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PubMed | Medicine Pharmacy and Dentistry Faculty and UCAD
Type: Journal Article | Journal: Public health | Year: 2015

To determine the periodontal factors associated with stroke in melanodermic subjects in Senegal.Case-control study.One hundred and twenty cases and 120 controls were included in this study. Cases had been diagnosed with stroke by a neurologist, with the diagnosis confirmed by scanner. Controls had never had any type of stroke. Data were collected regarding sociodemographic characteristics, lifestyle behaviours, general history, type of stroke (ischaemic or haemorrhagic) and periodontal parameters [plaque index, papillary bleeding index, pocket depth, clinical attachment loss, Community Periodontal Index of Treatment Needs and periodontitis (defined by clinical attachment loss >2 mm and pocket depth >3 mm)]. Logistic regression analysis was performed using R software to isolate a final model after adjustment for the 5% threshold.All periodontal characteristics were more common among cases than among controls. Periodontitis (odds ratio 1.58, 95% confidence interval 1.1-3.022) and periodontal parameters were significantly associated with stroke, adjusted for hypertension, sedentary lifestyle, and the interaction between periodontitis and age.Periodontal disease is associated with stroke in the Senegalese population. Prospective longitudinal studies should be undertaken to improve understanding.


Labou B.,UCAD | Brevault T.,BIOPASS | Brevault T.,CIRAD - Agricultural Research for Development | Bordat D.,UCAD | Diarra K.,UCAD
Crop Protection | Year: 2016

Conservation biological control, which fosters the optimal use of indigenous natural enemies, is a promising way for reducing pesticide reliance in horticultural systems. A two-year field survey was conducted in the main cabbage-producing area in Senegal (Niayes) to assess the potential of indigenous parasitoids to control populations of Plutella xylostella (Lepidoptera, Plutellidae). Results showed an overall low level of parasitism (11.7%) which was independent of host abundance, but was highly variable among fields (0–50%). Parasitism was predominant in the late part of dry season. Insecticide use, mostly relying on broad-spectrum insecticides, had a negative effect on the overall parasitism rate. Observations conducted throughout the cabbage crop cycle showed that parasitism unexpectedly decreased with crop aging (from 41 to 60 days post transplanting), likely due to repeated insecticide applications. Four main parasitoid species including Oomyzus sokolowskii (Kurdjumov) (Eulophidae) (48.8%), Apanteles litae Nixon (Braconidae) (32.5%), Brachymeria sp. (Chalcididae) (11.3%), and Cotesia vestalis Haliday (Braconidae) (7.3%) were identified. Parasitism due to O. sokolowskii was greater during the first part of the dry season whereas parasitism due to A. litae was greater during the second part of the dry season. Parasitism due to Brachymeria sp. was not affected by time of season but was greater in the Centre and North than in the South of Niayes. Parasitism due to C. vestalis was equal in the three zones but was higher in the late part of the dry season. The diversity of parasitoids was constant across zones but was greater during the second part of dry season. A positive relationship between diversity (Shannon diversity index H′) and parasitism rate was observed, suggesting a positive effect of parasitoid diversity on natural pest control. Parasitoids have a promising role to play as biocontrol agents of P. xylostella populations in Senegal, provided significant changes to current insecticide use are made. Better knowledge of their resource requirements including crop and non-crop habitats, and provision of these in and around crops is also needed. © 2016


Paeth H.,University of Würzburg | Hall N.M.,Toulouse 1 University Capitole | Gaertner M.A.,University of Castilla - La Mancha | Alonso M.D.,University of Castilla - La Mancha | And 13 more authors.
Atmospheric Science Letters | Year: 2011

We review the recent progress in dynamical and statistical downscaling approaches for west African precipitation and perform a regional climate model (RCM) intercomparison using the novel multi-model RCM data set from the Ensembles-based Predictions of Climate Changes and Their Impacts (ENSEMBLES) and African Monsoon Multidisciplinary Analyses (AMMA) projects. Present RCMs have distinct systematic errors in terms of west African precipitation varying in amplitude and pattern across models. This is also reflected in a relatively large spread in projected future precipitation trends. Altogether, the ENSEMBLES RCMs indicate a prevailing drying tendency in sub-Saharan Africa. Statistical post-processing of simulated precipitation is a promising tool to reduce systematic model errors before application in impact studies. Copyright © 2011 Royal Meteorological Society.


Diallo O.,University of Beira Interior | Rodrigues J.J.P.C.,University of Beira Interior | Sene M.,UCAD | Lloret J.,Polytechnic University of Valencia
Journal of Network and Computer Applications | Year: 2014

Wireless sensor networks (WSNs) have been the focus of many research works. Nowadays, because of the time-critical tasks of several WSN applications, one of the new challenges faced by WSNs is handling real-time storage and querying the data they process. This is the real-time database management on WSN and it deals with time-constrained data, time-constrained transactions, and limited resources of wireless sensors. Developing, testing, and debugging this kind of complex system are time-consuming and hard work. The deployment is also generally very costly in both time and money. Therefore in this context, the use of a simulator for a validation phase before implementation and deploying is proved to be very useful. The aim of this paper is to describe the different specificities of real-time databases on WSN and to present a model for a simulation framework of the real-time databases management on WSN that uses a distributed approach. Then, the model of the simulator is described and developed in Java and a case study with some results demonstrates the validity of the structural model. © 2013 Elsevier Ltd.


Sambou M.,Aix - Marseille University | Aubadie-Ladrix M.,Aix - Marseille University | Fenollar F.,Aix - Marseille University | Fall B.,Dakar Senegala | And 10 more authors.
Journal of Clinical Microbiology | Year: 2015

Biting midges of the genus Culicoides are implicated as vectors for a wide variety of pathogens. The morphological identification of these arthropods may be difficult because of a lack of detailed investigation of taxonomy for this species in Africa. However, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) profiling is efficient for arthropod identification at the species level. This study established a spectrum database of Culicoides spp. from Senegal using MALDITOF. Identification of Culicoides insects to the species level before mass spectrometry was performed on the basis of morphological characters. MALDI-TOF MS reference spectra were determined for 437 field-caught Culicoides of 10 species. The protein profiles of all tested Culicoides revealed several peaks with mass ranges of 2 to 20 kDa. In a validation study, 72 Culicoides specimens in the target species were correctly identified at the species level with a similarity of 95 to 99.9%. Four Culicoides protein profiles were misidentified. Nevertheless, six SuperSpectra (C. imicola, C. enderleini, C. oxystoma, C. kingi, C. magnus, and C. fulvithorax) were created. Abdomens of midges were used to amplify and sequence a portion of the mitochondrial cytochrome oxidase I gene (COI). The results obtained using the MALDI-TOF MS method were consistent with the morphological identification and similar to the genetic identification. Protein profiling using MALDI-TOF is an efficient approach for the identification of Culicoides spp., and it is economically advantageous for approaches that require detailed and quantitative information of vector species that are collected in field. The database of African Culicoides MS spectra created is the first database in Africa. The COI sequences of five Culicoides species that were previously noncharacterized using molecular methods were deposited in GenBank. © 2015, American Society for Microbiology. All Rights Reserved.


Diallo O.,University of Beira Interior | Rodrigues J.J.P.C.,University of Beira Interior | Rodrigues J.J.P.C.,Saint Petersburg State University of Information Technologies, Mechanics and Optics | Sene M.,UCAD | Lloret J.,Polytechnic University of Valencia
IEEE Transactions on Parallel and Distributed Systems | Year: 2015

In sensor networks, the large amount of data generated by sensors greatly influences the lifetime of the network. To manage this amount of sensed data in an energy-efficient way, new methods of storage and data query are needed. In this way, the distributed database approach for sensor networks is proved as one of the most energy-efficient data storage and query techniques. This paper surveys the state of the art of the techniques used to manage data and queries in wireless sensor networks based on the distributed paradigm. A classification of these techniques is also proposed. The goal of this work is not only to present how data and query management techniques have advanced nowadays, but also show their benefits and drawbacks, and to identify open issues providing guidelines for further contributions in this type of distributed architectures. © 1990-2012 IEEE.


Diallo O.,UCAD | Diallo O.,University of Beira Interior | Rodrigues J.J.P.C.,University of Beira Interior | Sene M.,UCAD
Journal of Network and Computer Applications | Year: 2012

In the recent past, search in sensor systems focused on node hardware constraints and very limited energy resources. But nowadays, that new applications need data processing with temporal constraints in their tasks; then one of the new challenges faced by wireless sensor networks (WSNs) is handling real-time storage and querying the data they process. Two main approaches to storage and querying data are generally considered warehousing and distributed. The warehousing approach stores data in a central database and then queries may be performed to it. In a distributed approach, sensor devices are considered as local databases and data are managed locally. The data collected by sensors must represent the current state of the environment; for this reason they are subject to logic and time constraints. Then, this paper identifies the main specifications of real-time data management and presents the available real-time data management solutions for WSNs, in order to discuss them and identify some open issues and provide guidelines for further contributions. © 2011 Elsevier Ltd. All rights reserved.


Diallo O.,University of Beira Interior | Rodrigues J.J.P.C.,University of Beira Interior | Sene M.,UCAD | Niu J.,Beihang University
Information Sciences | Year: 2014

Wireless body area networks (WBANs) have received a lot of attention from both academia and industry due to the increasing need of ubiquitous computing for eHealth applications, the continuous advances in miniaturization of electronic devices, and the ultra-low-power wireless technologies. In these networks, various sensors are attached either on clothes, on human body or even implanted under the skin for real-time health monitoring of patients in order to improve their independent daily lives. The energy constraints of sensors, the vital and large amount of data collected by WBAN nodes require powerful and secure storage, and a query processing mechanism that takes into account both real-time and energy constraints. This paper addresses these challenges and proposes a new architecture that combines a cloud-based WBANs with statistical modeling techniques in order to provide a secure storage infrastructure and optimize the real-time user query processing in terms of energy minimization and query latency. Such statistical model provides good approximate answers to queries with a given probabilistic confidence. Furthermore, the combination of the model with the cloud-based WBAN allows performing a query processing algorithm that uses the error tolerance and the probabilistic confidence interval as query execution criterions. The performance analysis and the experiments based on both real and synthetic data sets demonstrate that the new architecture and its underlying proposed algorithm optimize the real-time query processing to achieve minimal energy consumption and query latency, and provide secure and powerful storage infrastructure. © 2014 Elsevier Inc. All rights reserved.


PubMed | British Petroleum, UCAD, Center Hospitalier National and Institute Pasteur Of Tunis
Type: Journal Article | Journal: Primary care diabetes | Year: 2014

Many genetic association studies reported the contribution of KCNJ11 gene to type 2 diabetes susceptibility in different populations. We aimed to evaluate the association between E23K variant of KCNJ11 and type 2 diabetes in the Mauritanian population.We performed a case-control association study including 135 type 2 diabetes Mauritanian patients and 135 controls. Genotyping for the E23K variant was performed using a TaqMan allelic discrimination assay.We found significant association between KCNJ11 E23K variant and type 2 diabetes (Global model, OR=2.08, 95% CI=1.09-3.97, p=0.026). In the Moor ethnic group, E23K was also associated with type 2 diabetes in the general model (OR=2.08, 95% CI=1.09-3.97, p=0.026) and under the dominant model (OR=2.49, 95% CI=1.12-5.55, p=0.026). In the Mauritanians of African descent, KK genotype was not found. Besides, E23K variant was not associated with type 2 diabetes (OR=0.69, 95% CI=0.04-11.32, p=0.793).Our results revealed the risk of type 2 diabetes conferred by KCNJ11 E23K gene variant in the Mauritanian population.


PubMed | bioMerieux, Hopital Principal, French Institute of Health and Medical Research and UCAD
Type: Comparative Study | Journal: Journal of clinical microbiology | Year: 2015

Biting midges of the genus Culicoides are implicated as vectors for a wide variety of pathogens. The morphological identification of these arthropods may be difficult because of a lack of detailed investigation of taxonomy for this species in Africa. However, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) profiling is efficient for arthropod identification at the species level. This study established a spectrum database of Culicoides spp. from Senegal using MALDI-TOF. Identification of Culicoides insects to the species level before mass spectrometry was performed on the basis of morphological characters. MALDI-TOF MS reference spectra were determined for 437 field-caught Culicoides of 10 species. The protein profiles of all tested Culicoides revealed several peaks with mass ranges of 2 to 20 kDa. In a validation study, 72 Culicoides specimens in the target species were correctly identified at the species level with a similarity of 95 to 99.9%. Four Culicoides protein profiles were misidentified. Nevertheless, six SuperSpectra (C. imicola, C. enderleini, C. oxystoma, C. kingi, C. magnus, and C. fulvithorax) were created. Abdomens of midges were used to amplify and sequence a portion of the mitochondrial cytochrome oxidase I gene (COI). The results obtained using the MALDI-TOF MS method were consistent with the morphological identification and similar to the genetic identification. Protein profiling using MALDI-TOF is an efficient approach for the identification of Culicoides spp., and it is economically advantageous for approaches that require detailed and quantitative information of vector species that are collected in field. The database of African Culicoides MS spectra created is the first database in Africa. The COI sequences of five Culicoides species that were previously noncharacterized using molecular methods were deposited in GenBank.

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