有机污染物麻醉毒性的定量结构活性相关研究

应用Gaussian-3(G3)理论计算了23种有机污染物的中性分子以及它们的阳离子和阴离子的优势构象,分别预测了它们的电离能和电子亲合能.同时得到相应的量子化学参数,如:分子最高占有轨道能、分子最低空轨道能、分子偶极矩和分子体积等,并将这些理化参数与有机污染物的麻醉毒性参数相关联.结果表明:有机污染物的麻醉毒性与分子的电离能和电子亲合能的差值、分子的偶极矩、分子的体积存在良好的多元线性相关性,并建立了有机污染物的定量结构活性相关方程.     

衬底效应对LiTaO_3薄膜制备的影响

用溶胶凝胶法在N型硅、P型硅、石英、铂、镍衬底上制备了钽酸锂(LiTaO3)薄膜,用XRD和SEM对钽酸锂薄膜性能参数进行了表征;发现掺杂少量环氧树脂能提高钽酸锂薄膜的均匀性,改善薄膜与衬底的粘附性;研究了衬底效应与薄膜厚度的关系,薄膜厚度超过0.2μm,Ni衬底的XRD峰值强度几乎不再出现,说明衬底对薄膜初始结晶取向有重要影响;利用不同衬底上生长钽酸锂薄膜,XRD研究结果表明:N型硅、P型硅、石英衬底上只能制备多晶钽酸锂薄膜,铂衬底上制备的钽酸锂薄膜在(012)晶向有强大的择优取向性,镍衬底上制备的钽酸锂薄膜有更好的C轴择优取向性,C轴择优取向系数可达0.082。     

An invariance principle for triangular arrays of dependent variables with application to autocovariance estimation

The invariance principle for triangular arrays of dependent variables is studied. We use the concept of mixingale, proposed by McLeish (1975). Uniform bounds are imposed on the growth of conditional expectations with respect to distant predecessors. The theorem is applied to invariance principles for autocovariance estimates based on triangular arrays of time-series data for weak mixing sequences and linear processes. Such results are required for bootstrap applications.     

第三类Tobit模型的半参数估计方法

本文给出第三类Tobit模型的一种新的半参数估计方法。在独立性假设下,利用主方程和选择方程中可观察受限因变量的条件生存函数所满足的关系式,构造第三类Tobit模型参数的一步联立估计量。在已知选择方程中参数一致性估计量的条件下,这种方法也可用于构造主方程模型参数 的两步估计量。本文证明了所提出的一步联立估计量和两步估计量的一致性和渐近正态性。实验模拟表明,我们提出的估计量在有限样本下具有良好表现,且一步联立估计量的有限样本表现优于或接近于Chen（1997）的估计量。     

Expanding economic protection to the elderly in Latin America

This article addresses the reforms introduced in Latin American pension systems that had the aim of increasing coverage beyond formal‐sector workers. For this purpose, fourteen representative regional experiences are analysed using a taxonomy based on features of the cases examined in terms of design, implementation and results. The findings show that, although the reforms share the goal of expanding coverage, there are significant differences deriving from the context in which they were originally designed, their goals, and the capacity available to implement them. The results are not homogeneous, and it is possible to identify some aspects in which policy decisions can lead to better or worse results.     

Convergence or divergence? How the financial crisis affected European pensioners

The Member States of the European Union entered the financial crisis with very different pension systems. Although the use of standard adequacy measures suggest small impacts from the crisis, alternative measures based on pension wealth estimates indicate stronger effects. While the largest continental systems were left relatively unscathed by the crisis, Mediterranean systems were cut back significantly. This should lead to considerable convergence in system generosity across countries. Despite the cuts, state pensions in the stressed economies should still be generous enough to keep the majority of pensioners out of relative poverty, but this depends on a relatively quick turnaround in labour market performance in these countries.     

一语、二语迁移对三语写作的影响

从一语作文水平、二语作文水平、一语译三语能力、二语译三语能力四个方面考察一语、二语迁移对三语写作的影响,利用单因素方差分析比较发现,一语作文水平、一、二语译三语水平对三语作文水平的影响存在阀限,超过一定的阀限则影响不明显,而二语写作对三语写作的影响是持久性的。需要保持一定的一语写作水平和翻译能力,发展二语写作能力,力求三语写作能力的提高。     

The Brazilian pension model: The pending agenda

To achieve national goals defined by the 1988 Brazilian Federal Constitution, cash benefits alone are insufficient in the absence of more robust social services to reduce inequalities and improve social cohesion. The Constitution, albeit of national importance and international significance, has not addressed many institutional and administrative weaknesses in the design of the national pension system. Although coverage has been increased and inequality reduced, these measures are not sufficient. Brazil's ambitions to further develop social policies (and, indeed, to live up to its accorded international status as a social policy leader) may be constrained by an over‐reliance on conditional cash transfers such as those provided under the Bolsa Família programme. Brazil faces a major political‐economy challenge in addressing all these issues because the policy reform process is difficult, and, more importantly, because of the embedded role of vested interests. Moreover, Brazil must tackle these issues in the face of growing fiscal pressures, which could weaken the current political legitimacy of social policy and undermine important recent successes.     

Analysis of the implementation of a social protection initiative to admit the poorest of the poor to mutual health funds in Burkina Faso

To enable mutual health funds to extend coverage to poor people, the Mutual Health Support Network (Réseau d’appui aux mutuelles de santé – RAMS) in 2012 launched an initiative in collaboration with the Ministry of Social Action and Solidarity (ministère de l’Action sociale et de la Solidarité nationale – MASSN) in Burkina Faso. This article reveals difficulties in the initiative's implementation, which resulted in the continued exclusion of poor people from health services. Poor people were required not only to make co‐payments, but also to accept a limitation of coverage to three episodes of illness per year. Additional challenges to service takeup were the geographical distance of the homes of some beneficiaries covered by a mutual fund agreement from a health centre and the failure by some health workers and managers of pharmacies to recognize the mutual membership card. A formal framework was lacking that brought together all the actors involved in planning and implementing the initiative. Those involved did not all have the same information. Each structure performed the tasks within its scope, according to its own interests, but without consulting the other parties, and there was no platform for discussing implementation difficulties.     

韩国的东亚金融合作战略及其对我国的启示

文章考察了韩国参与东亚金融合作的背景和战略措施,进而分析了其参与该项合作的主要动因.文章指出,韩国致力于实施其"东北亚经济中枢国家"战略,所以其关注的区域重点是东北亚.鉴于东亚金融合作的长期性和松散性,韩国将通过培育本国健全的金融产业,确立其区域金融中心地位,同时将继续积极参与东亚区域内的各种金融协调与合作.在金融体制改革、证券市场培育及外汇储备调整等方面的举措值得我国借鉴.