6,756 research outputs found
Household food insecurity status and Hispanic immigrant childrenâs body mass index and adiposity
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
Research using hybrid pixel detectors in medical physics is on the rise. Timepix detectors have arrays of 256 Ă 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
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
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
Background: There is still lack of consensus on the benefitâharm balance of breast cancer screening. In this scenario, women's values and preferences are crucial for developing healthârelated 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 falseâpositive 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 falseâpositive 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
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/yr, compatible with the SFR as derived
from halpha calibrations (M/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
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
Recommended from our members
Direct Observation of Shock-Induced Disordering of Enstatite Below the Melting Temperature
We report in situ structural measurements of shock-compressed single crystal orthoenstatite up to 337 ± 55 GPa on the Hugoniot, obtained by coupling ultrafast X-ray diffraction to laser-driven shock compression. Shock compression induces a disordering of the crystalline structure evidenced by the appearance of a diffuse X-ray diffraction signal at nanosecond timescales at 80 ± 13 GPa on the Hugoniot, well below the equilibrium melting pressure (>170 GPa). The formation of bridgmanite and post-perovskite have been indirectly reported in microsecond-scale plate-impact experiments. Therefore, we interpret the high-pressure disordered state we observed at nanosecond scale as an intermediate structure from which bridgmanite and post-perovskite crystallize at longer timescales. This evidence of a disordered structure of MgSiO3 on the Hugoniot indicates that the degree of polymerization of silicates is a key parameter to constrain the actual thermodynamics of shocks in natural environments. © 2020. The Authors
Synthesis of titanate nanostructures using amorphous precursor material and their adsorption/photocatalytic properties
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
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 (2016â2019), undertaken to foster innovation in technologically-supported services for chronic multimorbid patients in Catalonia (ES) (7.5âM inhabitants). Whereas one of the assessment protocols is designed to evaluate population-based deployment of care coordination at regional level during the period 2011â2017, 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 (520âk 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 (216âk 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
- âŠ