Optimal Control Technique of an Induction Motor

The squirrel cage induction motor (IM) has many advantages over other types of electric technique (FOC), classical direct torque control (DTC), and direct torque control with space vector modulation (DTC-SVM) is carried out. The objective of this paper is to decouple the mechanical quantities such as torque and flux in a way similar to the DC motor control. And also to minimize the torque and flux modulation of the IM. Torque oscillations can cause mechanical resonances and consequently acoustic noise, hence damaging the machine. Reducing the switching frequency significantly minimizes switching losses. The DTC-SVM control technique improves the performance of conventional DTC, which is characterized by low torque and flux modulation as well as a fixed switching frequency. Simulation results in MATLAB show that torque and current ripples are reduced with the improved DTC. DTC-SVM used for the traction control system is easy to implement in digital systems and also allows to move the photovoltaic panels according to the position of maximum sunshine to extract the maximum energy with high efficiency from the system

Profile of patients with HPV infection at the regional hospital of Saint-Louis, Senegal

Background: Objectives of current study was to define the sociodemographic characteristics of patients, to determine the frequency of HPV infection at the CHRSL and to describe factors associated with HPV infection. Methods: This was a prospective cross-sectional study conducted in the gynecology-obstetrics department of the Saint Louis Regional Hospital Center from November 11, 2019 to November 11, 2021, a period of 24 months. We studied sociodemographic, clinical and test results characteristics. Samples were taken from patients in the gynaecological position using a dedicated kit (cytobrush and tube). Viral research was carried out using the Atila Biosystems device for amplification and detection of viral DNA. This test genotypes HPV 16, 18 and 45, and detects 12 other HR HPVs (31, 33, 35, 39, 51, 52, 56, 58, 59, 66 and 68) simultaneously using three probes labelled with different fluorophores. Analysis was performed using Epi-Info software and Excel 2010. Results: The study population comprised 128 patients. The mean age of the patients was 41.95 years, with extremes of 23 and 70 years. They were married (92.97%) and housewives (46.88%). Almost all patients (77.34%) were genitally active. The average age at marriage was 21.78 years, and polygamous households predominated (53.91%). The average age at first intercourse was 20.05 years. The average age at first pregnancy was 21.78. Over (57.81%) of patients had at least two partners. Incense was used in 97.66% of cases. The viral HPV test was positive in (38.28%) of patients. High-risk papillomaviruses were the most common, at 63.27%. Colposcopy was performed in 17.19%; normal and satisfactory in (63.64%) of patients, with 22.27% of cervical biopsies, and histology showed one CIN2 and two CIN3. Therapeutically, one thermoablation and two hysterectomies were performed. Conclusions: HPV viral typing in primary screening for cervical cancer offers opportunities and remains realistic and feasible in less developed countries such as Senegal, despite modest resources

Evaluation of the use of birth control followed in women's hospital regional Saint Louis (Senegal) in 2014

Background: To evaluate the use of contraceptive methods among women followed at Saint Louis Health Centre.Methods: This was a descriptive cross-sectional study of all recue clients in the Obstetrics and Gynecology department of the Regional Hospital of St. Louis. She ran from 1 January 2014 to 31 December 2014, 12 months.Results: The mean age was 28.8 years. The most common demographic characteristics were the Wolof ethnic group (64.5%), married the marital status (97.9%), they were not in school in 46.3%. The main sources of information on the use of contraception were health workers in 80.3%, friends and relatives (8.5%) followed by husbands (2.5%), the media represented 6 0% and 0.1% posters. The injection method was the most used method (42.8%) followed by implants (36.2%), pills (14.9%) and tubal ligation (4.4%). The IUD was the least used method with 1.7% of use. The main reasons given by women were spacing births (70.6%), to avoid unwanted pregnancy (3.90%), avoid early pregnancies (1.20%) and of other unspecified reasons in 24.3%. In this study, no accidental pregnancy was reported. Indeed, 79.4% of women had respected the monitoring schedule of monitoring visits. They had abandoned contraception in 23.5%.Conclusions: This study shows the achievements and shortcomings in relation to the nature and completeness of the information provided. Strengthening the awareness and training will reduce missed opportunities for family planning, and indirect; reduce the rate of unmet need for FP in our country

Antibiotic susceptibility profile of Streptococcus pneumoniae isolated from acute respiratory infection in Dakar: a cross sectional study

Streptococcus pneumoniae is a pathogen causing pneumonia, meningitis, otitis and bacteraemia. Nowadays, S. pneumoniae is developing antibacterial resistance, particularly for those with reduced susceptibility to penicillin. The objective of this study was to assess the susceptibility profile of S. pneumoniae strains isolated from acute respiratory infections (ARIs) in children younger than 5 years of age in Dakar, Senegal. S. pneumoniae strains were isolated from broncho-alveolar lavages (BALs), nasopharyngeal swabs, and middle ear secretion from children in the Paediatric Department of Abass Ndao University Teaching Hospital and Paediatric Department of Roi Baudouin Hospital in Dakar, Senegal. The strains were cultivated on Columbia agar supplemented with 5% of horse blood and gentamicin (6 mg/L). Antibiotic susceptibility testing was performed using E-test method. A total of 34 strains of S. pneumoniae were isolated and identified in this study, among them 7 strains (20.58%) showed penicillin-resistance. Antibiotics such as amoxicillin/clavulanic acid (MIC90=0.036 μg/mL), cefuroxim (MIC90=0.38 μg/mL), cefixim (MIC90=1.5 μg/mL), as well as macrolides (azithromycin MIC90=1.5 μg/mL, clarithromycin MIC90=0.125 μg/mL) and fluoroquinolone (levofloxacin MIC90=1 μg/mL, ofloxacin MIC90=2 μg/mL) were mostly active. However, all S. pneumoniae strains were resistant to sulfamethoxazole/trimethoprim (MIC90: 32 μg/mL). Except of S. pneumoniae strains penicillin-resistance or reduced susceptibility, most strains were susceptible to β-lactams antibiotics commonly used in ARI treatment. Continuous surveillance of antimicrobial resistance patterns of pneumococcus strains is still crucial for effective control of ARIs in children

Cross-cultural comparison of mental illness stigma and help-seeking attitudes: a multinational population-based study from 16 Arab countries and 10,036 individuals

BackgroundThere is evidence that culture deeply affects beliefs about mental illnesses\u27 causes, treatment, and help-seeking. We aimed to explore and compare knowledge, attitudes toward mental illness and help-seeking, causal attributions, and help-seeking recommendations for mental illnesses across various Arab countries and investigate factors related to attitudes toward help-seeking.MethodsWe carried out a multinational cross-sectional study using online self-administered surveys in the Arabic language from June to November 2021 across 16 Arab countries among participants from the general public.ResultsMore than one in four individuals exhibited stigmatizing attitudes towards mental illness (26.5%), had poor knowledge (31.7%), and hold negative attitudes toward help-seeking (28.0%). ANOVA tests revealed a significant difference between countries regarding attitudes (F = 194.8, p \u3c .001), knowledge (F = 88.7, p \u3c .001), and help-seeking attitudes (F = 32.4, p \u3c .001). Three multivariate regression analysis models were performed for overall sample, as well as Palestinian and Sudanese samples that displayed the lowest and highest ATSPPH-SF scores, respectively. In the overall sample, being female, older, having higher knowledge and more positive attitudes toward mental illness, and endorsing biomedical and psychosocial causations were associated with more favorable help-seeking attitudes; whereas having a family psychiatric history and endorsing religious/supernatural causations were associated with more negative help-seeking attitudes. The same results have been found in the Palestinian sample, while only stigma dimensions helped predict help-seeking attitudes in Sudanese participants.ConclusionInterventions aiming at improving help-seeking attitudes and behaviors and promoting early access to care need to be culturally tailored, and congruent with public beliefs about mental illnesses and their causations

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Poly[[hexaaquasesqui(μ-benzene-1,2,4,5-tetracarboxylato)dicopper(II)disodium] monohydrate]

In the title compound, {[Cu2Na2(C10H2O8)1.5(H2O)6]·H2O}n, the Cu2+ ion is hexacoordinated by five O atoms from benzene-1,2,4,5-tetracarboxylate (btec4−) ligands and one water molecule. The Na+ ion is also hexacoordinated, by four O atoms from btec4− ligands and two water molecules. One of the two btec4− molecules sits on a crystallographic inversion centre. CuO6 and NaO6 octahedra are connected, forming bi-dimensional layers. These layers, which extend parallel to the ac plane, are further interconnected by μ10- or μ11-bridging btec4− ligands and by O—H...O hydrogen bonds, involving both btec4− ligands and water molecules, forming a three-dimensional network

Simulation et réalisation d’un contrôleur de batterie solaire à base de PIC16F876

International audienceL’accumulateur est un élément fondamental d’un système photovoltaïque. Il n’est pas concevable de réaliser une alimentation digne de ce nom à base de panneau solaire sans lui adjoindre une batterie tampon se substituant au panneau lorsque le soleil fait défaut. Les charges et décharges des batteries non contrôlées perturbent le bon fonctionnement de la batterie. Ces perturbations peuvent considérablement réduire la durée de vie et le bon fonctionnement de la batterie. Ce travail consiste à concevoir et à réaliser un contrôleur afin de maintenir une batterie d'accumulateurs à un état de charge élevé, sans la surcharger démesurément