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1.
Preface     
Different from traditional tax audit, supervision with self-audit is a combination of audit by the taxpayer himself and audit by the tax authority. This paper mainly studies a taxpayer’s optimal policy of tax evasion under supervision with self-audit and its related properties, in order to deduce some effective suggestions and theoretical bases to restrain tax evasion. Assuming that only a certain proportion of evaded tax can be discovered when the audit is executed, the authors first formulate a static model with self-audit. This model is divided into two stages. At the first stage, taxpayers declare their taxes, then the tax authority chooses audit objects, based on a known probability, and announces the result; if the taxpayer is chosen, he will enter the second stage, during which he has a chance to pay the evaded tax and the corresponding late fees and then is audited by the tax authority. The authors show the existence and uniqueness of the optimal amount of tax evasion at the first stage and the optimal proportion to self-expose at the second stage. The authors also discuss the related properties of the interior solution, and do elasticity analyses on some parameters. Besides, the authors extend the static model into the corresponding two-period model, and study the existence and uniqueness of the solution of the extended model. Finally, under the assumption that tax evasion can only be discovered with a certain probability when the audit is executed, the authors formulate another static model with self-audit and investigate its properties. This research is partially supported by the National Natural Science Foundation of China under Grant Nos. 60674082, 70221001, and 70731003.  相似文献   
2.
Summary By comparing steroid sulphatase levels per se, and also ratios to -galactosidase, in 6 sets of mice — normal females, entire and castrated males both with and without exogenous testosterone administration — we obtained support for the contention that induction of this enzyme is in part controlled by male hormones.  相似文献   
3.
Summary -Terthienyl and 5 polyacetylenes were examined for chromosome damaging activity using Syrian hamster cells. None of these naturally occurring compounds induced sister chromatid exchanges and neither -terthienyl nor phenylheptatriyne induced chromosome aberrations.The authors wish to thank the National Science and Engineering Research Council for financial support of this research.  相似文献   
4.
Conclusion The multi-faceted content of the SHCM and its collection of rules and tables made it an important mathematical work not only in China, but also in Korea and Japan. This book clearly demonstrated Chu's predominant interest in the field of algebra and his contribution to the solution of numerical equations of higher degree, which was a prelude to his famous treatise the Ssu-yüan yü-chien.  相似文献   
5.
用子波变换分析方法实时监测视觉诱发电位的潜伏期   总被引:1,自引:0,他引:1  
诱发电位的实时监测在临床中有重要意义。本文提出利用多分辨率子波分析技术来实时监测视觉诱发电位的潜伏期。为克服随机噪声的影响,我们引入相邻响应的相关系数来修正所检测得的潜伏期的偏移,并应用前一次响应的波峰位置来决定当前的搜寻范围。实验表明,本方法能实时监测视觉诱发电位的潜伏期。  相似文献   
6.
 聚集诱导发光(AIE)从2001年提出到现在,经历了迅猛的发展。研究AIE的发光机理、设计合成新型的AIE分子,应用到人类生活的各个领域中是当前的研究热点。在生物医学应用上,AIE分子相比于传统的结构平面刚性的荧光材料具有优势。根据AIE的发光机理--分子内运动受限,研究者设计出多种点亮型的AIE探针,它们可以在生物检测中提供更低的背景和更可靠的信号。同时,由于未结合检测物的AIE探针具有低背景,使用AIE探针的应用还具有无需洗涤步骤的优点,大大节省了操作时间及减少检测样品的损失。检测形成的AIE聚集体具有优异的光稳定性和抗光漂白性,可以实现长时间的追踪和监测。目前,AIE生物探针在生物分子检测、细胞器成像、细菌成像、细胞追踪、血管成像、体内肿瘤成像与治疗等方面已经取得了众多的成果。本文介绍了AIE的提出、AIE的工作机理,AIE生物探针的构建,总结了AIE探针在生物成像、疾病诊断及治疗等不同方面的应用。  相似文献   
7.
Microtubules have pivotal roles in fundamental cellular processes and are targets of antitubulin chemotherapeutics. Microtubule-targeted agents such as Taxol and vincristine are prescribed widely for various malignancies, including ovarian and breast adenocarcinomas, non-small-cell lung cancer, leukaemias and lymphomas. These agents arrest cells in mitosis and subsequently induce cell death through poorly defined mechanisms. The strategies that resistant tumour cells use to evade death induced by antitubulin agents are also unclear. Here we show that the pro-survival protein MCL1 (ref. 3) is a crucial regulator of apoptosis triggered by antitubulin chemotherapeutics. During mitotic arrest, MCL1 protein levels decline markedly, through a post-translational mechanism, potentiating cell death. Phosphorylation of MCL1 directs its interaction with the tumour-suppressor protein FBW7, which is the substrate-binding component of a ubiquitin ligase complex. The polyubiquitylation of MCL1 then targets it for proteasomal degradation. The degradation of MCL1 was blocked in patient-derived tumour cells that lacked FBW7 or had loss-of-function mutations in FBW7, conferring resistance to antitubulin agents and promoting chemotherapeutic-induced polyploidy. Additionally, primary tumour samples were enriched for FBW7 inactivation and elevated MCL1 levels, underscoring the prominent roles of these proteins in oncogenesis. Our findings suggest that profiling the FBW7 and MCL1 status of tumours, in terms of protein levels, messenger RNA levels and genetic status, could be useful to predict the response of patients to antitubulin chemotherapeutics.  相似文献   
8.
9.
In recent years, supply chain management (SCM) has been in popularity as a new management philosophy for all industries, including textile and apparel industries. The textile-apparel supply chain is relatively complex because it encompasses many participants such as yarn manufacturers, fabric manufacturers, garment manufacturers and retailers. Although many scholars are engaged in researching SCM in textile and apparel industries, a systematic classification of textile-apparel chain does not exist. The paper proposes three types of textile-apparel chain, nominated vertical integration chain, traditional sourcing chain and 3P-hub (third party as the hub) chain. Different coordinators exist in different types of chain. Three Hong Kong headquartered companies, Esquel Group, TAL Apparel Ltd., and Li & Fang (Trading) Ltd. are used as cases responding to each type of the structures respectively.  相似文献   
10.
张元出生于1963年,1985年进入北京电影学院摄影系学习。他在1990年代初期拍摄完成的《妈妈》被认为是当代国内第一部“独立电影”。张元称得上是中国新生代导演群体中少有的“高产者”。在“浮出地表”之前,电影《北京杂种》《儿子》和《东宫.西宫》为他赢得了众多的国际声誉;而在1998年取得国际广播电影电视总局的“解禁令”之后,他又相继执导了影片《过年回家》《疯狂英语》《我爱你》《绿茶》《江姐》和《看上去很美》,也因此成为较早涉足国内电影商业化运作的一位新生代导演。作为新生代导演群体中的一类代表,张元的典型意义不仅在于他往返游走于“先锋”与“主旋律”之间的那份从容,而且“张元现象”也成为考量中国新生代导演十余年间辗转于电影美学与市场运作之间独特体验的生动样本。别有深意的是,这些细节都在某种特定的“全球化语境”中得到了更进一步的放大和渲染。本期邀约的四篇论文中,孙绍谊博士与李迅研究员提供的导演访谈尽可能地保留了许多现场交流的细节,使我们得以直接了解张元本人对于国内电影市场不无真诚又略显偏激的态度。这不仅是对读者反应式批评的有益补充,而且也正是本栏目所期冀的多元文体与多元研究路向的一次探索实践。刘福泉教授的《张元:在寻找中站立》秉承了传统美学批评的理路,以反叛、寻找、皈依为关键词,梳理张元从“小众”到“大众”乃至“主旋律”创作的心路历程。Adam Lam博士的《“第六代”:后现代文化的符码“仿真”》则通过对张元与另一位新生代导演管虎作品的比较研究,试图说明在“国际化”的巨型“能指”背后隐藏的权力运作机制。关于此问题,钱春莲、邱宝林二位博士合作完成的论文《论新生代电影导演的跨文化传播策略》提供出另外一种思路。论文从传播学的角度入手,探讨在经济全球化和文化全球化的双重维度上,新生代导演如何在直面市场的经济策略与以民族认同为基点的文化策略之间寻求微妙的平衡,并且将两岸三地青年导演的区域性合作纳入新生代电影的产业实践。这无疑开辟出一个新的研究路向,同时也呈现出一种新的合作发展的现实可能性。  相似文献   
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