Value of ABCD2-F in predicting cerebral ischemic attacks: Three months follow-up after the primary attack

Cerebrovascular attack (CVA) and transient ischemic attack (TIA) are major causes of emergency department visits around the globe. A significant number of these patients may experience repeat attacks if left untreated. Several risk stratifying scoring systems have been developed in recent years to point out the high risk patients. ABCD2 is based on age, blood pressure, clinical status, diabetes mellitus, and duration of symptoms and is used commonly for this purpose. In this study, we were to enhance its sensitivity and specificity with the addition of another criterion namely atrial fibrillation and making ABCD2-F. A prospective study in two hospitals was performed and 138 patients diagnosed with TIA/CVA were enrolled. Demographic, clinical, and paraclinical data of all patients were registered. All patients were followed for three months for any sign or symptom of a recurrent ischemic attack. Recurrent ischemic attacks happened in 9.4 of the patients. None of the criteria of ABCD2-F was associated with higher chance of ischemic attacks. Similarly, ABCD2-F was not different between patients with or without repeat cerebral ischemia. The addition of atrial fibrillation to ABCD2 did not enhance the accuracy of this scoring system to detect patients high risk for repeat cerebral ischemia. More studies in the future to improve sensitivity and specificity of this test are warranted. © 2016 Tehran University of Medical Sciences. All rights reserved

Device-spectroscopy of magnetic field effects in a polyfluorene organic light-emitting diode

We perform charge-induced absorption and electroluminescence spectroscopy in a polyfluorene organic magnetoresistive device. Our experiments allow us to measure the singlet exciton, triplet exciton and polaron densities in a live device under an applied magnetic field, and to distinguish between three different models that were proposed to explain organic magnetoresistance. These models are based on different spin-dependent interactions, namely exciton formation, triplet exciton-polaron quenching and bipolaron formation. We show that the singlet exciton, triplet exciton and polaron densities and conductivity all increase with increasing magnetic field. Our data are inconsistent with the exciton formation and triplet-exciton polaron quenching models.Comment: 4 pages, two figure

Modeling and numerical study of primary breakup under diesel conditions

A recently introduced stochastic model for reduced numerical simulation of primary jet breakup is evaluated by comparing model predictions to DNS results for primary jet breakup under diesel conditions. The model uses one-dimensional turbulence (ODT) to simulate liquid and gas time advancement along a lateral line of sight. This one-dimensional domain is interpreted as a Lagrangian object that is advected downstream at the jet bulk velocity, thus producing a flow state expressed as a function of streamwise and lateral location. Multiple realizations are run to gather ensemble statistics that are compared to DNS results. The model incorporates several empirical extensions of the original ODT model that represent the phenomenology governing the Weber number dependence of global jet structure. The model as previously formulated, including the assigned values of tunable parameters, is used here without modification in order to test its capability to predict various statistics of droplets generated by primary breakup. This test is enabled by the availability of DNS results that are suitable for model validation. Properties that are examined are the rate of bulk liquid mass conversion into droplets, the droplet size distribution, and the dependence of droplet velocities on droplet diameter. Quantities of greatest importance for engine modeling are found to be predicted with useful accuracy, thereby demonstrating a more detailed predictive capability by a highly reduced numerical model of primary jet breakup than has previously been achieved

Profiles of risk: a qualitative study of injecting drug users in Tehran, Iran

BACKGROUND: In Iran, there are an estimated 200,000 injecting drug users (IDUs). Injecting drug use is a relatively new phenomenon for this country, where opium smoking was the predominant form of drug use for hundreds of years. As in many countries experiencing a rise in injecting drug use, HIV/AIDS in Iran is associated with the injection of drugs, accounting for transmission of more than two-thirds of HIV infections. This study aimed to: describe the range of characteristics of IDUs in Tehran, Iran's capital city; 2) examine the injecting-related HIV risk behaviors of IDUs, and 3) suggest necessary interventions to prevent HIV transmission among IDUs and their families and sex partners. METHODS: Using rapid assessment and response methods with a qualitative focus, six districts of Tehran were selected for study. A total of 81 key informants from different sectors and 154 IDUs were selected by purposeful, opportunistic and snowball sampling, then interviewed. Ethnographic observations were done for mapping and studying injecting-related HIV risk settings and behaviors. Modified content analysis methods were used to analyze the data and extract typologies of injecting drug users in Tehran. RESULTS: Evidence of injecting drug use and drug-related harm was found in 5 of 6 study districts. Several profiles of IDUs were identified: depending on their socioeconomic status and degree of stability, IDUs employed different injecting behaviors and syringe hygiene practices. The prevalence of sharing injection instruments ranged from 30–100%. Varied magnitudes of risk were evident among the identified IDU typologies in terms of syringe disinfection methods, level of HIV awareness, and personal hygiene exhibited. At the time of research, there were no active HIV prevention programs in existence in Tehran. CONCLUSION: The recent rise of heroin injection in Iran is strongly associated with HIV risk. Sharing injection instruments is a common and complex behavior among Iranian IDUs. For each profile of IDU we identified, diverse and targeted interventions for decreasing sharing behavior and/or its harms are suggested. Some notable efforts to reduce the harm of injecting drug use in Iran have recently been accomplished, but further policies and action-oriented research for identification of effective preventive interventions are urgently needed

Temperature dependence of the charge carrier mobility in gated quasi-one-dimensional systems

The many-body Monte Carlo method is used to evaluate the frequency dependent conductivity and the average mobility of a system of hopping charges, electronic or ionic on a one-dimensional chain or channel of finite length. Two cases are considered: the chain is connected to electrodes and in the other case the chain is confined giving zero dc conduction. The concentration of charge is varied using a gate electrode. At low temperatures and with the presence of an injection barrier, the mobility is an oscillatory function of density. This is due to the phenomenon of charge density pinning. Mobility changes occur due to the co-operative pinning and unpinning of the distribution. At high temperatures, we find that the electron-electron interaction reduces the mobility monotonically with density, but perhaps not as much as one might intuitively expect because the path summation favour the in-phase contributions to the mobility, i.e. the sequential paths in which the carriers have to wait for the one in front to exit and so on. The carrier interactions produce a frequency dependent mobility which is of the same order as the change in the dc mobility with density, i.e. it is a comparably weak effect. However, when combined with an injection barrier or intrinsic disorder, the interactions reduce the free volume and amplify disorder by making it non-local and this can explain the too early onset of frequency dependence in the conductivity of some high mobility quasi-one-dimensional organic materials.Comment: 9 pages, 8 figures, to be published in Physical Review

Incidence of self-reported interpersonal violence related physical injury in Iran

Background: Violence is the cause of death for 1.5 million people in a year. Objectives: Our study aimed to estimate the incidence rate of self-reported interpersonal violence related physical injury (VRPI) and its associated factors in Iran. Patients and Methods: The sample included people ranged from 15 to 64 years old who were residing in Iran. A total of 1525 clusters were selected from the whole country. Six families were selected from each cluster via a systematic random sampling method. Then, the residential units were identified and the interviewers contacted the inhabitants. In the next step, one of the family members was selected by using Kish grid method. The instrument was a researcher-made questionnaire and consisted of two sections; demographics and project related data. Face validity and content validity of our questionnaire were investigated based on expert opinions and the reliability was confirmed by a pilot study, as well. The inclusion criteria were considered for choosing the interviewers. An interviewer was assigned for each 42 participants (7 clusters). An educational seminar was held for the administrative managers (54 persons) and interviewers (230 persons) for a week. The field work was distributed among all 46 Medical Sciences universities in Iran. In each university, administrative issues were related to an executive director. Mann-Whitney U test and odds ratio were used to analyze the data with 95 confidence interval. α value was considered less than 5. Results: The frequency of VRPI among 7886 participants was 24 during the last three months. The incidence rate of interpersonal VRPI was estimated at 3.04 per 1000 population (95 CI: 2.66-3.42) during a three-month interval in Iran. The incidence was 4.72 per 1000 population (95 CI: 4.01-5.43) for males and 1.78 per 1000 population (95 CI: 1.39-2.17) for females during a three-month interval. The mean (SD) of age of the participants with and without a history of VRPI were 26.5 (7.21) and 33.05 (12.05) years, respectively (P = 0.008). Considering the participants� gender, 66.7 were males (OR = 2.66, 95 CI: 1.14-6.23). Khuzestan Province had the most VRPIs (25 of all VRPIs). Streets and roads were the places with the highest frequency of injury (50). The most frequent injured organ was the upper limb (54.17). The most prevalent type of injury was a superficial wound (50). Finally, the most common place of treatment was home (45.83). Conclusions: We determined the incidence rate of self-reported interpersonal VRPI for the first time in Iran based on a national survey. The injuries were more common among young men. We suggest consecutive national surveys with different data gathering methods and more sample sizes. © 2015, Iranian Red Crescent Medical Journal

Principles of primary survey and resuscitation in cases of pediatric trauma

Trauma is a common cause of death and disability in children. Proper approach to pediatric trauma involves adherence to ABCDE sequence in the primary survey and resuscitation in order to promptly recognize and manage life-threatening conditions immediately. This readily reviewed sequence includes A: establishment and maintenance of a patent airway while maintaining cervical spine immobilization; B: evaluation of breathing, ventilation and oxygenation, immediate treatment of tension pneumothorax, open pneumothorax and massive hemothorax; C: evaluation and treatment of circulatory compromise and shock; D: Disability and Neurologic Status, assessment of signs of increased intracranial pressure and impending cerebral herniation; and E: Exposure while preventing hypothermia. Implementing these assessment and management priorities can result in more favorable outcomes. © 2015 Tehran University of Medical Sciences. All rights reserve

HIV, hepatitis C virus, and hepatitis B virus co-infections among injecting drug users in Tehran, Iran

SummaryObjectivesTo assess the prevalence of HIV, hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and co-infections among injecting drug users (IDUs) in Tehran.MethodsA sample of 899 IDUs (861 male and 38 female) was recruited in Tehran from treatment and harm reduction facilities and from drug user hangouts in public areas in equal proportions. ELISA testing for HIV, HCV antibody (HCV-Ab), hepatitis B surface antigen (HBsAg), and hepatitis B core antibody (HBcAb) was carried out. Positive HIV tests were rechecked by Western blot.ResultsThe prevalence of HIV was 10.7%, HCV infection was 34.5%, and past or current HBV infection was 50.7%. Infection with all three viruses was seen in 6.5% (95% confidence interval 4.9–8.2) of participants. HIV/HCV, HIV/HBV, and HBV/HCV co-infections were seen in 8.7%, 7.8%, and 21.0% of participants, respectively. The rate of HCV infection among HIV-positive cases was significantly higher than in HIV-negative IDUs (80.6% vs. 28.7%, p<0.0001). There was no significant association between these infections and co-infections with gender and source of sampling.ConclusionIn general, co-infection with these three blood-borne viruses is common among IDUs. Since co-infection increases the morbidity and mortality of all infections, the observed level of co-infection in the high number of IDUs in Iran necessitates a serious comprehensive response

Culture and the remembering of trauma

This research investigated the influence of culture and posttraumatic stress disorder (PTSD) on global autobiographical remembering (Study 1a) and on the phenomenological properties (Study 1b) and memory-content variables (Study 1c) of trauma-specific autobiographical remembering. Australian, British, and Iranian trauma survivors with and without PTSD completed the Autobiographical Memory Test, Self-Defining Memory Task, and Autobiographical Memory Questionnaire and provided trauma- and negative-memory narratives. We found that there were pan-cultural deficits and distortions in the global autobiographical remembering of participants with PTSD (Study 1a). In addition, the presence of PTSD moderated the usual effect of culture on the phenomenological properties of the trauma memory (Study 1b). Finally, participants with PTSD, regardless of cultural background, had significantly fewer expressions of autonomy and self-determination in their autobiographical remembering than did those without PTSD (Study 1c). The findings suggest that pan-culturally, individuals with PTSD have similar disruptions and distortions in their autobiographical remembering

Correction to: A lightweight signcryption scheme for defense against fragment duplication attack in the 6LoWPAN networks (Peer-to-Peer Networking and Applications, (2019), 12, 1, (209-226), 10.1007/s12083-018-0659-8)

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