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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.
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   
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