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91.
Previous research has established that SAT scores and high school grade point average (HSGPA) differ in their predictive power and in the size of mean differences across racial/ethnic groups. However, the SAT is scaled nationally across all test takers while HSGPA is scaled locally within a school. In this study, the researchers propose that this difference in how SAT scores and HSGPA are scaled partially explains differences in validity and subgroup differences. Using a large data set consisting of 170,390 students each of whom matriculated at one of 114 separate colleges, the researchers find that awarding SAT scores by ranking SAT within a high school generally results in substantial reduction in the size of subgroup mean differences for this predictor. However, validity for predicting first‐year GPA is also reduced by a small amount. Conversely, placing HSGPA onto a nationally normed metric through the use of multiple regression procedures results in a moderate increase in the size of subgroup mean differences, while also producing a small increase in validity. Taken together, these findings suggest that differences in predictor scaling can partially explain differences in the size of subgroup mean differences between HSGPA and SAT scores and have implications for predictive power.  相似文献   
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According to Healthy People (2011), in order to understand the health concerns of the Lesbian, Gay, Bisexual, and Transgender (LGBT), the oppression and discrimination that they have faced must be scrutinized. Among the many issues they face, their estrangement experiences are one of the most understudied. However, little is known about how it is experienced by the gay elderly population, hence, this investigation. This grounded theory purports to describe the process by which estrangement is experienced among the Filipino gay older adults. Strauss and Corbin’s Grounded Theory (1990) design was utilized. A total of 10 gay older persons were purposively chosen to participate in semi-structured interviews. Field texts were subjected to thematic analysis involving open, axial, and selective coding. The study generated The Sailing Model of Estrangement. Remarkably, three phases relative to estrangement emerged, namely: sequestering, striving, and surviving. Primarily, the sequestering phase involves the gay persons’ need to express self, search for acceptance, and its subsequent reactions. The striving phase typifies the struggle in dealing with estrangement leading to either feelings of depression, remorse and shame or positivity, hopefulness, and motivation. Finally, in the surviving phase, gay persons may either feel contented and fulfilled or sad, lonely, and remorseful as they acquiesce aging with estrangement. Findings of the study offer an understanding of how Filipino gay older adults employ coping strategies in response to estrangement.  相似文献   
94.
Book reviews     
Zwartjes, Otto, ed. La Sociedad andalusí y sus tradiciones literarias (Foro Hispánico, 7). Amsterdam: Rodopi, 1994.

Brincat, Joseph M. Malta 870–1054: Al‐Himyai's Account and its Linguistic Implications. Malta: Said International Ltd., 1995. 52pp.

Sells, Michael A. Mystical Languages of Unsaying. Chicago: The University of Chicago Press, 1994. 316 pp., US$18.95 (paperback), US$49.91 (cloth).

Diem, Werner, Arabische Geschäftsbriefe des 10. bis 14. Jahrhunderts aus der Österreichischen Nationalbibliothek in Wien (Documents Arabica Antiqua 1), 2 vols. Wiesbaden: Harrassowitz, 1995. Textband ix+518pp., Tafelband 76 plates.

Coope, Jessica A. The Martyrs of Cordoba: Community and Family Conflict in an Age of Mass Conversion. Lincoln: University of Nebraska Press, 1995. xvii+113 pp., US$ 25 (cloth).

Edwards, John. Religion and Society in Spain, c.1492 (Variorum Collected Studies Series: CS 520). Aldershot and Brookfield: Variorum, 1996. x+351 pp., US$ 97.00 (cloth).

Tolan, John Victor, ed. Medìeval Christian Perceptions of Islam. A Book of Essays (Garland Medieval Casebooks, Volume 10). New York and London: Garland Publishing, 1996. xxi+414 pp., US$60.00 (cloth).  相似文献   

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This article reviews the literature on evaluating international conferences identifying significant factors which contribute to measured success. Extensive previous research over the last twenty years has identified criteria for evaluating success which continue to be ignored as international conferences repeat the same mistakes. More systematic research is needed. A framework of 25 evaluation measures is described for future research on the assessment of international conferences.Responses to three items of a questionnaire sent out by the East-West Culture Learning Institute as part of a project studying international conferences are also discussed, relating to evaluation measures, problems of evaluation and potential benefits of evaluation. Guidelines and suggestions are provided synthesizing the available research toward planning more successful international conferences in the future. In conclusion, six issues are identified for further clarification in future research on international conferences.  相似文献   
97.
The antioxidants are essential molecules in human system but are not miracle molecules. They are neither performance enhancers nor can prevent or cure diseases when taken in excess. Their supplemental value is debateable. In fact, many high quality clinical trials on antioxidant supplement have shown no effect or adverse outcomes ranging from morbidity to all cause mortality. Several Chochrane Meta-analysis and Markov Model techniques, which are presently best available statistical models to derive conclusive answers for comparing large number of trials, support these claims. Nevertheless none of these statistical techniques are flawless. Hence, more efforts are needed to develop perfect statistical model to analyze the pooled data and further double blind, placebo controlled interventional clinical trials, which are gold standard, should be implicitly conducted to get explicit answers. Superoxide dismutase (SOD), glutathione peroxidase and catalase are termed as primary antioxidants as these scavenge superoxide anion and hydrogen peroxide. All these three enzymes are inducible enzymes, thereby inherently meaning that body increases or decreases their activity as per requirement. Hence there is no need to attempt to manipulate their activity nor have such efforts been clinically useful. SOD administration has been tried in some conditions especially in cancer and myocardial infarction but has largely failed, probably because SOD is a large molecule and can not cross cell membrane. The dietary antioxidants, including nutrient antioxidants are chain breaking antioxidants and in tandem with enzyme antioxidants temper the reactive oxygen species (ROS) and reactive nitrogen species (RNS) within physiological limits. Since body is able to regulate its own requirements of enzyme antioxidants, the diet must provide adequate quantity of non-enzymic antioxidants to meet the normal requirements and provide protection in exigent condition. So far, there is no evidence that human tissues ever experience the torrent of reactive species and that in chronic conditions with mildly enhanced generation of reactive species, the body can meet them squarely if antioxidants defense system in tissues is biochemically optimized. We are not yet certain about optimal levels of antioxidants in tissues. Two ways have been used to assess them: first by dietary intake and second by measuring plasma levels. Lately determination of plasma/serum level of antioxidants is considered better index for diagnostic and prognostic purposes. The recommended levels for vitamin A, E and C and beta carotene are 2.2–2.8 μmol/l; 27.5–30 μmol/l; 40–50 μmol/l and 0.4–0.5 μmol/l, respectively. The requirement and recommended blood levels of other dietary antioxidants are not established. The resolved issues are (1) essential to scavenge excess of radical species (2) participants in redox homeostasis (3) selective antioxidants activity against radical species (4) there is no universal antioxidant and 5) therapeutic value in case of deficiency. The overarching issues are (1) therapeutic value as adjuvant therapy in management of diseases (2) supplemental value in developing population (3) selective interactivity of antioxidant in different tissues and on different substrates (4) quantitative contribution in redox balance (5) mechanisms of adverse action on excess supplementation (6) advantages and disadvantages of prooxidant behavior of antioxidants (7) behavior in cohorts with polymorphic differences (8) interaction and intervention in radiotherapy, diabetes and diabetic complications and cardiovascular diseases (9) preventive behavior in neurological disorders (10) benefits of non-nutrient dietary antioxidants (11) markers to assess optimized antioxidants status (12) assessment of benefits of supplementation in alcoholics and heavy smokers. The unresolved and intriguing issues are (1) many compounds such as vitamin A and many others possessing both antioxidant and non-antioxidant properties contribute to both the activities in vivo or exclusively only to non-antioxidant activity and (2) since human tissues do not experience the surge of FR, whether there is any need to develop stronger synthetic antioxidants. Theoretically such antioxidants may do more harm than good.  相似文献   
98.
99.
从加拿大2001年的人口普查中抽取3%的样本数据,分析了原住民和非原住加拿大人之间工资和薪金的差异,发现注册印第安人、梅蒂斯人与非原住民的年收入和周薪在跨组和组内都有显著差异。这种差异在很大程度上是由于人口、人力资本、职业以及这三种人口的区域差异。  相似文献   
100.
Plant Growth Promoting Rhizobacteria   总被引:1,自引:0,他引:1  
Plant Growth Promoting Rhizobacteria (PGPR) are a group of bacteria that enhances plant growth and yield via various plant growth promoting substances as well as biofertilizers. Given the negative environmental impact of artificial fertilizers and their increasing costs, the use of beneficial soil microorganisms such as PGPR for sustainable and safe agriculture has increased globally during the last couple of decades. PGPR as biofertilizers are well recognized as efficient soil microbes for sustainable agriculture and hold great promise in the improvement of agriculture yields.  相似文献   
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