68 research outputs found

    Switch Matrix Logic Implementation of Electrical Impedance Tomography Measurement System

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    Electrical Impedance Tomography (EIT) is non-invasive technique that has the potential to be used in clinical environments for lung ventilation monitoring, cardiac and brain imaging applications. EIT has many advantages in terms of simplicity, cost and the absence of ionising radiations compared to the traditional imaging techniques such as magnetic resonance imaging (MRI) and X-rays. EIT systems usually consist of a ring of equally spaced electrodes placed around the part of the body of interest. A sinusoidal current source with a typical frequency of 50 kHz is used to inject current between an adjacent pair of electrodes. Then the imposed voltages on the remaining electrodes are measured sequentially. After that the current source is routed to the next pair and the cycle is repeated until one frame of data is collected. For eight electrodes 8x5 measurements per frame are collected. Mathematical algorithms are used to construct an image of the impedance distribution inside the closed volume. In order to apply the current source and measure the imposed voltages on the electrodes a switch matrix is needed. In this work, a circuit implementation of the switch matrix for eight electrodes is presented. The system consists of logic blocks used to generate eight logic signals (CL1-CL8) needed to route the differential current source to the appropriate electrode pair. For example, when the logic signals CL1 and CL2 are both high, the differential current is routed to electrode pair 1 and 2. During this time other blocks are used to generate 8 logic signals (VL1-VL8) required to measure the imposed voltages on the remaining electrodes in the following sequence, V3-V4, V4-V5, V5-V6, V6-V7 and V7-V8. The logic blocks used in the implementation consists of mono-stable elements in addition to standard logic gates. Simulation results indicate that the implementation of the designed circuit is feasible in both hardware and software form. Keywords: Electrical Impedance Tomography, Switch Matrix Logic, Simulated Measurement Systems

    High Efficiency Power Management Unit for Implantable Optical-Electrical Stimulators

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    Battery-less active implantable devices are of interest because they offer longer life span and eliminate costly battery replacement surgical interventions. This is possible as a result of advances in inductive power transfer and development of power management circuits to maximize the overall power transfer and provide various voltage levels for multi-functional implantable devices. Rehabilitation therapy using optical stimulation of genetically modified peripheral neurons requires high current loads. Standard rectification topologies are inefficient and have associated voltage drops unsuited for miniaturized implants. This paper presents an integrated power management unit (PMU) for an optical-electrical stimulator to be used in the treatment of motor neurone disease. It includes a power-efficient regulating rectifier with a novel body biased high-speed comparator providing 3.3 V for the operation of the stimulator, a 3-stage latch-up charge pump with 12 V output for the input stage of the optical-electrical stimulator, and 1.8 V for digital control logic. The chip was fabricated in a 0.18 μm CMOS process. Measured results show that for a regulated output of 3.3 V delivering 30.3 mW power, the peak power conversion efficiency is 84.2% at 6.78 MHz inductive link tunable frequency reducing to 70.3% at 13.56 MHz. The charge pump with on chip capacitors has 90.9% measured voltage conversion efficiency

    Development of a biosensor for fast point-of-care blood analysis of Troponin

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    We present the development of novel tetrapolar EIS biosensor for the detect of troponin. Troponin has considerable diagnostic power and provide invaluable prognostic information for risk stratification. of acute coronary syndromes. Clinical Relevance— A feasibility study was undertaken to assess the diagnostic performance of serial cardiac troponin measurements which is excellent as these structural proteins are unique to the heart and thus sensitive and specific of damage to the myocardium. clinical molecular diagnostics and home healthcare. Troponin’s biosensors would provide point-of-care and rapid decision making for the early detection of CS. Clinically relevant window of cTnI testing, concentrations from 10pM to 0.1μM were achieved

    Potassium Ion Channels in Glioma: From Basic Knowledge into Therapeutic Applications

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    Ion channels, specifically those controlling the flux of potassium across cell membranes, have recently been shown to exhibit an important role in the pathophysiology of glioma, the most common primary central nervous system tumor with a poor prognosis. Potassium channels are grouped into four subfamilies differing by their domain structure, gating mechanisms, and functions. Pertinent literature indicates the vital functions of potassium channels in many aspects of glioma carcinogenesis, including proliferation, migration, and apoptosis. The dysfunction of potassium channels can result in pro-proliferative signals that are highly related to calcium signaling as well. Moreover, this dysfunction can feed into migration and metastasis, most likely by increasing the osmotic pressure of cells allowing the cells to initiate the “escape” and “invasion” of capillaries. Reducing the expression or channel blockage has shown efficacy in reducing the proliferation and infiltration of glioma cells as well as inducing apoptosis, priming several approaches to target potassium channels in gliomas pharmacologically. This review summarizes the current knowledge on potassium channels, their contribution to oncogenic transformations in glioma, and the existing perspectives on utilizing them as potential targets for therapy.The APC was funded by the Lebanese International University

    Knowledge, attitude and practice of Lebanese community pharmacists with regard to self-management of low back pain

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    Purpose: To determine the knowledge, attitude and reported practice of Lebanese community pharmacists who advise persons who present with low back pain.Methods: This was a multi-center cross-sectional study conducted in over 300 community pharmacies across Lebanon from December 2017 to May 2018. Pharmacists working at a community pharmacy were considered eligible, and those who volunteered to participate completed the questionnaire. The questionnaire was designed for self-completion by the pharmacist and included demographic questions about the respondent, questions that assessed knowledge and attitude toward low back pain, and questions about treatment to reflect and characterize the nature of practice. The primary outcome was to determine the knowledge, attitude and reported practice of the Lebanese pharmacists advising people who presented with low back pain. The secondary outcome was to assess factors that affect knowledge, attitude, and practice.Results: The response of 320 community pharmacists was analysed. The proportion of pharmacists with good knowledge about low back pain (51. 7 %) was slightly higher than those with poor knowledge (48. 3 %). Oral therapy was the most prescribed dosage form for back pain compared to local patch and cream. Among oral dosage forms, non-steroidal anti-inflammatory drugs were the most prescribed medications (42 %). Of the patients’ referral to the physician if necessary, 73.1 % of the referrals were by pharmacists.Conclusion: Community pharmacists in Lebanon demonstrate an acceptable level of knowledge of back pain, yet major gaps still exist, particularly in terms of the quality of advice. Hence, more education is needed to provide better quality of advice. Keywords: Attitude, Knowledge, Low back pain, Reported practice, Quality of advic

    Exploring the effects of health behaviors and mental health on students' academic achievement: a cross-sectional study on lebanese university students

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    Background High academic achievement, an important determinant of future success, is known to be influenced by many factors including dietary behavior, lifestyle and mental health, among others. The objectives of the current study were to explore university students’ nutritive habits, daily lifestyle, and mental status, and to scrutinize the associations between these factors and students’ academic achievement. Methods A cross-sectional study was conducted among students of a private Lebanese university, using an electronic survey. Diet, eating habits, physical activity, sleep, and smoking were evaluated, and mental health was assessed using a validated Arabic version of the combined Depression, Anxiety, Stress Score (DASS-8). Academic achievement was measured using the Subjective Academic Achievement Scale (SAAS). Results A total of 1677 students participated in the questionnaire. The results of a linear regression taking the SAAS score as the dependent variable, showed that students who have a non-scientific versus scientific major (Beta = 0.53), and having breakfast ≥ 4 days per week compared to less than 2 days (Beta = 0.28) were significantly associated with higher SAAS scores. More psychological distress (Beta = − 0.06) and a higher number of days of eating out (Beta = − 0.07) were significantly associated with lower SAAS scores. Conclusions This is the first investigation on a Lebanese university students’ academic success in relation to lifestyle and mental profiles. Better academic achievement was demonstrated by students having healthier dietary and lifestyle habits, as well as less distressing mental status. Such results, in light of the compounded and unprecedented crises with which Lebanon has been assailed, suggest the need to focus on promoting healthy habits among students in higher education as a possible driver of better academic success.None.Scopu

    Factors Affecting Influenza Vaccination Uptake and Attitudes among Lebanese University Students: The Impact of Vaccination Promotional Programs and COVID-19 Pandemic

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    Vaccination is the most effective preventative strategy against influenza, yet university students' influenza vaccination uptake remains low. This study aimed firstly to determine the percentage of university students who were vaccinated for the 2015-2016 influenza season and to identify reasons for non-vaccination, and secondly to examine the impact of external factors (on-campus/online influenza awareness campaigns and COVID-19 pandemic) on their influenza vaccination uptake and attitudes for the 2017-2018 and 2021-2022 influenza seasons. A descriptive study was conducted over three phases for three influenza seasons at a Lebanese university in the Bekaa Region. Based on data collected in 2015-2016, promotional activities were developed and implemented for the other influenza seasons. This study was conducted using an anonymous, self-administered questionnaire by students. The majority of the respondents in the three studies did not receive the influenza vaccine (89.2% in the 2015-2016 study, 87.3% in the 2017-2018 study, and 84.7% in the 2021-2022 study). Among the unvaccinated respondents, the main reason for non-vaccination was that they thought that they did not need it. The primary reason for vaccination among those who were vaccinated was that they believed they were at risk of catching influenza in a 2017-2018 study and due to the COVID-19 pandemic in the 2021-2022 study. As for attitudes towards influenza vaccination post-COVID-19, significant differences were shown among the vaccinated and unvaccinated respondents. The vaccination rates among university students remained low despite of the awareness campaigns and COVID-19 pandemic.The APC was funded by the Lebanese International University.Scopu

    Knowledge and awareness of stroke and associated factors in the Saudi general population: a cross-sectional study

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    IntroductionStroke is a major cause of death and disability globally and in Saudi Arabia as well. Prevention and management of stroke depend highly on raising knowledge and awareness about the disease.PurposeThe purpose of this study was to evaluate Saudi adult's knowledge and awareness about stroke and determine the associated factors.Materials and methodsA cross-sectional online survey was conducted in May–July 2022 among Saudi citizens. Assessments of stroke knowledge about risk factors, symptoms, and response to stroke symptoms were evaluated. Logistic regression was conducted to assess the association between the socio-demographic characteristics and knowledge.ResultsA total of 389 participants were enrolled with the majority (81.7%) being male participants. Less than half of the study subjects (43.3%) identified four out of five correct answers related to general knowledge about stroke. Almost all the participants were able to identify at least one risk factor associated with stroke. The majority of the participants (81.2%) believed that physical inactivity was the most common risk factor associated with stroke. Approximately three-quarters of participants considered difficulty speaking and understanding speech, followed by the sudden loss of consciousness as the most common stroke manifestation. Participants with a history of hypertension, dyslipidemia, and obesity had significantly higher odds of identifying at least one early stroke symptom (OR 2.271 [95% CI 1.402 3.677], 2.059 [95% CI 1.273 3.328], and 2.665 [95% CI 1.431 4.963], respectively).ConclusionOur study revealed that participants have good knowledge about stroke. Nonetheless, further efforts are required to raise awareness and educate the public to optimize and ensure better treatment outcomes

    The impact of COVID-19 on the mental health of Lebanese pharmacists: A national cross-sectional study

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    IntroductionThe COVID-19 pandemic has induced a global mental health crisis with variable consequences. This study aimed to assess the psychological impact of COVID-19 regarding anxiety, insomnia, depression, and response to trauma on pharmacists in Lebanon during COVID-19, and to identify factors contributing to psychological distress.MethodsThis was a cross-sectional study among pharmacists that involved the use of the 7-item Generalized Anxiety Disorder (GAD-7), 7-item Insomnia Severity Index (ISI), Patient Health Questionnaire 9-item depression module (PHQ-9), and Impact of Event Scale revised (IES-R) subscales. Descriptive statistical analyses were performed to determine the study distribution. The associations between the scores and the participants’ characteristics were assessed using the Chi-square test. Four binary logistic regression models were used to evaluate the association between the scores and the potential confounders, followed by four multivariable logistic regressions. An alpha of 0.05 was used to determine statistical significance.ResultsParticipants comprised 311 pharmacists from all Lebanese districts, of whom 251 (80.7%) were females and 181 (58.2%) aged between 26 and 35 years. The majority of the participants were community pharmacists (n = 178, 57.2%). A considerable proportion of participants had symptoms of anxiety (n = 128, 41.2%), insomnia (n = 64, 20.6%), depression (n = 157, 50.5%), and subjective stress (n = 227, 78.8%). Higher anxiety (aOR: 1.73, 95% CI: 1.08; 2.78, p-value: 0.02), higher depression (aOR: 3.06, 95% CI: 1.73; 5.39, p-value: 0.001), and higher stress (aOR: 1.86, 95 percent CI: 1.11; 3.14, p-value: 0.02) scores were significantly associated with pharmacists who reported that their work involves contact with infected/suspected COVID-19 patients. Interestingly, pharmacists who expressed concern about contracting COVID-19 infection had significantly higher anxiety (aOR: 2.35, 95% CI: 1.40; 3.94, p-value: 0.001) and higher depression scores (aOR: 2.64, 95% CI: 1.49; 4.67, p-value: 0.001) respectively.ConclusionThe preliminary results from pharmacists in Lebanon reflect increase in stress, burden, and frustration felt by pharmacists, creating a negative impact on their mental health and well-being during the global pandemic. As frontline healthcare workers, the role of pharmacists in the community should not be overlooked, and their mental health should be well investigated
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