269 research outputs found
Access to viral load monitoring for HIV infected patients on Antiretroviral Treatment in Decentralised area of low and middle income countries
No full textSur le plan mondial, le nombre de patients infectés par le VIH (PVVIH) sous traitement antirétroviral (TARV) est en constante augmentation. Les pays aux ressources limitées (PRL) sont les plus touchés par l’épidémie et de fortes inégalités existent ce malgré des objectifs ambitieux fixés par les Nations Unies en 2015 (90-90-90). Le suivi biologique nécessaire des patients sous TARV est connu et les avantages de la mesure de la charge virale (CV) sont bien établis en termes de détection précoce de l'échec thérapeutique, de détection de la non-observance au TARV et de prévention de l’accumulation de résistances. Cependant, dans les PRL et notamment en zone décentralisée, l’accès à la mesure de la CV reste très restreint. Les obstacles sont divers : difficulté d’accès pour les patients à un laboratoire en capacité d’effectuer cette mesure, manque en ressources humaines et matérielles. L’utilisation des Dried Blood Spot (DBS) comme support de prélèvement permet de surmonter ces barrières notamment du fait de sa simplicité, de l’absence de nécessité de chaine de froid et de l’utilisation des machines existantes.L’objectif de ce travail de thèse est de proposer et d’évaluer une stratégie afin d’améliorer le suivi virologique des PVVIH sous TARV issus de zones décentralisées de PRL en montrant la faisabilité et la validité d’un système de collecte de DBS afin de donner accès à la mesure de la CV aux patients suivis dans des centres non dotés des machines couteuses et de la logistique nécessaire à la réalisation de celle-ci. Une méta-analyse sur le contrôle virologique en Afrique Sub-saharienne a mis en évidence un taux de succès virologique en « intention de traiter » de 65.4% [61.8_69.1] et de 56.8% [51.3-62.4] à respectivement 12 et 24 mois de TARV ainsi qu’une proportion de succès significativement plus élevée rapportées dans les essais cliniques comparativement à ceux issus des cohortes. Ensuite, plusieurs projets ont été menés afin d’obtenir des résultats dans des conditions de vie réelle dans deux zones géographiques différentes: le Cameroun et le Vietnam. Au Cameroun, une étude menée dans 12 sites décentralisés a permis d’évaluer 2215 patients dont 937 ont été évalués virologiquement. Cette étude a montré un faible taux de rétention avec 63.3%, 53.5% et 39.9% à respectivement 12, 24 et 36 mois de l’initiation du TARV. Le taux de suppression virologique était très bas avec 66.6%, 62.7% et 59.8% à respectivement 12, 24 et 36 mois de TARV. Le profil des résistances virales analysé chez les patients ayant une CV>5000 cp/mL a montré une accumulation importante des résistances virales, s’aggravant au cours du temps et hypothéquant les options. Au Vietnam, deux études incluant 198 et 203 patients, ont été menées afin d’évaluer les performances de la mesure de la CV sur DBS comparativement au plasma. Trois techniques de mesure de la CV issues de deux industriels ont été évaluées. Une sensibilité de 93.3% [81.7–98.6], 90.1% [80.7-95.9] et 54.9% [40.3–68.9] a été trouvé avec respectivement l’ancien et le nouveau protocole fournis par Abbott et le nouveau protocole fourni par Roche (FVE). La spécificité retrouvé a été respectivement de 94.8% [90.0–97.7], 96.2% [91.4-98.8] et 100% [97.5–100]. Ainsi, à travers ces travaux nous avons montré que l’utilisation des DBS est faisable, immédiatement disponible et d’un niveau de performance acceptable. Elle permet d’apporter des données précieuses tant au niveau individuel, collectif que programmatique. L’utilisation des DBS devrait être intégrée à la stratégie d’expansion de l’accès à la CV. Le suivi virologique des patients est un enjeu de Santé Publique majeur dans un contexte d’utilisation en 1ère ligne de TARV de molécules à barrière génétique faible à la résistance, d’augmentation des résistances transmises et acquises et d’un taux d’incidence encore élevé de l’infection.Worldwide, the number of HIV-infected patients (PLWHA) on antiretroviral therapy (ART) is growing steadily. Low- and Middle-Incomes Countries (LMICs) are the most affected and strong inequalities still exist despite ambitious goals set by the United Nations in 2015 (90-90-90). The required biological monitoring of patients on ART is well known and the benefits of viral load (VL) measurement are well established, in terms of early detection of treatment failure, detection of non-adherence to ART and prevention of resistance accumulation. However, in LMICs and especially in decentralized areas, access to VL measurement remains scarce or unavailable. Barriers are various: difficulty for patients to reach a laboratory able to perform this measurement, lack of human and material resources. The use of Dried Blood Spot (DBS) as a sampling carrier allows to overcome these barriers, in particular because of its simplicity, the lack of the necessity of a cold chain and the use of existing machines. This PhD work aims at proposing and improving virological monitoring of PLWHA on ART living in decentralized areas of LMICs by demonstrating the feasibility and validity of a DBS collection system to provide access to VL measurement for patients followed in centres not equipped with costly machines and the logistics for its realization.A meta-analysis on virological success in Sub-Saharan Africa was conducted. This work showed a virological success rate in "intention to treat" analysis of 65.4%[61.8-69.1] and 56.8%[51.3-62.4] at 12 and 24 months of ART respectively, and a significantly higher proportion of success reported in clinical trials compared to cohorts. Then, several projects were conducted to obtain results in real life conditions in two different settings: Cameroon and Vietnam. In Cameroon, a study conducted in 12 decentralized sites evaluated 2215 PLWHA on ART, 937 of whom were virologically evaluated. This study showed a low retention rate with 63.3%, 53.5% and 39.9% at 12, 24 and 36 months after ART initiation, respectively. Virological suppression rate was also low with 66.6%, 62.7% and 59.8% at 12, 24 and 36 months of ART, respectively. Profiles of HIV Drug Resistance (HIVDR) in patients with VL>5000 cp/mL showed a significant accumulation of viral resistance, worsening over time and hypothecating therapeutic options. In Vietnam, two studies, involving 198 and 203 patients, were conducted to evaluate performance of VL measurement on DBS compared to plasma. Three VL techniques from two manufacturers were evaluated. Sensitivities of 93.3% [81.7-98.6], 90.1% [80.7-95.9] and 54.9% [40.3-68.9] were found with the old and optimized protocol provided by Abbott company and the new protocol provided by Roche company (FVE), respectively. Specificities were 94.8% [90.0-97.7], 96.2% [91.4-98.8] and 100% [97.5-100], respectively. Through this work, we showed that the use of DBS is feasible, immediately available and with an acceptable level of performance. It provides valuable data at the individual, collective and programmatic levels. The use of DBS should be integrated into the strategy of expanding access to VL. Virological monitoring of patients is a major public health challenge in a context of use in first line ART of molecules with a low genetic barrier to HIVDR, an increase of transmitted and acquired HIVDR and a persistently high incidence of infection
MODELISATION MARKOVIENNE DISCRETE ET CONTINUE D'UN PROCESSUS AUTOCORRELLE APPLICATION AU SUIVI DE PATIENTS VIH POSITIFS
No full textLA MODELISATION DE L'EVOLUTION D'UNE MALADIE AU COURS DU TEMPS PEUT SE FAIRE A L'AIDE D'UN MARQUEUR BIOLOGIQUE, UTILISE COMME INDICATEUR DE L'ETAT DE SANTE. LORSQUE LE MARQUEUR BIOLOGIQUE EST UNE VARIABLE A SUPPORT CONTINU, DEUX APPROCHES PEUVENT ETRE ENVISAGEES : UNE APPROCHE CONTINUE QUI MODELISE DIRECTEMENT LE MARQUEUR PAR UN PROCESSUS A ESPACE D'ETATS CONTINU, UNE APPROCHE DISCRETE QUI MODELISE LA PROGRESSION DE LA MALADIE PAR UN PROCESSUS A ESPACE D'ETATS DISCRET, LES VALEURS DE CE PROCESSUS ETANT OBTENUES PAR DISCRETISATION DU MARQUEUR CONTINU. L'OBJECTIF DE CETTE THESE EST DE COMPARER CES DEUX APPROCHES POUR MODELISER L'EVOLUTION D'UN PROCESSUS CONTINU DANS UN CADRE MARKOVIEN. AFIN D'OBTENIR UN MODELE CONTINU POUVANT ETRE UTILISE COMME REFERENCE, CE TRAVAIL EST BASE SUR DES DONNEES SIMULEES. LE MODELE DE SIMULATION REPRODUIT LES CARACTERISTIQUES D'UN PROCESSUS BIOLOGIQUE : FONCTION DEPENDANTE DU TEMPS ET STRUCTURE D'AUTOCORRELATION ENTRE LES RELEVES D'UN INDIVIDU. DEUX MODELES D'ESTIMATION CONTINUS SONT MIS EN PLACE. LE PREMIER MODELE, IDENTIQUE AU MODELE DE SIMULATION, FAIT L'HYPOTHESE QUE LA DATE D'ORIGINE DU PROCESSUS EST CONNUE. LE SECOND MODELE CONTINU (A EFFETS MIXTES) FAIT L'HYPOTHESE QUE LA DATE D'ORIGINE EST INCONNUE. DEUX MODELES DISCRETS (MODELES MULTI-ETATS) PERMETTENT EGALEMENT DE CARACTERISER LA PROGRESSION DU MARQUEUR. UN MODELE N'AUTORISE QUE LES PASSAGES VERS UN ETAT REPRESENTANT UNE GRAVITE SUPERIEURE, ET UN MODELE AUTORISE LES RETOURS VERS L'ETAT DE GRAVITE PRECEDANT. LA COMPARAISON DES APPROCHES CONTINUES ET DISCRETES EST BASEE SUR TROIS ASPECTS. L'ESTIMATION DE LA DISTRIBUTION DU TEMPS DE PASSAGE VERS UNE VALEUR FIXEE DU MARQUEUR PERMET D'ETUDIER LA PROGRESSION DU MARQUEUR BIOLOGIQUE. L'ECART QUADRATIQUE MOYEN ENTRE LES VALEURS DU MARQUEUR ET LEURS PREDICTIONS PERMET DE JUGER DE LA CAPACITE DES MODELES A PREDIRE A COURT TERME. LE TROISIEME ASPECT DE LA COMPARAISON EST BASE SUR LES PREDICTIONS A LONG TERME. LES DIFFERENTES MODELISATIONS SONT ENSUITE APPLIQUEES A DES DONNEES REELLES ISSUES DE LA COHORTE CONCORDE CORRESPONDANT AU SUIVI DE 1638 PATIENTS SEROPOSITIFS SOUS DIFFERENTS PROTOCOLES DE TRAITEMENT. LES OUTILS DE COMPARAISON SONT EGALEMENT APPLIQUES A CES MODELES.PARIS5-BU Saints-Pères (751062109) / SudocSudocFranceF
First passage time problem for a drifted Ornstein–Uhlenbeck process
No full textInternational audienc
Fundamentals of Material Design Culture
No full textThis essay is published in the book Ideas and the Matter, edited by Marinella Ferrara and Giulio Ceppi. The book presents the founding research undertaken by the Politecnico di Milano’s Material Design Culture Research Centre (Madec). Founded in 2014, Madec obtained the Design Department’s support during its first year by being granted the Fondo di Ateneo per la Ricerca di Base (FARB 2013) for “Fundamental/Foundational/ Exploratory Researches that are strategically assessed for scientific growth in a research department”. In the third section of the book, scientific discourse focuses on the Material Design Culture and changing approach in term of the evolution of research methods. In the chapter "Fundamental of Material Design Culture", the author traces the fundamentals of Material Design based on the Italian design history and its relationship with global design discourse
Shifting to Design-driven Material Innovation
No full textThis essay is published in the book Ideas and the Matter, edited by Marinella Ferrara and Giulio Ceppi. The book presents the founding research undertaken by the Politecnico di Milano’s Material Design Culture Research Centre (Madec). Founded in 2014, Madec obtained the Design Department’s support during its first year by being granted the Fondo di Ateneo per la Ricerca di Base (FARB 2013) for “Fundamental/Foundational/ Exploratory Researches that are strategically assessed for scientific growth in a research department”. In the third section of the book, scientific discourse focuses on the Material Design Culture and changing approach in term of the evolution of research methods. In this chapter, the author analyses several changes in the design discipline and in the approaches to Material design and explores the new dimension of the contemporary trend of material innovation driven by design competences
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Understanding 1968: the case of Brest
No full textThis article examines the dominance of Paris in how May '68 has been portrayed over the years. It will be argued, through a case-study of the revolt in the Breton city of Brest, that the Paris-centred approach is one that belies the true nationwide aspect of May/June 1968. As one of a range of characteristics, the concentration on the Latin Quarter has helped mould what Kristin Ross has described as the 'official history' of 1968. An examination of how the events were played out within different regional contexts would go a long way towards helping overcome the shortcomings of the increasingly narrow portrayal that has come to dominate the stereotypical image of 1968
Modelo de gestión financiera para la empresa de materiales y acabados de la construcción MADEC de la ciudad de Ibarra, provincia de Imbabura
No full textEl objetivo principal de la investigación: MODELO DE GESTIÓN FINANCIERA PARA LA EMPRESA DE MATERIALES Y ACABADOS DE LA CONSTRUCCIÓN MADEC, DE LA CIUDAD DE IBARRA, PROVINCIA DE IMBABURA fue diseñar un modelo de gestión financiera, a través de procesos y políticas para el cuidado de los recursos financieros de esta organización; por consiguiente, fue determinante una revisión bibliográfica y el establecimiento de la situación actual de ella, para con esto, realizar un planteamiento aplicable acorde a las necesidades de esta entidad. Por su parte, el documento fue estructurado de la siguiente manera: Capítulo I, contiene un marco teórico que sirvió de sustento científico y dio horizonte al trabajo basado en una temática necesaria para la consecución de la meta antes expuesta; es importante mencionar que, su estructura fue basada en una metodología inductiva y que se respetó los lineamientos y normativas de la Universidad en cuento a la presentación de documentos formales y citas de autor. En el Capítulo II se realizó un diagnóstico de la situación referente al modelo de gestión financiera que la empresa de materiales y Acabados para la Construcción efectúa; es menester acotar que esto fue posible gracias a la información recolectada mediante instrumentos como encuestas a los trabajadores del área financiera y entrevistas a los directivos, en este contexto, se logró establecer los principales aspectos referidos a este tipo de diligencia. En el Capítulo III, se diseñó la propuesta, en base a un direccionamiento estratégico, además el estructural, funciones para el talento humano, flujogramas de los procesos requeridos y políticas que coadyuven a las diversas actividades; finalmente, conclusiones y recomendaciones.The main objective of the investigation: MODEL OF FINANCIAL MANAGEMENT FOR THE COMPANY OF MATERIALS AND FINISHES OF THE CONSTRUCTION MADEC , OF THE CITY OF IBARRA, PROVINCE OF IMBABURA was to design a model of financial management, through processes and policies for the care of the financial resources of this organization; therefore, a bibliographic review and the establishment of the current situation of it was decisive, in order to make an applicable approach according to the needs of this entity. For its part, the document was structured as follows: Chapter I, contains a theoretical framework that served as scientific support and gave scope to work based on a theme necessary for the achievement of the above-stated goal; It is important to mention that its structure was based on an inductive methodology and that the guidelines and regulations of the University were respected in relation to the presentation of formal documents and author citations. In Chapter II, a diagnosis was made of the situation regarding the financial management model that the company of materials and Finishes for Construction makes; It is necessary to note that this was possible thanks to the information collected through instruments such as surveys of workers in the financial area and interviews with managers, in this context, it was possible to establish the main aspects related to this type of diligence. In Chapter III, the proposal was designed, based on a strategic direction, in addition to the structural, functions for human talent, flowcharts of the required processes and policies that contribute to the various activities; finally, conclusions and recommendations
Modelo de gestión financiera para la empresa de materiales y acabados de la construcción MADEC de la ciudad de Ibarra, provincia de Imbabura
No full textEl objetivo principal de la investigación: MODELO DE GESTIÓN FINANCIERA PARA LA EMPRESA DE MATERIALES Y ACABADOS DE LA CONSTRUCCIÓN MADEC, DE LA CIUDAD DE IBARRA, PROVINCIA DE IMBABURA fue diseñar un modelo de gestión financiera, a través de procesos y políticas para el cuidado de los recursos financieros de esta organización; por consiguiente, fue determinante una revisión bibliográfica y el establecimiento de la situación actual de ella, para con esto, realizar un planteamiento aplicable acorde a las necesidades de esta entidad. Por su parte, el documento fue estructurado de la siguiente manera: Capítulo I, contiene un marco teórico que sirvió de sustento científico y dio horizonte al trabajo basado en una temática necesaria para la consecución de la meta antes expuesta; es importante mencionar que, su estructura fue basada en una metodología inductiva y que se respetó los lineamientos y normativas de la Universidad en cuento a la presentación de documentos formales y citas de autor. En el Capítulo II se realizó un diagnóstico de la situación referente al modelo de gestión financiera que la empresa de materiales y Acabados para la Construcción efectúa; es menester acotar que esto fue posible gracias a la información recolectada mediante instrumentos como encuestas a los trabajadores del área financiera y entrevistas a los directivos, en este contexto, se logró establecer los principales aspectos referidos a este tipo de diligencia. En el Capítulo III, se diseñó la propuesta, en base a un direccionamiento estratégico, además el estructural, funciones para el talento humano, flujogramas de los procesos requeridos y políticas que coadyuven a las diversas actividades; finalmente, conclusiones y recomendaciones.The main objective of the investigation: MODEL OF FINANCIAL MANAGEMENT FOR THE COMPANY OF MATERIALS AND FINISHES OF THE CONSTRUCTION MADEC , OF THE CITY OF IBARRA, PROVINCE OF IMBABURA was to design a model of financial management, through processes and policies for the care of the financial resources of this organization; therefore, a bibliographic review and the establishment of the current situation of it was decisive, in order to make an applicable approach according to the needs of this entity. For its part, the document was structured as follows: Chapter I, contains a theoretical framework that served as scientific support and gave scope to work based on a theme necessary for the achievement of the above-stated goal; It is important to mention that its structure was based on an inductive methodology and that the guidelines and regulations of the University were respected in relation to the presentation of formal documents and author citations. In Chapter II, a diagnosis was made of the situation regarding the financial management model that the company of materials and Finishes for Construction makes; It is necessary to note that this was possible thanks to the information collected through instruments such as surveys of workers in the financial area and interviews with managers, in this context, it was possible to establish the main aspects related to this type of diligence. In Chapter III, the proposal was designed, based on a strategic direction, in addition to the structural, functions for human talent, flowcharts of the required processes and policies that contribute to the various activities; finally, conclusions and recommendations
First evaluation of bendiocarb in experimental huts using different substrates in Madagascar
No full textInternational audienceBACKGROUND:Indoor residual spraying with insecticide is recommended for malaria control in high-transmission settings. Determination of residual activity of insecticides is essential for the selection of appropriate indoor spraying policy. The present study was undertaken to evaluate the residual effect of bendiocarb, a carbamate insecticide used in Madagascar, on different indoor surfaces in order to elaborate future vector control interventions.METHODS:The residual activity of bendiocarb was evaluated in both experimental huts and houses. Tests in experimental huts on different substrates represented a small scale-field trials. The houses IRS performed in parallel of experimental huts IRS, was done to compare semi-field results and field results. Bioassays according to the World Health Organization (WHO) standard protocol were carried out on different substrates impregnated with bendiocarb using susceptible strains of Anopheles arabiensis and Aedes albopictus.RESULTS:Bendiocarb induced significantly high mortality in treated huts against exposed mosquito (p < 0.005) compared to untreated huts. The mortality is up to the WHO threshold of 80 % during 5 months post-treatment. Using a multivariate analysis, Ae. albopictus mortality decreased significantly from the 3rd month post-treatment. However, An. arabiensis mortality decreased significantly from the 4th month after treatment. Comparing mosquito mortality results from the mud experimental huts and the mud houses showed no significant difference regarding the persistence of bendiocarb on wall.CONCLUSIONS:Current data suggest variable persistence of bendiocarb according to the type of wall surfaces, highlighting the importance of testing insecticide for IRS in local context before using them in large scale. Data from this study validate also the importance of using experimental huts as representative tool to evaluate the effectiveness of an insecticide
Differential responses of the mosquito Aedes albopictus from the Indian Ocean region to two chikungunya isolates
No full textInternational audienceBACKGROUND: Aedes aegypti and Aedes albopictus are both vectors of chikungunya virus (CHIKV). The two Aedes species co-exist in the Indian Ocean region and were involved in the 2005-2006 CHIKV outbreaks. In the Reunion Island, a single mutation in the viral envelope has been selected that leads to high levels of replication in Ae. albopictus, and a short extrinsic incubation period as the virus could be found in saliva as early as two days after infection. An important question is whether this variant is associated with adverse effects impacting some mosquito life-history traits such as survival and reproduction. RESULTS: We performed experimental infections using three mosquito strains of Ae. aegypti Mayotte and Ae. albopictus (Mayotte and Reunion), and two CHIKV strains (E1-226A and E1-226V). Ae. aegypti Mayotte were similarly susceptible to both viral strains, whereas Ae. albopictus Mayotte and Ae. albopictus Reunion were more susceptible to CHIKV E1-226V than to E1-226A. In terms of life-history traits measured by examining mosquito survival and reproduction, we found that: (1) differences were observed between responses of mosquito species to the two viruses, (2) CHIKV infection only affected significantly some life-history traits of Ae. albopictus Reunion and not of the other two mosquito strains, and (3) CHIKV reduced the lifespan of Ae. albopictus Reunion and shortened the time before egg laying. CONCLUSION: We demonstrated that CHIKV only reduces the survival of Ae. albopictus from the Reunion Island. By laying eggs just before death, reproduction of Ae. albopictus from the Reunion Island is not reduced since other parameters characterizing oviposition and hatching were not affected
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