U.S. Fertility in Life Course Context: A Research Note on Using Census-Held Linked Administrative Records for Geographic and Sociodemographic Subgroup Estimation.

Fertility is a life course process that is strongly shaped by geographic and sociodemographic subgroup contexts. In the United States, scholars face a choice: they can situate fertility in a life course perspective using panel data, which is typically representative only at the national level; or they can attend to subnational contexts using rate schedules, which do not include information on life course statuses. The method and data source we introduce here, Census-Held Linked Administrative Records for Fertility Estimation (CLAR-FE), permits both. It derives fertility histories and rate schedules from U.S. Census Bureau-held data for the nation and by state, racial and ethnic subgroups, and the important life course status of parity. We generate three types of rates for 2000-2020 at the national and state levels by race and ethnicity: age-specific rates and both unconditional and conditional parity- and age-specific rates. Where possible, we compare these rates with those produced by the National Center for Health Statistics. Our new rate schedules illuminate state and racial and ethnic differences in transitions to parenthood, providing evidence of the important subgroup heterogeneity that characterizes the United States. CLAR-FE covers nearly the entire U.S. population and is available to researchers on approved projects through the Census Bureau's Federal Statistical Research Data Centers.

Competing Effects on the Average Age of Infant Death.

In recent decades, the relationship between the average length of life for those who die in the first year of life-the life table quantity a10-and the level of infant mortality, on which its calculation is often based, has broken down. The very low levels of infant mortality in the developed world correspond to a range of a10 quantities. We illustrate the competing effect of falling mortality and reduction in preterm births on a10 through two populations with very different levels of premature birth-infants born to non-Hispanic White mothers and infants born to non-Hispanic Black mothers in the United States-using linked birth and infant death cohort data. Through simulation, we further demonstrate that falling mortality reduces a10, while a reduction in premature births increases it. We use these observations to motivate the formulation of a new approximation formula for a10 in low-mortality contexts, which aims to incorporate differences in preterm birth through a proxy measure-the ratio of infant to under-five mortality. Models are built and tested using data from the Human Mortality Database. Model results and validation show that the newly proposed model outperforms existing alternatives.

Socioenvironmental context of sexual trauma and well-being of women veterans.

The incidence of episodes of harassment and rape among military populations has only recently been examined. In the present study, a sample of 336 female veterans in a primary care setting was assessed. The incidences of lifetime sexual victimization, anxiety, depression, and impact of trauma for victims of specific trauma contexts are presented. Results of the study indicated that female veterans with a history of cumulative rape experiences and civilian rape experiences are more at risk for anxiety and depression than those with only a military experience of rape. No significant differences were found for impact of event scores for different contexts of rape, however. Reporting of trauma was not associated with psychological well-being for women veterans. The results highlight the role of the socioenvironmental context of abuse as an important variable to examine, especially in military populations.

Proton-gated channels in PC12 cells.

Acid-sensing ion channels (ASICs) are expressed in various sensory and central neurons. The functional role of these channels remains elusive. Complex subunit combinations and lack of specific blockers for native receptors are likely to contribute to the difficulty of resolving the function of ASICs. Finding a neuronal cell line, which expresses a single population of ASICs, should prove to be useful in delineating the function of individual ASICs. Using patch-clamp, Ca(2+)-imaging, and RT-PCR techniques, we have explored the existence of ASICs in PC12 cells, a clonal neuronal cell line. Fast drops of extracellular pH activated transient inward currents in PC12 cells with pH(0.5) at 6.0-6.2. The ASICs in PC12 cells were selective for Na(+) with significant Ca(2+) permeability. Currents in PC12 cells were blocked by the nonselective ASIC blocker amiloride. PcTX1, a specific homomeric ASIC1a blocker, also blocked the ASIC currents with an IC(50) of approximately 1.5 nM. RT-PCR demonstrated the existence of ASIC1a transcript in both undifferentiated and nerve growth factor-differentiated PC12 cells. Our data suggest that PC12 cells likely contain a single population of functional proton-gated channel-homomeric ASIC1a. It might be an ideal neuronal cell line for the study of physiological and potential pathological roles of this key subunit of ASICs.