TY - JOUR A1 - Paeth, Heiko A1 - Paxian, Andreas A1 - Sein, Dimitry V. A1 - Jacob, Daniela A1 - Panitz, Hans-Jürgen A1 - Warscher, Michael A1 - Fink, Andreas H. A1 - Kunstmann, Harald A1 - Breil, Marcus A1 - Engel, Thomas A1 - Krause, Andreas A1 - Toedter, Julian A1 - Ahrens, Bodo T1 - Decadal and multi-year predictability of the West African monsoon and the role of dynamical downscaling JF - Meteorologische Zeitschrift N2 - West African summer monsoon precipitation is characterized by distinct decadal variability. Due to its welldocumented link to oceanic boundary conditions in various ocean basins it represents a paradigm for decadal predictability. In this study, we reappraise this hypothesis for several sub-regions of sub-Saharan West Africa using the new German contribution to the coupled model intercomparison project phase 5 (CMIP5) near-term prediction system. In addition, we assume that dynamical downscaling of the global decadal predictions leads to an enhanced predictive skill because enhanced resolution improves the atmospheric response to oceanic forcing and landsurface feedbacks. Based on three regional climate models, a heterogeneous picture is drawn: none of the regional climate models outperforms the global decadal predictions or all other regional climate models in every region nor decade. However, for every test case at least one regional climate model was identified which outperforms the global predictions. The highest predictive skill is found in the western and central Sahel Zone with correlation coefficients and mean-square skill scores exceeding 0.9 and 0.8, respectively. KW - geography KW - decadal predictability KW - West Africa KW - monsoon rainfall KW - dynamical downscaling Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172018 VL - 26 IS - 4 ER - TY - JOUR A1 - Eckardt, Jan-Niklas A1 - Stasik, Sebastian A1 - Kramer, Michael A1 - Röllig, Christoph A1 - Krämer, Alwin A1 - Scholl, Sebastian A1 - Hochhaus, Andreas A1 - Crysandt, Martina A1 - Brümmendorf, Tim H. A1 - Naumann, Ralph A1 - Steffen, Björn A1 - Kunzmann, Volker A1 - Einsele, Hermann A1 - Schaich, Markus A1 - Burchert, Andreas A1 - Neubauer, Andreas A1 - Schäfer-Eckart, Kerstin A1 - Schliemann, Christoph A1 - Krause, Stefan W. A1 - Herbst, Regina A1 - Hänel, Mathias A1 - Frickhofen, Norbert A1 - Noppeney, Richard A1 - Kaiser, Ulrich A1 - Baldus, Claudia D. A1 - Kaufmann, Martin A1 - Rácil, Zdenek A1 - Platzbecker, Uwe A1 - Berdel, Wolfgang E. A1 - Mayer, Jiří A1 - Serve, Hubert A1 - Müller-Tidow, Carsten A1 - Ehninger, Gerhard A1 - Stölzel, Friedrich A1 - Kroschinsky, Frank A1 - Schetelig, Johannes A1 - Bornhäuser, Martin A1 - Thiede, Christian A1 - Middeke, Jan Moritz T1 - Loss-of-function mutations of BCOR are an independent marker of adverse outcomes in intensively treated patients with acute myeloid leukemia JF - Cancers N2 - Acute myeloid leukemia (AML) is characterized by recurrent genetic events. The BCL6 corepressor (BCOR) and its homolog, the BCL6 corepressor-like 1 (BCORL1), have been reported to be rare but recurrent mutations in AML. Previously, smaller studies have reported conflicting results regarding impacts on outcomes. Here, we retrospectively analyzed a large cohort of 1529 patients with newly diagnosed and intensively treated AML. BCOR and BCORL1 mutations were found in 71 (4.6%) and 53 patients (3.5%), respectively. Frequently co-mutated genes were DNTM3A, TET2 and RUNX1. Mutated BCORL1 and loss-of-function mutations of BCOR were significantly more common in the ELN2017 intermediate-risk group. Patients harboring loss-of-function mutations of BCOR had a significantly reduced median event-free survival (HR = 1.464 (95%-Confidence Interval (CI): 1.005–2.134), p = 0.047), relapse-free survival (HR = 1.904 (95%-CI: 1.163–3.117), p = 0.01), and trend for reduced overall survival (HR = 1.495 (95%-CI: 0.990–2.258), p = 0.056) in multivariable analysis. Our study establishes a novel role for loss-of-function mutations of BCOR regarding risk stratification in AML, which may influence treatment allocation. KW - acute myeloid leukemia KW - BCOR KW - BCORL1 KW - loss-of-function KW - risk stratification KW - survival Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236735 SN - 2072-6694 VL - 13 IS - 9 ER - TY - JOUR A1 - Dech, Stefan A1 - Holzwarth, Stefanie A1 - Asam, Sarah A1 - Andresen, Thorsten A1 - Bachmann, Martin A1 - Boettcher, Martin A1 - Dietz, Andreas A1 - Eisfelder, Christina A1 - Frey, Corinne A1 - Gesell, Gerhard A1 - Gessner, Ursula A1 - Hirner, Andreas A1 - Hofmann, Matthias A1 - Kirches, Grit A1 - Klein, Doris A1 - Klein, Igor A1 - Kraus, Tanja A1 - Krause, Detmar A1 - Plank, Simon A1 - Popp, Thomas A1 - Reinermann, Sophie A1 - Reiners, Philipp A1 - Roessler, Sebastian A1 - Ruppert, Thomas A1 - Scherbachenko, Alexander A1 - Vignesh, Ranjitha A1 - Wolfmueller, Meinhard A1 - Zwenzner, Hendrik A1 - Kuenzer, Claudia T1 - Potential and challenges of harmonizing 40 years of AVHRR data: the TIMELINE experience JF - Remote Sensing N2 - Earth Observation satellite data allows for the monitoring of the surface of our planet at predefined intervals covering large areas. However, there is only one medium resolution sensor family in orbit that enables an observation time span of 40 and more years at a daily repeat interval. This is the AVHRR sensor family. If we want to investigate the long-term impacts of climate change on our environment, we can only do so based on data that remains available for several decades. If we then want to investigate processes with respect to climate change, we need very high temporal resolution enabling the generation of long-term time series and the derivation of related statistical parameters such as mean, variability, anomalies, and trends. The challenges to generating a well calibrated and harmonized 40-year-long time series based on AVHRR sensor data flown on 14 different platforms are enormous. However, only extremely thorough pre-processing and harmonization ensures that trends found in the data are real trends and not sensor-related (or other) artefacts. The generation of European-wide time series as a basis for the derivation of a multitude of parameters is therefore an extremely challenging task, the details of which are presented in this paper. KW - AVHRR KW - Earth Observation KW - harmonization KW - time series analysis KW - climate related trends KW - automatic processing KW - Europe KW - TIMELINE Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-246134 SN - 2072-4292 VL - 13 IS - 18 ER - TY - JOUR A1 - Hanfstein, Benjamin A1 - Lauseker, Michael A1 - Hehlmann, Rüdiger A1 - Saussele, Susanne A1 - Erben, Philipp A1 - Dietz, Christian A1 - Fabarius, Alice A1 - Proetel, Ulrike A1 - Schnittger, Susanne A1 - Haferlach, Claudia A1 - Krause, Stefan W. A1 - Schubert, Jörg A1 - Einsele, Hermann A1 - Hänel, Mathias A1 - Dengler, Jolanta A1 - Falge, Christiane A1 - Kanz, Lothar A1 - Neubauer, Andreas A1 - Kneba, Michael A1 - Stengelmann, Frank A1 - Pfreundschuh, Michael A1 - Waller, Cornelius F. A1 - Spiekerman, Karsten A1 - Baerlocher, Gabriela M. A1 - Pfirrmann, Markus A1 - Hasford, Joerg A1 - Hofmann, Wolf-Karsten A1 - Hochhaus, Andreas A1 - Müller, Martin C. T1 - Distinct characteristics of e13a2 versus e14a2 BCR-ABL1 driven chronic myeloid leukemia under first-line therapy with imatinib JF - Haematologica N2 - The vast majority of chronic myeloid leukemia patients express a BCR-ABL1 fusion gene mRNA encoding a 210 kDa tyrosine kinase which promotes leukemic transformation. A possible differential impact of the corresponding BCR-ABL1 transcript variants e13a2 ("b2a2") and e14a2 ("b3a2") on disease phenotype and outcome is still a subject of debate. A total of 1105 newly diagnosed imatinib-treated patients were analyzed according to transcript type at diagnosis (e13a2, n=451; e14a2, n=496; e13a2+e14a2, n=158). No differences regarding age, sex, or Euro risk score were observed. A significant difference was found between e13a2 and e14a2 when comparing white blood cells (88 vs. 65 x 10(9)/L, respectively; P<0.001) and platelets (296 vs. 430 x 109/L, respectively; P<0.001) at diagnosis, indicating a distinct disease phenotype. No significant difference was observed regarding other hematologic features, including spleen size and hematologic adverse events, during imatinib-based therapies. Cumulative molecular response was inferior in e13a2 patients (P=0.002 for major molecular response; P<0.001 for MR4). No difference was observed with regard to cytogenetic response and overall survival. In conclusion, e13a2 and e14a2 chronic myeloid leukemia seem to represent distinct biological entities. However, clinical outcome under imatinib treatment was comparable and no risk prediction can be made according to e13a2 versus e14a2 BCR-ABL1 transcript type at diagnosis. (clinicaltrials.gov identifier: 00055874) KW - chronic myelogenous leukemia KW - polymerase-chain-reaktion KW - hybrid messenger RNA KW - chronic phase KW - cytogenetic response KW - no correlation KW - ABL gene KW - transcripts KW - breakpoint KW - survival Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115476 SN - 1592-8721 VL - 99 IS - 9 ER - TY - JOUR A1 - Saussele, Susanne A1 - Hehlmann, Ruediger A1 - Fabarius, Alice A1 - Jeromin, Sabine A1 - Proetel, Ulrike A1 - Rinaldetti, Sebastien A1 - Kohlbrenner, Katharina A1 - Einsele, Hermann A1 - Falge, Christine A1 - Kanz, Lothar A1 - Neubauer, Andreas A1 - Kneba, Michael A1 - Stegelmann, Frank A1 - Pfreundschuh, Michael A1 - Waller, Cornelius F. A1 - Oppliger Leibundgut, Elisabeth A1 - Heim, Dominik A1 - Krause, Stefan W. A1 - Hofmann, Wolf-Karsten A1 - Hasford, Joerg A1 - Pfirrmann, Markus A1 - Müller, Martin C. A1 - Hochhaus, Andreas A1 - Lauseker, Michael T1 - Defining therapy goals for major molecular remission in chronic myeloid leukemia: results of the randomized CML Study IV JF - Leukemia N2 - Major molecular remission (MMR) is an important therapy goal in chronic myeloid leukemia (CML). So far, MMR is not a failure criterion according to ELN management recommendation leading to uncertainties when to change therapy in CML patients not reaching MMR after 12 months. At monthly landmarks, for different molecular remission status Hazard ratios (HR) were estimated for patients registered to CML study IV who were divided in a learning and a validation sample. The minimum HR for MMR was found at 2.5 years with 0.28 (compared to patients without remission). In the validation sample, a significant advantage for progression-free survival (PFS) for patients in MMR could be detected (p-value 0.007). The optimal time to predict PFS in patients with MMR could be validated in an independent sample at 2.5 years. With our model we provide a suggestion when to define lack of MMR as therapy failure and thus treatment change should be considered. The optimal response time for 1% BCR-ABL at about 12-15 months was confirmed and for deep molecular remission no specific time point was detected. Nevertheless, it was demonstrated that the earlier the MMR is achieved the higher is the chance to attain deep molecular response later. KW - Chronic myeloid leukaemia KW - Molecularly targeted therapy KW - Risk factors KW - Risk factors KW - Translational research Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227528 VL - 32 IS - 5 ER - TY - JOUR A1 - Kraft, Andreas A1 - Stangl, Johannes A1 - Krause, Ana-Maria A1 - Müller-Buschbaum, Klaus A1 - Beuerle, Florian T1 - Supramolecular frameworks based on [60]fullerene hexakisadducts JF - Beilstein Journal of Organic Chemistry N2 - [60]Fullerene hexakisadducts possessing 12 carboxylic acid side chains form crystalline hydrogen-bonding frameworks in the solid state. Depending on the length of the linker between the reactive sites and the malonate units, the distance of the [60]fullerene nodes and thereby the spacing of the frameworks can be controlled and for the most elongated derivative, continuous channels are obtained within the structure. Stability, structural integrity and porosity of the material were investigated by powder X-ray diffraction, thermogravimetry and sorption measurements. KW - chemistry KW - fullerenes KW - hexakisadducts KW - hydrogen bonding KW - porous materials KW - structure elucidation Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171996 VL - 13 ER - TY - JOUR A1 - Proetel, Ulrike A1 - Pletsch, Nadine A1 - Lauseker, Michael A1 - Müller, Martin C. A1 - Hanfstein, Benjamin A1 - Krause, Stefan W. A1 - Kalmanti, Lida A1 - Schreiber, Annette A1 - Heim, Dominik A1 - Baerlocher, Gabriela M. A1 - Hofmann, Wolf-Karsten A1 - Lange, Elisabeth A1 - Einsele, Hermann A1 - Wernli, Martin A1 - Kremers, Stephan A1 - Schlag, Rudolf A1 - Müller, Lothar A1 - Hänel, Mathias A1 - Link, Hartmut A1 - Hertenstein, Bernd A1 - Pfirrmann, Markus A1 - Hochhaus, Andreas A1 - Hasford, Joerg A1 - Hehlmann, Rüdiger A1 - Saußele, Susanne T1 - Older patients with chronic myeloid leukemia (≥65 years) profit more from higher imatinib doses than younger patients: a subanalysis of the randomized CML-Study IV JF - Annals of Hematology N2 - The impact of imatinib dose on response rates and survival in older patients with chronic myeloid leukemia in chronic phase has not been studied well. We analyzed data from the German CML-Study IV, a randomized five-arm treatment optimization study in newly diagnosed BCR-ABL-positive chronic myeloid leukemia in chronic phase. Patients randomized to imatinib 400 mg/day (IM400) or imatinib 800 mg/day (IM800) and stratified according to age (≥65 years vs. <65 years) were compared regarding dose, response, adverse events, rates of progression, and survival. The full 800 mg dose was given after a 6-week run-in period with imatinib 400 mg/day. The dose could then be reduced according to tolerability. A total of 828 patients were randomized to IM400 or IM800. Seven hundred eighty-four patients were evaluable (IM400, 382; IM800, 402). One hundred ten patients (29 %) on IM400 and 83 (21 %) on IM800 were ≥65 years. The median dose per day was lower for patients ≥65 years on IM800, with the highest median dose in the first year (466 mg/day for patients ≥65 years vs. 630 mg/day for patients <65 years). Older patients on IM800 achieved major molecular remission and deep molecular remission as fast as younger patients, in contrast to standard dose imatinib with which older patients achieved remissions much later than younger patients. Grades 3 and 4 adverse events were similar in both age groups. Five-year relative survival for older patients was comparable to that of younger patients. We suggest that the optimal dose for older patients is higher than 400 mg/day. ClinicalTrials.gov identifier: NCT00055874 KW - chronic myeloid leukemia KW - older patients KW - different imatinib dose regimens KW - early applied higher imatinib dosages Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121574 SN - 0939-5555 VL - 93 IS - 7 ER - TY - JOUR A1 - Kleinert, Stefan A1 - Tony, Hans-Peter A1 - Krause, Andreas A1 - Feuchtenberger, Martin A1 - Wassenberg, Siegfried A1 - Richter, Constanze A1 - Röther, Ekkehard A1 - Spieler, Wolfgang A1 - Gnann, Holger A1 - Wittig, Bianca M. T1 - Impact of patient and disease characteristics on therapeutic success during adalimumab treatment of patients with rheumatoid arthritis: data from a German JF - Rheumatology International N2 - The objective of this study was to use data from a noninterventional study to evaluate the effectiveness of adalimumab in rheumatoid arthritis (RA) patients during routine clinical practice and to explore the potential impact of patient and disease characteristics in response to adalimumab therapy. A total of 2,625 RA patients with specified data at baseline (prior to initiating adalimumab treatment) and 12 months entered this study between April 2003 and March 2009. We evaluated response to adalimumab therapy and conducted stepwise regression and subgroup analyses of factors influencing therapeutic response. During the 1-year adalimumab treatment period, disease activity decreased from a baseline mean disease activity score-28 joints (DAS28) of 5.9–3.9, while functional capacity improved from 59.0 to 68.4 Funktionsfragebogen Hannover (FFbH) percentage points. In multivariate regression models, high baseline DAS28 was the strongest positive predictor for decrease in disease activity, and high baseline functional capacity was associated with reduced gains in functional capacity. Male gender was a positive predictor of therapeutic response for both disease activity and functional capacity, while older age and multiple previous biologics were associated with a reduced therapeutic response. Subset analyses provided further support for the impact of baseline DAS28, FFbH, and prior biologic therapy on therapeutic response during treatment. We conclude that treatment with adalimumab leads to decreased disease activity and improved function during routine clinical practice. Patients with high disease activity and low functional capacity are particularly benefitted by adalimumab therapy. KW - antirheumatic agents KW - adalimumab KW - rheumatoid arthritis KW - treatment outcome KW - regression analysis Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126220 VL - 32 IS - 9 ER - TY - JOUR A1 - Wendler, Jörg A1 - Burmester, Gerd R. A1 - Sörensen, Helmut A1 - Krause, Andreas A1 - Richter, Constanze A1 - Tony, Hans-Peter A1 - Rubbert-Roth, Andrea A1 - Bartz-Bazzanella, Peter A1 - Wassenberg, Siegfried A1 - Haug-Rost, Iris A1 - Dörner, Thomas T1 - Rituximab in patients with rheumatoid arthritis in routine practice (GERINIS): six-year results from a prospective, multicentre, non-interventional study in 2,484 patients JF - Arthritis Research & Therapy N2 - INTRODUCTION: The aim of this study was to evaluate the safety and efficacy of rituximab (RTX) in a large cohort of patients with rheumatoid arthritis in routine care, and to monitor changes in daily practice since the introduction of RTX therapy. METHODS: This was a multicentre, prospective, non-interventional study conducted under routine practice conditions in Germany. Efficacy was evaluated using Disease Activity Score in 28 joints (DAS28) and Health Assessment Questionnaire-Disability Index (HAQ-DI). Safety was assessed by recording adverse drug reactions (ADRs). Physician and patient global efficacy and tolerability assessments were also evaluated. RESULTS: Overall, 2,484 patients (76.7% female, mean age 56.4 years, mean disease duration 11.7 years) received RTX treatment (22.7% monotherapy). The total observation period was approximately six-years (median follow-up 14.7 months). RTX treatment led to improvements in DAS28 and HAQ-DI that were sustained over multiple courses. DAS28 improvements positively correlated with higher rheumatoid factor levels up to 50 IU/ml. Response and tolerability were rated good/very good by the majority of physicians and patients. Mean treatment intervals were 10.5 and 6.8 months for the first and last 400 enrolled patients, respectively. Infections were the most frequently reported ADRs (9.1%; 11.39/100 patient-years); approximately 1% of patients per course discontinued therapy due to ADRs. CONCLUSIONS: Prolonged RTX treatment in routine care is associated with good efficacy and tolerability, as measured by conventional parameters and by physicians' and patients' global assessments. Rheumatoid factor status served as a distinct and quantitative biomarker of RTX responsiveness. With growing experience, physicians repeated treatments earlier in patients with less severe disease activity. KW - Rituximab Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-121184 VL - 16 IS - 2 ER - TY - JOUR A1 - Kleinert, Stefan A1 - Tony, Hans-Peter A1 - Krause, Andreas A1 - Feuchtenberger, Martin A1 - Wassenberg, Siegfried A1 - Richter, Constanze A1 - Räther, Ekkehard A1 - Spieler, Wolfgang A1 - Gnann, Holger A1 - Wittig, Bianca M. T1 - Impact of patient and disease characteristics on therapeutic success during adalimumab treatment of patients with rheumatoid arthritis: data from a German noninterventional observational study JF - Rheumatology International N2 - The objective of this study was to use data from a noninterventional study to evaluate the effectiveness of adalimumab in rheumatoid arthritis (RA) patients during routine clinical practice and to explore the potential impact of patient and disease characteristics in response to adalimumab therapy. A total of 2,625 RA patients with specified data at baseline (prior to initiating adalimumab treatment) and 12 months entered this study between April 2003 and March 2009. We evaluated response to adalimumab therapy and conducted stepwise regression and subgroup analyses of factors influencing therapeutic response. During the 1-year adalimumab treatment period, disease activity decreased from a baseline mean disease activity score-28 joints (DAS28) of 5.9–3.9, while functional capacity improved from 59.0 to 68.4 Funktionsfragebogen Hannover (FFbH) percentage points. In multivariate regression models, high baseline DAS28 was the strongest positive predictor for decrease in disease activity, and high baseline functional capacity was associated with reduced gains in functional capacity. Male gender was a positive predictor of therapeutic response for both disease activity and functional capacity, while older age and multiple previous biologics were associated with a reduced therapeutic response. Subset analyses provided further support for the impact of baseline DAS28, FFbH, and prior biologic therapy on therapeutic response during treatment. We conclude that treatment with adalimumab leads to decreased disease activity and improved function during routine clinical practice. Patients with high disease activity and low functional capacity are particularly benefitted by adalimumab therapy. KW - antirheumatic agents KW - arthritis KW - adalimumab KW - rheumatoid KW - treatment outcome KW - regression analysis Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-125118 VL - 32 IS - 9 ER - TY - JOUR A1 - Mühlberg, Eric A1 - Umstätter, Florian A1 - Domhan, Cornelius A1 - Hertlein, Tobias A1 - Ohlsen, Knut A1 - Krause, Andreas A1 - Kleist, Christian A1 - Beijer, Barbro A1 - Zimmermann, Stefan A1 - Haberkorn, Uwe A1 - Mier, Walter A1 - Uhl, Philipp T1 - Vancomycin-lipopeptide conjugates with high antimicrobial activity on vancomycin-resistant enterococci JF - Pharmaceuticals N2 - Multidrug-resistant bacteria represent one of the most important health care problems worldwide. While there are numerous drugs available for standard therapy, there are only a few compounds capable of serving as a last resort for severe infections. Therefore, approaches to control multidrug-resistant bacteria must be implemented. Here, a strategy of reactivating the established glycopeptide antibiotic vancomycin by structural modification with polycationic peptides and subsequent fatty acid conjugation to overcome the resistance of multidrug-resistant bacteria was followed. This study especially focuses on the structure–activity relationship, depending on the modification site and fatty acid chain length. The synthesized conjugates showed high antimicrobial potential on vancomycin-resistant enterococci. We were able to demonstrate that the antimicrobial activity of the vancomycin-lipopeptide conjugates depends on the chain length of the attached fatty acid. All conjugates showed good cytocompatibility in vitro and in vivo. Radiolabeling enabled the in vivo determination of pharmacokinetics in Wistar rats by molecular imaging and biodistribution studies. An improved biodistribution profile in comparison to unmodified vancomycin was observed. While vancomycin is rapidly excreted by the kidneys, the most potent conjugate shows a hepatobiliary excretion profile. In conclusion, these results demonstrate the potential of the structural modification of already established antibiotics to provide highly active compounds for tackling multidrug-resistant bacteria. KW - antibiotics KW - multidrug-resistant bacteria KW - enterococci KW - vancomycin KW - structural modification KW - fatty acids KW - polycationic peptides Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-205879 SN - 1424-8247 VL - 13 IS - 6 ER - TY - JOUR A1 - Kim, Jin Hong A1 - Liess, Andreas A1 - Stolte, Matthias A1 - Krause, Ana-Maria A1 - Stepanenko, Vladimir A1 - Zhong, Chuwei A1 - Bialas, David A1 - Spano, Frank A1 - Würthner, Frank T1 - An Efficient Narrowband Near-Infrared at 1040 nm Organic Photodetector Realized by Intermolecular Charge Transfer Mediated Coupling Based on a Squaraine Dye JF - Advanced Materials N2 - A highly sensitive short-wave infrared (SWIR, λ > 1000 nm) organic photodiode (OPD) is described based on a well-organized nanocrystalline bulk-heterojunction (BHJ) active layer composed of a dicyanovinyl-functionalized squaraine dye (SQ-H) donor material in combination with PC\(_{61}\)BM. Through thermal annealing, dipolar SQ-H chromophores self-assemble in a nanoscale structure with intermolecular charge transfer mediated coupling, resulting in a redshifted and narrow absorption band at 1040 nm as well as enhanced charge carrier mobility. The optimized OPD exhibits an external quantum efficiency (EQE) of 12.3% and a full-width at half-maximum of only 85 nm (815 cm\(^{-1}\)) at 1050 nm under 0 V, which is the first efficient SWIR OPD based on J-type aggregates. Photoplethysmography application for heart-rate monitoring is successfully demonstrated on flexible substrates without applying reverse bias, indicating the potential of OPDs based on short-range coupled dye aggregates for low-power operating wearable applications. KW - squaraine dyes KW - crystal engineering KW - J-aggregates KW - near-infrared sensitivity KW - organic photodiodes Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-256374 VL - 33 IS - 26 ER - TY - JOUR A1 - Steininger, Michael A1 - Kobs, Konstantin A1 - Davidson, Padraig A1 - Krause, Anna A1 - Hotho, Andreas T1 - Density-based weighting for imbalanced regression JF - Machine Learning N2 - In many real world settings, imbalanced data impedes model performance of learning algorithms, like neural networks, mostly for rare cases. This is especially problematic for tasks focusing on these rare occurrences. For example, when estimating precipitation, extreme rainfall events are scarce but important considering their potential consequences. While there are numerous well studied solutions for classification settings, most of them cannot be applied to regression easily. Of the few solutions for regression tasks, barely any have explored cost-sensitive learning which is known to have advantages compared to sampling-based methods in classification tasks. In this work, we propose a sample weighting approach for imbalanced regression datasets called DenseWeight and a cost-sensitive learning approach for neural network regression with imbalanced data called DenseLoss based on our weighting scheme. DenseWeight weights data points according to their target value rarities through kernel density estimation (KDE). DenseLoss adjusts each data point’s influence on the loss according to DenseWeight, giving rare data points more influence on model training compared to common data points. We show on multiple differently distributed datasets that DenseLoss significantly improves model performance for rare data points through its density-based weighting scheme. Additionally, we compare DenseLoss to the state-of-the-art method SMOGN, finding that our method mostly yields better performance. Our approach provides more control over model training as it enables us to actively decide on the trade-off between focusing on common or rare cases through a single hyperparameter, allowing the training of better models for rare data points. KW - supervised learning KW - imbalanced regression KW - cost-sensitive learning KW - sample weighting KW - Kerneldensity estimation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-269177 SN - 1573-0565 VL - 110 IS - 8 ER - TY - JOUR A1 - Steininger, Michael A1 - Abel, Daniel A1 - Ziegler, Katrin A1 - Krause, Anna A1 - Paeth, Heiko A1 - Hotho, Andreas T1 - ConvMOS: climate model output statistics with deep learning JF - Data Mining and Knowledge Discovery N2 - Climate models are the tool of choice for scientists researching climate change. Like all models they suffer from errors, particularly systematic and location-specific representation errors. One way to reduce these errors is model output statistics (MOS) where the model output is fitted to observational data with machine learning. In this work, we assess the use of convolutional Deep Learning climate MOS approaches and present the ConvMOS architecture which is specifically designed based on the observation that there are systematic and location-specific errors in the precipitation estimates of climate models. We apply ConvMOS models to the simulated precipitation of the regional climate model REMO, showing that a combination of per-location model parameters for reducing location-specific errors and global model parameters for reducing systematic errors is indeed beneficial for MOS performance. We find that ConvMOS models can reduce errors considerably and perform significantly better than three commonly used MOS approaches and plain ResNet and U-Net models in most cases. Our results show that non-linear MOS models underestimate the number of extreme precipitation events, which we alleviate by training models specialized towards extreme precipitation events with the imbalanced regression method DenseLoss. While we consider climate MOS, we argue that aspects of ConvMOS may also be beneficial in other domains with geospatial data, such as air pollution modeling or weather forecasts. KW - Klima KW - Modell KW - Deep learning KW - Neuronales Netz KW - climate KW - neural networks KW - model output statistics Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324213 SN - 1384-5810 VL - 37 IS - 1 ER -