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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.

This paper presents a model for short-term forecasting of solar potential on a horizontal surface. This study is carried out in to the context of valuing of energy production from photovoltaic solar sources in the Sahelian zone. In this study, Autoregressive Moving Average (ARMA) process is applied to predict global solar potential upon 24 hours ahead. The ARMA (p, q) is based on finding optimum parameters p and q to better fit considered variable (sunshine). Data used for the model calibrating are measured at the station of Ecole Supérieure Polytechnique of Dakar. Records are hourly and range from October 2016 to September 2017. The choice of this model is justified by its robustness and its applicability on several scales through the world. Simulation is done using the RStudio software. The Akaike information criterion shows that ARMA (29, 0) gives the best representation of the data. We then applied a white noise test to validate the process. It confirms that the noise is of white type with zero mean, variance of 1.252 and P-value of about 26% for a significant level of 5%.Verification of the model is doneby analyzing some statistical performance criteria such the RMSE =0.629 (root mean squared error), the R² = 0.963 (Coefficient of determination), the MAE=0.528 (Mean Absolut Error) and the MBE=0.012 (Mean BiasError). Statistics criteria show that the ARMA (29,0) is reliable; then, can help to improve planning of photovoltaic solar power plants production in the Sahelian zone.

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.

Ventricular band cyst is a rare condition in children but can result in severe upper airway obstruction with laryngeal dyspnea or death. The diagnosis should be considered in any stridor in children with previous history of intubation or respiratory infections. We report a case of a 4-year-old girl, received in an array of severe respiratory distress, emergency endoscopy was done, and a large ventricular tape band cyst obstructing the air way was found. Complete excision was made, and postoperative prophylaxis tracheotomy was done. The postoperative course was uneventful with improvement of clinical and endoscopic signs.

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.

A photo-induced fluorescence (PIF) method was developed for the quantification of diclofenac sodium, sodium 2-[2-(2,6-dichloroanilino)phenyl]acetate (NaDCF), in natural waters. Since diclofenac is not naturally fluorescent, its photoconversion under UV irradiation was carried out to produce highly fluorescent photoproduct(s) in various media (water, methanol, isopropanol, acetonitrile, ethyl acetate, dimethyl sulfoxide (DMSO), and a water-isopropanol mixture). The photoproduct responsible for the intense fluorescence of NaDCF in aqueous media was identified as chloro-carbazole by gas chromatography-mass spectrometry (GC-MS). Several PIF parameters were optimized. Using the PIF method, a highly fluorescent diclofenac photoproduct was obtained at λex/λem = 235/360 nm, with optimum fluorescence achieved after 10 min irradiation in a water-isopropanol mixture (90:10 v/v). The limit of detection (LOD) and quantification (LOQ) for diclofenac sodium in this medium were 0.11 ng ml–1 and 0.37 ng ml–1, respectively, with low relative standard deviation (RSD) values. The PIF calibration curves demonstrated good linearity, extending over one to three orders of magnitude, with correlation coefficients (R2) near unity, indicating good reproducibility. Analytical applications of this method to natural water samples yielded satisfactory results, with average recovery rates ranging from 84.77 to 101.72 %.

Tetradymites-based thermoelectric materials and devices have received renewed attention due to their engineering and design flexibility, large scalability, and commercial viability in producing electricity from waste heat for niche applications in small power generation and micro refrigeration. In fact, most commercially available bulk thermoelectric generators (TEGs) are made from tetradymites. In contrast to their bulk counterparts, thin-film vertical TEGs have not been widely adopted. This can be attributable to complexities in design and fabrication methodologies, device measurement challenges, and the hurdle of maintaining a large enough temperature gradient for optimal device performance. In this study, we utilize a facile approach for the design, fabrication, and characterization of tetradymite-based n-type Bi2Te3 and p-type Sb2Te3 single-layer thermoelectric generators, as well as n-type Bi2Te3/Bi2Te2.83Se0.17 and p-type Sb2Te3/Bi0.4Sb1.6Te3 alternating multilayer superlattice TEGs. State-of-the-art characterization techniques were employed to investigate the structural, chemical, and thermoelectric properties of the materials. XRD analysis showed a preferential orientation along the (100) plane with a high intensity peak at 2θ = 25.5°, and XPS spectra exhibited a high-resolution peak at 531.5 eV corresponding to the Bi 4f7/2 core level. The structural data analysis confirmed the dominant metallic phase of the materials as well as their high crystalline nature. Device characterization showed that the multilayer device performed better than the single-layer devices with a recorded voltage, power, and power density of 11 mV, 12 pW, and 15.87 mW/m3 at ΔT = 18 °C, respectively, in comparison to 9.4 mV, 7.8 pW, and 10.31 mW/m3 for the most performing single-layer devices.

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.