A proposed optimized equivalent circuit and performance analysis of dielectric barrier discharge ozone generator

Traditionally, low-frequency power supplies are used in dielectric barrier discharge (DBD) ozone generators. These generators require a very high output voltage. This may limit ozone production due to limitations imposed by the dielectric strength of the insulating material. Low-frequency generators also present low efficiency, large volumes, and difficulty in controlling ozone production. On the other hand, the advantages of high frequency DBD ozone generators are the increased power density applied to the chamber electrodes, and the voltage applied to the ozone chamber decreases, allowing for higher ozone production efficiency. From this point of view, in order to enhance and control the DBD ozone generator operating at high frequency, it is necessary to determine all parameter values and optimize the equivalent model for this type of generator. This work presents and proposes the practical methodologies used to extract all parameters of the high voltage high frequency (HVHF) transformer which can be used in these systems. Resonant frequency control techniques are presented in this paper. Elimination of the stray capacitance effect will also be implemented in this paper

Genetics of Allergic Asthma and Current Perspectives on Therapeutic Management

Globally, more than 300 million people are asthmatics and this number has been estimated to become 400 million by 2025. Asthma is a chronic inflammatory condition, which, although has no cure, is treatable in most patients. The most common structural alterations in asthmatic airways include thickening of the epithelial and sub epithelial layers, increased airway smooth muscle mass, and angiogenesis. Several genetically controlled factors greatly influence the predisposition and severity of allergic asthma. Twin studies have attributed as much as 75% of asthma susceptibility to heredity. Particularly, genome-wide association studies (GWASs) have discovered several asthma and/or atopy susceptibility genes. Current treatment protocols for managing asthma involve the use of corticosteroids and β-agonists. Over the last 40 years, there has been a marked development-targeted therapy for asthma, such as anti-leukotrienes, anti-immunoglobulin (Ig)E, anti-tumor necrosis factor (TNF)-α, and anti-interleukins (ILs) (Th2 cytokines). To identify novel targets and to develop newer drug generations, better understanding of asthma molecular pathophysiology is required. Furthermore, the pharmacogenetic studies, focusing on better understanding of beneficial or/and adverse effects to anti-asthma drugs, will also facilitate the development of more effective and targeted treatments in specific subpopulations of patients suffering from asthma

New methodology to detect the effects of emotions on different biometrics in real time

Recently, some problems have appeared among medical workers during the diagnosis of some diseases due to human errors or the lack of sufficient information for the diagnosis. In medical diagnosis, doctors always resort to separating human emotions and their impact on vital parameters. In this paper, a methodology is presented to measure vital parameters more accurately while studying the effect of different human emotions on vital signs. Two designs were implemented based on the microcontroller and National Instruments (NI) myRIO. Measurements of four different vital parameters are measured and recorded in real time. At the same time, the effects of different emotions on those vital parameters are recorded and stored for use in analysis and early diagnosis. The results proved that the proposed methodology can contribute to the prediction and diagnosis of the initial symptoms of some diseases such as the seventh nerve and Parkinson’s disease. The two proposed designs are compared with the reference device (beurer) results. The design using NI myRIO achieved more accurate results and a response time of 1.4 seconds for real-time measurements compared to its counterpart based on microcontrollers, which qualifies it to work in intensive care units

QoS Categories Activeness-Aware Adaptive EDCA Algorithm for Dense IoT Networks

IEEE 802.11 networks have a great role to play in supporting and deploying of the Internet of Things (IoT). The realization of IoT depends on the ability of the network to handle a massive number of stations and transmissions, and to support Quality of Service (QoS). IEEE 802.11 networks enable the QoS by applying the Enhanced Distributed Channel Access (EDCA) with static parameters regardless of existing network capacity or which Access Category (AC) of QoS is already active. Our objective in this paper is to improve the efficiency of the uplink access in 802.11 networks; therefore we proposed an algorithm called QoS Categories Activeness-Aware Adaptive EDCA Algorithm (QCAAAE) which adapts Contention Window (CW) size, and Arbitration Inter-Frame Space Number (AIFSN) values depending on the number of associated Stations (STAs) and considering the presence of each AC. For different traffic scenarios, the simulation results confirm the outperformance of the proposed algorithm in terms of throughput (increased on average 23%) and retransmission attempts rate (decreased on average 47%) considering acceptable delay for sensitive delay services.Comment: 17 pages, 10 figure

New Method to Implement and Analysis of Medical System in Real Time

The use of information technology and technological medical devices has contributed significantly to the transformation of healthcare. Despite that, many problems have arisen in diagnosing or predicting diseases, either as a result of human errors or lack of accuracy of measurements. Therefore, this paper aims to provide an integrated health monitoring system to measure vital parameters and diagnose or predict disease. Through this work, the percentage of various gases in the blood through breathing is determined, vital parameters are measured and their effect on feelings is analyzed. A supervised learning model is configured to predict and diagnose based on biometric measurements. All results were compared with the results of the Omron device as a reference device. The results proved that the proposed design overcame many problems as it contributed to expanding the database of vital parameters and providing analysis on the effect of emotions on vital indicators. The accuracy of the measurements also reached 98.8% and the accuracy of diagnosing COVID-19 was 64%. The work also presents a user interface model for clinicians as well as for smartphones using the Internet of things

The diagnostic accuracy of intraoperative frozen section biopsy for diagnosis of sentinel lymph node metastasis in breast cancer patients: a meta-analysis

: Sentinel lymph node (SLN) sampling is important for evaluating the nodal stage of breast cancer when the axillary nodes are clinically free of metastasis. The intraoperative frozen section (IFS) of SLN is used for lymph node assessment. This meta-analysis aims to provide evidence about the diagnostic accuracy and the applicability of IFS of SLN in breast cancer patients. Data were collected by searching PubMed, Cochrane, Scopus, and Web of Science electronic databases for trials matching our eligibility criteria. The statistical analysis included the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and pooled studies' diagnostic odds ratio outcomes. The analyses were conducted using the Open Meta-analyst software. This meta-analysis pooled the results of 110 studies. The overall sensitivity of IFS for SLN metastasis was 74.7%; 95% CI [72.0, 77.2], P < 0.001. It was 31.4% 95% CI [25.2, 38.3], P < 0.001 for the micro-metastasis, and 90.2%; 95% CI [86.5, 93.0], P < 0.001 for the macro-metastasis. The overall specificity was 99.4%; 95% CI [99.2, 99.6], P < 0.001. The overall positive likelihood ratio was 121.4; 95% CI [87.9, 167.6], P < 0.001, and the overall negative likelihood ratio was 0.226; 95% CI [0.186, 0.274], P < 0.001. The overall diagnostic odds ratio of IFS for diagnosing SLN metastasis was 569.5; 95% CI [404.2, 802.4], P < 0.001. The intraoperative frozen section of SLN has good sensitivity for diagnosing breast cancer macro-metastasis. However, the sensitivity is low for micro-metastasis. The specificity is very satisfactory

Prevalence of Post COVID-19 Condition among Healthcare Workers: Self-Reported Online Survey in Four African Countries, December 2021–January 2022

The impact of Post COVID-19 Condition (PCC) is ongoing despite the declaration that the 2019 COVID-19 pandemic has ended. In this study, we explore the prevalence of PCC among healthcare workers (HCWs) in four African Countries and its influence on their professional performance. This study was conducted as an online cross-sectional survey of healthcare workers from four African countries (Cameroon, Egypt, Nigeria, and Somalia) between the 20th of December 2021 to 12th of January 2022. We determined the prevalence of PCC based on the WHO case definition and assessed variables associated with a higher prevalence of PCC in these countries using univariable and multivariable logistic regression analyses. A total of 706 HCWs from four African countries were included in this survey. Most of the HCWs were aged between 18–34 years (75.8%, n = 535). Our findings showed that 19.5% (n = 138) of the HCWs had tested positive for SARS-CoV-2. However, 8.4% (n = 59) were symptomatic for COVID-19 but tested negative or were never tested. Two-thirds of the HCWs (66.4%, n = 469) have received a COVID-19 vaccine and 80.6% (n = 378) of those vaccinated had been fully vaccinated. The self-reported awareness rate of PCC among the HCWs was 16.1% (n = 114/706) whereas the awareness rate of PCC among COVID-19-positive HCWs was 55.3% (n = 109/197). The prevalence of PCC among HCWs was 58.8% (n = 116). These changes include the self-reported symptoms of PCC which included headache (58.4%, n = 115), fatigue (58.8%, n = 116), and muscle pain (39.6%, n = 78). Similarly, 30% (n = 59) and 20.8% (n = 41) of the HCWs reported the loss of smell and loss of taste long after their COVID-19 infection, respectively. Some HCWs (42%, n = 83) believed that their work performance has been affected by their ongoing symptoms of PCC. There was no significant difference in the prevalence of PCC among the vaccinated and unvaccinated HCWs (p > 0.05). Of the socio-demographic variables, age (older HCWs between 45–54 years; OR:1.7; 95% CI: 1.06, 10.59; p = 0.001) and location (Egypt; OR:14.57; 95% CI: 2.62, 26.76; p = 0.001) were more likely to have experienced PCC than other age groups and countries respectively. The study revealed a low prevalence of PCC among the surveyed HCWs. In addition, it observed the need for adequate medical and psychological support to HCWs with PCC and improved mass advocacy campaigns on PCC

Characteristics of mentally ill offenders from 100 psychiatric court reports

<p>Abstract</p> <p>Background</p> <p>There is an increasing probability that the psychiatrist will, willingly or not, come into contact with mentally ill offenders in the course of their practice. There are increasing rates of violence, substance abuse and other psychiatric disorders that are of legal importance. Therefore, the aim of this work was to investigate the rates of different mental disorders in 100 court reports and to investigate the characteristics of mentally ill offenders.</p> <p>Methods</p> <p>All cases referred from different departments of the legal system to the forensic committee for assessment of legal accountability over 13-months duration were included. A specially designed form was prepared for data collection. Cases were classified into five groups: murder, robbery, financial offences, violent and simple offences and a group for other offences. Data were subjected to statistical analysis and comparisons between different groups of subjects were performed by analysis of variance (ANOVA).</p> <p>Results</p> <p>Men constituted 93% of cases. In all, 73% of offenders were younger than 40 years old. Schizophrenia cases made up 13% of the total, substance related cases constituted 56% and amphetamine cases alone made up 21%; 10% of cases were antisocial personality disorders, and 51% of cases were classified as having a low education level. Unemployment was found in 34% of cases. The final decision of the forensic committee was full responsibility in 46% of cases and partial responsibility in 11% of cases, with 33% considered non-responsible. A total of 58% of cases had had contact with psychiatric healthcare prior to the offence and in 9% of cases contact had been in the previous 12 weeks. A history of similar offences was found in 32% of cases. In all, 14% of the offences were murders, 8% were sexual crimes, and 31% were violent/simple crimes.</p> <p>Conclusions</p> <p>The ability of the legal system to detect cases was good, while the ability of the healthcare system to predict crimes and offences was weak, as 58% of cases had had previous contact with the healthcare system previously. Substance abuse, especially amphetamine abuse, played an important role.</p

Exercise-induced bronchoconstriction and atopy in Tunisian athletes

<p>Abstract</p> <p>Background</p> <p>This study is a cross sectional analysis, aiming to evaluate if atopy is as a risk factor for exercise induced bronchoconstriction (EIB) among Tunisian athletes.</p> <p>Methods</p> <p>Atopy was defined by a skin prick test result and EIB was defined as a decrease of at least 15% in forced expiratory volume in one second (FEV1) after 8-min running at 80–85% HRmaxTheo. The study population was composed of 326 athletes (age: 20.8 ± 2.7 yrs – mean ± SD; 138 women and 188 men) of whom 107 were elite athletes.</p> <p>Results</p> <p>Atopy was found in 26.9% (88/326) of the athletes. Post exercise spirometry revealed the presence of EIB in 9.8% of the athletes including 13% of the elite athletes. Frequency of atopy in athletes with EIB was significantly higher than in athletes without EIB [62.5% vs 23.1%, respectively].</p> <p>Conclusion</p> <p>This study showed that atopic Tunisian athletes presented a higher risk of developing exercise induced bronchoconstriction than non-atopic athletes.</p

Utilisation of an operative difficulty grading scale for laparoscopic cholecystectomy

Background A reliable system for grading operative difficulty of laparoscopic cholecystectomy would standardise description of findings and reporting of outcomes. The aim of this study was to validate a difficulty grading system (Nassar scale), testing its applicability and consistency in two large prospective datasets. Methods Patient and disease-related variables and 30-day outcomes were identified in two prospective cholecystectomy databases: the multi-centre prospective cohort of 8820 patients from the recent CholeS Study and the single-surgeon series containing 4089 patients. Operative data and patient outcomes were correlated with Nassar operative difficultly scale, using Kendall’s tau for dichotomous variables, or Jonckheere–Terpstra tests for continuous variables. A ROC curve analysis was performed, to quantify the predictive accuracy of the scale for each outcome, with continuous outcomes dichotomised, prior to analysis. Results A higher operative difficulty grade was consistently associated with worse outcomes for the patients in both the reference and CholeS cohorts. The median length of stay increased from 0 to 4 days, and the 30-day complication rate from 7.6 to 24.4% as the difficulty grade increased from 1 to 4/5 (both p < 0.001). In the CholeS cohort, a higher difficulty grade was found to be most strongly associated with conversion to open and 30-day mortality (AUROC = 0.903, 0.822, respectively). On multivariable analysis, the Nassar operative difficultly scale was found to be a significant independent predictor of operative duration, conversion to open surgery, 30-day complications and 30-day reintervention (all p < 0.001). Conclusion We have shown that an operative difficulty scale can standardise the description of operative findings by multiple grades of surgeons to facilitate audit, training assessment and research. It provides a tool for reporting operative findings, disease severity and technical difficulty and can be utilised in future research to reliably compare outcomes according to case mix and intra-operative difficulty