Concurrent Hand and Penile Gangrene following Prolonged Warfarin Use; a Case Report

Warfarin induced skin necrosis (WISN) is a rare but important side effect of warfarin. Early diagnosis may lessen the amount of permanent tissue damage and can prevent progression to full thickness skin necrosis. So, physicians should be aware of such a complication. Screening for protein C or S or anti-thrombin deficiencies, or presence of anti-phospholipid antibodies before beginning warfarin therapy, could be helpful to avoid high levels of international normalized ratio (INR). Here, we report a 54-year-old man who presented to the emergency department with acral and penile gangrene following prolonged use of warfarin.

Impact of silicon carbide device technologies on matrix converter design and performance

The development of high power density power converters has become an important topic in power electronics because of increasing demand in transportation applications including marine, aviation and vehicle system. The possibility for greater power densities due to absence of a DC link is made matrix converter topologies more attractive for these applications. Additionally, with the emerging SiC device technology, the operating switching frequency and temperature of the converter can be potentially increased. The extended switching frequency and temperature range provide opportunities to further improve the power density of the power converters. The aim of this thesis is to understand how SiC devices are different from the conventional Si devices and the effect these differences have on the design and performance of a matrix converter. Specific gate drive circuits are designed and implemented to fully utilize the high speed switching capabilities of these emerging semiconductor devices. A method to evaluate the conduction and switching losses and performance of Si and SiC power devices in the matrix converter circuit is developed. The developed method is used to compare power losses of matrix converters designed with different Si and SiC devices for a range of operating temperatures and switching frequencies. A design procedure for matrix converter input filters is proposed to fulfil power quality standard requirements and maximize the filter power density. The impact of the switching frequency on the input filter volume has also been considered in this work. The output waveform distortion due to commutation time in high switching frequency SiC matrix converters is also investigated and a three-step current commutation strategy is used to minimize the problem. Finally the influence of parasitic inductance on the behaviour of SiC power MOSFET matrix converters is investigated to highlight the challenges of high speed power devices

Experimental and analytical performance evaluation of SiC power devices in the matrix converter

With the commercial availability of SiC power devices, their acceptance is expected grows in consideration to the excellent low switching loss, high temperature operation and high voltage rating capabilities of these devices. This paper presents the comparative performance evaluation of different SiC power devices in matrix converter at various temperatures and switching frequencies. To this end, firstly, gate or base drive circuits for Normally-off SiC JFET, SiC MOSFET and SiC BJT which taking into account the special demands for these devices are presented. Then, three 2-phase to 1-phase matrix converters are built with different SiC power devices to measure the switching waveforms and power losses for them at different temperatures and switching frequencies. Based on the measured data, three different SiC power devices are compared in terms of switching times, conduction and switching losses and efficiency at different temperatures and switching frequencies. Furthermore, a theoretical investigation of the power losses of three phase matrix converter with Normally-off SiC JFET, SiC MOSFET, SiC BJT and Si IGBT is described. The power losses estimation indicates that a 7 KW matrix converter would potentially have an efficiency of approximately 96% in high switching frequency if equipped with SiC devices

Full and Modified Glasgow-Blatchford Bleeding Score in Predicting the Outcome of Patients with Acute Upper Gastrointestinal Bleeding; a Diagnostic Accuracy Study

Introduction: Screening of high risk patients and accelerating their treatment measures can reduce the burden of the disease caused by acute upper gastrointestinal (GI) bleeding. This study aimed to compare the full and modified Glasgow-Blatchford Bleeding Score (GBS and mGBS) in prediction of in-hospital outcomes of upper GI bleeding.Methods: In the present retrospective cross-sectional study, the accuracy of GBS and mGBS models were compared in predicting the outcome of patients over 18 years of age with acute upper GI bleeding confirmed via endoscopy, presenting to the emergency departments of 3 teaching hospitals during 4 years.Results: 330 cases with the mean age of 59.07 ± 19.00 years entered the study (63.60% male). Area under the curve of GBS and mGBS scoring systems were 0.691 and 0.703, respectively, in prediction of re-bleeding (p = 0.219), 0.562 and 0.563 regarding need for surgery (p = 0.978), 0.549 and 0.542 for endoscopic intervention (p = 0.505), and 0.767 and 0.770 regarding blood transfusion (p = 0.753). Area under the ROC curve of GBS scoring system regarding need for hospitalization in intensive care unit (0.589 vs. 0.563; p = 0.035) and mortality (0.597 vs. 0.564; p = 0.011) was better but the superiority was not clinically significant.Conclusion: GBS and mGBS scoring systems have similar accuracy in prediction of the probability of re-bleeding, need for blood transfusion, surgery and endoscopic intervention, hospitalization in intensive care unit, and mortality of patients with acute upper GI bleeding

Predisposing Factors of Seizure in Patients Presenting to the Emergency Department; a Brief Report

Introduction: Identifying predisposing factors of seizure can be somewhat helpful in preventing it from occurring. Objective: The present study has been designed aiming to assess the frequency of predisposing factors of seizure in patients visiting the emergency department (ED). Methods: The present prospective cross-sectional study was performed on adult patients presenting to ED following seizure during 1 year. Known or probable predisposing risk factors for seizure were extracted from various studies and were asked from patients or their relatives during history taking and clinical examination. Results: Finally, 246 seizure patients with the mean age of 38.8 ± 18.3 (18 – 92) years were included (68.7% male). Most patients were in the 18–29 years age group (41.1%), had an educational level less than high school diploma (59.8%), and were unemployed (47.8%). Among the predisposing factors of seizure, emotional stress with 107 (43.7%) cases, insomnia with 44 (17.9%), and irregular use of antiepileptic medications with 36 (14.6%) cases were the most common predisposing factors, respectively. In 43.5% of the patients, no identified predisposing factor was found. Insomnia (p = 0.002), stress (p < 0.001), and substance abuse (p < 0.001) were the most important predisposing factors of seizure in individuals less than 60 years old. In addition, being in the menstruation period was also shown to be a predisposing risk factor for women aged less than 60 years (p = 0.002). Conclusion: Emotional stress, insomnia, and irregular use of antiepileptic medication were the most important predisposing factors of seizure in the studied patients. In more than 40% of patients presenting to ED following seizure, no predisposing factor was found

Medical Journalism and Emergency Medicine

Nowadays, many researches in the field of medicine are conducting all around the world and medical journalism is a way to share the results. In fact, dissemination of the related manuscripts can prevent the repetitive research or may even lead to conducting a better survey. Therefore high quality medical journals are considered as up-to-date resources for further investigations. Medical journals are propagating their papers in various media including television programs, newspapers, internet websites and different social media. So they can influence the government policy makers, health-care professionals and even public. Moreover, most researchers hear about medical discoveries for the first time through medical journals and their related social media. So as well a high quality journal can help to improve medical science, a journal of poor quality can be damaging and distorting. Indeed, popular journals have the power of inventing a “communication storm” to draw attention to a certain topic. Thus they have to respect the accepted international principles to prevent spreading inaccurate and misleading data. This paper aims to review the previous and current situation of medical journalism by focus on field of emergency medicine

Demography of Medical Journals in Iran; a Cross-Sectional Study

Introduction: Policymaking in order to increase the quality of medical journals needs having accurate data from their current status. Objective: The present study was designed with the aim of introducing a demographic scheme of Iranian journals in the field of medical sciences. Method: This cross-sectional study was performed on all the medical journals being published in Iran in 2016. The list of all journal titles was extracted by referring to the medical journals databanks (ministry of health, Magiran, IranMedex, Irandoc and…), and the data required for the study were gathered using journals’ homepages or by phone or in person, by attending the journal’s office. Results: Totally, 521 journals were assessed. Publication language used was English in 297 (57%) journals and 515 (98.85%) were open access. 381 (73.1%) journals were published quarterly and the year of starting publication was 2010 onwards in case of 245 (48.0%) of journals. There were 29 (5.56%) journals, which were indexed in all 3 databases of ISI, PubMed and Scopus. Only 4.81% of the journals had an official impact factor announced by Thomson-Reuters or Clarivate Analytics Company. Mean time needed for review of articles was 1.89 ± 1.52 (0.5 – 12) months (n = 146) and mean time interval between accepting an article and its print or electronic publication was 3.63 ± 2.17 (0 – 12) months (n = 144). Rate of membership of these journals in COPE and ICMJE were 40% and 27%, respectively. Conclusion: Most medical journals being published in Iran were English quarterly journals that were regularly published in the fields of general medicine, open access, with university affiliations, centered in the capital, and more than 80% of them had started publishing from 2000 and afterwards

Predisposing Factors of Seizure in Patients Presenting to the Emergency Department; a Brief Report

Introduction: Identifying predisposing factors of seizure can be somewhat helpful in preventing it from occurring. Objective: The present study has been designed aiming to assess the frequency of predisposing factors of seizure in patients visiting the emergency department (ED). Methods: The present prospective cross-sectional study was performed on adult patients presenting to ED following seizure during 1 year. Known or probable predisposing risk factors for seizure were extracted from various studies and were asked from patients or their relatives during history taking and clinical examination. Results: Finally, 246 seizure patients with the mean age of 38.8 ± 18.3 (18 – 92) years were included (68.7% male). Most patients were in the 18–29 years age group (41.1%), had an educational level less than high school diploma (59.8%), and were unemployed (47.8%). Among the predisposing factors of seizure, emotional stress with 107 (43.7%) cases, insomnia with 44 (17.9%), and irregular use of antiepileptic medications with 36 (14.6%) cases were the most common predisposing factors, respectively. In 43.5% of the patients, no identified predisposing factor was found. Insomnia (p = 0.002), stress (p < 0.001), and substance abuse (p < 0.001) were the most important predisposing factors of seizure in individuals less than 60 years old. In addition, being in the menstruation period was also shown to be a predisposing risk factor for women aged less than 60 years (p = 0.002). Conclusion: Emotional stress, insomnia, and irregular use of antiepileptic medication were the most important predisposing factors of seizure in the studied patients. In more than 40% of patients presenting to ED following seizure, no predisposing factor was found

Demography of Medical Journals in Iran; a Cross-Sectional Study

Introduction: Policymaking in order to increase the quality of medical journals needs having accurate data from their current status. Objective: The present study was designed with the aim of introducing a demographic scheme of Iranian journals in the field of medical sciences. Method: This cross-sectional study was performed on all the medical journals being published in Iran in 2016. The list of all journal titles was extracted by referring to the medical journals databanks (ministry of health, Magiran, IranMedex, Irandoc and…), and the data required for the study were gathered using journals’ homepages or by phone or in person, by attending the journal’s office. Results: Totally, 521 journals were assessed. Publication language used was English in 297 (57%) journals and 515 (98.85%) were open access. 381 (73.1%) journals were published quarterly and the year of starting publication was 2010 onwards in case of 245 (48.0%) of journals. There were 29 (5.56%) journals, which were indexed in all 3 databases of ISI, PubMed and Scopus. Only 4.81% of the journals had an official impact factor announced by Thomson-Reuters or Clarivate Analytics Company. Mean time needed for review of articles was 1.89 ± 1.52 (0.5 – 12) months (n = 146) and mean time interval between accepting an article and its print or electronic publication was 3.63 ± 2.17 (0 – 12) months (n = 144). Rate of membership of these journals in COPE and ICMJE were 40% and 27%, respectively. Conclusion: Most medical journals being published in Iran were English quarterly journals that were regularly published in the fields of general medicine, open access, with university affiliations, centered in the capital, and more than 80% of them had started publishing from 2000 and afterwards