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941.
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943.
944.
Vera N. Smolyaninova Jonathon Cartelli Nathaniel Christopher Benjamin Kist Jonathan Perry Stephanie Spickard Mary Sajini Devadas Igor I. Smolyaninov 《Annalen der Physik》2024,536(3):2300408
Recent theoretical and experimental work demonstrated that nonlinear optics of ferrofluid-based hyperbolic metamaterials exhibit very unusual spatiotemporal dynamics. Here a detailed theoretical and experimental study of mutual interactions of individual self-focused optical filaments inside this metamaterial is reported. In agreement with theoretical expectations, the observed mutual interactions of individual filaments exhibit strong similarities with general relativity in 2+1 dimensions, which predicts that these interactions must have predominantly non-Newtonian topological character. This observation is important since 2+1-dimensional gravity is an exactly solvable theory even in the quantum gravity limit. 相似文献
945.
We demonstrate that high-quality large-scale ZnO inverse opals can be fabricated by a simple sol–gel technique, comprising infiltration of polystyrene colloidal crystal films with zinc nitrate solution, drying and annealing at 300 C. This simple method yields continuous films, which consist of inverse opal domains (up to several hundreds of μm2 in size), separated by small cracks filled with zinc oxide. Microradian X-ray diffraction was employed to verify the crystalline quality of ZnO inverse opals on the macroscale, revealing that the samples have a predominant face-centered cubic structure, and that the majority of domains have the same crystallographic orientation. The samples exhibit bright iridescence and possess photonic stop-bands in the visible to near-infrared spectrum. 相似文献
946.
947.
Sylwia Cyboran-Mikoajczyk Katarzyna Mczarska Katarzyna Solarska-
ciuk Katarzyna Ratajczak-Wielgomas Jan Oszmiaski Vera Jencova Dorota Bonarska-Kujawa 《Molecules (Basel, Switzerland)》2022,27(18)
The aim of this work is to determine the biological activity of ellagitannins rich extracts from leaves of raspberry (Rubus idaeus L.) and wild strawberry (Fragaria vesca L.) in relation to cells and cell membranes. Detailed qualitative and quantitative analysis of phenolic compounds of the extract was made using chromatographic methods. Cytotoxic and antioxidant activities of tested extracts in relation to erythrocytes and human vascular endothelial cells (HMEC-1) were determined by using fluorimetric and spectrophotometric methods. In order to establish the influence of the extracts on the physical properties of the membrane, such as osmotic resistance and erythrocytes shapes, mobility and/or hydration of polar heads and fluidity of hydrocarbon chains of membrane lipids, microscopic and spectroscopic methods were used. The results showed that the extracts are non-toxic for erythrocytes and HMEC-1 cells (up to concentration of 50 µg/mL), but they effectively protect cells and their membranes against oxidative damage. The increase in osmotic resistance of erythrocytes, formation of echinocytes and changes only in the polar part of the membrane caused by the extracts demonstrate their location mainly in the hydrophilic part of the membrane. The results indicate that tested extracts have high biological activities and may be potentially used in delaying the ageing process of organisms and prevention of many diseases, especially those associated with oxidative stress. 相似文献
948.
Ksenia A. Sapozhnikova Evgeny L. Gulyak Vsevolod A. Misyurin Maria A. Simonova Ekaterina V. Ryabukhina Anastasiya V. Alexeeva Nataliya A. Tikhonova Natalia A. Lyzhko Galina P. Popova Andrey V. Misyurin Alexey V. Ustinov Vladimir A. Korshun Vera A. Alferova Dmitry Yu. Ryazantsev Vladimir A. Brylev 《Molecules (Basel, Switzerland)》2023,28(1)
Fluorescent antibodies have proved to be an invaluable tool for molecular biology and diagnostics. They are routinely produced by modification of lysine residues, which leads to high heterogeneity. As such, their affinity may be compromised if the antigen-binding site is affected, the probability of which increases along with the degree of labeling. In this work, we propose a methodology for the synthesis of site-specific antibody-dye conjugates with a high degree of labeling. To this end, we synthesized two oxyamine-based branched triazide linkers and coupled them with a periodate-oxidized anti-PRAME antibody 6H8; two oxyamine-based linear monoazide linkers of similar structure were used as controls. The azide-labeled antibodies were subsequently conjugated with fluorescent dyes via SPAAC, a copper-free click reaction. Compared to their counterparts made with linear linkers, the branched conjugates possessed a higher degree of labeling. The utility of the methodology was demonstrated in the detection of the PRAME protein on the surface of the cell by flow cytometry. 相似文献
949.
An electrochemically induced synthesis of imidazoles from vinyl azides and benzyl amines was developed. A wide range of imidazoles were obtained, with yields of 30 to 64%. The discovered transformation is a multistep process whose main steps include the generation of electrophilic iodine species, 2H-azirine formation from the vinyl azide, followed by its reactions with benzyl amine and with imine generated from benzyl amine. The cyclization and aromatization of the obtained intermediate lead to the target imidazole. The synthesis proceeds under constant current conditions in an undivided cell. Despite possible cathodic reduction of various unsaturated intermediates with C=N bonds, the efficient electrochemically induced synthesis of imidazoles was carried out. 相似文献
950.
Dr. Vera Tchakalova Dr. Eric Lutz Serge Lamboley Dr. Emilie Moulin Dr. Daniel Benczédi Prof. Dr. Nicolas Giuseppone Dr. Andreas Herrmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(53):13468-13476
Amphiphilic imines prepared by condensation of a hydrophobic fragrance aldehyde with a hydrophilic amine derived from a poly(propylene oxide) and poly(ethylene oxide) diblock copolymer were investigated as cleavable surfactant profragrances in applications of functional perfumery. In water, the cleavable surfactants assemble into micelles that allow solubilization of perfume molecules that are not covalently attached to the surfactant. Dynamic headspace analysis on a glass surface showed that solubilized perfume molecules evaporated in a similar manner in the presence of the cleavable surfactant as compared with a non-cleavable reference surfactant. Under application conditions, the cleavable surfactant imine hydrolysed to release the covalently linked fragrance aldehyde. The profragrances were stable during storage in aqueous media, and upon dilution showed a blooming effect for the hydrolytical fragrance release and a more balanced performance of a solubilized perfume by retaining the more volatile fragrances and boosting the evaporation of the less volatile fragrances. 相似文献