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排序方式: 共有1075条查询结果,搜索用时 15 毫秒
41.
Nina Kunov Henrieta Havalov Gabriela Ondrovi
ov Barbora Stojkovi
ov Jacob A. Bauer Vladena Bauerov-Hlinkov Vladimir Pevala Eva Kutejov 《International journal of molecular sciences》2022,23(3)
Mitochondrial proteins are encoded by both nuclear and mitochondrial DNA. While some of the essential subunits of the oxidative phosphorylation (OXPHOS) complexes responsible for cellular ATP production are synthesized directly in the mitochondria, most mitochondrial proteins are first translated in the cytosol and then imported into the organelle using a sophisticated transport system. These proteins are directed mainly by targeting presequences at their N-termini. These presequences need to be cleaved to allow the proper folding and assembly of the pre-proteins into functional protein complexes. In the mitochondria, the presequences are removed by several processing peptidases, including the mitochondrial processing peptidase (MPP), the inner membrane processing peptidase (IMP), the inter-membrane processing peptidase (MIP), and the mitochondrial rhomboid protease (Pcp1/PARL). Their proper functioning is essential for mitochondrial homeostasis as the disruption of any of them is lethal in yeast and severely impacts the lifespan and survival in humans. In this review, we focus on characterizing the structure, function, and substrate specificities of mitochondrial processing peptidases, as well as the connection of their malfunctions to severe human diseases. 相似文献
42.
Kseniya Khamina Andreas B. Diendorfer Susanna Skalicky Moritz Weigl Marianne Pultar Teresa L. Krammer Catharine Aquino Fournier Amy L. Schofield Carolin Otto Aaron Thomas Smith Nina Buchtele Christian Schoergenhofer Bernd Jilma Bernhard J. H. Frank Jochen G. Hofstaetter Regina Grillari Johannes Grillari Klemens Ruprecht Christopher E. Goldring Hubert Rehrauer Warren E. Glaab Matthias Hackl 《International journal of molecular sciences》2022,23(3)
43.
Nadezhda S. Tian Tamara K. Meleshko Galina A. Polotskaya Iosif V. Gofman Anna V. Kashina Nina V. Kukarkina Elena N. Vlasova Zoolsho F. Zoolshoev Alexander V. Yakimansky 《Polymer Engineering and Science》2020,60(3):481-490
Composite films based on polyamide (poly(m-phenylene-iso-phthalamide)) (PA) and a brush-like polymer with polyimide (PI) backbone and side poly(methyl methacrylate) chains (PI-PMMA) were prepared by mixing individual solutions of PA and PI-PMMA and subsequent film casting. Macromolecular brushes with the same backbone length and density of side chains but with various lengths of side PMMA chains were synthesized via activator generated by electron transfer atom transfer radical polymerization. Interactions between PA and PI-PMMA, as well as distribution of PI-PMMA filler inside the PA matrix, were studied by viscometry, dynamic light scattering, differential scanning calorimetry, scanning electron microscopy, and IR spectroscopy. The mechanical properties of polymer samples were also investigated. Microphase separation was revealed in PA/PI-PMMA films. The length of side chains influences interactions between PA and PI-PMMA. At the same time, the degree of reduction in the rigidity parameters and in the elasticity parameter depends on the side chain length. Diffusion membranes were prepared on the basis of compositions with the best mechanical properties; these membranes proved to be highly efficient in pervaporation of methanol–hexane mixture. It was established that the fluxes and separation factors of the studied membranes are several times higher as compared to the corresponding characteristics of known commercial membranes. POLYM. ENG. SCI., 60:481–490, 2020. © 2019 Society of Plastics Engineers 相似文献
44.
Björn Schulz Tobias Meinert David Bierbüsse Michel Busen Nina Körtzinger Michael Stankowski Gunnar Seide 《化学,工程师,技术》2016,88(10):1501-1507
Aerogels are high‐performance materials used for space and aviation purposes. Cellulose aerogel fibers have been investigated under real space conditions for their insulation properties. The experiments were carried out in a one‐stage high‐altitude research rocket of the improved ORION type. A cuboid module with measurement cells, camera modules, and electronic devices has been developed for monitoring the insulation behavior of cellulose aerogel non‐woven samples. The thermal behavior of these samples has been analyzed and compared to cellulose cloth (cotton) and aluminum for reference. 相似文献
45.
46.
Nina Hammer Ingvar Kvande Wouter van Beek De Chen Magnus Rønning 《Topics in Catalysis》2007,45(1-4):25-29
In situ X-ray absorption spectroscopy (XAS) has been performed to investigate the active site on Au-based catalysts in the water-gas
shift (WGS) reaction. The surface area and hence the WGS activity is higher for AuTiO2 catalysts supported on carbon nanofibres (CNF) than TiO2. The WGS reaction rate depends on the Au coordination number with an apparent maximum close to eight which corresponds to
a particle size of approximately 2.5–3.0 nm. A likely cause for the changes in the electronic structure of Au is the adsorption
of CO on the surface, which also creates a small positive charge in the Au atoms. The catalytic activity significantly improves
when titania is present compared to Au deposited directly on CNF. 相似文献
47.
渤海湾盆地渤南洼陷古近系沙河街组二段沉积相特征及演化 总被引:2,自引:0,他引:2
为了查明渤海湾盆地渤南洼陷沙河街组二段沉积相分布与演化规律,为油气勘探寻找接替区,在岩心、测井、录井及地震综合研究的基础上,对沙河街组二段进行了砂层组划分与对比,进而圈定了各个时期沉积相的展布范围并总结了沉积演化规律。研究结果表明:渤南洼陷沙二段可划分为4个砂层组,各砂组依次向南逐层超覆,沉积范围不断扩大。洼陷周缘凸起带附近主要发育扇三角洲前缘沉积,以水下分流河道微相为主;其次为河口砂坝与水下分流间湾。洼陷内部以滨浅湖滩坝为主,按其成因可分为正常砂质滩坝、砂岩-碳酸盐岩混积型滩坝以及风暴成因滩坝三类,不同类型砂坝分布规律各不相同。沙二段整体呈湖盆不断扩张、沉积范围不断扩大、扇三角洲分布减少而滩坝沉积规模不断扩大的沉积演化特征。 相似文献
48.
Robert Dittmer Wook Jo Jürgen Rödel Sergei Kalinin Nina Balke 《Advanced functional materials》2012,22(20):4208-4215
Piezoresponse force microscopy (PFM) is used to afford insight into the nanoscale electromechanical behavior of lead‐free piezoceramics. Materials based on Bi1/2Na1/2TiO3 exhibit high strains mediated by a field‐induced phase transition. Using the band excitation technique the initial domain morphology, the poling behavior, the switching behavior, and the time‐dependent phase stability in the pseudo‐ternary system (1–x)(0.94Bi1/2Na1/2TiO3‐0.06BaTiO3)‐xK0.5Na0.5NbO3 (0 <= x <= 18 mol%) are revealed. In the base material (x = 0 mol%), macroscopic domains and ferroelectric switching can be induced from the initial relaxor state with sufficiently high electric field, yielding large macroscopic remanent strain and polarization. The addition of KNN increases the threshold field required to induce long range order and decreases the stability thereof. For x = 3 mol% the field‐induced domains relax completely, which is also reflected in zero macroscopic remanence. Eventually, no long range order can be induced for x >= 3 mol%. This PFM study provides a novel perspective on the interplay between macroscopic and nanoscopic material properties in bulk lead‐free piezoceramics. 相似文献
49.
Pingfan Chen Zhen Huang Changjian Li Bangmin Zhang Nina Bao Ping Yang Xiaojiang Yu Shengwei Zeng Chunhua Tang Xiaohan Wu Jingsheng Chen Jun Ding Stephen John Pennycook A. Ariando Thirumalai Venky Venkatesan Gan Moog Chow 《Advanced functional materials》2018,28(33)
The complex interfacial correlations provide new routes toward tunable functionalities. Here, the wide range of tunabilities for magnetic properties are presented, including Curie temperature (from 245 to 320 K), coercive field (from 2 to 205 Oe), and saturated magnetic moment (from 0.9 to 2.8 µB Mn?1), in a 9‐unit‐cell La2/3Sr1/3MnO3 (LSMO) layer via modifying interfacial boundary conditions. Moreover, the LSMO/PbTiO3‐based multilayers and superlattices that consist of PbTiO3/LSMO/NdGaO3 and PbTiO3/LSMO/PbTiO3 interfaces are characterized by two distinct Curie temperatures and coercive fields. The results reveal the feasibility of the interface‐resolved strategy based on boundary modification in fabricating potential devices with multiple accessible states for information storage. The wide‐range modulations on magnetic properties at LSMO/titanate interfaces are explained in terms of binary controls arising from the oxygen octahedral coupling (OOC) and magnetoelectric coupling (MEC). The results not only shed some light on understanding interfacial correlations in oxide heterostructures, but also pave an alternative path for exploring multiple accessible states in all‐oxide‐based electronic devices. 相似文献
50.
Nina Radić Bratislav M. Obradović Mirjana Kostić Biljana Dojčinović Milorad M. Kuraica Mirko Černák 《Surface & coatings technology》2012
The aim of this work is plasma activation of nonwoven polypropylene (PP) using two different ambient air plasma sources: volume dielectric barrier discharge (DBD) and diffuse coplanar surface barrier discharge (DCSBD) and its functionalization by silver ion deposition. 相似文献