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The accumulation of dust on the surface of solar panels reduces the amount of sunlight reaching the solar cells and results in a decrease in panel performance. To avoid this loss of production and thus, to improve the performance capacity, solar panels must be cleaned frequently. The West African region is well known for its high solar energy potential. However, this potential can be reduced by the high occurrence of dust storms during the year. This article aims to provide a contribution to the construction of a meteorological information service for solar panel cleaning operations at Diass solar plant in Senegal (Western Sahel). It is based on a full year in situ experiment comparing the power loss due to dust between solar panels cleaned at different frequencies and those not cleaned. The model to determine the cleaning frequencies is based on the deposition rate of airborne particles, the concentration of airborne particles, and the density of the dust that has a major impact on the power loss. Cleaning frequencies are presented at seasonal scale because in the study area, dust episodes differ according to the seasons. A cost–benefit analysis is also performed to demonstrate the advantage of using weather information service to support the dust cleaning operations at Diass plant. As results, it is found that cleaning every 3 weeks is required during the dry seasons, December–January–February and March–April–May. During the rainy season, cleaning every 5 weeks is recommended in June–July–August, while in September–October–November cleaning every 4 weeks is sufficient to maintain an optimal performance of the solar panel. The total costs of cleaning operations based on these results are reduced compared to the current costs of cleaning and the benefits are much higher than without cleaning action.

This study sought to examine the kinds of mindsets that the participating teachers demonstrated in their teaching and the impact of teachers' mindsets on their ways of teaching mathematics and science. Seven teachers who were teaching science or mathematics in high-needs schools in the urban context of the Bronx, New York were the participants of the study, with interview data and analysis provided for three participants representing the low, medium, and high mindset groupings. Qualitative research method was used to analyze the data. The data were collected through three different questionnaires, lesson observations, and interviews. Data analysis revealed that six participating teachers demonstrated a growth mindset with different degrees and one teacher seemed to have a fixed mindset. Teachers with a growth mindset adopted instructional practices that are more aligned with those that are recommended in the growth mindset literature.

Abstract Introduction Abdominal surgical emergencies have a high mortality rate. Effective management primarily relies on the early identification of patients at high risk of postoperative complications. The objective of our study was to determine the prognostic factors associated with poor outcomes from abdominal surgical emergencies in Senegal and to establish a predictive score for mortality for preoperative risk evaluation (NDAR (New Death Assessment Risk) score). Methodology This was a retrospective national cross-sectional study conducted over one year in 14 regions of Senegal. Adult patients (aged > 15 years) who presented with a traumatic or non-traumatic abdominal surgical emergency were included. The studied variables included clinical and paraclinical data. The variable of interest was death within 30 days of the surgery. Logistic regression was used to identify the factors independently associated with mortality. Risk factors identified after logistic regression analysis were weighted using odds ratio (OR) values rounded to the nearest whole number. The predictive capacity of the score was evaluated by analyzing the ROC (Receiver Operating Characteristic) curve based on the area under the curve (AUC). Results A total of 1114 patient records were included, with a mortality rate of 4.4%. Diagnoses were observed in patients included appendicitis in 39.8% of cases (n = 444), followed by peritonitis in 22.3% (n = 249), intestinal obstruction in 18.5% (n = 205), strangulated hernias in 10.5% (n = 117), and abdominal trauma in 6.1%. Logistic regression, established the following scores: age > 40 years (score 2), ASA status grade 2 or higher (score 1), presence of a positive QSIRS score (score 2), diagnosis of peritonitis (score 2), diagnosis of intestinal obstruction (score 1), and the presence of intestinal necrosis (score 3). The score is positive if the total is strictly greater than 5, indicating a 17.7% risk of mortality. This score had a high predictive capacity with an AUC of 0.7397. Conclusion This study enabled the establishment of a score that allows for the early identification of at-risk patients, even in constrained resource settings, facilitating appropriate perioperative management and timely surgical intervention to reduce the risk of complications. This approach, focused on early recognition of high-risk patients, is crucial for improving clinical outcomes in abdominal surgical emergencies.

Fatou Aw,1 Mouhamadou Bamba Ndiaye,1 Simon Antoine Sarr,1 Malick Bodian,1 Aliou Alassane Ngaide,2 Alassane Mbaye,2,3 Adama Kane,1 Abdoul Kane,4 Maboury Diao,1 Serigne Abdou Ba1 1Department of Cardiology, Aristide Le Dantec Teaching Hospital, 2Department of Cardiology, General Hospital of Grand Yoff, 3Department of Cardiology, Teaching Hospital of Fann, 4Cheikh Anta Diop University of Dakar, Dakar, Senegal Background: The study of the right ventricle (RV) is of particular interest as it is believed to be involved in several heart diseases. Peripartum cardiomyopathy (PPCM) is characterized by left ventricular systolic dysfunction occurring between the last month of pregnancy and the fifth month postpartum. It is often combined with RV dysfunction, but this has rarely been described in the literature. The main aim of this study was to assess the prevalence of RV dysfunction in a PPCM population.Methods: We conducted a prospective and investigative study at the Cardiac Clinic of the Aristide Le Dantec Teaching Hospital in Dakar, Senegal, between March and June 2013. All patients hospitalized during the study period and meeting the diagnostic criteria for PPCM were included.Results: During the study period, 326 patients were hospitalized in the cardiology department; 19 were diagnosed with PPCM corresponding to a hospital prevalence of 5.8%. All patients had left ventricular dysfunction, with an average ejection fraction of 23.01%±9.73% at the Simpson biplane. Based on the tricuspid annular plane systolic excursion (TAPSE), 11 out of the 19 patients (57.9%) had RV systolic dysfunction. Ten patients (52.6%) had an Sa tricuspid wave (speed of the systolic wave to the tricuspid ring in tissue Doppler) below the standard. The average RV area shortening was 23.73%±14.16%, with extremes of 7.8% and 53.7%. Fifteen patients (78.9%) had a rate of shortening fraction of the surface area of RV below the standard. When the other parameters were taken into account, 15 patients (78.9%) had at least 3 of the following indexes altered: fractional area change (FAC), Sa tricuspid, TAPSE, and the ratio between the sum of both isovolumic times and the ejection time (TEI index).Conclusion: RV dysfunction is common in PPCM. In view of the prognostic interest on the right ventricle; its evaluation must take into account all of the measurement parameters in order to allow for better detection. Keywords: peripartum cardiomyopathy, right ventricular dysfunction, heart failure, Dakar, Sénégal

Introduction: The management of gastroschisis remains problematic in low- and middle-income countries with high perioperative mortality. The objective of this work was to make an initial assessment of our management of gastroschisis. Materials and Methods: This was a monocentric and cross-sectional study including all newborns with gastroschisis between January 2017 and December 2021 in the Pediatric Surgery and Anesthesia Resuscitation Department of the Aristide Le Dantec University Hospital Center from Dakar. The socio-demographic, diagnostic, therapeutic and evolutionary parameters were studied. Results: Eighteen cases of gastroschisis (11 males and 7 females). The mothers’ mean age were 23.1 ± 5.7 years old. Only one antenatal diagnosis was made. The mean gestation age were 36.5 ± 1.5 weeks. On admission, the mean age was 16.8 ± 6.3 h and the mean weight 2244 ± 260.3 g. Gastroschisis was complex in four patients. Primary bowel reintegration was performed in 8 cases (44.4%) and progressive reintegration using an Applied Alexis retractor in 9 newborns (55.6%). Main complications were respiratory distress (28.3%) and sepsis (22.2%). The mean duration of return of oral feeding was 5.1 ± 1.9 days. Mortality was 94.4% (17/18). Conclusion: Reducing gastroschisis-related mortality in our low-income countries remains a major challenge.

Aerial vehicles are increasingly relying on connectivity to cellular networks, with 5G new radio (NR) and 6G technologies deemed critical for the next generation of indoor and outdoor positioning systems. Conventional time of arrival approaches require time synchronisation between base stations and vehicles, and a clock bias greater than 30 ns can result in a positioning inaccuracy above 10 m. This work, thereby, proposes an integrated positioning technique based on RF fingerprinting using ray-tracing data and reinforced with machine learning. The system leverages advanced sensing technologies, NR communications, and AI-driven random forests to enhance the precision and reliability of air vehicle positioning, contributing to safer and more efficient air travel and autonomous flight operations. The developed solution is evaluated in a representative urban canyon environment, in which the performance of conventional radio-based positioning systems is often degraded. Notably, a supervised learning algorithm based on the received signal strength and time of arrival is shown to exhibit an accuracy of under 3 m in 75% of the areas studied.

Oocyte activation is a fundamental event in mammalian fertilization and is initiated by a cascade of calcium signaling and oscillation pathways. Phospholipase C zeta (PLCζ) is involved in modulating cortical granule exocytosis, releasing oocyte meiotic arrest, regulating gene expression, and early embryogenesis. These processes are considered to be initiated and controlled by PLCζ activity via the inositol-1,4,5-triphosphate pathway. The decrease or absence of functional PLCζ due to mutational defects in protein expression or maintenance can impair male fertility. In this literature review, we highlight the significance of PLCζ as a sperm factor involved in oocyte activation, its mechanism of action, the signaling pathway involved, and its close association with oocyte activation. Finally, we discuss the relationship between male infertility and PLCζ deficiency.

Abstract Background This study aimed to demonstrate that the genomic material of SARS-CoV-2 can be isolated from strips of COVID-19 rapid diagnostic test cassettes. Method It was a prospective cross-sectional study involving patients admitted to treatment centers and sampling sites in the city of Conakry, Guinea. A total of 121 patients were double sampled, and 9 more patients were tested only for RDT. PCR was conducted according to the protocol of the RunMei kit. Sequencing was performed by using the illumina COVIDSeq protocol. Nine COVID-19 RDTs without nasopharyngeal swabs were in addition tested. Result Among the 130 COVID-19 RDTs, forty-seven were macroscopically positive, whereas seventy-two were positive according to PCR using RDT strip, while among the 121 VTM swabs, sixty-four were positive. Among eighty-three negative COVID-19 RDTs, twenty-seven were positive by PCR using RDT strip with a geometric mean Ct value of 32.49 cycles. Compared to those of PCR using VTM, the sensitivity and specificity of PCR using RDT strip were estimated to be 100% and 85.96%, respectively, with 93.39% test accuracy. Among the fifteen COVID-19 RDT extracts eligible for sequencing, eleven had sequences identical to those obtained via the standard method, with coverage between 75 and 99.6%. Conclusion These results show that COVID-19 RDTs can be used as biological material for the genomic surveillance of SARS-CoV-2.

Abstract Background Drug resistance in Plasmodium falciparum is a major threat to malaria control efforts. Pathogen genomic surveillance could be invaluable for monitoring current and emerging parasite drug resistance. Methods Data from two decades (2000–2020) of continuous molecular surveillance of P. falciparum parasites from Senegal were retrospectively examined to assess historical changes in malaria drug resistance mutations. Several known drug resistance markers and their surrounding haplotypes were profiled using a combination of single nucleotide polymorphism (SNP) molecular surveillance and whole genome sequence based population genomics. Results This dataset was used to track temporal changes in drug resistance markers whose timing correspond to historically significant events such as the withdrawal of chloroquine (CQ) and the introduction of sulfadoxine-pyrimethamine (SP) in 2003. Changes in the mutation frequency at Pfcrt K76T and Pfdhps A437G coinciding with the 2014 introduction of seasonal malaria chemoprevention (SMC) in Senegal were observed. In 2014, the frequency of Pfcrt K76T increased while the frequency of Pfdhps A437G declined. Haplotype-based analyses of Pfcrt K76T showed that this rapid increase was due to a recent selective sweep that started after 2014. Discussion (Conclusion) The rapid increase in Pfcrt K76T is troubling and could be a sign of emerging amodiaquine (AQ) resistance in Senegal. Emerging AQ resistance may threaten the future clinical efficacy of artesunate-amodiaquine (ASAQ) and AQ-dependent SMC chemoprevention. These results highlight the potential of molecular surveillance for detecting rapid changes in parasite populations and stress the need to monitor the effectiveness of AQ as a partner drug for artemisinin-based combination therapy (ACT) and for chemoprevention.

Abstract Natural spices play an essential role in human nutrition and well-being. However, their processing on different scales can expose them to potential sources of contamination. This study aimed to describe the bacterial community genomic footprint in spices sold in Senegal. Spice samples were collected in August 2022 in Saint-Louis, Senegal. The genomic region coding bacterial 16S rRNA was then amplified and sequenced using Oxford Nanopore Technology (ONT). Sequencing was carried out on two batches of samples, one containing part of the “Local Spices or Herbs” (n = 10), and the other, a mixture of 7 spices, Curcuma, Thyme and the other part of the “Local Spices or Herbs” (n = 39). Results showed high bacterial diversity and the predominance of Escherichia coli and Salmonella enterica in samples, with total reads of 65,744 and 165,325 for the two batches, respectively. The sample category “Homemade mixture of food condiments “, which includes all “Local Spices or Herbs” samples, showed remarkable bacterial diversity. These were followed by Curcuma, a blend of 7 spices and thyme. Also, the different categories of spices studied show similarities in their bacterial composition. These results highlight the microbial community’s highly diverse genomic profile, including pathogenic bacteria, in spice samples.

Abstract Climate change is recognised to lead to spatial shifts in the distribution of small pelagic fish, likely by altering their environmental optima. Fish supply along the Northwest African coast is significant at both socio-economic and cultural levels. Evaluating the impacts of climatic change on small pelagic fish is a challenge and of serious concern in the context of shared stock management. Evaluating the impact of climate change on the distribution of small pelagic fish, a trend analysis was conducted using data from 2363 trawl samplings and 170,000 km of acoustics sea surveys. Strong warming is reported across the Southern Canary Current Large Marine Ecosystem (CCLME), extending from Morocco to Senegal. Over 34 years, several trends emerged, with the southern CCLME experiencing increases in both wind speed and upwelling intensity, particularly where the coastal upwelling was already the strongest. Despite upwelling-induced cooling mechanisms, sea surface temperature (SST) increased in most areas, indicating the complex interplay of climatic-related stressors in shaping the marine ecosystem. Concomitant northward shifts in the distribution of small pelagic species were attributed to long-term warming trends in SST and a decrease in marine productivity in the south. The abundance of Sardinella aurita, the most abundant species along the coast, has increased in the subtropics and fallen in the intertropical region. Spatial shifts in biomass were observed for other exploited small pelagic species, similar to those recorded for surface isotherms. An intensification in upwelling intensity within the northern and central regions of the system is documented without a change in marine primary productivity. In contrast, upwelling intensity is stable in the southern region, while there is a decline in primary productivity. These environmental differences affected several small pelagic species across national boundaries. This adds a new threat to these recently overexploited fish stocks, making sustainable management more difficult. Such changes must motivate common regional policy considerations for food security and sovereignty in all West African countries sharing the same stocks.

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.

Malick Bodian,1 Fatou Aw,1 Mouhamadou Bamba Ndiaye,1 Adama Kane,1 Modou Jobe,1 Alioune Tabane,1 Alassane Mbaye,2 Simon Antoine Sarr,1 Maboury Diao,1 Moustapha Sarr,1 Serigne Abdou Bâ1 1Department of Cardiology, Aristide Le Dantec Teaching Hospital, 2Grand Yoff General Hospital, Dakar, Senegal Abstract: Routine implantation of pacemakers and implantable cardioverter defibrillators is not commonly associated with complications. However, in some cases we see misplacement of pacemaker leads which is most often related to the presence of underlying cardiac anomalies. We report the case of misplacement of a pacemaker lead into the left ventricle of a 56-year-old patient paced in VVI/R mode and with a tined type pacemaker lead because of a symptomatic complete atrioventricular block. Electrocardiogram showed a pacemaker-generated rhythm with a right bundle branch block pattern. Chest X-ray showed the pacemaker lead located relatively high in relation to the diaphragm. Echocardiography visualized the pacemaker lead in the left heart chambers (atrium and ventricle), hence confirming its aberrant course. Further, the defect causing its passage to the left heart chambers was a sinus venosus atrial septal defect. The patient reported no complication related to the misplacement of the lead. After a brief period of oral anticoagulation, the lead was inserted into the right ventricle by percutaneous technique. Keywords: pacemaker, lead misplacement, sinus venosus atrial septal defect

Background The arboviruses continue to be a threat to public health and socioeconomic development in sub-Saharan Africa (SSA). Seroprevalence surveys can be used as a population surveillance strategy for arboviruses in the absence of treatment and vaccines for most arboviruses, guiding the public health interventions. The objective of this study was to analyse the seroprevalence of arboviruses in SSA through a systematic review and meta-analysis.Methods We searched PubMed/MEDLINE, Web of Science, Embase, Scopus and ScienceDirect databases for articles published between 2000 and 2022 reporting the seroprevalence of immunoglobulin G (IgG) antibodies to seven arboviruses in various human populations residing in SSA. The included studies were assessed using the checklist for assessing the risk of bias in prevalence studies, and the data were extracted using a standard form. A random effects model was used to estimate pooled seroprevalences. The potential sources of heterogeneity were explored through subgroup analyses and meta-regression. The protocol had been previously registered on International Prospective Register of Systematic Reviews with the identifier: CRD42022377946.Results A total of 165 studies from 27 countries, comprising 186 332 participants, were included. Of these, 141 were low-risk and 24 were moderate-risk. The pooled IgG seroprevalence was 23.7% (17.9–30.0%) for Chikungunya virus, 22.7% (17.5–28.4%) for dengue virus, 22.6% (14.1–32.5%) for West Nile virus, 16.4% (7.1–28.5%) for yellow fever virus, 13.1% (6.4–21.7%) for Zika virus, 9.2% (6.5–12.3%) for Rift Valley fever virus and 6.0% (3.1–9.7) for Crimean–Congo haemorrhagic fever virus. Subgroup and meta-regression analyses showed that seroprevalence differed considerably between countries, study populations, specific age categories, sample sizes and laboratory methods.Conclusion This SRMA provides information on the significant circulation of various arboviruses in SSA, which is essential for the adoption and planning of vaccines. These findings suggest the need to invest in surveillance and research activities on arbovirus in SSA countries to increase our understanding of their epidemiology to prevent and respond to future epidemics.

The increase in flood events observed in West African countries, and often in specific river basins, can be influenced by several factors, including anthropogenic land use and land-cover changes. However, the potential contribution of land cover changes to flood events still needs to be explored, especially in West Africa. Here, the fully coupled atmosphere-hydrology WRF-Hydro system, which comprises an atmospheric model and additionally incorporates the surface, subsurface, overland flow, and channel routing, is used to investigate the potential impact of a land cover change scenario on flood events in the Senegal River basin. The simulation was performed from 2010 to 2020, with a calibration period spanning from 2011 to 2012 and a validation period from 2013 to 2020. Several skill scores, including Nash-Sutcliffe Efficiency (NSE), BIAS, and Kling-Gupta Efficiency (KGE), were utilized to assess the calibration and validation performances. Additionally, two planetary boundary layer schemes (PBL5 and PBL7) were used to determine their associated uncertainty. Our results show that the best calibration results (NSE = 0.70; KGE = 0.83; PBIAS = −7% and BE = 0.67) in the Senegal River basin are obtained with PBL5 when the calibration is performed with a SLOPE parameter 0.03. A similar good performance was also obtained for the validation with NSE = 0.74, KGE = 0.84, and PBIAS = −8%. Likewise, our findings indicate that converting savanna to woody savannas can elevate water resources, with a 2% rise in precipitation and a 4% increase in runoff. This transition also correlates with an increase in moderate flood events (3500–4000 m3/s), a decrease in severe floods (4000–5000 m3/s), and their associated occurrence of extreme floods (>5000 m3/s) in the Senegal River basin.

Introduction: Endoscopic endonasal transsphenoidal surgery is currently the gold-standard therapeutic approach for pituitary adenomas. Although being spread worldwide, the endoscopic endonasal approach for pituitary adenomas is recently implemented in Senegal.This study aimed to report our results and the complications observed in the context of an under-equipped facility. Materials and methods: We conducted a retrospective study including all patients with a pituitary adenoma treated who underwent endonasal transsphenoidal resection under a single endoscopic approach from January 2014 to May 2022, in the Neurosurgery Department of Fann National Hospital Centre, Dakar. All patients were assessed according to clinical, radiological, and endocrinological criteria. They all were operated by the same team with an average follow-up of 24 months. Results: In this series of 180 patients, including 57.7 % women and 42.3% men with a mean age of 44.8 years (extremes of 18 and 76 years), the visual deficit was the most frequent onset symptom (69.4 %), followed by clinical forms of hormone hypersecretion (30.5 %). Twelve cases of pituitary apoplexy and 1 case of incidentaloma were reported. The most frequent tumors were non-functional tumors (61.6 %). Among the functional adenomas, the most frequent was prolactinoma (15.5 %). Regarding tumor size, 75 % were macroadenomas, 15.5 % were microadenomas, and 9.5 % were giants. Cavernous sinus invasion (Knosp grade ≥ 3) and suprasellar extension were noted in 14.4 % and 53.3 %, respectively. The resection was total in 80 % of cases, subtotal in 18.8 %, and partial in 1.2 %. Partial improvement of sight was observed in 91.1% and endocrine hypersecretion remission in 76.6 %. As for complications, the most frequent was transient diabetes insipidus (32.7 %). Conclusion: Despite the scanty resources, our results are similar to the best-reported series and strengthen scientific evidence on the efficacy and safety of performing this technique in an under-equipped setting context.