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Extreme hydrological phenomena recurrence in West Africa in recent decades is a problem in the anthropized watershed management. Link analysis between extreme hydrological phenomena and climate variability is necessary to guard against their consequences. However, qualitative data accessing difficulties and explanatory variable definition of extremes hydrological phenomena limit extreme flows rate studies. This study proposes the analysis the variability of the floods and the low flows at the Bianouan hydrometric station. Thus, five (5) floods characteristics variables (QCX5, QXJA, F90p, F95p and F99p) and three (3) for, the low flows (VCN10, QJNA and F10p) were extracted daily flows from the Bianouan hydrometric station from 1 January 1962 to 31 December 2005. The variability of these extremes has been studied by the trend analysis (linear regression) and of the stationarity (Pettitt and Hubert tests). The results show that for flood variables the negative trend is very significant and ruptures are observed in 1980. For low flow variables the negative trend is significant and the ruptures are observed in 1981. From this study, we can deduce that the ruptures observed in the rains and flows average in the end 1960s and early 1970s have affected later the extreme flows around the 1980s.

This study aims to determine the mechanisms of groundwater mineralization in the departments of Daloa and Zoukougbeu (Central West, Côte d’Ivoire). In order to achieve this, a hydrochemical study was carried out from seventeen (17) water samples (wells and sources) collected in March 2018. It was based on the multivariate statistical analysis techniques: The Principal Component Analysis (PCA) and the Hierarchical Cluster Analysis (HCA) were applied to physicochemical parameters. Thus, the average values of temperature, pH, electrical conductivity, Total Dissolved Solids (TDS) and Turbidity measured in situ in source waters are respectively 27.63°C; 4.81; 84.6 μS / cm; 38.45 mg. L-1 and 40.78 NTU and in well water 27.90°C; 4.78; 81.85μS/cm; 36.61 mg. L-1 and 27.22 NTU. The average concentrations of the major cations Ca2+, Mg2, Na+ and K+ of well water are respectively 2.26; 1.01; 4.58; 1.41 mg. L-1 and those of spring waters 2.18; 1.03; 5.50 and 2.07 mg.L-1. The major anions HCO3-, Cl-, SO42- and NO3- respectively amount to 8.81; 8.28; 5.33 and 7.67 mg.L-1 for well water and 11.77; 8.5; 5.27 and 8.25 mg.L-1 for spring waters. The PCA results show that three phenomena govern the mineralization of these waters. These are the phenomena of mineralization-residence time of water which is acquired by acid hydrolysis of the host rocks, spatial origin of lower quality of water and the grounds throughfall. These phenomena are confirmed by the Hierarchical Cluster Analysis (HCA). This work is therefore a tool for supporting groundwater management. Keywords: Groundwater, Mineralization, PCA, HCA, Central West, Côte d'Ivoire

[fr] Dans la région des Lacs, centre de la Côte d’Ivoire (Afrique de l’Ouest), l’alimentation en eau potable des populations rurales est assurée en majorité par les eaux souterraines contenues dans les aquifères discontinus cristallin et cristallophyllien. L’objet de cet article est d’évaluer les propriétés hydrauliques de ces aquifères afin d’entreprendre des études pour la gestion optimale de cette ressource. Pour ce faire, une compilation de données regroupant les fiches techniques de forage de même que les essais de pompage disponibles dans la région a été faite. L’interprétation des essais de pompage par la méthode de remontée de Jacob a permis de déterminer 105 valeurs de transmissivité (T ) et de débit spécifique (Q/s). Une analyse statistique des paramètres de forages et des paramètres hydrauliques déterminés a été réalisée. Les forages ont une profondeur totale qui varie de 49,50 à 99 m avec une moyenne de 69 m. L’épaisseur des altérites est comprise entre 1,90 et 63,10 m pour une moyenne de 16,52 m. Les forages ont un débit moyen de 2,32 m3/s. Les profondeurs de venues d’eau sont en moyenne de 42,94 m dans la roche non altérée. Les transmissivités et les débits spécifiques s’échelonnent sur trois ordres de grandeur avec des coefficients de variation supérieurs à 100% traduisant ainsi l’hétérogénéité structurale du milieu aquifère. Ces deux paramètres sont également distribués selon la loi log-normale au seuil de 10%. Une relation empirique significative entre la transmissivité et le débit spécifique a été établie. Elle permet d’estimer la transmissivité par l’expressionT = 0,937(Q/s)^1,118 avec R^2 = 0,82 dans un intervalle de confiance de 95% pour les aquifères de la zone d’étude. Ces résultats sont importants car, ils seront utiles dans les études de modélisation de ces aquifères et faciliteront la politique de gestion des eaux souterraines.

Copyright of Larhyss Journal is the property of Biskra University, Research Laboratory in Subterranean & Surface Hydraulics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Larhyss Journal is the property of Biskra University, Research Laboratory in Subterranean & Surface Hydraulics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Larhyss Journal is the property of Biskra University, Research Laboratory in Subterranean & Surface Hydraulics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

An inverse radiation treatment planning algorithm for Sensus Healthcare's Sculptura TM electronic brachytherapy system has been designed. The algorithm makes use of simulated annealing to optimize the conformation number (CN) of the treatment plan. The highly anisotropic dose distributions produced by the Sculptura TM x-ray source empower the inverse treatment planning algorithm to achieve highly conformal treatment plans for a wide range of prescribed planning target volumes. Over a set of 10 datasets the algorithm achieved an average CN of 0.79 ± 0.08 and an average gamma passing rate of 0.90 ± 0.10 at 5%/5 mm. A regularization term that encouraged short treatment plans was used, and it was found that the total treatment time could be reduced by 20% with only a nominal reduction in the CN and gamma passing rate. It was also found that downsampling the voxelized volume (from 320 3 to 64 3 voxels) prior to optimization resulted in a 150× speedup in the optimization time (from 2 + minutes to < 1 s) without affecting the quality of the treatment plan.

Integrating porous networks in load-bearing implants is essential in order to improve mechanical compatibility with the host tissue. Additive manufacturing has enabled the optimisation of the mechanical properties of metallic biomaterials, notably with the use of novel periodic regular geometries as porous structures. In this work, we successfully produced solid and lattice structures made of Ti-25Ta alloy with selective laser melting (SLM) using a Schwartz primitive unit-cell for the first time. The manufacturability and repeatability of the process was assessed through macrostructural and microstructural observations along with compressive testing. The mechanical properties are found to be suitable for bone replacement applications, showing significantly reduced elastic moduli, ranging from 14 to 36 GPa depending on the level of porosity. Compared to the conventionally used biomedical Ti-6Al-4V alloy, the Ti-Ta alloy offers superior mechanical compatibility for the targeted applications with lower elastic modulus, similar strength and higher ductility, making the Ti-25Ta alloy a promising candidate for a new generation of load-bearing implants., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Since the 1970s, the northern part of Côte d'Ivoire has experienced considerable fluctuation in its meteorology including a general decrease of rainfall and increase of temperature from 1970 to 2000, a slight increase of rainfall since 2000, a severe drought in 2004-2005 and flooding in 2006-2007. Such changing climate patterns might affect the transmission of malaria. The purpose of this study was to analyze climate and environmental parameters associated with malaria transmission in Korhogo, a city in northern Côte d'Ivoire. All data were collected over a 10-year period (2004-2013). Rainfall, temperature and Normalized Difference Vegetation Index (NDVI) were the climate and environmental variables considered. Association between these variables and clinical malaria data was determined, using negative binomial regression models. From 2004 to 2013, there was an increase in the annual average precipitation (1100.3-1376.5 mm) and the average temperature (27.2°C-27.5°C). The NDVI decreased from 0.42 to 0.40. We observed a strong seasonality in these climatic variables, which resembled the seasonality in clinical malaria. An incremental increase of 10 mm of monthly precipitation was, on average, associated with a 1% (95% Confidence interval (CI): 0.7 to 1.2%) and a 1.2% (95% CI: 0.9 to 1.5%) increase in the number of clinical malaria episodes one and two months later respectively. A 1°C increase in average monthly temperature was, on average, associated with a decline of a 3.5% (95% CI: 0.1 to 6.7%) in clinical malaria episodes. A 0.1 unit increase in monthly NDVI was associated with a 7.3% (95% CI: 0.8 to 14.1%) increase in the monthly malaria count. There was a similar increase for the preceding-month lag (6.7% (95% CI: 2.3% to 11.2%)). The study results can be used to establish a malaria early warning system in Korhogo to prepare for outbreaks of malaria, which would increase community resilience no matter the magnitude and pattern of climate change., Competing Interests: The authors have declared that no competing interests exist.

Background: Schistosomiasis is a water-based disease transmitted by trematodes belonging to the genus Schistosoma. The aim of this study was to assess the relationship between the prevalence of schistosomiasis and access to water, sanitation and hygiene (WASH) and environmental and socioeconomic factors in the city of Korhogo, northern Côte d'Ivoire., Methods: A cross-sectional study including 728 randomly selected households was conducted in Korhogo in March 2015. The heads of the households were interviewed about access to WASH and environmental and socioeconomic factors. All children abed between 5 and 15 years living in the households were selected to provide stool and urine samples for parasitological diagnosis of Schistosoma mansoni and Schistosoma haematobium infection. The relationship between infection with S. mansoni and potential risk factors was analysed by a mixed logistic regression model with 'household' as a random factor. Likelihood ratio tests were used to identify factors that were significantly associated with a Schistosoma spp. infection., Results: The overall prevalence of schistosomiasis among school-aged children in Korhogo was 1.9% (45/2341) composed of 0.3% (3/1248) S. haematobium and 3.5% (42/1202) S. mansoni. Due to the low prevalence of S. haematobium infection, risk factor analysis was limited to S. mansoni. Boys were 7.8 times more likely to be infected with S. mansoni than girls. Children between 10 and 15 years of age were 3.8 times more likely to be infected than their younger counterparts aged 5-10 years. Moreover, living in a house further away from a water access point (odds ratio [OR] = 0.29, 95% confidence interval [CI]: 0.13-0.70) and abstaining from swimming in open freshwater bodies (OR = 0.16, 95% CI: 0.04-0.56) were significantly associated with decreased odds of S. mansoni infection. The socioeconomic status did not appear to influence the prevalence of S. mansoni., Conclusions: A strategy to reduce the incidence of schistosomiasis should focus on health education to change the behaviour of populations at risk and encourage communities to improve sanitation and infrastructure in order to reduce contact with surface water.

Barriers to immunization are seen in both the general population and the health care workforce. We conducted this study to determine the perception of health workers on vaccination and the immunization of their patients. This cross-sectional descriptive analytical study was carried out among the medical staff in Bouaké, from 10 January to 07 March 2016. The data collected from the interviews were analyzed using Epi info 2000 software and SPSS 17.0. The Chi-2 test and logistic regression were performed and the significance threshold of the tests was 5%. The vaccination status of the 291 health care workers (HCWs) for the hepatitis B virus (HBV) was statistically related to their participation in the course in vaccination during their training (ORa = 1.69, 95% CI: 1.04-2.75 P<0.05) and the systematic verification of the vaccination status of the patient was statistically related to the vaccination status of the HCW (ORa = 4.33, 95% CI: 2.97-8.18, P<0.05). Promoting the vaccination among the population should be dependent on the promotion among HCWs., Competing Interests: Conflict of interest: the authors declare no potential conflict of interest.