FC/Battery Power Management for Electric Vehicle Based Interleaved DC-DC Boost Converter Topology

International audienceDue to the fact that the environmental issues have become more serious recently, interest in renewable energy systems, such as, fuel-cells (FCs) has increased steadfastly. Among many types of FCs, proton exchange membrane FC (PEMFC) is one of the most promising power sources due to its advantages, such as, low operation temperature, high power density and low emission. However, using only PEMFC for electric vehicle may not be feasible to satisfy the peak demand changes especially during accelerations and braking. So, hybridizing PEMFC and an energy storage system (ESS) decreases the FC cost and improves its performance and life. Battery (B) appears to be the most powerful candidate to hybridize with PEMFC for vehicular applications. Therefore, the performance of PEMFC/B hybridization is limited considerably by the performance of the converter. Thus, a suitable dc-dc converter topology is required. Various isolated and nonisolated converter topologies for FC applications have been proposed in literature. The objective of this study is to design and simulate a fuel cell - interleaved boost dc-dc converter (FC-IBC) for hybrid power systems in electric vehicle application, in order to decrease the FC current ripple. Therefore Energetic efficiency can also be improved. A control strategy capable of determining the desired FC power and keeps the dc voltage around its nominal value by supplying propulsion power and recuperating braking energy is designed and tested with an urbane electric vehicle model

An Improved MPPT Interleaved Boost Converter for Solar Electric Vehicle Application

International audienceAn interleaved boost dc/dc converter is developed featuring smaller input/output filters, faster dynamic response and lower device stress than conventional designs, for solar electric vehicle (SEV) applications. The converter is connected between the photovoltaic power generation and dc bus in a multisource energy storage system of a SEV. Typically, interleaved converters require a current control loop to reduce the input current ripples, the output voltage ripples, and the size of passive components with high efficiency. A Maximum Power Point Tracking (MPPT) controller for a Photovoltaic (PV) solar system associated to backup source (Battery) guarantees an uninterrupted power supply and assist the propulsion of the vehicle during transients and recover energy during regenerative braking. The design, construction, and testing of an experimental hardware p rototype is presented, with the test results included

The role of citizenship values and civic education for the development of social skills at secondary schools

This paper seeks to empirically investigate the question of citizenship values and civic education in Moroccan secondary schools. It undertakes a comparative study based on an interdisciplinary approach in order to measure the presence of these values in Physics and English educational practices. The study is realized via a questionnaire administered to and interviews conducted with practicing teachers of Physics and English throughout different schools in Morocco. Data collection and analysis were performed by adopting a statistical descriptive method. The study is accomplished by targeting a number that reached 84 teachers in both disciplines. Our results demonstrate that teachers have different conceptions concerning values and they show less interest in implementing those values in the teaching/learning operation. Physics teachers believe that Physics as a purely scientific discipline cannot lead itself to integrating citizenship values and they can be integrated only in Humanities disciplines. Furthermore, we find that teachers not only never benefited from a basic or in-service training but also professional interaction among them about those values is very lacking. Besides, a considerable number of respondents agree that citizenship values are decreasing among learners. In this sense, majority of respondents suggest that training, motivation and well-prepared institutional strategies are fundamental prerequisites to overcome those difficulties.

Single Level Lumbar Disk Herniation: Conventional Discectomy versus Interbody Fusion with Bilateral Pedicular Fixation

OBJECTIVE: The objective of the study was to compare between the conventional discectomy and the interbody fusion with bilateral pedicular screw fixation in the management of single level lumbar disk herniation. METHODS: This is a prospective study done on 50 patients (25 in each group) at Cairo University Hospitals in the period between October 2018 and June 2019 fulfilling the inclusion criteria. Diagnosis was made clinically with history (low back pain and sciatica),examination (motor power assessment, straight leg raising test), and radiological findings (MRI, CT and X-ray lumbar spine). The pain status (VAS) was pre and postoperatively evaluated and followed up every 3 months for 1 year. RESULTS: The study included 50 patients (25 in each group) (mean age 40.4 years old) with slight female predominance. The most common clinical findings presented at diagnosis were low back pain followed by lower limb pain in the form of claudication and sciatica. L5-S1 disk prolapse was the most common level affected in both groups followed by L4-5 level. Regarding the clinical outcome, there was statistical significance in the VAS of low back pain at 9 months and 1-year follow-up favoring the fusion group with mean VAS 0.40 and 1.32 (p < 0.05). CONCLUSION: Clinical outcome was excellent in both groups. However, the reduction in low back pain after surgery was greater in the fusion group (p < 0.05). The rate of recurrent disk herniation at the surgical level in the nonfusion group was higher, but intraoperative blood loss, operation time, length of hospital stay, and total cost of procedure were all less in the patients undergoing discectomy alone. Although there is still controversy regarding the pros and cons of fusion in association with disk excision without instability, fusion results were highly favorable

Predictors of Long Covid 19 Syndrome

Background: Symptoms of covid persist in most cases with development of a multisystem syndrome called long covid syndrome.Objective: The aim of the work was to evaluate symptoms that persist after the acute stage of the disease in a cohort of patients with confirmed or suspected COVID 19 and to define the predictors for long COVID syndrome.Patients and method: This retrospective study involved 164 patients with previously confirmed or highly suspected COVID 19 and still attending to the post covid outpatient clinic in El-Minia University Chest Hospital complaining from persistence of symptoms or for regular follow up. Their data was obtained from their previous medical reports. Results: Post Covid 19 symptoms were found in about 86 % of the studied patients with 42.7% reported neuropsychiatric symptoms and 26.8% reported respiratory symptoms. The most common reported symptoms in nonsevere cases were the anxiety disorders (18.9%), followed by chronic fatigue and neuropathy (15.2%), while chronic dyspnea in 9.8% mostly in severe cases, while vertigo and headache in 9.1%, musculoskeletal symptoms in 6.1% and skin lesions in 3.7%.Conclusion: It could be concluded that persistence of symptoms is very common after acute Covid 19 infection. Chronic dyspnea was reported more frequently in severe cases while anxiety reported mostly by patients with mild disease

Fuzzy Logic-Based Improved Ventilation System For The Pharmaceutical Industry

Indoor air quality in pharmaceutical industry plays a vital role in the production and storing of medicine. Stable indoor environment including favorable temperature,humidity,air flow and number of microorganisms requires consistent monitoring.This paper aimed to develop a fuzzy logic-based intelligent ventilation system to control the indoor air quality in pharmaceutical sites.Specifically,in the proposed fuzzy inference system,the ventilation system can control the air flow and quality in accordance with the indoor temperature,humidity,air flow and microorganisms in the air.The MATLAB® fuzzy logic toolbox was used to simulate the performance of the fuzzy inference system.The results show that the efficiency of the system can be improved by manipulating the input-output parameters according to the user’s demands.Compared with conventional heating, ventilation and air-conditioning (HVAC) systems,the proposed ventilation system has the additional feature of the existence of microorganisms,which is a crucial criterion of indoor air quality in pharmaceutical laboratories

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Survey of CT radiation doses and iodinated contrast medium administration: an international multicentric study

ObjectiveTo assess the relationship between intravenous iodinated contrast media (ICM) administration usage and radiation doses for contrast-enhanced (CE) CT of head, chest, and abdomen-pelvis (AP) in international, multicenter settings. MethodsOur international (n = 16 countries), multicenter (n = 43 sites), and cross-sectional (ConRad) study had two parts. Part 1: Redcap survey with questions on information related to CT and ICM manufacturer/brand and respective protocols. Part 2: Information on 3,258 patients (18-96 years; M:F 1654:1604) who underwent CECT for a routine head (n = 456), chest (n = 528), AP (n = 599), head CT angiography (n = 539), pulmonary embolism (n = 599), and liver CT examinations (n = 537) at 43 sites across five continents. The following information was recorded: hospital name, patient age, gender, body mass index [BMI], clinical indications, scan parameters (number of scan phases, kV), IV-contrast information (concentration, volume, flow rate, and delay), and dose indices (CTDIvol and DLP). ResultsMost routine chest (58.4%) and AP (68.7%) CECT exams were performed with 2-4 scan phases with fixed scan delay (chest 71.4%; AP 79.8%, liver CECT 50.7%) following ICM administration. Most sites did not change kV across different patients and scan phases; most CECT protocols were performed at 120-140 kV (83%, 1979/2685). There were no significant differences between radiation doses for non-contrast (CTDIvol 24 [16-30] mGy; DLP 633 [414-702] mGycm) and post-contrast phases (22 [19-27] mGy; 648 [392-694] mGycm) (p = 0.142). Sites that used bolus tracking for chest and AP CECT had lower CTDIvol than sites with fixed scan delays (p < 0.001). There was no correlation between BMI and CTDIvol (r2 <= - 0.1 to 0.1, p = 0.931). ConclusionOur study demonstrates up to ten-fold variability in ICM injection protocols and radiation doses across different CT protocols. The study emphasizes the need for optimizing CT scanning and contrast protocols to reduce unnecessary contrast and radiation exposure to patients. Clinical relevance statementThe wide variability and lack of standardization of ICM media and radiation doses in CT protocols suggest the need for education and optimization of contrast usage and scan factors for optimizing image quality in CECT

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

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely