Charmonium and charmoniumlike states at the BESIII experiment

Charmonium is a bound state of a charmed quark and a charmed antiquark, and a charmoniumlike state is a resonant structure that contains a charmed quark and antiquark pair but has properties that are incompatible with a conventional charmonium state. While operating at center-of-mass energies from 2 to 5 GeV, the BESIII experiment can access a wide mass range of charmonium and charmoniumlike states, and has contributed significantly in this field. We review BESIII results involving conventional charmonium states, including the first observation of the M1 transition ψ(2S) → γη_c(2S) and the discovery of the ψ₂(3823) state; and report on studies of charmoniumlike states, including the discoveries of the Z_c(3900) and Z_c(4020) tetraquark candidates, the resolution of the fine structure of the Y(4260) state, the discovery of the new production process e⁺e⁻ → γX(3872) and the uncovering of strong evidence for the commonality among the X(3872), Y(4260) and Z_c(3900) states. The prospects for further research at BESIII and proposed future facilities are also presented.     

斯图尔特·帕特里克的失败国家理论研究

美国学者斯图尔特.帕特里克的失败国家理论研究值得深思。他运用＂能力＂与＂意愿＂双重维度对失败国家理论进行的辨析正名,他同布鲁金斯学会高级研究员苏珊.赖斯（Susan Rice）联袂发布的《2008年第三世界脆弱国家指数》,他对美国严重依赖国防部来解决失败国家问题的批评,他对应对失败国家问题＂全政府＂（whole of government）方略的提倡,均显示了深厚精湛的学识和卓尔不群的理论创造能力。     

浅谈调适心理状态的思想教育方略

人的心理状态的变化对一个人的思想和行动往往会有直接的影响。心理状态是思想工作的重要依据 ,不同的心理状况需要不同的思想教育方法 ,这就要善于调查分析心理活动 ,了解和把握人的心理状态 ,创造良好的心理活动的客观环境 ,积极引导心理发展 ,巩固和发展积极心理因素 ,形成和保持一种良好的心理状态。     

一类生态-流行病模型正平衡解的存在性

考虑一类捕食者带有传染病并具有Holling-Ⅱ功能性反应函数的生态-流行病模型.讨论其带有扩散项的在齐次Neumann边界条件下问题.主要考虑其对应的平衡态问题的正解的存在性.首先应用最大值原理和Harnack不等式给出其反应扩散问题的正平衡解的先验估计(正的上下界估计),然后应用能量方法给出了该问题非常数正平衡解的...     

Sharing best practices in Barbados and Trinidad and Tobago: patterns of policy implementation and resistance

This article outlines policies from multilateral organisations that advocate sharing best practices between developing nations. The article discusses the degree to which these best practices are implemented by small states as indicated by teachers, academics and policymakers in Barbados and Trinidad and Tobago. For the purpose of this article, a best practice refers to pedagogy, curriculum or programme that contributes to student achievement. Currently, a number of influential multilateral organisations advocate that developing nations should share their best practices in education with each other. Despite encouragement by multilaterals however, best practices are not shared. At best, foreign ideas are used to legitimise local policies. While these policies are intended to help countries reach their Education for All (EFA) goals, they do not account for the differences between islands and their vulnerability towards larger countries. Attempts to innovate the curriculum by implementing foreign ideas failed due to the forces of tradition. It can thus be concluded that resistance – non‐compliance or opposition – to sharing educational best practices, as well as to the implementation of new curricula, stems from echoes of colonialism and globalisation. Although this study focuses on two islands, there are implications for other developing countries and small states as they fall under the same policy auspices of UNESCO and the Commonwealth Secretariat.     

四夸克态的味及自旋波函数构造

根据夸克的SU（2）自旋对称性和u、d、s夸克的SU（3）味对称性,利用群论和张量的方法构造了四夸克态qqqq的味及自旋波函数。     

混态不确定性关系的实验检验

不确定关系是量子理论的核心内容之一,体现为不相容物理量的测量不确定性之间存在着此消彼长的内在平衡关系。截至目前,众多不确定关系在各种物理系统中进行了实验验证,其中绝大多数实验是在纯态量子系统中进行的。本文在相干光制备的偏振混态系统中对直和形式的控制不等式型（majorization）不确定关系进行实验研究。通过测量偏振光束的斯托克斯参量,实验验证混态直和形式不确定关系。结果表明,所检验的控制不等式不确定关系对于一般的混态系统是最优的。     

失败国家理论粉饰美国建立非洲司令部

9·11事件后,强调主权国家应该具有良好治理能力和责任的失败国家理论成为美国对非政策的指导思想,美国据此加强对了对非军事援助,最终建立了非洲司令部,但其主要目的则是要假借非洲国家和非盟之手来保卫非洲石油安全和遏制中国。     

西方大学图书馆绩效评估标准及其方法

绩效评估是当前大学图书馆建设的一个重要课题,当代西方十分注重大学图书馆绩效评估工作,建立了很多新的标准和方法,大大推进了现代图书馆的建设。     

战后西方发达国家家庭政策的嬗变

在战后福利国家发展的黄金时期,西方发达国家的家庭政策也得到了扩展,其福利提供的普遍性与覆盖范围的广泛性特征日益明显。但自60年代中期以后,伴随着贫困的再发现以及妇女运动浪潮的高涨,西方发达国家的家庭政策开始呈现出针对性的特征。这是发达国家为适应战后政治经济社会形势的变迁而做出的符合逻辑的选择结果。