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Iron Chloride Hexahydrate-catalyzed Friedel-Crafts Akylation of Cyclic Ketene Dithioacetals with Alcohols

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Chemical Research in Chinese Universities 2016年第3期32卷 390-395页

作者： YU Haifeng liao Peiqiu School of Chemistry and Life Science Anshan Normal University Anshan 114007 P. R. China Department of Chemistry Northeast Normal University Changchun 130024 P. R. China

A cost-effective and environmentally compliance FeCl3·6H2O catalyzed Friedel-Crafts alkylation of cyclic ketene dithioacetals with alcohols was developed. The reaction was efficient in the presence of catalyst loading as low as 5%（molar fraction） in CH2Cl2 solvent at room temperature or under reflux conditions. A wide range of alkylated ketene dithioacetals were synthesized in excellent yields.

关键词： Iron(Ⅲ) chloride Olefin Ketene dithioacetal Alcohol Friedel-Crafts alkylation

Late Ordovician mass extinction caused by global warming or cooling?

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Acta Geochimica 2020年第5期39卷 595-598页

作者： Renqiang liao Weidong Sun Institute of Oceanology Center for Ocean Mega-ScienceCenter of Deep Sea ResearchChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

The Late Ordovician mass extinction(LOME)was the first global extinction with the destruction of 85%of marine ***,the cause of LOME is still *** studies attribute it to large-scale volcanism caused by global cooling or *** analyzing the driving difference between global cooling and warming on large-scale magmatism,the perspective is intended to evoke a hot discussion on the cause of *** global cooling or warming trigger the LOME?

关键词： Late Ordovician Mass extinction Volcanism Glaciation

Diversity evolution and jump of Polo-like kinase 1 inhibitors

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Science China Chemistry 2013年第10期56卷 1392-1401页

作者： liao Chenzhong YAO RiSheng School of Medical Engineering Hefei University of Technology

Polo-like kinase 1 （Plkl）, a member of a family of serine/threonine kinases, is an attractive target for the development of anti- cancer drugs because it is involved in the regulation of cell-cycle progression and cytokinesis. This kinase provides two pock- ets for developing Plkl inhibitors： the N-terminal catalytic domain （NCD） and the polo-box domain （PBD）. For both of the two pockets, some natural products were identified as Plkl inhibitors and some synthetic Plkl inhibitors were developed by mimicking ATP and phosphopeptides, natural products binding to NCD and PBD respectively. This article not only reviews the progression of Plkl inhibitors binding to these two pockets, but also discusses diversity evolution and jump in the process of drug development using Plkl inhibitors as examples and how they impact on drug design and pharmacopbore modeling.

关键词： diversity evolution diversity jump Polo-like kinase 1 ATP mimics natural product

A Jury-Based Trust Management Mechanism in Distributed Cognitive Radio Networks

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China Communications 2015年第7期12卷 119-126页

作者： SU Wengui liao Yang School of Mechanical Engineering Guangxi University Data Center Bank of China Limited

In the trust management scheme of the distributed cognitive radio networks, the absence of the central control devices cause many problems such as a lack of standardized control for trust computation, and the absence of the decision makers in trust evaluation and collaborative decision making. A trust management mechanism based on the jury system for distributed cognitive radio networks is proposed in this paper. The "jury user" is designed to collaboratively examine the reputation of the cognitive user in the networks and to perform data fusion and spectrum allocation for distributed cognitive radio networks. Simulation analysis results show that the proposed scheme can ensure accuracy and fairness in trust evaluation and improve effectiveness and flexibility of spectrum allocation.

关键词： cognitive radio network trust scheme jury system distributed network trust evaluation

Epigenetic regulation of prostate cancer: the theories and the clinical implications

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Asian Journal of Andrology 2019年第3期21卷 279-290页

作者： Yiji liao Kexin Xu Department of Molecular Medicine University of Texas Health Science Center San Antonio TX 78229 USA Cancer Therapy and Research Center University of Texas Health Science Center San Antonio TX 78229 USA

Epigenetics is the main mechanism that controls transcription of specific genes with no changes in the underlying DNA sequences. Epigenetic alterations lead to abnormal gene expression patterns that contribute to carcinogenesis and persist throughout disease progression. Because of the reversible nature, epigenetic modifications emerge as promising anticancer drug targets. Several compounds have been developed to reverse the aberrant activities of enzymes involved in epigenetic regulation, and some of them show encouraging results in both preclinical and clinical studies. In this article, we comprehensively review the up-to-date roles of epigenetics in the development and progression of prostate cancer. We especially focus on three epigenetic mechanisms: DNA methylation, histone modifications, and noncoding RNAs. We elaborate on current models/theories that explain the necessity of these epigenetic programs in driving the malignant phenotypes of prostate cancer cells. In particular, we elucidate how certain epigenetic regulators crosstalk with critical biological pathways, such as androgen receptor (AR) signaling, and how the cooperation dynamically controls cancer-oriented transcriptional profiles. Restoration of a “normal” epigenetic landscape holds promise as a cure for prostate cancer, so we concluded by highlighting particular epigenetic modifications as diagnostic and prognostic biomarkers or new therapeutic targets for treatment of the disease.

关键词： androgen receptor signaling diagnostic/prognostic/predictive biomarkers epigenetic therapy epigenetics gene expression regulation prostate cancer

Bernoulli策略下具有可变休假速率的库存系统研究

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应用数学 2025年第1期38卷 156-169页

作者：廖昌裕李建军刘力维南京理工大学数学与统计学院江苏南京210094

本文提出短时休假、长时休假的概念,研究Bernoulli策略下具有可变休假速率、延迟休假和(s,S)补货策略的库存系统.当系统库存为空时,系统以概率1-q进入短时休假,以概率q进入一段延迟休假,若在延迟休假期间补货成功,则恢复正常工作,否则... 详细信息

本文提出短时休假、长时休假的概念,研究Bernoulli策略下具有可变休假速率、延迟休假和(s,S)补货策略的库存系统.当系统库存为空时,系统以概率1-q进入短时休假,以概率q进入一段延迟休假,若在延迟休假期间补货成功,则恢复正常工作,否则进入长时休假.利用Markov过程相关理论对该系统进行稳态分析,得到该系统的稳态分布和系统平均库存、平均顾客损失率等性能指标.此外,我们分析了模型的特例,利用遗传算法,获得了系统最优库存策略,通过数值算例,说明了系统参数对稳态性能指标和费用函数的影响.

关键词：库存系统延迟休假可变休假速率 (s,S)策略 Markov过程

Modulation of B-cell receptor and microenvironment signaling by a guanine exchange factor in B-cell malignancies

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Cancer Biology & Medicine 2016年第2期13卷 277-285页

作者： Wei liao Sanjai Sharma Division of Hematology-Oncology Greater Los Angeles VA Healthcare Center UCLA School of Medicine

Objective： Chronic lymphocytic leukemia （CLL） and mantle cell lymphoma （MCL） cells over-express a guanine exchange factor （GEF）, Rasgrf-1. This GEF increases active Ras as it catalyzes the removal of GDP from Ras so that GTP can bind and activate Ras. This study aims to study the mechanism of action of Rasgrf-1 in B-cell malignancies. Methods： N-terminus truncated Rasgrf-1 variants have a higher GEF activity as compared to the full-length transcript therefore a MCL cell line with stable over-expression of truncated Rasgrf-1 was established. The B-cell receptor （BCR） and chemokine signaling pathways were compared in the Rasgrf-I over-expressing and a control transfected cell line. Results： Cells over-expressing truncated form of Rasgrf-1 have a higher proliferative rate as compared to control transfected cells. BCR was activated by lower concentrations of anti-IgM antibody in Rasgrf-1 over-expressing cells as compared to control cells indicating that these cells are more sensitive to BCR signaling. BCR signaling also phosphorylates Rasgrf-1 that further increases its GEF function and amplifies BCR signaling. This activation of Rasgrf-1 in over-expressing cells resulted in a higher expression of phospho-ERK, AKT, BTK and PKC-alpha as compared to control cells. Besides BCR, Rasgrf-1 over-expressing cells were also more sensitive to microenvironment stimuli as determined by resistance to apoptosis, chemotaxis and ERK pathway activation. Conclusions： This GEF protein sensitizes B-cells to BCR and chemokine mediated signaling and also upregulates a number of other signaling pathways which promotes growth and survival of these cells.

关键词： B-ceU malignancies mantle cell lymphoma chronic lymphocytic leukemia (CLL) B-cell receptor guanine exchange factorRasgrf- 1 ERK pathway

On the stability of the three classes of Newtonian three-body planar periodic orbits

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Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2121-2126页

作者： LI XiaoMing liao ShiJun School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University Ministry-of-Education Key Laboratory in Scientific Computing Nonlinear Analysis and Applied Mathematics Research Group (NAAM) King Abdulaziz University (KAU)JeddahSaudi Arabia

Currently,the fifteen new periodic orbits of Newtonian three-body problem with equal mass were found by Suvakov and Dmitra sinovi[Phys Rev Lett,2013,110:114301]using the gradient descent method with double *** this paper,these reported orbits are checked stringently by means of a reliable numerical approach(namely the"Clean Numerical Simulation",CNS),which is based on the arbitrary-order Taylor series method and data in arbitrary-digit precision with a procedure of solution *** is found that seven among these fifteen orbits greatly depart from the periodic ones within a long enough interval of time,and are thus most possibly unstable at *** is suggested to carefully check whether or not these seven unstable orbits are the so-called"computational periodicity"mentioned by Lorenz in *** work also illustrates the validity and great potential of the CNS for chaotic dynamic systems.

关键词： unstable Newtonian verification chaotic digit carefully periodicity Clean enough arbitrary

Stability of stochastic differential equation with linear fractal noise

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Frontiers of Mathematics in China 2014年第3期9卷 495-507页

作者： Junjun liao Xiangjun WANG School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074 China

We study a class of stochastic differential equation with linear fractal noise. By an auxiliary stochastic differential equation, we prove the existence and uniqueness of the solution under some mild assumptions. We a... 详细信息

关键词： Fractional Brownian motion (FBM) stochastic differential equation (SDE) exponential p-stability λ-exponential p-stability