防污损涂料添加剂Irgarol-1051降解产物对H4IIE鼠肝癌细胞的基因影响(英文)

为研究海洋防污损涂料添加剂Irogarol-1051的降解产物M2的基因毒性,应用微阵列技术,选取Affymetrix公司鼠基因组230 2.0基因芯片检测30μmol/L M2暴露下的鼠肝癌细胞基因表达变化.实验结果显示,96 h的M2暴露导致了38个基因在全部4组可能的对照/暴露中均发生显著变化(p0.002 5),其中只有Accn5基因研究较为透彻,该基因表达的抑制可能影响上皮钠通道的功能.此外,分别有10和82个功能注释基因在至少一组对照/暴露组中上调和下调.M2诱导的基因主要和细胞核(细胞成分)相关.M2抑制的基因则主要影响生物过程中的G蛋白偶联信号通路功能和细胞成分中的细胞膜内整合功能.     

Teaching writing to middle school students: a national survey

A random sample of language arts, social studies, and science middle school teachers from the United States were surveyed about their preparation to teach writing, beliefs about responsibilities for teaching writing, use of evidence-based writing practices, assessment of writing, use of technology, and adaptations for struggling writers. The findings from this survey raised concerns about the quality of middle school writing instruction. Many teachers believed their preservice and inservice preparation to teach writing was inadequate. Middle school students spend little time writing or being taught how to write. While most teachers used a variety of evidenced-based writing practices and made adaptations for struggling writers, such methods were applied infrequently. Most teachers did not appear to use assessment data to shape how they taught writing, and computers played a relatively minor role in middle school writing instruction. Even though teachers generally agreed that writing was a collective responsibility, language arts teachers placed a greater emphasis on writing instruction than social studies and science teachers.     

The Status of Genetics Curriculum in Higher Education in the United States: Goals and Assessment

We review the state of genetics instruction in the United States through the lens of backward design, with particular attention to the goals and assessments that inform curricular practice. An analysis of syllabi and leading textbooks indicates that genetics instruction focuses most strongly on foundations of DNA and Mendelian genetics. At the same time, a survey of faculty indicates that other concepts, such as the application of genetics to society or the environment, are viewed as equally or even more important than foundation concepts. This disconnect suggests a need for more explicit goal setting prior to curriculum development. We also review the relationship between concept inventories, multiple-choice tests measuring conceptual understanding, and curricular goals. Existing concept inventories offer a strong foundation on which to build community-developed concept assessments of genetics knowledge. Concept assessments such as these would allow the genetics education community to test hypotheses of curricular change.     

The Student–Teacher Relationship Scale revisited: Testing factorial structure,measurement invariance and validity criteria in German-speaking samples

The Student–Teacher Relationship Scale (STRS) is widely used for research in kindergarten and school. The increasing number of applications inside and outside of the U.S. stresses the need to investigate STRS properties, accordingly. The present study used the STRS in German-speaking countries, examining whether (a) the original factor structure is appropriate for a German version, (b) whether applications of a German STRS are invariant across contexts (kindergarten, first and second grade) as well as gender, and (c) whether construct and criterion validity are met. The original STRS was translated into German and filled out by 368 kindergarten and 503 elementary school teachers in Germany and Austria. Observations in kindergartens, student reports in schools, and teacher reports of students’ characteristics served as validity criteria. Results of confirmatory factor analyses (CFAs) did not confirm the original STRS factor structure. Subsequent exploratory factor analyses on training samples resulted in significant item reductions, followed by further CFAs on validation samples. The bootstrapped results yielded an adjusted three-factor model with subscales indicating satisfying alphas and invariance across context and gender. Construct and criterion validity were met for all subscales of the German STRS based on various criteria from both, observations and reports.     

Politeness theory and refusals of requests: Face threat as a function of expressed obstacles

This investigation seeks to extend Wilson, Aleman, and Leatham's (1998) revision of Brown and Levinson's (1987) politeness theory by focusing on the relationship between face threat and refusals to requests. Results support that (a) when requests are refused, threats to the negative face needs of the requester are more prevalent than threats to the negative face of the refuser and (b) depending on the obstacle underlying the refusal, there are differences in type of threat present to the requester's positive face and the refuser's face needs.     

Relational Maintenance and the Influence of Commitment in Online and Offline Relationships

The study of relational-maintenance behaviors has sometimes included the impact of medium as a peripheral variable, but rarely has the impact of medium been tested directly. Participants (N = 1336) delineated themselves into four separate groups depending on the initial and continued use of mediated communication. They reported their use of relational-maintenance behaviors, as well as feelings of commitment towards the relationship. The medium had an impact on the use of relational-maintenance behaviors, primarily between people who had only met their partners in a mediated environment and those who had met them face-to-face. However, commitment level appears to strongly moderate the relationship between group and use of maintenance behaviors.     

Adlai E. Stevenson's United Nations audience

As United States Ambassador to the United Nations, Stevenson, with the assistance of his staff, analyzed and prepared to address three widely varied audiences: the primary audience, his fellow diplomats; his secondary audience, representatives of the world press and the radio and television media; and a spontaneous and ever‐changing group of daily visitors. To influence these audiences and to seek the widest level of support and the least antagonism for American policies, Stevenson had to concern himself with their functions, attitudes, and loyalties.     

Evaluating Group Use of the Information Commons

Evaluating the effectiveness of an information commons has been discussed in many venues since the concept was first implemented. The Harold B. Lee Library at Brigham Young University confronted this same struggle. After two years of activity, the information commons had not been assessed to see whether the purposes for which it was planned were being fulfilled. This paper describes its first assessment. Measuring the number of groups who used the information commons over the period of two years, the assessment showed that indeed the commons is being used to a great extent for group work, one of the goals set for the creation of the information commons.     

Foreign and International

Isaiah Litvak and Christopher Maule's Cultural Sovereignty, The Time and Reader's Digest Case in Canada (New York: Praeger Special Studies, 1974---$13.50)

Survey of Public Attitudes Towards the Computer (Ottawa: Department of Communications, 1973---$1.00, paper)

Bernard Rubin's Propaganda and Public Opinion: Strategies of Persuasion (Middletown, Conn.: Xerox Educational Publications, 1973---copies on request, paper)

Jim Richstad, Michael McMillan, and Ralph Barney's The Pacific Islands Press: A Directory (Honolulu: University Press of Hawaii, 1973---no price given, paper)

Judith Tegger Kildow's Intelsat: Policy-Maker's Dilemma (Lexington, Mass.: Lexington Books/Heath, 1973---$12.50)