Modeles mathematiques du mode temps monopartage des systemes informatiques d’entreprise

Principles of the models development of optimum management processes of access in the computers networks of the corporative information systems are reviewed and the results of the adequacy estimation of these models are presented.Dans le travail nous considérons les principes de conception des modèles de processus optimaux de contrôle d’accès dans les réseaux informatiques des systèmes informatiques d’entreprise et présentons les résultats d’évaluation de l’adéquation de ces modèles

Manganese pigmented anodized copper as solar selective absorber

The study concerns the optical and structural properties of layers obtained by a new efficient surface treatment totally free of chromium species. The process is made up of an anodic oxidation of copper in an alkaline solution followed by an alkaline potassium permanganate dipping post-treatment. Coatings, obtained at the lab and pilot scales, are stable up to 220 °C in air and vacuum, present low emissivity (0.14 at 70 °C) and high solar absorptivity (0.96), i.e. a suitable thermal efficiency (0.84 at 70 °C)

Assessment and adaptation of quinoa (Chenopodium quinoa Willd) to the agroclimatic conditions in Mali, West Africa: An example of South-North-South cooperation

Quinoa's adaptation was tested in Mali, West Africa, where the difficult agroclimatic conditions are similar to those in central northern Chile. The traditional varieties used were predominantly from Chile ('A64', 'BO25', 'BO78', 'PRP', 'PRJ', 'UDeC9', 'R49', 'VI-1', 'Regalona', 'Mix'), plus two crop cultivars from Argentina ('Roja Tastina' and 'Sajama') and one varietyfrom Bolivia. Trials began in 2007 and continue today. They tested sowing in the rainy season (June-Oct.) and in the dry season (Nov.- Mar.). Pests, diseases and yields were assessed, taking into account also the grain storage conditions and more sustainable soil management (compost). Some Altiplano cultivars were recalcitrant ('A64', 'R49' and 'MIX'), while the traditional varieties from central southern Chile gave satisfactory yields (1-2 tonnes/ha). Ideally, seeds should be sown each season to avoid a reduction in germination vigour which is caused by the ambient humidity and high temperatures characteristic of in situ storage in tropical zones. The crop cycle is 90-100 days for the accessions from Chile and up to 108-119 days for the accessions from Argentina. The panicles can be attacked by fungal diseases that reduce productivity in the rainy season. The presence of phytophagous insects (Bemisia, Aphis and Aspavia genera) was observed, as well as Coccinellidae, which are their natural predators in biological control. Quinoa has the potential to improve the supply of high quality protein in Africa. Pests in the rainy season and insect infestation can be controlled by adopting ecological management practices, using saponins from the same quinoa varieties. The limiting factor is the energy requirement for using water (not readily available in the dry season) and for mechanized threshing. The population's use and acceptance of quinoa can be expected to be high, on the basis of past experience introducing other crops from America (potato, maize and tomato) to this continent and given the culinary similarity with millet and rice. (Résumé d'auteur

Evaluación de quinoa (Chenopodium quinoa Willd.) y adaptación a las condiciones agroclimáticas de Mali, África Oeste: Un ejemplo de colaboración Sur-Norte-Sur

La adaptación de quinua en Mali, África del Oeste, se probó dada la similitud de las condiciones agroclimáticas estresantes con el centro-norte de Chile. Las variedades campesinas usadas fueron en su mayoría de Chile (A64, BO25, BO78, PRP, PRJ, UDeC9, R49, VI-1, Regalona, Mix) más dos cultivares de cosechas Argentinas (Roja Tastina y Sajama, variedad Boliviana) y uno más proveniente de Bolivia. Los ensayos comenzaron en el 2007 y se han extendido hasta el presente. Se probaron siembras en temporada de lluvias (junio a octubre) y en temporada seca (noviembre a marzo). Se evaluaron plagas, enfermedades y rendimientos considerando las condiciones ecológicas de almacenamiento de granos y manejos más sustentables del suelo (compost). Algunos cultivares altiplánicos resultaron recalcitrantes (A64, R49 y MIX) mientras que se tuvo rendimientos más aceptables (1-2 Ton/ ha) para las variedades campesinas del centro-sur de Chile. Las semillas deben idealmente sembrarse cada estación para evitar degradación de su vigor a la germinación por la humedad ambiental y altas temperaturas debido a condiciones naturales para la conservación in situ en zonas tropicales. El ciclo de cultivo puede ser desde 90-100 días para las accesiones de Chile, hasta 108-119 días para las accesiones de Argentina. Las panojas pueden ser atacadas por hongos que deciman la producción en la estación de lluvias. Se nota también la presencia de insectos fitófagos que pertenecen a los géneros Bemisia, Aphis, y Aspavia, mientras que Coccinélidos depredan sobre éstos, como control biológico. La quinua mejoraría la oferta proteica de alta calidad en África. Posibles plagas en temporadas húmedas, ataques de insectos son tal vez controlables con manejos ecológicos, usando saponinas de las mismas quinuas. Limitante será la energía para usar aguas no fácilmente disponibles en la estación seca y para el desaponficado mecánico. El uso y aceptación por la población puede estimarse alto dada la experiencia de introducción de otros cultivos de América (papas, maíz, tomates) en este continente y la similitud culinaria con el mijo y el arroz

Herpes Simplex Virus Type-2 Cervicovaginal Shedding Among Women Living With HIV-1 and Receiving Antiretroviral Therapy in Burkina Faso: An 8-Year Longitudinal Study.

BACKGROUND: The impact of antiretroviral therapy (ART) on herpes simplex virus type-2 (HSV-2) replication is unclear. The aim of this study was to assess factors associated with cervicovaginal HSV-2 DNA shedding and genital ulcer disease (GUD) in a cohort of women living with human immunodeficiency virus type-1 (HIV-1) in Burkina Faso. METHODS: Participants were screened for cervicovaginal HSV-2 DNA, GUD, cervicovaginal and systemic HIV-1 RNA, and reproductive tract infections every 3-6 months over 8 years. Associations with HSV-2 shedding and quantity were examined using random-effects logistic and linear regression, respectively. RESULTS: Of the 236 women with data on HSV-2 shedding, 151 took ART during the study period. Cervicovaginal HSV-2 DNA was detected in 42% of women (99 of 236) in 8.2% of visits (151 of 1848). ART was associated with a reduction in the odds of HSV-2 shedding, which declined for each year of ART use (odds ratio [OR], 0.74; 95% confidence interval [CI], .59-.92). In the multivariable model, the impact of ART was primarily associated with suppression of systemic HIV-1 RNA (adjusted OR, 0.32; 95% CI, .15-.67). A reduction in the odds of GUD was also observed during ART, mainly in those with HIV-1 suppression (adjusted OR, 0.53; 95% CI, .25-1.11). CONCLUSIONS: ART is strongly associated with a decrease in cervicovaginal HSV-2 shedding, and the impact was sustained over several years

Sampling constants in generalized Fock spaces

We discuss sampling constants for dominating sets in generalized Fock spaces.Comment: arXiv admin note: text overlap with arXiv:2004.0503

Epidemiology of Subpatent Plasmodium Falciparum Infection: Implications for Detection of Hotspots with Imperfect Diagnostics.

At the local level, malaria transmission clusters in hotspots, which may be a group of households that experience higher than average exposure to infectious mosquitoes. Active case detection often relying on rapid diagnostic tests for mass screen and treat campaigns has been proposed as a method to detect and treat individuals in hotspots. Data from a cross-sectional survey conducted in north-western Tanzania were used to examine the spatial distribution of Plasmodium falciparum and the relationship between household exposure and parasite density. Dried blood spots were collected from consenting individuals from four villages during a survey conducted in 2010. These were analysed by PCR for the presence of P. falciparum, with the parasite density of positive samples being estimated by quantitative PCR. Household exposure was estimated using the distance-weighted PCR prevalence of infection. Parasite density simulations were used to estimate the proportion of infections that would be treated using a screen and treat approach with rapid diagnostic tests (RDT) compared to targeted mass drug administration (tMDA) and Mass Drug Administration (MDA). Polymerase chain reaction PCR analysis revealed that of the 3,057 blood samples analysed, 1,078 were positive. Mean distance-weighted PCR prevalence per household was 34.5%. Parasite density was negatively associated with transmission intensity with the odds of an infection being subpatent increasing with household exposure (OR 1.09 per 1% increase in exposure). Parasite density was also related to age, being highest in children five to ten years old and lowest in those > 40 years. Simulations of different tMDA strategies showed that treating all individuals in households where RDT prevalence was above 20% increased the number of infections that would have been treated from 43 to 55%. However, even with this strategy, 45% of infections remained untreated. The negative relationship between household exposure and parasite density suggests that DNA-based detection of parasites is needed to provide adequate sensitivity in hotspots. Targeting MDA only to households with RDT-positive individuals may allow a larger fraction of infections to be treated. These results suggest that community-wide MDA, instead of screen and treat strategies, may be needed to successfully treat the asymptomatic, subpatent parasite reservoir and reduce transmission in similar settings

The combination of a blood test and Fibroscan improves the non-invasive diagnosis of liver fibrosis

Background and aims: Blood tests and liver stiffness evaluation (LSE) by ultrasonographic elastometry are accurate tools for diagnosing liver fibrosis. We evaluated whether their synchronous combination in new scores could improve the diagnostic accuracy and reduce liver biopsy requirement in algorithm. Methods: Three hundred and ninety patients with chronic liver disease of miscellaneous causes were included. Five blood fibrosis tests were evaluated: APRI, FIB-4, Hepascore, Fibrotest and FibroMeter. The reference was fibrosis Metavir staging. Results: Diagnosis of significant fibrosis (Metavir F≥2). The most accurate synchronous combination was FibroMeter+LSE, which provided a significantly higher area under the receiver operating characteristic curve (0.892) than LSE alone (0.867, P=0.011) or Fibrometer (0.834, P<10−3). An algorithm using the FibroMeter+LSE combination and then a liver biopsy in indeterminate cases had 91.9% diagnostic accuracy and required significantly fewer biopsies (20.2%) than previously published Bordeaux algorithm (28.6%, P=0.02) or sequential algorithm for fibrosis evaluation (SAFE) (55.7%, P<10−3). The Angers algorithm performance was not significantly different between viral hepatitis and other causes. Diagnosis of cirrhosis. The most accurate synchronous combination was LSE+FibroMeter, which provided ≥90% predictive values for cirrhosis in 90.6% of patients vs 87.4% for LSE (P=0.02) and 57.9% for FibroMeter (P<10−3). An algorithm including the LSE+FibroMeter combination, and then a liver biopsy in indeterminate cases, had a significantly higher diagnostic accuracy than the SAFE algorithm (91.0 vs 79.8%, P<10−3), and required significantly fewer biopsies than the Bordeaux algorithm (9.3 vs 25.3%, P<10−3). Conclusion: The synchronous combination of a blood test plus LSE improves the accuracy of the non-invasive diagnosis of liver fibrosis and, consequently, markedly decreases the biopsy requirement in the diagnostic algorithm, notably to <10% in cirrhosis diagnosis

A Trial of Early Antiretrovirals and Isoniazid Preventive Therapy in Africa

BACKGROUND: In sub-Saharan Africa, the burden of human immunodeficiency virus (HIV)-associated tuberculosis is high. We conducted a trial with a 2-by-2 factorial design to assess the benefits of early antiretroviral therapy (ART), 6-month isoniazid preventive therapy (IPT), or both among HIV-infected adults with high CD4+ cell counts in Ivory Coast. METHODS: We included participants who had HIV type 1 infection and a CD4+ count of less than 800 cells per cubic millimeter and who met no criteria for starting ART according to World Health Organization (WHO) guidelines. Participants were randomly assigned to one of four treatment groups: deferred ART (ART initiation according to WHO criteria), deferred ART plus IPT, early ART (immediate ART initiation), or early ART plus IPT. The primary end point was a composite of diseases included in the case definition of the acquired immunodeficiency syndrome (AIDS), non-AIDS-defining cancer, non-AIDS-defining invasive bacterial disease, or death from any cause at 30 months. We used Cox proportional models to compare outcomes between the deferred-ART and early-ART strategies and between the IPT and no-IPT strategies. RESULTS: A total of 2056 patients (41% with a baseline CD4+ count of ≥500 cells per cubic millimeter) were followed for 4757 patient-years. A total of 204 primary end-point events were observed (3.8 events per 100 person-years; 95% confidence interval [CI], 3.3 to 4.4), including 68 in patients with a baseline CD4+ count of at least 500 cells per cubic millimeter (3.2 events per 100 person-years; 95% CI, 2.4 to 4.0). Tuberculosis and invasive bacterial diseases accounted for 42% and 27% of primary end-point events, respectively. The risk of death or severe HIV-related illness was lower with early ART than with deferred ART (adjusted hazard ratio, 0.56; 95% CI, 0.41 to 0.76; adjusted hazard ratio among patients with a baseline CD4+ count of ≥500 cells per cubic millimeter, 0.56; 95% CI, 0.33 to 0.94) and lower with IPT than with no IPT (adjusted hazard ratio, 0.65; 95% CI, 0.48 to 0.88; adjusted hazard ratio among patients with a baseline CD4+ count of ≥500 cells per cubic millimeter, 0.61; 95% CI, 0.36 to 1.01). The 30-month probability of grade 3 or 4 adverse events did not differ significantly among the strategies. CONCLUSIONS: In this African country, immediate ART and 6 months of IPT independently led to lower rates of severe illness than did deferred ART and no IPT, both overall and among patients with CD4+ counts of at least 500 cells per cubic millimeter. (Funded by the French National Agency for Research on AIDS and Viral Hepatitis; TEMPRANO ANRS 12136 ClinicalTrials.gov number, NCT00495651.)