30 research outputs found

    Monitoring and evaluating the impact of national school-based deworming in Kenya: study design and baseline results.

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    BACKGROUND: An increasing number of countries in Africa and elsewhere are developing national plans for the control of neglected tropical diseases. A key component of such plans is school-based deworming (SBD) for the control of soil-transmitted helminths (STHs) and schistosomiasis. Monitoring and evaluation (M&E) of national programmes is essential to ensure they are achieving their stated aims and to evaluate when to reduce the frequency of treatment or when to halt it altogether. The article describes the M&E design of the Kenya national SBD programme and presents results from the baseline survey conducted in early 2012. METHODS: The M&E design involves a stratified series of pre- and post-intervention, repeat cross-sectional surveys in a representative sample of 200 schools (over 20,000 children) across Kenya. Schools were sampled based on previous knowledge of STH endemicity and were proportional to population size. Stool (and where relevant urine) samples were obtained for microscopic examination and in a subset of schools; finger-prick blood samples were collected to estimate haemoglobin concentration. Descriptive and spatial analyses were conducted. The evaluation measured both prevalence and intensity of infection. RESULTS: Overall, 32.4% of children were infected with at least one STH species, with Ascaris lumbricoides as the most common species detected. The overall prevalence of Schistosoma mansoni was 2.1%, while in the Coast Province the prevalence of S. haematobium was 14.8%. There was marked geographical variation in the prevalence of species infection at school, district and province levels. The prevalence of hookworm infection was highest in Western Province (25.1%), while A. lumbricoides and T. trichiura prevalence was highest in the Rift Valley (27.1% and 11.9%). The lowest prevalence was observed in the Rift Valley for hookworm (3.5%), in the Coast for A. lumbricoides (1.0%), and in Nyanza for T. trichiura (3.6%). The prevalence of S. mansoni was most common in Western Province (4.1%). CONCLUSIONS: The current findings are consistent with the known spatial ecology of STH and schistosome infections and provide an important empirical basis on which to evaluate the impact of regular mass treatment through the school system in Kenya

    'It is like a tomato stall where someone can pick what he likes': structure and practices of female sex work in Kampala, Uganda.

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    BACKGROUND: Effective interventions among female sex workers require a thorough knowledge of the context of local sex industries. We explore the organisation of female sex work in a low socio-economic setting in Kampala, Uganda. METHODS: We conducted a qualitative study with 101 participants selected from an epidemiological cohort of 1027 women at high risk of HIV in Kampala. Repeat in-depth life history and work practice interviews were conducted from March 2010 to June 2011. Context specific factors of female sex workers' day-to-day lives were captured. Reported themes were identified and categorised inductively. RESULTS: Of the 101 women, 58 were active self-identified sex workers operating in different locations within the area of study and nine had quit sex work. This paper focuses on these 67 women who gave information about their involvement in sex work. The majority had not gone beyond primary level of education and all had at least one child. Thirty one voluntarily disclosed that they were HIV-positive. Common sex work locations were streets/roadsides, bars and night clubs. Typically sex occurred in lodges near bars/night clubs, dark alleyways or car parking lots. Overall, women experienced sex work-related challenges at their work locations but these were more apparent in outdoor settings. These settings exposed women to violence, visibility to police, a stigmatising public as well as competition for clients, while bars provided some protection from these challenges. Older sex workers tended to prefer bars while the younger ones were mostly based on the streets. Alcohol consumption was a feature in all locations and women said it gave them courage and helped them to withstand the night chill. Condom use was determined by clients' willingness, a woman's level of sobriety or price offered. CONCLUSIONS: Sex work operates across a variety of locations in the study area in Kampala, with each presenting different strategies and challenges for those operating there. Risky practices are present in all locations although they are higher on the streets compared to other locations. Location specific interventions are required to address the complex challenges in sex work environments

    LSST: from Science Drivers to Reference Design and Anticipated Data Products

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    (Abridged) We describe here the most ambitious survey currently planned in the optical, the Large Synoptic Survey Telescope (LSST). A vast array of science will be enabled by a single wide-deep-fast sky survey, and LSST will have unique survey capability in the faint time domain. The LSST design is driven by four main science themes: probing dark energy and dark matter, taking an inventory of the Solar System, exploring the transient optical sky, and mapping the Milky Way. LSST will be a wide-field ground-based system sited at Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m effective) primary mirror, a 9.6 deg2^2 field of view, and a 3.2 Gigapixel camera. The standard observing sequence will consist of pairs of 15-second exposures in a given field, with two such visits in each pointing in a given night. With these repeats, the LSST system is capable of imaging about 10,000 square degrees of sky in a single filter in three nights. The typical 5σ\sigma point-source depth in a single visit in rr will be ∌24.5\sim 24.5 (AB). The project is in the construction phase and will begin regular survey operations by 2022. The survey area will be contained within 30,000 deg2^2 with ÎŽ<+34.5∘\delta<+34.5^\circ, and will be imaged multiple times in six bands, ugrizyugrizy, covering the wavelength range 320--1050 nm. About 90\% of the observing time will be devoted to a deep-wide-fast survey mode which will uniformly observe a 18,000 deg2^2 region about 800 times (summed over all six bands) during the anticipated 10 years of operations, and yield a coadded map to r∌27.5r\sim27.5. The remaining 10\% of the observing time will be allocated to projects such as a Very Deep and Fast time domain survey. The goal is to make LSST data products, including a relational database of about 32 trillion observations of 40 billion objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures available from https://www.lsst.org/overvie

    LSST Science Book, Version 2.0

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    A survey that can cover the sky in optical bands over wide fields to faint magnitudes with a fast cadence will enable many of the exciting science opportunities of the next decade. The Large Synoptic Survey Telescope (LSST) will have an effective aperture of 6.7 meters and an imaging camera with field of view of 9.6 deg^2, and will be devoted to a ten-year imaging survey over 20,000 deg^2 south of +15 deg. Each pointing will be imaged 2000 times with fifteen second exposures in six broad bands from 0.35 to 1.1 microns, to a total point-source depth of r~27.5. The LSST Science Book describes the basic parameters of the LSST hardware, software, and observing plans. The book discusses educational and outreach opportunities, then goes on to describe a broad range of science that LSST will revolutionize: mapping the inner and outer Solar System, stellar populations in the Milky Way and nearby galaxies, the structure of the Milky Way disk and halo and other objects in the Local Volume, transient and variable objects both at low and high redshift, and the properties of normal and active galaxies at low and high redshift. It then turns to far-field cosmological topics, exploring properties of supernovae to z~1, strong and weak lensing, the large-scale distribution of galaxies and baryon oscillations, and how these different probes may be combined to constrain cosmological models and the physics of dark energy.Comment: 596 pages. Also available at full resolution at http://www.lsst.org/lsst/sciboo

    Feedback in simulations of disc-galaxy major mergers

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    Using hydrodynamic simulations of disc-galaxy major mergers, we investigate the star formation history and remnant properties when various parametrizations of a simple stellar feedback model are implemented. The simulations include radiative cooling, a density-dependent star formation recipe and a model for feedback from massive stars. The feedback model stores supernova feedback energy within individual gas particles and dissipates this energy on a time-scale specified by two free parameters; tau_fb, which sets the dissipative time-scale, and n, which sets the effective equation of state in star-forming regions. Using a self-consistent disc galaxy, modelled after a local Sbc spiral, in both isolated and major-merger simulations, we investigate parametrizations of the feedback model that are selected with respect to the quiescent disc stability. These models produce a range of star formation histories that are consistent with the star formation relation found by Kennicutt. All major mergers produce a population of new stars that is highly centrally concentrated, demonstrating a distinct break in the r1/4 surface density profile, consistent with previous findings. The half-mass radius and one-dimensional velocity dispersion are affected by the feedback model used. Finally, we compare our results to those of previous simulations of star formation in disc-galaxy major mergers, addressing the effects of star formation normalization, the version of smoothed particle hydrodynamics (SPH) employed and assumptions about the interstellar medium.Comment: update to match published versio

    Neuromuscular electrical stimulation and short-term recovery : implications for the performance in elite athletes

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    La pratique d’exercices intenses rĂ©pĂ©tĂ©s, entrecoupĂ©s de faibles temps de rĂ©cupĂ©ration, est susceptible d’engendrer une altĂ©ration de l’homĂ©ostasie et une diminution de la performance chez les sportifs soumis Ă  ce type de contraintes. Dans ce contexte, l’optimisation des processus de rĂ©cupĂ©ration est une possibilitĂ© forte d’amĂ©lioration de la performance et de sa reproduction. Une des principales limites au maintien de la performance de type haute intensitĂ©, rĂ©pĂ©tĂ© Ă  court terme, est attribuĂ©e Ă  la fatigue pĂ©riphĂ©rique, inhĂ©rente Ă  l’ensemble des mĂ©canismes de l’excitabilitĂ© et de la contraction du muscle squelettique. Cette fatigue pĂ©riphĂ©rique engendre une inadĂ©quation entre les apports et les besoins cellulaires, en oxygĂšne et en nutriments, ainsi qu’une incapacitĂ© Ă  Ă©liminer et/ou recycler les produits mĂ©taboliques issus de la contraction musculaire. Afin de limiter ces effets, l’augmentation du flux sanguin lors de l’exercice et de la rĂ©cupĂ©ration apparaĂźt indispensable au bon rĂ©tablissement de l’état d’équilibre de l’organisme et au maintien de la performance sportive. A ce titre, l’électrostimulation neuromusculaire semble ĂȘtre un mode de rĂ©cupĂ©ration thĂ©oriquement efficace pour augmenter le flux sanguin. Cette prĂ©sente thĂšse, comprenant trois Ă©tudes, visait Ă  connaĂźtre prĂ©cisĂ©ment les effets de l’électrostimulation neuromusculaire - par l’utilisation d’un nouvel appareil issu du domaine mĂ©dicale - sur la cinĂ©tique de rĂ©cupĂ©ration de marqueurs de performance, de marqueurs physiologiques et de perception, dans le contexte d’exercices intenses, rĂ©pĂ©tĂ©s Ă  court terme. Nous avons Ă©mis l’hypothĂšse qu’une stimulation efficace, induisant une augmentation du flux sanguin, permettrait d’optimiser la rĂ©cupĂ©ration Ă  court terme, entre deux exercices de haute intensitĂ©. Ces rĂ©sultats devraient permettre d’optimiser, dans le futur, les stratĂ©gies de rĂ©cupĂ©ration mises en place aprĂšs un exercice intense, rĂ©pĂ©tĂ© dans de brefs dĂ©laisThe practice of intense and repeated exercises, interrupted with short recovery times, may induce alterations in homeostasis and a decrease of the performance for athletes who are subject to this type of constraints. In this context, the optimization of the recovery processes is a strong possibility to improve performance and the maintain of it all along the competitive period. One of the main limits in the preservation of performance in type high-intensity, repeated at small interval of time, is attributed to the peripheral fatigue, inherent to all the mechanisms implied in the skeletal muscle excitability and contraction. This peripheral fatigue induces an inadequacy between the contributions and the cellular needs of oxygen and nutrients, and also a disability for disposal or recycling the metabolic by-products stemming from the muscular contraction. In order to limit these effects, the increase in blood flow during exercise and recovery seems essential for the good restoring of the state of physiological balance for the body and the preservation of sport performance. Therefore, the neuromuscular electrical stimulation seems to be, in theory, an effective recovery mode to improve the blood flow. This present thesis, comprising three studies, aimed to know precisely the effects of the neuromuscular electrical stimulation - by the use of a new device stemming from the medical field - on the kinetics of recovery of performance, physiological and perceptual markers, in the context of intense exercises repeated in the short terms. We hypothesized that an effective stimulation, increasing the blood flow would allow to optimize short-term recovery between two high-intensity exercises. These results should contribute to optimize, in the future, the strategies of recovery organized after an intense exercis

    Relationship Between Blood Flow and Performance Recovery: A Randomized, Placebo-Controlled Study

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    International audiencePurpose: To investigate the effect of different limb blood-flow levels on cycling-performance recovery, blood lactate concentration, and heart rate. Methods: Thirty-three high-intensity intermittent-trained athletes completed two 30-s Wingate anaerobic test sessions, 3 × 30-s (WAnT 1–3) and 1 × 30-s (WAnT 4), on a cycling ergometer. WAnT 1–3 and WAnT 4 were separated by a randomly assigned 24-min recovery intervention selected from among blood-flow restriction, passive rest, placebo stimulation, or neuromuscular electrical-stimulation-induced blood flow. Calf arterial inflow was measured by venous occlusion plethysmography at regular intervals throughout the recovery period. Performance was measured in terms of peak and mean power output during WAnT 1 and WAnT 4.Results: After the recovery interventions, a large (r = .68 [90% CL .42; .83]) and very large (r = .72 (90% CL .49; .86]) positive correlation were observed between the change in calf arterial inflow and the change in mean and peak power output, respectively. Calf arterial inflow was significantly higher during the neuromuscular-electrical-stimulation recovery intervention than with the blood-flow-restriction, passive-rest, and placebo-stimulation interventions (P .05). No recovery effect was linked to heart rate or blood lactate concentration levels.Conclusions: For the first time, these data support the existence of a positive correlation between an increase in blood flow and performance recovery between bouts of high-intensity exercise. As a practical consideration, this effect can be obtained by using neuromuscular electrical stimulation-induced blood flow since this passive, simple strategy could be easily applied during short-term recovery

    Microsats and Moby Dick: Microsatellite Support to Whale Science and Conservation

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    Scientists who study the 92 species of whales and dolphins (aka cetaceans) know that many populations are endangered. There may be only 12 vaquita porpoises left, and the ~450 North Atlantic Right whales are being decimated by ship collisions and fishing gear. Conservation efforts rely on implanted radio tags and satellite transponders to track cetaceans in 1.3 billion cubic kilometers of ocean. These efforts, however, are handicapped by technology and the limits of available satellite support. Leading cetologists surveyed in Booz Allen Hamilton’s Project WHALES (Whale/Habitat and Location/Environment Smallsats) agreed there are simply not enough tracking assets in space. The existing U.S.-led ARGOS radio tracking system needs to be supplemented with more satellites, especially in the tropical regions where ARGOS transceivers on polar-orbiting satellites leave gaps of up to two hours. A constellation of small satellites appears to be the most cost-effective way to achieve this objective. Cetologists can also benefit from partnerships with the increasing number of commercial Earth-observing microsatellite constellations. Imaging satellites with one-meter resolution can spot whales directly, while lower-resolution systems can track relevant phenomena like pollution plumes. Additionally, big-data analysis of tracking information and projecting tracks in a 3D environment with software like Booz Allen’s OceanLensℱ can multiply the utility of satellite tracking to scientists studying cetaceans and to naval forces trying to avoid injuring cetaceans. Small satellites may well be key to saving the largest animals on Earth
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