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111.
Parent-daughter transmission of the androgen receptor gene as an explanation of the effect of father absence on age of menarche 总被引:2,自引:0,他引:2
Based on an evolutionary theory of socialization, Belsky and colleagues proposed that girls exposed to a stressful environment, especially when due to father absence in the first 7 years of life, showed an early onset of puberty, precocious sexuality, and unstable relationships as adults. The authors of this article examined an alternative explanation that a variant X-linked androgen receptor (AR) gene, predisposing the father to behaviors that include family abandonment, may be passed to their daughters causing early puberty, precocious sexuality, and behavior problems. The results of a study of 121 White males and 164 White females showed a significant association of the short alleles of the GGC repeat polymorphism of the AR gene with a range of measures of aggression and impulsivity, increased number of sexual partners, sexual compulsivity, and lifetime number of sex partners in males; and paternal divorce, father absence, and early age of menarche in females. These findings support a genetic explanation of the Belsky psychosocial evolutionary hypothesis regarding the association of fathers' absence and parental stress with early age of onset of menarche and early sexual activity in their daughters. A genetic explanation of the father absence effect is proposed in which fathers carrying the AR alleles are more likely to abandon a marriage (father absence) and pass those alleles to their daughters in whom they produce an earlier age of menarche and behavioral problems. 相似文献
112.
Recent demographic trends and growth in the public sector of higher education have created severe strains for many private liberal arts colleges. The population ecology model, which explains the survival or demise of organizations in terms of their ability to negotiate for resources in their environment, provides a framework for assessing predictors of continued success among colleges. A three-way discriminant analysis based on the population ecology framework and other empirical research led to the successful classification of almost 72% of a sample of colleges in terms of their experiences during the 1970s. Number of departments, median state income, library holdings per enrollee, sectarian affiliation, annual tuition, Roman Catholic affiliation, and SAT composite score were found to be major predictors. 相似文献
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114.
Three experiments investigated conditioning of the rabbit’s nictitating membrane response (NMR) in a second-order conditioning procedure which intermixed first-order trials (CS1-US) and second-order trials (CS2-CS1) from the outset of training. Experiment 1 provided a controlled demonstration that substantial levels of second-order conditioning can be obtained with the NMR preparation. Experiment 2 showed that the level of CR acquisition to CS2 was an inverse function of the CS2-CS1 interval over the values of 400, 800, and 2,400 msec. Experiment 3 found that CR acquisition to CS2 and CS1 in second-order conditioning varied in a parallel fashion across CS1-US intervals. Similarly, Experiment 3A found that the level of CR acquisition to the two components of a serial compound (CSA-CSB-US) varied in a parallel fashion as a function of the CSB-US interval. The results of the CS2-CS1 and CS1-US interval manipulations were all predictable from the known CS-US interval effects in NMR conditioning with a single CS. The present results are discussed with regard to their implications for accounts of serial compound conditioning and second-order conditioning. 相似文献
115.
James E. McClure 《Assessment & Evaluation in Higher Education》2005,30(6):571-579
This paper considers whether student motivation might be impacted by the replacement of a straight (A, B, C, D, F) grading system with a plus/minus system (A, A?, B+ … D?, F). The data that are examined are from several undergraduate economics classes at a mid‐sized midwestern university in the United States. The data includes student characteristics, student performance and students’ choices of either a plus/minus or a straight grading system. In this admittedly small‐scale study students, who chose plus/minus grading, were not significantly more motivated than students who opted for straight grading. 相似文献
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117.
The Effects of Political Violence on Palestinian Children's Behavior Problems: A Risk Accumulation Model 总被引:4,自引:0,他引:4
Interviews with 150 Palestinian mothers and their children living amidst the Intifada in the West Bank were conducted to assess exposure to political violence and family negativity as risk factors associated with behavioral problems as measured by the Child Behavior Checklist. The number of risks present in the child's life was significantly correlated with the number of behavioral problems the child exhibited ( R = .53, p < .001). The analysis further examined the role of gender, age, and community context in moderating the impact of high levels of accumulated risk on children's behavioral problems. Under conditions of high accumulated risk, boys evidenced more problems than girls, and younger children exhibited more problems than older children. Community context (as indicated by a high or low level of political violence) was a significant factor for girls but not for boys. 相似文献
118.
Fourteen behavioral measures were ranked according to their ability to differentiate performances of a wild population of mice from three domestic inbred strains. These “wildness” rankings were then analyzed for their ability to predict genetic and Genotype by Environment interactions. Genetic parameters were derived from analysis of three inbred domestic strains and their three hybrid crosses via the diallel technique of genetic analysis. Genotype by Environment interactions were assessed both as mean differences in stock performances resulting from rearing in a laboratory vs naturalistic environment and as differences in environmental variability within stock genotypes. Behavioral characters ranking high on “wildness” failed to demonstrate any unitary pattern of Genotype by Environment interactions. The diallel genetic analysis revealed many examples of additive variation but relatively few examples of dominant variation. An extremely wide range of interactions occurred between genotype and rearing environments, with “wildness” and “developmental homeostasis” concepts both failing to account for all the observed interactions. 相似文献
119.
Heather Trommer-Beardslee Ann Dasen Wiline Pangle Jay Batzner 《Teaching Artist Journal》2019,17(1-2):45-50
In 2016, professors representing Biology, Dance, Music, and Theatre and dance program students created Dunes, a performance piece that depicts the ecological succession of Michigan's sand dunes. The process used to make this work is a direct representation of the steps that Team Hyena Puppet, a collective of teaching artists and scientists, takes in their science-based art collaborations, which are used to reflect on and depict scientific research and simultaneously teach student participants and audience members science through the performing arts. 相似文献
120.
How do scores from writing samples generated by computerized essay scorers compare to those generated by “untrained” human scorers and what combination of scores, if any, is more accurate at placing students in composition courses? This study endeavored to answer this two-part question by evaluating the correspondence between writing sample scores generated by the IntelliMetric™ automated scoring system and scores generated by University Preparation English faculty, as well as examining the predictive validity of both the automated and human scores. The results revealed significant correlations between the faculty scores and the IntelliMetric™ scores of the ACCUPLACER™ OnLine WritePlacer Plus test. Moreover, logistic regression models that utilized the IntelliMetric™ scores and average faculty scores were more accurate at placing students (77% overall correct placement rate) than were models incorporating only the average faculty score or the IntelliMetric™ scores. 相似文献