169 research outputs found
Effects of a Lifestyle Program on Vascular Reactivity in Macro- and Microcirculation in Severely Obese Adolescents
Context and Objective: This study aimed to comprehensively assess the macro- and microcirculation of severely obese adolescents (SOA) and normal-weight counterparts and to determine the longitudinal effects of weight loss on vascular function in SOA. Design, Setting, Participants, and Outcome Measures: Seventeen SOA (body mass index z-score = 4.22 ± 0.73) and 19 puberty-matched normal-weight counterparts (body mass index z-score = â0.02 ± 1.04) were included. The SOA participated in a 4 month weight loss program. Brachial artery flow-mediated dilation and response to sublingual nitrate (nitrate-mediated dilation [NMD]) were assessed by high-resolution ultrasound. Microvascular reactivity was evaluated by laser Doppler flowmetry in response to NMD, iontophoresis of acetylcholine and sodium nitroprusside, and local hyperthermia. Plasma insulin, leptin, resistin, C-reactive protein, myeloperoxidase, and tissue plasminogen activator were measured. Results: At baseline, SOA had similar flow-mediated dilation and impaired NMD in the brachial artery compared to normal-weight adolescents. Similarly, peak responses to acetylcholine and sodium nitroprusside iontophoresis and to local hyperthermia were unaltered, whereas cutaneous blood flow after NMD was lower in the forearm microcirculation of SOA. All plasma measurements were significantly higher in SOA. After the 4-month program, SOA presented a weight reduction of 7.4 ± 3.1%, but neither brachial artery nor microvascular reactivity variables were improved. Significant decreases were detected in plasma leptin, myeloperoxidase, and tissue plasminogen activator. Conclusions: Macro- and microvascular endothelial function are preserved in adolescents with severe obesity. Conversely, weight loss does not improve their impaired smooth muscle response to exogenous organic nitrate in both vascular beds, despite reducing plasma markers adversely related to vascular homeostasis.This study was supported by grants from the French Society of Vascular Medicine 2010-2012 (to A.V. and A.P.M), and the Spanish Ministry of Health (CIBERobn CB12/03/30038) (to E.R.
High precision astrometry mission for the detection and characterization of nearby habitable planetary systems with the Nearby Earth Astrometric Telescope (NEAT)
(abridged) A complete census of planetary systems around a volume-limited
sample of solar-type stars (FGK dwarfs) in the Solar neighborhood with uniform
sensitivity down to Earth-mass planets within their Habitable Zones out to
several AUs would be a major milestone in extrasolar planets astrophysics. This
fundamental goal can be achieved with a mission concept such as NEAT - the
Nearby Earth Astrometric Telescope. NEAT is designed to carry out space-borne
extremely-high-precision astrometric measurements sufficient to detect
dynamical effects due to orbiting planets of mass even lower than Earth's
around the nearest stars. Such a survey mission would provide the actual
planetary masses and the full orbital geometry for all the components of the
detected planetary systems down to the Earth-mass limit. The NEAT performance
limits can be achieved by carrying out differential astrometry between the
targets and a set of suitable reference stars in the field. The NEAT instrument
design consists of an off-axis parabola single-mirror telescope, a detector
with a large field of view made of small movable CCDs located around a fixed
central CCD, and an interferometric calibration system originating from
metrology fibers located at the primary mirror. The proposed mission
architecture relies on the use of two satellites operating at L2 for 5 years,
flying in formation and offering a capability of more than 20,000
reconfigurations (alternative option uses deployable boom). The NEAT primary
science program will encompass an astrometric survey of our 200 closest F-, G-
and K-type stellar neighbors, with an average of 50 visits. The remaining time
might be allocated to improve the characterization of the architecture of
selected planetary systems around nearby targets of specific interest (low-mass
stars, young stars, etc.) discovered by Gaia, ground-based high-precision
radial-velocity surveys.Comment: Accepted for publication in Experimental Astronomy. The full member
list of the NEAT proposal and the news about the project are available at
http://neat.obs.ujf-grenoble.fr. The final publication is available at
http://www.springerlink.co
Western Indian Ocean marine and terrestrial records of climate variability: a review and new concepts on land-ocean interactions since AD 1660
We examine the relationship between three tropical and two subtropical western Indian Ocean coral oxygen isotope time series to surface air temperatures (SAT) and rainfall over India, tropical East Africa and southeast Africa. We review established relationships, provide new concepts with regard to distinct rainfall seasons, and mean annual temperatures. Tropical corals are coherent with SAT over western India and East Africa at interannual and multidecadal periodicities. The subtropical corals correlate with Southeast African SAT at periodicities of 16â30 years. The relationship between the coral records and land rainfall is more complex. Running correlations suggest varying strength of interannual teleconnections between the tropical coral oxygen isotope records and rainfall over equatorial East Africa. The relationship with rainfall over India changed in the 1970s. The subtropical oxygen isotope records are coherent with South African rainfall at interdecadal periodicities. Paleoclimatological reconstructions of land rainfall and SAT reveal that the inferred relationships generally hold during the last 350 years. Thus, the Indian Ocean corals prove invaluable for investigating landâocean interactions during past centuries
CD8+ T-Cell Interleukin-7 Receptor Alpha Expression as a Potential Indicator of Disease Status in HIV-Infected Children
Background: Initiation and modification of antiretroviral therapy in HIV-infected children depend on viral load and CD4+ T-cell count. However, these surrogates have limitations, and complementary immunological markers to assess therapeutic response are needed. Our aim was to evaluate CD8+ T-cell expression of CD127 as a marker of disease status in HIV-infected children, based on adult data suggesting its usefulness. We hypothesized that CD127 expression on CD8+ T-cells is lower in children with more advanced disease. Methods: In a cross-sectional evaluation, we used flow cytometry to measure CD127+ expression on CD8+ T-cells in whole blood from HIV-infected children with varying disease status. This was compared with expression of CD38 on this subset, currently used in clinical practice as a marker of disease status. Results: 51 HIV-infected children were enrolled. There was a strong positive correlation between CD127 expression on CD8+ T-cells and CD4+ T-cell count, and height and weight z-scores, and a strong negative correlation between CD127 expression and viral load. In contrast, we found no association between CD38 expression and these disease status markers. Conclusions: CD8+ T-cell CD127 expression is significantly higher in children with better HIV disease control, and may have a role as an immunologic indicator of disease status. Longitudinal studies are needed to determine the utility of this marker as a potential indicator of HIV disease progression
Wolves in the Wolds: Late Capitalism, the English Eerie, and the Wyrd Case of âOld Stinkerâ the Hull Werewolf
In this article, I depart from the earlier opinions of Emily Gerard, Sabine Baring-Gould, and others, who explained the disappearance of the werewolf in folklore as following the extinction of the wolf. I argue instead that British literature is distinctive in representing a history of werewolf sightings in places in Britain where there were once wolves. I draw on the idea of absence, manifestations of the English eerie, and the turbulence of England in the era of late capitalism to illuminate my analysis of the representation of contemporary werewolf sightingsPeer reviewe
Ăvolution de la contribution française Ă l'upgrade de LHCb
Ce document décrit l'évolution de la contribution française à l'upgrade de LHCb. Il s'inscrit dans le prolongement de la Lettre d'Intention [1], du Framework TDR [2], du document soumis au Conseil scientifique de l'IN2P3 le 21 juin 2012 [3], et des Technical Design Reports soumis au LHCC en novembre 2013 [4, 5]. Ces derniers concernent le détecteur de vertex et les détecteurs utilisés dans l'identification des particules. La contribution française s'est cristallisée autour de quatre grands projets : l'électronique front-end des calorimÚtres et du trajectographe à fibres scintillantes, le systÚme de déclenchement de premier niveau et la carte de lecture à 40MHz commune à l'ensemble des sous-systÚmes. Dans ce document nous décrivons les contributions envisagées et les ressources nécessaires pour mener à bien ces projets
The effects of ultraviolet B (UV-B) irradiation on color quality and decay rate of Capia pepper during postharvest storage
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Remote sensing data exploiration for geologic characterization of difficult targets : Laboratory Directed Research and Development project 38703 final report.
Characterizing the geology, geotechnical aspects, and rock properties of deep underground facility sites can enhance targeting strategies for both nuclear and conventional weapons. This report describes the results of a study to investigate the utility of remote spectral sensing for augmenting the geological and geotechnical information provided by traditional methods. The project primarily considered novel exploitation methods for space-based sensors, which allow clandestine collection of data from denied sites. The investigation focused on developing and applying novel data analysis methods to estimate geologic and geotechnical characteristics in the vicinity of deep underground facilities. Two such methods, one for measuring thermal rock properties and one for classifying rock types, were explored in detail. Several other data exploitation techniques, developed under other projects, were also examined for their potential utility in geologic characterization
Differing Requirements for RAD51 and DMC1 in Meiotic Pairing of Centromeres and Chromosome Arms in Arabidopsis thaliana
During meiosis homologous chromosomes pair, recombine, and synapse, thus ensuring accurate chromosome segregation and the halving of ploidy necessary for gametogenesis. The processes permitting a chromosome to pair only with its homologue are not fully understood, but successful pairing of homologous chromosomes is tightly linked to recombination. In Arabidopsis thaliana, meiotic prophase of rad51, xrcc3, and rad51C mutants appears normal up to the zygotene/pachytene stage, after which the genome fragments, leading to sterility. To better understand the relationship between recombination and chromosome pairing, we have analysed meiotic chromosome pairing in these and in dmc1 mutant lines. Our data show a differing requirement for these proteins in pairing of centromeric regions and chromosome arms. No homologous pairing of mid-arm or distal regions was observed in rad51, xrcc3, and rad51C mutants. However, homologous centromeres do pair in these mutants and we show that this does depend upon recombination, principally on DMC1. This centromere pairing extends well beyond the heterochromatic centromere region and, surprisingly, does not require XRCC3 and RAD51C. In addition to clarifying and bringing the roles of centromeres in meiotic synapsis to the fore, this analysis thus separates the roles in meiotic synapsis of DMC1 and RAD51 and the meiotic RAD51 paralogs, XRCC3 and RAD51C, with respect to different chromosome domains
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