Journal of Next-Generation Research 5.0
Not a member yet
7559 research outputs found
Sort by
Prevalence of human respiratory syncytial virus infection in people with acute respiratory tract infections in Africa: A systematic review and meta-analysis
No full textInternational audienceAIM: The epidemiology of human respiratory syncytial virus (HRSV) infection has not yet been systematically investigated in Africa. This systematic review and meta-analysis are to estimate the prevalence of HRSV infections in people with acute respiratory tract infections (ARTI) in Africa.METHOD: We searched PubMed, EMBASE, Africa Journal Online, and Global Index Medicus to identify observational studies published from January 1, 2000, to August 1, 2017. We used a random-effects model to estimate the prevalence across studies. Heterogeneity (I2 ) was assessed via the chi-square test on Cochran's Q statistic. Review registration: PROSPERO CRD42017076352.RESULTS: A total of 67 studies (154 000 participants) were included. Sixty (90%), seven (10%), and no studies had low, moderate, and high risk of bias, respectively. The prevalence of HRSV infection varied widely (range 0.4%-60.4%). The pooled prevalence was 14.6% (95% CI 13.0-16.4, I2 = 98.8%). The prevalence was higher in children (18.5%; 95% CI 15.8-21.5) compared to adults (4.0%; 95% CI 2.2-6.1) and in people with severe respiratory tract infections (17.9%; 95% CI 15.8-20.1) compared to those with benign forms (9.4%; 95% CI 7.4-11.5); P-values <0.0001. The HRSV prevalence was not associated with sex, subregion in Africa, setting, altitude, latitude, longitude, and seasonality.CONCLUSION: This study suggests a high prevalence of HRSV in people with ARTI in Africa, particularly among children and people with severe clinical form. All innovative strategies to curb the burden should first focus on children which present the highest HRSV-related burden
Molecular characterization of human adenovirus associated with acute respiratory infections in Cameroon from 2011 to 2014
No full textInternational audienceBACKGROUND: Human adenoviruses (HAdVs) cause a wide range of diseases worldwide, including respiratory infections. Studies on HAdV molecular epidemiology are limited in Cameroon. The purpose of this study is to document the different types HAdV circulating in Cameroon in children with acute respiratory infections.METHODS: Nasopharyngeal swabs were collected from 811 children under 15 years from 2011 to 2014. The HAdV detection was assessed by semi-quantitative generic PCR r-gene®. The HAdV-positive samples were typed by amplification and sequencing of partial hexon gene and a real-time PCR. Demographic data were collected and analyzed. The infection and hospitalization risk factors were assessed thought the Chi-square test.RESULTS: A total of 137/220 HAdV-positive samples were amplified successfully. Six species of HAdV (Mastadenovirus A to F) were detected with B (108/220) and C (47/220) being the predominant strains. Hospitalization and age were significantly associated to HAdV-B and HAdV-C respectively. Phylogenetic analysis of HAdV-B3 virus (18) and B7 (5) shows a conserved and a significant temporal stability in relation to the reference sequence (99.1 to 100% of similarity).CONCLUSION: This study reported HAdV species and types detected in children with acute respiratory infections in Cameroon between September 2011 and July 2014. These results support further evaluation of the spatio-temporal circulation pattern of HAdV species and types in Cameroon
« La confusion des qualités de propriétaire et de preneur ne présume pas la confusion des obligations nées avant l’extinction du bail », note sous Cass. Civ. 3e, 30 novembre 2017, n° 16-23498
No full textnote 1123International audienc
Multi-scale multi-level marine spatial planning : a novel methodological approach applied in South Africa
No full textInternational audienceThis study proposes and discusses a multi-scale spatial planning method implemented simultaneously at local and national level to prioritize ecosystem management actions across landscapes and seascapes. Mismatches in scale between the occurrence of biodiversity patterns and ecological processes, and the size and nature of the human footprint, and the different levels and scope of governance, are a significant challenge in conservation planning. These scale mismatches are further confounded by data resolution disparities across and amongst the different scales. To address this challenge, we developed a multi-resolution scale-linked marine spatial planning method. We tested this approach in the development of a Conservation Plan for a significant portion of South Africa's exclusive economic zone, adjacent to the east coast province of KwaZulu-Natal (the SeaPlan project). The study's dataset integrated the geographic distribution of 390 biodiversity elements (spe-cies, habitats, and oceanographic processes) and 38 human activities. A multi-resolution system of planning unit layers (PUL), with individual PUs ranging in resolution from 0.2 to 10 km, was designed to arrange and analyse these data. Spatial priorities for conservation were selected incrementally at different scales, contributing conservation targets from the fine-, medium-and large-scale analyses, and from the coast to the offshore. Compared to a basic single-resolution scale-unlinked plan, our multi-resolution scale-linked method selects 6% less conservation area to achieve the same targets. Compared to a multi-resolution scale-unlinked plan, our method requires only an additional 5% area. Overall, this method reflects the multi-scale nature of marine social-ecological systems more realistically, is relatively simple and replicable, and serves to better connect fine-scale and large-scale spatial management policies. We discuss the impacts of this study on protected area expansion planning processes in South Africa. This study showcases a methodological advance that has the potential to impact marine spatial planning practices and policies
Human resources management practices and trade secret management: a configurational perspective
No full textInternational audienc
Influence of water temperature and food on the last stages of cultured pearl mineralization from the black-lip pearl oyster Pinctada margaritifera
No full textInternational audienceEnvironmental parameters, such as food level and water temperature, have been shown to be major factors influencing pearl oyster shell growth and molecular mechanisms involved in this biomineralization process. The present study investigates the effect of food level (i.e., microalgal concentration) and water temperature, in laboratory controlled conditions, on the last stages of pearl mineralization in order to assess their impact on pearl quality. To this end, grafted pearl oysters were fed at different levels of food and subjected to different water temperatures one month prior to harvest to evaluate the effect of these factors on 1) pearl and shell deposition rate, 2) expression of genes involved in biomineralization in pearl sacs, 3) nacre ultrastructure (tablet thickness and number of tablets deposited per day) and 4) pearl quality traits. Our results revealed that high water temperature stimulates both shell and pearl deposition rates. However, low water temperature led to thinner nacre tablets, a lower number of tablets deposited per day and impacted pearl quality with better luster and fewer defects. Conversely, the two tested food level had no significant effects on shell and pearl growth, pearl nacre ultrastructure or pearl quality. However, one gene, Aspein, was significantly downregulated in high food levels. These results will be helpful for the pearl industry. A wise strategy to increase pearl quality would be to rear pearl oysters at a high water temperature to increase pearl growth and consequently pearl size; and to harvest pearls after a period of low water temperature to enhance luster and to reduce the number of defects
Desert Kites: Were They Used For Hunting Or For Herding? A Review of the Recent Academic Literature
No full textInternational audienceSince the discovery of desert kites during the 1920s in southwestern Asia (where they are widely distributed) their possible functions have received much attention from archaeologists. Two main functions have been hypothesized, namely, kites primarily used either as game traps or as structures used for livestock husbandry. Two papers published in the 1990s expressed opposing views about the relevance of these different uses. During the last two decades much information has been gathered on kites as a result of archaeological excavations and satellite imaging. However the function or functions of desert kites remains uncertain. Starting from the 1990s debate, we revisit this controversial issue by reviewing the academic literature published since then. On the basis of this literature and other considerations, we conclude that although some (or all) may have been used for hunting, their main use was for the mustering of livestock. This favors the hypothesis of Echallier and Braemer (1995). In addition, it seems likely that kites were used for a third function, namely the capture of some wild or feral species of animals, particularly goats
Energy Management System in Micro-Grid with Storage and Hydrogen Production
No full textInternational audienceThis work proposes an Energy Management System (EMS) for a Micro-grid composed of a Photovoltaic system (PVs) with Maximum Power Point Tracking (MPPT), a Proton Exchange Membrane Fuel Cell (PEMFC), an electrolyzer and a storage system composed of batteries and hydrogen tanks. When PV production is lower than load demand, the lack of power demand is provided by the fuel cell with low dynamics and batteries with high dynamics. There current references are calculated using a constrained Explicit Model Predictive Control (EMPC) taking into account the dynamic of each element. When PV production is higher than load demand, the fuel cell is idle and its current reference is zero. According to the State of Charge (SoC) of the batteries, the storage elements charging current reference is balanced between them. The EMS performance is evaluated by simulation results
MARMIT: A multilayer radiative transfer model of soil reflectance to estimate surface soil moisture content in the solar domain (400–2500 nm)
No full textInternational audienceSurface soil moisture content (SMC) is known to impact soil reflectance at all wavelengths of the solar spectrum. As a consequence, many semi-empirical methods aim at inferring SMC from soil reflectance, but very few rely on physically-based models. This article presents a multilayer radiative transfer model of soil reflectance called MARMIT (multilayer radiative transfer model of soil reflectance) as a function of SMC given on a mass basis and a method called MARMITforSMC to estimate it from soil reflectance spectra. This model depicts a wet soil as a dry soil covered with a thin film of water. It is used to assess SMC over seven independent laboratory datasets gathered from the literature. A learning phase is required to link the thickness of the water film with the SMC. For that purpose, a sigmoid function, the parameters of which are related to soil physical and chemical properties such as porosity, grain size and mineralogy composition, is fitted. SMC can be inferred with good accuracy (RMSE ≈ 3%) if the learning step is applied soil by soil. The link between SMC and water thickness actually depends on soil texture and chemical composition. If the soils are divided into classes and if the learning phase is applied to a class, the RMSE slightly increases up to 5%. Finally, MARMITforSMC provides lower RMSE than any other existing semi-empirical or physically-based method
Perspectives on the use of growth rate patterns in fossil ectotherm bones to characterise ancient continental environments: Case study in Late Neogene sites from northern Chad (Djurab)
No full textInternational audienceWe investigate the feasibility and potential relevance of studying growth patterns in the bones of fossil freshwater ectotherms with the aim of developing new markers for continental palaeoenvironments and climates. This prospective study is based on Late Neogene material from Chad. It thus provides preliminary results that interest the reconstruction of paleoenvironments in ancient hominid bearing sites and that also document paleoenvironmental changes in continental Africa along a critical time period for global change. We prepared a set of various fish bones and turtle plates from Chadian Mio-Pliocene fossiliferous areas. We were able to analyse growth rates recorded during the course of the life of the animals in about half of the fossils initially sampled for the study. The main conclusions are: 1) the absence of a relationship between the external aspect of the fossils and the preservation of the growth marks, which means that visible features are not helpful in primary sampling; 2) at least in the Neogene Chadian sites, cathodoluminescence does not help to reveal growth marks; 3) growth rate patterns observed in the section of the body of the fin spines in claroteids, latids and polypterids and in pelomedusoid plates seem to be informative about environmental control of animal growth; and 4) depending on the taxa, different environmental informations can be obtained