89 research outputs found

    Controllability Metrics on Networks with Linear Decision Process-type Interactions and Multiplicative Noise

    Full text link
    This paper aims at the study of controllability properties and induced controllability metrics on complex networks governed by a class of (discrete time) linear decision processes with mul-tiplicative noise. The dynamics are given by a couple consisting of a Markov trend and a linear decision process for which both the "deterministic" and the noise components rely on trend-dependent matrices. We discuss approximate, approximate null and exact null-controllability. Several examples are given to illustrate the links between these concepts and to compare our results with their continuous-time counterpart (given in [16]). We introduce a class of backward stochastic Riccati difference schemes (BSRDS) and study their solvability for particular frameworks. These BSRDS allow one to introduce Gramian-like controllability metrics. As application of these metrics, we propose a minimal intervention-targeted reduction in the study of gene networks

    Rural Sanitation and CLTS Monitoring and Evaluation: Experiences of Post-Certification Monitoring in West and Central Africa

    Get PDF
    This Sanitation and Hygiene Hunter-Gatherer Thematic Notes discusses the challenges and potential solutions in relation to post-ODF monitoring in West and Central Africa. The ultimate goal of CLTS is to end open defecation (OD) and sustain an open defecation free (ODF) status. Maintaining ODF status and moving up the sanitation ladder is closely linked to the sustainability of interventions. While the monitoring and evaluation during the process of CLTS until certification is well-defined for all countries, the monitoring and evaluation of the maintaining of ODF status is a major problem and is central to the sustainabilityof achievements in rural sanitation. This note is a summary review of the constraints and challenges, existing or potential solutions and emerging issues in relation to post-certification monitoring. It is based on the sharing of experiences from West and Central African countries participating in the workshop mentioned above. Although it is limited in terms, it can serve as a basis for a detailed study contributing to the understanding of the thematics for sustainability of CLTS specifically and of rural sanitation in general

    Représentations, saisonnalité et prise en charge du paludisme infantile simple : le cas des femmes Sénoufo de Sikasso (Mali)

    Full text link
    Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal

    Securing water resources to build community resilience to water threats and climate variability in the Sahel

    Get PDF
    This paper describes an approach to strengthen water security of communities living in water stressed parts of the Sahel. Threats to water security such as climate variability, climate change, growing demand, deforestation, erosion, pollution and poor service sustainability impact water availability and quality for domestic, livestock and livelihood needs, sometimes resulting in conflict. WaterAid’s Securing Water Resources Approach (SWRA) involves collectively identifying threats that are likely to manifest themselves using participatory monitoring of groundwater, rainfall and surface water. Information from monitoring feeds into risk based planning aimed at agreeing allocations between water users as well as improvements to services. SWRA strengthens the link between communities and local government institutions that might assist with conflict resolution and service level improvements. The overall goal is to strengthen local level resilience to water related threats, complementing national plans for water resource management and climate change adaptation

    Profil Evolutif et Comorbidités des Troubles Fonctionnels Intestinaux (TFI) Persistants au CHU de Conakry

    Get PDF
    Introduction : Les troubles fonctionnels digestifs (TFI) ou syndrome de l’intestin irritable représentent un véritable problème de santé publique. Si cette affection n’engage pas le pronostic vital, elle altère significativement et de façon chronique la qualité de vie des malades. L’étiologie est mal connue et de nombreux facteurs sont impliqués. Méthodes : Il s’agissait d’une étude transversale descriptive à recueil prospectif de données réalisée en consultation externe du service d’hépato-gastroentérologie de l’hôpital national Donka du CHU de Conakry allant du 1er Janvier 2019 au 31 Décembre 2020 chez les patients souffrants de TFI et répondant aux critères de Rome IV. Résultats : Trois cent quatre-vingt-dix-huit cas de SII sur 1309 patients soit une prévalence de 30,40%. On notait une prédominance féminine avec un sex ratio de 0,92. L’âge moyen de nos patients était de 49 ans avec des extrêmes de 10 et 88 ans. Les tranches d’âge de 25-34 ans et 35-44 ans étaient les plus représentées avec des fréquences respectives de 24,52% et 22,07%. Les principaux signes cliniques étaient des douleurs abdominales (92,28%), de la constipation dans 84,41%, ballonnement abdominal 28,39% et diverses manifestations extradigestives : insomnie dans 32,08%, de céphalées dans 30,55% des cas, de la fibromyalgie 22,91%. Les principaux facteurs déclenchants étaient : les facteurs psychologiques 32,08% et alimentaires (tubercules 14,13%, haricot 6,11%, le diner tardif et ou copieux 4,2% et les boissons gazeuses 3,44%). Le retentissement socioprofessionnel des TFI était dominé par l’absentéisme dans 82,78% des cas, le retard au travail dans 20%. Les comorbidités digestives les plus fréquentes étaient : le RGO, la dyspepsie, le dolichocôlon ainsi que leur association. Conclusion  Le SII est un problème de santé publique qui altère la qualité de vie des personnes atteintes. Les douleurs abdominales, la constipation et le ballonnement abdominal en constituent la triade symptomatique. Le stress est un facteur déclenchant de la symptomatologie. L’association du SII avec des comorbidités digestives et extra-digestives est fréquente. Introduction : Functional digestive disorders (TFI) or irritable bowel syndrome represent a real public health problem. Although this condition is not life-threatening, it significantly and chronically alters the quality of life of patients. The etiology is poorly understood and many factors are involved. Methods : This was a descriptive cross-sectional study with prospective data collection carried out in outpatient consultation of the hepato-gastroenterology department of the Donka national hospital of the Conakry University Hospital from January 1, 2019 to December 31, 2020 in patients suffering from TFI and meeting the Rome IV criteria. Results: Three hundred and ninety-eight cases of IBS out of 1309 patients, representing a prevalence of 30.40%. There was a female predominance with a sex ratio of 0.92. The average age of our patients was 49 years with extremes of 10 and 88 years. The age groups of 25-34 and 35-44 were the most represented with respective frequencies of 24.52% and 22.07%. The main clinical signs were abdominal pain (92.28%), constipation in 84.41%, abdominal bloating in 28.39% and various extradigestive manifestations: insomnia in 32.08%, headache in 30.55% of cases. cases, fibromyalgia 22.91%. The main triggering factors were: psychological factors 32.08% and dietary factors (tubers 14.13%, beans 6.11%, late or heavy dinner 4.2% and soft drinks 3.44%). The socio-professional impact of TFIs was dominated by absenteeism in 82.78% of cases, lateness for work in 20%. The most common digestive comorbidities were: GERD, dyspepsia, dolichocolon and their combination. Conclusion IBS is a public health problem that impairs the quality of life of those affected. Abdominal pain, constipation and abdominal bloating constitute the symptomatic triad. Stress is a triggering factor for the symptoms. The association of IBS with digestive and extra-digestive comorbidities is common

    Vector competence of Aedes vexans (Meigen), Culex poicilipes (Theobald) and Cx. quinquefasciatus Say from Senegal for West and East African lineages of Rift Valley fever virus

    Get PDF
    Background Rift Valley fever virus (RVFV; Phlebovirus, Bunyaviridae) is a mosquito–borne, zoonotic pathogen. In Senegal, RVFV was first isolated in 1974 from Aedes dalzieli (Theobald) and thereafter from Ae. fowleri (de Charmoy), Ae. ochraceus Theobald, Ae. vexans (Meigen), Culex poicilipes (Theobald), Mansonia africana (Theobald) and Ma. uniformis (Theobald). However, the vector competence of these local species has never been demonstrated making hypothetical the transmission cycle proposed for West Africa based on serological data and mosquito isolates. Methods Aedes vexans and Cx. poicilipes, two common mosquito species most frequently associated with RVFV in Senegal, and Cx. quinquefasciatus, the most common domestic species, were assessed after oral feeding with three RVFV strains of the West and East/central African lineages. Fully engorged mosquitoes (420 Ae. vexans, 563 Cx. quinquefasciatus and 380 Cx. poicilipes) were maintained at 27 ± 1 °C and 70–80 % relative humidity. The saliva, legs/wings and bodies were tested individually for the RVFV genome using real-time RT-PCR at 5, 10, 15 and 20 days post exposure (dpe) to estimate the infection, dissemination, and transmission rates. Genotypic characterisation of the 3 strains used were performed to identify factors underlying the different patterns of transmission. Results The infection rates varied between 30.0–85.0 % for Ae. vexans, 3.3–27 % for Cx. quinquefasciatus and 8.3–46.7 % for Cx. poicilipes, and the dissemination rates varied between 10.5–37 % for Ae. vexans, 9.5–28.6 % for Cx. quinquefasciatus and 3.0–40.9 % for Cx. poicilipes. However only the East African lineage was transmitted, with transmission rates varying between 13.3–33.3 % in Ae. vexans, 50 % in Cx. quinquefasciatus and 11.1 % in Cx. poicilipes. Culex mosquitoes were less susceptible to infection than Ae. vexans. Compared to other strains, amino acid variation in the NSs M segment proteins of the East African RVFV lineage human-derived strain SH172805, might explain the differences in transmission potential. Conclusion Our findings revealed that all the species tested were competent for RVFV with a significant more important role of Ae. vexans compared to Culex species and a highest potential of the East African lineage to be transmitted

    Why didn’t you write this in your diary? Or how nurses (mis)used clinic diaries to (re)claim shared reflexive spaces in Senegal

    Get PDF
    Between 2015 and 2017, we implemented the clinic diaries project as part of the qualitative component of an evaluation of a supply chain intervention for family planning in Senegal. This project combined different tools including the diaries and participatory workshops with nurses. At the intersection between writings and silences, this paper explores the role played by the clinic diaries to mediate ethnographic encounters, and the iterative nature of ‘doing fieldwork’ to produce knowledge in hierarchical health systems. This paper also reflects on the processes through which the diaries created a space where accounts of lived experiences routinely unfolding in health facilities could be shared, in the context of a health system increasingly dominated by metrics, performances and vertical reporting mechanisms. The clinic diaries research process therefore sheds light on the limits of approaching bureaucratic norms and practices as coming from the top, an approach reinforced by data reporting and coordination mechanisms in the Senegalese pyramidal health system. In contrast, the diaries suggest a role for participative ethnography to identify collegial spaces to reflect on shared experiences in and of bureaucratic spaces. </jats:p

    Critical insights on the demographic concept of "birth spacing": locating Nef in family well-being, bodies, and relationships in Senegal.

    Get PDF
    Birth spacing has emerged since the early 1980s as a key concept to improve maternal and child health, triggering interest in birth spacing practices in low-income countries, and drawing attention to prevailing norms in favour of long birth intervals in West Africa. In Senegal, the Wolof concept of Nef, which means having children too closely spaced in time, is morally condemned and connotes a resulting series of negative implications for family well-being. While Nef and "birth spacing" intersect in key ways, including acknowledging the health benefits of longer birth intervals, they are not translations of each other, for each is embedded in distinct broader cultural and political assumptions about social relations. Most notably, proponents of the demographic concept of birth spacing assume that the practice of using contraception after childbearing to postpone births could contribute to "empowering" women socially. In Senegal, by contrast, preventing Nef (or short birth intervals) is also viewed as strengthening family well-being by allowing women to care more fully for their family. This paper draws on policy documents and interviews to explore women's and men's understanding of Nef, and in turn critically reflect on the demographic concept of birth spacing. Our findings reinforce the relevance of the concept of birth spacing to engage with women and men around family planning services in Senegal. Accounts of the Nef taboo in Senegal also show that social norms stigmatising short birth intervals can legitimise constraints faced by women on control of their body

    Tuberculose intestinale révélée par une occlusion intestinale aigüe au cours d’une réaction paradoxale au traitement anti-tuberculeux chez un patient immunocompétent: à propos d’un cas et revue de la littérature

    Get PDF
    La tuberculose intestinale représente 3 à 5% de toutes les localisations viscérales. Malgré l'efficacité démontrée des anti-tuberculeux, des cas d'exacerbation du tableau clinique initial ont été décrits à l'initiation du traitement. Ces réactions dites «paradoxales» sont cependant rarement rapportées chez les immunocompétents et beaucoup moins sous forme d'occlusion intestinale. Nous rapportons un cas de tuberculose intestinale révélée par une occlusion intestinale aigüe au cours d'une réaction paradoxale aux anti-tuberculeux. Il s'agit d'un patient de 26 ans, immunocompétent qui a présenté un syndrome occlusif à un mois de traitement d'une tuberculose pleuro-pulmonaire. La tomodensitométrie (TDM) abdominale était en faveur d'une occlusion intestinale grêlique. La laparotomie objectivait une masse intra-péritonéale avec de multiples adhérences. L'examen anatomopathologique de la pièce opératoire était en faveur d'une tuberculose intestinale. L'évolution était favorable après la poursuite du traitement anti-tuberculeux initial

    Facteurs associés à la dissociation immunovirologique chez les patients infectés par le VIH-1 sous traitement antirétroviral hautement actif au Centre de Traitement Ambulatoire (CTA) de Dakar

    Get PDF
    Introduction: L'objectif de ce travail était d'évaluer les différents facteurs associés à la dissociation immunovirologique malgré un traitement antirétroviral hautement actif et efficace.Méthodes: Il s'agissait d'une étude de cohorte historique, descriptive et analytique faite à partir de dossiers de patients infectés par le VIH-1; sous traitement antirétroviral depuis au moins 12 mois, suivis dans la cohorte du CTA de 2001 à 2011 et ayant une charge virale indétectable depuis 6 mois.Résultats: Durant cette période d'étude de 10 ans, la prévalence de la DIV était de 19,3%. Le sexe féminin était prédominant avec un sexe ratio de 1,9. La dissociation immunovirologique a été plus fréquemment rencontrée chez les patients de sexe masculin (29,7% vs 14,1%) avec une différence statistiquement significative (p = 0,00006). L'âge médian était de 44 ans ± 10 ans. Un antécédent de tuberculose a été retrouvé dans environ un tiers des cas (31,4%). La dissociation immunovirologique était significativement plus fréquente chez les patients ayant un antécédent de tuberculose (p = 0,00005). La plupart des patients (68%) était au stade SIDA 3 ou 4 de l'OMS. Les patients ayant une dissociation immunovirologique étaient plus souvent aux stades 3 et 4 de l'OMS (p = 0,0001). La dénutrition a été notée dans plus de la moitié des cas (56,2%) et la dissociation immunovirologique prédominait chez les patients dénutris (p=0,005). Le taux moyen de lymphocytes TCD4+ était de 86,7± 83 cellules / mm3. La dissociation immunovirologique était plus fréquente chez les patients ayant un taux de lymphocytes TCD4 bas à l'initiation avec une différence statistiquement significative (p = 0,00000). En analyse multivariée; Seuls l'âge supérieur ou égal à 43 ans, le taux de CD4 initial &lt; 100 c/mm3 et le sexe masculin étaient significativement associés à cette dissociation immunovirologique.Conclusion: Les principaux facteurs associés à la dissociation immunovirologique étant évalués, d'autres études portant sur ce groupe mériteraient d'être envisagées afin de connaitre l'impact de cette réponse immunologique partielle sur la survenue d'infections opportunistes ou bien la mise en place d'une trithérapie spécifique uniquement dans le but d'avoir une restauration immunologique optimale.Mots clés: Dissociation, immunovirologique, VIH, DakarEnglish Title: Factors associated with immunovirologic dissociation in HIV-1-infected patients under highly active antiretroviral therapy in the Ambulatory Treatment Center (ATC) in DakarEnglish AbstractIntroduction: the objective of this work is to evaluate the different factors associated with immunovirologic dissociation despite highly active and effective antiretroviral treatment.Methods: we conducted a retrospective, cohort, descriptive and analytical study of the medical records of HIV-1 infected patients having received at least 12 months of antiretroviral therapy, followed in the ATC cohort from 2001 to 2011 and with undetectable viral load in the last 6 months.Results: during this 10-year study period, the prevalence of IVD was 19.3%. Female sex was predominant, with a sex ratio of 1.9. Immunovirologic dissociation was more frequent in male patients (29.7% vs 14.1%) with a statistically significant difference (p = 0,00006). The average age was 44 years ± 10 years. A history of tuberculosis was found in about a third of the cases (31.4%). Immunovirologic dissociation was significantly more frequent in patients with a history of tuberculosis (p = 0.00005). Most patients (68%) had AIDS at WHO clinical stages 3 or 4. Patients with immunovirologic dissociation were more often in WHO clinical stages 3 and 4 (p = 0.0001). More than half of the cases (56.2%) were found to be malnourished and immunovirologic dissociation was prevalent in malnourished patients (p=0.005). The mean CD4+ T lymphocytes counts was 86.7± 83 cells / mm3. Immunovirologic dissociation was more frequent in patients with initial low CD4+ T lymphocyte counts and with a statistically significant difference (p = 0.00000). By multivariate analysis, only age greater than or equal to 43 years, CD4 initial counts &lt; 100 c/mm3 and male sex were significantly associated with this immunovirologic dissociation.Conclusion: our study assessed the main factors associated with immunovirologic dissociation. Other studies of this nature would also merit consideration in order to highlight the impact of this partial immune response on the emergence of opportunistic infections or the implementation of a specific tritherapy for the sole purpose of producing fully successful immune restoration.Keywords: Dissociation, immunovirologic, HIV, Daka
    corecore