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Mathematische Semesterberichte - 相似文献
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Gürbüzbalaban Mert Ruszczyński Andrzej Zhu Landi 《Journal of Optimization Theory and Applications》2022,194(3):1014-1041
Journal of Optimization Theory and Applications - We consider a distributionally robust formulation of stochastic optimization problems arising in statistical learning, where robustness is with... 相似文献
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Positivity - We prove new characterisations of exponential stability for positive linear discrete-time systems in ordered Banach spaces, in terms of small-gain conditions. Such conditions have... 相似文献
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Human blood group A and B glycosyltransferases (GTA, GTB) are retaining glycosyltransferases, requiring a catalytic mechanism that conserves the anomeric configuration of the hexopyranose moiety of the donor substrate (UDP-GalNAc, UDP-Gal). Previous studies have shown that GTA and GTB cycle through structurally distinct states during catalysis. Here, we link binding and release of substrates, substrate-analogs, and products to transitions between open, semi-closed, and closed states of the enzymes. Methyl TROSY based titration experiments in combination with zz-exchange experiments uncover dramatic changes of binding kinetics associated with allosteric interactions between donor-type and acceptor-type ligands. Taken together, this highlights how allosteric control of on- and off-rates correlates with conformational changes, driving catalysis to completion. 相似文献
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Dr. Hua Tian Dr. Louis J. Sparvero Paul Blenkinsopp Dr. Andrew A. Amoscato Prof. Simon C. Watkins Prof. Hülya Bayır Prof. Valerian E. Kagan Prof. Nicholas Winograd 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(10):3188-3193
Millions of diverse molecules constituting the lipidome act as important signals within cells. Of these, cardiolipin (CL) and phosphatidylethanolamine (PE) participate in apoptosis and ferroptosis, respectively. Their subcellular distribution is largely unknown. Imaging mass spectrometry is capable of deciphering the spatial distribution of multiple lipids at subcellular levels. Here we report the development of a unique 70 keV gas-cluster ion beam that consists of (CO2)n+(n>10 000) projectiles. Coupled with direct current beam buncher-time-of-flight secondary-ion mass spectrometry, it is optimized for sensitivity towards high-mass species (up to m/z 3000) at high spatial resolution (1 μm). In combination with immunohistochemistry, phospholipids, including PE and CL, have been assessed in subcellular compartments of mouse hippocampal neuronal cells and rat brain tissue. 相似文献
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Peez Nadine Becker Jochen Ehlers Sonja M. Fritz Melanie Fischer Christian B. Koop Jochen H. E. Winkelmann Carola Imhof Wolfgang 《Analytical and bioanalytical chemistry》2019,411(28):7603-7603
Analytical and Bioanalytical Chemistry - The original version of this article contained a mistake. 相似文献
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Sultan Akhtar Şeyda Tuğba Günday B. Rabindran Jermy M.A. Almessiere Ayhan Bozkurt 《Journal of Saudi Chemical Society》2019,23(4):477-485
In this work, we report an efficient method to produce pure hollow silica spheres (HSS) using phenyltrimethoxysilane (PTMS) compound. The production of HSS was carried out via hydrolysis of PTMS in the aqueous media and followed by a condensation reaction to form silica spheres with phenyl groups. The product was then calcined to remove phenyl groups and obtain pure silica spheres with >95% fine structure. The chemical nature of pure silica was confirmed by Fourier transforms infrared spectroscopy. The calcined HSS were stable beyond the temperature of 900 °C as confirmed by thermal gravimetric analysis (TGA). The calcined spheres preserved their spherical appearance and hollow core as shown by SEM and TEM micrographs. Interestingly, the average size of the spheres was reduced significantly after calcination from 760 to 510 nm, confirming further the removal of phenyl groups. The calcined HSS offered much higher surface area (As) when analysed by BET; As for calcined product was ~406 and mere ~4.8 m2/g for uncalcined HSS. Finally, drug release study of cisplatin/HSS showed over 45% of steady cumulative release for 72 h. The prepared HSS can be dispersed in water opening the possibility of many novel bio/non-bio applications. 相似文献
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Dağlı Özge Köse Dursun Ali İçten Okan Avcı Gülçin Alp Şahin Onur 《Journal of Thermal Analysis and Calorimetry》2019,136(4):1467-1480
Journal of Thermal Analysis and Calorimetry - The coumarilate (coum?) and 1,10-phenanthroline (phen) mixed ligand complexes of Co(II) (1), Ni(II) (2) Cu(II) (3) and Zn(II) (4) were... 相似文献