2,184 research outputs found
Étude de la prévalence des Vibrions Spp dans les produits de la pêche au Maroc
37 échantillons de poisson constitués de crevette rose (n=18) et de sardine (n=19) sont étudiés en vue d’évaluer l’incidence de la contamination des produits de la pêche par Vibrions spp. Les résultats obtenus montrent une prévalence globale du genre Vibrio de 81% dans l’ensemble des produits de la pêche analysés. Cette prévalence est plus importante dans les produits à risque (crustacés) avec une fréquence d’isolement de 83,3% contre 78,9% dans le poisson. Les résultats obtenus montrent également une prédominance de V. alginolyticus 78,3% dans l’ensemble des produits analysés.Mots-clés : Vibrions, incidence, produits de la pêche, Maroc
Hamilton-Jacobi scaling limits of Pareto peeling in 2D
Pareto hull peeling is a discrete algorithm, generalizing convex hull
peeling, for sorting points in Euclidean space. We prove that Pareto peeling of
a random point set in two dimensions has a scaling limit described by a
first-order Hamilton-Jacobi equation and give an explicit formula for the
limiting Hamiltonian, which is both non-coercive and non-convex. This contrasts
with convex peeling, which converges to curvature flow. The proof involves
direct geometric manipulations in the same spirit as Calder (2016).Comment: 50 pages, 18 figures; v2 improves exposition and extends main theorem
to cover any norm in R^
Impact of Caesarean section on subsequent fertility: a systematic review and meta-analysis.
STUDY QUESTION: Is there an association between a Caesarean section and subsequent fertility? SUMMARY ANSWER: Most studies report that fertility is reduced after Caesarean section compared with vaginal delivery. However, studies with a more robust design show smaller effects and it is uncertain whether the association is causal. WHAT IS KNOWN ALREADY: A previous systematic review published in 1996 summarizing six studies including 85 728 women suggested that Caesarean section reduces subsequent fertility. The included studies suffer from severe methodological limitations. STUDY DESIGN, SIZE, DURATION: Systematic review and meta-analysis of cohort studies comparing subsequent reproductive outcomes of women who had a Caesarean section with those who delivered vaginally. PARTICIPANTS/MATERIALS, SETTING, METHODS: Searches of Cochrane Library, Medline, Embase, CINAHL Plus and Maternity and Infant Care databases were conducted in December 2011 to identify randomized and non-randomized studies that compared the subsequent fertility outcomes after a Caesarean section and after a vaginal delivery. Eighteen cohort studies including 591 850 women matched the inclusion criteria. Risk of bias was assessed by the Newcastle-Ottawa scale (NOS). Data extraction was done independently by two reviewers. The meta-analysis was based on a random-effects model. Subgroup analyses were performed to assess whether the estimated effect was influenced by parity, risk adjustment, maternal choice, cohort period, and study quality and size. MAIN RESULTS AND THE ROLE OF CHANCE: The impact of Caesarean section on subsequent pregnancies could be analysed in 10 studies and on subsequent births in 16 studies. A meta-analysis suggests that patients who had undergone a Caesarean section had a 9% lower subsequent pregnancy rate [risk ratio (RR) 0.91, 95% confidence interval (CI) (0.87, 0.95)] and 11% lower birth rate [RR 0.89, 95% CI (0.87, 0.92)], compared with patients who had delivered vaginally. Studies that controlled for maternal age or specifically analysed primary elective Caesarean section for breech delivery, and those that were least prone to bias according to the NOS reported smaller effects. LIMITATIONS, REASONS FOR CAUTION: There is significant variation in the design and methods of included studies. Residual bias in the adjusted results is likely as no study was able to control for a number of important maternal characteristics, such as a history of infertility or maternal obesity. WIDER IMPLICATIONS OF THE FINDINGS: Further research is needed to reduce the impact of selection bias by indication through creating more comparable patient groups and applying risk adjustment
Analysis of Energy Conservation Options for USDOE Child Development Center, Final Summary Report
This report presents the results of a study that verifies the energy savings due to the individual
ECOs through the use of a calibrated DOE-2 simulation. The results show that roughly 73% of the savings estimated by the GSA architect can be accounted for by the calibrated simulation. This compares very well when one considers that the large differences were contributed by the envelope improvements and the clerestory windows. If these two ECOs were omitted, 90% of the savings can be accounted for by the calibrated simulation.The U.S.D.O.E. Forrestal Child Development Center (CDC) was designed to be a "showpiece" model building. Its construction included energy efficient features such as efficient lighting, a photovoltaic system, an energy management system, lighting controls, envelope improvements, clerestory windows, energy efficient heat pumps, and a solar hot water system. The architect's estimate of the energy savings from these measures totaled 31.6 million Watt-hours per year (MWh/yr), an annual savings of about 0.05/kWh). This study calculated a total annual energy savings of 23.2 MWh per year for the CDC; a savings of $1,160
Tuning of subspace predictive controls
Data-driven predictive control has recently gained increasing attention, as it makes it possible to design constrained controls directly from a set of data, without requiring an intermediate identification step. In this paper, we focus on a Subspace Predictive Control (SPC) scheme, with the aim of clarifying the sensitivity of the final closed-loop performance to its main hyperparameters, namely the length of the past horizon and the regularization penalties. Moreover, by delving deep into the structural properties of the control problem formulation, we provide a set of guidelines for the choice of such hyperparameters. The effectiveness of the resulting overall tuning strategy is assessed on two benchmark examples.</p
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Energy use for urban water management by utilities and Households in Los Angeles
Reducing energy consumption for urban water management may yield economic and environmental benefits. Few studies provide comprehensive assessments of energy needs for urban water sectors that include both utility operations and household use. Here, we evaluate the energy needs for urban water management in metropolitan Los Angeles (LA) County. Using planning scenarios that include both water conservation and alternative supply options, we estimate energy requirements of water imports, groundwater pumping, distribution in pipes, water and wastewater treatment, and residential water heating across more than one hundred regional water agencies covering over 9 million people. Results show that combining water conservation with alternative local supplies such as stormwater capture and water reuse (nonpotable or indirect potable) can reduce the energy consumption and intensity of water management in LA. Further advanced water treatment for direct potable reuse could increase energy needs. In aggregate, water heating represents a major source of regional energy consumption. The heating factor associated with grid-supplied electricity drives the relative contribution of energy-for-water by utilities and households. For most scenarios of grid operations, energy for household water heating significantly outweighs utility energy consumption. The study demonstrates how publicly available and detailed data for energy and water use supports sustainability planning. The method is applicable to cities everywhere
Seasonal hysteresis of surface urban heat islands
Temporal dynamics of urban warming have been extensively studied at the diurnal scale, but the impact of background climate on the observed seasonality of surface urban heat islands (SUHIs) remains largely unexplored. On seasonal time scales, the intensity of urban–rural surface temperature differences (ΔTs) exhibits distinctive hysteretic cycles whose shape and looping direction vary across climatic zones. These observations highlight possible delays underlying the dynamics of the coupled urban–biosphere system. However, a general argument explaining the observed hysteretic patterns remains elusive. A coarse-grained model of SUHI coupled with a stochastic soil water balance is developed to demonstrate that the time lags between radiation forcing, air temperature, and rainfall generate a rate-dependent hysteresis, explaining the observed seasonal variations of ΔTs. If solar radiation is in phase with water availability, summer conditions cause strong SUHI intensities due to high rural evaporative cooling. Conversely, cities in seasonally dry regions where evapotranspiration is out of phase with radiation show a summertime oasis effect controlled by background climate and vegetation properties. These seasonal patterns of warming and cooling have significant implications for heat mitigation strategies as urban green spaces can reduce ΔTs during summertime, while potentially negative effects of albedo management during winter are mitigated by the seasonality of solar radiation
Anakinra for systemic onset juvenile idiopathic arthritis: experience as a second versus first line treatment
An assessment of potential unintended consequences following a national antimicrobial stewardship programme in England: an interrupted time series analysis
Background: The 'Quality Premium' (QP) introduced in England in 2015 aimed to financially reward local healthcare commissioners for targeted reductions in primary care antibiotic prescribing. We aimed to evaluate possible unintended clinical outcomes related to this QP. Methods: Using Clinical Practice Research Datalink and Hospital Episode Statistics datasets, we examined general practitioner (GP) consultations (visits) and emergency hospital admissions related to a series of pre-defined conditions of unintended consequences of reduced prescribing. Monthly age and sex-standardised rates were calculated using a direct method of standardisation. We used segmented regression analysis of interrupted time series to evaluate the impact of the QP on seasonally adjusted outcome rates. Results: We identified 27,334 GP consultations and over five million emergency hospital admissions with pre-defined conditions. There was no evidence that the QP was associated with changes in GP consultation and hospital admission rates for the selected conditions combined. However, when each condition was considered separately, a significant increase in hospital admission rates was noted for quinsy, and significant decreases were seen for hospital-acquired pneumonia, scarlet fever, pyelonephritis and complicated urinary tract conditions. A significant decrease in GP consultation rates was estimated for empyema and scarlet fever. No significant changes were observed for other conditions. Conclusions: Findings from this study show that overall there was no significant association between the intervention and unintended clinical consequences, with the exception of a few specific conditions, most of which could be explained through other parallel policy changes or should be interpreted with caution due to small numbers
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