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201.
Sipping alcohol during childhood may be a marker of differentiation as regards children’s future risk of underage drinking; yet very little is known about alcohol use when it occurs among elementary school-aged children. The purpose of the present study is to examine alcohol sipping behavior in a sample of third-grade school children to learn whether sipping is associated with attributes that could increase children’s likelihood of further underage drinking. We collected telephone interview data from 1,050 mothers and their third grade children (mean age 9.2 years; 48.2 % male) residing in the Southeastern United States. The majority of mothers were White non-Hispanic (69.02 %) or Black non-Hispanic (21.3 %); most (85 %) lived in households shared with fathers or other adult caretakers. We hypothesized that children who sip alcohol would score lower than abstinent peers on indicators of competence and score higher on indicators of exposure to alcohol-specific socialization by parents and peers. A multivariate model controlling for frequency of parent alcohol use and demographic covariates showed that children who had sipped alcohol were significantly less likely than abstinent peers to affirm indicators of competence and significantly more likely to affirm indicators of exposure to alcohol specific socialization by parents and by same age peers. These preliminary findings suggest that developmental attributes associated with risk of underage drinking begin to differentiate at least as young as middle childhood. Research is needed to test prospectively for continuity between alcohol risk attributes present in middle childhood and future alcohol use.  相似文献   
202.
The peer context is a central focus in research on adolescent risk behaviors but few studies have investigated the role of the peer context in the perpetration of adolescent dating violence. This longitudinal study examined between-subjects and within-person contemporaneous and lagged effects of peer attributes, measured with social network analyses, on trajectories of dating violence perpetration and determined if effects varied by grade and/or sex of the adolescent. Data are from adolescents who participated in a five-wave panel study beginning when they were in 7 through 9th grade and ending when they were in 10 through 12th grade (n = 3,412); half were male, 40.5 % were white, 49.9 % were black and 10.4 % were of another race/ethnicity. Significant between-subjects effects indicate that adolescents who typically have friends who use dating violence, and girls who are typically high in social status, are at increased risk for using dating violence throughout adolescence. Adolescents who typically have high quality friendships and girls who typically have friends with pro-social beliefs are at decreased risk for using dating violence throughout adolescence. Significant within-person contemporaneous effects indicate that both boys and girls reported lower levels of dating violence than usual at times when they had more friends with pro-social beliefs, and reported higher levels of dating violence than usual at times when they had higher social status. None of the lagged effects were significant and none of the effects varied across grade. These findings suggest that the peer context plays an important role in the development of the perpetration of adolescent dating violence.  相似文献   
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204.
Milton J  Ferguson B  Mills T 《危机》1999,20(4):171-177
General practitioners (GPs) are assumed to occupy an important position in the prevention of suicide through the introduction of risk assessment techniques commonly used in psychiatric practice. Despite this theoretical role for primary care services, it remains unclear how frequently GPs implement risk assessment in patients who may be vulnerable to suicide. To address this, a retrospective survey of probable suicides was conducted within a primary care setting utilizing a questionnaire of GPs who had experienced a patient suicide and was augmented by hospital and coroners' records. 85% of questionnaires were returned and 61 deaths were adjudged as suicides during the year long census period. 75% of suicides were male and 54% were aged under 35.28% were in contact with psychiatric services prior to death, although 60% had some diagnosis of mental disorder. GPs had little knowledge of a patient's life circumstances in up to half of cases. Recording of risk assessment occurred in 38% of subjects, was positively associated with prior psychiatric contact (p = 0.001) but negatively associated with presence of physical illness (p = 0.004), older patient age (p = 0.04), and GPs length in practice (p = 0.05). One GP felt their suicide case was preventable. The low rate of risk assessment and limited knowledge of patient lifestyle point to the need for active engagement of GPs in future suicide prevention strategies and should influence the content of training programs in primary care.  相似文献   
205.
Studies are reported on microbial conversion of various unsaturated fatty acids to 10-hydroxy and/or 10-oxo fatty acids by Micrococcus luteus. Four fatty acids possessing cis-9-unsaturation produced 10-hydroxy and 10-oxo fatty acid products, but three enoic acids possessing trans-9-unsaturation or double bond(s) in other than the 9-carbon position were inactive as substrates. 10-Hydroxy palmitic and stearic acids were converted to the corresponding 10-oxo fatty acids, but the 10-oxo compounds were inactive as substrates. This indicates that the metabolic sequence of cis-9-enoic fatty acid by the microbial enzyme(s) is first converted to 10-hydroxy fatty acid and then to its 10-oxo compound.  相似文献   
206.
Comparison techniques used in bite mark analysis are many and varied, the choice of technique depending largely on personal preference. Until recently, no one technique has been shown to be better than the others, and very little research has been carried out to compare different methods. This study evaluates and compares the accuracy of direct comparisons between suspects' models and bite marks with indirect comparisons in the form of conventional traced overlays of suspects' models or a new method using photocopier-generated overlays. Artificial bite marks in pigskin were made using standardized sets of models and recorded as photographs and fingerprint powder lifts on tape. The bite mark photographs and fingerprint lifts were coded and randomized so that a blind comparison could be made with the models, traced overlays, and photocopier-generated overlays using a modified version of the American Board of Forensic Odontology Scoring (ABFO) System for Bite Marks. It was found that the photocopier-generated overlays were significantly more accurate at matching the correct bite mark to the correct models irrespective of whether the bite mark was recorded photographically or as a fingerprint lift. The photocopier-generated overlays were also found to be more sensitive at matching the correct bite marks to the correct models than the other two methods used. The modified ABFO scoring system was able to discriminate between a correct match and several incorrect matches by awarding a high score to the correct match.  相似文献   
207.
We studied the biomechanical behaviour of ring and strip specimens from along the length of 18 vertebral arteries taken from 16 subjects aged 28-90 years, in order to consider some of the factors which may play a role in vertebral artery rupture. The method was chosen to allow a comparison between circumferential distension (ring samples) and longitudinal extension, (strip samples). The samples were extended between the jaws of a tensile testing apparatus until the specimen broke and a number of biomechanical parameters were derived. These were the percentage extension to break, the tensile strength, Young's modulus and the peak load. There were a number of important findings. The vertebral artery was shown to be susceptible to longitudinal stretching with a number of strip samples breaking when extended by as little as 16-20%. The tensile strength and load at peak of the strip specimens were correspondingly lower than for the ring samples. Marked intersubject variations were shown for all these parameters and prominent changes in behaviour occurred along the vertebral artery. This study indicates that the artery may be susceptible to head and neck movements which cause the vessel to stretch, and intersubject variations in behaviour may be one important explanation for the marked differences in outcome which appear to exist in subjects who suffer broadly similar head and neck insults.  相似文献   
208.
209.
Affluent Americans support more conservative economic policies than the nonaffluent, and government responds disproportionately to these views. Yet little is known about the emergence of these consequential views. We develop, test, and find support for a theory of class cultural norms: These preferences are partly traceable to socialization that occurs on predominantly affluent college campuses, especially those with norms of financial gain, and especially among socially embedded students. The economic views of the student's cohort also matter, in part independently of affluence. We use a large panel data set with a high response rate and more rigorous causal inference strategies than previous socialization studies. The affluent campus effect holds with matching, among students with limited school choice, and in a natural experiment; and it passes placebo tests. College socialization partly explains why affluent Americans support economically conservative policies.  相似文献   
210.
This report assesses the effects on peripheral oxygen saturation and heart rate that positional restraint induces when a person is prone, handcuffed, and "hog-tied." Peripheral oxygen saturation and heart rate were monitored at rest, during exercise, and during recovery from exercise for 10 adult subjects. The effects of positional restraint produced a mean recovery time that was significantly prolonged. Consequently, the physiological effects produced by positional restraint should be recognized in deaths where such measures are used.  相似文献   
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