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41.
Although behavior genetic studies have suggested that early substance use is primarily environmentally mediated, no study has sought to identify the specific sources of environmental variance. Using data obtained from multiple informants, this study assessed the contributions of peer deviance and parent-child relationship problems to substance use in 14-year-old male and female twins (N = 1,403) drawn from the Minnesota Twin Family Study (MTFS). All three phenotypes were influenced primarily by shared environmental variance (average c(2) =.51), as was the overlap among them. Moreover, peer deviance and parent-child relationship problems accounted for approximately 77% of the variance in early substance use. Findings also indicated that peer deviance, but not parent-child relationship problems, accounted uniquely for variance in early substance use.  相似文献   
42.
In five experiments, we investigated the effects of voice congruency (same vs. different voices at study and at test) on remembering and knowing in recognition memory. With low- and medium-frequency three- or four-syllable words, a voice congruency effect occurred only in remembering. With nonwords, voice congruency effects occurred both in remembering and in knowing. With nonwords and divided attention at study, the voice congruency effect transferred almost completely from remembering to knowing. By showing a transfer of effects from remembering to knowing as encoding became more impoverished, these findings support a distinctiveness/fluency account of remembering and knowing as well as the theory that remembering and knowing indicate retrieval of events from episodic and semantic memory systems, respectively.  相似文献   
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This study evaluates a measurement model for Attention Deficit/Hyperactivity Disorder (ADHD). The DSM-IV divides 18 symptoms into two groups, inattentive and hyperactive/impulsive. Elementary school teachers rated 21,161 children in 4 locations: Spain, Germany, urban US, and suburban US. Confirmatory factor analysis suggested that the 2-factor model (inattention, hyperactivity/impulsivity) shows the best fit. A third factor, impulsivity, was too slight to stand-alone. Children with academic performance problems were distinguished by inattention, but children with behavior problems typically had elevations in inattention, hyperactivity, and impulsivity. Between-site differences were statistically significant, but so small that we conclude that same measurement model fits all 4 samples in 2 continents.  相似文献   
44.
Dilemmas in military medical ethics since 9/11   总被引:2,自引:0,他引:2  
The attack on the United States by terrorists on 9/11 and the war with Iraq have raised new ethical questions for the military and for military physicians (Herman 2002; Elshtain 2003). How and when attacks may occur now is less predictable. Planes have been hijacked, and persons dressed as civilians may carry bombs to blow themselves and others up. These dangers pose an increased threat, and, thus, there is a need for new defensive measures. How far these measures should go is, however, greatly open to debate. One of the most difficult ethical question raised for the military and military doctors by these developments is what interrogation methods are permissable when questioning captured terrorists. The licitness of different interrogation practices is, however, only one of the ethical problems potentially encountered by military physicians now having to treat terrorists and POWs. The following discussion presents the major concerns regarding this and other issues.  相似文献   
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Memory updating is the ability to select and update relevant information and suppress no-longer-relevant data. The few studies in this area, targeting mainly the verbal domain, have investigated and confirmed an age-related decline in working memory updating ability (De Beni & Palladino, 2004; Van der Linden, Bredart, & Beerten, 1994). The present research examines the ability of younger and older adults to update information in verbal and visuo-spatial running memory tasks. Results showed that the participants' performance was higher in the verbal than in the visuo-spatial task. Nonetheless, independently of the task domain, an age-related decline in updating performance was found. Moreover, analysis of serial positions suggested that, in the updating procedure, the participants were not attempting to actively maintain items, preferring to adopt a low-effort, "recency-based" strategy. The use of this type of strategy is more evident in older participants, as shown in both the accuracy performance and the proportion of intrusion errors.  相似文献   
49.
The current study examined gender differences in mothers' and fathers' internal state language (ISL), children's use of ISL, and whether ISL was related to parents' ratings of the children's social skills. Fifty‐seven (28 boys, 29 girls) toddler/preschool children (M age = 32.5 months, SD = 5.38 months) were observed separately with their mothers and fathers in their homes while they discussed pictures of children's facial expressions of emotions. Parents completed a questionnaire concerning their child's social–emotional behaviours (i.e. BASC‐2). Parents used more ISL with sons compared with daughters, and sons used more ISL with mothers than with fathers. No overall differences were found between mothers' and fathers' ISL. Children's social skills as rated by mothers were predicted by mothers' ISL comments, whereas children's social skills as rated by fathers were predicted by children's age and fathers' ISL clarifications. Implications and limitations of the study are discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
50.
This study assessed a new microswitch arrangement for eyelid responses using an optic sensor placed above the cheekbone and a small sticker on the person's eyelid. This new arrangement, which was designed to avoid interference of the microswitch with the person's visual functioning, was tested on three adults with acquired brain injury and multiple (consciousness, communication, and motor) disabilities. The study was carried out according to a non-concurrent multiple baseline design across participants. Data showed the new microswitch arrangement was suitable for all three participants, who increased their responding during the intervention phase of the study when their responses allowed them to access preferred stimulation. Practical implications of the findings are discussed.  相似文献   
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