Design and modeling of solenoid inductor integrated with FeNiCo in high frequency

In this work, the design and modeling of the solenoid inductor are discussed. The layout of integrated inductors with magnetic cores and their geometrical parameters are developed. The quality factor Q and inductance value L are extracted from the S-parameters and plotted versus frequency. The effect of solenoid inductor geometry on inductance and quality factor are studied via simulation using MATLAB. The solenoid inductor geometry parameters considered are the number of turns, length of the magnetic core, the width of a magnetic core, the gap between turns, the thickness of the magnetic core, the thickness of the coil and oxide thickness of solenoid inductor. The performance of the proposed solenoid inductor integrated with FeNiCo is compared with other solenoid inductors

Simulation of an integrated spiral inductor and inter-digital capacitor in a buck micro converter

In this paper, a novel radiofrequency circuit is designed and developed for an integrated on-chip spiral inductor and inter-digital capacitor of the substrate. Results of extensive simulations concerning the influence of both spiral inductor and inter-digital capacitor geometrical parameters on quality factor value are presented. Two scenarios are considered in the simulation; the first operation of buck converter including an ideal capacitor and inductor and then its operation including an inter-digital capacitor and integrated spiral inductor. For both scenarios, we observed that their respective output voltages as well as their respective output currents present the same time responses

Design and modeling of integrated octagonal shape inductor with substrate silicon in a buck converter

The paper discusses the design and modeling of an integrate octagonal shaped inductor with silicon substrate. A validated equivalent electrical model of the integrated octagonal shaped spiral inductor is developed. The model is used to analyze and evaluate the quality factor and the inductance of the inductor structure proposed under different physical parameters setting. These include the number of turns, spacing between turns and the inner diameter. The simulation results show that an appropriate selection of physic a parameters can achieve an enhanced quality factor and improved inductance. PSIM simulator is used for the implementation of the integrated inductor in a micro buck converter. The simulation results demonstrate that our proposals are very promising approaches for the monolithic integration of DC-DC converters

Epidemiology of resistance and phenotypic characterization of carbapenem resistance mechanisms in Klebsiella pneumoniae isolates at Sahloul University Hospital-Sousse, Tunisia

Objective: To assess the prevalence of ESBL producing and carbapenem resistant Klebsiella pneumoniae isolated from in-come and out-come patients at Sahloul-university hospital.Methods: A retrospective study over a 3 years period (January 2012 and December 2014) focused on 2160 strains of Klebsiella pneumoniae. Statistical analysis was carried out using SPSS program. ESBL detection was performed using a double disc diffusion method and carbapenemase detection was realized by Rosco-Disk kit.Results: A total of 2160 Klebsiella pneumoniae strains were isolated during the period of the study, 26.2% (n=566) were ESBL-producers and 15.8% (n=342) showed resistance to carbapenem. The wards most affected by these strains were basically urology and intensive care units. Eighty four percent of studied strains (203/241) were resistant to temocillin, which correlate with the production of a class D (OXA-48-like) carbapenemase and 7% (17/241) showed sensitivity to EDTA and dipicolinic acid, which indicate the production of metallo-enzyme. The rate of resistance to colistin remains low.Conclusion: Resistance of Enterobacteriaceae, including K. pneumoniae, to third generation cephalosporins (3rd GC) and carbapenem through the mechanism of ESBL and carbapenemases production is becoming increasingly worrying. This suggests a morerational use of antibiotics, as well as the rigorous application of hygiene measurement.Keywords: Klebsiella pneumoniae, epidemiology, ESBL, carbapenemase, phenotypic screening

Evolutions and threats to land management in the peri-urban area of the city of Sidi Bel Abbes (Algeria) - an analysis based on spatial cadastral data

Sidi Bel Abbes, the capital of Mekerra, a city of the interior plain, where agricultural land has experienced urban spillover at the expense of peri-urban land. The accelerated sprawl between 1987 and 2019 is expressed by threats to peri-urban state land, the pressure on agricultural activity on the peripheries of the city, and a relaxation of respect for planning policies at the local level. How can peri-urban land be better protected, and consequently encourage agricul-tural use, without abandoning it? This work analyses the legal nature of the land taken for the benefit of urban construction and characterizes its spread using Landsat multispectral satellite data. Our approach is based on the following question: Does urban sprawl impact the man-agement of land and its legal nature? What is the future of this land in the face of current threats and future planning and urban development orientations? The cartographic analyses with the actual practices of the different social groups in the field have made it possible to evaluate the relationship between agricultural policy, and implementation and to situate the conflicts or threats about urban sprawl. The north of the city of Sidi Bel Abbes (cadastral sec-tion n°3, 324.74 ha), is where 45% of state land is acquired for building purposes. A reorienta-tion of the peri-urban land is currently presented by a new management mode of an individual type, as a means of freezing and/or preserving the land: the creation of hedges and fences, the introduction of arboriculture (olive tree or other). Observations on site made it possible to ex-plain these practices, which are at the origin of these current representations. The crops prac-tice is linked to the profit drawn on compensations, and the plantations are a source of good remuneration

Effet de l'orientation des plis sur la rupture intralaminaire des stratifiés (2D) (Polyester/tissu de verre)

L'étude de la rupture des stratifiés fissurés n'a pas trouvé jusqu'à présent une grande extension dans la littérature. En raison de leur nature anisotrope il est difficile d'envisager entièrement leurs caractéristiques et comportement mécaniques, en particulier s'ils sont produits avec des architectures compliquées, comme dans le cas des renforts tissés. Ce travail a été réalisé pour fournir plus de détails sur l'effet de l'orientation et l'emplacement des couches sur la propagation de la fissure dans les stratifiés (2D). Les résultats montrent que l'orientation a un effet significatif sur l'amorçage et la propagation de fissure. L'amorçage et le développement de la zone d'endommagement (ZE) sont étudiés en utilisant la technique de corrélation d'image digitale (CID)

Epidemiology of resistance and phenotypic characterization of carbapenem resistance mechanisms in Klebsiella pneumoniae isolates at Sahloul University Hospital-Sousse, Tunisia

Objective: To assess the prevalence of ESBL producing and carbapenem resistant Klebsiella pneumoniae isolated from in-come and out-come patients at Sahloul-university hospital. Methods: A retrospective study over a 3 years period (January 2012 and December 2014) focused on 2160 strains of Klebsiella pneumoniae. Statistical analysis was carried out using SPSS program. ESBL detection was performed using a double disc diffusion method and carbapenemase detection was realized by Rosco-Disk kit. Results: A total of 2160 Klebsiella pneumoniae strains were isolated during the period of the study, 26.2% (n=566) were ESBL-producers and 15.8% (n=342) showed resistance to carbapenem. The wards most affected by these strains were basically urology and intensive care units. Eighty four percent of studied strains (203/241) were resistant to temocillin, which correlate with the production of a class D (OXA-48-like) carbapenemase and 7% (17/241) showed sensitivity to EDTA and dipicolinic acid, which indicate the production of metallo-enzyme. The rate of resistance to colistin remains low. Conclusion: Resistance of Enterobacteriaceae, including K. pneumoniae, to third generation cephalosporins (3rd GC) and carbapenem through the mechanism of ESBL and carbapenemases production is becoming increasingly worrying. This suggests a more rational use of antibiotics, as well as the rigorous application of hygiene measurement. DOI: https://dx.doi.org/10.4314/ahs.v19i2.24 Cite as: Messaoudi A, Mansour W, Jaidane N, Chaouch C, Bouja\ue2far N, Bouall\ue8gue O. Epidemiology of resistance and phenotypic characterization of carbapenem resistance mechanisms in Klebsiella pneumoniae isolates at Sahloul University hospital-Sousse, Tunisia. Afri Health Sci.2019;19(2): 2008-2020. https://dx.doi.org/10.4314/ahs.v19i2.2

Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020

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

Simulation of an integrated spiral inductor and inter-digital capacitor in a buck micro converter

In this paper, a novel radiofrequency circuit is designed and developed for an integrated on-chip spiral inductor and inter-digital capacitor of the substrate. Results of extensive simulations concerning the influence of both spiral inductor and inter-digital capacitor geometrical parameters on quality factor value are presented. Two scenarios are considered in the simulation; the first operation of buck converter including an ideal capacitor and inductor and then its operation including an inter-digital capacitor and integrated spiral inductor. For both scenarios, we observed that their respective output voltages as well as their respective output currents present the same time responses