DIFFICULTÉS DE LA PARTICIPATION EN RECHERCHE- ACTION : retour d'expériences de modélisation d'accompagnement en appui à l'aménagement du territoire au Sénégal et à la Réunion

International audienceComment aider les institutions et acteurs locaux à investir davantage les processus d'affectation des terres pour aménager leur territoire ? La décentralisation de l'aménagement du territoire engagée à la Réunion et au Sénégal est inachevée. Malgré l'arsenal législatif, les populations locales semblent peu impliquées dans les décisions les concernant en raison notamment de la difficulté à appréhender la complexité des systèmes d'interactions entre dynamiques sociales et environnementales. Le projet Domino vise à accompagner les processus de décision en proposant aux acteurs de construire et d'explorer des scenarii prospectifs d'affectation des terres. Cette expérience de modélisation participative repose sur une dynamique partenariale complexe sur chaque terrain, source de difficultés. Conscients des dérives potentielles, nous discutons la nécessité de construire une démarche qualité de notre recherche-action. Mots clés : montage de partenariat, démarche qualité, modèle, changement social, ComMod, interdisciplinarité, décentralisation, foncier, Sénégal, Réunio

Resistance to DDT and Pyrethroids and Increased kdr Mutation Frequency in An. gambiae after the Implementation of Permethrin-Treated Nets in Senegal

Introduction: The aim of this study was to evaluate the susceptibility to insecticides of An. gambiae mosquitoes sampled in Dielmo (Senegal), in 2010, 2 years after the implementation of Long Lasting Insecticide-treated Nets (LLINs) and to report the evolution of kdr mutation frequency from 2006 to 2010. Methods: WHO bioassay susceptibility tests to 6 insecticides were performed on adults F0, issuing from immature stages of An. gambiae s.l., sampled in August 2010. Species and molecular forms as well as the presence of L1014F and L1014S kd

The future of African nowcasting

Nowcasting (weather forecasting predictions from zero to several hours) has enormous value and potential in Africa, where populations and economic activity are highly vulnerable to rapidly changing weather conditions. Timely issuing of warnings, a few hours before an event, can enable the public and decision-makers to take action. Rainfall radar estimates are not widely available in Africa, nor likely to be in the coming years, and numerical weather prediction (NWP) currently has low skill over the African continent. Therefore, for the delivery of nowcasting in Africa, satellite products are the best practical option and needed urgently (Roberts et al., 2021). Fifteen minute (or faster) updates of MSG (Meteosat Second Generation) images and NWC-SAF (Nowcasting Satellite Applications Facility) products are crucial for nowcasting to warn users (e.g. fisherfolk on Lake Victoria, flooding in urban areas, etc.) on pending severe storms. The possibility to have such products every 10 minutes, as well as data from the forthcoming MTG (Meteosat Third Generation) lightning imager, would be highly beneficial to all African countries, saving lives and livelihoods where high population growth and the most extreme impacts of climate change combine

Heat transfer in a swirling fluidized bed with Geldart type-D particles

A relatively new variant in fluidized bed technology, designated as the swirling fluidized bed (SFB), was investigated for its heat transfer characteristics when operating with Geldart type D particles. Unlike conventional fluidized beds, the SFB imparts secondary swirling motion to the bed to enhance lateral mixing. Despite its excellent hydrodynamics, its heat transfer characteristics have not been reported in the published literature. Hence, two different sizes of spherical PVC particles (2.61mm and 3.65mm) with the presence of a center body in the bed have been studied at different velocities of the fluidizing gas. The wall-to-bed heat transfer coefficients were measured by affixing a thin constant foil heater on the bed wall. Thermocouples located at different heights on the foil show a decrease in the wall heat transfer coefficient with bed height. It was seen that only a discrete particle model which accounts for the conduction between the particle and the heat transfer surface and the gas-convective augmentation can adequately represent the mechanism of heat transfer in the swirling fluidized bed

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Les traumatisme du rachis cervical inferieur de c3-c7 a Niamey: aspects épidémiologiques, cliniques, paracliniques, évolutifs et pronostiques de cette affection: a propos de 20 cas: The inferior cervical spine trauma c3-c7 in Niamey: epidemiological, clinical, para clinical, progressive and prognostic aspects of the condition: a 20 cases study

Introduction : Les traumatismes du rachis cervical constituent une pathologie de plus en plus fréquente à la quelle doit faire face les médecins d’urgence et les neurochirurgiens ; du fait de la recrudescence des accidents de la voie publique et des chutes. Leurs gravités résident dans la possibilité d’atteinte médullaire immédiate ou secondaire pouvant engager le pronostic fonctionnel lors d’une tétraplégie complète et définitive; et/ou surtout vital en cas de troubles neurovégétatifs. Notre objectif est de définir les aspects épidémiologiques, cliniques, paracliniques, évolutifs et pronostiques de cette affection à Niamey au Niger.Patients et méthodes : Notre travail est une étude multicentrique, descriptive, à recueil prospectif et rétrospectif des données de 20 patients présentant un traumatisme du rachis cervical inférieur de C3 à C7, réalisée dans la communauté urbaine de Niamey de février 2011 à décembre 2018.Résultats : L’âge moyen de nos patients est de 35 ans, nous avons noté une prédominance masculine avec un sexe ratio de 5,66. Les étiologies sontdominées par les accidents de la voie publique (80%) suivis des accidents de sport (10%). Comme pratiquement dans tous les pays en voie de développement, les conditions de ramassage n’étaient pas précisées ni les premiers soins reçus sur place par les patients. Le délai moyen d’évacuation était de 24 heures avec des extrêmes d’une heure à 3 semaines sur une distance moyenne de 300 km pour 80% de nos patients. La durée du séjour de nos malades en hospitalisation était aussi très variable, elle est de 13 jours en moyenne avec des extrêmes de 1 à 47 jours. Sur le plan clinique, tous nos patients (100%) présentaient un syndrome rachidien variable dominé par des cervicalgies spontanées ou provoquées associés à des contractures de la nuque suivi ou pas de torticolis (25%) ou de névralgies cervico-brachiales (50%). Les patients présentaient aussi tous une symptomatologie médullaire avec des troubles médullo-radiculaires à des degrés divers ; c’est ainsi que nous avons 30% de tétraplégie complète, 20% de tétraplégie incomplète, 20% d’hémiplégie, 15% d’hémiparésie, 5% de monoparésie brachiale droite, 10% de diplégie brachiale, des troubles genitosphincteriens dans 30% des cas et des troubles neuro-végétatifs dans 10% des cas. Sur le plan des examens paracliniques, nous n’avions pratiqué dans aucun cas des radiographies standards du rachis cervical. 90% des patients avaient bénéficié d’un scanner et seulement 10% d’une IRM. On notait une nette prédominance des atteintes de la charnière vertébrale C6-C7 dans 45% des cas suivis des atteintes C5-C6 dans 30%, les atteintes de C4-C5 dans 15% et enfin les atteintes de C3-C4 dans 10% des cas. Les lésions sont de sévérité variables, les examens radiologiques ont révélé 30% de luxations pures, 25% de fracturesluxations, 20% de fractures simples, 10% de fractures comminutives, 10% de fractures tassement corporéales et 5% d’hernie discale post-traumatique. Le traitement médical était de règle, à base d’antalgique et/ou d’anti-inflammatoire non stéroïdien. Certains patients avaient bénéficié d’une corticothérapie courte durée par voie intraveineuse, d’autres ont aussi eu un traitement anticoagulant. Tous nos patients avaient aussi bénéficié d’un traitement orthopédique pur consistant en une immobilisation par une minerve type collier rigide sans traction crânienne. Le traitement chirurgical était réalisé par la voie d’abord antérieure chez 100% des patients. L’arthrodèse est suivie dans tous les cas d’une ostéosynthèse du foyer lésionnel par la pose d’une plaque vissée. Pour l’évolution clinique et radiologique à cours, moyen et long terme de nos patients elle est jugée favorable chez 50% des patients, il s’agit de 20% d’hémiplégie, 15% d’hémiparésie, 5% de monoparésie brachiale droite et 10% de diplégie brachiale. Par ailleurs elle est défavorable dans 25% des cas, il s’agit de 20% de tétraplégie incomplète et 5% d’hémiplégie complète. Enfin nous avons enregistré 25% de décès dans un délai de 2 à 21 jours. Les facteurs pronostics dépendent de la qualité et précocité de la prise en charge pré-hospitalière ; de l’état neurologique initial.Conclusion : Le traumatisme du rachis cervical est très fréquent et potentiellement grave par les conséquences fonctionnelles redoutables d’unelésion médullaire ; bien que les progrès de la réanimation, du nursing et de la rééducation aient diminué la mortalité. Cela justifie un bilan radiologique large mais adapté visant d’abord à limiter au maximum le risque de lésion passée inaperçue.ABSTRACTIntroduction: Cervical spine trauma is an increasingly frequent pathology which emergency physicians and neurosurgeons have to face. It is mostly due to the resurgence of accidents on the public highway and falls. Their seriousness lies in the possibility of immediate or secondary spinal cord injury which can initiate the functional prognosis during a full and final tetraplegia; and / or especially vital in the case of neuro vegetative disorders. Our objective is to define epidemiological, clinical, Para clinical, progressive and prognostic aspects of the condition in Niamey to Niger. Patients and methods: This is a multi-centric, descriptive, prospective and retrospective study of data from 20 patients with trauma to the lower cervical spine from C3 to C7, carried out in the urban community of Niamey from February 2011 to December 2018.Results: The average age of our patients is 35 years. We noted a male predominance with a sex ratio of 5.66. The etiologies are dominated by accidents on the public highway (80%) followed by sports accidents (10%). As in practically all the developing countries, the conditions of collection were not specified nor the first aid received on the spot by the patients. The average evacuation time was 24 hours with extremes of one hour to 3 weeks over an average distance of 300 km for 80% of our patients. The stay period of our patients in hospital was also very variable, it is 13 days on average with extremes from 1 to 47 days. Clinically, all of our patients (100%) had variable spinal syndrome dominated by spontaneous or induced neck pain associated with neck contractures followed or not by stiff neck (25%) or cervico-brachial neuralgia (50%). Also, all the patients presented spinal cord symptoms with medullary radicular disorders to varying degrees. Thus, we have 30% complete quadriplegia, 20% incomplete quadriplegia, 20% hemiplegia, 15% hemiparesis, 5% right brachial monoparesis, 10% brachial diplegia, genito-sphincter disorders 30% of cases and neuro-vegetative disorders 10% of cases. In terms of Para clinical examinations, we had in no case performed standard x-rays of the cervical spine. 90% of the patients had undergone a CT scan and only 10% of MRI. There was a clear predominance of attacks on the C6-C7 vertebral hinge in 45% of cases followed by C5-C6 attacks in 30%, C4-C5 attacks in 15% and finally C3-C4 attacks in 10% of case. The lesions are of varying severity, radiological examinations revealed 30% of pure dislocations, 25% of fractures dislocations, 20% of simple fractures, 10% of comminuted fractures, 10% of fractures of the body and 5% of post disc herniation - traumatic. Medical treatment was standard, based on analgesic and / or nonsteroidal antiinflammatory drugs. Some patients had received corticosteroids short route intravenously, the others have also had anticoagulant treatment. All patients had also gone through orthopedic pure treatment consisting of an immobilization by a brace-type rigid collar without skull traction. Surgical treatment was performed by the anterior approach in 100% of the patients. The arthrodesis is followed in all cases by an osteosynthesis of the lesion focus by the installation of a screwed plate. For changing clinical and radiological medium and long-term courses of our patients, it is considered favorable in 50% of patients, it is of 20% of hemiplegia, 15% hemiparesis, 5% of monoparesis brachial right and 10% brachial diplegia. In addition, it is unfavorable in 25% of cases, 20% of incomplete quadriplegia and 5% of complete hemiplegia. Finally, we recorded 25 % death from 2 to 21 days. Prognostic factors depend on the quality and earliness of pre- hospital care of the initial neurological state. Conclusion: Cervical spine trauma is very frequent and potentially serious due to the severe functional consequences of a spinal cord injury though advances in resuscitation, nursing, and rehabilitation have reduced mortality. This justifies a broad but appropriate radiological assessment aimed first at minimizing the risk of injury that has gone unnoticed

Difficultés de la participation en recherche-action : retour d'expériences de modélisation d'accompagnement en appui à l'aménagement du territoire au Sénégal et à la Réunion

How can scientists help institutions and local stakeholders be more involved in land use and territorial management processes? Decentralization of land use management is far from complete in Senegal and La Réunion Island. Despite exhaustive legislation, local populations remain little involved in the decisions that affect their land. This is partly due to the difficulties in understanding and managing the complexity of dynamic and interacting social and environmental systems. The Domino project aims at accompanying decision processes by proposing to stakeholders to build and explore scenarios of land use management. This experiment in participatory modelling, done on two contrasting sites, is built on complex partnership dynamics. In this paper we do a comparative analysis of difficulties raised by the involvement of partners in companion modelling. We conclude by discussing the need for quality process in action-research

Epilepsie refractaire secondaire generalisee revelatrice d’un meningiome frontobasal : a propos d’un cas clinique et revue de la litterature: Generalized secondary refractory epilepsy revealing fronto-basal meningioma: a clinical case study and literature review

Etaient considérés strictement comme répondant aux critères d’épilepsie réfractaire les patients ayant reçu au moins 2 antiépileptiques et suivis sur une durée d’au moins 24 mois. Les auteurs rapportent un cas d’épilepsie secondaire généralisée réfractaire révélatrice d’un méningiome fronto-basal. L’intérêt de notre observation réside surtout sur le caractère réfractaire de l’épilepsie qui ne cède pas malgré la chirurgie avec une revue de la littérature internationale. Le patient est toujours sous antiépileptiques 5 ans après le diagnostic et l’intervention chirurgicale. Le diagnostic est électro-clinique et scanographique. Un abord transcrânien a permis la cure complète du méningiome. L’évolution est favorable avec résolution à 80% des troubles épileptiques, une amélioration très sensible de la qualité de vie du patient.SUMMARYWere considered strictly as meeting the criteria for refractory epilepsy, patients having received at least two (2) antiepileptic drugs and followed for a period of at least 24 months. The authors report a case of generalized secondary refractory epilepsy indicative of a fronto-basal meningioma. The target of our observation lies above all in the refractory character of epilepsy, which still occurs despite surgery with international literature review. The patient is still on antiepileptic drugs 5 years after diagnosis and surgery. The diagnosis is electro-clinical and CT. A transcranial approach allowed the complete cure of the meningioma. The evolution is favorable with 80% resolution of seizure disorders, a very noticeable improvement in the patient's quality of life

Forme psychiatrique d’un meningiome geant ethmoïdo-frontal (fronto-basal) : a propos d’un cas et revue de la litterature internationale: Psychiatric form of a giant ethmoido- frontal meningioma (fronto-basal): a one case study and review of international litterature

Les méningiomes fronto-éthmoïdaux sont des méningiomes qui s’insèrent d’avant en arrière de l’apophyse crista-galli ou la totalité de la lame crible. En général ; ils sont bilatéraux, asymétriques, ils prédominent d’un cote et s’insinuent sous la faux du cerveau vers le cote opposé. D’évolution lente et silencieuse elles se révèlent le plus souvent par des complications neuropsychiatriques surtout, ophtalmologiques et olfactifs. Les auteurs rapportent un cas de méningiome géant ethmoïdo-frontal antérieur avec troubles psychiatriques, céphalées, baisse de l’acuité visuelle et anosmie. Le diagnostic est scanographique. Un abord transcrânien a permis la cure complète du méningiome. L’évolution est favorable avec résolution complète des troubles psychiatriques, une amélioration très sensible de la vision et une stabilisation de l’odorat. SUMMARYFronto-ethmoid meningiomas are meningiomas that insert back and forth of the crista-galli process or the entire cribriform plate. In general, they are bilateral, asymmetrical, and predominate on one side and creep under the scythe of the brain to the opposite side. Slow and silent, they are most often revealed by neuropsychiatric complications, especially ophthalmological and olfactory complications. Authors report a case of giant anterior ethmoidal frontal meningioma with psychiatric disorders, headache, reduced visual acuity and anosmia. The diagnosis is CT scan. A transcranial approach allowed the complete cure of the meningioma. The evolution is favorable with complete recovery of psychiatric functions, a very significant improvement in the visual and a stabilization of the sense of smell