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Background: Autoantibodies are of growing interest in cancer research as potential biomarkers; yet, the determinants of autoimmunity are not well understood. Antinuclear antibodies (ANA) are common in the general population and are more prevalent in women and older adults. Here, we examined the relationship of ANA with reproductive and hormonal factors in a representative sample of U.S. women. Methods: We analyzed data on reproductive history and exogenous hormone use in relation to serum ANA in 2,037 females ages 12 years and older from the National Health and Nutrition Examination Survey (NHANES; 1999–2004). Estimated ANA prevalences were adjusted for sampling weights. Prevalence ORs (POR) and 95% confidence intervals (CI) were adjusted for age, race, and poverty–income ratio, and models were stratified by menopause status. Results: In premenopausal women ages 20 years and older, ANA prevalence was associated with parity (P < 0.001; parous vs. nulliparous POR = 2.0; 95% CI, 1.2–3.4), but in parous women, ANA did not vary by number of births, age at first birth, years since last birth, or breastfeeding. In postmenopausal women, ANA prevalence was associated with an older age at menarche (P = 0.019; age 16–20 vs. 10–12 years POR = 3.0; 95% CI, 1.6–5.9), but not with parity. Oral contraceptives and estrogen therapy were not associated with a higher ANA prevalence. Conclusions: Childbearing (having had one or more births) may explain age-associated elevations in ANA prevalence seen in premenopausal women. Impact: These findings highlight the importance of considering reproductive history in studies of autoimmunity and cancer in women. Cancer Epidemiol Biomarkers Prev; 23(11); 2492–502. ©2014 AACR.

The problemof estimating parameters of amultivariate normal p-dimensional random vector is considered for a banded covariance structure reflecting mdependence. A simple non-iterative estimation procedure is suggested which gives an explicit, unbiased and consistent estimator of the mean and an explicit and consistent estimator of the covariance matrix for arbitrary p and m. Preliminary version published as Research Report 2008:3 at the Centre of Biostochastics Swedish University of Agricultural Sciences.The original publication is available at www.springerlink.com:Martin Ohlson, Zhanna Andrushchenko and Dietrich von Rosen, Explicit Estimators under m-Dependence for a Multivariate Normal Distribution, 2011, Annals of the Institute of Statistical Mathematics, (63), 1, 29-42.http://dx.doi.org/10.1007/s10463-008-0213-1Copyright: Springer Science Business Mediahttp://www.springerlink.com/

The properties of streamers and zonal magnetic structures in magnetic electron drift mode turbulence are investigated. The stability of such large scale structures is investigated in the kinetic and the hydrodynamic regime, for which an instability criterion similar to the Lighthill criterion for modulational instability is found. Furthermore, these large scale flows can undergo further nonlinear evolution after initial linear growth, which can lead to the formation of long-lived coherent structures consisting of self-bound wave packets between the surfaces of two different flow velocities with an expected modification of the anomalous electron transport properties.

The nonlinear dynamics of magnetic electron drift mode turbulence are outlined and the generation of large-scale magnetic structures in a non-uniform magnetized plasma by turbulent Reynolds stress is demonstrated. The loop-back of large-scale flows on the microturbulence is elucidated and the modulation of the electron drift mode turbulence spectrum in a medium with slowly varying parameters is presented. The wave kinetic equation in the presence of large-scale flows is derived and it can be seen that the small-scale turbulence and the large-scale structures form a self-regulating system. Finally, it is shown by the use of quasilinear theory that the shearing of microturbulence by the flows can be described by a diffusion equation in k-space and the corresponding diffusion coefficients are calculated.