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951.
952.
Wen Li Yunyun Li Ying Wang Zhengyang Zhou Chao Wang Yiyang Sun Jianyong Sheng Jiawen Xiao Qian Wang Shunsuke Kurosawa Maksym Buryi David John Karin Paurová Martin Nikl Xiaoping OuYang Yuntao Wu 《Laser \u0026amp; Photonics Reviews》2024,18(2):2300860
The urgency for cost-effective, high-resolution, flexible X-ray imaging detectors is generating great demand for scintillators with low-temperature processability, high scintillation yield, and negligible afterglow. X-ray imaging materials are currently dominated by inorganic scintillators in the form of rigid films and bulk crystals, which have inherent limitations including high-temperature, complex synthesis, and considerable challenges toward advanced nonplanar imaging. Here, high-performance and flexible X-ray scintillators based on novel zero-dimensional (0D) (BTPP)2MnX4 (BTPP = benzyltriphenylphosphonium; X = Cl, Br) halides are reported. They emit bright green light originating from the 4T1-6A1 transition of Mn2+ under X-ray excitation. In particular, (BTPP)2MnBr4 single crystals exhibit excellent air- and radiation-stability, a high scintillation yield of 53 000 photons MeV−1, a low detection limit of 89.9 nGyair s−1, and an ultralow afterglow comparable to commercial Bi4Ge3O12 (BGO) single crystals. Moreover, the (BTPP)2MnCl4@polydimethylsiloxane (PDMS) flexible scintillation screens achieve a high spatial resolution of 14.1 lp mm−1 and realize high-quality imaging results of nonplanar objects. This study demonstrates that the flexible scintillation screens based on low-dimensional Mn(II) hybrid halides have significant potential for low-dose and high-resolution X-ray imaging applications. 相似文献
953.
954.
In recent years, Smolyak quadrature rules (also called quadratures on hyperbolic cross points or sparse grids) have gained interest as possible competition to number theoretic quadratures for high dimensional problems. A standard way of comparing the quality of multivariate quadrature formulas consists in computing theirL2-discrepancy. Especially for larger dimensions, such computations are a highly complex task. In this paper we develop a fast recursive algorithm for computing theL2-discrepancy (and related quality measures) of general Smolyak quadratures. We carry out numerical comparisons between the discrepancies of certain Smolyak rules and Hammersley and Monte Carlo sequences. 相似文献
955.
956.
Karin Schmitz 《Nachrichten aus der Chemie》1996,44(10):1051-1051
957.
Luis Daniel Goyzueta-Mamani Haruna Luz Barazorda-Ccahuana Miguel Angel Chvez-Fumagalli Karla Lucia F. Alvarez Jorge Alberto Aguilar-Pineda Karin Jannet Vera-Lopez Christian Lacks Lino Cardenas 《Molecules (Basel, Switzerland)》2022,27(3)
Background: Despite research on the molecular bases of Alzheimer’s disease (AD), effective therapies against its progression are still needed. Recent studies have shown direct links between AD progression and neurovascular dysfunction, highlighting it as a potential target for new therapeutics development. In this work, we screened and evaluated the inhibitory effect of natural compounds from native Peruvian plants against tau protein, amyloid beta, and angiotensin II type 1 receptor (AT1R) pathologic AD markers. Methods: We applied in silico analysis, such as virtual screening, molecular docking, molecular dynamics simulation (MD), and MM/GBSA estimation, to identify metabolites from Peruvian plants with inhibitory properties, and compared them to nicotinamide, telmisartan, and grapeseed extract drugs in clinical trials. Results: Our results demonstrated the increased bioactivity of three plants’ metabolites against tau protein, amyloid beta, and AT1R. The MD simulations indicated the stability of the AT1R:floribundic acid, amyloid beta:rutin, and tau:brassicasterol systems. A polypharmaceutical potential was observed for rutin due to its high affinity to AT1R, amyloid beta, and tau. The metabolite floribundic acid showed bioactivity against the AT1R and tau, and the metabolite brassicasterol showed bioactivity against the amyloid beta and tau. Conclusions: This study has identified molecules from native Peruvian plants that have the potential to bind three pathologic markers of AD. 相似文献
958.
Affinity chromatography is the most selective chromatographic method for the purification of biologically active materials. It is based on the biospecific interaction of the substrates with a ligand, which is chemically immobilized onto a suitable matrix (support). Different matrices provided by natural and synthetic polymers are used for the preparation of affinity supports. In this communication we describe and compare the properties of various supports based on polysaccharides, polyacrylamides and inorganic materials. In particular, we discuss the utility of different silica derivatives (especially primary hydroxyl silica) for the immobilization of ligands and high-performance affinity chromatography. 相似文献
959.
Dominik Jacob Kathrin Thüring Aurellia Galliot Virginie Marchand Adeline Galvanin Akif Ciftci Karin Scharmann Michael Stock Jean‐Yves Roignant Sebastian A. Leidel Yuri Motorin Raffael Schaffrath Roland Klassen Mark Helm 《Angewandte Chemie (International ed. in English)》2019,58(28):9565-9569
Accurate quantification of the copy numbers of noncoding RNA has recently emerged as an urgent problem, with impact on fields such as RNA modification research, tissue differentiation, and others. Herein, we present a hybridization‐based approach that uses microscale thermophoresis (MST) as a very fast and highly precise readout to quantify, for example, single tRNA species with a turnaround time of about one hour. We developed MST to quantify the effect of tRNA toxins and of heat stress and RNA modification on single tRNA species. A comparative analysis also revealed significant differences to RNA‐Seq‐based quantification approaches, strongly suggesting a bias due to tRNA modifications in the latter. Further applications include the quantification of rRNA as well as of polyA levels in cellular RNA. 相似文献
960.
Kristina O. Kvashnina Anna Yu. Romanchuk Ivan Pidchenko Lucia Amidani Evgeny Gerber Alexander Trigub Andre Rossberg Stephan Weiss Karin Popa Olaf Walter Roberto Caciuffo Andreas C. Scheinost Sergei M. Butorin Stepan N. Kalmykov 《Angewandte Chemie (International ed. in English)》2019,58(49):17878-17878