Barcoding: Comparison of Variation Degree of COI and Cytochrome b Mitochondrial Markers in Two Species Primary Maize Pests (Sitophilus zeamais and Sitophilus oryzae)

The phylogeny, taxonomy and identification of insects were originally based upon shared or derived morphological and anatomy criteria. However, these processes are confronted with the barrier of the existence of sympatric or cryptic species. Thus, genetic analyses have more recently played an increasingly important role in confirming existing or establishing often radically different insect

Incidence and determinants of new AIDS-defining illnesses after HAART initiation in a Senegalese cohort

<p>Abstract</p> <p>Background</p> <p>Although a dramatic decrease in AIDS progression has been observed after Highly Active Anti Retroviral Therapy (HAART) in both low- and high-resource settings, few data support that fact in low-resource settings.</p> <p>This study describes the incidence of AIDS-defining illnesses (ADI) after HAART initiation and analyzes their risk factors in a low-resource setting. A focus was put on CD4 cell counts and viral load measurements.</p> <p>Methods</p> <p>404 HIV-1-infected Senegalese adult patients were enrolled in a prospective observational cohort and data censored as of April 2008. A Poisson regression was used to model the incidence of ADIs over two periods and to assess its association with baseline variables, current CD4, current viral load, CD4 response, and virological response.</p> <p>Results</p> <p>ADI incidence declined from 20.5 ADIs per 100 person-years, 95% CI = [16.3;25.8] during the first year to 4.3, 95% CI = [2.3;8.1] during the fourth year but increased afterwards. Before 42 months, the decrease was greater in patients with clinical stage CDC-C at baseline and with a viral load remaining below 1000 cp/mL but was uniform across CD4 strata (p = 0.1). After 42 months, 293 patients were still at risk. The current CD4 and viral load were associated with ADI incidence (decrease of 21% per 50 CD4/mm³and of 61% for patients with a viral load < 1000 cp/mL).</p> <p>Conclusions</p> <p>During the first four years, a uniform decline of ADI incidence was observed even in patients with low CD4-cell counts at HAART initiation as long as the viral load remained undetectable. An increase was noted later in patients with immunologic and virological failures but also in patients with only virological failure.</p

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

Alliages réfractaires à microstructure contrôlée

The aim of this thesis was to address certain challenges concerning the mass production of tungsten nanopowders (W) and tungsten alloys (W-V-Cr and W-V), but also the study of their mechanical properties (ductility, yield strength) and their resistance to recrystallization after sintering, with a view to their use as a plasma-facing material in the ITER project. For mass production, syntheses of W nanopowders and W alloys were made from the combustion synthesis process, Self-propagating High-temperature Synthesis (SHS). Batch syntheses of between 50 and 500 g of powders were carried out at two temperatures (1800K and 2500K) in order to meet all the challenges relating to the scaling of this SHS process. These powders after characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM) and dynamic light scattering (DLS) showed nanometric particles and a fairly similar microstructure (before and after scaling). As a result, the study of the mechanical properties (ductility and microhardness) and the resistance to recrystallization was carried out on blocks obtained after sintering by Spark Plasma Sintering (SPS). These characterizations have shown that W-V binary alloys have better ductility compared to pure W and ternary alloy WV2Cr2. In fact, a ductility of almost 37.5% was obtained during the compression test at ambient temperature of the W-V8 alloy. All the samples showed good resistance to recrystallization at 1000° C. for 1 h.  These results are promising for use as materials of the divertor. However, it is necessary to supplement this with other characterizations such as the study of resistance to oxidation at high temperature, the study of thermal shocks, etc.Cette thèse a été menée dans le but de répondre à certains défis concernant la production en masse de nanopoudres de tungstène (W) et d'alliages de tungstène (W-V-Cr et W-V), mais également l'étude de leurs propriétés mécaniques (ductilité, limite élastique) et de leur résistance à la recristallisation après frittage, en perspective à une utilisation comme matériau face au plasma dans le cadre du projet ITER. Concernant la production en masse, les synthèses de nanopoudres de W et d'alliages de W ont été faites à partir du procédé de synthèse par combustion, Self-propagating High-temperature Synthesis (SHS). Des synthèses de lots compris entre 50 et 500 g de poudres ont été effectuées à deux températures (1800K et 2500K) afin de répondre à tous les défis relatifs à la mise en échelle de ce procédé SHS. Ces poudres après caractérisations par Diffraction des rayons X, par microscopie électronique à balayage et Dynamic Light Scattering (DLS) ont montré des particules nanométriques et une microstructure assez similaire (avant et après mise en échelle). A suite de cela, l'étude des propriétés mécaniques (ductilité et microdureté) et de la résistance à la recristallisation a été menée sur des massifs obtenus après frittage par Spark Plasma Sintering (SPS). Ces caractérisations ont montré que les alliages binaires W-V présentent une meilleure ductilité par rapport au W pur et à l'alliage ternaire WV2Cr2. En effet, une ductilité de près de 37,5% a été obtenue lors de l'essai de compression à température ambiante de l'alliage W-V8. L'ensemble des échantillons ont présenté une bonne résistance à la recristallisation à 1000°C pendant 1h.  Ces résultats sont prometteurs pour une utilisation comme matériaux du divertor. Néanmoins, il est nécessaire de compléter par d'autres caractérisations comme l'étude de la résistance à l'oxydation à haute température, l'étude des chocs thermiques, etc

Bien utiliser le français et le matériel didactique pour mieux enseigner les mathématiques

info:eu-repo/semantics/published

Systeme de sport-etudes au Senegal, entre performance et reconversion: Sport-study system in Senegal, in search of performance and good retirement

Le Sénégal a du mal à produire des sportifs d’élite et à jouer les grands rôles sur la scène internationale. Cette situation s’explique par le fait que les jeunes talents sénégalais sont obligés dans leur grande majorité à choisir entre le sport et les études à cause de l’absence d’un système qui permet de concilier le sport et les études. Les expériences vécues par beaucoup d'athlètes sénégalais (exemple Kène Ndoye médaillée de bronze aux championnats du monde au triple saut à Birmingham en 2003, de Bocandé ancien capitaine du Sénégal) et étrangers (exemple Emmanuel Eboué ancien international ivoirien) ont poussé les auteurs à se pencher sur la question de la retraite des sportifs. Ledit système devrait être adapté aux réalités socioéconomiques, psychosociales et historiques du Sénégal. Ainsi, 298 sportifs d’élite dont 113 à la retraite et 185 en activité ont été enquêtés, en plus des quatre experts choisis selon des critères bien définis. Cela nous a permis de confirmer sur le plan qualitatif les données quantitatives obtenues dans un premier temps. Le paradigme de recherche utilisé est le Devis Mixte Séquentiel Explicatif. Nous nous sommes basés sur les aspects historiques liés à la psychologie du sport et au système de Sport-Études, avant d’évoquer les résultats obtenus dans les pays qui ont mis en application ledit système depuis l’arrivée de l’URSS sur la scène internationale en 1952 à nos jours. Au vu des résultats obtenus, nous avons proposé un de système de Sport-Études adapté au contexte sénégalais.ABSTRACTSenegal has hard time producing Elite sport’s men and playing key roles at an international level. This situation could be explained by the fact that young talented Senegalese are obliged in a big majority to choose between sports and studies, because of a lack of a system offering the possibility to do both at the same time. As a result of that situation, a lots of former elite athletes live in very difficult conditions at the end of their career. The way former athletes end they lives in Senegal (for example Kene Ndoye winner of bronze medal at word championship at Birmingham in 2003 and Jules Bocandé former captain of senegale's soccer team) and Africa (Emmanuel Eboué former Ivory Cost national team and Arsenal player) inspired the authors about setting a sport-study system to enable the double project. That system would have to take into account the sociological, psychological and historical aspects of sports in Senegal. For that, 298 elite sportsmen have been called in our survey. Among them we have 113 retired and 185 that are still active in competition. For the type of investigation, the explanatory sequential mixed methods have been used. We have talked about the Olympics because of his link with high performance. We have also talked about sport psychology and the history of the academies in charge of Sport-Studies in the world since the coming of URSS in 1952 until today. This investigation was ended with a proposal of a Sport-Study system

Epidemiologic and clinicopathologic aspects of Leprosy in Dakar; evaluation of 73 new cases

Hundreds of new leprosy cases are still diagnosed in Dakar despite all the efforts in the struggle by the national program for elimination of leprosy by the Institute of Applied Leprosy in Dakar. The aim of our study was to evaluate the epidemiological, clinicopathological and outcome of new cases of leprosy. A prospective study was conducted over a period of one year listing all new cases of leprosy based on clinical diagnosis, bacteriology and histology. 73 new cases were recorded. The sex ratio was 1.5 and the mean age of 39.5 years. Children aged from 0 to 15 years old represented 12%. The clinical forms were rated in order of decreasing frequency Borderline 47.94%, 30.13% lepromatous lepromatous, indeterminate 8.21, borderline lepromatous 6.84, TT: 5.47%, 1.36 and neurological bb%. Neurological signs were enlarged nerve in 50 cases, a neurological deficit in 16 cases and a sensitive deficit in 16 cases. The complications were burns and ulcerations in 10 cases, a claw in 7 cases, a reversal reaction in 7 cases, erythema nodosum in 4 cases and neuritis in 8 cases. The number of new cases mutilated was 24.65%. The smear was positive in 42% and histology contribution in 91.37% of cases. Our study highlights the significant number of patients with multibacillary contagious, affected children, the high proportion of disability grade 2/OMS reflecting the delay in diagnosis. This delay is due to ignorance, to traditional treatments and low socio-economic status and lack of trained diagnostic teams in different areas apart from referral centres

The characteristics of severe forms of psoriasis on pigmented skins: A retrospective study of 102 cases in Dakar, Senagal

Background: Severe forms of psoriasis can be life-threatening for patients. Our objective was to determine the epidemiological, clinical, therapeutic aspects and outcome of severe forms of psoriasis. Methodology: A 18 years retrospective study conducted in the department of Dermatology at Le Dantec hospital listed all the severe forms of psoriasis. Results: We have collected 102 cases of severe forms. The sex ratio was 1.55 and the average age of 47 years. The family histories of psoriasis were reported in 5 patients. Arterial hypertension was noted in 10 patients, diabetes in 4 patients and obesity in 6 patients. Smoking and alcoholism were found respectively in 10 cases and 7 cases. The average duration of the lesions was 2 years. Phytotherapy was reported in 62 patients (62%). Pruritus was present in 86 patients (84%). The clinical forms of psoriasis were: erythroderma in 76 cases (74.5%), psoriatic arthritis in 14 cases (13.7%) and a pustular form in 12 cases (11%). HIV serology was positive in 12 patients. All patients had received a treatment with topical corticosteroids and emollients. Methotrexate was initiated in 57 patients and retinoids in 27 cases. The outcome was favorable in 67 patients (65%). We recorded 6 deaths (6%). Conclusion: The large use of oral phytotherapy medicines and inappropriate treatment precipitated or speeded up the occurrence of severe forms of psoriasis among our patients