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This paper aims to directly denoise option price while adhering to the no–arbitrageconditions. To achieve our goal, we propose the Gaussian Process (GP) method thatentails training the GP on noisy data of option prices as a linear function of the pairof maturity and strike. Utilizing the GP approach not only allows for removing noiseson the option price surface by verifying the no–arbitrage conditions but also is a proba-bilistic approach that allows quantifying the uncertainty on the quantity of interest byconstructing confidence bands around the estimate. The GP further permits forecastingout-of-the-sample prices without needing to compute the risk-neutral density of the op-tion price surface. To investigate the efficiency of GP in removing the noise from optionprices, we tested it on a simulated dataset. The overall MSE between the computedBlack–Scholes prices and the GP denoised is 0.10, and between the Black–Scholes pricesand the noisy prices is 2.21 - a 95.33% noise removal. The curves of the graphs for thedenoised prices are all convex and non–increasing in strikes, upholding the no–arbitrageconditions. To our best knowledge, the challenge of directly denoising option prices hasled to little interest in this area, and our work is the first to undertake this task

This research studies the capability of the Weather Research and Forecasting model coupled with the Chemistry/Aerosol module (WRF-Chem) with and without parametrization to reproduce a dust storm, which was held on 27th June 2018 over Sahara region. The authors use satellite observations and ground-based measurements to evaluate the WRF-Chem simulations. The sensitivities of WRF-Chem Model are tested on the replication of haboob features with a tuned GOCART aerosol module. Comparisons of simulations with satellite and ground-based observations show that WRF-Chem is able to reproduce the Aerosol Optical Depth (AOD) distribution and associated changes of haboob in the meteorological fields with temperature drops of about 9 °C and wind gust 20 m·s–1. The WRF-Chem Convection-permitting model (CPM) shows strong 10-meter winds induced a large dust emission along the leading edge of a convective cold pool (LECCP). The CPM indicates heavy dust transported over the West African coast (16°W-10°W; 6°N-21°N) which has a potential for long-distance travel on 27th June between 1100 UTC and 1500 UTC. The daily precipitation is improved in the CPM with a spatial distribution similar to the GPM-IMERG precipitation and maximum rainfall located at the right place. As well as raising a large amount of dust, the haboob caused considerable damage along its route.

Toxoplasmosis in immunocompromised patients results in either reactivation of latent toxoplasmosis or acute infection. In the framework of the kidney transplantation program in Senegal, the serological screening of potential pre-transplant and transplanted patients can prevent the disease. This study aimed to assess the seroprevalence of toxoplasmosis in a cohort of hemodialysis patients, candidates for kidney transplantation. To this end, a multicentre cross-sectional study was conducted in 2020 in six dialysis units from five regions. Blood samples and sociodemographic data were collected from each patient. IgG and IgM against T. gondii antibodies were assessed by a chemiluminescent method using Architect ci4100, and statistical analysis was performed using R software. Overall, 211 hemodialysis patients aged from 18 to 77 years were enrolled. The mean age was 42.62 years ± 13.6, and the sex ratio M/F was 1.24. The overall seroprevalence of T. gondii was 41.7%, with the highest value being recorded in the region of Kaolack (44.4%). Patients aged over 60 years were more typically infected, at a proportion of 56.0%. Regarding sex, males elicited a higher prevalence (44.4.%) than females did. Patients of an upper socioeconomic status were less affected, and contact with cats was not associated with toxoplasmosis. By education level, the illiterate group was most affected one. Overall, this first study of toxoplasmosis among Senegalese hemodialysis patients indicates high seroprevalence.

The relatively small panel cointegration literature on the dynamics between FDI and income inequality predominantly finds that FDI will reduce income inequality in the long-run in developed countries. However, we point out an important technical oversight in the literature. Not accounting for cross-section dependence in panel data methodologies may yield unreliable results. Expanding on the work of Herzer and Nunnenkamp [(2013). Inward and outward FDI and income inequality: Evidence from Europe. Review of World Economics, 149(2), 395-422. https://doi.org/10.1007/s10290-013-0148-3], who pioneered the use of panel cointegration in the European context, we obtain different results when we account for cross-section dependence and employ economic procedures robust to it. Using a panel containing 16 OECD countries (1979-2017), 2 income inequality measures, and 4 FDI measures, we begin by showing strong evidence for the existence of cross-section dependence. Then, using second-generation econometric procedures, we do not find any evidence for a cointegrating relationship between inward FDI and income inequality. We do find evidence that outward FDI is cointegrated with income inequality; however, contrary to the main results of the literature, we find that it widens the income gap in the long-run. Additionally, our results support the view that fiscal policy is an important tool to reduce income inequality.

A post-acne hyperpigmentation index (PAHPI) has been developed in the United States to better compare therapeutic modalities. Our aim in this study was to validate the PAHPI score in patients with skin type VI from sub-Saharan Africa.The study was conducted in Dakar, Senegal. Twenty-one patients with Fitzpatrick skin type VI, aged 17 to 55 years, presenting hyperpigmentation secondary to acne were included. Ongoing use of skin bleaching products or acne treatments was allowed. Four trained dermatologists rated the patients using the PAHPI. A narrow-band reflectance spectrophotometer (Mexameter MX-18, Cologne, Germany) was used to measure the degree of pigmentation of involved and adjacent skin on 6 representative facial lesions.The average inter-rater reliability (weighted Kappa) showed substantial agreement for intensity (0.67), moderate agreement for number (0.53) and fair agreement for lesion size (0.28). Inter-rater reliability for the total PAHPI was excellent for both day 1 and day 2 (interclass correlation coefficient of 0.87 and 0.85, respectively; P0.0001). Intra-rater reliability for total PAHPI ranged from 0.83 to 0.93 (P0.0001). PAHPI scoring thus demonstrated excellent reliability both between and within raters. The association was moderate to substantial for all raters on both days (range for rho on day 1: 0.531 to 0.815; range for rho on day 2: 0.448 0.762). The correlations between the Mexameter (Courage and Khazaka) measurements and PAHPI scores showed moderate to substantial agreement.Although tested primarily in African American women to date, PAHPI is also valid for patients from sub-Saharan Africa.

Background: Rotavirus infection is the most important cause of infectious, severe and dehydrating diarrhea and death in children aged 5 and under and continues to have a significant impact on child morbidity and mortality in our countries. The aim of this study was to retrospectively determine prevalence of rotavirus and adenovirus in patients presenting with gastroenteritis symptoms and the distribution of pathogens according to gender, age and season. Materials and Methods: Stool samples received at the medical microbiology laboratory between January 2018 and December 2022 were evaluated for rotavirus/adenovirus antigen with BIOSYNEX Rotavirus/Adenovirus BSS kit (BIOSYNEX, Switzerland). Results: Rotavirus was detected in 36 (6.96%) of the 517 stool samples evaluated and 16 (3.09%) samples were positive for adenovirus. Co-infection was detected in 10 samples (1.93%). Prevalence of rotavirus and adenovirus was 12.22% (28/229) and 4.80% (11/229) respectively in children aged 0-12 months. Our results showed a significant difference between the patients among the three study groups (rotavirus, adenovirus and mixed) with regard to their age categories. Regarding the monthly distribution, the highest detection rate of rotavirus gastroenteritis was found between the months of September (12.28%) and February (14.89%). Adenoviruses were detected continuously over a period from June to December with a significant difference (p

The study compared the syntactic complexity and the use of logical connectors in summaries written in French by two groups of students: speakers of French as first language (L1) and peers in a French-immersion program (L2) from grade nine to university. Both L1 and L2 groups of university students demonstrated more general complexity in their written summaries than less mature writers. However, the use of phrasal elaboration was apparent just at the upper secondary and university levels with L1 students. Both groups generally tend to overuse causal connectors while underusing additive and adversative connectors compared to the author’s use in the source text. Yet both groups employ significantly more adversative connectors just at the post-secondary level. The only difference observed between L1 and L2 writers was in the diversity of connector words used in the summary, with the former group using a richer, more diverse vocabulary. Several measures for succinctness differentiated L1 and L2 students in early secondary with the latter group condensing the source text less than L1 students. Correlation analysis suggested that many measures of syntactic complexity and connector use are inextricably linked.

The intersecting identities of those identifying with multiple minorities, such as 2SLGBTQ + and ethnolinguistic minorities, bring individuals to have unique experiences, especially concerning health and wellness. This topic is particularly poorly understood among French-speaking official language minority 2SLGBTQ + populations in Canada. Hence, this study was conducted to generate insights into their needs and experiences, through the lens of intersectionality. This quantitative community-based study, a first of its kind in Western Canada, describes the sociodemographic profile, experiences of discrimination and stigmatisation, and needs and challenges pertaining to mental health and social supports of this double minority group. Data were obtained by an online survey conducted in the Canadian province of Manitoba in June 2020. The participant sample was largely homogenous: most were under the age of 55 years, white, educated, and from urban areas. Many reported experiencing dual marginalisation, feeling unaccepted by both of their minority communities (Francophone and 2SLGBTQ+). A sense of isolation, as well as a lack of social connectedness and psychological support, were often reported. Social initiatives and mental health support within environments proactively affirming of the official language of the minority and inclusive of diverse 2SLGBTQ + identities are needed.

BackgroundHaving a consolidated, geolocated list of all facilities in a country – a “master facility list” (MFL) – can provide critical inputs for health program planning and implementation. To the best of our knowledge, Senegal has never had a centralized MFL, though many data sources currently exist within the broader Senegalese data landscape that could be used to work toward building a full MFL.Main textWe collated 12,965 facility observations from 16 separate datasets and lists in Senegal, and applied matching algorithms, manual checking and revisions as needed, and verification processes to identify unique facilities and triangulate corresponding GPS coordinates. Our resulting consolidated facility list was a total of 4,685 facilities with 51.5% having at least one GPS coordinate (n=2,414). Key challenges included accounting for variable spelling across datasets, distinguishing between facility type changes (e.g., health huts being upgraded to health posts with the same name) and separate facilities that shared the same name, GPS verification, among others.ConclusionDeveloping approaches to leverage existing data for MFL establishment can help bridge data demands and inform more targeted approaches for completing a full facility census based on areas and facility types with the lowest coverage. Going forward, it is crucial to ensure routine updates of current facility lists, and to strengthen government-led mechanisms around such data collection demands and the need for timely data for health decision-making.

This commentary brings together theory, evidence and lessons from 15 years of gender and HRH analyses conducted in health systems in six WHO regions to address selected data-related aspects of WHO’s 2016 Global HRH Strategy and 2022 Working for Health Action Plan. It considers useful theoretical lenses, multi-country evidence and implications for implementation and HRH policy. Systemic, structural gender discrimination and inequality encompass widespread but often masked or invisible patterns of gendered practices, interactions, relations and the social, economic or cultural background conditions that are entrenched in the processes and structures of health systems (such as health education and employment institutions) that can create or perpetuate disadvantage for some members of a marginalized group relative to other groups in society or organizations. Context-specific sex- and age-disaggregated and gender-descriptive data on HRH systems’ dysfunctions are needed to enable HRH policy planners and managers to anticipate bottlenecks to health workforce entry, flows and exit or retention. Multi-method approaches using ethnographic techniques reveal rich contextual detail. Accountability requires that gender and HRH analyses measure SDGs 3, 4, 5 and 8 targets and indicators. To achieve gender equality in paid work, women also need to achieve equality in unpaid work, underscoring the importance of SDG target 5.4. HRH policies based on principles of substantive equality and nondiscrimination are effective in countering gender discrimination and inequality. HRH leaders and managers can make the use of gender and HRH evidence a priority in developing transformational policy that changes the actual conditions and terms of health workers’ lives and work for the better. Knowledge translation and intersectoral coalition-building are also critical to effectiveness and accountability. These will contribute to social progress, equity and the realization of human rights, and expand the health care workforce. Global HRH strategy objectives and UHC and SDG goals will more likely be realized.

Research collaboration has become a major research topic in the social sciences. While this literature has mainly focused on collaborative dynamics in the Global North, more recent studies have examined these dynamics within the Global South. This article expands the scope of analysis by comparing the level of co-publications by Global South-based scholars with Global South-based colleagues and that between academics at Global South institutions and researchers in Global North universities. It shows that academic partnerships within the Global South are less common than instances of collaboration between the Global South and Global North. The relatively weak Global South collaborative dynamics are at odds with most Global South leaders’ encouragement of partnerships between scholars within the South. The article also demonstrates that collaboration seems to be largely informed by linguistic commonality and historical (colonial) relations of dependency. Contrary to expectations that US-based academics would be the primary partners for Global South academics due to US hegemony, the latter are more likely to collaborate with colleagues in European countries, more specifically countries that colonised their countries.

The magneto-transport equation relating to the density of photogenerated minority carriers in the (p) base of the (n+/p/p+) solar cell illuminated by monochromatic light in frequency modulation, is solved. The diffusion coefficient of the minority carriers in the base, placed under temperature and magnetic field variation, passes through a maximum, at the double resonance points, in temperature and at the frequency of the cyclotron. The photocurrent is reproduced as a function of the recombination velocity at the junction, for the maximum values of the diffusion coefficient. The expressions of the minority carriers ’recombination velocity on the rear side are deduced and their graphical representation gives the optimum thickness, specific to a high absorption coefficient, for the maximum values of the diffusion coefficient. The results obtained from the optimum thickness are modelled and analyzed, in favor of a reduction of silicon material, for the development of economical solar cells.

The European Nucleotide Archive (ENA; https://www.ebi.ac.uk/ena), maintained by the European Molecular Biology Laboratory's European Bioinformatics Institute (EMBL-EBI), offers those producing data an open and supported platform for the management, archiving, publication, and dissemination of data; and to the scientific community as a whole, it offers a globally comprehensive data set through a host of data discovery and retrieval tools. Here, we describe recent updates to the ENA’s submission and retrieval services as well as focused efforts to improve connectivity, reusability, and interoperability of ENA data and metadata.

En Afrique, notamment dans les zones rurales, la modicité des moyens de subsistance prédispose les populations à se détourner des médicaments modernes onéreux et souvent inaccessibles. Le coût et la disponibilité de ces principes actifs modernes les rendent quasiment, hors de portée d’une grande majorité des populations. La phytothérapie à base d'extraits de plantes est une pratique courante dans la médecine traditionnelle africaine. C’est dans ce cadre que s’inscrit ce travail, dont l’objectif était de lister les vertus thérapeutiques et alimentaires d’Annona senegalensis. Ainsi, une étude ethnobotanique, sous forme d’un questionnaire, a été menée dans quatre (4) régions du Sénégal à la fin de l’hivernage 2020. Les résultats ont montré que les feuilles sont les plus sollicitées (70,70%), suivies de la tige pour 47,80% des personnes interrogées. Ces organes sont utilisés essentiellement dans le traitement de maladies diverses telles que : les maux de tête (75,70%), la diarrhée (70,20%), les maux de ventre (51,20% et la dysenterie 40,00%. La macération (75,50%), la décoction (46,20%) et la pulvérisation (20,10%) sont les modes de préparation les plus fréquents. Les fruits ovoïdes sphériques jusqu’à 4 cm de diamètre, jaune orangé à maturité, avec une pulpe jaunâtre, sucrée sont consommés dans 94,2% des cas, mais ne font l’objet d’aucune transformation. Les graines, de 8 à 11mm de diamètre, ne sont pas consommées au Sénégal. Ces résultats constituent un apport dans la mise en place de données ethnobotaniques sur Annona senegalensis qui devraient mener vers des investigations phytochimiques et pharmacologiques. In Africa, especially in rural areas low livelihoods predispose people to turn away from expensive and often inaccessible modern drugs. The cost and the availability of these modern active substances make them almost beyond the reach of a large majority of populations. Phytotherapy based on plant extracts is a common practice in traditional African medicine. It is in this context that this work fits, the objective of which, was to list the therapeutic and nutritional virtues of Annona senegalensis. Thus, an ethnobotanical study in the form of a questionnaire was carried out in four (4) regions of Senegal at the end of the 2020 rainy season. The results showed that the leaves are the most solicited (70.70%), followed by the stem for 47.80% of respondents. These organs are used mainly in the treatment of various diseases such as: headaches (75.70%), diarrhea (70.20%), stomach aches (51.20% and dysentery 40%. Maceration (75.5%), decoction (46.2%) and pulverization (20.10%) are the most frequent methods of preparation. Spherical ovoid fruits up to 4 cm in diameter, orange-yellow when ripe, with a yellowish, sweet pulp are consumed in 94.20% of cases, but are not processed. The seeds, 8 to 11 mm in diameter, are not consumed in Senegal. These results constitute a contribution to the establishment of ethnobotanical data on Annona senegalensis which should lead to phytochemical and pharmacological investigations.

In the title compound, [Tb(H2L)2(H2O)3].3Cl.4(H2O).(C2H5OH), the Tb3+ is nine-coordinated in a distorted monocapped square antiprismgeometry by four nitrogen atoms, two oxygen atoms from the ligand molecules of the tridentate N,N'-1,5-bis(pyridylmethylidene) carbonohydrazone) (H2L) and three oxygen atoms of coordinating water molecules. The structure of the complex was elucidated by X-ray diffraction analysis. Suitable crystals were grown by slow evaporation of ethanol solution. The compound crystallizes in the triclinic crystal system with a space group of Pī. The asymmetric unit of the compound contains two neutral ligand molecules, oneterbium ion, three coordinated water molecules, five and half uncoordinated water molecules and one uncoordinated ethanol molecule. In the crystal, the complex cations are linked by hydrogen bonds into layers. These layers, chloride anions and non-coordinating water molecules are connected by O—H···O, O—H···N, O—H···Cl, N—H···O, N—H···Cl and C—H···Cl hydrogen bonds into a three-dimensional structure.

Black medical students have been consistently underrepresented in Canadian medical schools, and data on the impact of discrimination on their medical education remain limited. In this cross-sectional study, we aimed to investigate the experiences of Black medical students through the Black Medical Students' Association of Canada (BMSAC).We developed a 63-item instrument around the domains of inclusion and diversity, wellness, discrimination, career advancement and diversity in medical education. The anonymous web-based questionnaire was sent to 128 medical students and first-year residents from all 17 Canadian medical schools via the BMSAC listserv. We obtained frequencies for demographic data and self-reported experiences.We received 52 responses. Of respondents, 59% had at least 1 personal encounter with discrimination in medical school. Discrimination was experienced in both clinical and academic contexts, notably from patients, peers and hospital staff. Students further along in their medical training were more likely to endorse having experienced discrimination in medical school. Most respondents had positive experiences with academic and clinical inclusion, as well as resiliency in the face of discrimination. However, most respondents had negative experiences relating to reporting discrimination, their well-being, career advancement, sentiments of minority tax and low diversity in medical education.We found that discrimination has important implications on the learning experiences of Black medical students surveyed from the BMSAC. This directly challenges the notion that Canadian medical schools are impervious to racism and highlights the need for advocacy and systemic changes to eliminate institutional racism.