Star formation and spiral structure in M81

High resolution digitized images of M81 in the radio continuum, H alpha, H I, and I band are used to see how well various density wave models agree in detail with observations. It was found that the observed width of the nonthermal radio arms favors a cloudy version of a density wave model. The radial distribution of the set of giant radio H II regions disagrees with the simple expression of Shu and Visser for star formation by a density wave. The observed displacements of the giant radio H II regions from the spiral velocity shock indicate that some revisions in the details of the ballistic particle model of Leisawitz and Bash are necessary

Modeling the Electromagnetic Radiation from Electrically Small Table-Top Products

It is noted that the most difficult radiated electromagnetic interference (EMI) problems with table-top products often occur at frequencies where the maximum dimensions of the product are much smaller than a wavelength. Electrically small table-top products tend to be much more efficient radiation sources than dipole source models would predict, and the radiation is generally much more difficult to contain than other types of EMI source models indicated. The ways in which electrically small sources radiate are investigated, and a technique for modeling electrically small table-top products that have power or signal cables is proposed. The end-driven wire model is a strategy for reducing the product to a form that is more readily analyzed. The results is a relatively simple configuration that includes only those parameters of the product that are of primary importance to the radiated EMI calculation

Mickey Donohue

https://digitalcommons.library.umaine.edu/mmb-vp/4533/thumbnail.jp

Distinguishing Between Animates And Inanimates: Not By Motion Alone

Martin E. P. Seligman, professor of psychology at the University of Pennsylvania, is one of the world\u27s leading authorities on learned helplessness and its relation to optimism and hope. This collection brings together eminent psychologists and professionals whose work has been greatly influenced by Seligman\u27s innovative work

A Lung Cancer Screening Personalized Decision-aid Improves Knowledge and Reduces Decisional Conflict Among a Diverse Population of Smokers at an Urban Academic Medical Center

Introduction: Few lung cancer screening decision aids have been tested in diverse populations. The study objective was to determine whether the online decision aid www.shouldiscreen.com impacts knowledge of and decisional conflict around lung cancer screening in a diverse population. Methods: Eligible patients had significant smoking histories, were at increased risk for lung cancer (ages 45-80, \u3e20 pack-years, smoking within last 15 years) and had no history of prior lung cancer or screening. Data was collected and analyzed in 2017. Results: 40 patients were enrolled: 80% were female, 62.5% black, 33% white, and 48% had a high school education or less. 80% were current smokers with a mean of 34 pack-years accumulated. 35% were eligible for screening by U.S. Preventive Services Task Force criteria. After reviewing the decision aid, knowledge increased in all categories including risk factors for lung cancer (3.58 to 4.30, p\u3c0.01), benefits of screening (1.58 to 2.30, p\u3c0.01), possible harms of screening (0.93 to 2.08, p\u3c0.01), and eligibility for screening (2.10 to 2.65, p\u3c0.01). Decisional conflict was reduced from 21.25 to 8.65 (p\u3c0.01). After use of the decision aid, more patients expressed a preference not to be screened for lung cancer, such that concordance with USPSTF guidelines decreased among those who were eligible to screen increased among those who did not yet meet eligibility criteria; however, this finding was not statistically significant. Conclusions: Even brief, unguided use of this web-based tool improved knowledge and reduced decisional conflict for a diverse group of smokers considering lung cancer screening

The impact of eliminating primary school tuition fees on child marriage in sub-Saharan Africa:A quasi-experimental evaluation of policy changes in 8 countries

BACKGROUND:Child marriage harms girls' health and hinders progress toward development goals. Randomized studies have shown that providing financial incentives for girls' education can effectively delay marriage, but larger-scale interventions are needed in light of slow progress toward curbing the practice. Many sub-Saharan African countries eliminated primary school tuition fees over the past two decades, resulting in massive increases in enrolment. We measured the effect of these policies on the probability of primary school completion and of marriage before 15 and 18 years of age. METHODS:We used Demographic and Health Surveys to assemble a dataset of women born between 1970 and 2000 in 16 countries. These data were merged with longitudinal information on the timing of tuition fee elimination in each country. We estimated the impact of fee removal using fixed effects regression to compare changes in the prevalence of child marriage over time between women who were exposed to tuition-free primary schooling and those who were not. RESULTS:The removal of tuition fees led to modest average declines in the prevalence of child marriage across all of the treated countries. However, there was substantial heterogeneity between countries. The prevalence of child marriage declined by 10-15 percentage points in Ethiopia and Rwanda following tuition elimination but we found no evidence that the removal of tuition fees had an impact on child marriage rates in Cameroon or Malawi. Reductions in child marriage were not consistently accompanied by increases in the probability of primary school completion. CONCLUSIONS:Eliminating tuition fees led to reductions in child marriage on a national scale in most countries despite challenges with implementation. Improving the quality of the education available may strengthen these effects and bolster progress toward numerous other public health goals

Epidemiologic analysis of racial/ethnic disparities: A rejoinder to Frank and Exner

http://dx.doi.org/10.1016/j.socscimed.2007.11.04

Sex hormone-binding globulin regulation of androgen bioactivity in vivo : validation of the free hormone hypothesis

Sex hormone-binding globulin (SHBG) is the high-affinity binding protein for androgens and estrogens. According to the free hormone hypothesis, SHBG modulates the bioactivity of sex steroids by limiting their diffusion into target tissues. Still, the in vivo physiological role of circulating SHBG remains unclear, especially since mice and rats lack circulating SHBG post-natally. To test the free hormone hypothesis in vivo, we examined total and free sex steroid concentrations and bioactivity on target organs in mice expressing a human SHBG transgene. SHBG increased total androgen and estrogen concentrations via hypothalamic-pituitary feedback regulation and prolonged ligand half-life. Despite markedly raised total sex steroid concentrations, free testosterone was unaffected while sex steroid bioactivity on male and female reproductive organs was attenuated. This occurred via a liganddependent, genotype-independent mechanism according to in vitro seminal vesicle organ cultures. These results provide compelling support for the determination of free or bioavailable sex steroid concentrations in medicine, and clarify important comparative differences between translational mouse models and human endocrinology

Serum Dioxin-like Activity Is Associated with Reproductive Parameters in Young Men from the General Flemish Population

BACKGROUND: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and some related environmental contaminants are aryl hydrocarbon receptor (AhR) ligands that exert reproductive and developmental toxicity in laboratory animals. In humans, fertility-related effects are less documented. OBJECTIVE: The aim of this study was to investigate the relationship between dioxin-like biological activity in serum and parameters of reproductive status in men from the general population 5 months after a polychlorinated biphenyl and dioxin food-contamination episode in Belgium. DESIGN: In the framework of the cross-sectional Flemish Environment and Health Study (FLEHS), we recruited 101 men 20–40 years of age and evaluated sperm parameters, measured sex hormones, and gathered information on a number of lifestyle factors. In addition, we determined the AhR-mediated enzymatic response elicited by individual serum samples and expressed it as TCDD equivalent concentrations (CALUX-TEQs) using an established transactivation assay. RESULTS: Age (p = 0.04) and the frequency of fish (p = 0.02) and egg (p = 0.001) consumption were independent positive determinants of serum dioxin-like activity. After correcting for possible confounders, we found that a 2-fold increase in CALUX-TEQ > 16 pg/L was associated with a 7.1% and 6.8% (both p = 0.04) decrease in total and free testosterone, respectively. We also observed a more pronounced drop in semen volume of 16.0% (p = 0.03), whereas sperm concentration rose by 25.2% (p = 0.07). No relationship was found with total sperm count or sperm morphology. CONCLUSIONS: These data suggest an interaction of dioxin-like compounds with the secretory function of the seminal vesicles or prostate, possibly indirectly through an effect on testosterone secretion, at levels not affecting spermatogenesis as such