@phdthesis{Schmidt2011, author = {Schmidt, Marco}, title = {Ground Station Networks for Efficient Operation of Distributed Small Satellite Systems}, isbn = {978-3-923959-77-8}, doi = {10.25972/OPUS-4984}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-64999}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2011}, abstract = {The field of small satellite formations and constellations attracted growing attention, based on recent advances in small satellite engineering. The utilization of distributed space systems allows the realization of innovative applications and will enable improved temporal and spatial resolution in observation scenarios. On the other side, this new paradigm imposes a variety of research challenges. In this monograph new networking concepts for space missions are presented, using networks of ground stations. The developed approaches combine ground station resources in a coordinated way to achieve more robust and efficient communication links. Within this thesis, the following topics were elaborated to improve the performance in distributed space missions: Appropriate scheduling of contact windows in a distributed ground system is a necessary process to avoid low utilization of ground stations. The theoretical basis for the novel concept of redundant scheduling was elaborated in detail. Additionally to the presented algorithm was a scheduling system implemented, its performance was tested extensively with real world scheduling problems. In the scope of data management, a system was developed which autonomously synchronizes data frames in ground station networks and uses this information to detect and correct transmission errors. The system was validated with hardware in the loop experiments, demonstrating the benefits of the developed approach.}, subject = {Kleinsatellit}, language = {en} } @article{WohlfarthSchmitteckertHaertleetal.2017, author = {Wohlfarth, Carolin and Schmitteckert, Stefanie and H{\"a}rtle, Janina D. and Houghton, Lesley A. and Dweep, Harsh and Fortea, Marina and Assadi, Ghazaleh and Braun, Alexander and Mederer, Tanja and P{\"o}hner, Sarina and Becker, Philip P. and Fischer, Christine and Granzow, Martin and M{\"o}nnikes, Hubert and Mayer, Emeran A. and Sayuk, Gregory and Boeckxstaens, Guy and Wouters, Mira M. and Simr{\´e}n, Magnus and Lindberg, Greger and Ohlsson, Bodil and Schmidt, Peter Thelin and Dlugosz, Aldona and Agreus, Lars and Andreasson, Anna and D'Amato, Mauro and Burwinkel, Barbara and Bermejo, Justo Lorenzo and R{\"o}th, Ralph and Lasitschka, Felix and Vicario, Maria and Metzger, Marco and Santos, Javier and Rappold, Gudrun A. and Martinez, Cristina and Niesler, Beate}, title = {miR-16 and miR-103 impact 5-HT4 receptor signalling and correlate with symptom profile in irritable bowel syndrome}, series = {Scientific Reports}, volume = {7}, journal = {Scientific Reports}, doi = {10.1038/s41598-017-13982-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-173478}, year = {2017}, abstract = {Irritable bowel syndrome (IBS) is a gut-brain disorder involving alterations in intestinal sensitivity and motility. Serotonin 5-HT4 receptors are promising candidates in IBS pathophysiology since they regulate gut motor function and stool consistency, and targeted 5-HT4R selective drug intervention has been proven beneficial in subgroups of patients. We identified a single nucleotide polymorphism (SNP) (rs201253747) c.*61 T > C within the 5-HT4 receptor gene \(HTR4\) to be predominantly present in diarrhoea-IBS patients (IBS-D). It affects a binding site for the miR-16 family and miR-103/miR-107 within the isoforms \({HTR4b/i}\) and putatively impairs \(HTR4\) expression. Subsequent miRNA profiling revealed downregulation of miR-16 and miR-103 in the jejunum of IBS-D patients correlating with symptoms. \(In\) \(vitro\) assays confirmed expression regulation via three 3′UTR binding sites. The novel isoform \(HTR4b\_2\) lacking two of the three miRNA binding sites escapes miR-16/103/107 regulationin SNP carriers. We provide the first evidence that \(HTR4\) expression is fine-tuned by miRNAs, and that this regulation is impaired either by the SNP c.*61 T > C or bydiminished levels of miR-16 and miR-103 suggesting that \(HTR4\) might be involved in the development of IBS-D.}, language = {en} } @article{Trujillo‐VieraEl‐MerahbiSchmidtetal.2021, author = {Trujillo-Viera, Jonathan and El-Merahbi, Rabih and Schmidt, Vanessa and Karwen, Till and Loza-Valdes, Angel and Strohmeyer, Akim and Reuter, Saskia and Noh, Minhee and Wit, Magdalena and Hawro, Izabela and Mocek, Sabine and Fey, Christina and Mayer, Alexander E. and L{\"o}ffler, Mona C. and Wilhelmi, Ilka and Metzger, Marco and Ishikawa, Eri and Yamasaki, Sho and Rau, Monika and Geier, Andreas and Hankir, Mohammed and Seyfried, Florian and Klingenspor, Martin and Sumara, Grzegorz}, title = {Protein Kinase D2 drives chylomicron-mediated lipid transport in the intestine and promotes obesity}, series = {EMBO Molecular Medicine}, volume = {13}, journal = {EMBO Molecular Medicine}, number = {5}, doi = {10.15252/emmm.202013548}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-239018}, year = {2021}, abstract = {Lipids are the most energy-dense components of the diet, and their overconsumption promotes obesity and diabetes. Dietary fat content has been linked to the lipid processing activity by the intestine and its overall capacity to absorb triglycerides (TG). However, the signaling cascades driving intestinal lipid absorption in response to elevated dietary fat are largely unknown. Here, we describe an unexpected role of the protein kinase D2 (PKD2) in lipid homeostasis. We demonstrate that PKD2 activity promotes chylomicron-mediated TG transfer in enterocytes. PKD2 increases chylomicron size to enhance the TG secretion on the basolateral side of the mouse and human enterocytes, which is associated with decreased abundance of APOA4. PKD2 activation in intestine also correlates positively with circulating TG in obese human patients. Importantly, deletion, inactivation, or inhibition of PKD2 ameliorates high-fat diet-induced obesity and diabetes and improves gut microbiota profile in mice. Taken together, our findings suggest that PKD2 represents a key signaling node promoting dietary fat absorption and may serve as an attractive target for the treatment of obesity.}, language = {en} }