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Hydrogen-based direct reduced iron (H2-DRI) is an alternative pathway for low-carbon steel production. Yet, the lack of established process and business models defining “green steel” makes it difficult to understand what the respective H2 price has to be in order to be competitive with commercial state-of-the-art natural gas DRI. Given the importance of establishing break-even H2 prices and CO2 emission reduction potentials of H2-DRI, this study conducted techno-economic analyses of several design and operation scenarios for DRI systems. Results show that renewable H2 use in integrated DRI steel mills for both heating and the reduction of iron ore can reduce direct CO2 emissions by as much as 85%, but would require an H2 procurement cost of $1.63 per kg H2 or less. When using H2 only for iron ore reduction, economic viability is reached at an H2 procurement cost of $1.70 per kg, while achieving a CO2 emission reduction of 76% at the plant site. System design optimization strategies around excess H2 ratios in the DRI top gas and the H2 recycle pressurization can further improve performance and economics. Low H2 excess ratios are particularly attractive as they reduce pre-heating energy requirements and offer integration opportunities with static recycle ejectors if H2 is supplied at sufficiently high pressure. The potential of utilizing the electric arc furnace off-gas is shown to be much more synergistic with H2-DRI than natural gas-DRI and can increase the break-even H2 procurement cost by up to 7¢ per kg H2. Such findings are critical for setting technical performance criteria for H2 supply and storage in the iron and steel sector.

Résumé: Alors que le décadentisme bat en brèche les vestiges du Naturalisme, Edouard Dujardin publie Les lauriers sont coupés, véritable roman d'expression d'un lyrisme que l'on pourrait qualifier d'iconoclaste à la fin du XIXe siècle. Dans un style typiquement romantique, il réactualise les bases du monologue intérieur et se présente comme le réformateur de cette forme scripturale. Ce désir ardent de rompre avec le statique, semble être le dessein de cette œuvre aux multiples relents scripturaux qui opère sous l'œil du personnage-narrateur. Derrière cet œil, la figure de l'auteur dessine comme une sorte d'effacement énonciatif pour reprendre les propos d'Alain Rabatel. La présente étude vise ainsi à examiner le mode opératoire de l'élaboration de la diégèse sous le prisme du double point de vue du narrateur et de l'auteur. Autrement dit, comment fonctionne la voix auctoriale sous l'emprise du jeu de la fiction que suggère le genre ? La linguistique énonciative constitue la méthode d'analyse des Lauriers sont coupés pour en ressortir l'esthétique dujardinienne, du moins, pour ce qui est du monologue intérieur. Mots-clés : Décadence, Ecriture de soi, Monologue intérieur, Subjectivité.

Chikungunya virus has caused millions of cases worldwide over the past 20 years, with recent outbreaks in Kedougou region in the southeastern Senegal, West Africa. Genomic characterization highlights that an ongoing epidemic in Kedougou in 2023 is not due to an introduction event but caused by the re-emergence of an endemic strain evolving linearly in a sylvatic context.

In this interview, originally recorded in person, Samuel "Sammy" Yoro speaks with Watsonville is in the Heart team member, Hana Yamamoto. Sammy begins by discussing how his father, Sabino Ivanos Yoro came to the United States from the Philippines and eventually settled in Watsonville to work in the lettuce fields. Sammy talks about how he began working with his father harvesting produce in high school and he describes how working in the asparagus fields helped him become a better track and field athlete in high school. Sammy goes on to describe how the agriculture industry evolved over the years and notes the influence of Cesar Chavez on farm labor strikes. Sammy discusses his involvement with The Independent Farmworkers Union. Sammy also talks about his mother, Gregor Otero, who came to Watsonville from New Mexico to start a family and work in the canneries. Sammy reflects on how growing up in a multiracial community affected his views on his parents' interracial marriage, and he remembers his mother's involvement in Filipino community organizations.

In this study, some selected clay samples were beneficiated and blended with quartz and feldspar in various proportions to develop composites with good thermal and structural performance for sustainable development. X-ray fluorescence (XRF) analysis affirms the aluminosilicate nature of the clay samples and other trace oxides. The pore volume of the fired bulk composites disappears at 1200 °C leading to a decline in apparent density, apparent porosity, and water absorption. Furthermore, this study revealed that at the same temperature, the bulk density (1.69, g/cm3, 1.78, g/cm3, 1.78 g/cm3), modulus of rupture (33.2 kg/cm3, 39.34 kg/cm3, 38.88 kg/cm3), and total shrinkage (23.6 %, 22.3 %, 20.6 %) were maximum. Additionally, the results showed that the relative plasticity of the clay samples improved with the addition of feldspar and quartz from 1.27 to 1.33 and 1.35 for the fired composites (BO1: 50 % clay, 30 % feldspar, 20 % quartz, and CO1: 50 % clay, 25 % feldspar, 25 % quartz), respectively. Results obtained from thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) analysis confirmed the clay samples to be thermally stable. The X-ray diffraction (XRD) patterns of all the fired composites showed major peaks, with quartz content being the highest at 27.5° (2θ) angle, albite presenting the lowest non-clay mineral content. Based on the analyses conducted in this study, it could be inferred that the clay sample is suitable for thermal insulation and structural applications.

Crimean-Congo hemorrhagic fever (CCHF), a severe form of hemorrhagic fever primarily transmitted to humans and animals through tick bites, is caused by CCHF virus (CCHFV). In addition, direct human contact [...]

This study investigates the effect of zeolite nano-catalyst on the yield of biodiesel and biochar formed from the pyrolysis of tallow (cow fat). Residual waste cow fat was pyrolyzed in a fixed-bed reactor of laboratory-scale volume 2200 cm3, at operating temperatures of 450, 500, 530, and 580 °C and heating rates of 4, 5, and 6 °C/min. The molecular composition of cow fat was analyzed using a gas chromatography molecular spectrograph (GC-MS). It was observed that the biodiesel produced without a catalyst was mainly composed of aromatic carboxylic acids, esters, alkanes, alkenes, and alkanes, while the biodiesel produced with zeolite nano-catalyst consisted mainly of methyl esters, pentanoic acid, heptanoic acid, cyclo-olefins, 4,4-dimethylcyclohexene, butyl-cyclohexane, butyl-cyclopentane, and 1-pentylcyclopentene. A biodiesel yield of 58% was achieved when a 1% zeolite nano-catalyst was used to pyrolyze the tallow at an operating temperature of 530 °C and heating rate of 6 °C/min. When the tallow was pyrolyzed without a zeolitic catalyst, decarboxylation was promoted, and a higher biodiesel yield of 82.78 wt% was achieved. Results from this study revealed that although zeolite nano-catalyst did not show an incremental effect on the yield of biodiesel, it favors biogas production and biochar formation.

Abstract Background Land plants exhibit a haplodiplontic life cycle, whereby multicellular bodies develop in both the haploid and diploid generations. The early-diverging land plants, known as bryophytes, have a haploid-dominant life cycle, in which a short-lived multicellular body in the diploid generation, known as the sporophyte, develops on the maternal haploid gametophyte tissues. The moss Physcomitrium (Physcomitrella) patens has become one of the most powerful model systems in evolutionary plant developmental studies. To induce diploid sporophytes of P. patens, several protocols are implemented. One of the conventional approaches is to grow approximately one-month-old gametophores for another month on Jiffy-7 pellets made from the peat moss that is difficult to fully sterilize. A more efficient method to obtain all tissues throughout the life cycle should accelerate studies of P. patens. Results Here, we investigated the effect of nitrogen conditions on the growth and development of P. patens. We provide an improved protocol for the sporophyte induction of P. patens using a BCD-based solid culture medium without Jiffy-7 pellets, based on the finding that the formation of gametangia and subsequent sporophytes is promoted by nitrogen-free growth conditions. The protocol consists of two steps; first, culture the protonemata and gametophores on nitrogen-rich medium under continuous light at 25 °C, and then transfer the gametophores onto nitrogen-free medium under short-day and at 15 °C for sporophyte induction. The protocol enables to shorten the induction period and reduce the culture space. Conclusions Our more efficient and shortened protocol for inducing the formation of sporophytes will contribute to future studies into the fertilization or the diploid sporophyte generation of P. patens.

In recent years, much attention has been directed towards the integration of dark fermentation process into a biorefinery concept to enhance the energetic gains, thereby improving the competitiveness of this process. The volatile fatty acids (VFAs) from dark fermentative H2-producing processes serve as precursors for the microbial synthesis of a broad spectrum of biotechnologically-important products such as biofuels and biocommodities. These products are desirable substrates for secondary bioprocesses due to their biodegradable nature and affordability. This short review discusses the use of acidogenic-derived VFAs in the production of value-added compounds such as polyhydroxyalkanoates (PHAs) alongside the microbial-based fuels (hydrogen, biogas, and electricity), and other valuable compounds (succinic acid, citric acid, and butanol). The review also highlights the strategies that have been used to enhance the extraction of VFAs from acidogenic effluents and other related waste streams. The application of novel enhancement techniques such as nanoparticles during VFAs recovery is also discussed in this work. Furthermore, the work highlights some of the recent advances in dark fermentation-based biorefinery, particularly the development of pilot-scale processes. Finally, the review provides some suggestions on the advancement of dark fermentation-based biorefineries using VFAs that are derived from acidogenic processes.

In recent years, much attention has been directed towards the integration of dark fermentation process into a biorefinery concept to enhance the energetic gains, thereby improving the competitiveness of this process. The volatile fatty acids (VFAs) from dark fermentative H2-producing processes serve as precursors for the microbial synthesis of a broad spectrum of biotechnologically-important products such as biofuels and biocommodities. These products are desirable substrates for secondary bioprocesses due to their biodegradable nature and affordability. This short review discusses the use of acidogenic-derived VFAs in the production of value-added compounds such as polyhydroxyalkanoates (PHAs) alongside the microbial-based fuels (hydrogen, biogas, and electricity), and other valuable compounds (succinic acid, citric acid, and butanol). The review also highlights the strategies that have been used to enhance the extraction of VFAs from acidogenic effluents and other related waste streams. The application of novel enhancement techniques such as nanoparticles during VFAs recovery is also discussed in this work. Furthermore, the work highlights some of the recent advances in dark fermentation-based biorefinery, particularly the development of pilot-scale processes. Finally, the review provides some suggestions on the advancement of dark fermentation-based biorefineries using VFAs that are derived from acidogenic processes.

Aspergillus flavus is a cosmopolitan saprophytic fungus that infests several foodstuffs and is associated with adverse effects in humans. In Senegal, significant losses of groundnut production are mainly due to contamination caused by this species. This study evaluated in vitro antifungal activities of Cyperus articulatus, Cyperus rotundus and Lippia alba essential oils against A. flavus isolated from peanut seeds. Essential oils obtained by hydrodistillation of rhizomes of the two Cyperus species and leaves of L. alba were analyzed with GC-DIF and GC-MS. The essential oil yields from C. articulatus, C. rotundus and L. alba were 1.1%, 1.3% and 1.7%, respectively. These three samples had the following chemotypes: (i) mustakone (21.4%)/eudesma-4(15)-7-dien-1β-ol (8.8%)/caryophyllene oxide (5.9%), (ii) caryophyllene oxide (25.2%)/humulene epoxyde 2 (35.0%) and (iii) geranial (46.6%)/neral (34.6%). The three oils tested inhibited the growth of A. flavus at concentrations between 100 and 1000 ppm. The L. alba oil was the most effective with total clearance of A. flavus on PDA. For the essential oils of C. rotundus (93.65%) and C. articulatus (78.11%), the highest inhibition rates were obtained with a 1000 ppm dose. Thus, L. alba oil could be used safely as an effective protector of groundnuts against A. flavus.

Rift Valley fever (RVF) is a re-emerging vector-borne zoonosis with a high public health and veterinary impact. In West Africa, many lineages were previously detected, but since 2020, lineage H from South Africa has been the main cause of the outbreaks. In this study, clinical samples collected through national surveillance were screened for RVF virus (RVFV) acute infection by RT-PCR and IgM ELISA tests. Sequencing, genome mapping and in vitro phenotypic characterization in mammal cells were performed on RT-PCR positive samples in comparison with other epidemic lineages (G and C). Four RVFV human cases were detected in Senegal and the sequence analyses revealed that the strains belonged to lineage H. The in vitro kinetics and genome mapping showed different replication efficiency profiles for the tested RVFV lineages and non-conservative mutations, which were more common to lineage G or specific to lineage H. Our findings showed the re-emergence of lineage H in Senegal in 2022, its high viral replication efficiency in vitro and support the findings that genetic diversity affects viral replication. This study gives new insights into the biological properties of lineage H and calls for deeper studies to better assess its potential to cause a future threat in Senegal.

The integration of endomycorrhizal fungi into agricultural practices as inoculum offers the potential to improve plant productivity while reducing reliance on expensive chemical fertilizers, which are not only economically costly but also detrimental to the environment. Mycorrhizal fungi play a crucial role in facilitating plant access to essential mineral elements (such as Phosphorus, Potassium, etc.) and water, particularly in soils characterized by arid and semi-arid conditions. where these resources are often limited. Despite the obvious advantages, the development of arbuscular mycorrhizal fungi (AMF) inoculum production in Africa is progressing on a small scale. This research aims to address this limitation by exploring the feasibility of producing mycorrhizal inoculum on a semi-industrial farm scale, achieved through the control and stabilization of production parameters. Crop residues as peanut shell, rice husk, sugar cane bagasse and millet ears were tested in Leonard jars and pots as alternatives to conventional sand production substrate for the multiplication of mycorrhizal fungi Glomus aggregatum IR27, Funneliformis mosseae, Rhizophagus irregulares and Glomus fasciculatum R10. Significant results were obtained on the peanut shell. Under mass production conditions in farm scale, Glomus aggregatum IR27 showed the best mycorization characteristics with 19.76% intensity and 88.93% frequencies. The study highlighted the critical considerations of irrigation water salt content and substrate sterilization as essential parameters to ensure optimal development of mycorrhizal propagules. Water containing 0.5% salt inhibited the mycorrhization. This negative effect of salt was much more accentuated in unsterilized peanut shell substrate than in sterilized one. This experimental study constitutes a pioneering initiative, potentially replicable in other agricultural areas. Its sustainability is based on the simplicity and efficiency of the technology, which opens the prospect of increasing the number of AMF inoculum production units on a national scale in Senegal.

The study aimed to investigate the chemical composition and antimicrobial and antioxidant activities of the essential oil from dried seeds of Xylopia aethiopica. The essential oil was obtained by hydrodistillation and analyzed by GC/FID and GC/MS. The essential oil yield was 1.35%. Forty-nine compounds were identified in the essential oil with 1,8-cineole (16.3%), β-pinene (14.8%), trans-pinocarveol (9.1%), myrtenol (8.3%), α-pinene (5.9%), and terpinen-4-ol (5.6%) as major components. The antimicrobial activity of this essential oil was studied using disk diffusion and broth microdilution methods on four bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Pseudomonas aeruginosa) and one fungus (Candida albicans). The essential oil exhibited excellent activity against S. aureus, E. faecalis, and C. albicans and moderate activity against E. coli. Among all strains tested, C. albicans showed the best sensitivity with a MIC of 50 mg/mL. The antioxidant activity was examined using a DPPH-free radical scavenging assay. The essential oil of X. aethiopica showed low antioxidant activity (IC50 = 784.604 ± 0.320 mg/mL) compared to that of ascorbic acid and the reference compound (IC50 = 0.163 ± 0.003 mg/mL). The results indicate that consumption of X. aethiopica seeds can reduce the virulence of food-borne pathogens and their resistance to antibiotics.

Introduction : En milieu traditionnel, les feuilles d’Elaeis guineensis sont utilisées pour la prise en charge des plaies. L’objectif de cette étude était de mettre en évidence l'activité cicatrisante des feuilles de cette plante, sur un modèle de brûlure expérimentale de second degré profond, chez le rat de souche Wistar. Matériel et méthodes : Le matériel végétal était constitué d’une poudre de feuilles d’E. guineensis récoltées en Casamance, dans la région Sud du Sénégal. Des rats de souche Wistar provenant de l’animalerie du Laboratoire de Pharmacologie de la Faculté de Médecine, de Pharmacie et d’Odonto-Stomatologie de l’Université Cheikh Anta DIOP de Dakar ont été utilisés pour l’étude pharmacologique. La vaseline officinale pure a servi d’excipient, le benzoate de sodium est ajouté comme conservateur. La Sulfadiazine a été utilisée comme cicatrisant de référence. La poudre de feuilles d’E. guineensis a été extraite avec des solvants de polarité différente (Hexane/Acétate d’éthyle/Méthanol). Une caractérisation de groupes phytochimiques majeurs de la fraction méthanolique a été réalisée sur tube. A partir de la poudre de la fraction méthanolique des feuilles d’E. guineensis, deux pommades à 3 et 10 % dans la vaseline ont été préparées (Qsp 50 g). Le benzoate de sodium a été utilisé à raison de 1,5 g pour 1000 g de pommade. Le benzoate de sodium et la poudre de la fraction méthanolique ont été triturés dans un mortier à l’aide d’un pilon. La vaseline officinale pure a été ajoutée progressivement en triturant légèrement jusqu’à homogénéisation du mélange. L’étude pharmacologique a été menée sur un modèle in-vivo de brûlure expérimentale du second degré profond chez le rat de souche Wistar. Les brûlures expérimentales ont été induites à l'aide d’un cylindre métallique de 3 cm de diamètre et chauffé pendant 3 min. Le cylindre a été appliqué pendant 10 secondes en appuyant un peu sur la surface de la peau rasée des rats, sous anesthésie, afin de provoquer une brûlure de second degré profond. Les pommades ont été appliquées quotidiennement pendant 28 jours. L’activité cicatrisante a été évaluée selon la méthode de KAMOSHIDA avec des scores allant de 1 à 5 selon l’importance de la brûlure et confirmée par des coupes histologiques. Résultats : La caractérisation phytochimique a mis en évidence la présence de composés phénoliques tels que les flavonoïdes et les tanins dans la fraction méthanolique. L’application quotidienne de la vaseline seule ne s’associe pas à une réparation tissulaire. Celle de la pommade à 3 % correspond à un score de 2 à J14 c’est-à-dire, une reconstruction tissulaire des lésions. La cicatrisation est effective au 25ème jour de traitement avec un score de 0,5. La réparation tissulaire est complète au bout de 20 jours d’application et la ré-épithélialisation est complète est observée après 18 jours de traitement. Conclusion : Les feuilles d’E. guineensis sont cicatrisante sur des modèles in-vivo. Ces effets pourraient être dus aux flavonoïdes et tanins présents dans cette fraction.

In this paper, we study numerical approximations of a semilinear parabolic problem in one-dimension, of which the nonlinearity appears both in source term and in Neumann boundary condition. By a semidiscretization using finite difference method, we obtain a system of ordinary differential equations which is an approximation of the original problem. We obtain some conditions under which the positive solution of our system quenches in a finite time and estimate its semidiscrete quenching time. Convergence of the numerical quenching time to the theoretical one is established. Next, we show that the quenching rate of the numerical scheme is different from the continuous one. Finally, we give some numerical results to illustrate our analysis.

This study investigates the effect of zeolite nano-catalyst on the yield of biodiesel and biochar formed from the pyrolysis of tallow (cow fat). Residual waste cow fat was pyrolyzed in a fixed-bed reactor of laboratory-scale volume 2200 cm3, at operating temperatures of 450, 500, 530, and 580 °C and heating rates of 4, 5, and 6 °C/min. The molecular composition of cow fat was analyzed using a gas chromatography molecular spectrograph (GC-MS). It was observed that the biodiesel produced without a catalyst was mainly composed of aromatic carboxylic acids, esters, alkanes, alkenes, and alkanes, while the biodiesel produced with zeolite nano-catalyst consisted mainly of methyl esters, pentanoic acid, heptanoic acid, cyclo-olefins, 4,4-dimethylcyclohexene, butyl-cyclohexane, butyl-cyclopentane, and 1-pentylcyclopentene. A biodiesel yield of 58% was achieved when a 1% zeolite nano-catalyst was used to pyrolyze the tallow at an operating temperature of 530 °C and heating rate of 6 °C/min. When the tallow was pyrolyzed without a zeolitic catalyst, decarboxylation was promoted, and a higher biodiesel yield of 82.78 wt% was achieved. Results from this study revealed that although zeolite nano-catalyst did not show an incremental effect on the yield of biodiesel, it favors biogas production and biochar formation.

In this 21st century, teacher trainers are faced with two systems of ambivalent constraints. They must, on the one hand, obey the injunctions of the educational authorities, by imperatively carrying out digitization in continuing education and, on the other hand, integrate the challenges of digital sobriety into their practices. In this context, we could simply reduce the digital footprint in training in quantitative terms. But for our part, we wanted to explore another path. Indeed, can we not draw inspiration from the paradigm of the “reflective practitioner” and examine whether there is not a means of encouraging a considerable reduction in the number of FADs and reasoning in this way in environmental issues related to digital sobriety. It is a question of questioning the use of reflective practice, and wondering if it cannot be the subject of a device among trainers allowing them to find a compromise in the face of these contradictory injunctions. The methodology applied is qualitative and involves interviews with 3 masters and 1 trainer, the analysis of 3 trainer/trainee interview films and reflective texts. The study shows that if teachers used reflective practice, it would promote digital sobriety.

Objective: Crimean‐Congo haemorrhagic fever (CCHF) is a severe zoonotic arboviral disease that occurs widely in Eastern and Western Europe, Asia and Africa. The disease is becoming of growing public health importance in Senegal. However, analysis of tick infestation, CCHF virus (CCHFV) circulation extent and risk factors during ongoing outbreak are scarce. A thorough outbreak investigation was carried out during a CCHF outbreak in Podor (Northern Senegal) in August 2022. Methods: Ticks and blood samples were collected from animals (cattle, goats and sheep) randomly selected from confirmed CCHF human cases houses, neighbourhoods and surrounding villages. Blood samples were tested for CCHFV antibodies using a commercial enzyme‐linked immunosorbent assay (ELISA) test. Tick samples were screened for CCHFV RNA by RT‐PCR. Results: Overall, tick infestation rate (TIR) and CCHFV seroprevalence of livestock were 52.12% (95% confidence interval (CI): 45.54%–58.64%) and 43.28% (95% CI: 36.33%–50.44%), respectively. The TIRs were 87.7% in cattle, 57.6% in sheep and 20.0% in goats. These rates were significantly associated with location, host species and tick control (p < 0.001) but not with animal age and sex (p > 0.7). CCHFV seroprevalence was 80.4% (95% CI: 67.57%–89.77%) in cattle, 35.4% (95% CI: 25.00%–47.01%) in sheep and 21.2% (95% CI: 12.11%–33.02%) in goats. Age, sex, location, animal host and presence of ticks were significantly associated to the presence of antibodies. The 950 ticks collected included among other species, Hyalomma impeltatum (48.84%) and H. rufipes (10.21%). Five pools of Hyalomma ssp. were found CCHFV RT‐PCR positive. These infected ticks included 0.86% (4/464) of H. impeltatum collected on cattle and sheep and 1.03% (1/97) of H. rufipes collected on a sheep. Conclusions: To our knowledge, this is the first report on the extend of tick infestation and CCHFV infection in livestock during an outbreak in Senegal. The results highlight the risk of human infections and the importance of strengthening vector, animal and human surveillance as well as tick control measures in this area to prevent CCHF infections in humans. [ABSTRACT FROM AUTHOR]

Summary: The sexual reproductive organs of bryophytes – in which gametes necessary for fertilization are produced, namely, male antheridia and female archegonia – are formed from vegetative haploid gametophytes. In dioicous bryophytes such as Marchantia polymorpha, the genes within the sex‐determining regions in distinct sexual strains have been identified. However, in monoicous bryophytes such as Physcomitrium patens, how the two sex fates are specified on the same gametophyte remained unknown.Here, we identified an RWP‐RK domain‐containing transcription factor in P. patens, PpRKD, as a factor required for the development of female organs, based on the absence of archegonia in loss‐of‐function Pprkd mutants and the specific expression of PpRKD in archegonia.When ectopically induced, the expression of PpRKD resulted in the repression of antheridial development and the emergence of archegonium‐like organs. Furthermore, the young primordia inside the antheridial bundle displayed typical archegonial division patterns, suggesting that PpRKD confer female fate to antheridium primordia.This study represents the first instance where the function of sex determination has been identified among RKD orthologs in land plants. This finding should provide a new framework for the molecular evolutionary context of the genes in the RKD family, considering the recent elucidation of their roles in algae. [ABSTRACT FROM AUTHOR]

Crimean–Congo hemorrhagic fever (CCHF), the most widespread tick-borne viral human infection, poses a threat to global health. In this study, clinical samples collected through national surveillance systems were screened for acute CCHF virus (CCHFV) infection using RT-PCR and for exposure using ELISA. For any CCHF-positive sample, livestock and tick samples were also collected in the neighborhood of the confirmed case and tested using ELISA and RT-PCR, respectively. Genome sequencing and phylogenetic analyses were also performed on samples with positive RT-PCR results. In Eastern Senegal, two human cases and one Hyalomma tick positive for CCHF were identified and a seroprevalence in livestock ranging from 9.33% to 45.26% was detected. Phylogenetic analyses revealed that the human strain belonged to genotype I based on the available L segment. However, the tick strain showed a reassortant profile, with the L and M segments belonging to genotype I and the S segment belonging to genotype III. Our data also showed that our strains clustered with strains isolated in different countries, including Mauritania. Therefore, our findings confirmed the high genetic variability inside the CCHF genotypes and their introduction to Senegal from other countries. They also indicate an increasing CCHF threat in Senegal and emphasize the need to reinforce surveillance using a one-health approach.

IntroductionWest African men who have sex with men (MSM) remain at substantial risk of contracting HIV. Pre-exposure prophylaxis (PrEP) can be an effective game-changer in reducing the number of HIV infections in MSM communities. To optimize the roll-out of PrEP, we need to better understand how we can increase its uptake. The objective of this study was to explore the perceptions of West African MSM toward PrEP and their proposed strategies to overcome barriers to PrEP uptake within their communities.MethodsBetween April 2019 and November 2021, we conducted 12 focus group discussions with 97 MSM not taking PrEP, and 64 semi-structured interviews with MSM taking PrEP, in Burkina Faso, Côte d'Ivoire, Mali, and Togo. Data collection and analysis were guided and conducted by local research teams, enabling a community-based participatory approach. A coordinating researcher collaborated with these local teams to analyze the data guided by a grounded theory approach.ResultsThe results show that participants were generally positive toward PrEP and that MSM communities have become more aware of PrEP for the study. We identified three main strategies for increasing PrEP uptake. First, participants proposed to raise awareness and improve knowledge of HIV as they considered the self-perceived risk of MSM in their communities to be low. Second, because of existing misconceptions and false information, participants proposed to improve the dissemination of PrEP to allow for informed choices, e.g., via peers or PrEP users themselves. Third, as oral PrEP also entails a risk of being associated with HIV or homosexuality, strategies to avoid stigmatization (e.g., hiding pills) were deemed important.DiscussionThese findings indicate that the roll-out of oral PrEP and other future PrEP modalities should be accompanied by raising awareness and improving knowledge on HIV, and wide dissemination of information that focuses on the health-promoting aspect of these tools. Tailored delivery and long-acting PrEP modalities will be important to avoid potential stigmatization. Sustained efforts to prevent discrimination and stigmatization based on HIV status or sexual orientation continue to be highly important strategies to address the HIV epidemic in West Africa.

Résumé : Cet article a pour objectif d’étudier les types d’interactions utilisées dans l’apprentissage du français, langue seconde au Sénégal avec l’objectif d’examiner le degré d’implication de l’apprenant en se fondant sur une perspective interactionniste du discours. Il s’agit de mettre l’accent sur le rôle des relations élève/maître dans la leçon, sur l’activité cognitive de l’apprenant et sur la prééminence de la communication dans l’apprentissage. Dans cette dynamique, les dimensions relatives au temps de parole de l’apprenant, à son activité dans la leçon, à la motivation et à la collaboration élève/élève seront respectivement analysées. Sur le plan méthodologique, notre étude s’appuie sur un corpus tiré de 5 leçons de langage en Cours d’Initiation (CI) d’une durée globale de 300 minutes à partir des trois écoles d’application du Centre Régional de Formation des Personnels de l’Éducation (CRFPE) de Dakar. L’utilisation du Logiciel Atlas nous a permis de procéder à une analyse des données qualitatives et quantitatives issues des transcriptions des corpus enregistrés au moyen d’une série de techniques itératives de codage, de catégorisation et de cadrage. L’analyse met principalement l’accent sur le repérage des types d’interactions et le niveau d’implication des élèves dans les leçons de langage. Il ressort de cette étude que les enseignants monopolisent beaucoup la parole dans les leçons de langage au point de surpasser le temps d’intervention des élèves ; ils proposent très peu de situations de communication pouvant favoriser l’activité réelle des apprenants ; enfin, les activités langagières orales que les enseignants organisent en groupe ou en binôme ne développent point l’expression des élèves. Mots-clés : Analyse interactionnelle, français langue seconde, langage, école primaire, approche communicative