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941.
Jessica Mühlhaus Juliane Dinter Daniela Nürnberg Maren Rehders Maren Depke Janine Golchert Georg Homuth Chun-Xia Yi Silke Morin Josef K?hrle Klaudia Brix Matthias Tsch?p Gunnar Kleinau Heike Biebermann 《International journal of molecular sciences》2014,15(11):20638-20655
The thyroid hormone derivative 3-iodothyronamine (3-T1AM) exerts metabolic effects in vivo that contradict known effects of thyroid hormones. 3-T1AM acts as a trace amine-associated receptor 1 (TAAR1) agonist and activates Gs signaling in vitro. Interestingly, 3-T1AM-meditated in vivo effects persist in Taar1 knockout-mice indicating that further targets of 3-T1AM might exist. Here, we investigated another member of the TAAR family, the only scarcely studied mouse and human trace-amine-associated receptor 8 (Taar8b, TAAR8). By RT-qPCR and locked-nucleic-acid (LNA) in situ hybridization, Taar8b expression in different mouse tissues was analyzed. Functionally, we characterized TAAR8 and Taar8b with regard to cell surface expression and signaling via different G-protein-mediated pathways. Cell surface expression was verified by ELISA, and cAMP accumulation was quantified by AlphaScreen for detection of Gs and/or Gi/o signaling. Activation of G-proteins Gq/11 and G12/13 was analyzed by reporter gene assays. Expression analyses revealed at most marginal Taar8b expression and no gender differences for almost all analyzed tissues. In heart, LNA-in situ hybridization demonstrated the absence of Taar8b expression. We could not identify 3-T1AM as a ligand for TAAR8 and Taar8b, but both receptors were characterized by a basal Gi/o signaling activity, a so far unknown signaling pathway for TAARs. 相似文献
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943.
ZdenĚK Slanina Jean-Pierre FranÇlois Matthias Kolb Dirk Bakowies Walter Thiel 《Fullerenes, Nanotubes and Carbon Nanostructures》2013,21(2):221-230
C84 is treated as a system composed of 24 local minima whose energies, geometries, and vibrational frequencies are obtained from MNDO calculations. The predicted global minimum of D2d symmetry remains the most abundant species in the equilibrium isomeric mixture only till 276 K, being replaced by a D2 species beyond that point. However, a C 1 structure is prevalent in the high temperature limit. The calculated composition around a temperature of 1000 K is consistent with very recent NMR observations. 相似文献
944.
Knowledge of the atomic geometry of a surface is a prerequisite for any detailed understanding of the surface's electronic structure and chemical properties. Previous studies have convincingly demonstrated that density functional theory (DFT) yields accurate surface atomic geometries and that reliable predictions concerning stable and metastable phases can be made on the basis of the calculated energetics. In the present work, we use DFT to investigate the atomic structure of four ordered coadsorbate phases of carbon monoxide and oxygen on Ru (0001). All of the structures have a (2 × 2) periodicity with differing concentrations of CO molecules and O atoms. For two of these phases dynamical low-energy electron diffraction (LEED) intensity analyses have been performed, and the agreement between our DFT- and the LEED-determined structures is found to be very good. We predict the atomic geometry of the third phase, for which no structural determination based on experiments has been made to date. We also predict the stability of a new ordered mixed phase. 相似文献
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946.
Matthias Heymann Janet Martin‐Nielsen 《Centaurus; international magazine of the history of science and medicine》2013,55(3):221-242
With this introduction we aim to illuminate Western Europe's place on the map of Cold War science and, specifically, to draw attention to the differences in and the diversity of Western European Cold War science in comparison to the United States. By discussing narratives of Cold War science in small states and asking how they fit into the European condition, we suggest that the fact of being a small state affects the conditions for and the scope of Cold War science. As a whole, this special issue also emphasizes the importance of the spatial dimension; that is, the significant dependence of Cold War science on geographical relations and geopolitical interests. 相似文献
947.
Dr. Kathrin S. Braunwarth B. Sc. Matthias Kaiser B. Sc. Anna-Luisa Müller 《WIRTSCHAFTSINFORMATIK》2010,52(1):33-44
In the context of value and customer orientation there are various requirements concerning the process – especially in insurance companies: processes are meant to be standardized, automated, and flexible. It is in question whether a fast and cheap automated processing is preferred to manual handling. For which claims and which process steps is it of economic value to have the flexibility and the competence and ability to solve problems of human operators at your disposal? Various combinations, representing different degrees of automation, are possible. The different degrees of automation for the processing of an insurance claims are compared and resulting cash flows are determined. It is essential to include all consequences that can be attributed to a single process and to consider customer reactions and restrictions to the capacity of processing. Instead of using heuristic rules to decide on automation in practice, here the decision is flexible and depends on the given situation. Viewing an aggregated number of insurance claims it is possible to deduce information about the performance of the process. The model is exemplarily illustrated with help of a part of the process for handling own damage glass claims. 相似文献
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