Iranian STR variation at the fringes of biogeographical demarcation

The integrative relationship between population genetics and forensic biology allows for a thorough genetic characterization of extant human populations. This study aimed to genetically characterize 150 unrelated healthy donors from a general population in Iran both forensically and phylogenetically. The allelic frequencies of 15 STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818 and FGA) were generated. This constitutes the core of polymerase chain reaction (PCR)-based DNA genetic markers in the US Combined DNA Index System (CODIS) plus two additional loci (D2S1338 and D19S433) that together are consistent with several other worldwide database requirements. There were no deviations from Hardy-Weinberg expectations. Based upon the allelic frequencies, several important forensic parameters were calculated including: gene diversity (GD) index, power of discrimination (PD), polymorphic information content (PIC) and power of exclusion (PE). G-tests indicate the allelic frequencies of the Iranians are statistically non-significant compared to two Turkish populations yet, statistically different from the remaining 18 groups obtained from the literature and examined in this study. This suggests that the Iranian dataset may be forensically equivalent to the dataset from the Turkish region of Eastern Anatolia and the general population from Turkey. Phylogenetic analysis of our population with the full set of 15 loci indicate the Iranians occupy an intermediate position relative to the major Caucasian and East Asian clades on a global level. A regional phylogenetic analysis using 13 of the 15 loci indicate the Iranians segregate in a more compact association with groups from southeastern Spain, Arabs from Morocco and Syria, and especially with the general population from Turkey and those from Eastern Anatolia. These groups are flanked by highly differentiated populations from northern India and a Berber group from Tunisia on opposing ends of the regional phylogram. This report also demonstrates the necessity to thoroughly characterize the genetic composition of populations located in geographic intersections in order to choose the appropriate dataset on which to base forensic calculations, not only at an intra-population level, but also at an inter-population level as well.     

Twenty years of progress in addressing domestic violence: an agenda for the next 10

The past 20 years have seen great strides in addressing violence against women by their male partners. Although the author cannot point to one single intervention or set of interventions as being the most effective, institutional reforms that have included coordinated community responses have had a positive impact. During the next 10 years, researchers must learn how to address the obstacles that prevent institutional responses from being more effective in addressing the needs of victims.     

Reconsidering Peer Influences on Delinquency: Do Less Proximate Contacts Matter?

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.

The increasing labor force participation of older workers and its effect on the income of the aged

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.     

Evolution of the content of THC and other major cannabinoids in drug-type cannabis cuttings and seedlings during growth of plants

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.