6,558 research outputs found
Body Composition Impact on Sleep in Young Adults: The Mediating Role of Sedentariness, Physical Activity, and Diet
Obesity and sleep disturbances are both related to endocrine and metabolic alterations,
cardiovascular disease, and impaired daytime functioning and mood. However, the bidirectional
relationship between these conditions and the underlying mechanisms still remain unclear. This study
aimed to investigate the potential association of anthropometric and body composition parameters
with sleep in young adults, considering the mediating role of sedentariness, physical activity, and
diet. A total of 187 adults aged 18–25 (35.29% men) participated in the study. Body mass index (BMI),
waist–hip ratio, and waist–height ratio were calculated, and a dual-energy X-ray absorptiometry
scanner was used to assess body composition. Sedentary time and physical activity, as well as
sleep duration and quality, were objectively and subjectively measured using accelerometry and the
Pittsburgh Sleep Quality Index. An inverse association was found between BMI and total sleep time
(β = −0.165, p = 0.029). Waist–hip ratio and lean mass index were also negatively associated with total
sleep time (β = −0.222, p = 0.007, and β = −0.219, p = 0.004) and sleep efficiency (β = −0.174, p = 0.037,
and β = −0.188, p = 0.013). Sedentary time moderated by sex explained the association of BMI with
total sleep time such that a high BMI was related to higher sedentariness in men which, in turn, was
significantly associated with shorter sleep duration. Sedentary time is, therefore, a link/risk factor
mediating the association of high BMI with short sleep duration in healthy young men
Body Composition Impact on Sleep in Young Adults: The Mediating Role of Sedentariness, Physical Activity, and Diet
Obesity and sleep disturbances are both related to endocrine and metabolic alterations, cardiovascular disease, and impaired daytime functioning and mood. However, the bidirectional relationship between these conditions and the underlying mechanisms still remain unclear. This study aimed to investigate the potential association of anthropometric and body composition parameters with sleep in young adults, considering the mediating role of sedentariness, physical activity, and diet. A total of 187 adults aged 18–25 (35.29% men) participated in the study. Body mass index (BMI), waist–hip ratio, and waist–height ratio were calculated, and a dual-energy X-ray absorptiometry scanner was used to assess body composition. Sedentary time and physical activity, as well as sleep duration and quality, were objectively and subjectively measured using accelerometry and the Pittsburgh Sleep Quality Index. An inverse association was found between BMI and total sleep time (β = −0.165, p = 0.029). Waist–hip ratio and lean mass index were also negatively associated with total sleep time (β = −0.222, p = 0.007, and β = −0.219, p = 0.004) and sleep efficiency (β = −0.174, p = 0.037, and β = −0.188, p = 0.013). Sedentary time moderated by sex explained the association of BMI with total sleep time such that a high BMI was related to higher sedentariness in men which, in turn, was significantly associated with shorter sleep duration. Sedentary time is, therefore, a link/risk factor mediating the association of high BMI with short sleep duration in healthy young men
Organic and conventional dairy goat production systems in Andalusian mountainous areas
Organic goat production is poorly developed in Spain. Conventional dairy goat production
systems located in Andalusian mountainous areas greatly depend on pasturing which implies that its
transformation to organic model is not difficult. The objective of this paper is to evaluate the viability of
organic dairy goat farms –as compared to conventional–, and to study the possibilities of transitioning from
conventional to organic goat production. This study was carried out in 2006 in Sierra de Cádiz (Andalusia)
with the autochthonous breed Payoya. To monitor technico-economic aspects of goat farms, FAO-CIHEAM
method was implemented. Results indicate that organic farms are economically viable, due mainly to low
costs of external feeds and income from European Union subsidies. For transitioning from conventional to
organic dairy goat production a reduction of consumption of concentrates per animal and per year and/or
cultivate grain on the farm are necessary.La production caprine biologique est encore peu développée en Espagne. Les systèmes caprins
laitiers dans les zones de montagne de l’Andalousie disposent de grandes surfaces pour le pâturage, et,
par conséquent, il est assez facile de transformer ces systèmes en systèmes biologiques. L’objectif de ce
travail est d’évaluer la viabilité des systèmes caprins biologiques par rapport aux systèmes caprins
conventionnels et d’étudier les possibilités de conversion des systèmes conventionnels en systèmes
biologiques. L’étude a été réalisée en 2006 dans la Sierra de Cádiz (Andalousie) avec une race autochtone
(Payoya). On a utilisé la méthodologie FAO-CIHEAM pour le suivi technico-économique des exploitations
caprines. Les résultats montrent que les systèmes biologiques sont économiquement viables compte tenu
surtout des moindres coûts alimentaires par rapport aux systèmes conventionnels et des aides de l’Union
Européenne. Pour réussir la transformation des systèmes laitiers caprins conventionnels en systèmes
biologiques, il faut réduire l’apport de concentrés et essayer de les produire dans l’exploitation.Junta AndalucÃ
The soft X-ray and narrow-line emission of Mrk573 on kiloparcec scales
We present a study of the circumnuclear region of the nearby Seyfert galaxy
Mrk573 using Chandra, XMM-Newton and HST data. The X-ray morphology shows a
biconical region extending up to 12 arcsecs (4 kpc) in projection from the
nucleus. A strong correlation between the X-rays and the highly ionized gas
seen in the [O III] image is reported. Moreover, we have studied the line
intensities detected with the RGS/XMM-Newton and used them to fit the low
resolution EPIC/XMM-Newton and ACIS/Chandra spectra. The RGS spectrum is
dominated by emission lines of C VI, O VII, O VIII, Fe XVII, and Ne IX, among
others. A good fit is obtained using these emission lines found in the RGS
spectrum as a template for Chandra spectra of the nucleus and extended
emission. The photoionization model Cloudy provides a reasonable fit for both
the nuclear region and the cone-like structures. For the nucleus the emission
is modelled using two phases: a high ionization [log(U)=1.23] and a low
ionization [log(U)=0.13]. For the high ionization phase the transmitted and
reflected component are in a ratio 1:2, whereas for the low ionization the
reflected component dominates. For the extended emission, we successfully
reproduced the emission with two phases. The first phase shows a higher
ionization parameter for the NW (log(U)=0.9) than for the SE cone (log(U)=0.3).
The second phase shows a low ionization parameter (log(U)=-3) and is rather
uniform for NW and SE cones. In addition, the nuclear optical/infrared SED has
been modeled by a clumpy torus model. The torus bolometric luminosity agrees
with the AGN luminosity inferred from the observed hard X-ray spectrum. The
optical depth along the line of sight derived from the SED fit indicates a high
neutral column density in agreement with the classification of the nucleus as a
Compton-thick AGN.Comment: 15 pages, 14 figures, final version of the paper submitted to Ap
Inclusive Search for Anomalous Production of High-pT Like-Sign Lepton Pairs in Proton-Antiproton Collisions at sqrt{s}=1.8 TeV
We report on a search for anomalous production of events with at least two
charged, isolated, like-sign leptons with pT > 11 GeV/c using a 107 pb^-1
sample of 1.8 TeV ppbar collisions collected by the CDF detector. We define a
signal region containing low background from Standard Model processes. To avoid
bias, we fix the final cuts before examining the event yield in the signal
region using control regions to test the Monte Carlo predictions. We observe no
events in the signal region, consistent with an expectation of
0.63^(+0.84)_(-0.07) events. We present 95% confidence level limits on new
physics processes in both a signature-based context as well as within a
representative minimal supergravity (tanbeta = 3) model.Comment: 15 pages, 4 figures. Minor textual changes, cosmetic improvements to
figures and updated and expanded reference
A larger brown fat volume and lower radiodensity are related to a greater cardiometabolic risk, especially in young men
Objectives: Brown adipose tissue (BAT) is important in the maintenance of cardiometabolic health in rodents. Recent reports appear to suggest the same in humans, although if this is true remains elusive partly because of the methodological bias that affected previous research. This cross-sectional work reports the relationships of cold-induced BAT volume, activity (peak standardized uptake, SUVpeak), and mean radiodensity (an inverse proxy of the triacylglycerols content) with the cardiometabolic and inflammatory profile of 131 young adults, and how these relationships are influenced by sex and body weight.Design: This is a cross-sectional study.Methods: Subjects underwent personalized cold exposure for 2 h to activate BAT, followed by static F-18-fluorodeoxyglucose PET-CT scanning to determine BAT variables. Information on cardiometabolic risk (CMR) and inflammatory markers was gathered, and a CMR score and fatty liver index (FLI) were calculated.Results: In men, BAT volume was positively related to homocysteine and liver damage markers concentrations (independently of BMI and seasonality) and the FLI (all P 0.05).Conclusions: A larger BAT volume and a lower BAT mean radiodensity are related to a higher CMR, especially in young men, which may support that BAT acts as a compensatory organ in states of metabolic disruption.</p
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