6,677 research outputs found

    Household food insecurity status and Hispanic immigrant children’s body mass index and adiposity

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    Objectives: Despite the high prevalence rates of food insecurity and obesity among children of Hispanic immigrants, there has been a dearth of research on the direct relationship between food insecurity and obesity among this population. Further, prior research examining the association between food insecurity and body composition among children of Hispanic immigrants have not considered adiposity, specifically percent body fat (%BF) and waist circumference (WC), as outcome measurements. The following study contributes to the literature by examining the association between food insecurity and two adiposity measurements, %BF and WC, along with body mass index (BMI) among a sample of young Hispanic immigrant children. Methods: Cross-sectional survey and direct body composition assessments were collected among 49 low-income Hispanic immigrant children (mean age = 5.5. years) and their 44 mothers (mean age = 35.5 years) from two Houston-area community centers. Data were collected on household food security status using the 18-item USDA scale, demographic characteristics, and measured height, weight, body fat percentage, and waist circumference from children and mothers. Results: Sixty-five percent of children resided in a food insecure household, 31% of the children were obese in terms of %BF, and 24% were obese in terms of BMI. A greater percentage of food secure children were classified as obese in terms of %BF, BMI, and had an elevated waist circumference. A direct relationship was not observed between food insecurity and elevated waist circumference (OR = .08, p = .10); however, children living in food insecure households had 89% lower odds of having an elevated %BF (OR = 0.11, p \u3c .01), 93% lower odds of being obese (OR = 0.07, p \u3c .05), and 87% lower odds of being overweight/obese (OR = 0.13, p \u3c .05). Conclusions: In young children of Hispanic immigrants, food insecurity was related to healthier levels of %BF and BMI. Studies that track adiposity and weight status of children of Hispanic immigrants in relation to food insecurity over time are needed to further understand why food insecurity and obesity co-exist for some groups but not others

    Characterization of Structures of Equivalent Tissue With a Pixel Detector

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    Research using hybrid pixel detectors in medical physics is on the rise. Timepix detectors have arrays of 256 × 256 pixels with a resolution of 55 ÎŒm. Here, and by using Timepix counts instead of Hounsfield units, we present a calibration curve of a Timepix detector analog to those used for CT calibration. Experimentation consisted of the characterization of electron density in 10 different kinds of tissue equivalent samples from a CIRS 062M phantom (lung, 3 kinds of bones, fat, breast, muscle, water and air). Radiation of the detector was performed using an orthodontic X-ray machine at 70 KeV and .06 second of tube current with a purpose-built aluminum collimator. Data acquisition was performed at 1 frame per second and taking 3 frames per phantom. We were able to find a curve whose behavior was similar to others already published. This will lead to the verification of the usage of Timepix for identification of different tissues in an organ

    A Study of the Near-Ultraviolet Spectrum of Vega

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    UV, optical, and near-IR spectra of Vega have been combined to test our understanding of stellar atmospheric opacities, and to examine the possibility of constraining chemical abundances from low-resolution UV fluxes. We have carried out a detailed analysis assuming Local Thermodynamic Equilibrium (LTE) to identify the most important contributors to the UV continuous opacity: H, H−^{-}, C I, and Si II. Our analysis also assumes that Vega is spherically symmetric and its atmosphere is well described with the plane parallel approximation. Comparing observations and computed fluxes we have been able to discriminate between two different flux scales that have been proposed, the IUE-INES and the HST scales, favoring the latter. The effective temperature and angular diameter derived from the analysis of observed optical and near-UV spectra are in very good agreement with previous determinations based on different techniques. The silicon abundance is poorly constrained by the UV observations of the continuum and strong lines, but the situation is more favorable for carbon and the abundances inferred from the UV continuum and optical absorption lines are in good agreement. Some spectral intervals in the UV spectrum of Vega that the calculations do not reproduce well are likely affected by deviations from LTE, but we conclude that our understanding of UV atmospheric opacities is fairly complete for early A-type stars.Comment: 13 pages, 9 figures, to be published in Ap

    The Standard Model from a New Phase Transition on the Lattice

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    Several years ago it was conjectured in the so-called Roma Approach, that gauge fixing is an essential ingredient in the lattice formulation of chiral gauge theories. In this paper we discuss in detail how the gauge-fixing approach may be realized. As in the usual (gauge invariant) lattice formulation, the continuum limit corresponds to a gaussian fixed point, that now controls both the transversal and the longitudinal modes of the gauge field. A key role is played by a new phase transition separating a conventional Higgs or Higgs-confinement phase, from a phase with broken rotational invariance. In the continuum limit we expect to find a scaling region, where the lattice correlators reproduce the euclidean correlation functions of the target (chiral) gauge theory, in the corresponding continuum gauge.Comment: 16 pages, revtex, one figure. Clarifications made, mainly in sections 3 and 6 that deal with the fermion action, to appear in Phys Rev

    Systematic review on women's values and preferences concerning breast cancer screening and diagnostic services

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    Background: There is still lack of consensus on the benefit‐harm balance of breast cancer screening. In this scenario, women's values and preferences are crucial for developing health‐related recommendations. In the context of the European Commission Initiative on Breast Cancer, we conducted a systematic review to inform the European Breast Guidelines. Methods: We searched Medline and included primary studies assessing women's values and preferences regarding breast cancer screening and diagnosis decision making. We used a thematic approach to synthesise relevant data. The quality of evidence was determined with GRADE, including GRADE CERQual for qualitative research. Results: We included 22 individual studies. Women were willing to accept the psychological and physical burden of breast cancer screening and a significant risk of overdiagnosis and false‐positive mammography findings, in return for the benefit of earlier diagnosis. The anxiety engendered by the delay in getting results of diagnostic tests was highlighted as a significant burden, emphasising the need for rapid and efficient screening services, and clear and efficient communication. The confidence in the findings was low to moderate for screening and moderate for diagnosis, predominantly because of methodological limitations, lack of adequate understanding of the outcomes by participants, and indirectness. Conclusions: Women value more the possibility of an earlier diagnosis over the risks of a false‐positive result or overdiagnosis. Concerns remain that women may not understand the concept of overdiagnosis. Women highly value time efficient screening processes and rapid result delivery and will accept some discomfort for the peace of mind screening may provide

    Multiwavelength study of the star formation in the bar of NGC 2903

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    NGC 2903 is a nearby barred spiral with an active starburst in the center and Hii regions distributed along its bar. We aim to analyse the star formation properties in the bar region of NGC 2903 and study the links with the typical bar morphological features. A combination of space and ground-based data from the far-ultraviolet to the sub-millimeter spectral ranges is used to create a panchromatic view of the NGC 2903 bar. We produce two catalogues: one for the current star formation regions, as traced by the halpha compact emission, and a second one for the ultraviolet (UV) emitting knots, containing positions and luminosities. From them we have obtained ultraviolet colours, star formation rates, dust attenuation and halpha EWs, and their spatial distribution have been analysed. Stellar cluster ages have been estimated using stellar population synthesis models (Starburst99). NGC 2903 is a complex galaxy, with a very different morphology on each spectral band. The CO(J=1-0) and the 3.6 micron emission trace each other in a clear barred structure, while the halpha leads both components and it has an s-shape distribution. The UV emission is patchy and does not resemble a bar. The UV emission is also characterised by a number of regions located symmetrically with respect to the galaxy center, almost perpendicular to the bar, in a spiral shape covering the inner ~2.5 kpc. These regions do not show a significant halpha nor 24 micron emission. We have estimated ages for these regions ranging from 150 to 320 Myr, being older than the rest of the UV knots, which have ages lower than 10 Myr. The SFR calculated from the UV emission is ~0.4 M⊙_{\odot}/yr, compatible with the SFR as derived from halpha calibrations (M⊙_{\odot}/yr).Comment: Accepted for publication in A&

    Development of coccolithophore-based transfer functions in the western Mediterranean sea: a sea surface salinity reconstruction for the last 15.5 kyr

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    A new data set of 88 marine surface sediment samples and related oceanic environmental variables (temperature, salinity, chlorophyll <i>a</i>, oxygen, etc.) was studied to quantify the relationship between assemblages of coccolithophore species and modern environmental conditions in the western Mediterranean Sea and the Atlantic Ocean, west of the Strait of Gibraltar. Multivariate statistical analyses revealed that coccolithophore species were primarily related to sea surface salinity (SSS), explaining an independent and significant proportion of variance in the coccolithophore data. A quantitative coccolithophore-based transfer function to estimate SSS was developed using the modern analog technique (MAT) and weighted-averaging partial least square regression (WA-PLS). The bootstrapped regression coefficient (<i>R</i><sup>2</sup><sub>boot</sub>) was 0.85<sub>MAT</sub> and 0.80<sub>WA-PLS</sub>, with a root-mean-square error of prediction (RMSEP) of 0.29<sub>MAT</sub> and 0.30<sub>WA-PLS</sub> (psu). The resulting transfer function was applied to fossil coccolithophore assemblages in the highly resolved (~ 65 years) sediment core CEUTA10PC08 from the Alboran Sea (western Mediterranean) in order to reconstruct SSS for the last 25 kyr. The reliability of the reconstruction was evaluated by assessing the degree of similarity between fossil and modern coccolithophore assemblages and by a comparison of reconstructions with fossil ordination scores. Analogs were poor for the stadials associated with Heinrich events 2 and 1 and part of the Last Glacial Maximum. Good analogs indicate a more reliable reconstruction of the SSS for the last 15.5 kyr. During this period, several millennial and centennial SSS changes were observed and associated with sea-level oscillations and variations in the Atlantic Water entering the Alboran

    Synthesis of titanate nanostructures using amorphous precursor material and their adsorption/photocatalytic properties

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    This paper reports on a new and swift hydrothermal chemical route to prepare titanate nanostructures (TNS) avoiding the use of crystalline TiO2 as starting material. The synthesis approach uses a commercial solution of TiCl3 as titanium source to prepare an amorphous precursor, circumventing the use of hazardous chemical compounds. The influence of the reaction temperature and dwell autoclave time on the structure and morphology of the synthesised materials was studied. Homogeneous titanate nanotubes with a high length/diameter aspect ratio were synthesised at 160^{\circ}C and 24 h. A band gap of 3.06\pm0.03 eV was determined for the TNS samples prepared in these experimental conditions. This value is red shifted by 0.14 eV compared to the band gap value usually reported for the TiO2 anatase. Moreover, such samples show better adsorption capacity and photocatalytic performance on the dye rhodamine 6G (R6G) photodegradation process than TiO2 nanoparticles. A 98% reduction of the R6G concentration was achieved after 45 minutes of irradiation of a 10 ppm dye aqueous solution and 1 g/L of TNS catalyst.Comment: 29 pages, 10 figures, accepted for publication in Journal of Materials Scienc

    Evaluation of integrated care services in Catalonia: population-based and service-based real-life deployment protocols

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    Background: Comprehensive assessment of integrated care deployment constitutes a major challenge to ensure quality, sustainability and transferability of both healthcare policies and services in the transition toward a coordinated service delivery scenario. To this end, the manuscript articulates four different protocols aiming at assessing large-scale implementation of integrated care, which are being developed within the umbrella of the regional project Nextcare (2016–2019), undertaken to foster innovation in technologically-supported services for chronic multimorbid patients in Catalonia (ES) (7.5 M inhabitants). Whereas one of the assessment protocols is designed to evaluate population-based deployment of care coordination at regional level during the period 2011–2017, the other three are service-based protocols addressing: i) Home hospitalization; ii) Prehabilitation for major surgery; and, iii) Community-based interventions for frail elderly chronic patients. All three services have demonstrated efficacy and potential for health value generation. They reflect different implementation maturity levels. While full coverage of the entire urban health district of Barcelona-Esquerra (520 k inhabitants) is the main aim of home hospitalization, demonstration of sustainability at Hospital Clinic of Barcelona constitutes the core goal of the prehabilitation service. Likewise, full coverage of integrated care services addressed to frail chronic patients is aimed at the city of Badalona (216 k inhabitants). Methods: The population-based analysis, as well as the three service-based protocols, follow observational and experimental study designs using a non-randomized intervention group (integrated care) compared with a control group (usual care) with a propensity score matching method. Evaluation of cost-effectiveness of the interventions using a Quadruple aim approach is a central outcome in all protocols. Moreover, multi-criteria decision analysis is explored as an innovative method for health delivery assessment. The following additional dimensions will also be addressed: i) Determinants of sustainability and scalability of the services; ii) Assessment of the technological support; iii) Enhanced health risk assessment; and, iv) Factors modulating service transferability. Discussion: The current study offers a unique opportunity to undertake a comprehensive assessment of integrated care fostering deployment of services at regional level. The study outcomes will contribute refining service workflows, improving health risk assessment and generating recommendations for service selection.publishedVersio
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