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71.
In order to change the attitude of early adolescent female and male students toward scientists and women in science, students in the middle school/junior high grades were exposed over a two months' period to women science career role models as part of their science instruction. This treatment positively affected the students' attitude toward scientists and toward women in science. It is suggested that teachers of science in the middle school/junior high should periodically bring community resource people who use science in their careers to the classroom to act as role models and that women should be included among this group so that the attitudes of both male and female students toward scientists and women in science might be improved.  相似文献   
72.
A new item parameter replication method is proposed for assessing the statistical significance of the noncompensatory differential item functioning (NCDIF) index associated with the differential functioning of items and tests framework. In this new method, a cutoff score for each item is determined by obtaining a (1 −α) percentile rank score from a frequency distribution of NCDIF values under the no-DIF condition by generating a large number of item parameters based on the item parameter estimates and their variance-covariance structures from a computer program such as BIILOG-MG3. This cutoff for each item can be used as the basis for determining whether a given NCDIF index is significantly different from zero. This new method has definite advantages over the current method and yields cutoff values that are tailored to a particular data set and a particular item. A Monte Carlo assessment of this new method is presented and discussed.  相似文献   
73.
The low achievement of Native American students, as measured by standardized tests, results from a number of factors, including the lack of cultural relevance of curriculum materials used in their instruction. Using a pretest–posttest control group design, Native American students in Bureau of Indian Affairs schools in Grades 4–8 who were taught science using culturally relevant materials achieved significantly higher and displayed a significantly more positive attitude toward Native Americans and science than comparable students who were taught science without the culturally relevant materials. It is suggested that when educators of Native Americans teach science, they should use materials that incorporate frequent reference to Native Americans and science.  相似文献   
74.
Private for-profit higher education has been rapidly expanding in developing countries worldwide since the early 1990s. This global trend has been particularly evident in Ethiopia, where only three public universities existed until 1996. By 2005, about 60 private for-profit higher education institutions had been founded in Ethiopia. This has led to mixed feelings among the Ethiopian public. While some laud the opportunities and advantages these new institutions bring, others are apprehensive that the quality of education might be compromised by an expansion motivated by monetary gain. This article sheds light on these paradoxes and provides suggestions for policy and practices.  相似文献   
75.
76.
    
In this paper a variety of optimal control (OC) problems for distributed- parameter (DP) systems are approached using mathematical programming (MP). First, the principal DP models in current use are given, a variety of DP objective functions is provided, and the OC problems based on them are formulated. Second, these models and objective functions are converted in algebraic form, as required by MP, and the solution procedure of the OC problems via MP is outlined. Third, a representative set of nonlinear programming results applied to DP systems is presented, and finally, a numvber of application examples is given.  相似文献   
77.
    
Ethics and Information Technology - Under what circumstances if ever ought we to grant that Artificial Intelligences (AI) are persons? The question of whether AI could have the high degree of moral...  相似文献   
78.
Given the paucity of studies conducted to know the effect of suddenness and earlier onset of endocrinological changes associated with hysterectomy, on the serum and urinary levels of calcium, magnesium and phosphate the present study was conducted to compare the levels of calcium, magnesium and phosphate in serum and urine of hysterectomised and natural menopausal south Indian women. This is a cross-sectional observational study. The study included three groups of 30 healthy premenopausal, 30 early surgical menopausal and 30 natural post menopausal women. Women suffering from any endocrine disease were excluded. Analysis was performed in serum and urine sample. The levels of calcium, magnesium and phosphate in serum and calcium/creatinine, magnesium/creatinine and phosphate/creatinine ratio were estimated in urine by spectrophotometric method. Hysterectomised women (serum calcium: 8.7 ± 0.09 mg/dl; urine calcium/creatinine: 0.16 ± 0.02) have significantly low serum calcium (p < 0.001) and high urinary calcium/creatinine (p = 0.002) ratio and post menopausal women (serum magnesium: 2.1 ± 0.03; serum phosphate: 4.4 ± 0.16; urinary calcium/creatinine: 0.17 ± 0.02; urinary magnesium/creatinine: 0.09 ± 0.01) have significantly high serum magnesium (p = 0.016), serum phosphate (p = 0.043) and high urinary calcium/creatinine (p = 0.002), magnesium/creatinine ratio (p = 0.025) compared to healthy pre menopausal women. Post menopausal women (serum calcium: 9.1 ± 0.08) have significantly high serum calcium and phosphate compared to hysterectomised women (serum phosphate: 3.93 ± 0.11). Hysterectomised women have significantly low serum calcium, oestrogen and high urinary calcium/creatinine ratio compared to healthy premenopausal women and low serum calcium and low serum phosphate compared to natural postmenopausal women. Natural postmenopausal women had low serum oestrogen and high serum magnesium, serum phosphate, urinary calcium creatinine ratio and urinary magnesium creatinine ratio compared to healthy premenopausal women.  相似文献   
79.
OBJECTIVE: This study had two aims: First to examine psychosocial correlates of child maltreatment risk, and second to assess the validity of the CAP Inventory (Milner, 1986) with multiply disadvantaged teenage mothers. METHOD: Participants were 75 adolescent mothers who were wards of the Illinois child protection system. Mothers (aged 14-18) and infants participated in home-based psychosocial assessment of personal and parenting functioning. Group comparisons examined differences for mothers with elevated versus normal versus invalid CAP scores due to faking good. RESULTS: Findings indicated that abuse risk groups differed on emotional distress, social support satisfaction, reading achievement, and years of education, but not on parenting beliefs or quality of child stimulation. Differences favored the normal over the elevated risk group in all significant comparisons, whereas mothers with elevated faking good differed from normals only in lower reading achievement. Multiple regression analysis highlighted emotional distress, support dissatisfaction, and low achievement as significant predictors of greater abuse risk. CONCLUSIONS: Despite sharing multiple disadvantages, adolescent wards are a heterogeneous group who show different levels of psychosocial functioning corresponding to levels of child maltreatment risk. The findings provide support for the concurrent validity and clinical applicability of the CAP Inventory with disadvantaged teenage mothers.  相似文献   
80.
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