3,505 research outputs found
An averaging principle for diffusions in foliated spaces
Consider an SDE on a foliated manifold whose trajectories lay on compact
leaves. We investigate the effective behavior of a small transversal
perturbation of order . An average principle is shown to hold such
that the component transversal to the leaves converges to the solution of a
deterministic ODE, according to the average of the perturbing vector field with
respect to invariant measures on the leaves, as goes to zero. An
estimate of the rate of convergence is given. These results generalize the
geometrical scope of previous approaches, including completely integrable
stochastic Hamiltonian system.Comment: Published at http://dx.doi.org/10.1214/14-AOP982 in the Annals of
Probability (http://www.imstat.org/aop/) by the Institute of Mathematical
Statistics (http://www.imstat.org
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SUBSTANCE USE COUNSELORS\u27 PERCEPTIONS OF EFFECTIVE TREATMENT MODALITIES FOR WOMEN WITH CHILDREN
The U.S Department of Health and Human Services (HHS) conducted a study and determined that approximately one-third to two-thirds of child neglect cases had some form of substance abuse related to the case. Further, it is reported that women who use alcohol or drugs are two times more likely to lose custody of their children than non- using mothers. The purpose of this study is to examine which treatment modalities substance use counselors find most effective when treating women with children. This study utilized a qualitative design asking eight open ended questions to fourteen substance use counselors employed at Prototypes in Pomona, CA. The substance use counselors were asked questions regarding what treatments they offered at their facility, what they believed the most effective treatment modalities are when treating women with children, and what barriers they faced when treating women with children.
Findings from this study found the holistic and client centered approaches to be the most effective treatment modalities when treating women with children. The holistic approach considers every aspect of the clientâs life and the client centered approach allows the counselors to develop care plans that are specific to their clientâs unique needs. Social workers should strive to keep women with their children while they are in treatment. Further research is needed to gain a better understanding of this population and to provide appropriate treatment, services, and resources to women and their children
Acesso aberto a informação cientĂfica agropecuĂĄria na internet: caso do sistema aberto e integrado de informação em agricultura (Sabiia).
RESUMO: Este trabalho apresenta o Sistema Aberto e Integrado de Informação em Agricultura (Sabiia) como mecanismo de busca automatizado que coleta e centraliza metadados de provedores de dados OAI-PMH cientĂficos de acesso aberto, previamente selecionados. O sistema reĂșne informaçÔes sobre agricultura e ĂĄreas afins, possibilitando o acesso ao texto integral (livros, capĂtulos de livros, artigos em periĂłdicos, folhetos, teses, anais e proceedings de eventos, entre outros) de milhares de publicaçÔes cientĂficas disponĂveis em diversas instituiçÔes nacionais e internacionais.SBIAgro 2011
Observational and genetic associations between cardiorespiratory fitness and cancer: a UK Biobank and international consortia study
Background
The association of fitness with cancer risk is not clear.
Methods
We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of lung, colorectal, endometrial, breast, and prostate cancer in a subset of UK Biobank participants who completed a submaximal fitness test in 2009-12 (Nâ=â72,572). We also investigated relationships using two-sample Mendelian randomisation (MR), odds ratios (ORs) were estimated using the inverse-variance weighted method.
Results
After a median of 11 years of follow-up, 4290 cancers of interest were diagnosed. A 3.5âml O2â
minâ1â
kgâ1 total-body mass increase in fitness (equivalent to 1 metabolic equivalent of task (MET), approximately 0.5 standard deviation (SD)) was associated with lower risks of endometrial (HRâ=â0.81, 95% CI: 0.73â0.89), colorectal (0.94, 0.90â0.99), and breast cancer (0.96, 0.92â0.99). In MR analyses, a 0.5âSD increase in genetically predicted O2â
minâ1â
kgâ1 fat-free mass was associated with a lower risk of breast cancer (ORâ=â0.92, 95% CI: 0.86â0.98). After adjusting for adiposity, both the observational and genetic associations were attenuated.
Discussion
Higher fitness levels may reduce risks of endometrial, colorectal, and breast cancer, though relationships with adiposity are complex and may mediate these relationships. Increasing fitness, including via changes in body composition, may be an effective strategy for cancer prevention
Exact Histogram Specification Optimized for Structural Similarity
An exact histogram specification (EHS) method modifies its input image to
have a specified histogram. Applications of EHS include image (contrast)
enhancement (e.g., by histogram equalization) and histogram watermarking.
Performing EHS on an image, however, reduces its visual quality. Starting from
the output of a generic EHS method, we maximize the structural similarity index
(SSIM) between the original image (before EHS) and the result of EHS
iteratively. Essential in this process is the computationally simple and
accurate formula we derive for SSIM gradient. As it is based on gradient
ascent, the proposed EHS always converges. Experimental results confirm that
while obtaining the histogram exactly as specified, the proposed method
invariably outperforms the existing methods in terms of visual quality of the
result. The computational complexity of the proposed method is shown to be of
the same order as that of the existing methods.
Index terms: histogram modification, histogram equalization, optimization for
perceptual visual quality, structural similarity gradient ascent, histogram
watermarking, contrast enhancement
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