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21.
We present a geometric characterization of acceptance sets for monotone, co-monotone and convex risk measures on finite state spaces. Geometrically, such acceptance sets can be represented by convex polygons with edges only on certain hyperplanes. We also provide some lower dimensional examples, and study acceptance sets for value at risk and expected shortfall. 相似文献
22.
Lin Feng Wang Ze Yu Zhang Liang Zhao Yu Jie Zhou 《Mathematical Methods in the Applied Sciences》2017,40(4):992-1002
We prove that on a smooth metric measure space with m ?Bakry–Émery curvature bounded from below by ?(m ? 1)K for some constant K ≥0 (i.e., Ricf ,m ≥?(m ? 1)K ), the following degenerate elliptic equation (0.1) has no nonconstant positive solution when p > 1 and constant λ f ,p satisfies Our approach is based on the local Sobolev inequality and the Moser's iterative technique and is different from Cheng‐Yau's method, which was used by Wang‐Zhu in 2012 to derive a same Liouville theorem when 1 < p ≤2, Ricf ,m ≥?(m ? 1)K and the sectional curvature is bounded from below. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Candida Manelfi Jonas Gossen Silvia Gervasoni Carmine Talarico Simone Albani Benjamin Joseph Philipp Francesco Musiani Giulio Vistoli Giulia Rossetti Andrea Rosario Beccari Alessandro Pedretti 《Molecules (Basel, Switzerland)》2021,26(4)
The 3CL-Protease appears to be a very promising medicinal target to develop anti-SARS-CoV-2 agents. The availability of resolved structures allows structure-based computational approaches to be carried out even though the lack of known inhibitors prevents a proper validation of the performed simulations. The innovative idea of the study is to exploit known inhibitors of SARS-CoV 3CL-Pro as a training set to perform and validate multiple virtual screening campaigns. Docking simulations using four different programs (Fred, Glide, LiGen, and PLANTS) were performed investigating the role of both multiple binding modes (by binding space) and multiple isomers/states (by developing the corresponding isomeric space). The computed docking scores were used to develop consensus models, which allow an in-depth comparison of the resulting performances. On average, the reached performances revealed the different sensitivity to isomeric differences and multiple binding modes between the four docking engines. In detail, Glide and LiGen are the tools that best benefit from isomeric and binding space, respectively, while Fred is the most insensitive program. The obtained results emphasize the fruitful role of combining various docking tools to optimize the predictive performances. Taken together, the performed simulations allowed the rational development of highly performing virtual screening workflows, which could be further optimized by considering different 3CL-Pro structures and, more importantly, by including true SARS-CoV-2 3CL-Pro inhibitors (as learning set) when available. 相似文献
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The development of the anti-malaria vaccine holds a promising future in malaria control. One of the anti-malaria vaccine strategies known as the transmission-blocking vaccine (TBV) is to inhibit the parasite transmission between humans and mosquitoes by targeting the parasite gametocyte. Previously, we found that P48/45 included in the 6-Cysteine protein family shared by Plasmodium sp. We also detected vaccine properties possessed by all human-infecting Plasmodium and could be used as a cross-species anti-malaria vaccine. In this study, we investigated the efficacy of P48/45 through the ancestral and consensus reconstruction approach. P48/45 phylogenetic and time tree analysis was done by RAXML and BEAST2. GRASP server and Ugene software were used to reconstruct ancestral and consensus sequences, respectively. The protein structural prediction was made by using a psipred and Rosetta program. Each protein characteristic of P48/45 was analyzed by assessing hydrophobicity and Post-Translational Modification sites. Meanwhile, the Epitope sequence for B-cell, T-cell, and HLA was determined using an immunoinformatics approach. Lastly, molecular docking simulation was done to determine native binding interactions of P48/45-P230. The result showed a distinct protein characteristic of ancestral and consensus sequences. The immunogenicity analysis revealed the number of epitopes in the ancestral sequence is greater than the consensus sequence. The study also found a conserved epitope located in the binding site and consists of specific Post-Translational Modification sites. Hence, our research provides detailed insight into ancestral and consensus P48/45 efficacy for the cross-species anti-malaria vaccine. 相似文献
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Zhenxin Liu 《数学研究通讯:英文版》2023,39(3):476-500
The limit distribution for homogeneous Markov processes is studied extensively and well understood, but it is not the case for inhomogeneous
Markov processes. In this paper, we review some recent results on inhomogeneous Markov processes generated by non-autonomous stochastic (partial)
differential equations (SDE in short). Under some suitable conditions, we show
that the distribution of recurrent solutions of SDEs constitutes the limit distribution of the corresponding inhomogeneous Markov processes. 相似文献
30.
针对群体评价中共识集结的相关问题,从仿真的视角讨论了评价信息随机化的群体共识聚合求解方法。首先,面向实数类型的评价信息,将精确性的数据给予一定的宽松性处理,进一步结合正态分布的3σ原则,利用随机模拟的方式集结出带有概率特征的可能性排序;其次,面向区间数类型的评价信息,整合出各子区间发生概率不同的区间数评价信息,在充分随机模拟的情况下,给出了带有优胜概率特征的可能性排序。最后,通过相应的算例进行求解分析,说明了该方法的可行性和有效性。基于群体共识视角,针对实数和区间数两种类型的评价信息,分别进行相应的随机化处理,并为进一步探索区间数的分布形式提供了一种新的研究思路。 相似文献