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71.
72.
Much research on adolescent delinquency pivots on the notion of peer influence. The peer effect that is typically employed
emphasizes the transmission of behaviors and attitudes between adolescents who are directly linked. In this paper, we argue
that to rely solely on those direct social ties to capture peer influence oversimplifies the realities of adolescent society.
We use data from the National Longitudinal Study of Adolescent Health to show that indirect peer relations can exercise independent
influences on adolescent delinquency. Adolescents actively draw on the examples of friends of friends, and even more distal
peers, as they develop their repertoires of action and identity. We argue, however, that this behavior actually reflects adolescents’
ongoing struggle to impress their closest friends and to preserve their social circle. Indeed, the extent to which adolescents
are willing to model the behavior of indirect contacts seems to decline as that behavior becomes more dissimilar from that
of their close friends. Our findings dovetail with an account of the adolescent as a rational actor who struggles for social
acceptance in a complex peer environment which offers conflicting behavioral models.
相似文献
Danielle C. PayneEmail: |
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The labor force participation rates of men and women aged 62-79 have notably increased since the mid-1990s. The result is a dramatic increase in the share of total money income attributable to earnings. For persons aged 65-69, the earnings share of total income increased from 28 percent in 1980 to 42 percent in 2009. For this age group in the late 1980s and early 1990s, Social Security benefits and earnings were roughly equal shares of total money income (about 30 percent); the earnings share is now more than 12 percentage points larger. When we focus on aged persons who receive Social Security benefits, earnings shares have increased markedly throughout the 62-79 age range since the early 1990s. We show that for aged persons with labor market earnings, those earnings have a large effect on their relative position in the distribution of annual money income of older Americans. 相似文献
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In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and flowering plants. However, authorities are often confronted with very young specimens. The aim of our study was to evaluate when the chemotype of cannabis plantlets can be surely determined through analysis of eight major cannabinoids content during growth. Drug-type seedlings and cuttings were cultivated, sampled each week, and analyzed by high-performance liquid chromatography with diode array detection. The chemotype of clones was recognizable at any developmental stage because of high total Δ(9)-tetrahydrocannabinol (THC) concentrations even at the start of the cultivation. Conversely, right after germination seedlings contained a low total THC content, but it increased quickly with plant age up, allowing chemotype determination after 3 weeks. In conclusion, it is not necessary to wait for plants' flowering to identify drug-type cannabis generally cultivated in Europe. 相似文献
79.
Purpose
To assess differences in victimization risk between African American and white, non-Latino inmates, and to estimate race group differences in the correlates of victimization.Methods
Random samples totaling 2,403 African Americans and 3,150 whites were drawn from all state prisons in Ohio and Kentucky and all private prisons in Ohio (n = 46). Race-specific bi-level models of physical assaults and property thefts were estimated. Differences between race-specific models in the magnitude of regression coefficients for the same predictors and outcomes were compared.Results
The odds of victimization by physical assault and by theft were significantly higher among whites compared to African Americans. Race group differences in the magnitude of several inmate level effects (e.g., age, sex, education, family status, officer “legitimacy”, custody score, visitation) were also significant, yet facility effects were similar for both groups.Conclusions
Assessing differences in the victimization experiences of African American and white inmates is important for developing effective crime prevention strategies in prison. We examined the most comprehensive models of inmate victimization (including inmate socio-demographics, activities during confinement, perceptions of officers, facility characteristics, and officer perceptions of rule enforcement) for one of the largest samples of prisons to date. 相似文献80.
Vacuum metal deposition (VMD) has been previously demonstrated as an effective development technique for latent fingermarks and in some cases has been shown to enhance prints developed with cyanoacrylate (CA) (superglue) fuming. This work utilizes scanning electron microscopy (SEM) to investigate the interactions of the two development techniques when applied to latent fingermarks on low-density polyethylene. CA is shown to act principally on the eccrine deposits around sweat pores, where polymerization results in long polymer fibrils a few 100 nm in width. Subsequent VMD processing results in additional areas of development, for example, between pores. However, the primary mode of deposition of zinc is by interaction with the polymerized CA, the fibrils of which become decorated with zinc nanoparticles. Areas with limited CA deposition and no significant polymerization are also enhanced with the VMD process, resulting in increased print development. 相似文献