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861.
Farhad Hüsseinov 《International Journal of Game Theory》2008,37(3):387-395
We consider the exchange of a heterogeneous divisible commodity modeled as a measurable space. Under rational, continuous and convex preferences over characteristic measures a weak core is shown to exist. Further, a core exists if characteristic measures are mutually absolutely continuous. Applied to the land trading economy, the core existence results in Berliant (J Math Econ 14:53–56, 1985) and Dunz (Reg Sci Urban Econ 21:73–88, 1991) are obtained. 相似文献
862.
紧开覆盖的一个新的Ky Fan型匹配定理及其应用 总被引:1,自引:0,他引:1
建立了紧开覆盖的一个新的Ky Fan型匹配定理.作为应用,研究了Fan-Browder型重合定理、Ky Fan型最佳逼近定理、极大元定理及超凸空间中的定性对策和抽象经济的平衡存在定理. 相似文献
863.
一国未观测经济的规模大小,直接影响着政府统计的质量,其规模的衡量指标之一就是隐性就业规模.传统的CD函数模型估测隐性就业规模,一般采用回归分析法去估测参数.但是,回归分析法亦有其自身的缺陷.相比于传统方法,灰色理论是一种比较新颖的动态测算方法,它可以较准确地测算各个不同时期的CD函数待估系数.本文应用灰色理论的方法测算我国1982—2003年间的隐性就业规模,并基于测算结果进行了分析. 相似文献
864.
本文基于“正特片矢量法”,提出了一种在经济最优化意义下调整消耗系数的方法.该方法能够综合考虑产综和价格对消耗系数的影响,有着较好的普适性,在计算上简便易行、效果良好,且具有明显的经济意义. 相似文献
865.
张顺明 《高校应用数学学报(英文版)》2001,16(2):203-218
Abstract. This paper examines the existence of general equilibrium in a discrete time economywith the infinite horizon incomplete markets. There is a single good at each node in the eventtree. The existence of general equilibrium for the infinite horizon economy is proved by takinglimit of equilibria in truncated economies in which trade stops at a sequence of dates. 相似文献
866.
绿色化学与绿色化学教育 总被引:124,自引:10,他引:114
本文介绍了绿色化学的定义和内涵,绿色化学的 12条原则,“原子经济”概念,绿色化学的研究动态以及实施绿色化学教育的意义和方法。 相似文献
867.
Suiyi Tan Bin Yang Juan Liu Tianrong Xun Yonghong Liu 《Natural product research》2019,33(10):1467-1471
Marine micro-organisms have been proven to be excellent sources of bioactive compounds against HIV-1. Several natural products obtained from marine-derived Aspergillus fungi were screened for their activities to inhibit HIV-1 infection. Penicillixanthone A (PXA), a natural xanthone dimer from jellyfish-derived fungus Aspergillus fumigates, displayed potent anti-HIV-1 activity by inhibiting infection against CCR5-tropic HIV-1 SF162 and CXCR4-tropic HIV-1 NL4-3, with IC50 of 0.36 and 0.26 μM, respectively. Molecular docking study was conducted to understand the possible binding mode of PXA with the CCR5/CXCR4. The results revealed that, the marine-derived PXA, as a CCR5/CXCR4 dual-coreceptor antagonist, presents a new type of potential lead product for the development of anti-HIV therapeutics. 相似文献
868.
Ming-Hong Chen Wen-Long Zhang Li Chen Ru Lin Yang Xie Dong-Sheng Fang 《Natural product research》2019,33(20):2897-2903
Chemical investigation of a marine-derived actinomycete strain Verrucosispora sp. FIM06025 isolated from a marine sponge sample collected from the East China Sea, resulted in the discovery of two new alkaloids, (2-(hydroxymethyl)-3-(2-(hydroxymethyl)-3-methylaziridin-1-yl) (2-hydroxyphenyl) methanone (1) and 2-(1-hydroxyethyl)-3,4-dihydrobenzo [f] [1,4]oxazepin-5(2H)-one (2). The structures of compounds 1 and 2 were determined by the detailed analysis of 1D, 2D NMR and HR-TOF-MS data, along with literature data analysis. The bioefficacy investigations revealed that compound 1 exhibited a broad spectrum of antimicrobial activity with MIC (minimum inhibitory concentration) values ranging from 3.4 to 200?μg·mL?1 against H. pylori, P. aeroginosa, A. baumanniiin, E. coli and K. pneumonia, S. aureus, C. albicans and E. faecium, however, compound 2, up to 200?μg/mL, displayed no antibacterial activity against these bacteria. 相似文献
869.
Sara A. Cunha Rita de Castro Ezequiel R. Coscueta Manuela Pintado 《Molecules (Basel, Switzerland)》2021,26(17)
Mussel production generates losses and waste since their commercialisation must be aligned with target market criteria. Since mussels are rich in proteins, their meat can be explored as a source of bioactive hydrolysates. Thus, the main objective of this study was to establish the optimal production conditions through two Box–Behnken designs to produce, by enzymatic hydrolysis (using subtilisin and corolase), hydrolysates rich in proteins and with bioactive properties. The factorial design allowed for the evaluation of the effects of three factors (hydrolysis temperature, enzyme ratio, and hydrolysis time) on protein/peptides release as well as antioxidant and anti-hypertensive properties of the hydrolysates. The hydrolysates produced using the optimised conditions using the subtilisin protease showed 45.0 ± 0.38% of protein, antioxidant activity via ORAC method of 485.63 ± 60.65 µmol TE/g of hydrolysate, and an IC50 for the inhibition of ACE of 1.0 ± 0.56 mg of protein/mL. The hydrolysates produced using corolase showed 46.35 ± 1.12% of protein, antioxidant activity of 389.48 ± 0.21 µmol TE/g of hydrolysate, and an IC50 for the inhibition of ACE of 3.7 ± 0.33 mg of protein/mL. Mussel meat losses and waste can be used as a source of hydrolysates rich in peptides with relevant bioactive properties, and showing potential for use as ingredients in different industries, such as food and cosmetics, contributing to a circular economy and reducing world waste. 相似文献
870.