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61.
Recent experiments have been used to “edit” genomes of various plant, animal and other species, including humans, with unprecedented precision. Furthermore, editing the Cas9 endonuclease gene with a gene encoding the desired guide RNA into an organism, adjacent to an altered gene, could create a “gene drive” that could spread a trait through an entire population of organisms. These experiments represent advances along a spectrum of technological abilities that genetic engineers have been working on since the advent of recombinant DNA techniques. The scientific and bioethics communities have built substantial literatures about the ethical and policy implications of genetic engineering, especially in the age of bioterrorism. However, recent CRISPr/Cas experiments have triggered a rehashing of previous policy discussions, suggesting that the scientific community requires guidance on how to think about social responsibility. We propose a framework to enable analysis of social responsibility, using two examples of genetic engineering experiments.  相似文献   
62.
The 12-item short form of the Buss-Perry Aggression Questionnaire (BPAQ-SF) was originally developed by Bryant and Smith (2001) and modified and confirmed using confirmatory factor analysis with mentally ill offenders by Diamond, Wang, and Buffington-Vollum (2005). In the current study, construct validity of the BPAQ-SF was assessed with a sample of 1,181 male and 435 female general population federal offenders. Confirmatory factor analysis supported the four-factor structure. Tests confirmed factorial invariance across gender for all loadings and covariances. Reliabilities were found to be adequate and comparable to those found in the studies cited above. Concurrent validity was supported by high correlations between the subscales of the BPAQ-SF and several relevant subscales on the Personality Assessment Inventory (PAI). In addition, those offenders with prior history of violence, head injuries, childhood abuse, residential treatment, custody, or foster care as a child had higher scores on the BPAQ subscales.  相似文献   
63.
In the present study, we investigated age-related changes in interactions between efficiency of neuronal repair mechanisms and efficiency of cholinergic neurotransmission in the context of attentional orienting. In addition, we explored white matter volume changes as possible neuronal underpinnings. A sample of 230 healthy middle-aged (53–64 years) and older (65–75 years) adults was genotyped for polymorphisms of APOE and CHRNA4, a nicotinic receptor subunit gene. Participants were administered a visuospatial attention task involving letter discrimination with location cues of varying validity. Genotype effects on white matter volume were also investigated in a subset of participants who received MRI scans. APOE interacted with CHRNA4, such that APOE-ε4 carriers who were also CHRNA4 TT homozygotes showed disproportionately slowed reaction time (RT) following invalid location cues. The interaction was stronger in the middle-aged participants than in the older participants. There was also a trend for individuals with combined APOE-ε4/CHRNA4 TT genotypes to show both lower white matter volume and slower overall RT on the attention task. The interaction of a neurotransmission gene (CHRNA4) and a susceptibility gene (APOE) suggests that the efficiency of neuronal repair mechanisms may modulate the cholinergic system to influence attentional function.  相似文献   
64.
Tsang PS 《Acta psychologica》2006,121(2):137-175
This study contrasts the structural bottleneck and the resource view of attentional limits in time-sharing performance. The research incorporated features of the psychological refractory period (PRP) and the relative priority paradigm designed to maximize joint performance. A main distinction between the two attention views was their prediction on the extent that graded performance tradeoff was possible with graded priority changes. Detailed analysis of the performance and time-sharing strategies called into question the conclusions based exclusively on the PRP paradigm.  相似文献   
65.
This study examined the association between maternal smoking and exposure to environmental tobacco smoke (ETS) during pregnancy and infant heart rate. Participants were 62 mother-infant dyads where mother smoked during pregnancy, 47 dyads where mother did not smoke during pregnancy but was exposed to ETS and 47 dyads where mother did not smoke and was not exposed to ETS. Average heart rate (HR) and respiratory sinus arrhythmia (RSA) were assessed at 2-4 weeks of age during sleep. Infants in both exposure groups had higher HR and lower RSA than nonexposed infants. Furthermore, boys in both exposure groups had higher HR and lower RSA than girls. These results highlight the importance of considering prenatal ETS exposure and infant gender when assessing infant outcomes.  相似文献   
66.
The Classification of Violence Risk (COVR) is an interactive software program designed to estimate the risk that a person hospitalized for mental disorder will be violent to others. The software leads the evaluator through a chart review and a brief interview with the patient. At the end of this interview, the software generates a report that contains a statistically valid estimate of the patient's violence risk-ranging from a 1% to a 76% likelihood of violence-including the confidence interval for that estimate, and a list of the risk factors that the program took into account to produce the estimate. In this article, the development of the COVR software is described and several issues that arise in its administration are discussed.  相似文献   
67.
68.
Native Americans have higher rates of alcohol use, frequency of use, and increased rates of fetal alcohol syndrome, compared with other ethnic groups (J. Hisnanick, 1992; P. A. May, 1996; J. M. Wallace et al., 2003). High prevalence rates of alcohol misuse among Native Americans must be understood in light of their unique history, which has resulted in trauma and exposure to many risk factors for problem alcohol use. Many risk factors have been identified in the general population; however, only some of these risk factors have been examined among Native American populations. The unique history and world view of Native Americans mean that, often, risk factors operate differently from the way they do in other populations. The authors discuss interventions and promising treatments.  相似文献   
69.
Preschoolers' theory-of-mind development follows a similar age trajectory across many cultures. To determine whether these similarities are related to similar underlying ontogenetic processes, we examined whether the relation between theory of mind and executive function commonly found among U.S. preschoolers is also present among Chinese preschoolers. Preschoolers from Beijing, China (N= 109), were administered theory-of-mind and executive-functioning tasks, and their performance was compared with that of a previously studied sample of U.S. preschoolers (N= 107). The Chinese preschoolers outperformed their U.S. counterparts on all measures of executive functioning, but were not similarly advanced in theory-of-mind reasoning. Nonetheless, individual differences in executive functioning predicted theory of mind for children in both cultures. Thus, the relation between executive functioning and theory of mind is robust across two disparate cultures. These findings shed light on why executive functioning is important for theory-of-mind development.  相似文献   
70.
In this study, eight statistical selection strategies were evaluated for selecting the parameterizations of log‐linear models used to model the distributions of psychometric tests. The selection strategies included significance tests based on four chi‐squared statistics (likelihood ratio, Pearson, Freeman–Tukey, and Cressie–Read) and four additional strategies (Akaike information criterion (AIC), Bayesian information criterion (BIC), consistent Akaike information criterion (CAIC), and a measure attributed to Goodman). The strategies were evaluated in simulations for different log‐linear models of univariate and bivariate test‐score distributions and two sample sizes. Results showed that all eight selection strategies were most accurate for the largest sample size considered. For univariate distributions, the AIC selection strategy was especially accurate for selecting the correct parameterization of a complex log‐linear model and the likelihood ratio chi‐squared selection strategy was the most accurate strategy for selecting the correct parameterization of a relatively simple log‐linear model. For bivariate distributions, the likelihood ratio chi‐squared, Freeman–Tukey chi‐squared, BIC, and CAIC selection strategies had similarly high selection accuracies.  相似文献   
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