吕集版本考述

吕温是中唐进步的文学家、政治家和思想家。其独具一格的诗文创作在中唐文坛是举世瞩目的。本文试对其诗文集的版本渊源嬗变作一番考察,认为其文集版本自明清以来可大致归类为两大系统,即冯本和吴本系统。     

转基因产品低水平混杂问题研究

转基因产品低水平混杂(LLP)是随着转基因作物商业化而出现在进出口贸易中的一个现实问题,也是当前多边贸易谈判中的一个前沿议题,近年来已成为各国政府共同的政策关注点。作为转基因作物研发、种植和农产品贸易大国,我国农业产业的多个方面都将受到转基因产品LLP的影响。文章分析了转基因产品LLP的演进逻辑,探讨了现行LLP定义的政策含义;从技术和政策层面出发,论证了进口国对转基因产品的特殊关注是LLP问题出现的根本原因,提出了加强双边合作与互认的解决思路;从进出口两方面分析了LLP问题和LLP风险管理策略的缺失对一国农业产业产生的影响,并针对其经济风险评估和政策制定提出了建议。     

消费者对转基因食品健康风险与生态风险认知实证研究

采用武汉市消费者抽样调查所获取的横截面数据,分析了消费者对GMF健康风险和生态环境风险的认知现状,并利用有序分类的Logistic回归模型研究了影响风险认知的主要因素。结果表明:大多数消费者对于GMF在人类健康和生态环境的风险认知上持中立态度,而消费者的受教育程度、是否涉及生物科技职业、对GMF了解程度、信息来源渠道、对GMF优缺点认识、对GMF食品标签关注度以及对GMF信任度等因素都对健康与生态风险认知产生显著影响。     

我国养老机构空间布局特征及其优化

基于ArcGIS软件,运用空间分析法,从公平性和均衡性视角,对全国31个省市（不包括港澳台地区）养老机构的空间布局特征展开研究,探究我国养老机构整体发展历程与演化特点,并利用改进的两步移动搜索法对各县域养老机构的空间可达性进行测算。结果表明：我国养老机构的发展历程可划分为萌芽期（1949—1977年）、增长期（1978—1998年）、规范期（1999—2008年）和建设期（2009—2020年）四个阶段,各阶段具有不同的分布特征;养老机构总体区域分布差异较大,主要集中在东部和中部地区,而西部地区较为分散,供给水平尚未达到预期目标值;我国养老机构空间分布出现多个聚集核心,布局总体呈“品字形”分布,密度由聚集中心向周边地区逐渐递减;按规模划分有效服务半径评价养老机构的空间可达性更为有效,我国东南部地区的可达性明显优于西北部地区,西北部多数为可达性低值区,养老机构资源配置有待进一步完善。     

铜在8—羟基喹啉修饰铅笔芯电极上的伏安特性

本文用8-羟基喹啉修饰的铅笔芯电极研究了铜的阶梯阳极溶出伏安特性并将此法用于人发中微量铜的测定。实验指出,在此修饰电极上,铜的阶梯溶出峰有两个,1~#峰电位在-0.03V,2~#峰电位在0.27V 处。同样的试液和条件下,1~#峰总比2~#峰的峰电流大。实验研究了测定铜的最佳条件,并测得铜的浓度在4.0×10~(-8)～1.6×10~(-6)mol·L~(-1)范围内,1~#峰的峰高与浓度呈良好的线性关系,最低检测限为2×10~(-8)mol.L~(-1)。2~#峰高与铜的浓度在6.0×10~(-8)～1.6×10~(-6)mol·L~(-1)范围内也有较好的线性关系,也可用于测定铜。本文还分析了铜在修饰电极上的反应机理。@韦璐$本文用8-羟基喹啉修饰的铅笔芯电极研究了铜的阶梯阳极溶出伏安特性!并将此法用于人发中微量铜的测定。实验指出,在此修饰电极上,铜的阶梯溶出峰有两个,1~#峰电位在-0.03V,2~#峰电位在0.27V 处。同样的试液和条件下,1~#峰总比2~#峰的峰电流大。实验研究了测定铜的最佳条件,并测得铜的浓度在4.0×10~(-8)～1.6×10~(-6)mol·L~(-1)范围内,1~#峰的峰高与浓度呈良好的线性关系,最低检测限为2×10~(-8)mol.L~(-1)。2~#峰高与铜的浓度在6.0×10~(-8)～1.6×10~(-6)mol·L~(-1)范围内也有较好的线性关系,也可用于测定铜。本文还分析了铜在修饰电极上的反应机理。     

小学英语课堂会话中的语言错误、纠正反馈语和修正后的可理解输出

本文利用10节课堂会话语料探讨了小学课堂会话中学生语言错误、教师纠正反馈语和学生修正后的可理解输出之间的关系。数据表明,优秀教师针对学生语言错误而选用的纠正反馈语是有规律的,他们倾向针对学生的语法错误使用明确纠正法,针对词汇、语音错误使用形式协商法。这种针对性能推动学生产生修正后的可理解输出。     

Who Does the Public Trust? The Case of Genetically Modified Food in the United States

Trust is important for the perception of many types of risk, including those relating to genetically modified (GM) food. Who the public trusts in any given circumstance, however, is not well understood. In this study of public trust regarding GM food, an exploratory factor analysis with Promax rotation reveals public classification of three common institutional types-evaluators, watchdogs, and merchants. The structure of relationships among these stakeholders can act to enable or constrain public support for this new technology. Evaluators-scientists, universities, and medical professionals-are the most trusted. Watchdogs-consumer advocacy organizations, environmental organizations, and media sources-are moderately trusted. Merchants-grocers and grocery stores, industry, and farmers-are least trusted. While the federal government is seen as closest to being an evaluator, it is not highly correlated with any of the factors. The lack of trust in the organizations with the greatest resources and responsibilities for ensuring the safety of GM food should be seen as an important obstacle to the adoption of the technology.     

改型Wiggler自由电子激光谐波产生的非线性理论

建立了改型Ｗｉｇｇｌｅｒ自由电子激光的非线性理论。导出了自洽非线性方程组。用计算机模拟了在改型Ｗｉｇｇｌｅｒ磁场中，电子与光场互作用从线性调制到非线性饱和的演化过程，得到了电子的相空间群聚图、高次谐波的增益、抽取效率和电子束的分布函数。同时还研究了电子束的能散度对高次谐波的增益和效率的影响等。模拟结果证实，改型ｗｉｇｇｌｅｒ自由电子激光是实现短波长相干光辐射的重要途径之一。     

Socio-educational work in at-risk contexts and professional reflexivity: the multi-vision group of “Maestri di Strada”

ABSTRACT

The Association ‘Maestri di Strada’ (MdS) undertakes socio-educational interventions to promote the well-being of young people in the ‘high-risk’ suburbs of Naples. The socio-educational work is not a mere ‘technical-rational’ activity and it relies on the use of ‘self’, which is not an unlimited resource. MdS places great emphasis upon reflexivity after the action and adopts the ‘Multi-Vision Group’ (MVG), which is a modified Balint group, as a support mechanism for its staff. Before trainees begin working, they attend the MVGs, observe them, and provide narrative accounts of the process. In this study, 61 reports prepared by the trainees during an academic year underwent a textual analysis. The aim was to evaluate the reflexive function of the group and the results indicate that, within the MVG, the practitioners express emotions, doubts, and difficulties linked to the job and its high-risk contexts. They show both self-awareness and awareness of the importance of the team, thinking as a community in a cooperative way. These are features related to reflexivity, which is recognised as being crucial for practice; the process of observation and recording also has a high educational importance for the trainees and social work students.     

Maximum likelihood estimators of the location and scale parameters of the exponential distribution from a censored sample

In this note explicit expressions are given for the maximum likelihood estimators of the parameters of the two-parameter exponential distribution, when a doubly censored sample is available.