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排序方式: 共有1249条查询结果,搜索用时 125 毫秒
991.
Natalia Voskoboynikova Philipp Orekhov Marine Bozdaganyan Felix Kodde Malte Rademacher Maurice Schowe Annette Budke-Gieseking Britta Brickwedde Olympia-Ekaterini Psathaki Armen Y. Mulkidjanian Katia Cosentino Konstantin V. Shaitan Heinz-Jürgen Steinhoff 《International journal of molecular sciences》2021,22(5)
Amphiphilic diisobutylene/maleic acid (DIBMA) copolymers extract lipid-encased membrane proteins from lipid bilayers in a detergent-free manner, yielding nanosized, discoidal DIBMA lipid particles (DIBMALPs). Depending on the DIBMA/lipid ratio, the size of DIBMALPs can be broadly varied which makes them suitable for the incorporation of proteins of different sizes. Here, we examine the influence of the DIBMALP sizes and the presence of protein on the dynamics of encased lipids. As shown by a set of biophysical methods, the stability of DIBMALPs remains unaffected at different DIBMA/lipid ratios. Coarse-grained molecular dynamics simulations confirm the formation of viable DIBMALPs with an overall size of up to 35 nm. Electron paramagnetic resonance spectroscopy of nitroxides located at the 5th, 12th or 16th carbon atom positions in phosphatidylcholine-based spin labels reveals that the dynamics of enclosed lipids are not altered by the DIBMALP size. The presence of the membrane protein sensory rhodopsin II from Natronomonas pharaonis (NpSRII) results in a slight increase in the lipid dynamics compared to empty DIBMALPs. The light-induced photocycle shows full functionality of DIBMALPs-embedded NpSRII and a significant effect of the protein-to-lipid ratio during preparation on the NpSRII dynamics. This study indicates a possible expansion of the applicability of the DIBMALP technology on studies of membrane protein–protein interaction and oligomerization in a constraining environment. 相似文献
992.
Joanna Giebutowicz Natalia Korytowska Monika Sobiech Sebastian Polak Barbara Winiowska Roman Piotrowski Piotr Kuakowski Piotr Luliski 《International journal of molecular sciences》2021,22(7)
The aim of this study was to develop magnetic molecularly imprinted nano-conjugate sorbent for effective dispersive solid phase extraction of antazoline (ANT) and its metabolite, hydroxyantazoline (ANT-OH) in analytical method employing liquid chromatography coupled with mass spectrometry method. The core–shell material was characterized in terms of adsorption properties, morphology and structure. The heterogeneous population of adsorption sites towards ANT-OH was characterized by two Kd and two Bmax values: Kd (1) = 0.319 µg L−1 and Bmax (1) = 0.240 μg g−1, and Kd (2) = 34.6 µg L−1 and Bmax (2) = 5.82 μg g−1. The elemental composition of magnetic sorbent was as follows: 17.55, 37.33, 9.14, 34.94 wt% for Si, C, Fe and O, respectively. The extraction protocol was optimized, and the obtained results were explained using theoretical analysis. Finally, the analytical method was validated prior to application to pharmacokinetic study in which the ANT was administrated intravenously to three healthy volunteers. The results prove that the novel sorbent could be useful in extraction of ANT and ANT-OH from human plasma and that the analytical strategy could be a versatile tool to explain a potential and pharmacological activity of ANT and ANT-OH. 相似文献
993.
Santos Adrian Vegas Sira Uyaguari Fernando Dieste Oscar Turhan Burak Juristo Natalia 《Software Quality Journal》2020,28(2):371-395
Software Quality Journal - Software engineering (SE) experiments suffer from threats to validity that may impact their results. Replication allows researchers building on top of previous... 相似文献
994.
Lebedeva Natalia Sh. Guseinov Sabir S. Yurina Elena S. Gubarev Yury A. V’yugin Anatoly I. 《Journal of Inorganic and Organometallic Polymers and Materials》2021,31(10):3991-4000
Journal of Inorganic and Organometallic Polymers and Materials - The pyrolysis of chitosan and its polymeric complexes with metal phthalocyanines was studied by thermochemical and spectral methods.... 相似文献
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Marta Ávila Natalia Gómez-Torres Pilar Gaya Sonia Garde 《International Journal of Food Science & Technology》2020,55(10):3343-3349
Clostridium tyrobutyricum causes swelling, cracks and off-flavours of cheeses (late blowing defect, LBD) due to butyric acid fermentation. To control this spoilage bacterium, we investigated the use of nisinogenic Lactococcus lactis subsp. lactis INIA 415 as starter in cheeses contaminated with C. tyrobutyricum spores. Control cheese made with spores showed LBD after 14 days of ripening. However, in cheese made with the bacteriocin producer and spores, in which (unlike control cheese) bacteriocin activity was detected throughout ripening, LBD occurred after 21 days. At this stage, level of lactic acid was 1.22-fold higher (P < 0.01) and concentrations of propionic and butyric acids were 2.15- and 2.32-fold, respectively, lower (P < 0.01) in cheese made with the nisin producer than in control cheese, according to the less pronounced spoilage symptoms showed by the former cheese. The bacteriocin producer delayed the appearance of LBD, although it cannot arrest completely C. tyrobutyricum growth. 相似文献
999.
Upasna A Agarwal Vijaya Dixit Natalia Nikolova Karuna Jain Shankar Sankaran 《International Journal of Project Management》2021,39(3):249-258
The primary purpose of this study is to examine the relationship between two leadership styles (vertical and distributed), conceptualized through types of decisions made (strategic and operational/tactical), and the state of psychological contract (fulfillment/breach) at three different levels of the organizational hierarchy in project-based organizations. The explorative analysis of eight organizations from India and Australia demonstrates the prevalence of distributed leadership: operational and technical decisions are usually entrusted to the project team and project managers, while strategic decisions are made by senior management. The study suggests that three factors facilitate a specific leadership style (vertical or distributed): organizational culture, knowledge sharing and project management practices, which in turn impact the state of psychological contract (fulfillment/breach). A flexible, collaborative organizational culture supports knowledge sharing and the adoption of agile methods, enabling distributed leadership and leading to psychological contract fulfillment. 相似文献
1000.
Alexander Vozniakovskii Sergey Kidalov Aleksei Vozniakovskii Anatoly Karmanov Ludmila Kocheva Natalia Rachkova 《Fullerenes, Nanotubes and Carbon Nanostructures》2020,28(3):238-241
AbstractThe technogenic human activities associated with the operation of nuclear power facilities lead to the contamination of natural water bodies and soils with radioactive substances, including heavy radionuclides, such as uranium and thorium. Purification of natural water bodies is a pressing environmental issue. A study of the adsorption capacity for heavy U238 and Th232 radionuclides by the samples of new carbon nanomaterials was conducted. Nanocarbon materials was synthesized based on vegetal polymers, such as technical lignin, starch and from lignocellulosic material—the bark. It was established that the investigated samples have different sorption indices in relation to radionuclides, which is determined by their chemical composition, as well as by the surface-capillary properties of carbonized materials. It is shown that the content of mobile and fixed forms of radionuclides on the investigated sorbents are significantly different. High sorption capacity of the carbonated lignin sample with respect to uranium are shown. A sample of nanocarbon materials synthesized based on the lignocellulosic complex of the bark exhibits high sorption properties in relation to thorium. The possibility of using the carbonic nanomaterial as the sorbents of radionuclides is shown. 相似文献