62,717 research outputs found
The Relationship of Education and Acculturation with Vigorous Intensity Leisure Time Physical Activity by Gender in Latinos
Objectives: Latinos have poorer health outcomes among certain conditions (e.g. diabetes, obesity, mental health) compared to non-Latino Whites in the U.S., in part due to difference in the amount of physical activity, which are heavily influenced by sociocultural factors such as educational attainment and acculturation. Vigorous-intensity leisure time physical activity (VLTPA) may provide health benefits with a shorter amount of time than moderate-to-light physical activity. However, VLTPA has been significantly understudied compared to LTPA in general. The purpose of this study is to examine the associations between educational attainment, acculturation, and VLTPA by gender among Latino adults in the U.S. Design: Nationally representative samples of Latino adults aged 25 years and older (n = 4393) from the 2010 National Health Interview Survey were analyzed. VLTPA was measured as the number of hours per week of VLTPA consisting of heavy sweating or large increases in breathing and heart rate. Acculturation was measured as the degree to which the English language versus the Spanish language was spoken most often. The zero-inflated Poisson regression model was constructed using the full information maximum likelihood estimation and controlling for a series of sociodemographic characteristics and relevant health behaviors. Results: Educational attainment was positively associated with VLTPA among Latino adults [exp(b) = 1.09, p \u3c 0.05)]. Similarly, greater acculturation was associated with greater hours/week of VLTPA [exp(b) = 1.10, p \u3c 0.05)]. Lastly, the effect of educational attainment on VLTPA significantly varied by gender. Conclusions: Education had a positive association and acculturation had negative association with the hours/week of VLTPA among Latinos. Also, the association between education and VLTPA was significantly stronger among women than men. These findings inform culturally and socially sensitive approaches to improve the health of Latinos, in hopes to address health disparities by race/ethnicity the U.S
Hopfield Networks in Relevance and Redundancy Feature Selection Applied to Classification of Biomedical High-Resolution Micro-CT Images
We study filter–based feature selection methods for classification of biomedical images. For feature selection, we use two filters — a relevance filter which measures usefulness of individual features for target prediction, and a redundancy filter, which measures similarity between features. As selection method that combines relevance and redundancy we try out a Hopfield network. We experimentally compare selection methods, running unitary redundancy and relevance filters, against a greedy algorithm with redundancy thresholds [9], the min-redundancy max-relevance integration [8,23,36], and our Hopfield network selection. We conclude that on the whole, Hopfield selection was one of the most successful methods, outperforming min-redundancy max-relevance when\ud
more features are selected
Gauge field theory approach to spin transport in a 2D electron gas
We discuss the Pauli Hamiltonian including the spin-orbit interaction within
an U(1) x SU(2) gauge theory interpretation, where the gauge symmetry appears
to be broken. This interpretation offers new insight into the problem of spin
currents in the condensed matter environment, and can be extended to Rashba and
Dresselhaus spin-orbit interactions. We present a few outcomes of the present
formulation: i) it automatically leads to zero spin conductivity, in contrast
to predictions of Gauge symmetric treatments, ii) a topological quantization
condition leading to voltage quantization follows, and iii) spin
interferometers can be conceived in which, starting from a arbitrary incoming
unpolarized spinor, it is always possible to construct a perfect spin filtering
condition.Comment: Invited contribution to Statphys conference, June 2009, Lviv
(Ukraine
The exactly solvable spin Sutherland model of B_N type and its related spin chain
We compute the spectrum of the su(m) spin Sutherland model of B_N type,
including the exact degeneracy of all energy levels. By studying the large
coupling constant limit of this model and of its scalar counterpart, we
evaluate the partition function of their associated spin chain of
Haldane-Shastry type in closed form. With the help of the formula for the
partition function thus obtained we study the chain's spectrum, showing that it
cannot be obtained as a limiting case of its BC_N counterpart. The structure of
the partition function also suggests that the spectrum of the Haldane-Shastry
spin chain of B_N type is equivalent to that of a suitable vertex model, as is
the case for its A_{N-1} counterpart, and that the density of its eigenvalues
is normally distributed when the number of sites N tends to infinity. We
analyze this last conjecture numerically using again the explicit formula for
the partition function, and check its validity for several values of N and m.Comment: Typeset in LaTeX (24 pages, 4 figures). arXiv admin note: text
overlap with arXiv:0909.296
The spectrum of gravitational waves in an f(R) model with a bounce
We present an inflationary model preceded by a bounce in a metric
theory. In this model, modified gravity affects only the early stages of the
universe. We analyse the predicted spectrum of the gravitational waves in this
scenario using the method of the Bogoliubov coefficients. We show that there
are distinctive (oscillatory) signals on the spectrum for very low frequencies;
i.e., corresponding to modes that are currently entering the horizon.Comment: 4 pages, 2 figures. Contribution to the Spanish Relativity Meeting in
Portugal 2012 (ERE2012), Guimaraes, Portuga
- …