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排序方式: 共有238条查询结果,搜索用时 31 毫秒
1.
SeyedHosein Payandeh Daniel Rentsch Zbigniew Łodziana Ryo Asakura Laurent Bigler Radovan Černý Corsin Battaglia Arndt Remhof 《Advanced functional materials》2021,31(18):2010046
Hydroborate-based solid electrolytes have recently been successfully employed in high voltage, room temperature all-solid-state sodium batteries. The transfer to analogous lithium systems has failed up to now due to the lower conductivity of the corresponding lithium compounds and their high cost. Here LiB11H14 nido-hydroborate as a cost-effective building block and its high-purity synthesis is introduced. The crystal structures of anhydrous LiB11H14 as well as of LiB11H14-based mixed-anion solid electrolytes are solved and high ionic conductivities of 1.1 × 10−4 S cm−1 for Li2(B11H14)(CB11H12) and 1.1 × 10−3 S cm−1 for Li3(B11H14)(CB9H10)2 are obtained, respectively. LiB11H14 exhibits an oxidative stability limit of 2.6 V versus Li+/Li and the proposed decomposition products are discussed based on density functional theory calculations. Strategies are discussed to improve the stability of these compounds by modifying the chemical structure of the nido-hydroborate cage. Galvanostatic cycling in symmetric cells with two lithium metal electrodes shows a small overpotential increase from 22.5 to 30 mV after 620 h (up to 0.5 mAh cm−2), demonstrating that the electrolyte is compatible with metallic anodes. Finally, the Li2(B11H14)(CB11H12) electrolyte is employed in a proof-of-concept half cell with a TiS2 cathode with a capacity retention of 82% after 150 cycles at C/5. 相似文献
2.
Agata Campisi Giuseppina Raciti Giovanni Sposito Rosaria Grasso Maria A. Chiacchio Michela Spatuzza Alessandro Attanzio Ugo Chiacchio Luisa Tesoriere Mario Allegra Rosalia Pellitteri 《International journal of molecular sciences》2021,22(7)
Herein, we assessed the effect of full native peptide of amyloid-beta (Aβ) (1-42) and its fragments (25-35 and 35-25) on tissue transglutaminase (TG2) and its isoforms (TG2-Long and TG2-Short) expression levels on olfactory ensheathing cells (OECs). Vimentin and glial fibrillary acid protein (GFAP) were also studied. The effect of the pre-treatment with indicaxanthin from Opuntia ficus-indica fruit on TG2 expression levels and its isoforms, cell viability, total reactive oxygen species (ROS), superoxide anion (O2−), and apoptotic pathway activation was assessed. The levels of Nestin and cyclin D1 were also evaluated. Our findings highlight that OECs exposure to Aβ(1-42) and its fragments induced an increase in TG2 expression levels and a different expression pattern of its isoforms. Indicaxanthin pre-treatment reduced TG2 overexpression, modulating the expression of TG2 isoforms. It reduced total ROS and O2− production, GFAP and Vimentin levels, inhibiting apoptotic pathway activation. It also induced an increase in the Nestin and cyclin D1 expression levels. Our data demonstrated that indicaxanthin pre-treatment stimulated OECs self-renewal through the reparative activity played by TG2. They also suggest that Aβ might modify TG2 conformation in OECs and that indicaxanthin pre-treatment might modulate TG2 conformation, stimulating neural regeneration in Alzheimer’s disease. 相似文献
3.
Pedrini Matteo Langella Valentina Battaglia Mario Alberto Zaratin Paola 《Scientometrics》2018,114(3):1227-1250
Scientometrics - In recent year, a growing attention is dedicated to the assessment of research’s social impact. While prior research has often dealt with results of research, the last decade... 相似文献
4.
Ching-Yee Loo Paul M. Young Rosalia Cavaliere Cynthia B. Whitchurch Wing-Hin Lee 《Drug development and industrial pharmacy》2014,40(6):719-729
Objectives: Silver nanoparticles (AgNPs) with a size ranging from 7 to 70?nm were synthesized using the ascorbic acid-citrate seed-mediated growth approach at room temperature.Methods: The 8?nm silver particles were prepared using gallic acid in alkaline conditions and used as seed to prepare AgNPs.Results: The presence of ascorbic acid and citrate allows the regulation of size and size distribution of the nanoparticles. The increase in free silver ion-to-seed ratio (Ag+/Ag0) resulted in changes of particle shape from spherical to pseudo-spherical and minor cylindrical shape. Further, a repetitive seeding approach resulted in the formation of pseudo-spherical particles with higher polydispersity index and minor distributions of tetrahedral particles. Citrate-capped AgNPs were stable and did not agglomerate upon centrifugation. The effect of AgNPs on biofilm reduction was evaluated using static culture on 96-well microtiter plates. Results showed that AgNPs with the smallest average diameter were most effective in the reduction of Pseudomonas aeruginosa biofilm colonies, which accounted for 90% of removal.Conclusion: The biofilm removal activities of the nanoparticles were found to be concentration-independent particularly for the concentration within the range of 80–200?µg/mL. 相似文献
5.
6.
A. J. Redd D. J. Battaglia M. W. Bongard R. J. Fonck E. T. Hinson B. A. Kujak-Ford B. T. Lewicki A. C. Sontag G. R. Winz 《Journal of Fusion Energy》2009,28(2):203-207
Recent Pegasus experiments are developing solenoid-free startup techniques using point-source magnetic helicity injection.
These plasma sources, called “plasma guns”, ionize a stream of gas in a discharge channel, and bias this channel with respect
to an external electrode, driving current along the plasma stream, which relaxes into a tokamak-like equilibrium. The relaxed
discharges formed by these injectors exhibit high current amplification, which is the ratio of total toroidal current to the
gun-driven current. The development and present design of these injectors are described, and time traces from a typical discharge
are presented. 相似文献
7.
D. J. Battaglia M. W. Bongard R. J. Fonck A. J. Redd A. C. Sontag 《Journal of Fusion Energy》2009,28(2):140-143
Solenoid-free tokamak startup via point-source DC helicity injection is demonstrated on the Pegasus Toroidal Experiment using
a high current density, low impurity plasma gun mounted near the outboard midplane. A threshold in the vacuum vertical magnetic
field strength that allows the injected current filament to relax into a tokamak-like topology is observed. A simple 2-D model
of the vacuum magnetic field suggests this threshold is the maximum field strength that allows a toroidally connected field
null to form. Discharges with I
p ≈ 17 kA are produced using less than 2 kA of injected current and no inductive drive. The tokamak-like discharges exhibit
current decay times about five times longer than the injected current decay, expansion of the plasma into the vacuum region
and a significant increase in the line-integrated density. 相似文献
8.
Adam R. Brown Rosalia C. M. Simmen Frank A. Simmen 《International journal of molecular sciences》2013,14(8):16240-16257
Thyroid hormones play a critical role in the growth and development of the alimentary tract in vertebrates. Their effects are mediated by nuclear receptors as well as the cell surface receptor integrin αVβ3. Systemic thyroid hormone levels are controlled via activation and deactivation by iodothyronine deiodinases in the liver and other tissues. Given that thyroid hormone signaling has been characterized as a major effector of digestive system growth and homeostasis, numerous investigations have examined its role in the occurrence and progression of cancers in various tissues of this organ system. The present review summarizes current findings regarding the effects of thyroid hormone signaling on cancers of the esophagus, stomach, liver, pancreas, and colon. Particular attention is given to the roles of different thyroid hormone receptor isoforms, the novel integrin αVβ3 receptor, and thyroid hormone-related nutrients as possible protective agents and therapeutic targets. Future investigations geared towards a better understanding of thyroid hormone signaling in digestive system cancers may provide preventive or therapeutic strategies to diminish risk, improve outcome and avert recurrence in afflicted individuals. 相似文献
9.
10.
Rodriguez-Rodriguez R Justo ML Claro CM Vila E Parrado J Herrera MD Alvarez de Sotomayor M 《Food chemistry》2012,135(3):1044-1051
The aim of the present study was to evaluate the vascular effects of an enzymatic extract of grape pomace (GP-EE) on isolated arteries, focusing our attention on endothelium-derived relaxation and on its antioxidant properties. Grape pomace derived from wine making was extracted by an enzymatic process and its composition of polyphenols was evaluated by HPLC and ESI-MS/MS, detecting kaempferol, catechin, quercetin and procyanidins B1 and B2, trace levels of resveratrol and tracing out gallocatechin and anthocyanidins. GP-EE induced endothelium- and NO-dependent vasodilatation of both rat aorta and small mesenteric artery (SMA) segments and reduced Phe-induced response in aortic rings. Both ORAC and DPPH assays confirmed antioxidant scavenging properties of GP-EE, which also prevented O(2)(·-) production (assessed by DHE fluorescence) and contraction elicited by ET-1. These results provide evidence that GP-EE possesses interesting antioxidant and protective vascular properties and highlight the potential interest of this extract as a functional food. 相似文献