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Introduction: The Velingara depression, located in the southern part of Senegal, consists in a near-circular basin of about 40 km of diameter, bordered by a subtle rim up to only 60 m above the altitude of the basin. The central part of the depression is occupied by rice fields, marshes and a lake. Eocene and post-Eocene deposits of sediments fill the depression, while lateritic cuirass is exposed at the rim. There are almost no outcrops of basement rocks be - low the recent sediments, except in an irrigation channel where quartz veins and mica schists have been reported [1]. Using satellite imagery and a compilation of other various old data (collected samples, shallow drillings, local resis - tivity surveys, regional gravity data), previous studies [1, 2] have postulated that Velingara corresponds to a buried complex impact crater with a central uplift. The used data are difficult to interpret and sometimes not available. Some PDFs seem to have been observed on samples, but again, reports are hard to confirm. The Bouguer gravity data stored by the Bureau Gravimétrique International (BGI) do not really show a significant anomaly unveiling a circular structure, and indicate a WNW-ESE regional gradient linked to the presence of the thick sedimentary Casamance basin to the west, and to the crystalline basement rocks of Guinea-Bissau to the south. No airborne magnetic data were acquired in the area (only outside, in Casamance and SE of Senegal). We did not have access to cited electrical resistivity local cross-sections [2], reporting shallow resistive blocks which may indicate uplifted basement rocks. Methology: In the framework of an international program between France and Senegal, a new geophysical survey has been performed in March 2022, with the aim to identify the best place for a possible drilling in the future. Ground gravity and magnetic field measurements were acquired at about 2 km spacing (sometimes 500 m in the central part, sometimes more than 2 km outside) within the depression and crossing the ring. A Scintrex CG-5 gravimeter was used for gravity measurements, accompanied by an Emlid Reachview RS-2 GPS mobile antenna. Another RS-2 GPS antenna was used as GPS reference base station during each day of prospection. Post-Processing Kinematic (PPK) treatment was then applied to these GPS data to get circa 4 cm resolution on the vertical positioning of each gravity measurements. All classical corrections were then performed to the raw gravity measurements to calculate the complete Bouguer gravity anomaly using 2400 kg m-3 as density of regional rocks. Magnetic field measurements have been acquired using a MMPOS Overhauser magnetometer. The anomaly was computed after substraction of the ambient regional field measured in parallel by a Geometrics G856 base station. The Total Magnetic Intensity anomaly was then reduced to the pole. Preliminary results: The Bouguer gravity residual signal clearly shows a circa 15 mGal negative circular anomaly centered nearby the lake, with a diameter of about 10 km. Outside this negative signal, we do not see any other circular signals. It means that the topographical ring is much larger than the gravity anomaly. The magnetic field anomaly map reveals significant anomalies of about 50 nT, which may argue in favor of the presence of shallow buried crystalline rocks. Discussion: these results confirm the presence of a low density formation in the center of the Velingara depres - sion. They could be brecciated / fractured formations of crystalline (magnetic) basement, or post impact sediments. Modeling of the anomalies will be performed, in parallel to the drilling in the central part of the depression. Col - lected samples will be also searched for shock indicators. [ABSTRACT FROM AUTHOR]

Background: An increase in pandemics of zoonotic origin has led to a growing interest in using statistical prediction to identify hotspots of zoonotic emergence. However, the rare nature of pathogen emergence requires modellers to impose simplifying assumptions, which limit the model's validity. We present a novel approach to hotspot mapping that aims to improve validity by combining model-based insights with expert knowledge., Methods: We conducted a systematic literature review to identify predictors for zoonotic emergence events in three priority virus families (Filoviridae, Coronaviridae, and Paramyxoviridae). We searched PubMed, Web of Science, Agricola, medRxiv, bioRxiv, Embase, CAB Global Health, and Google Scholar on Oct 14-28, 2021, with no restrictions on language or the date of publication. Articles suggested by subject matter experts and those identified by a review of reference lists were also included. We used regularised regression to fit a model to the data extracted from the literature and produced maps of ranked risk. In a series of workshops in five countries (Kenya, Peru, Senegal, Thailand, and Viet Nam), experts in zoonotic diseases produced qualitative hotspot maps based on their expertise, which were compared with the model-derived maps., Findings: 425 articles were analysed, from which 19 predictors and 1068 outcome events were identified. The in-sample misclassification error was 0·365, and 89% of participant-selected zones were ranked as moderate or high risk by the model. Participant-selected zones were too large to be actionable without further refinement. Discordance was probably due to missing predictors for which no valid data exist, and homogeneity imposed by our global model., Interpretation: Concordance between the two sets of maps supports the validity of each. Because model-based and participatory strategies have non-overlapping limitations, the results can be harmonised to minimise bias, and model-based results could be used to refine participant-selected zones. This approach shows potential for refining deployment of countermeasures to prevent future pandemics., Funding: US Agency for International Development., Competing Interests: Declaration of interests We declare no competing interests., (Copyright © 2025 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC 4.0 license.)

The West African Monsoon (WAM) system is the main source of rainfall in the agriculturally based region of the Sahel. Understanding transport across the WAM is of crucial importance due to the strong impact of humidity and dust pathways on local cloud formation. However, the description of this transport is challenging due to its 3D complex nature. Lagrangian Coherent Structures (LCS) simplify transport description across the WAM by providing a geometrical partition of the troposphere into domains. Air parcels within each domain have similar dynamical characteristics. LCS make it possible to achieve an integrated vision of transport pathways across this system. Using this approach we unveil new connections in the WAM system. In particular, we identify transport pathways between the Tropical Easterly Jet (TEJ) and the African Easterly Jet (AEJ). Furthermore, the clockwise circulation associated with the divergent upper part of the Sahara heat low is clearly delimitated. Additionally, we show the presence of mixing regions in the AEJ and the lower part of the TEJ that are linked to pathways to sources of dust and humidity.

After presentations of the principles of limb salvage and soft-tissue coverage for Gustilo III open tibia fractures, this third part is dedicated to management of tibial non-unions in low-resource settings. Inter-tibiofibular grafting and the induced membrane technique are preferred because they make it possible to deal with almost all situations. Key technical points of these methods are presented, followed by treatment guidelines based on Catagni's classification and bone defect size.

After limb salvage based on debridement and external fixation, Gustilo IIIB open tibia fractures must undergo soft-tissue repair within 7 days. In low-resource setting, the coverage is performed with pedicled flaps only, which can be used by any orthopedic surgeon after minimal training. The authors describe here the simplified use of 7 basic flap transfers that can deal with almost all soft tissue defects. The diffusion of these techniques in developing countries is crucial for limiting functional and trophic effects related to prolonged exposure of the fracture site.

In developing countries, road traffic accidents result in many cases of open trauma, especially fractures, with the tibia area at particular risk in motorcycle crashes. Despite a high prevalence of severe leg trauma with multi-tissue injuries, few studies have focused on the challenge of their reconstruction in these limited-resource settings. The first part of this review presents the surgical strategy. Limitations and principles of initial limb salvage are detailed. Orthopedic procedures for early damage control, based on debridement and temporary bone stabilization, are often required. The priority is to shorten the time to initial surgical management to avoid infection, which jeopardizes reconstruction.

Although the development of multitissue limb reconstruction has reduced the role of post-traumatic primary amputation of the leg, some patients should nonetheless undergo emergency amputations. In developing countries, the socioeconomic context associated with the limited health care supply compromises still further the prognosis of preservation efforts. The decision criteria for surgery are thus different in these settings. The choice of emergency leg amputation or attempted preservation in developing countries depends on the epidemiology of severe leg trauma, the local and general prognosis, and the practice conditions. Three factors must be combined before limb preservation can be attempted: adequate local and general adequate wound elements, an available, experienced surgeon with a competent care structure, and a favorable social context.

Oral diseases, mainly tooth decay and periodontal disease, are among the most common conditions in the world. The tooth decay is very prevalent in developing countries and particularly in disadvantaged backgrounds where insecurity and its corollaries prevail. Thus, our study focused on one of these places: the prisons, characterized by deprivation of liberty, monotony, boredom, and the difficult conditions of detention, brief by a total dependence of the detainee. The aim of this study was to determine the DMFT (Decayed, Missing, Filled Teeth) in detainees dwelling in prisons in Dakar. This cross sectional study included 754 detainees aged 18 years and more with a stay exceeding more than a year, in one of the four main prisons of the capital city, Dakar. The majority of detainees was males (90%), aged between 18 and 35 years (63%) and was staying at "Camp penal" (65%). The proportion of inmates with at least one tooth cavity was 81.3%, those with teeth sealed was 26.1% and the prisoners with missing teeth reached 70.6%. The highest average DMFT was noted at "Camp penal" (7.3) among men (6.5) and among inmates aged 36 to 45 years (6.1) with a significant difference. The tooth decay is particularly worrying in the prison population, hence the urgency to establish a programme of prevention and care of oral diseases in this environment.

Molecular resistance mechanisms affecting the efficiency of receptor tyrosine kinase inhibitors such as gefitinib in non-small-cell lung cancer (NSCLC) cells are not fully understood. Amphiregulin (Areg) overexpression has been proposed to predict NSCLC resistance to gefitinib and we have established that Areg-overexpressing H358 NSCLC cells resist apoptosis. Here, we demonstrate that Areg prevents gefitinib-induced apoptosis in NSCLC cells. We show that H358 cells are resistant to gefitinib in contrast to H322 cells, which do not overexpress Areg. Inhibition of Areg expression by small-interfering RNAs (siRNAs) restores gefitinib sensitivity in H358 cells, whereas addition of recombinant Areg confers resistance in H322 cells. Areg knockdown overcomes resistance to gefitinib and induced apoptosis in NSCLC H358 cells in vitro and in vivo. Under gefitinib treatment, Areg decreases the expression of the proapoptotic protein BAX, inhibits its conformational change and its mitochondrial translocation. Thus, in the presence of Areg, gefitinib-mediated apoptosis is reduced because BAX is sequestered in the cytoplasm. This suggests that treatments using epidermal growth factor receptor (EGFR) inhibitors may be poorly efficient in patients with elevated levels of Areg. These findings indicate the need for inhibition of Areg to enhance the efficiency of the EGFR inhibitors in patients suffering NSCLC.

Multiple molecular resistance mechanisms reduce the efficiency of receptor tyrosine kinase inhibitors such as gefitinib in non-small cell lung cancer (NSCLC). We previously demonstrated that amphiregulin (Areg) inhibits gefitinib-induced apoptosis in NSCLC cells by inactivating the proapoptotic protein BAX. In this part of the investigation, we studied the molecular mechanisms leading to BAX inactivation. We show that Areg prevents gefitinib-mediated acetylation of Ku70. This augments the BAX-Ku70 interaction and therefore prevents BAX-mediated apoptosis. Accordingly, Areg or Ku70 knock down restore BAX activation and apoptosis in gefitinib-treated H358 cells in vitro. In addition, overexpression of the histone acetyltransferase (HAT) CREB-binding protein (CBP) or treatments with histone deacetylase (HDAC) inhibitors sensitize H358 cells to gefitinib. Moreover, a treatment with vorinostat, a HDAC inhibitor strongly sensitized tumors to gefitinib in vivo. These findings suggest new prospects in combining both HDAC and epidermal growth factor receptor inhibitors for the treatment of NSCLC.

The purpose of this study is to describe the outcome of total hip arthroplasty for management of aseptic osteonecrosis of the femoral head due to sickle cell disease. This consecutive series carried out over a 7-year period in 38 patients with a sickle-cell anaemia includes a total of 48 cemented prosthesis. The mean follow-up period was 5 years. Arthroplasty restored normal hip function (PMA score = 18) in 64% of cases. In 32% of cases the PMA score was more than 15. Pain was greatly reduced with total relief being achieved in 94% of cases. Walking ability also improved with 85% of patients having an unlimited walking distance. Radiological examination demonstrated edging on 36% of cupulas and 29% of the shafts. Complications were observed in 19% of cases. The main complications were loosening and dislocation of the prosthesis. Although the complication rate was high, functional outcomes in this series were good. These findings indicate that arthroplasty should be considered as the treatment of choice for aseptic osteonecrosis due to stage 3 and 4 sickle-cell disease in young patients. Use of uncemented implant and type of frictional torque are discussed.

To examine young people's reactions to and understanding of HIV prevention messages developed for MTV's global HIV prevention campaign Staying Alive, videotaped campaign materials were shown to focus group discussion (FGD) participants living in urban areas of Brazil, Kenya, Nepal, and Senegal. Responses related to "personal involvement" with the message were identified in the data from these FGDs and were examined in relationship to the emerging message themes, the message format (public service announcements [PSAs] vs. documentary), cultural context (site), and participant gender. Across groups, greater personal involvement (measured by personal connections, emotional reactions, and lessons learned) was found in responses about the documentary format compared to the PSA format. Exceptions were found for specific PSAs that were considered more relevant within specific gender or cultural contexts. Implications of findings for global campaigns were considered.

Objectives: To document the level of HIV infection in Senegal and also to review evidence of the impact of efforts in prevention, developed by the National AIDS Control Programme and the Civil Society, on the level of the HIV epidemic., Methods: Research, compilation and critical review of all relevant data on HIV and sexually transmission diseases (STDs) epidemiology, sexual behaviour, and the efforts in prevention developed in Senegal., Results: From 1989 to 1996, the levels of HIV infection estimated in four sentinel urban regions remained stable at around 1.2% in the population of pregnant women, and at 3% in male STD patients. It had increased to 19% in female sex workers. A strong political and community commitment led to an early response to the HIV/AIDS epidemic that has been extended since 1986. Blood transfusion safety was established at the start of the HIV epidemic. The level of knowledge of preventive practices relating to HIV/AIDS among the general population exceeded 90% in the early 1990s. From 1991 to 1996, a 30% to 66% decrease of the STD prevalence rates was observed in pregnant women and sex workers in Dakar. In 1997, 33% of men aged 15-49 years in Dakar reported having had sex with non-regular partners. Among them 67% reported condom use., Conclusions: It is not possible to know what the course of the HIV epidemic in Senegal would have taken in the absence of efforts at prevention. Certainly, several factors that pre-dated the occurrence of AIDS in Senegal laid the groundwork for a positive response. However, data from a number of sources do reveal the successfulness of efforts in prevention. From available data, Senegal can rightfully claim to have contained the spread of HIV by intervening early and comprehensively to increase knowledge and awareness of HIV/AIDS and to promote safe sexual behaviour.

Objective: To report the findings of qualitative studies designed for use in improving sexually transmitted disease (STD) programs. The studies explore illness conceptions and treatment behaviors for STD in five African countries. These targeted intervention research (TIR) studies were performed on clinic-based and community-based samples in representative communities and utilized a variety of qualitative research methods (e.g. in-depth and key informant interviews, focus group discussions)., Findings: Study findings revealed that community members' explanations of symptoms, classification of illnesses, and perceptions of whether symptoms are pathological or serious influence individual health-care-seeking behaviors. Data also showed that local terms for STD are often disparaging and do not fit into biomedical designations. STD patient care-seeking frequently reflects an ordered, albeit loosely constructed, process of elimination in pursuit of symptom relief, wherein alternative treatments are tried and proven effective or abandoned., Conclusions: The TIR studies highlight the importance of community-specific strategies aimed at increasing prompt care seeking at qualified biomedical facilities. Information from study data should lead programs to sensitize health professionals to community understanding about STD and to design services and communication programs that are meaningful and appropriate to local contexts.