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排序方式: 共有3297条查询结果,搜索用时 171 毫秒
1.
Dr. Elena Petit Dr. Lluís Bosch Prof. Anna M. Costa Ignacio Rodríguez-Izquierdo Dr. Daniel Sepúlveda-Crespo Prof. M. Angeles Muñoz-Fernández Prof. Jaume Vilarrasa 《ChemMedChem》2021,16(14):2217-2222
Amides from indole-3-glyoxylic acid and 4-benzoyl-2-methylpiperazine, which are related to entry inhibitors developed by Bristol-Myers Squibb (BMS), have been synthesized with aliphatic chains located at the C7 position of the indole ring. These spacers contain an azido group suitable for the well-known Cu(I)-catalyzed (3+2)-cycloaddition or an activated triple bond for the nucleophilic addition of thiols under physiological conditions. Reaction with polyols (β-cyclodextrin and hyperbranched polyglycerol) decorated with complementary click partners has afforded polyol-BMS-like conjugates that are not cytotoxic (TZM.bl cells) and retain the activity against R5-HIV-1NLAD8 isolates. Thus, potential vaginal microbicides based on entry inhibitors, which can be called of 4th generation, are reported here for the first time. 相似文献
2.
Isabel Fernandes Cecília Melo-Alvim Raquel Lopes-Brs Miguel Esperana-Martins Luís Costa 《International journal of molecular sciences》2021,22(2)
Osteosarcoma (OS) is a rare condition with very poor prognosis in a metastatic setting. Basic research has enabled a better understanding of OS pathogenesis and the discovery of new potential therapeutic targets. Phase I and II clinical trials are already ongoing, with some promising results for these patients. This article reviews OS pathogenesis and new potential therapeutic targets. 相似文献
3.
YanXin Dan Takashi Costa Atsushi Nakamura Keiji Komatsu Hidetoshi Saitoh 《Ceramics International》2021,47(9):11862-11869
The morphology and microstructure of splats impact the comprehensive capability of a new coating methodology called chelate flame spraying (CFS). This study addresses the quantitative characterization of the spread morphologies of flame sprayed Er2O3 splats directly deposited under different spray conditions on aluminum alloy substrates with a mirror finish. The influence of the in-flight particle temperature and velocity, carrier gas type, and carrier gas ratio on the solidification mechanism of molten droplets was investigated. Image analysis methods were employed to identify single splats from the morphology observed with field-emission scanning electron microscopy (FE-SEM). In addition, Er2O3 films were synthesized on an Al–Mg alloy (A5052) substrate using N2 or O2 as the carrier gas. When O2 was used as the carrier gas, 109-μm-thick films were deposited on the A5052 substrate. The cross-sectional porosity of the films was 3.8%. In contrast, films with 101-μm thickness were synthesized on the A5052 substrate when N2 was used as the carrier gas. The cross-sectional porosity of these films was 13.8%. The results showed that the carrier gas type (N2) and carrier gas ratio had a significant effect on the flattening behavior of the molten droplets. A spraying method combined with multidimensional modes is proposed to control the morphology of the splats. 相似文献
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Laise Cedraz Pinto Tainá Pinheiro de Oliveira Rayane de Souza Nathane Brito Ferreira Santos Luis Fernandes Pereira Santos Andréa de Assis Santos Teodora Xavier dos Santos Carolaine Teixeira Santos Catarina de Jesus Nunes Isis Barbosa Costa Amanda Catariny de Oliveira Marly Silveira Santos Clícia Maria de Jesus Benevides Mariângela Vieira Lopes 《Journal of Food Processing and Preservation》2021,45(2):e15113
7.
Katarzyna Świrk Paulina Summa Dominik Wierzbicki Monika Motak Patrick Da Costa 《International Journal of Hydrogen Energy》2021,46(34):17776-17783
A series of V-promoted hydrotalcite-derived nickel catalysts (1.0, 2.0, and 4.0 wt%) were tested in CO2 methanation. Ni–I–V2.0 with 2.0 wt% vanadium loading showed the highest catalytic activity, achieving 74.7% of CO2 conversion and 100% of CH4 selectivity at 300 °C. XRD and XANES analyses showed that the smallest Ni0 particles in Ni–I–V2.0 were consistent with the improved textural features observed for this catalyst. Moreover, CO2-TPD revealed the highest sum of weak and medium basic sites in Ni–I–V2.0 that can positively influence catalytic behavior. For the studied catalysts, a clear correlation was demonstrated between the catalytic activity and specific surface area, as well as the basic properties. 相似文献
8.
Leonardo da Costa Andr Neto Billy Pinheiro Weverton Cordeiro Roberto Araújo Antnio Abelm 《International Journal of Network Management》2019,29(3)
In blockchain, full nodes (FNs) are peers that store and verify entire chains of transactions. In contrast, light clients (LCs) are those with limited resources, and for this reason, they request only block headers from FNs for transaction verification—using protocols like Simple Payment Verification (SPV). In an approach to prevent FN tampering on transaction verification (byzantine fault), LCs request block headers from multiple FNs and compare received responses. One problem with this approach is that an LC must connect to each FN and perform the same cryptographic operations with each one repeatedly, which leads to client‐side complexity and slower response. We propose an alternate approach to tackle this issue, in which LCs can encrypt a request for block headers only once, and send that request to a predetermined set of FNs to access, process, and reply back in a single response. Our approach, called Distributed Lightweight Client Protocol (DLCP), enables LCs to verify with little effort if FNs have agreed on a response. From an experimental evaluation, we observed that DLCP provided lower latency and reduced computing and communication overhead in comparison with the existing conventional approach. 相似文献
9.
Giulio Costa Marco Montemurro Jérôme Pailhès 《International Journal of Mechanics and Materials in Design》2018,14(4):669-696
In this paper, the solid isotropic material with penalisation (SIMP) method for topology optimisation of 2D problems is reformulated in the non-uniform rational BSpline (NURBS) framework. This choice implies several advantages, such as the definition of an implicit filter zone and the possibility for the designer to get a geometric entity at the end of the optimisation process. Therefore, important facilities are provided in CAD postprocessing phases in order to retrieve a consistent and well connected final topology. The effect of the main NURBS parameters (degrees, control points, weights and knot-vector components) on the final optimum topology is investigated. Classic geometric constraints, as the minimum and maximum member size, have been integrated and reformulated according to the NURBS formalism. Furthermore, a new constraint on the local curvature radius has been developed thanks to the NURBS formalism and properties. The effectiveness and the robustness of the proposed method are tested and proven through some benchmarks taken from literature and the results are compared with those provided by the classical SIMP approach. 相似文献
10.
Costa José Arnaldo S. Costa Vinicius C. Pereira-Filho Edenir R. Paranhos Caio M. 《SILICON》2020,12(8):1895-1903
Silicon - A previously synthesized PABA-MCM-41 mesoporous material was used to remove Cr(VI) in leather samples. The optimization step was performed using univariate method for the following... 相似文献