ISSR markers based on GA and AG repeats reveal genetic relationship among rice varieties tolerant to drought, flood, or salinity

Drought,flood,salinity,or a combination of these limits rice production.Several rice varieties are well known for their tolerance to specific abiotic stresses.We determined genetic relationship among 12 rice varieties including 9 tolerant to drought,flood,or salinity using inter-simple sequence repeat (ISSR) markers.Based on all markers,the nine tolerant varieties formed one cluster distinct from the cluster of three control varieties.The salt-tolerant varieties were closest to two flood-tolerant varieties,and together they were distinct from the drought-tolerant varieties.(GA)8 YG was the most informative primer,showing the highest polymorphic information content (PIC) and resolving power (Rp).The drought-,flood-,and salt-tolerant varieties grouped in three distinct clusters within the group of tolerant varieties,when (GA)8 YG was used.Sabita was the only exception.The two aus varieties,Nagina22 and FR13A,were separated and grouped with the drought-and flood-tolerant varieties,respectively,but they were together in dendrograms based on other primers.The results show that ISSR markers associated with (GA)8 YG delineated the three groups of stress-tolerant varieties from each other and can be used to identify genes/new alleles associated with the three abiotic stresses in rice germplasm.     

用友ERP-U8院校版安装问题研究

针对学生在安装用友ERP-U8管理软件中存在的问题,结合实际应用经验对安装ERP-U8所需的操作系统和数据库的版本兼容性进行了分析,并给出了建设性的软件安装方案。     

Teachers’ perceptions of assessments of their mathematical knowledge in a professional development course

The purpose of the project reported in this article was to evaluate how assessing teachers’ mathematical knowledge within a professional development course impacted from the teachers’ perspective their learning and their experience with the course. The professional development course consisted of a 2-week summer institute and the content focus was geometry. We had decided to assess the mathematical learning of the teachers during this professional development course for various accountability reasons, but were concerned about possible negative by-products of this decision on the teachers and their participation. Thus, we worked to design assessment in ways that we hoped would minimize negative impacts and maintain a supportive learning environment. In addition, we undertook this evaluation to examine the impacts of the assessment, which included homework, quizzes, various projects, and an examination for program evaluation. Seventeen grade 5–9 teachers enrolled in the course participated in the study by completing written reflections and by describing their experiences in interviews. We learned that while our original intent was “to do no harm,” the teachers reported that their learning was enhanced by the assessment. The article concludes by describing the various properties of the assessments that the teachers identified as contributing to their learning of the geometry content, many of which align with current recommendations for assessing and evaluating grade K-16 mathematics students.

四种预处理因素的凝缩和抑制效应

比较研究了秋水仙素、8—羟基喹啉、对二氯苯、低温四种预处理因素对蚕豆根尖细胞染色体的凝缩效应和对有丝分裂的抑制效应。结果表明:(1)四种预处理因素积累中期细胞和使染色体凝缩的效应大小是:秋水仙素>低温>>对二氯苯>>8—羟墓喹啉。(2)秋水仙素对染色体的凝缩具有长效性,其它三种因素则是短效的。(3)8—羟基喹啉强烈抑制有丝分裂和细胞生长,并且难以恢复,使根尖细胞受到严重毒害。秋水仙素先是使有丝分裂受到抑制,之后又刺激有丝分裂。低温、对二氯苯也能抑制有丝分裂,但恢复较快。     

荧光光谱滴定法测定修饰环糊精与金刚烷衍生物的稳定常数

8-羟基喹啉修饰环糊精可发射8-羟基喹啉基团的荧光,环糊精和8-羟基喹啉基团存在自包结现象,当该修饰环糊精加入金刚烷衍生物后,金刚烷衍生物和修饰环糊精形成更稳定的包合物,可以把环糊精自包结的8-羟基喹啉基团顶出环糊精空腔,从而引起饰修环糊精荧光强度的变化。通过测定荧光强度的变化值,测得修饰环糊精与金刚烷衍生物配合物的稳定常数为LogKs=4.015。     

两种诱变剂对蚕豆根尖细胞遗传毒理学研究

以蚕豆根尖为材料，用微核实验和染色体畸变试验方法，研究不同浓度的8-羟基喹啉与对苯二酚对蚕豆根尖细胞的有丝分裂指数、微核率和染色体畸变率的影响．结果表明：不同浓度的8-羟基喹啉与对苯二酚使蚕豆根尖细胞有丝分裂指数明显增加，诱发较高频率的微核，在一定浓度范围内，其微核率随处理浓度的升高而升高，但随着诱变剂浓度的升高而呈下降趋势．两种诱变剂还能诱导染色体产生多种类型的畸变，染色体畸变率随着处理浓度的增加而升高，随着浓度的进一步增加却呈现下降趋势，但均明显高于对照组．     

3Cr2W8V模具钢球化退火工艺研究

分析模具凹模坯料用冷冲压制造型腔时开裂的原因，进行了几种3Cr2W8V模具钢球热处理软化工艺试验，观察了组织，测定了力学性能，获得实际生产中可行的3Cr2W8V模具钢球化退火工艺．     

过氧乙酸的制备方法与其稳定性的实验研究

为了分析、研究过氧乙酸生产中过氧化氢浓度、冰醋酸用量与不同稳定剂含量对产品稳定性的影响,对不同生产配方和加入稳定剂后的过氧乙酸产品在自然存放条件下的贮存稳定性进行了实验测定。结果显示,当过氧化氢与冰醋酸的配制比例为1:2时,过氧化氢浓度越高,过氧乙酸的产率越高;过氧乙酸浓度越高,贮存稳定性越差;1g.L-1的8-羟基喹啉或0.1%磷酸稳定剂可有效提高过氧乙酸的稳定性。     

论文化对翻译的操控现象

本文借鉴西方操控学派的研究视角,结合文化学、心理学、社会学的理论成果,探讨文化对于翻译的多层面操控的原因及表现.其中,宏观文化因素包括文化交流的客观需要、文化的性质和水平、民族的文化心理结构和文化的稳定性,微观文化因素包括道德、宗教和学术传统及其发展水平.在目前的社会历史条件下,增强操控的积极作用之根本方法是在坚持主旋律的前提下倡导文化及翻译的多样性.     

Stichwort: Bildungsökonomie und Qualität der Schulbildung

Keyword: Education Economics and Quality of Schooling. With reference to an earlier keyword article from the same author, this contribution looks at recent developments in education economics. The focus is a critical review of the field‘s contribution to research on the necessary conditions for high quality schooling. Of particular interest at the moment are the institutional framework conditions in a school system, which set incentives for performance. These are judged to be better than resource-based strategies of quality assurance. The empirical basis is provided by estimates of production functions using data from international school performance studies. This article will point out the limited validity of evidence gained through these studies and the – in sum – contradictory empirical findings. For this reason, political recommendations on the basis of this approach should be more reserved.