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971.
Dr. Jun Kim Byeong Jo Min Dr. Taehyun Kwon Dr. Taekyung Kim Ho Chang Song Prof. Hyung Chul Ham Dr. Hionsuck Baik Prof. Kwangyeol Lee Dr. Jin Young Kim 《化学:亚洲杂志》2021,16(22):3630-3635
Transition metal phosphides (TMPs) as ever-evolving electrocatalytic materials have attracted increasing attention in water splitting reactions owing to their cost-effective, highly active and stable catalytic properties. This work presents a facile synthetic route to NiCoP nanoparticles with Ru dopants which function as highly efficient electrocatalysts for oxygen evolution reaction (OER) in alkaline media. The Ru dopants induced a high content of Ni and Co vacancies in NiCoP nanoparticles, and the more defective Ru doped NiCoP phase than undoped NiCoP ones led to a greater number of catalytically active sites and improved electrical conductivity after undergoing electrochemical activation. The Ru doped NiCoP catalyst exhibited high OER catalytic performance in alkaline media with a low overpotential of 281 mV at 10 mA cm−2 and a Tafel slope of 42.7 mV dec−1. 相似文献
972.
The aim of this study was to evaluate the effects of root bark of Eleutherococcus sessiliflorus (ES) on osteoclast differentiation and function in vitro and in vivo. In vitro, we found that ES significantly inhibited the RANKL-induced formation of TRAP-positive multinucleated osteoclasts and osteoclastic bone resorption without cytotoxic effects. ES markedly downregulated the expression of nuclear factor of activated T cells cytoplasmic 1 (NFATc1); c-Fos; and osteoclast-related marker genes, such as TRAP, osteoclast-associated receptor (OSCAR), matrix metalloproteinase-9 (MMP-9), calcitonin receptor, cathepsin K, the 38 kDa d2 subunit of the vacuolar H+-transporting lysosomal ATPase (Atp6v0d2), dendritic cell-specific transmembrane protein (DC-STAMP), and osteoclast-stimulatory transmembrane protein (OC-STAMP). These effects were achieved by inhibiting the RANKL-mediated activation of MAPK signaling pathway proteins, including p38, ERK, and JNK. In vivo, ES attenuated OVX-induced decrease in bone volume to tissue volume ratio (BV/TV), trabecular thickness (Tb.Th), trabecular number (Tb.N), and bone mineral density, but increased trabecular separation (Tb.Sp) in the femur. Collectively, our findings showed that ES inhibited RANKL-activated osteoclast differentiation in bone marrow macrophages and prevented OVX-mediated bone loss in rats. These findings suggest that ES has the potential to be used as a therapeutic agent for bone-related diseases, such as osteoporosis. 相似文献
973.
Wonbong Lim Gayoung Jo Bo Young Lee Min Ho Park Hoon Hyun 《Particle & Particle Systems Characterization》2021,38(6):2100068
Near-infrared (NIR) fluorescence cancer imaging with targeted NIR fluorophores holds considerable promise for accurate detection and cancer diagnosis. Among the various NIR heptamethine cyanine dyes reported previously, IR783 as a single small molecule has been widely used for tumor-targeted imaging without the additional conjugation of targeting moieties. Despite the potential advantages of IR783, the major problems, such as its non-specific uptake in normal tissues/organs and slow clearance, remain to be solved. A key determinant of sensitivity and detectability in tumor imaging is the improvement of the tumor-to-background ratio (TBR). Herein, a simple and effective supramolecular complex self-assembled from IR783 and methyl-β-cyclodextrin is developed to improve tumor imaging accompanied by rapid clearance from the body. The IR783-cyclodextrin complex allowed for rapid whole body biodistribution, which remarkably reduced non-specific background uptake, and thus increased the TBR value within 24 h post-injection. Therefore, this strategy is applicable in combination with many different types of carbocyanine dyes for improved tumor imaging. 相似文献
974.
Jesica de Armas Angel A. Juan Joan M. Marquès João Pedro Pedroso 《The Journal of the Operational Research Society》2017,68(10):1161-1176
The uncapacitated facility location problem (UFLP) is a popular combinatorial optimization problem with practical applications in different areas, from logistics to telecommunication networks. While most of the existing work in the literature focuses on minimizing total cost for the deterministic version of the problem, some degree of uncertainty (e.g., in the customers’ demands or in the service costs) should be expected in real-life applications. Accordingly, this paper proposes a simheuristic algorithm for solving the stochastic UFLP (SUFLP), where optimization goals other than the minimum expected cost can be considered. The development of this simheuristic is structured in three stages: (i) first, an extremely fast savings-based heuristic is introduced; (ii) next, the heuristic is integrated into a metaheuristic framework, and the resulting algorithm is tested against the optimal values for the UFLP; and (iii) finally, the algorithm is extended by integrating it with simulation techniques, and the resulting simheuristic is employed to solve the SUFLP. Some numerical experiments contribute to illustrate the potential uses of each of these solving methods, depending on the version of the problem (deterministic or stochastic) as well as on whether or not a real-time solution is required. 相似文献
975.
Jo GB Choi JH Christensen CA Pasquini TA Lee YR Ketterle W Pritchard DE 《Physical review letters》2007,98(18):180401
The recombination of two split Bose-Einstein condensates on an atom chip is shown to result in heating which depends on the relative phase of the two condensates. This heating reduces the number of condensate atoms between 10% and 40% and provides a robust way to read out the phase of an atom interferometer without the need for ballistic expansion. The heating may be caused by the dissipation of dark solitons created during the merging of the condensates. 相似文献
976.
Jo GB Shin Y Will S Pasquini TA Saba M Ketterle W Pritchard DE Vengalattore M Prentiss M 《Physical review letters》2007,98(3):030407
We measure the relative phase of two Bose-Einstein condensates confined in a radio frequency induced double-well potential on an atom chip. We observe phase coherence between the separated condensates for times up to approximately 200 ms after splitting, a factor of 10 longer than the phase diffusion time expected for a coherent state for our experimental conditions. The enhanced coherence time is attributed to number squeezing of the initial state by a factor of 10. In addition, we demonstrate a rotationally sensitive (Sagnac) geometry for a guided atom interferometer by propagating the split condensates. 相似文献
977.
A new antifungal piperidone derivative 3alpha,4alpha-epoxy-2-piperidone, whose structure was determined by spectroscopic methods, was isolated from the MeOH extract from leaves of Piper crassinervium. This is the first occurrence of one amide in P. crassinervium. 相似文献
978.
979.
A novel series of compounds, derived from 2,5-functionalized imidazoles, have been synthesized as potential bisubstrate inhibitors of protein farnesyltransferase (FTase) using structure-based design. These compounds have a 1,4-diacid chain and a tripeptide connected by an imidazole ring. The synthetic strategy relies on the functionalization at the C-2 position of the heterocycle with the diacid side chain and peptide coupling at the C-5 position. Several new compounds were synthesized in good yields. Kinetic experiments on the most active compounds revealed different binding modes depending on the diacid chain length. 相似文献
980.
Sandra K Verleysen K Labeur C Vanneste L D'Hondt F Thomas G Kas K Gevaert K Vandekerckhove J Sandra P 《Journal of separation science》2007,30(5):658-668
The previously reported COmbined FRActional DIagonal Chromatography (COFRA-DIC) methodology, in which a subset of peptides representative for their parent proteins are sorted, is particularly powerful for whole proteome analysis. This peptide-centric technology is built around diagonal chromatography, where peptide separations are crucial. This paper presents high efficiency peptide separations, in which four 250 x 2.1 mm, 5 microm Zorbax 300SB-C18 columns (total length 1 m) were coupled at operating temperatures of 60'C using a dedicated LC oven and conventional LC equipment. The high efficiency separations were combined with the COFRADIC procedure. This extremely powerful combination resulted, for the analysis of serum, in an increase in the uniquely identified peptide sequences by a factor of 2.6, compared to the COFRADIC procedure on a 25 cm column. This is a reflection of the increased peak capacity obtained on the 1 m column, which was calculated to be a factor 2.7 higher than on the 25 cm column. Besides more efficient sorting, less ion suppression was noticed. 相似文献