich und seiner gamma-Strahlung in der Form einer Korrelationsstudie. Um eine solche Studie zu ermöglichen, wurde eine Multiwellenlängen Beobachtungskampagne organisiert. Im Rahmen dieser Kampagne wurden selbstständig Radiobeobachtungen am Effelsberger Radioteleskop und am Westerbork Synthesis Radio Telescope und gamma-Beobachtungen an den Major Atmospheric Imaging Cherenkov Teleskopen erfolgreich beantragt, koordiniert und (teilweise selbstständig vor Ort) ausgeführt. Die daraus entstehenden Datensätze wurden entsprechend bearbeitet und in der resultierenden Korrelationsanalyse wurden die folgenden Aspekte untersucht: 1) Eine Anhäufung in den Ankunftszeiten von Riesenpulsen und gamma-Photonen; 2) Eine Suche nach einer linearen Korrelation zwischen Riesenpulsen und gamma-Photonen mittels der Pearson Korrelation; 3) Eine Suche nach einer Erhöhung des Flusses von gamma-Photonen in der zeitlichen Umgebung eines Riesenpulses im Radiobereich. Im letzten Teil der Analyse konnte eine Erhöhung der Anzahl von gamma-Photonen, die zeitlich auf einem Riesenpuls zentriert sind, von ungefähr 17% (im Vergleich zu der entsprechenden Anzahl im gleichen Zeitfenster, wenn kein Riesenpuls vorhanden ist) nachgewiesen werden. Dieses Ergebnis gibt einen wichtigen Impuls für die Überarbeitung der bereits vorhandenen Emissionsmodelle von jungen Pulsaren wie dem Crab Pulsar. KW - Pulsar KW - Crab-Nebel KW - Gammaastronomie KW - Radioastronomie KW - crab pulsar KW - giant pulses KW - neutron star KW - correlation KW - radio astronomy KW - gamma astronomy KW - Radiofrequenzstrahlung KW - Gammastrahlenastronomie KW - Korrelation Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-123533 ER - TY - JOUR A1 - Jain, M. A1 - Vélez, J. I. A1 - Acosta, M. T. A1 - Palacio, L. G. A1 - Balog, J. A1 - Roessler, E. A1 - Pineda, D. A1 - Londoño, A. C. A1 - Palacio, J. D. A1 - Arbelaez, A. A1 - Lopera, F. A1 - Elia, J. A1 - Hakonarson, H. A1 - Seitz, C. A1 - Freitag, C. M. A1 - Palmason, H. A1 - Meyer, J. A1 - Romanos, M. A1 - Walitza, S. A1 - Hemminger, U. A1 - Warnke, A. A1 - Romanos, J. A1 - Renner, T. A1 - Jacob, C. A1 - Lesch, K.-P. A1 - Swanson, J. A1 - Castellanos, F. X. A1 - Bailey-Wilson, J. E. A1 - Arcos-Burgos, M. A1 - Muenke, M. T1 - A cooperative interaction between LPHN3 and 11q doubles the risk for ADHD JF - Molecular Psychiatry N2 - In previous studies of a genetic isolate, we identified significant linkage of attention deficit hyperactivity disorder (ADHD) to 4q, 5q, 8q, 11q and 17p. The existence of unique large size families linked to multiple regions, and the fact that these families came from an isolated population, we hypothesized that two-locus interaction contributions to ADHD were plausible. Several analytical models converged to show significant interaction between 4q and 11q (P<1 × 10−8) and 11q and 17p (P<1 × 10−6). As we have identified that common variants of the LPHN3 gene were responsible for the 4q linkage signal, we focused on 4q–11q interaction to determine that single-nucleotide polymorphisms (SNPs) harbored in the LPHN3 gene interact with SNPs spanning the 11q region that contains DRD2 and NCAM1 genes, to double the risk of developing ADHD. This interaction not only explains genetic effects much better than taking each of these loci effects by separated but also differences in brain metabolism as depicted by proton magnetic resonance spectroscopy data and pharmacogenetic response to stimulant medication. These findings not only add information about how high order genetic interactions might be implicated in conferring susceptibility to develop ADHD but also show that future studies of the effects of genetic interactions on ADHD clinical information will help to shape predictive models of individual outcome. KW - ADHD KW - genetic interaction KW - LPHN3 KW - NCAM1 KW - DRD2 Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125128 VL - 17 ER - TY - JOUR A1 - Hünig, Siegfried A1 - Wehner, Ingeborg T1 - A convenient synthesis of 2,2',6,6'-Tetramethyl-4,4'-bipyridine and its oxidation to 2,2',6,6'-Tetracarboxy-4,4'-bipyridine N2 - No abstract available Y1 - 1989 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-32005 ER - TY - THES A1 - Gründler, Klaus T1 - A Contribution to the Empirics of Economic Development - The Role of Technology, Inequality, and the State T1 - Eine empirische Untersuchung der wirtschaftlichen Entwicklung - Die Rolle von Technologien, Ungleichheit und dem Staat N2 - This dissertation contributes to the empirical analysis of economic development. The continuing poverty in many Sub-Saharan-African countries as well as the declining trend in growth in the advanced economies that was initiated around the turn of the millennium raises a number of new questions which have received little attention in recent empirical studies. Is culture a decisive factor for economic development? Do larger financial markets trigger positive stimuli with regard to incomes, or is the recent increase in their size in advanced economies detrimental to economic growth? What causes secular stagnation, i.e. the reduction in growth rates of the advanced economies observable over the past 20 years? What is the role of inequality in the growth process, and how do governmental attempts to equalize the income distribution affect economic development? And finally: Is the process of democratization accompanied by an increase in living standards? These are the central questions of this doctoral thesis. To facilitate the empirical analysis of the determinants of economic growth, this dissertation introduces a new method to compute classifications in the field of social sciences. The approach is based on mathematical algorithms of machine learning and pattern recognition. Whereas the construction of indices typically relies on arbitrary assumptions regarding the aggregation strategy of the underlying attributes, utilization of Support Vector Machines transfers the question of how to aggregate the individual components into a non-linear optimization problem. Following a brief overview of the theoretical models of economic growth provided in the first chapter, the second chapter illustrates the importance of culture in explaining the differences in incomes across the globe. In particular, if inhabitants have a lower average degree of risk-aversion, the implementation of new technology proceeds much faster compared with countries with a lower tendency towards risk. However, this effect depends on the legal and political framework of the countries, their average level of education, and their stage of development. The initial wealth of individuals is often not sufficient to cover the cost of investments in both education and new technologies. By providing loans, a developed financial sector may help to overcome this shortage. However, the investigations in the third chapter show that this mechanism is dependent on the development levels of the economies. In poor countries, growth of the financial sector leads to better education and higher investment levels. This effect diminishes along the development process, as intermediary activity is increasingly replaced by speculative transactions. Particularly in times of low technological innovation, an increasing financial sector has a negative impact on economic development. In fact, the world economy is currently in a phase of this kind. Since the turn of the millennium, growth rates in the advanced economies have experienced a multi-national decline, leading to an intense debate about "secular stagnation" initiated at the beginning of 2015. The fourth chapter deals with this phenomenon and shows that the growth potentials of new technologies have been gradually declining since the beginning of the 2000s. If incomes are unequally distributed, some individuals can invest less in education and technological innovations, which is why the fifth chapter identifies an overall negative effect of inequality on growth. This influence, however, depends on the development level of countries. While the negative effect is strongly pronounced in poor economies with a low degree of equality of opportunity, this influence disappears during the development process. Accordingly, redistributive polices of governments exert a growth-promoting effect in developing countries, while in advanced economies, the fostering of equal opportunities is much more decisive. The sixth chapter analyzes the growth effect of the political environment and shows that the ambiguity of earlier studies is mainly due to unsophisticated measurement of the degree of democratization. To solve this problem, the chapter introduces a new method based on mathematical algorithms of machine learning and pattern recognition. While the approach can be used for various classification problems in the field of social sciences, in this dissertation it is applied for the problem of democracy measurement. Based on different country examples, the chapter shows that the resulting SVMDI is superior to other indices in modeling the level of democracy. The subsequent empirical analysis emphasizes a significantly positive growth effect of democracy measured via SVMDI. N2 - Die Dissertation beschäftigt sich mit der statistischen und empirischen Analyse der Determinanten langfristiger Wachstumsprozesse. Die anhaltende Armut vieler Staaten in Subsahara-Afrika sowie die rückläufigen Wachstumsraten der reichen Volkswirtschaften seit Beginn des neuen Jahrtausends werfen eine Reihe neuer Fragen auf, die bislang wenig empirisch erforscht sind. Ist die Kultur eines Landes entscheidend für die Entwicklung der Wohlfahrt? Kann ein entwickelter Finanzsektor Wohlstandssteigerungen auslösen, oder ist der starke Zuwachs der Finanzmärkte, der in den Industrienationen beobachtet werden kann, schädlich für die Entwicklung? Warum wachsen reiche Volkswirtschaften heute so viel langsamer als noch vor 20 Jahren? Welchen Einfluss nimmt die zunehmende Einkommensungleichheit auf die wirtschaftliche Entwicklung und welchen Effekt haben staatliche Umverteilungsmaßnahmen? Und schließlich: Führen stärkere politische Rechte und mehr Demokratie zu einer Zunahme der Lebensstandards? Dies sind die zentralen Fragestellungen, denen sich die Kapitel dieser Doktorarbeit widmen. Um die Analyse der empirischen Ursachen der wirtschaftlichen Entwicklung zu erleichtern, leitet die Dissertation überdies ein neues Verfahren zur Lösung von Klassifikationsproblemen in den Sozialwissenschaften ab. Das Verfahren beruht auf mathematischen Algorithmen zur Mustererkennung und des maschinellen Lernens. Dies bietet neue Möglichkeiten für das Konstruieren von Indizes, die zumeist auf arbiträre Annahmen über die zugrundeliegende Aggregationsfunktion zurückgreifen. Das vorgestellte Verfahren löst dieses Problem, in dem die Aggregation durch Support Vector Machines in ein nicht-lineares Optimierungsproblem überführt wird. Nach einem kurzen Überblick über die theoretischen Erklärungsansätze der wirtschaftlichen Entwicklung im ersten Kapitel zeigt das zweite Kapitel, dass kulturelle Unterschieden einen Einfluss auf die ökonomische Entwicklung ausüben. Die Ergebnisse implizieren, dass Länder mit einer geringeren Aversion gegen Risiken höhere Wachstumsraten aufweisen, da in diesen Ländern die Implementierung neuer Technologien schneller voranschreitet. Der Effekt ist allerdings abhängig von den rechtlichen und politischen Rahmenbedingungen der Länder, vom durchschnittlichen Bildungsniveau sowie vom Entwicklungsstand. In vielen Fällen reichen die Vermögen der Individuen nicht aus, um Investitionen in Bildung, Kapital und neue Technologien zu stemmen. Durch die Bereitstellung von Krediten kann ein entwickelter Finanzsektor diesen Engpass überwinden. Die Untersuchungen des dritten Kapitels zeigen allerdings, dass dieser Mechanismus abhängig ist von den Entwicklungsniveaus der Volkswirtschaften. In armen Ländern führt ein Anstieg des Finanzsektors zu besserer Bildung und höheren Investitionen. Dieser Effekt nimmt jedoch über den Entwicklungsprozess ab, da die Intermediationstätigkeit zunehmend durch spekulative Geschäfte ersetzt wird. Insbesondere in Zeiten mit geringen technologischen Neuerungen wirkt ein wachsender Finanzsektor negativ auf die ökonomische Entwicklung. Aktuell befindet sich die Weltökonomie in einer solchen Phase, was verbunden mit einem multinationalen Rückgang der Wachstumsraten seit Anfang 2015 als "säkulare Stagnation" diskutiert wird. Das vierte Kapitel befasst sich intensiv mit diesem Phänomen und zeigt, dass die gegenwärtigen Wachstumspotenziale neuer Technologien seit Beginn der 2000er Jahre zunehmend auslaufen. Sind die Einkommen ungleich verteilt, so können einige Individuen weniger Investitionen in Bildung und technologische Neuerungen durchführen. Tatsächlich weist das fünfte Kapitel auf einen insgesamt negativen Effekt der Ungleichheit auf das Wachstum hin. Dieser Einfluss ist allerdings abhängig vom Entwicklungsstand der Länder. Während der negative Effekt in armen Volkswirtschaften mit einem geringen Maß an Chancengleichheit stark ausgeprägt ist, verschwindet dieser Einfluss mit zunehmendem Entwicklungsniveau. Entsprechend wirkt direkte staatliche Umverteilung vor allem in unterentwickelten Ländern wachstumsfördernd. In entwickelten Nationen ist hingegen die Schaffung von Chancengleichheit entscheidend. Das sechste Kapitel analysiert den Wachstumseffekt des politischen Umfelds und zeigt, dass die Ambivalenz früherer Studien auf die mangelhafte Abbildung des Demokratiegrades zurückzuführen ist. Zur Lösung dieses Problems wird ein neues Verfahren vorgeschlagen, das auf mathematischen Algorithmen des maschinellen Lernens basiert. Das Verfahren kann in verschiedenen Bereichen der Sozialwissenschaften eingesetzt werden und wird in der Arbeit zur Klassifikation des Demokratiegrades angewandt. Auf Basis verschiedener Länderbeispiele wird deutlich, dass der resultierende SVMDI anderen Indizes in der Modellierung des Demokratiegrades überlegen ist. Die anschließende empirische Analyse betont einen signifikant positiven Effekt des SVMDI auf das Wirtschaftswachstum. N2 - Why are some nations rich and others poor? What are the sources of long-run economic development and growth? How can living standards be increased? In this book, Klaus Gründler empirically analyses these central economic questions and puts a particular emphasis on the role of technology, inequality, and political institutions. To substantiate his empirical studies, he introduces a new method to compute composite measures and indices that is based on mathematical algorithms from the field of machine learning. KW - Wirtschaftsentwicklung KW - Wirtschaftsstruktur KW - Sozioökonomisches System KW - Inequality KW - Economic Growth KW - Machine Learning KW - Empirical Economics KW - Ungleichheit KW - Wirtschaftswachstum KW - Maschinelles Lernen KW - Makroökonomie KW - Empirische Wirtschaftsforschung Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-141520 SN - 978-3-95826-072-6 (Print) SN - 978-3-95826-073-3 (Online) N1 - Parallel erschienen als Druckausgabe in Würzburg University Press, 978-3-95826-072-6, 41,80 EUR. PB - Würzburg University Press CY - Würzburg ET - 1. Auflage ER - TY - JOUR A1 - Fakhri, Seyed Arvin A1 - Latifi, Hooman T1 - A consumer grade UAV-based framework to estimate structural attributes of coppice and high oak forest stands in semi-arid regions JF - Remote Sensing N2 - Semi-arid tree covers, in both high and coppice growth forms, play an essential role in protecting water and soil resources and provides multiple ecosystem services across fragile ecosystems. Thus, they require continuous inventories. Quantification of forest structure in these tree covers provides important measures for their management and biodiversity conservation. We present a framework, based on consumer-grade UAV photogrammetry, to separately estimate primary variables of tree height (H) and crown area (A) across diverse coppice and high stands dominated by Quercus brantii Lindl. along the latitudinal gradient of Zagros mountains of western Iran. Then, multivariate linear regressions were parametrized with H and A to estimate the diameter at breast height (DBH) of high trees because of its importance to accelerate the existing practical DBH inventories across Zagros Forests. The estimated variables were finally applied to a model tree aboveground biomass (AGB) for both vegetative growth forms by local allometric equations and Random Forest models. In each step, the estimated variables were evaluated against the field reference values, indicating practically high accuracies reaching root mean square error (RMSE) of 0.68 m and 4.74 cm for H and DBH, as well as relative RMSE < 10% for AGB estimates. The results generally suggest an effective framework for single tree-based attribute estimation over mountainous, semi-arid coppice, and high stands. KW - tree structure KW - biomass KW - DBH KW - Zagros Forests KW - Q. brantii Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248469 SN - 2072-4292 VL - 13 IS - 21 ER - TY - JOUR A1 - Hirsch, Martin A1 - Krauss, Manuel E. A1 - Opferkuch, Toby A1 - Porod, Werner A1 - Staub, Florian T1 - A constrained supersymmetric left-right model JF - JOURNAL OF HIGH ENERGY PHYSICS N2 - We present a supersymmetric left-right model which predicts gauge coupling unification close to the string scale and extra vector bosons at the TeV scale. The subtleties in constructing a model which is in agreement with the measured quark masses and mixing for such a low left-right breaking scale are discussed. It is shown that in the constrained version of this model radiative breaking of the gauge symmetries is possible and a SM-like Higgs is obtained. Additional CP-even scalars of a similar mass or even much lighter are possible. The expected mass hierarchies for the supersymmetric states differ clearly from those of the constrained MSSM. In particular, the lightest down-type squark, which is a mixture of the sbottom and extra vector-like states, is always lighter than the stop. We also comment on the model’s capability to explain current anomalies observed at the LHC. KW - supersymmetry KW - phenomenology KW - LHC Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-168016 VL - 03 IS - 009 ER - TY - JOUR A1 - Haack, J. A1 - Hauck, C. A1 - Klingenberg, C. A1 - Pirner, M. A1 - Warnecke, S. T1 - A Consistent BGK Model with Velocity-Dependent Collision Frequency for Gas Mixtures JF - Journal of Statistical Physics N2 - We derive a multi-species BGK model with velocity-dependent collision frequency for a non-reactive, multi-component gas mixture. The model is derived by minimizing a weighted entropy under the constraint that the number of particles of each species, total momentum, and total energy are conserved. We prove that this minimization problem admits a unique solution for very general collision frequencies. Moreover, we prove that the model satisfies an H-Theorem and characterize the form of equilibrium. KW - plasma physics KW - multi-fluid mixture KW - kinetic model KW - BGK approximation KW - velocity-dependent collision frequency KW - entropy minimization Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-269146 SN - 1572-9613 VL - 184 IS - 3 ER - TY - JOUR A1 - Libre, Camille A1 - Seissler, Tanja A1 - Guerrero, Santiago A1 - Batisse, Julien A1 - Verriez, Cédric A1 - Stupfler, Benjamin A1 - Gilmer, Orian A1 - Cabrera-Rodriguez, Romina A1 - Weber, Melanie M. A1 - Valenzuela-Fernandez, Agustin A1 - Cimarelli, Andrea A1 - Etienne, Lucie A1 - Marquet, Roland A1 - Paillart, Jean-Christophe T1 - A conserved uORF regulates APOBEC3G translation and is targeted by HIV-1 Vif protein to repress the antiviral factor JF - Biomedicines N2 - The HIV-1 Vif protein is essential for viral fitness and pathogenicity. Vif decreases expression of cellular restriction factors APOBEC3G (A3G), A3F, A3D and A3H, which inhibit HIV-1 replication by inducing hypermutation during reverse transcription. Vif counteracts A3G at several levels (transcription, translation, and protein degradation) that altogether reduce the levels of A3G in cells and prevent its incorporation into viral particles. How Vif affects A3G translation remains unclear. Here, we uncovered the importance of a short conserved uORF (upstream ORF) located within two critical stem-loop structures of the 5′ untranslated region (5′-UTR) of A3G mRNA for this process. A3G translation occurs through a combination of leaky scanning and translation re-initiation and the presence of an intact uORF decreases the extent of global A3G translation under normal conditions. Interestingly, the uORF is also absolutely required for Vif-mediated translation inhibition and redirection of A3G mRNA into stress granules. Overall, we discovered that A3G translation is regulated by a small uORF conserved in the human population and that Vif uses this specific feature to repress its translation. KW - HIV-1 KW - APOBEC3G KW - Vif KW - mRNA KW - translation KW - uORF Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-252147 SN - 2227-9059 VL - 10 IS - 1 ER - TY - JOUR A1 - Fröhlich, Kathrin S. A1 - Papenfort, Kai A1 - Berger, Allison A. A1 - Vogel, Jörg T1 - A conserved RpoS-dependent small RNA controls the synthesis of major porin OmpD JF - Nucleic Acids Research N2 - A remarkable feature of many small non-coding RNAs (sRNAs) of Escherichia coli and Salmonella is their accumulation in the stationary phase of bacterial growth. Several stress response regulators and sigma factors have been reported to direct the transcription of stationary phase-specific sRNAs, but a widely conserved sRNA gene that is controlled by the major stationary phase and stress sigma factor, Sigma(S) (RpoS), has remained elusive. We have studied in Salmonella the conserved SdsR sRNA, previously known as RyeB, one of the most abundant stationary phase-specific sRNAs in E. coli. Alignments of the sdsR promoter region and genetic analysis strongly suggest that this sRNA gene is selectively transcribed by Sigma(S). We show that SdsR down-regulates the synthesis of the major Salmonella porin OmpD by Hfq-dependent base pairing; SdsR thus represents the fourth sRNA to regulate this major outer membrane porin. Similar to the InvR, MicC and RybB sRNAs, SdsR recognizes the ompD mRNA in the coding sequence, suggesting that this mRNA may be primarily targeted downstream of the start codon. The SdsR-binding site in ompD was localized by 3'-RACE, an experimental approach that promises to be of use in predicting other sRNA-target interactions in bacteria. KW - shock sigma factor KW - general stress response KW - down regulation KW - stationary phase KW - salmonella enterica KW - messenger RNA KW - escherichia coli KW - enterica serovar typhimurium KW - outer-membrane proteins KW - small noncoding RNAs Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-134230 VL - 40 IS - 8 ER - TY - JOUR A1 - Sander, Bodo A1 - Xu, Wenshan A1 - Eilers, Martin A1 - Popov, Nikita A1 - Lorenz, Sonja T1 - A conformational switch regulates the ubiquitin ligase HUWE1 JF - eLife N2 - The human ubiquitin ligase HUWE1 has key roles in tumorigenesis, yet it is unkown how its activity is regulated. We present the crystal structure of a C-terminal part of HUWE1, including the catalytic domain, and reveal an asymmetric auto-inhibited dimer. We show that HUWE1 dimerizes in solution and self-associates in cells, and that both occurs through the crystallographic dimer interface. We demonstrate that HUWE1 is inhibited in cells and that it can be activated by disruption of the dimer interface. We identify a conserved segment in HUWE1 that counteracts dimer formation by associating with the dimerization region intramolecularly. Our studies reveal, intriguingly, that the tumor suppressor p14ARF binds to this segment and may thus shift the conformational equilibrium of HUWE1 toward the inactive state. We propose a model, in which the activity of HUWE1 underlies conformational control in response to physiological cues—a mechanism that may be exploited for cancer therapy. KW - Medicine KW - Structural Biology KW - Molecular Biophysics KW - HUWE1 KW - HECT Ligase KW - Ubiquitin KW - P14ARF KW - X-Ray Chrystallography KW - Enzyme Regulation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171862 VL - 6 ER - TY - THES A1 - Rüth, Michael T1 - A Comprehensive Study of Dilute Magnetic Semiconductor Resonant Tunneling Diodes T1 - Umfassende Untersuchung von resonanten Tunneldioden aus verdünnt-magnetischen Halbleitern N2 - We investigate transport measurements on all II-VI semiconductor resonant tunneling diodes (RTDs). Being very versatile, the dilute magnetic semiconductor (DMS) system (Zn,Be,Mn,Cd)Se is a perfect testbed for various spintronic device designs, as it allows for separate control of electrical and magnetic properties. In contrast to the ferromagnetic semiconductor (Ga,Mn)As, doping ZnSe with Mn impurities does not alter the electrical properties of the semiconductor, as the magnetic dopant is isoelectric in the ZnSe host. N2 - Diese Doktorarbeit befasst sich mit Transportmessungen an resonanten Tunneldioden (engl. resonant tunneling diode, RTD), welche vollst� andig aus II-VI Halbleitermaterial bestehen. Das verd� unnt magnetische (engl. dilute magnetic semiconductor, DMS) Halbleitermaterialsystem (Zn,Be,Mn,Cd)Se ist sehr vielseitig und eignet sich hervorragend als Testsystem f� ur diverse Spintronik Bauelemente, denn magnetische und elektrische Eigenschaften lassen sich getrennt voneinander einstellen. Im Gegensatz zum ferromagnetischen Halbleiter (Ga,Mn)As ver� andert das Dotieren von ZnSe mit Mn nicht die elektrischen Eigenschaften des Halbleiters. KW - Semimagnetischer Halbleiter KW - Resonanz-Tunneleffekt KW - Halbleiter KW - Resonante Tunneldioden KW - Spintronik KW - dilute magnetic semiconductors KW - spintronics KW - resonant tunneling diodes Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-71472 ER - TY - JOUR A1 - Peters, Simon A1 - Fohmann, Ingo A1 - Rudel, Thomas A1 - Schubert-Unkmeir, Alexandra T1 - A Comprehensive Review on the Interplay between Neisseria spp. and Host Sphingolipid Metabolites JF - Cells N2 - Sphingolipids represent a class of structural related lipids involved in membrane biology and various cellular processes including cell growth, apoptosis, inflammation and migration. Over the past decade, sphingolipids have become the focus of intensive studies regarding their involvement in infectious diseases. Pathogens can manipulate the sphingolipid metabolism resulting in cell membrane reorganization and receptor recruitment to facilitate their entry. They may recruit specific host sphingolipid metabolites to establish a favorable niche for intracellular survival and proliferation. In contrast, some sphingolipid metabolites can also act as a first line defense against bacteria based on their antimicrobial activity. In this review, we will focus on the strategies employed by pathogenic Neisseria spp. to modulate the sphingolipid metabolism and hijack the sphingolipid balance in the host to promote cellular colonization, invasion and intracellular survival. Novel techniques and innovative approaches will be highlighted that allow imaging of sphingolipid derivatives in the host cell as well as in the pathogen. KW - sphingolipids KW - host–pathogen interaction KW - Neisseria meningitidis KW - Neisseria gonorrhoeae Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250203 SN - 2073-4409 VL - 10 IS - 11 ER - TY - THES A1 - Ganz, Verena T1 - A comprehensive approach for currency crises theories stressing the role of the anchor country T1 - Ein umfassender Ansatz zur Integration von Währungskrisen-Theorien unter besonderer Berücksichtigung der Bedeutung des Ankerlandes N2 - The approach is based on the finding that new generations of currency crises theories always had developed ex post after popular currency crises. Discussing the main theories of currency crises shows their disparity: The First Generation of currency crises models argues based on the assumption of a chronic budget deficit that is being monetized by the domestic central bank. The result is a trade-off between an expansionary monetary policy that is focused on the internal economic balance and a fixed exchange rate which is depending on the rules of interest parity and purchasing power parity. This imbalance inevitably results in a currency crisis. Altogether, this theory argues with a disrupted external balance on the foreign exchange market. Second Generation currency crises models on the other side focus on the internal macroeconomic balance. The stability of a fixed exchange rate is depending on the economic benefit of the exchange rate system in relation to the social costs of maintaining it. As soon as social costs are increasing and showing up in deteriorating fundamentals, this leads to a speculative attack on the fixed exchange rate system. The term Third Generation of currency crises finally summarizes a variety of currency crises theories. These are also arguing psychologically to explain phenomena as contagion and spill-over effects to rationalize crises detached from the fundamental situation. Apart from the apparent inconsistency of the main theories of currency crises, a further observation is that these explanations focus on the crisis country only while international monetary transmission effects are left out of consideration. These however are a central parameter for the stability of fixed exchange rate systems, in exchange rate theory as well as in empirical observations. Altogether, these findings provide the motivation for developing a theoretical approach which integrates the main elements of the different generations of currency crises theories and which integrates international monetary transmission. Therefore a macroeconomic approach is chosen applying the concept of the Monetary Conditions Index (MCI), a linear combination of the real interest rate and the real exchange rate. This index firstly is extended for international monetary influences and called MCIfix. MCIfix illustrates the monetary conditions required for the stability of a fixed exchange rate system. The central assumption of this concept is that the uncovered interest parity is maintained. The main conclusion is that the MCIfix only depends on exogenous parameters. In a second step, the analysis integrates the monetary policy requirements for achieving an internal macroeconomic stability. By minimizing a loss function of social welfare, a MCI is derived which pictures the economically optimal monetary policy MCIopt. Instability in a fixed exchange rate system occurs as soon as the monetary conditions for an internal and external balance are deviating. For discussing macroeconomic imbalances, the central parameters determining the MCIfix (and therefore the relation of MCIfix to MCIopt) are discussed: the real interest rate of the anchor country, the real effective exchange rate and a risk premium. Applying this theory framework, four constellations are discussed where MCIfix and MCIopt fall apart in order to show the central bank’s possibilities for reacting and the consequences of that behaviour. The discussion shows that the integrative approach manages to incorporate the central elements of traditional currency crises theories and that it includes international monetary transmission instead of reducing the discussion on an inconsistent domestic monetary policy. The theory framework for fixed exchange rates is finally applied in four case studies: the currency crises in Argentina, the crisis in the Czech Republic, the Asian currency crisis and the crisis of the European Monetary System. The case studies show that the developed monetary framework achieves integration of different generations of crises theories and that the monetary policy of the anchor country plays a decisive role in destabilising fixed exchange rate systems. N2 - Die Arbeit baut auf dem Befund auf, dass zur Erklärung von Währungskrisen stets im Nachgang bedeutender Krisen eine neue Generation wissenschaftlicher Theorien entwickelt wurde. Eine Diskussion der bedeutendsten Theorien verdeutlicht, dass diese in ihrer Argumentation untereinander und in sich inkonsistent sind: Modelle Erster Generation bauen auf der Annahme chronischer Budgetdefizite auf, die die heimische Notenbank monetarisiert. Dieser Zielkonflikt zwischen einer expansiven, binnenwirtschaftlich ausgerichteten Geldpolitik und dem den Gesetzen der Zins- und Kaufkraftparität unterliegenden Wechselkursziel mündet unvermeidlich in einer Währungskrise. Die Theorie bezieht sich demnach klar auf das externe Gleichgewicht am Devisenmarkt. Währungskrisenmodelle der Zweiten Generation stellen dagegen das interne, binnenwirtschaftliche Gleichgewicht in den Mittelpunkt. Der Erfolg eines Wechselkurszieles hängt hiernach vom Nutzen des Festkurssystems in Relation zu den Kosten seiner Verteidigung ab. Steigen die sozialen Kosten in Form konjunktureller Belastungen, führt dies ab einem bestimmten Level über antizipierende Markterwartungen zu einer spekulativen Attacke auf den Festkurs. Unter dem Obergriff der Dritten Generation von Krisenmodellen schließlich werden verschiedene Modelle zusammengefasst, die psychologische Erklärungsansätze miteinbeziehen, um Phänomene wie Ansteckungseffekte zu erklären. Dadurch können Krisenentwicklungen losgelöst von der jeweiligen Fundamentaldatenlage rationalisiert werden. Neben der offensichtlichen Inkonsistenz der zentralen Argumente der jeweiligen Theorien ist eine weitere Beobachtung, dass die Erklärungen jeweils im betroffenen Land ansetzen, während eine grenzüberschreitende monetäre Transmission außer Acht gelassen wird. Diese ist jedoch sowohl in der Empirie als auch in der Theorie zu Wechselkurssystemen ein zentraler Einflussfaktor für die Stabilität von Festkurssystemen. Aus diesen Befunden leitet sich die Motivation für die vorliegende Arbeit ab, ein die verschiedenen Krisengenerationen integrierendes theoretisches Rahmenwerk zu entwickeln, in dem grenzüberschreitende monetäre Transmissionseffekte in die Diskussion mit einbezogen werden. Zu diesem Zweck wird ein makroökonomischer Ansatz gewählt, der das Konzept des Monetary Conditions Index (MCI) anwendet, einer Linearkombination aus Realzins und realem Wechselkurs. Dieser Index wird zum einen um internationale monetäre Einflüsse erweitert zu einem MCIfix, der die monetären Anforderungen an ein funktionierendes Festkurssystem wiederspiegelt. Zentrale Annahme hierfür ist die Einhaltung der ungedeckten Zinsparität. Die wesentliche Erkenntnis ist, dass alle Determinanten des MCIfix für die Notenbank exogene Parameter sind. In einem zweiten Schritt bezieht die Arbeit die binnenwirtschaftlichen Anforderungen einer Volkswirtschaft an die Geldpolitik in die Analyse ein. Dazu wird durch Minimierung einer Verlustfunktion an gesellschaftlicher Wohlfahrt ein MCI abgeleitet, der die binnenwirtschaftlich optimale Geldpolitik abbildet (MCIopt). Instabilität des Festkurssystems droht, sobald die geldpolitischen Bedingungen für das binnenwirtschaftliche und außenwirtschaftliche Gleichgewicht auseinanderfallen. Zur Diskussion makroökonomischer Ungleichgewichte werden die entscheidenden Parameter, die den MCIfix und damit die Relation von MCIfix und MCIopt bestimmen, diskutiert: der Realzins des Ankerlandes, der reale effektive Wechselkurs und eine Risikoprämie. Mit diesem Theorie-Instrumentarium stellt die Arbeit dann vier Konstellationen dar, in denen MCIfix und MCIopt auseinanderfallen, und diskutiert mögliche Verhaltensweisen der Notenbank und deren Folgen. Der MCI, für den sich die Notenbank tatsächlich entscheidet, wird als MCIact bezeichnet. Jeder der vier Fälle endet in einer Währungskrise. Es zeigt sich in der Diskussion, dass der hier verwendete Ansatz die zentralen Elemente traditioneller Krisentheorien integriert und die Diskussion monetärer Einflüsse von außen zulässt, anstatt ausschließlich von einem ursächlichen Verschulden der heimischen Notenbank auszugehen. Das theoretische Modell wird schließlich in vier Fallstudien angewandt: Der Argentinienkrise, dem Zusammenbruch des tschechischen Währungsregimes, der Asienkrise und der Krise des Europäischen Währungssystems. Die Fallstudien zeigen, dass sich mit dem entwickelten Modellrahmen Krisen verschiedener Generationen abbilden lassen und die Geldpolitik des Ankerlandes eine zentrale Rolle bei einer Destabilisierung eines Festkurssystems spielt. KW - Devisenmarkt KW - Wechselkurspolitik KW - Währungskrise KW - Fester Wechselkurs KW - Monetary Conditions Index KW - Ankerland KW - internes Gleichgewicht KW - externes Gleichgewicht KW - Monetary Conditions Index KW - anchor country KW - internal balance KW - external balance Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-26853 ER - TY - JOUR A1 - Pauls, Dennis A1 - Blechschmidt, Christine A1 - Frantzmann, Felix A1 - el Jundi, Basil A1 - Selcho, Mareike T1 - A comprehensive anatomical map of the peripheral octopaminergic/tyraminergic system of Drosophila melanogaster JF - Scientific Reports N2 - The modulation of an animal’s behavior through external sensory stimuli, previous experience and its internal state is crucial to survive in a constantly changing environment. In most insects, octopamine (OA) and its precursor tyramine (TA) modulate a variety of physiological processes and behaviors by shifting the organism from a relaxed or dormant condition to a responsive, excited and alerted state. Even though OA/TA neurons of the central brain are described on single cell level in Drosophila melanogaster, the periphery was largely omitted from anatomical studies. Given that OA/TA is involved in behaviors like feeding, flying and locomotion, which highly depend on a variety of peripheral organs, it is necessary to study the peripheral connections of these neurons to get a complete picture of the OA/TA circuitry. We here describe the anatomy of this aminergic system in relation to peripheral tissues of the entire fly. OA/TA neurons arborize onto skeletal muscles all over the body and innervate reproductive organs, the heart, the corpora allata, and sensory organs in the antennae, legs, wings and halteres underlining their relevance in modulating complex behaviors. KW - neural circuits KW - peripheral nervous system KW - Drosophila melanogaster Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-177412 VL - 8 IS - 15314 ER - TY - JOUR A1 - Hagemann, Carsten A1 - Anacker, Jelena A1 - Ernestus, Ralf-Ingo A1 - Vince, Giles H. T1 - A complete compilation of matrix metalloproteinase expression in human malignant gliomas JF - World Journal of Clinical Oncology N2 - Glioblastomas are characterized by an aggressive local growth pattern, a marked degree of invasiveness and poor prognosis. Tumor invasiveness is facilitated by the increased activity of proteolytic enzymes which are involved in destruction of the extracellular matrix of the surrounding healthy brain tissue. Elevated levels of matrix metalloproteinases (MMPs) were found in glioblastoma (GBM) cell-lines, as well as in GBM biopsies as compared with low-grade astrocytoma (LGA) and normal brain samples, indicating a role in malignant progression. A careful review of the available literature revealed that both the expression and role of several of the 23 human MMP proteins is controversely discussed and for some there are no data available at all. We therefore screened a panel of 15 LGA and 15 GBM biopsy samples for those MMPs for which there is either no, very limited or even contradictory data available. Hence, this is the first complete compilation of the expression pattern of all 23 human MMPs in astrocytic tumors. This study will support a better understanding of the specific expression patterns and interaction of proteolytic enzymes in malignant human glioma and may provide additional starting points for targeted patient therapy. KW - glioblastoma cell-lines KW - matrix metalloproteinase KW - glioblastoma multiforme KW - astrocytic tumor KW - expression pattern Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-123982 VL - 3 IS - 5 ER - TY - JOUR A1 - Jahed, Razieh Rafiei A1 - Kavousi, Mohammad Reza A1 - Farashiani, Mohammad Ebrahim A1 - Sagheb-Talebi, Khosro A1 - Babanezhad, Manoochehr A1 - Courbaud, Benoit A1 - Wirtz, Roland A1 - Müller, Jörg A1 - Larrieu, Laurent T1 - A comparison of the formation rates and composition of tree-related microhabitats in beech-dominated primeval Carpathian and Hyrcanian forests JF - Forests N2 - Primeval forests in the temperate zone exist only as a few remnants, but theses serve as important reference areas for conservation. As key habitats, tree-related microhabitats (TreMs) are of intense interest to forest ecologists, but little is known about their natural composition and dynamics in different tree species. Beech forms a major part of the temperate forests that extend from Europe, home to European beech Fagus sylvatica L. (Fs), eastward to Iran, where Oriental beech Fagus orientalis Lipsky (Fo) is the dominant species. In this study, we compared TreMs in primeval forests of both species, using data from Fo growing in 25 inventory plots throughout the Hyrcanian forest belt in Iran and from Fs growing in a 9 ha permanent plot in the Uholka Forest of Ukraine. TreMs based on 47 types and 11 subgroups were recorded. Beech trees in the Hyrcanian forest had a higher mean diameter at breast height (dbh) than beech trees in Uholka and contained twice as many TreMs per hectare. Although the mean richness of TreMs per TreM bearing tree was similar in the two species, on the basis of the comparison single trees in two groups (n = 405 vs. 2251), the composition of the TreMs clearly differed, as the proportions of rot holes, root-buttress concavities, and crown deadwood were higher in the Hyrcanian Forest, and those of bark losses, exposed heartwood, and burrs and cankers higher in Uholka Forest. Estimates of TreMs dynamics based on dbh and using Weibull models showed a significantly faster cumulative increase of TreMs in Fo, in which saturation occurred already in trees with a dbh of 70–80 cm. By contrast, the increase in TreMs in Fs was continuous. In both species, the probability density was highest at a dbh of about 30 cm, but was twice as high in Fo. Because of limitations of our study design, the reason behind observed differences of TreM formation and composition between regions remains unclear, as it could be either result of the tree species or the environment, or their interaction. However, the observed differences were more likely the result of differences in the environment than in the two tree species. Nevertheless, our findings demonstrate that the Hyrcanian Forest, recently designated as a natural heritage site in Iran, is unique, not only as a tertiary relict or due to its endemic trees, herbs and arthropods, but also because of its TreMs, which form a distinct and rich habitat for associated taxa, including endemic saproxylic species. KW - TreMs KW - Fagus orientalis KW - Fagus sylvatica KW - primeval forest Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-200849 SN - 1999-4907 VL - 11 IS - 2 ER - TY - THES A1 - Beer, Katharina T1 - A Comparison of the circadian clock of highly social bees (\(Apis\) \(mellifera\)) and solitary bees (\(Osmia\) \(spec.\)): Circadian clock development, behavioral rhythms and neuroanatomical characterization of two central clock components (PER and PDF) T1 - Ein Vergleich der Inneren Uhr von sozialen Bienen (\(Apis\) \(mellifera\)) und solitären Bienen (\(Osmia\) \(spec.\)): Entwicklung der circadianen Uhr, Verhaltensrhythmen und neuroanatomische Beschreibung von zwei zentralen Uhr Komponenten (PER und PDF) N2 - Summary Bees, like many other organisms, evolved an endogenous circadian clock, which enables them to foresee daily environmental changes and exactly time foraging flights to periods of floral resource availability. The social lifestyle of a honey bee colony has been shown to influence circadian behavior in nurse bees, which do not exhibit rhythmic behavior when they are nursing. On the other hand, forager bees display strong circadian rhythms. Solitary bees, like the mason bee, do not nurse their offspring and do not live in hive communities, but face the same daily environmental changes as honey bees. Besides their lifestyle mason and honey bees differ in their development and life history, because mason bees overwinter after eclosion as adults in their cocoons until they emerge in spring. Honey bees do not undergo diapause and have a relatively short development of a few weeks until they emerge. In my thesis, I present a comparison of the circadian clock of social honey bees (Apis mellifera) and solitary mason bees (Osmia bicornis and Osmia cornuta) on the neuroanatomical level and behavioral output level. I firstly characterized in detail the localization of the circadian clock in the bee brain via the expression pattern of two clock components, namely the clock protein PERIOD (PER) and the neuropeptide Pigment Dispersing Factor (PDF), in the brain of honey bee and mason bee. PER is localized in lateral neuron clusters (which we called lateral neurons 1 and 2: LN1 and LN2) and dorsal neuron clusters (we called dorsal lateral neurons and dorsal neurons: DLN, DN), many glia cells and photoreceptor cells. This expression pattern is similar to the one in other insect species and indicates a common ground plan of clock cells among insects. In the LN2 neuron cluster with cell bodies located in the lateral brain, PER is co-expressed with PDF. These cells build a complex arborization network throughout the brain and provide the perfect structure to convey time information to brain centers, where complex behavior, e.g. sun-compass orientation and time memory, is controlled. The PDF arborizations centralize in a dense network (we named it anterio-lobular PDF hub: ALO) which is located in front of the lobula. In other insects, this fiber center is associated with the medulla (accessory medulla: AME). Few PDF cells build the ALO already in very early larval development and the cell number and complexity of the network grows throughout honey bee development. Thereby, dorsal regions are innervated first by PDF fibers and, in late larval development, the fibers grow laterally to the optic lobe and central brain. The overall expression pattern of PER and PDF are similar in adult social and solitary bees, but I found a few differences in the PDF network density in the posterior protocerebrum and the lamina, which may be associated with evolution of sociality in bees. Secondly, I monitored activity rhythms, for which I developed and established a device to monitor locomotor activity rhythms of individual honey bees with contact to a mini colony in the laboratory. This revealed new aspects of social synchronization and survival of young bees with indirect social contact to the mini colony (no trophalaxis was possible). For mason bees, I established a method to monitor emergence and locomotor activity rhythms and I could show that circadian emergence rhythms are entrainable by daily temperature cycles. Furthermore, I present the first locomotor activity rhythms of solitary bees, which show strong circadian rhythms in their behavior right after emergence. Honey bees needed several days to develop circadian locomotor rhythms in my experiments. I hypothesized that honey bees do not emerge with a fully matured circadian system in the hive, while solitary bees, without the protection of a colony, would need a fully matured circadian clock right away after emergence. Several indices in published work and preliminary studies support my hypothesis and future studies on PDF expression in different developmental stages in solitary bees may provide hard evidence. N2 - Zusammenfassung Bienen, sowie viele andere Organismen, evolvierten eine innere circadiane Uhr, die es ihnen ermöglicht, tägliche Umweltveränderungen voraus zu sehen und ihre Foragierflüge zu Tageszeiten durchzuführen, wenn sie möglichst viele Blüten besuchen können. Es zeigte sich, dass der soziale Lebensstil der Honigbiene Einfluss auf das rhythmische Verhalten der Ammenbienen hat, die während der Brutpflege keinen täglichen Rhythmus im Verhalten aufweisen. Sammlerbienen auf der anderen Seite zeigen ein stark rhythmisches Verhalten. Solitäre Bienen, wie die Mauerbiene, betreiben keine Brutpflege und leben nicht in einer Staatengemeinschaft, aber sind den gleichen Umweltveränderungen ausgesetzt. Nicht nur Lebensstil, sondern auch Entwicklung und Lebenszyklus unterscheiden sich zwischen Honig- und Mauerbienen. Mauerbienen überwintern als adulte Insekten in einem Kokon bis sie im Frühjahr schlüpfen. Honigbienen durchleben keine Diapause und schlüpfen nach wenigen Wochen der Entwicklung im Bienenstock. In meiner Dissertation vergleiche ich die circadiane Uhr von sozialen Honigbienen (Apis mellifera) und solitären Mauerbienen (Osmia bicornis und Osmia cornuta) auf Ebene der Neuroanatomie und das durch die innere Uhr verursachte rhythmische Verhalten. Erstens charakterisierte ich detailliert die Lage der circadianen Uhr im Gehirn von Honig- und Mauerbiene anhand des Expressionsmusters von zwei Uhrkomponenten. Diese sind das Uhrprotein PERIOD (PER) und das Neuropeptid Pigment Dispersing Factor (PDF). PER wird exprimiert in lateralen Neuronen-Gruppen (die wir laterale Neurone 1 und 2 nannten: LN1 und LN2) und dorsalen Neuronen-Gruppen (benannt dorsal laterale Neurone und dorsale Neurone: DLN und DN), sowie in vielen Gliazellen und Fotorezeptorzellen. Dieses Expressionsmuster liegt ähnlich in anderen Insektengruppen vor und deutet auf einen Grundbauplan der Inneren Uhr im Gehirn von Insekten hin. In der LN2 Neuronen-Gruppe, deren Zellkörper im lateralen Gehirn liegen, sind PER und PDF in den gleichen Zellen co-lokalisiert. Diese Zellen bilden ein komplexes Netzwerk aus Verzweigungen durch das gesamte Gehirn und liefern damit die perfekte Infrastruktur, um Zeitinformation an Gehirnregionen weiterzuleiten, die komplexe Verhaltensweisen, wie Sonnenkompass-Orientierung und Zeitgedächtnis, steuern. Alle PDF Neuriten laufen in einer anterior zur Lobula liegenden Region zusammen (sie wurde ALO, anterio-lobular PDF Knotenpunkt, genannt). Dieser Knotenpunkt ist in anderen Insekten mit der Medulla assoziiert und wird akzessorische Medulla (AME) genannt. Wenige PDF Zellen bilden bereits im frühen Larvalstadium diesen ALO und die Zellzahl sowie die Komplexität des Netzwerks wächst die gesamte Entwicklung der Honigbiene hindurch. Dabei werden zuerst die dorsalen Gehirnregionen von PDF Neuronen innerviert und in der späteren Larvalentwicklung wachsen die Neurite lateral in Richtung der optischen Loben und des Zentralgehirns. Das generelle Expressionsmuster von PER und PDF in adulten sozialen und solitären Bienen ähnelt sich stark, aber ich identifizierte kleine Unterschiede in der PDF Netzwerkdichte im posterioren Protocerebrum und in der Lamina. Diese könnten mit der Evolution von sozialen Bienen assoziiert sein. Zweitens entwickelte und etablierte ich eine Methode, Lokomotionsrhythmen von individuellen Bienen im Labor aufzunehmen, die in Kontakt mit einem Miniaturvolk standen. Diese Methode enthüllte neue Aspekte der sozialen Synchronisation unter Honigbienen und des Überlebens von jungen Bienen, die indirekten sozialen Kontakt zu dem Miniaturvolk hatten (Trophalaxis war nicht möglich). Für Mauerbienen etablierte ich eine Methode Schlupf- und lokomotorische Aktivitätsrhythmik aufzuzeichnen und konnte damit zeigen, dass tägliche Rhythmen im Schlupf durch Synchronisation der circadianen Uhr in Mauerbienen durch Tagestemperatur-Zyklen erzielt werden kann. Des Weiteren präsentiere ich die ersten lokomotorischen Aktivitätsrhythmen von solitären Bienen, die sofort nach ihrem Schlupf einen starken circadianen Rhythmus im Verhalten aufwiesen. Honigbienen brauchten in meinen Experimenten mehrere Tage, um circadiane Rhythmen in Lokomotion zu entwickeln. Ich erstellte die Hypothese, dass Honigbienen zum Zeitpunkt des Schlupfes im Bienenvolk ein noch nicht vollständig ausgereiftes circadianes System besitzen, während solitäre Bienen, die ohne den Schutz eines Volkes sind, direkt nach dem Schlupf eine vollständig ausgereifte Uhr brauchen. Mehrere Hinweise in Publikationen und Vorversuchen unterstützen meine Hypothese. Zukünftige Studien der Entwicklung des PDF Neuronen-Netzwerkes in solitären Bienen unterschiedlicher Entwicklungsstufen könnten dies nachweisen. KW - Chronobiologie KW - circadian rhythms KW - honeybee KW - Mauerbiene KW - Neuroanatomie Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159765 ER - TY - JOUR A1 - Paelecke-Habermann, Yvonne A1 - Paelecke, Marko A1 - Mauth, Juliane A1 - Tschisgale, Juliane A1 - Lindenmeyer, Johannes A1 - Kübler, Andrea T1 - A comparison of implicit and explicit reward learning in low risk alcohol users versus people who binge drink and people with alcohol dependence JF - Addictive Behaviors Reports N2 - Chronic alcohol use leads to specific neurobiological alterations in the dopaminergic brain reward system, which probably are leading to a reward deficiency syndrome in alcohol dependence. The purpose of our study was to examine the effects of such hypothesized neurobiological alterations on the behavioral level, and more precisely on the implicit and explicit reward learning. Alcohol users were classified as dependent drinkers (using the DSM-IV criteria), binge drinkers (using criteria of the USA National Institute on Alcohol Abuse and Alcoholism) or low-risk drinkers (following recommendations of the Scientific board of trustees of the German Health Ministry). The final sample (n = 94) consisted of 36 low-risk alcohol users, 37 binge drinkers and 21 abstinent alcohol dependent patients. Participants were administered a probabilistic implicit reward learning task and an explicit reward- and punishment-based trial-and-error-learning task. Alcohol dependent patients showed a lower performance in implicit and explicit reward learning than low risk drinkers. Binge drinkers learned less than low-risk drinkers in the implicit learning task. The results support the assumption that binge drinking and alcohol dependence are related to a chronic reward deficit. Binge drinking accompanied by implicit reward learning deficits could increase the risk for the development of an alcohol dependence. KW - Alcohol dependence KW - Binge drinking KW - Low risk alcohol use KW - Implicit and explicit reward learning Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201406 VL - 9 ER - TY - JOUR A1 - Uhler, Johannes A1 - Haase, Peter A1 - Hoffmann, Lara A1 - Hothorn, Torsten A1 - Schmidl, Jürgen A1 - Stoll, Stefan A1 - Welti, Ellen A. R. A1 - Buse, Jörn A1 - Müller, Jörg T1 - A comparison of different Malaise trap types JF - Insect Conservation and Diversity N2 - Recent reports on insect decline have highlighted the need for long‐term data on insect communities towards identifying their trends and drivers. With the launch of many new insect monitoring schemes to investigate insect communities over large spatial and temporal scales, Malaise traps have become one of the most important tools due to the broad spectrum of species collected and reduced capture bias through passive sampling of insects day and night. However, Malaise traps can vary in size, shape, and colour, and it is unknown how these differences affect biomass, species richness, and composition of trap catch, making it difficult to compare results between studies. We compared five Malaise trap types (three variations of the Townes and two variations of the Bartak Malaise trap) to determine their effects on biomass and species richness as identified by metabarcoding. Insect biomass varied by 20%–55%, not strictly following trap size but varying with trap type. Total species richness was 20%–38% higher in the three Townes trap models compared to the Bartak traps. Bartak traps captured lower richness of highly mobile taxa but increased richness of ground‐dwelling taxa. The white roofed Townes trap captured a higher richness of pollinators. We find that biomass, total richness, and taxa group specific richness are all sensitive to Malaise trap type. Trap type should be carefully considered and aligned to match monitoring and research questions. Additionally, our estimates of trap type effects can be used to adjust results to facilitate comparisons across studies. KW - Bartak KW - biodiversity KW - insect communities KW - insect monitoring KW - Malaise trap KW - Townes KW - trap selectivity Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-293694 VL - 15 IS - 6 SP - 666 EP - 672 ER - TY - JOUR A1 - Duschl, Albert A1 - Jahn, Ute A1 - Bertling, Claudia A1 - Sebald, Walter T1 - A comparison of assays for the response of primary human T-cells upon stimulation with interleukin-2, interleukin-4 and interleukin-7 N2 - The most commonly used assay to quantitate the response of peripheral T~cells upon stimulation with growth factors is determination of incorporated (JH]TdR. We compared thls test to three other methods: 1. direct countlog of cells with a Coulter type counter as reference assay, 2. a colorimetric assay using the tetrazolium dye 3-[ 4,S-dimethylthiazol-l-yl]-2,5diphenyl tetrazolium (MTT), which is a cheap and increasingly popular non-radioactive method and 3. incorporation of the thymidine analog 5-bromo-2'-deoxyuridine detection with a monoclonal antibody on cytospins. Primary human PHA-blasts from >30 healthy individuals were stimulated with IL-2, IL-4 aod IL-7 and assayed with up to four different methods. We discuss the advantages and disadvantages of the assays used and tbe effects of differences between cell preparations. We observed no significant variations between individuals for the dose dependence, but the relative emctency of IL4 compared to IL-2 and IL-7 was variable. This was probably due to the slower response observed upon stimulation with this factor. KW - T-Lymphozyt KW - Interleukin 2 KW - Interleukin 4 KW - Interleukin 7 KW - T-cells KW - proliferation assays KW - IL-2 KW - IL-4 KW - IL-7 Y1 - 1992 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86750 ER - TY - JOUR A1 - Biscotti, Maria Assunta A1 - Adolfi, Mateus Contar A1 - Barucca, Marco A1 - Forconi, Mariko A1 - Pallavicini, Alberto A1 - Gerdol, Marco A1 - Canapa, Adriana A1 - Schartl, Manfred T1 - A comparative view on sex differentiation and gametogenesis genes in lungfish and coelacanths JF - Genome Biology and Evolution N2 - Gonadal sex differentiation and reproduction are the keys to the perpetuation of favorable gene combinations and positively selected traits. In vertebrates, several gonad development features that differentiate tetrapods and fishes are likely to be, at least in part, related to the water-to-land transition. The collection of information from basal sarcopterygians, coelacanths, and lungfishes, is crucial to improve our understanding of the molecular evolution of pathways involved in reproductive functions, since these organisms are generally regarded as “living fossils” and as the direct ancestors of tetrapods. Here, we report for the first time the characterization of >50 genes related to sex differentiation and gametogenesis in Latimeria menadoensis and Protopterus annectens. Although the expression profiles of most genes is consistent with the intermediate position of basal sarcopterygians between actinopterygian fish and tetrapods, their phylogenetic placement and presence/absence patterns often reveal a closer affinity to the tetrapod orthologs. On the other hand, particular genes, for example, the male gonad factor gsdf (Gonadal Soma-Derived Factor), provide examples of ancestral traits shared with actinopterygians, which disappeared in the tetrapod lineage. KW - sex differentiation KW - Latimeria menadoensis KW - Protopterus annectens KW - evolution KW - testis KW - gametogenesis KW - ovary Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176774 VL - 10 IS - 6 ER - TY - THES A1 - Karimi, Sohail Mehmood T1 - A Comparative Study on Guard Cell Function of the Glycophyte \(Arabidopsis\) \(thaliana\) and the Halophyte \(Thellungiella\) \(salsuginea\) Under Saline Growth Conditions T1 - Eine vergleichende Studie zur Schließzellfunktion des Glycophyten \(Arabidopsis\) \(thaliana\) und des Halophyten \(Thellungiella\) \(salsuginea\) unter salinen Wachstumsbedingungen N2 - The greatest problems faced during the 21st century is climate change which is a big threat to food security due to increasing number of people. The increase in extreme weather events, such as drought and heat, makes it difficult to cultivate conventional crops that are not stress tolerant. As a result, increasing irrigation of arable land leads to additional salinization of soils with plant-toxic sodium and chloride ions. Knowledge about the adaptation strategies of salt-tolerant plants to salt stress as well as detailed knowledge about the control of transpiration water loss of these plants are therefore important to guarantee productive agriculture in the future. In the present study, I have characterized salt sensitive and salt tolerant plant species at physiological, phenotypic and transcriptomic level under short (1x salt) and long-time (3x) saline growth conditions. Two approaches used for long-time saline growth conditions (i.e increasing saline conditions (3x salt) and constant high saline conditions (3x 200 mM salt) were successfully developed in the natural plant growth medium i.e soil. Salt sensitive plants, A. thaliana, were able to survive and successfully set seeds at the toxic concentrations on the increasing saline growth mediums, with minor changes in the phenotype. However, under constant high saline conditions they could not survive. This was due to keeping low potassium, and high salt ions (sodium and chloride) in the photosynthetic tissue i.e leaf. Similarly, high potassium and low salt ions in salt tolerant T. salsuginea on both saline environments were the key for survival of this plant species. Being salt tolerant, T. salsuginea always kept high potassium levels and low sodium (during 1x) and chloride levels (during both 1x and 3x) in the leaf tissue. A strict control over transpirational water loss via stomata (formed by pair of guard cells) is important to maintain plant water balance. Aperture size of the stomata is regulated by the turgidity of the guard cells. More turgid the guard cells, bigger the apertures are and hence more transpiration. Under osmotic stress, the water loss is reduced which was evident in the salt sensitive A. thaliana plants under both short and long-time saline growth conditions. As the osmotic stress was only increased during long time saline growth conditions in T. salsuginea therefore, water loss was also decreased only under these saline conditions. Environmental CO2 assimilation also takes place via stomata in plants which then is used for photosynthesis. Stomatal apertures also influence CO2 assimilation. As the light absorbing photosynthetic pigments were more affected in A. thaliana, therefore photosynthetic activity of the whole plant was also reduced. Similarly, both short and long-time saline growth conditions also reduced the effective quantum yield of A. thaliana guard cells. Growth of the plant is dependent on energy which comes from photosynthesis. Reduced environmental CO2 assimilation would affect photosynthesis and hence growth, which was clearly observed in A. thaliana guard cells under long-time saline growth conditions. Major differences in both guard cells types were observed in their chloride and potassium levels. Energy Dispersive X-Ray Analysis (EDXA) suggested strict control of chloride accumulation in T. salsuginea guard cells as the levels remain unchanged under all conditions. Similarly, use of sodium in place of potassium for osmotic adjustments seems to be dependent on Na+/K+ rations in both guard cell types. Increased salt ions and reduced potassium levels in A. thaliana guard cells posed negative effect on photochemistry which in turn increased ROS metabolism and reduced energy related pathways at transcriptomic level in this plant species. Moreover, photosynthesis was strongly affected in A. thaliana guard cells both at transcriptomic and physiological levels. Similarly, global phytohormones induced changes were more evident in A. thaliana guard cells especially on 3x salt medium. Among all phytohormones, genes under the control of auxin were more differentially expressed in A. thaliana guard cells which suggests wide changes in growth and development in this plant species under salinity. Phytohormone, ABA is vital for closing the stomata under abiotic stress conditions. Increased levels of ABA during saline conditions led to efflux of potassium and counter anions (chloride, malate, nitrate) from the guard cells which caused the outward flow of water and hence reduction in turgor pressure. Reduced turgor pressure led to reduced water loss and CO2 assimilation especially in A. thaliana. Guard cells of both plant species synthesized ABA during saline conditions which was reflected from transcriptomic data and ABA quantification in the guard cells. ABA induced signaling in both plant species varied at the ABA receptor (PYL/PYR) levels where totally contrasting responses were observed. PYL2, PYL8 and PYL9 were specific to A. thaliana, furthermore, PYL2 was found to be differentially expressed only under 3x salt growth conditions thus suggesting its role during long term salt stress in this plant species. Protein phosphatases, which negatively regulate ABA signaling on one hand and act as ABA sensor on the other hand were found to be more differentially expressed in A. thaliana than T. salsuginea guard cells, which suggests their diverse role in both plant species under saline conditions. Differential expression of more ABA signaling players in long time saline conditions was prominent which could be because of darkness, as it is well known that rapid closure of stomata under dark conditions require ABA signaling. Moreover, representation of these components in dark also suggests that plants become more sensitive to dark under saline conditions which is also evident from the transpiration rates. Altogether, increased salt ions in A. thaliana guard cells and leaves led to pigment degradation and ABA induced reduction in transpiration which in turn influenced its growth. In contrast, T. salsuginea is the salt excluder and therefore keeps low levels of salt ions especially the chloride both in leaves and guard cells which mildly affects its growth. Guard cells of A. thaliana encounter severe energy problems at physiological and transcriptomic level. Main differences in the ABA signalling between both plant species were observed at the ABA receptor level. N2 - Das größte Problem des 21. Jahrhunderts ist der Klimawandel, der aufgrund der wachsenden Zahl von Menschen eine große Bedrohung für die Ernährungssicherheit darstellt. Die Zunahme extremer Wetterereignisse wie Dürre und Hitze erschwert den Anbau konventioneller, nicht stressresistenter Pflanzen. Eine zunehmende Bewässerung von Ackerland führt daher zu einer zusätzlichen Versalzung der Böden mit pflanzentoxischen Natrium- und Chloridionen. Kenntnisse über die Anpassungsstrategien salztoleranter Pflanzen an Salzstress sowie detaillierte Kenntnisse über die Kontrolle des Wasserverlusts durch Transpiration dieser Pflanzen sind daher wichtig, um eine produktive Landwirtschaft auch in Zukunft zu gewährleisten. In der vorliegenden Studie habe ich salzempfindliche und salztolerante Pflanzenarten auf physiologischer, phänotypischer und transkriptioneller Ebene unter kurzen (1x Salz) und langen (3x) Salzwachstumsbedingungen charakterisiert. In dem natürlichen Pflanzenwachstumsmedium, dh. dem Boden, wurden zwei Ansätze erfolgreich entwickelt, die für lang anhaltende Salzwachstumsbedingungen (dh zunehmende Salzbedingungen (3x Salz) und konstant hohe Salzbedingungen (3x 200 mM Salz) verwendet wurden. Die Pflanzen waren in der Lage, Samen bei den toxischen Konzentrationen auf den ansteigenden Salzwachstumsmedien zu überleben und erfolgreich zu setzen, wobei geringfügige Änderungen des Phänotyps auftraten. Unter konstant hohen Salzbedingungen konnten sie jedoch nicht überleben. Dies lag daran, dass wenig Kalium und hohe Salzionen vorhanden waren (Natrium und Chlorid) im photosynthetischen Gewebe, dh im Blatt. Ebenso stellten hohe Kalium- und niedrige Salzionen in salztoleranten T. salsuginea in beiden salzhaltigen Umgebungen den Schlüssel zum Überleben dieser Pflanzenart dar. Da T. salsuginea salztolerant war, blieb der Kaliumspiegel stets hoch und der Natrium- (während 1x) und Chloridspiegel (während 1x und 3x) im Blattgewebe niedrig. Eine strikte Kontrolle des transpirationelen Wasserverlusts über Stomata (gebildet von zwei Schließzellen) ist wichtig, um den Wasserhaushalt der Pflanzen aufrechtzuerhalten. Die Öffnungsgröße der Stomata wird durch den Turgor der Schutzzellen reguliert. Je praller die Schließzellen, desto größer die Öffnungen und damit die Transpiration. Unter osmotischem Stress wird der Wasserverlust verringert, was bei den salzempfindlichen A. thaliana-Pflanzen sowohl unter kurz- als auch langfristigen Salzwachstumsbedingungen offensichtlich war. Da der osmotische Stress in T. salsuginea nur über einen langen Zeitraum unter Salzwachstumsbedingungen anstieg, verringerte sich auch der Wasserverlust nur unter diesen Salzbedingungen. Die Aufnahme von CO2 in die Umwelt erfolgt auch über die Stomata und wird dann für die Photosynthese verwendet. Stomata beeinflussen daher auch die CO2-Assimilation. Da die lichtabsorbierenden photosynthetischen Pigmente in A. thaliana stärker betroffen waren, war auch die photosynthetische Aktivität der gesamten Pflanze verringert. In ähnlicher Weise verringerten sowohl kurz- als auch langzeitige Salzwachstumsbedingungen auch die effektive Quantenausbeute von A. thaliana-Schließzellen. Das Wachstum der Pflanze hängt von der Energie ab, die aus der Photosynthese stammt. Eine verringerte CO2-Assimilation aus der Umwelt würde die Photosynthese und damit das Wachstum beeinträchtigen, was bei A. thaliana-Schließzellenn unter lang andauerenden Salzwachstumsbedingungen deutlich zu beobachten war. Wesentliche Unterschiede bei beiden Schließzelltypen wurden in ihren Chlorid- und Kaliumspiegeln beobachtet. Die energiedispersive Röntgenanalyse (EDXA) ergab eine strikte Kontrolle der Chloridakkumulation in T. salsuginea Schließzellen, da die Chloridkonzentrationen unter allen Bedingungen unverändert bleiben. In ähnlicher Weise scheint die Verwendung von Natrium anstelle von Kalium für osmotische Anpassungen von Na + / K + -Verhältnissen in beiden Schließzelltypen abhängig zu sein. Erhöhte Salzionen und verringerte Kaliumspiegel in A. thaliana-Schließzellen wirkten sich negativ auf die Photochemie aus, was wiederum den ROS-Metabolismus erhöhte und die energiebezogenen Wege auf transkriptomischem Niveau bei dieser Pflanzenart verringerte. Darüber hinaus war die Photosynthese in A. thaliana-Schließzellen sowohl auf transkriptioneller als auch auf physiologischer Ebene stark beeinträchtigt. In ähnlicher Weise waren globale Phytohormon-induzierte Veränderungen in A. thaliana-Schließzellen, insbesondere auf 3 × Salzmedium, deutlicher. Unter allen Phytohormonen wurden Gene unter der Kontrolle von Auxin in A. thaliana-Schließzellen differenzierter exprimiert, was auf weitreichende Veränderungen im Wachstum und in der Entwicklung dieser Pflanzenart unter Salzgehalt hindeutet. Das Phytohormon ABA ist für das Schließen der Stomata unter abiotischen Stressbedingungen von entscheidender Bedeutung. Erhöhte ABA-Spiegel unter Salzbedingungen führten zum Austritt von Kalium und Gegenanionen (Chlorid, Malat, Nitrat) aus den Schließzellen, was den Wasserfluss nach außen und damit eine Verringerung des Turgordrucks bewirkte. Reduzierter Turgordruck führte insbesondere bei A. thaliana zu einem geringeren Wasserverlust und einer geringeren CO2-Aufnahme. Die Schließzellen beider Pflanzenarten synthetisierten ABA unter Salzbedingungen, was sich aus den Transkriptomdaten und der ABA-Quantifizierung in den Schließzellen widerspiegelte. Die ABA-induzierte Signalübertragung in beiden Pflanzenarten variierte bei den ABA-Rezeptor- (PYL / PYR-) Spiegeln, bei denen völlig unterschiedliche Reaktionen beobachtet wurden. PYL2, PYL8 und PYL9 waren spezifisch für A. thaliana. Darüber hinaus wurde festgestellt, dass PYL2 nur unter dreifachen Salzwachstumsbedingungen unterschiedlich exprimiert wird, was auf seine Rolle bei langfristigem Salzstress bei dieser Pflanzenart hindeutet. Es wurde gefunden, dass Proteinphosphatasen, die einerseits die ABA-Signalübertragung negativ regulieren und andererseits als ABA-Sensor wirken, in A. thaliana differenzierter exprimiert werden als in T. salsuginea-Schließzellen, was auf ihre vielfältige Rolle in beiden Pflanzenarten unter Salzbedingungen hindeutet. Eine differenzierte Expression von mehr ABA-Signalgebern unter Bedingungen mit langer Salzwasserbewässerung war auffällig, was auf Dunkelheit zurückzuführen sein könnte, da bekanntlich ein schnelles Schließen der Stomata unter dunklen Bedingungen eine ABA-Signalgebung erfordert. Darüber hinaus deutet die Darstellung dieser Komponenten im Dunkeln auch darauf hin, dass Pflanzen unter salzhaltigen Bedingungen empfindlicher gegenüber Dunkelheit werden, was auch aus den Transpirationsraten hervorgeht. Insgesamt führten erhöhte Salzionen in A. thaliana-Schließzzellen und Blättern zu einem Pigmentabbau und einer durch ABA verursachten Reduktion der Transpiration, was deren Wachstum beeinflusste. Im Gegensatz dazu ist T. salsuginea in der Lage Salz auszuschließen und hält daher geringe Mengen an Salzionen, insbesondere das Chlorid sowohl in Blättern als auch in Schließzellen, dass sein Wachstum geringfügig beeinflusst. Schließzellen von A. thaliana stoßen auf physiologischer und transkriptomischer Ebene auf schwerwiegende Energieprobleme. Hauptunterschiede in der ABA-Signalgebung zwischen beiden Pflanzenarten wurden auf der ABA-Rezeptorebene beobachtet. KW - Glycophyten KW - Halophyten KW - salinen Wachstumsbedingungen KW - Schließzellfunktion KW - Transkriptomik anlyze KW - Halophytes KW - glycophytes KW - salt stress KW - guard cells KW - transcriptomic analysis Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-190942 ER - TY - JOUR A1 - Knorr, Johannes A1 - Rudolf, Philipp A1 - Nuernberger, Patrick T1 - A comparative study on chirped-pulse upconversion and direct multichannel MCT detection N2 - A comparative study is carried out on two spectroscopic techniques employed to detect ultrafast absorption changes in the mid-infrared spectral range, namely direct multichannel detection via HgCdTe (MCT) photodiode arrays and the newly established technique of chirped-pulse upconversion (CPU). Whereas both methods are meanwhile individually used in a routine manner, we directly juxtapose their applicability in femtosecond pump-probe experiments based on 1 kHz shot-to-shot data acquisition. Additionally, we examine different phase-matching conditions in the CPU scheme for a given mid-infrared spectrum, thereby simultaneously detecting signals which are separated by more than 200 cm−1. KW - Ultrafast spectroscopy KW - Upconversion KW - infrared spectroscopy KW - Lithium niobate KW - CCD, charge-coupled device Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111334 ER - TY - JOUR A1 - Jannasch, Maren A1 - Gaetzner, Sabine A1 - Weigel, Tobias A1 - Walles, Heike A1 - Schmitz, Tobias A1 - Hansmann, Jan T1 - A comparative multi-parametric in vitro model identifies the power of test conditions to predict the fibrotic tendency of a biomaterial JF - Scientific Reports N2 - Despite growing effort to advance materials towards a low fibrotic progression, all implants elicit adverse tissue responses. Pre-clinical biomaterial assessment relies on animals testing, which can be complemented by in vitro tests to address the Russell and Burch’s 3R aspect of reducing animal burden. However, a poor correlation between in vitro and in vivo biomaterial assessments confirms a need for suitable in vitro biomaterial tests. The aim of the study was to identify a test setting, which is predictive and might be time- and cost-efficient. We demonstrated how sensitive in vitro biomaterial assessment based on human primary macrophages depends on test conditions. Moreover, possible clinical scenarios such as lipopolysaccharide contamination, contact to autologous blood plasma, and presence of IL-4 in an immune niche influence the outcome of a biomaterial ranking. Nevertheless, by using glass, titanium, polytetrafluorethylene, silicone, and polyethylene representing a specific material-induced fibrotic response and by comparison to literature data, we were able to identify a test condition that provides a high correlation to state-of-the-art in vivo studies. Most important, biomaterial ranking obtained under native plasma test conditions showed a high predictive accuracy compared to in vivo assessments, strengthening a biomimetic three-dimensional in vitro test platform. KW - inflammation KW - experimental models of disease KW - biomaterial tests KW - in vitro Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170908 VL - 7 IS - 1689 ER - TY - THES A1 - Hauser, Anna Si-Lu T1 - A comparative approach to local organisation of the energy transition N2 - In recent years, numerous renewable energy cities were established worldwide, piloting different pathways to transition to clean energy. With the ability to address local needs more precisely in their unique geographic, social and economic contexts, cities play a vital role in implementing overall climate mitigation goals on the local level. In China, many renewable energy cities have emerged as well. However, official documents suggest that Chinese government authorities establish such renewable energy cities strategically, which leads to the assumption that the impulse to become renewable is different from other countries, where bottom-up initiatives are more common. Hence, this thesis explores answer to the question why and how the Chinese government promotes the energy transition of Chinese cities and regions. To explore the dynamics of local energy transition projects, this thesis adopts two frameworks from the field of sustainability transitions, the multi-level perspective and strategic niche management, and applies them to seven European and two Chinese case studies. The European sample includes the cities Graz, Güssing, Freiburg, and Helsinki as well as the communities Feldheim, Jühnde and Murau. The Chinese sample consists of the bottom-up initiative Shaanxi Sunflower Project and the demonstration project Tongli New Energy Town. A comparative analysis evaluates in how far the cases correspond to the multi-level perspective or strategic niche management. The comparison of the case studies reveals that the development of renewable energy cities in China goes beyond a top-down vs. bottom-up logic. In the Chinese context, strategic niche management should be understood as experimentation under hierarchy, which serves at pretesting different approaches before rolling them out nationwide. In addition, the analysis shows that both the multi-level perspective and strategic niche management have their advantages and disadvantages for niche development. Niches following the logic of the multi-level perspective may result in higher stakeholder acceptance, whereas strategic niche management can in turn accelerate niche development. However, since natural niche development cannot be steered intentionally, decision-makers who intend to induce local renewable energy projects have no other option but to resort to strategic niche management. To increase stakeholder acceptance and thus to improve the project outcome, decision-makers are advised to accommodate sufficient room for stakeholder participation in the project design. KW - China KW - multi-level perspective KW - strategic niche management KW - energy transition KW - top down KW - bottom up Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202109 ER - TY - JOUR A1 - Froudakis, G. A1 - Zdetsis, A. A1 - Mühlhäuser, M. A1 - Engels, Bernd A1 - Peyerimhoff, S. D. T1 - A comparative ab initio study of the Si\(_2\)C\(_4\), Si\(_3\)C\(_3\), Si\(_4\)C\(_2\) clusters N2 - Various structural possibilities for the Si\(_2\)C\(_4\) and Si\(_4\)C\(_2\) clusters are investigated by employing a basis set of triple-zeta plus polarization quality; electron correlation is generally accounted for by second-order M0ller-Plesset and, in certain instances, by higher-order perturbation (CASPT2) approaches. The building-up principle recently suggested from an analysis of Si\(_3\)C\(_3\) clusters is found to be fully operative for Si\(_2\)C\(_4\) and Si\(_4\)C\(_2\) clusters. A comparison of the structure and stability of various geometrical arrangements in the series C\(_6\) , Si\(_2\)C\(_4\) , Si\(_3\)C\(_3\) , Si\(_4\)C\(_2\), and Si\(_6\) shows that linear and planar structures become rapidly less stable if carbons are replaced by silicons and that the three-dimensional bipyramidal forms become less favorable as soon as silicons are exchanged by carbons in the parent Si\(_6\) structure. The effects can be rationalized in qualitative terms based on differences in silicon and carbon bonding. KW - Organische Chemie Y1 - 1994 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-59097 ER - TY - JOUR A1 - Ludwig, K. U. A1 - Sämann, P. A1 - Alexander, M. A1 - Becker, J. A1 - Bruder, J. A1 - Moll, K. A1 - Spieler, D. A1 - Czisch, M. A1 - Warnke, A. A1 - Docherty, S. J. A1 - Davis, O. S. P. A1 - Plomin, R. A1 - Nöthen, M. M. A1 - Landerl, K. A1 - Müller-Myhsok, B. A1 - Hoffmann, P. A1 - Schumacher, J. A1 - Schulte-Körne, G. A1 - Czamara, D. T1 - A common variant in Myosin-18B contributes to mathematical abilities in children with dyslexia and intraparietal sulcus variability in adults JF - Translational Psychiatry N2 - The ability to perform mathematical tasks is required in everyday life. Although heritability estimates suggest a genetic contribution, no previous study has conclusively identified a genetic risk variant for mathematical performance. Research has shown that the prevalence of mathematical disabilities is increased in children with dyslexia. We therefore correlated genome-wide data of 200 German children with spelling disability, with available quantitative data on mathematic ability. Replication of the top findings in additional dyslexia samples revealed that rs133885 was a genome-wide significant marker for mathematical abilities\((P_{comb}=7.71 x 10^{-10}, n=699)\), with an effect size of 4.87%. This association was also found in a sample from the general population (P=0.048, n=1080), albeit with a lower effect size. The identified variant encodes an amino-acid substitution in MYO18B, a protein with as yet unknown functions in the brain. As areas of the parietal cortex, in particular the intraparietal sulcus (IPS), are involved in numerical processing in humans, we investigated whether rs133885 was associated with IPS morphology using structural magnetic resonance imaging data from 79 neuropsychiatrically healthy adults. Carriers of the MYO18B risk-genotype displayed a significantly lower depth of the right IPS. This validates the identified association between rs133885 and mathematical disability at the level of a specific intermediate phenotype. KW - disability KW - sulcal morphology KW - prelevance KW - identification KW - brain KW - cancer KW - association KW - developmental dyscalculia KW - tumor-suppressor gene KW - correlate KW - disorders KW - dyscalculia KW - dyslexia KW - genomic imaging KW - mathematics KW - quantitative trait Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-131513 N1 - Supplementary Information accompanies the paper on the Translational Psychiatry website (http://www.nature.com/tp). VL - 3 IS - e229 ER - TY - THES A1 - Platt, Christian T1 - A Common Thread in Unconventional Superconductivity: The Functional Renormalization Group in Multi-Band Systems T1 - Unkonventionelle Supraleitung in Multi-Band Systemen N2 - Die supraleitenden Eigenschaften von komplexen Materialsystemen, wie den erst kürzlich entdeckten Eisen-Pniktiden oder den Strontium-Ruthenaten, sind oftmals durch das Zusammenspiel vieler elektronischer Orbitale bestimmt. Um die Supraleitung in derartigen Systemen besser zu verstehen, entwickeln wir in dieser Arbeit eine Multi-Orbital-Implementierung der funktionalen Renormierungsgruppe und untersuchen die Elektronenpaarung in verschiedenen charakteristischen Materialverbindungen. In den Eisen-Pniktiden finden wir hierbei mehrere Spinfluktuationskanäle, die eine Elektronenpaarung hervorrufen, sofern die Paarwellenfunktion einen Vorzeichenwechsel zwischen den verschiedenen genesteten Bereichen der Fermifläche aufweist. Abhängig von den spezifischen Materialeigenschaften, wie der Dotierung oder der Position des Pniktogenatoms, führen diese Spinfluktuationen dann zu $s_{\pm}$-wellenartiger Paarung mit durchgängiger Energielücke oder mit Knoten auf der Fermifläche. In manchen Fällen wird zudem auch $d$-wellenartige Paarung induziert, die in der Nähe des Übergangs zur $s_{\pm}$-Symmetrie einen gemischten $(s+id)$-Zustand mit gebrochener Zeitinversionssymmetrie aufweist. Diese neuartige Phase zeigt faszinierende Eigenschaften, wie zum Beispiel das spontane Entstehen von Supraströmen am Probenrand und um nichtmagnetische Störstellen. Auf Grund der durchgängigen Energielücke ist dieser $(s+id)$-Zustand energetisch begünstigt. Im Folgenden untersuchen wir zudem auch die elektronischen Instabilitäten eines weiteren außergewöhnlichen Materials -- dotiertes Graphen. Diese rein zweidimensionale Kohlenstoffverbindung ist schon seit mehreren Jahren im Fokus der Festkörperforschung und wurde mittlerweile auch durch neuartige experimentelle Verfahren dotiert, ohne die zugrundeliegende hexagonale Gittersturktur merklich zu stören. Eine theoretische Beschreibung dieses Systems erfordert die Berücksichtigung zweier nicht-equivalenter Gitterplätze, was wiederum effektiv als Zwei-Orbital-System aufgefasst werden kann. Durch die besondere Symmetrie der hexagonalen Gitterstruktur sind beide $d$-wellenartigen Paarungskanäle entartet und ahnlich der $(s+id)$-Paarung in den Pniktiden finden wir hier eine chirale $(d+id)$-Paarung in einem weiten Dotierungsbereich um van-Hove Füllung. Des Weiteren identifizieren wir Spin-Triplet-Paarung und eine exotische Form der Spindichtewelle, welche beide durch leichte Veränderung der langreichweitigen Hüpfamplituden und Wechselwirkungensparameter realisiert werden können. Als drittes Beispiel betrachten wir die Supraleitung in dem Strontium-Ruthenat Sr$_2$RuO$_4$. Die Besonderheit dieser Materialverbindung liegt in der möglichen Realisierung einer chiralen Spin-Triplet Paarung, die wiederum faszinierende Eigenschaften wie die Existenz von halbganzzahligen Flussvortizes mit nicht-Abelscher Vertauschungsstatistik aufweisen würde. Mittels eines mikroskopischen Drei-Orbital-Modells und der Berücksichtigung von Spin-Bahn-Kopplung finden wir hierbei, dass moderate ferromagnetische Spinfluktuationen immer noch ausreichen, um diesen speziellen Paarungszustand anzutreiben. Die berechnete Energielücke zeigt im Weiteren sehr starke Anisotropien auf dem $d_{xy}$-Orbital-dominierten Bereich der Fermifläche und verschwindet nahezu vollständig auf den anderen beiden Fermiflächen. N2 - The superconducting properties of complex materials like the recently discovered iron-pnictides or strontium-ruthenate are often governed by multi-orbital effects. In order to unravel the superconductivity of those materials, we develop a multi-orbital implementation of the functional renormalization group and study the pairing states of several characteristic material systems. Starting with the iron-pnictides, we find competing spin-fluctuation channels that become attractive if the superconducting gap changes sign between the nested portions of the Fermi surface. Depending on material details like doping or pnictogen height, these spin fluctuations then give rise to $s_{\pm}$-wave pairing with or without gap nodes and, in some cases, also change the symmetry to $d$-wave. Near the transition from nodal $s_{\pm}$-wave to $d$-wave pairing, we predict the occurrence of a time-reversal symmetry-broken $(s+id)$-pairing state which avoids gap nodes and is therefore energetically favored. We further study the electronic instabilities of doped graphene, another fascinating material which has recently become accessible and which can effectively be regarded as multi-orbital system. Here, the hexagonal lattice structure assures the degeneracy of two $d$-wave pairing channels, and the system then realizes a chiral $(d+id)$-pairing state in a wide doping range around van-Hove filling. In addition, we also find spin-triplet pairing as well as an exotic spin-density wave phase which both become leading if the long-ranged hopping or interaction parameters are slightly modified, for example, by choosing different substrate materials. Finally, we consider the superconducting state of strontium-ruthenate, a possible candidate for chiral spin-triplet pairing with fascinating properties like the existence of half-quantum vortices obeying non-Abelian statistics. Using a microscopic three orbital description including spin-orbit coupling, we demonstrate that ferromagnetic fluctuations are still sufficient to induce this $\bs{\hat{z}}(p_x\pm ip_y)$-pairing state. The resulting superconducting gap reveals strong anisotropies on the $d_{xy}$-dominated Fermi-surface pocket and nearly vanishes on the other remaining two pockets. KW - Supraleitung KW - Renormierungsgruppe KW - Eisen-basierte Supraleiter KW - iron-pnictides KW - ruthenates KW - graphene KW - multi-band superconductivity KW - functional renormalization group KW - Hochtemperatursupraleitung KW - Ruthenate KW - Pnictide Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-78824 ER - TY - JOUR A1 - Ziegler, Georg C. A1 - Ehlis, Ann-Christine A1 - Weber, Heike A1 - Vitale, Maria Rosaria A1 - Zöller, Johanna E. M. A1 - Ku, Hsing-Ping A1 - Schiele, Miriam A. A1 - Kürbitz, Laura I. A1 - Romanos, Marcel A1 - Pauli, Paul A1 - Kalisch, Raffael A1 - Zwanzger, Peter A1 - Domschke, Katharina A1 - Fallgatter, Andreas J. A1 - Reif, Andreas A1 - Lesch, Klaus-Peter T1 - A Common CDH13 Variant is Associated with Low Agreeableness and Neural Responses to Working Memory Tasks in ADHD JF - Genes N2 - The cell—cell signaling gene CDH13 is associated with a wide spectrum of neuropsychiatric disorders, including attention-deficit/hyperactivity disorder (ADHD), autism, and major depression. CDH13 regulates axonal outgrowth and synapse formation, substantiating its relevance for neurodevelopmental processes. Several studies support the influence of CDH13 on personality traits, behavior, and executive functions. However, evidence for functional effects of common gene variation in the CDH13 gene in humans is sparse. Therefore, we tested for association of a functional intronic CDH13 SNP rs2199430 with ADHD in a sample of 998 adult patients and 884 healthy controls. The Big Five personality traits were assessed by the NEO-PI-R questionnaire. Assuming that altered neural correlates of working memory and cognitive response inhibition show genotype-dependent alterations, task performance and electroencephalographic event-related potentials were measured by n-back and continuous performance (Go/NoGo) tasks. The rs2199430 genotype was not associated with adult ADHD on the categorical diagnosis level. However, rs2199430 was significantly associated with agreeableness, with minor G allele homozygotes scoring lower than A allele carriers. Whereas task performance was not affected by genotype, a significant heterosis effect limited to the ADHD group was identified for the n-back task. Heterozygotes (AG) exhibited significantly higher N200 amplitudes during both the 1-back and 2-back condition in the central electrode position Cz. Consequently, the common genetic variation of CDH13 is associated with personality traits and impacts neural processing during working memory tasks. Thus, CDH13 might contribute to symptomatic core dysfunctions of social and cognitive impairment in ADHD. KW - ADHD KW - CDH13 KW - neurodevelopment KW - executive functions KW - working memory KW - Big Five KW - agreeableness Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-245220 SN - 2073-4425 VL - 12 IS - 9 ER - TY - JOUR A1 - Kleikers, Pamela W. M. A1 - Hooijmans, Carlijn A1 - Göb, Eva A1 - Langhauser, Friederike A1 - Rewell, Sarah S. J. A1 - Radermacher, Kim A1 - Ritskes-Hoitinga, Merel A1 - Howells, David W. A1 - Kleinschnitz, Christoph A1 - Schmidt, Harald H. H. W. T1 - A combined pre-clinical meta-analysis and randomized confirmatory trial approach to improve data validity for therapeutic target validation JF - Scientific Reports N2 - Biomedical research suffers from a dramatically poor translational success. For example, in ischemic stroke, a condition with a high medical need, over a thousand experimental drug targets were unsuccessful. Here, we adopt methods from clinical research for a late-stage pre-clinical meta-analysis (MA) and randomized confirmatory trial (pRCT) approach. A profound body of literature suggests NOX\(_{2}\) to be a major therapeutic target in stroke. Systematic review and MA of all available NOX\(_{2}\)\(^{-/y}\) studies revealed a positive publication bias and lack of statistical power to detect a relevant reduction in infarct size. A fully powered multi-center pRCT rejects NOX\(_{2}\) as a target to improve neurofunctional outcomes or achieve a translationally relevant infarct size reduction. Thus stringent statistical thresholds, reporting negative data and a MA-pRCT approach can ensure biomedical data validity and overcome risks of bias. KW - focal cerebral ischemia KW - darbepoetin alpha KW - mice KW - translational stroke research KW - colony-stimulating factor KW - NADPH oxidase inhibitors KW - chronic kidney disease KW - diabetes mellitus KW - oxidative stress KW - search filter Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-151401 VL - 5 IS - 13428 ER - TY - JOUR A1 - Niewalda, Thomas A1 - Völler, Thomas A1 - Eschbach, Claire A1 - Ehmer, Julia A1 - Chou, Wen-Chuang A1 - Timme, Marc A1 - Fiala, André A1 - Gerber, Bertram T1 - A Combined Perceptual, Physico-Chemical, and ImagingApproach to ‘Odour-Distances’ Suggests a CategorizingFunction of the Drosophila Antennal Lobe N2 - How do physico-chemical stimulus features, perception, and physiology relate? Given the multi-layered and parallel architecture of brains, the question specifically is where physiological activity patterns correspond to stimulus features and/ or perception. Perceived distances between six odour pairs are defined behaviourally from four independent odour recognition tasks. We find that, in register with the physico-chemical distances of these odours, perceived distances for 3-octanol and n-amylacetate are consistently smallest in all four tasks, while the other five odour pairs are about equally distinct. Optical imaging in the antennal lobe, using a calcium sensor transgenically expressed in only first-order sensory or only second-order olfactory projection neurons, reveals that 3-octanol and n-amylacetate are distinctly represented in sensory neurons, but appear merged in projection neurons. These results may suggest that within-antennal lobe processing funnels sensory signals into behaviourally meaningful categories, in register with the physico-chemical relatedness of the odours. KW - Drosophila Antennal Lobe Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-74769 ER - TY - JOUR A1 - Niewalda, Thomas A1 - Völler, Thomas A1 - Eschbach, Claire A1 - Ehmer, Julia A1 - Wen-Chuang, Chou A1 - Timme, Marc A1 - Fiala, André A1 - Gerber, Bertram T1 - A Combined Perceptual, Physico-Chemical, and Imaging Approach to 'Odour-Distances' Suggests a Categorizing Function of the Drosophila Antennal Lobe JF - PLoS One N2 - How do physico-chemical stimulus features, perception, and physiology relate? Given the multi-layered and parallel architecture of brains, the question specifically is where physiological activity patterns correspond to stimulus features and/or perception. Perceived distances between six odour pairs are defined behaviourally from four independent odour recognition tasks. We find that, in register with the physico-chemical distances of these odours, perceived distances for 3octanol and n-amylacetate are consistently smallest in all four tasks, while the other five odour pairs are about equally distinct. Optical imaging in the antennal lobe, using a calcium sensor transgenically expressed in only first-order sensory or only second-order olfactory projection neurons, reveals that 3-octanol and n-amylacetate are distinctly represented in sensory neurons, but appear merged in projection neurons. These results may suggest that within-antennal lobe processing funnels sensory signals into behaviourally meaningful categories, in register with the physico-chemical relatedness of the odours. KW - organization KW - cameleon KW - honeybee KW - map KW - neurons KW - reveals KW - melanogaster KW - mushroom body KW - spatial representation KW - olfactory information Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133510 VL - 6 IS - 9 ER - TY - JOUR A1 - El-Kareh, Lydia A1 - Bihlmayer, Gustav A1 - Buchter, Arne A1 - Bentmann, Hendrik A1 - Blügel, Stefan A1 - Reinert, Friedrich A1 - Bode, Matthias T1 - A combined experimental and theoretical study of Rashba-split surface states on the ( √3x√3) Pb/Ag (111)R30° surface N2 - We report on a combined low-temperature scanning tunneling spectroscopy (STS), angle-resolved photoemission spectroscopy (ARPES), and density functional theory (DFT) investigation of the ( √3x√3) Pb/Ag (111)R30° surface alloy which provides a giant Rashba-type spin splitting. With STS we observed spectroscopic features that are assigned to two hole-like Rashba-split bands in the unoccupied energy range. By means of STS and quantum interference mapping we determine the band onsets, splitting strengths, and dispersions for both bands. The unambiguous assignment of scattering vectors is achieved by comparison to ARPES measurements. While intra-band scattering is found for both Rashba bands, inter-band scattering is only observed in the occupied energy range. Spin- and orbitally-resolved band structures were obtained by DFT calculations. Considering the scattering between states of different spin- and orbital character, the apparent deviation between experimentally observed scattering events and the theoretically predicted spin polarization could be resolved. KW - Rashba effect KW - spin–orbit coupling KW - scanning tunneling microscopy KW - angle resolved photo emission spectroscopy KW - density functional theory Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-112786 ER -