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BackgroundPerfluoroalkyl substances (PFASs), including perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorohexane sulfonic acid (PFHxS), and perfluorononanoic acid (PFNA), are detectable in the serum of 95% of the U.S. population.ObjectiveConsidering the role of PFASs as endocrine disruptors, we examined their relationships with bone health.MethodsThe association between serum PFAS concentration and bone mineral density at total femur (TFBMD), femoral neck (FNBMD), lumbar spine (LSBMD), and physician-diagnosed osteoporosis was assessed in 1,914 participants using data from the National Health and Nutritional Examination Survey 2009–2010.ResultsThe mean age of the participants was 43 years. Men had higher serum PFAS concentrations than women (p < 0.001) except for PFNA. In both sexes, serum PFOS concentrations were inversely associated with FNBMD (p < 0.05). In women, significant negative associations were observed for natural log (ln)–transformed PFOS exposure with TFBMD and FNBMD, and for ln-transformed PFOA exposure with TFBMD (p < 0.05). In postmenopausal women, serum PFOS was negatively associated with TFBMD and FNBMD, and PFNA was negatively associated with TFBMD, FNBMD, and LSBMD (all p < 0.05). With one log unit increase in serum PFOA, PFHxS, and PFNA, osteoporosis prevalence in women increased as follows: [adjusted odds ratios (aORs)] 1.84 (95% CI: 1.17, 2.905), 1.64 (95% CI: 1.14, 2.38), and 1.45 (95% CI: 1.02, 2.05), respectively. In women, the prevalence of osteoporosis was significantly higher in the highest versus the lowest quartiles of PFOA, PFHxS, and PFNA, with aORs of 2.59 (95% CI: 1.01, 6.67), 13.20 (95% CI: 2.72, 64.15), and 3.23 (95% CI: 1.44, 7.21), respectively, based on 77 cases in the study sample.ConclusionIn a representative sample of the U.S. adult population, serum PFAS concentrations were associated with lower bone mineral density, which varied according to the specific PFAS and bone site assessed. Most associations were limited to women. Osteoporosis in women was also associated with PFAS exposure, based on a small number of cases.CitationKhalil N, Chen A, Lee M, Czerwinski SA, Ebert JR, DeWitt JC, Kannan K. 2016. Association of perfluoroalkyl substances, bone mineral density, and osteoporosis in the U.S. population in NHANES 2009–2010. Environ Health Perspect 124:81–87; http://dx.doi.org/10.1289/ehp.1307909

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The current state of physician leadership education consists mainly of executive degree programs designed for midcareer physicians. In 2004, the authors proposed that, by educating medical students in physician leadership and integrating this with a business management or public health degree program, graduates, health care organizations, and communities would benefit sooner. Given the lack of program models to guide program integration and development, the authors began a one-year inquiry to build a model leadership curriculum and integrate leadership education across degree programs. The qualitative inquiry resulted in several linked tasks. First, the authors identified a feasible method for concurrently delivering all three program components (MD degree, Leadership Curriculum, and MBA or MPH degree) during a five-year plan. Second, the authors chose a competency-based educational framework for leadership and then identified, adapted, and validated existing leadership competencies to their context. Third, the authors performed an extensive program alignment to identify existing overlaps and opportunities for integration within and across program components. Fourth, the authors performed a needs analysis to identify educational gaps, subsequently leading to redesigning two courses and to designing three new courses. A description of the Leadership Curriculum is also provided. This inquiry has led to the development of the Boonshoft Physician Leadership Development Program, which provides physician leadership education integrated with medical education and education in business management or public heath. Future program initiatives include developing leadership student assessment tools and testing the link between program activities and short- and long-term outcome measures of program success.

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Vitamin D deficiency is prevalent in obese American children. There was evidence that some cardiometabolic risk factors including lipid levels and oxidized LDL levels were significantly inversely associated with 25(OH)D concentration in our sample. Am. J. Hum. Biol. 28:736-742, 2016. © 2016 Wiley Periodicals, Inc.

The numerical calibration of the base of the Devonian is poorly constrained due to several factors. Few precise radioisotopic age determinations are available from the late Silurian and Early Devonian, and the limited published data carry large error bars from older analytical methodologies. Volcanic ashfalls suitable for dating occur in the Lower Devonian of the Appalachian Basin, but have not been precisely correlated into the global chronostratigraphical scheme because of limited bio‐ and lithostratigraphical information. Here, we report a new U‐Pb zircon radioisotopic age determination of 417.61 ± 0.12(0.23)[0.50] Ma and improved chronostratigraphical context, including revised biostratigraphy, for an ash bed in the New Scotland Formation, Helderberg Group, from the Lochkovian Stage that was previously identified as the Kalkberg K‐bentonite. This new information helps to integrate the classic New York Appalachian Basin succession into global Siluro‐Devonian stratigraphy, refine the calibration of the Silurian–Devonian boundary and more precisely estimate the duration of both time periods.