Sociocultural Determinants of Teenage Childbearing Among Latinas in California

Objectives U.S. Latinas have a persistently high rate of teenage childbearing, which is associated with adverse outcomes for both mother and child. This study was designed to investigate the roles of socioeconomic factors and acculturation in teenage childbearing in this population. Methods Logistic regression was used to analyze the association of measures of acculturation (language spoken at home, nativity, and age at immigration) and respondents’ parents’ education with age at first birth in a stratified sample of post-partum women in California. Results The unadjusted odds ratio for teenage birth for Latinas versus non-Latina Whites was 5.2 (95% CI 4.1–6.6). Nativity was not significantly associated with teen birth, but speaking Spanish at home was positively associated and immigrating at a later age was negatively associated with teen birth. Overall, these measures of acculturation accounted for 17% (95% CI 8–28%) of the difference in odds of teen birth between Latinas and non-Latina Whites. Higher levels of education among respondents’ parents had differentially protective effects across the racial/ethnic groups. Controlling for disparities in respondents’ parents’ education without changing its differential effects across racial/ethnic groups reduced the odds ratio for Latinas compared to non-Latina Whites by 30% (95% CI 14–60%). Conclusion These findings call into question common assumptions about the protective effect of acculturation on teen fertility and suggest that improving childhood socioeconomic factors among Latinas may decrease teen childbearing

Fundamentals of Forensic Anthropology

xiii.176 hal.;ind.;23 c

Stretching DNA Molecules in Strongly Confining Nanofluidic Slits

We experimentally investigate the stretching and relaxation of individual double-stranded DNA molecules in nanofluidic slits with depths that span the regime between moderate and strong confinement. DNA molecules are stretched by the application of a quadrupole-like homogeneous elongational electric field. In a moderately confining slit we verify the previously observed existence of two distinct relaxation times resulting from the transition from a bulk-like entropic spring force to one that is confinement dependent. In a strongly confining slit with a depth equal to one persistence length we observe the return to a coil–stretch transition that is governed by a single strain rate related to the confined spring constant. By measuring the equilibrium extension as a function of the applied strain rate as well as the relaxation dynamics from a highly stretched initial state, we are able to infer a hydrodynamic friction coefficient in the moderately and strongly confining slits that is in good agreement for a long DNA molecule. Our results are helpful for informing theoretical models of the force–extension relation for semiflexible polymers in quasi-two-dimensional space

Morphometric criteria for sexing juvenile human skeletons using the ilium

Previous attempts to sex juvenile skeletons have focused on the application of qualitative or semi-quantitative techniques. This study applies a variety of geometric morphometric methods, including eigenshape analysis, to this problem. Six metric criteria for the ilia were tested with the aim of investigating previous ideas concerning sexually diagnostic characters. This study uses 25 ilia from juveniles of known age and sex from Christ Church, Spitalfields, London. Ninety-six percent of juvenile ilia were correctly identified as male or female using the shape of the greater sciatic notch. Identification accuracy is shown to improve with age for several criteria. Males were identified to a higher accuracy than females. Application of geometric techniques improves the understanding of the relationship between age, sex, and shape and the clarity with which these relationships can be quantified. Archaeological and forensic relevance of the results are discussed with recommendations for future applicatio