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21.
Maa Mavri Katja Spiess Mette Marie Rosenkilde Catrin Sian Rutland Milka Vrecl Valentina Kubale 《Molecules (Basel, Switzerland)》2020,25(23)
Endocytosis is a fundamental process involved in trafficking of various extracellular and transmembrane molecules from the cell surface to its interior. This enables cells to communicate and respond to external environments, maintain cellular homeostasis, and transduce signals. G protein-coupled receptors (GPCRs) constitute a family of receptors with seven transmembrane alpha-helical domains (7TM receptors) expressed at the cell surface, where they regulate physiological and pathological cellular processes. Several herpesviruses encode receptors (vGPCRs) which benefits the virus by avoiding host immune surveillance, supporting viral dissemination, and thereby establishing widespread and lifelong infection, processes where receptor signaling and/or endocytosis seem central. vGPCRs are rising as potential drug targets as exemplified by the cytomegalovirus-encoded receptor US28, where its constitutive internalization has been exploited for selective drug delivery in virus infected cells. Therefore, studying GPCR trafficking is of great importance. This review provides an overview of the current knowledge of endocytic and cell localization properties of vGPCRs and methodological approaches used for studying receptor internalization. Using such novel approaches, we show constitutive internalization of the BILF1 receptor from human and porcine γ-1 herpesviruses and present motifs from the eukaryotic linear motif (ELM) resources with importance for vGPCR endocytosis. 相似文献
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Katja Fröhlich Evgeny Legotin Frank Bärhold Atanaska Trifonova 《Journal of Solid State Electrochemistry》2017,21(12):3403-3410
The spray roasting process is recently applied for production of catalysts and single metal oxides. In our study, it was adapted for large-scale manufacturing of a more complex mixed oxide system, in particular symmetric lithium nickel manganese cobalt oxide (LiNi1/3Co1/3Mn1/3O2—NMC), which is already used as cathode material in lithium-ion batteries. An additional lithiation step was coupled with the main process in order to obtain the desired layered structure. Thermogravimetric analysis and high-temperature X-ray diffractometry built the basis for determining suitable synthesis temperature regions for the used chloride precursors and the post-treatment step. The optimized process was proven on an industrial pilot line where a setup for minimum production capacity of 12 kg h?1 was possible. The powder obtained directly after roasting had a very striking morphology compared to the final lithiated product. Hollow aggregates (≥250 μm) with overall 10.926 m2 g?1 surface area and a pore diameter of 3.396 nm were observed. Their well-faceted primary particles were converted into nanosized spheres after lithiation, building a few micrometer big high-porous agglomerates. Actual composition was verified by inductively coupled plasma atomic emission spectroscopy analysis, and the crystal structure and corresponding unit cell parameters were identified and confirmed by Rietveld fit of the derived X-ray diffraction pattern. The initial electrochemical measurements show a 149-mAh g?1discharge capacity, as determined from cyclic voltammetry. 相似文献
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Katja Maass 《ZDM》2011,43(4):573-586
This paper describes a qualitative study that examines in more detail the question of how teachers’ beliefs may influence the intention to implement change as suggested by a professional development initiative. Several teachers in Germany took part in a professional development initiative for modelling. The course comprised five workshops spread over 2008. A part of our evaluation of the course involved interviewing six teachers after they had taken part. Teachers were interviewed about the impact the course had had on them, the opportunities and any related impediments they saw for modelling, and the way in which they typically taught. The interviews were evaluated using codes. Although the sample is very small, the cases allow for interesting insights, and for the hypotheses that teachers’ beliefs about effective teaching seem to have a major impact on whether or not they intend to change their classroom practice, as suggested by the professional development initiative, and on whether or not teachers perceive the context in which they are teaching (school head, parents, students, etc.) as supportive. 相似文献
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Network forming properties of various proteins adsorbed at the air/water interface in relation to foam stability 总被引:4,自引:0,他引:4
Martin AH Grolle K Bos MA Cohen Stuart MA van Vliet T 《Journal of colloid and interface science》2002,254(1):175-183
A series of proteins was studied with respect to their ability to form a network at the air/water interface and their suitability as foaming agents and foam stabilizers. Proteins were chosen with a range of structures from flexible to rigid/globular: beta-casein, beta-lactoglobulin, ovalbumin, and (soy) glycinin. Experiments were performed at neutral pH except for glycinin, which was studied at both pH 3 and pH 6.7. The adsorption process was followed with an automated drop tensiometer (ADT). Network forming properties were assessed in terms of surface dilational modulus (determined with the ADT), the critical falling film length (L(still)) and flow rate (Q(still)) below which a stagnant film exists (as measured with the overflowing cylinder technique), and the fracture stress and fracture strain measured in surface shear. It was found that glycinin (pH 3) can form an interfacial gel in a very short time, whereas beta-casein has very poor network-forming properties. Hardly any foam could be produced at the chosen conditions with glycinin (pH 6.7) and with ovalbumin, whereas beta-casein, beta-lactoglobulin, and glycinin (pH 3) were good foaming agents. It seems that adsorption and unfolding rate are most important for foam formation. Once the foam is formed, a rigid network might favor stabilizing the foam. 相似文献
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Derakhshan S Assoud A Kleinke KM Dashjav E Qiu X Billinge SJ Kleinke H 《Journal of the American Chemical Society》2004,126(26):8295-8302
The new binary antimonide Ti(2)Sb was found to crystallize in a distorted variant of the La(2)Sb type, which contains a square planar La net with short La-La bonds. In the Ti(2)Sb structure, the corresponding Ti net is deformed to squares and rhombs in order to enhance Ti-Ti bonding, as proven by single-crystal X-ray investigation in combination with the real-space pair distribution function technique utilizing both X-ray and neutron powder diffraction data. Electronic structure calculations revealed a lowering of the total energy caused by the disorder, the major driving force being strengthened Ti-Ti interactions along the diagonal of the Ti(4) rhombs. 相似文献
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