Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 132 )

2018 ( 207 )

2017 ( 224 )

2016 ( 286 )

Custom range...

Search Results: 1 - 10 of 153670 matches for " Nelson F Sanchez "
All listed articles are free for downloading (OA Articles)
Page 1 /153670
Display every page Item
Physical activity reduces risk for colon polyps in a multiethnic colorectal cancer screening population
Nelson F Sanchez, Bryan Stierman, Said Saab, Divya Mahajan, Howa Yeung, Fritz Francois
BMC Research Notes , 2012, DOI: 10.1186/1756-0500-5-312
Abstract: We enrolled 982 patients: 558 Hispanic, 202 Asian,149 Black, and 69 White. Patients who reported exercising one or more hours weekly had a lower prevalence of any polyps (25.3% vs 33.2%, P?=?0.008) as well as adenomas (13.8 vs. 18.9%, P?=?0.03) compared to those who did not exercise. Black and Hispanic patients and those who were overweight or obese also had lower prevalence of polyps if they led an active lifestyle. Multivariate analysis revealed that age >55, male sex, and Black race/ethnicity were positively associated with the presence of adenomas, while a history of exercising one hour or more weekly was an independent negative predictor for the presence of adenomas anywhere in the colon (OR 0.67; 95% CI 0.4 - 0.9, P?=?0.03).Exercising one hour per week was associated with a lower prevalence of polyps and adenomas when compared to those who exercised less or not at all. An active lifestyle provides benefits to groups who are at risk for colorectal cancer, such as Blacks. It also provides significant protection to overweight and obese individuals. Public health initiatives should promote physical activity as a cancer prevention tool in multiethnic populations.noneAs the second leading cause of overall cancer death in the United States, colorectal cancer (CRC) remains an important preventable public health concern. In 2010 an estimated 142,570 new cases of CRC were diagnosed and there were 51,370 associated deaths [1]. There are notable racial/ethnic differences in the epidemiology of the disease. The National Cancer Institute’s 2007 Surveillance Epidemiology and End Results (SEER) Report determined a colorectal cancer incidence rate of 54.71/100,000 for Blacks versus 43.16 for Whites, 39.78 for Asians, and 35.84 for Hispanics [2]. Identifying modifiable factors that influence the epidemiology of colorectal cancer incidence among multiethnic groups might be informative for the development of public health strategies targeting the disease.Physical activity has bee
Four-Year Treatment Outcomes of Adult Patients Enrolled in Mozambique's Rapidly Expanding Antiretroviral Therapy Program
Andrew F. Auld,Francisco Mbofana,Ray W. Shiraishi,Mauro Sanchez,Charity Alfredo,Lisa J. Nelson,Tedd Ellerbrock
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0018453
Abstract: In Mozambique during 2004–2007 numbers of adult patients (≥15 years old) enrolled on antiretroviral therapy (ART) increased about 16-fold, from <5,000 to 79,500. All ART patients were eligible for co-trimoxazole. ART program outcomes, and determinants of outcomes, have not yet been reported.
Incidence and Determinants of Tuberculosis among Adults Initiating Antiretroviral Therapy – Mozambique, 2004–2008
Andrew F. Auld, Francisco Mbofana, Ray W. Shiraishi, Charity Alfredo, Mauro Sanchez, Tedd V. Ellerbrock, Lisa J. Nelson
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0054665
Abstract: Background In Mozambique, tuberculosis (TB) is thought to be the most common cause of death among antiretroviral therapy (ART) enrollees. Monitoring proportions of enrollees screened for TB, and incidence and determinants of TB during ART can help clinicians and program managers identify program improvement opportunities. Methodology/Principal Findings We conducted a retrospective cohort study among a nationally representative sample of the 79,500 adults (>14 years old) initiating ART during 2004–2007 to estimate clinician compliance with TB screening guidelines, factors associated with active TB at ART initiation, and incidence and predictors of documented TB during ART follow-up. Of 94 sites enrolling >50 adults on ART, 30 were selected using probability-proportional-to-size sampling; 2,596 medical records at these sites were randomly selected for abstraction and analysis. At ART initiation, median age of patients was 34, 62% were female, median baseline CD4+ T-cell count was 153/μL, and 11% were taking TB treatment. Proportions of records with TB screening documentation before ART initiation improved from 31% to 66% during 2004–2007 (p<0.001). TB screening compliance varied widely by ART clinic [n = 30, 2%–98% (p<0.001)] and supporting non-Governmental Organization (NGO) [n = 7, 27%–83% (p<0.001)]. Receiving TB treatment at ART enrollment was associated with male sex (p<0.001), weight <45 kg (p<0.001) and CD4<50/μL (p = 0.001). Isoniazid preventive therapy (IPT) was prescribed to <1% of ART enrollees not taking TB treatment. TB incidence during ART was 2.32 cases per 100 person-years. Factors associated with TB incidence included adherence to ART <95% (AHR 2.06; 95% CI, 1.32–3.21). Conclusion Variations in TB screening by clinic and NGO may reflect differing investments in TB screening activities. Future scale-up should target under-performing clinics. Scale-up of TB screening at ART initiation, IPT, and ART adherence interventions could significantly reduce incident TB during ART.
The CALIFA survey: A panoramic view on galaxy properties
S. F. Sanchez
Physics , 2015,
Abstract: We present here a brief summary of the status of the on-going CALIFA survey. We have just started the last semester of observing (Spring 2015). So far, we have gathered IFU data of more than 600 galaxies, ~85% of them corresponding to the main CALIFA sample (516 objects). We give an overview of some of the main science results that have been published by the CALIFA team during the last four years. In particular, we emphasise the results regarding the properties of the ionized gas in galaxies and the gradients in oxygen abundance, as well as the evidence for inside-out growth of galaxies uncovered through analysis of the stellar population content.
Quantum fields in anti-de Sitter space and the Maldacena conjecture
Braga, Nelson R. F.;
Brazilian Journal of Physics , 2002, DOI: 10.1590/S0103-97332002000500010
Abstract: we review the relation between the maldacena conjecture, also known as ads=cft correspondence, and the so-called holographic principle that seems to be an essential ingredient for a quantum gravity theory. we also illustrate the idea of holography by showing that the curvature of the anti-de sitter space reduces the number of degrees of freedom making it possible to find a mapping between a quantum theory defined on the bulk and another defined on the corresponding boundary.
Quantum fields in anti-de Sitter space and the Maldacena conjecture
Braga Nelson R. F.
Brazilian Journal of Physics , 2002,
Abstract: We review the relation between the Maldacena conjecture, also known as AdS=CFT correspondence, and the so-called holographic principle that seems to be an essential ingredient for a quantum gravity theory. We also illustrate the idea of holography by showing that the curvature of the anti-de Sitter space reduces the number of degrees of freedom making it possible to find a mapping between a quantum theory defined on the bulk and another defined on the corresponding boundary.
BRST quantization of anomalous gauge theories
Nelson R. F. Braga
Physics , 1994, DOI: 10.1103/PhysRevD.51.5905
Abstract: It is shown how the BRST quantization can be applied to a gauge invariant sector of theories with anomalously broken symmetries. This result is used to show that shifting the anomalies to a classically trivial sector of fields (Wess-Zumino mechanism) makes it possible to quantize the physical sector using a standard BRST procedure, as for a non anomalous theory. The trivial sector plays the role of a topological sector if the system is quantized without shifting the anomalies.
A Resolution Requirement for Disk Simulations Modeling Collapse
Andrew F. Nelson
Physics , 2003,
Abstract: The accurate simulation of collapsed objects requires that a huge range of spatial scales be well resolved if the result is not to be contaminated by numerically induced fragmentation. In this context, `insufficient resolution' means comparable to the local instability wavelength in the system. I define a minimum resolution criterion for simulations of disk systems, using the critical wavelength appropriate for disks.
Electron-phonon interaction in quantum-dot/quantum-well semiconductor heterostructures
F. Comas,Nelson Studart
Physics , 2003, DOI: 10.1103/PhysRevB.69.235321
Abstract: Polar optical phonons are studied in the framework of the dielectric continuum approach for a prototypical quantum-dot/quantum-well (QD/QW) heterostructure, including the derivation of the electron-phonon interaction Hamiltonian and a discussion of the effects of this interaction on the electronic energy levels. The particular example of the CdS/HgS QD/QW is addressed and the system is modelled according to the spherical geometry, considering a core sphere of material "1" surrounded by a spherically concentric layer of material "2", while the whole structure is embedded in a host matrix assumed as an infinite dielectric medium. The strength of the electron-LO phonon coupling is discussed in details and the polaronic corrections to both ground state and excited state electron energy levels are calculated. Interesting results concerning the dependence of polaronic corrections with the QD/QW structure size are analyzed.
High-field transport properties of bulk Si: A test for the Fokker-Planck approach
F. Comas,Nelson Studart
Physics , 1999,
Abstract: High electric-field transport parameters are calculated using an analytical Fokker-Planck approach (FPA), where transport is modeled as a drift-diffusion process in energy space. We have applied the theory to the case of Si, taking into account the six intervalley phonons, aiming to test the FPA. The obtained results show a quite reasonable agreement with experimental data and Monte Carlo simulations confirming in this case that the FPA works very well for high enough electric fields.
Page 1 /153670
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.