5,804 research outputs found
Associations of childcare type, age at start, and intensity with body mass index trajectories from 10 to 42 years of age in the 1970 British Cohort Study.
BACKGROUND: Attending childcare is related to greater childhood obesity risk, but there are few long-term follow-up studies. We aimed to examine the associations of childcare type, age at start, and intensity with body mass index body mass index (BMI) trajectories from ages 10 to 42 years. METHODS: The sample comprised 8234 individuals in the 1970 British Cohort Study, who had data on childcare attendance (no, yes), type (formal, informal), age at start (4-5, 3-3.99, 0-2.99 years old), and intensity (1, 2, 3, 4-5 days/week) reported at age 5 years and 32 563 BMI observations. Multilevel linear spline models were used to estimate the association of each exposure with the sample-average BMI trajectory, with covariate adjustment. A combined age at start and intensity exposure was also examined. RESULTS: Attending vs not attending and the type of childcare (none vs formal/informal) were not strongly related to BMI trajectories. Among participants who attended childcare 1 to 2 days a week, those who started when 3 to 3.99 years old had a 0.197 (-0.004, 0.399) kg/m2 higher BMI at age 10 years than those who started when 4 to 5 years old, and those who started when 0 to 2.99 years old had a 0.289 (0.049, 0.529) kg/m2 higher BMI. A similar dose-response pattern for intensity was observed when holding age at start constant. By age 42 years, individuals who started childcare at age 0 to 2.99 years and attended 3 to 5 days/week had a 1.356 kg/m2 (0.637, 2.075) higher BMI than individuals who started at age 4 to 5 years and attended 1 to 2 days/week. CONCLUSIONS: Children who start childcare earlier and/or attend more frequently may have greater long-term obesity risk.WJ is supported by the UK Medical Research Council (New Investigator Research Grant: MR/P023347/1) and acknowledges support from the National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, which is a partnership between University Hospitals of Leicester NHS Trust, Loughborough University, and the University of Leicester.
JA is funded by the Centre for Diet and Activity Research (CEDAR), a UKCRC Public Health Research Centre of Excellence which is funded by the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the National Institute for Health Research, and the Wellcome Trust (MRC administered grant MR/K023187/1)
2FGL J0846.0+2820: A new neutron star binary with a giant secondary and variable -ray emission
We present optical photometric and spectroscopic observations of the likely
stellar counterpart to the unassociated \emph{Fermi}-Large Area Telescope (LAT)
-ray source 2FGL J0846.0+2820, selected for study based on positional
coincidences of optical variables with unassociated LAT sources. Using optical
spectroscopy from the SOAR telescope, we have identified a late-G giant in an
eccentric ( = 0.06) 8.133 day orbit with an invisible primary. Modeling the
spectroscopy and photometry together lead us to infer a heavy neutron star
primary of and a partially stripped giant secondary of . H emission is observed in some of the spectra, perhaps
consistent with the presence of a faint accretion disk. We find the
-ray flux of 2FGL J0846.0+2820 dropped substantially in mid-2009,
accompanied by an increased variation in the optical brightness, and since then
it has not been detected by \emph{Fermi}. The long period and giant secondary
are reminiscent of the -ray bright binary 1FGL J1417.7--4407, which
hosts a millisecond pulsar apparently in the final stages of the pulsar
recycling process. The discovery of 2FGL J0846.0+2820 suggests the
identification of a new subclass of millisecond pulsar binaries that are the
likely progenitors of typical field millisecond pulsars.Comment: 12 pages, 8 figures, 3 tables. Accepted for publication in Ap
Positron annihilation spectrum from the Galactic Centre region observed by SPI/INTEGRAL, revisited: annihilation in a cooling ISM?
We analyse SPI/INTEGRAL data on the 511 keV line from the Galactic Centre,
accumulated over ~6 years of observations. We decompose the X-ray and soft
gamma-ray emission of the central part of the Milky Way into a relatively
compact "Bulge" and a more extended "Disk" components and report their spectral
properties. The Bulge component shows a prominent 511 keV line and essentially
no flux at 1.8 MeV, while the Disk component on the contrary contains a
prominent 1.8 MeV line and a very weak annihilation line. We show that the
spectral shape of the annihilation radiation (the narrow 511 keV line and the
associated othro-positronium continuum) is surprisingly well described by a
model of annihilation of hot positrons in a radiatively cooling interstellar
medium (ISM). The model assumes that positrons are initially injected into a
hot (~K), volume filling ISM, which is allowed to freely cool via
radiative losses. The annihilation time in such a medium is longer than the
cooling time for temperatures higher than a few ~K. Thus, most of the
positrons annihilate only after the gas has cooled down to ~K,
giving rise to annihilation emission characteristic of a warm, ionized ISM.Comment: 19 pages, 15 figures. Accepted by MNRA
Roughness of Interfacial Crack Front: Correlated Percolation in the Damage Zone
We show that the roughness exponent zeta of an in-plane crack front slowly
propagating along a heterogeneous interface embeded in a elastic body, is in
full agreement with a correlated percolation problem in a linear gradient. We
obtain zeta=nu/(1+nu) where nu is the correlation length critical exponent. We
develop an elastic brittle model based on both the 3D Green function in an
elastic half-space and a discrete interface of brittle fibers and find
numerically that nu=1.5, We conjecture it to be 3/2. This yields zeta=3/5. We
also obtain by direct numerical simulations zeta=0.6 in excellent agreement
with our prediction. This modelling is for the first time in close agreement
with experimental observations.Comment: 4 pages RevTeX
The use of natural resources to improve household income, health, and nutrition within the forests of Kianjavato, Madagascar
Understanding natural resource extraction in Madagascar is key to developing wider conservation and management strategies that ensure the continued delivery of essential ecosystem services, and the development of health and economic strategies to meet the demands of a growing human population. In the Kianjavato lowland rainforest of southeastern Madagascar, 78% of lemur species, 83% of native carnivoran species, and 67% of frugivorous bat species are threatened with extinction. All three of these groups of mammals are commonly hunted for food in other regions of Madagascar, yet we know little about current levels of hunting or whether the use of forest resources significantly affects human welfare in this region. We used health assessments of 1267 Kianjavato residents and semi-structured interviews of members of 336 households in 17 communities in Kianjavato to investigate human-environmental interactions. We found high prevalence of child and teenage malnutrition. More than half of the population under 20 years old was stunted, more than half was underweight, and more than one fifth was wasted. Further, one in six residents were anemic. We found that Kianjavato’s forests provided essential ecosystem services for its rural communities. As Kianjavato’s forests are altered to meet the needs of a growing human population, these direct-use ecosystem services (such as the use of wild animals for food or plants for medicine) are unable to similarly expand to meet the basic needs of the families living in these forests. A worrying proportion of the Kianjavato population depends on forests to meet their healthcare, nutritional, and economic needs, yet they may be failing to do so. All surveyed households (100%) depended on forests to meet their healthcare needs and 40% of the regional economy involved the extraction of finite forest resources (i.e., precious stones). Most households consumed very little wildlife (two animals per household per year) and the great majority (83%) of the forest animals they ate were not threatened with extinction. Forty percent of wildlife were caught illegally. Although hunting is likely not imperiling local wildlife at present, 16% of the Kianjavato population hunts wildlife and 20% are malnourished. The ecosystem services of Kianjavato’s forests may currently be insufficient to meet the needs of residents. Therefore, targeted efforts to increase local access to the healthcare system and to improve household nutrition and economy by improving the production and stability of local agricultural products may increase the long-term sustainability of both wildlife hunting, household incomes, and regional food security. Efforts such as these that can expand with the growing population to meet future needs may help secure the sustainable use of essential ecosystem services for the long term, improving the health of local people and maintaining the integrity of the forests in which they live. RésuméComprendre l'utilisation des ressources naturelles à Madagascar est essentiel pour développer des stratégies de conservation et de gestion plus larges qui permettent à la fois de fournir des services écosystémiques et de développer des stratégies sanitaires et économiques afin de répondre aux besoins d'une population humaine toujours croissante. Dans la forêt tropicale humide de basse altitude de Kianjavato dans le sud-est de Madagascar, 78% des espèces de lémuriens, 83% des espèces de carnivores indigènes et 67% des espèces de chauves-souris frugivores sont menacés d'extinction. Ces trois groupes de mammifères sont généralement chassés dans d'autres régions de Madagascar, mais nous en savons peu sur les niveaux actuels de chasse ou si l'utilisation des ressources forestières affecte significativement le bien-être humain dans cette région. Nous avons conduit une évaluation sanitaire sur 1267 habitants de Kianjavato, ainsi que des entretiens semi-structurés avec des membres de 336 ménages dans 17 communautés de Kianjavato afin d’étudier les interactions entre l’Homme et l’environnement. Nous avons constaté une forte prévalence de la malnutrition chez les enfants et les adolescents. Plus de la moitié de la population âgée de moins de 20 ans souffre d'un retard de croissance, plus de la moitié d’une insuffisance pondérale et plus d'un cinquième d’émaciation. En outre, un résident sur six est anémique. Nous avons constaté que les forêts de Kianjavato fournissent des services écosystémiques essentiels à ces communautés rurales. Comme les forêts de Kianjavato sont altérées pour répondre aux besoins d'une population croissante, ces services écosystémiques à usage direct (tels que la consommation d'animaux sauvages ou des plantes médicinales) ne peuvent plus couvrir les besoins fondamentaux des familles qui y vivent. Une proportion inquiétante de la population de Kianjavato dépend des forêts quant à ses besoins sanitaires, nutritionnels et économiques, cependant ces dernières ne peuvent plus y pourvoir entièrement. Tous les ménages enquêtés (100%) comptent sur la forêt pour la satisfaction de leurs besoins sanitaires. Par ailleurs, l’exploitation de ressources forestières finies (extraction de pierres précieuses) représente 40% de l’économie régionale. La plupart des ménages consommaient très peu d'animaux sauvages (deux animaux par ménage par an) et la grande majorité (83%) des animaux forestiers qu'ils mangeaient n'étaient pas menacés d'extinction. Cependant, 40% de ces animaux forestiers ont été capturés de manière illicite. Certes la chasse ne menace pas actuellement la faune locale mais 16% de la population de Kianjavato reconnaît s’y adonner et 20% souffrent de malnutrition. Les services écosystémiques s’avèrent actuellement insuffisants pour répondre aux besoins des résidents. Il est par conséquent nécessaire de cibler les efforts pour accroître l’accès local au système de santé, ensuite pour améliorer la nutrition et l’économie des ménages (améliorer la production et la stabilité des produits agricoles locaux), et tout ceci dans le but d’augmenter la viabilité à long terme de la chasse, des revenus et de la sécurité alimentaire dans cette région. De tels efforts lorsqu’ils prennent en compte la croissance de la population - et donc ses besoins futurs accrus —peuvent aider à assurer l’utilisation durable des services écosystémiques, à améliorer la santé des populations locales, et en fin de compte, à maintenir l’intégrité des forêts dans lesquelles elles vivent
The use of natural resources to improve household income, health, and nutrition within the forests of Kianjavato, Madagascar
Understanding natural resource extraction in Madagascar is key to developing wider conservation and management strategies that ensure the continued delivery of essential ecosystem services, and the development of health and economic strategies to meet the demands of a growing human population. In the Kianjavato lowland rainforest of southeastern Madagascar, 78% of lemur species, 83% of native carnivoran species, and 67% of frugivorous bat species are threatened with extinction. All three of these groups of mammals are commonly hunted for food in other regions of Madagascar, yet we knew little about current levels of hunting or whether the use of forest resources significantly affects human welfare in this region. We used health assessments of 1 267 Kianjavato residents and semi-structured interviews of members of 336 households in 1 7 communities in Kianjavato to investigate human-environmental interactions. We found high prevalence of child and teenage malnutrition. More than half of the population under 20 years old was stunted, more than half was underweight, and more than one fifth was wasted. Further, one in six residents were anemic. We found that Kianjavato’s forests provided essential ecosystem services for its rural communities. As Kianjavato’s forests are altered to meet the needs of a growing human population, these direct-use ecosystem services (such as the use of wild animals for food or plants for medicine) are unable to similarly expand to meet the basic needs of the families living in these forests. A worrying proportion of the Kianjavato population depends on forests to meet their healthcare, nutritional, and economic needs, yet they may be failing to do so. All surveyed households (1 00%) depended on forests to meet their healthcare needs and 40% of the regional economy involved the extraction of finite forest resources (i.e., precious stones). Most households consumed very little wildlife (two animals per household per year) and the great majority (83%) of the forest animals they ate were not threatened with extinction. Forty percent of wildlife were caught illegally. Although hunting is likely not imperiling local wildlife at present, 1 6% of the Kianjavato population hunts wildlife and 20% are malnourished. The ecosystem services of Kianjavato’s forests may currently be insufficient to meet the needs of residents. Therefore, targeted efforts to increase local access to the healthcare system and to improve household nutrition and economy by improving the production and stability of local agricultural products may increase the long-term sustainability of wildlife hunting, household incomes, and regional food security. Efforts such as these that can expand with the growing population to meet future needs may help secure the sustainable use of essential ecosystem services for the long term, improving the health of local people and maintaining the integrity of the forests in which they live
Renal Proliferative and Phenotypic Changes in Rats With Two-Kidney, One-Clip Goldblatt Hypertension
Angiotensin II (All) is a vasoconstrictive peptide with hypertrophic and mitogenic effects on many cell types. Previous studies have shown that in vivo administration of All in rats results in proliferation of, and phenotypic changes in, many renal cell populations, but in doses also causing hypertension. Thus, it was not possible to differentiate nonhemodynamic from hypertensive effects of All. Therefore, we studied rats with renin-dependent, All-mediated hypertension (the two-kidney, oneclip Goldblatt model; mean systolic blood pressure 238 ± 48 ν 140 ± 6 mm Hg in sham-operated controls). The undipped kidneys, which were exposed to high blood pressure, developed significant glomerular and tubulointerstitial injury, tubulointerstitial cell proliferation, dense focal interstitial monocyte-macrophage influx, increased deposition of types I and IV collagen, as well as increased cellular expression of desmin and actin, in tubulointerstitial areas when examined at 11 weeks. In contrast, clipped kidneys, protected from hypertension but with high local renin expression, had minimal abnormalities. These studies suggest that in this model increased renin, and presumably All, does not mediate significant proliferative or phenotypic changes in the kidney in the absence of hypertension at 11 weeks. Am J Hypertens 1994;7:177-18
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Fabrication of Multi-Layered Carbon Structures Using LCVD
Others have used Laser Chemical Vapor Deposition (LCVD) to create 3-D fibrous
structures and helical springs. Current research efforts focus on the creation of more advanced
three-dimensional carbon objects through the use of multi-layered deposition. Multi-layered
structures require an understanding of interlayer adhesion and the propagation of geometric
anomalies through multiple layers. An important aspect in minimizing these shape anomalies is
the implementation of closed loop temperature control. Several laminated carbon structures are
presented with discussions and observations about the fabrication process and visual
characteristics of each. The major issues in using LCVD to create multi-layer carbon structures
are addressed.McDonald Observator
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