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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.

A two-fields model that self-consistently describes the coupled, spectral dynamics of flute mode large-scale flows turbulence is presented. This model has a characteristic form of a 'predator–prey' system, in which the populations of flute mode quanta (prey), growing via linear instability, generate large-scale flows (predators) through Reynolds stress. Concurrently, the mean flow growth regulates the prey population. To understand the long term nonlinear evolution of this one-prey two-predator system, a low-dimensional prototype of the model was constructed, assuming that the dynamics of such a complex system can be described within a phenomenological zero-dimensional approach. It is shown in the frame of this model that the dynamic outcome of interactions between the three system components may lead, depending on the system parameters, to their coexistence in the form of oscillatory solutions corresponding to quasi-periodic bursting of turbulence intensity level. These solutions are consistent with the time dependent behaviour of flute mode turbulence recently observed in numerical simulations.

Nonlinear dynamics of the magnetic electron drift mode turbulence is outlined and generation of large-scale magnetic structures in a nonuniform unmagnetized plasma by turbulent Reynolds stress is demonstrated. A two-component turbulent system consisting of magnetic fluctuations and generated secondary flows is considered. The evolution equations for mean magnetic flow generation are obtained by averaging the two-field model equations over fast small scales. It is found, in turn, that the pattern of the flow modulates and regulates the turbulence dynamics. The main features of the flows are controlled by the structure of the nonlinear coupling to the small-scale magnetic fluctuations as well as by the spectral properties of the turbulence and its anisotropy. Thus, the parent waves and secondary magnetic flows form a self-regulating system. It is shown that the presence of large-scale structures leads to shearing of turbulence. The k-space diffusion coefficient for the magnetic zonal flows and streamers are...

Generation of large-scale flows (zonal flows and streamers) by flute mode turbulence is examined. The evolution equations for mean flow generation are obtained by averaging the model equations over fast small scales. For a system containing both drift-type waves and large-scale structures, small scales are modulated by larger scale shear flows so that energy in the small-scale component is not conserved. A WKB-type wave kinetic equation that describes the conservation (along the rays) of an action-like invariant of the flute mode turbulence with slowly varying parameters due to the mean sheared flow is formulated. The relevant action-like integral is shown to correspond to the quantity conserved for the small-scale component alone. The structure of the action integral is determined by the structure of the matrix element describing the interaction of the small-scale and large-scale component. The k-space diffusion coefficient for the zonal flows and streamers are calculated.

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/

We focus on Bayesian network (BN) classifiers and formalize the feature selection from a perspective of improving classification accuracy. To exploring the effect of high-dimensionality we apply the growing dimension asymptotics. We modify the weighted BN by introducing inclusion-exclusion factors which eliminate the features whose separation score do not exceed a given threshold. We establish the asymptotic optimal threshold and demonstrate that the proposed selection technique carries improvements over classification accuracy.

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 properties of zonal and streamer flows in the flute mode turbulence are investigated. The stability criteria and the frequency of these flows are determined in terms of the spectra of turbulent fluctuations. Furthermore, it is shown that zonal flows can undergo a further nonlinear evolution leading to the formation of long-lived coherent structures which consist of self-bound wave packets supporting stationary shear layers, and thus can be characterized as regions with a reduced level of anomalous transport.

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.