Microbial desalination cells with efficient platinum group metal-free cathode catalysts

Iron-nitrogen-carbon based catalyst was used at the cathode of a microbial desalination cell (MDC) and compared with platinum (Pt) and activated carbon (AC) cathode. Fe-N-C catalyst was prepared using nicarbazin (NCB) as organic precursor by sacrificial support method (SSM). Rotating ring disk electrode (RRDE) experiments shows that Fe-NCB had higher electrocatalytic activity compared to AC and Pt. The utilization of Fe-NCB into the cathode improved substantially the performance output with initial maximum power density of 49±2 μWcm-2 in contrast to Pt and AC catalysts which have shown lower values of 34±1 μWcm-2 and 23.5±1.5 μWcm-2, respectively. After four cycles, Fe-NCB catalyst lost 15% of its initial performance but still was 1.3 and 1.8 times more active than Pt and AC, respectively. Solution conductivity (SC) inside the desalination chamber (DC) decreased by 46-55% with every cycle. The pH of the cathodic chamber (CC) and the DC increased up to 10-11 due to the production of OH- during the oxygen reduction reaction and the migration of OH- into the desalination chamber. Chemical organic demand (COD) decreased by 73-83% during each cycle. It was shown that Fe-NCB and Pt had a similar coulombic efficiency (CE) of 39±7% and 38±2%, while AC had lower CE (24±5%)

DIRAC OPERATORS ON LIE ALGEBROIDS

We compare the Dirac operator on transitive Riemannian Lie algebroid equipped by spin or complex spin structure with the one defined on to its base manifold‎. Consequently we derive upper eigenvalue bounds of Dirac operator on base manifold of spin Lie algebroid twisted with the spinor bundle of kernel bundle‎

THE RELATIONSHIP BETWEEN ORGANIZATIONAL CLIMATE AND MENTAL HEALTH OF THE STAFF IN THE DEPARTMENT OF SPORT AND YOUTH OF GILAN PROVINCE, IRAN

The purpose of this study was to determine the relationship between organizational climate and mental health in the staff of the Department of Sports and Youth of Gilan Province. The present research is a descriptive – correlational research. In terms of purpose, this study is applied research and the data were collected in a cross sectional study in 2017. The population of this study included all male and female experts in the department of sport and youth in Gilan province, which 123 individuals were randomly selected using Morgan table. The data collection tool was a standard organizational climate questionnaire and mental health questionnaire. The content validity as well as the form of the questionnaire were approved by the experts and the reliability of the standard questionnaires in this study was 0.83 and 0.88, respectively. Descriptive statistics and Kolmogorov-Smirnov tests, Pearson correlation and linear regression tests were used for data analysis. The results of this study showed that there is a significant relationship between organizational climate with mental health and its components such as depression, anxiety, physical complaints, psychosis, allergy and aggression of research samples. The results of linear regression also showed that about 59% of the dependent variable variations (mental health) are related to the independent variable (organizational climate). Finally, since the relationships between variables are confirmed, it is suggested that to provide a healthy and intimate atmosphere and increase and maintain the morale and reduce the incidence of mental disorders of the employees  and consequently, the obligated performance of individuals in order to attain the goals of the department of the sport and youth of Gilan province.  Article visualizations

An Investigation into the Role of Nano-Silica in Improving Strength of Lightweight Concrete

Development of technology and human’s access to nanotechnology brings about the necessity to use nanotechnology in the concrete industry. Since the decrease of particles size leads to new properties, and unusual mechanical, electrical, and magnetic properties which are inaccessible in usual state, nanotechnology is highly considered. The emergence of nanotechnology in concrete industry has made great changes in many of the concrete properties. Dead load resulted from weight of ceilings and separation walls is one of the fundamental problems in seismic design and structures implementation especially in tall buildings. Obviously, using the lightweight materials could decrease the dead load, weight of beams, columns, and foundation. However, low compressive resistance of lightweight concrete mostly has a direct ratio with the specific gravity of it. Lightweight concrete has a low resistance as a result of its low specific weight. Silica nanoparticles (SNs) have a high surface energy as a result of their high specific surface.  Therefore, they are supposed to have a high pozzolanic reaction and they accelerate hydration reactions. Since the increase of concrete compressive strength is highly noticeable in the new technology, the increase of effective materials with the purpose of increasing compressive strength of concrete could increase the life circle of concrete structures. The present paper intends to investigate the effect of silica nanoparticles on compressive strength, tensile strength, bending strength, contraction of lightweight concrete, and concrete microstructure

The effect of 2 nitroglycerin ointment application on the phlebitis intensity, induced by intravenous catheter

چکیده: زمینه و هدف: شیوع بالای عارضه فلبیت یکی از مسایل مهم در رابطه با تزریقات وریدی می باشد. در بیمارستان هایی که میزان عوارض ناشی از تزریقات وریدی کمتر بوده، مدت اقامت بیماران در بیمارستان و همچنین موارد مرگ و میر کاهش چشمگیری داشته است. این مطالعه با هدف بررسی تاثیر کاربرد پماد نیتروگلیسرین 2 بر شدت فلبیت ناشی از کاتتر وریدی انجام شده است. روش بررسی: در این مطالعه کارآزمایی بالینی یک سو کور 300 نفر از بیماران بستری در بخش قلب و سی سی یو بیمارستان قائم شهر مشهد به روش مبتنی بر هدف انتخاب و به صورت تصادفی در دو گروه شاهد و آزمون قرار گرفتند. در گروه آزمون پس از جایگذاری کاتتر وریدی در قسمت دیستال کاتتر پماد نیتروگلیسرین 2 به میزان 5/0 اینچ گذاشته و پانسمان می‌شد و در گروه شاهد جایگذاری کاتتر وریدی بدون استفاده از پماد نیتروگلیسرین انجام شد. پس از جایگذاری کاتتر هر 12 ساعت محل کاتتر از نظر وجود علایم فلبیت بررسی و در گروه آزمون پانسمان پماد نیتـــروگلیسرین تعـویض می‌شد. داده های به دست آمده به کمک آزمون های آماری t مستقل، کای دو و آزمون دقیق فیشر تجزیه و تحلیل شد. یافته ها: شدت فلبیت در گروه آزمون کمتر از گروه شاهد بود (001/0

Effects of positioning on patients back pain and comfort after coronary angiography

چکیده: است زمینه و هدف: آنژیوگرافی استاندارد طلایی جهت تشخیص قطعی بیماری های عروق کرونر می باشد. پس از آنژیوگرافی جهت جلوگیری از خونریزی از ناحیه ورود کاتتر، بیمار باید به مدت چند ساعت (8 تا 24 ساعت) استراحت مطلق (در وضعیت خوابیده به پشت) در تخت بماند که با مشکلاتی همچون ایجاد کمردرد و ناراحتی برای بیماران همراه است. هدف از این مطالعه بررسی تأثیر یک روش نوین پوزیشن دهی بر میزان درد و راحتی بیماران بعد از انجام آنژیوگرافی عروق کرونر و میزان بروز عوارض می‌باشد. روش بررسی: این پژوهش یک مطالعه نیمه تجربی می باشد که پس از نمونه گیری به روش در دسترس، نمونه ها (70 نفر) به صورت تصادفی به دو گروه 35 نفره شاهد و آزمون تخصیص داده شدند. گروه آزمون با استفاده از یک روش نوین پوزیشن دهی ترکیبی (متشکل از تغییر پوزیشن همزمان با تغییر زاویه سر تخت و در نهایت خارج کردن زود هنگام بیمار از تخت) و گروه شاهد طبق پروتکل رایج (خوابیده به پشت و سر تخت صاف) پوزیشن داده شدند. شدت درد و میزان راحتی با استفاده از مقیاس های دیداری و میزان خونریزی و هماتوم با استفاده از خط‌کش طراحی شده اندازه‌گیری شدند و داده ها با استفاده از آزمون های آماری t، مجذور کا، آنالیز واریانس یک طرفه، آنالیز واریانس با اندازه های مکرر و آزمون همبستگی تجزیه و تحلیل شدند. یافته ها: بین دو گروه از نظر مشخصات دموگرافیک سابقه انجام آنژیوگرافی، نوع تشخیص بعد از آنژیوگرافی، کمر درد، میزان راحتی و میزان خونریزی در بدو ورود به بخش، اختلاف معنی‌داری وجود نداشت. یافته ها نشان داد شدت درد در ساعت سوم، ششم و هشتم و صبح روز بعد از آنژیوگرافی به میزان معنی‌داری در گروه شاهد بیش از گروه آزمون و میزان راحتی به میزان معنی‌داری در گروه آزمون بیشتر از گروه شاهد می باشد (01/0>p). میزان خونریزی و حجم هماتوم در دو گروه تفاوت معنی‌داری با یکدیگر نداشت (05/

The relationship between body mass index and preeclampsia: A systematic review and meta-analysis

Background: One of the causes of maternal and fetal mortality and morbidity is pregnancy-induced hypertension, the most common form of which is preeclampsia that causes many complications for mother and fetus. Objective: The aim of this systematic review and meta-analysis was to determine the relationship between body mass index (BMI) and preeclampsia in Iran. Materials and Methods: Using valid keywords in the SID database, PubMed, Scopus, data obtained from all the articles, which were reviewed in Iran between 2000 and 2016, were combined using the meta-analysis method (random-effects model) and analyzed using STATA version 11.1. Results: A total number of 5,946 samples were enrolled in 16 studies with the mean BMI values of 25.13, 27.42, and 26.33 kg /m2 in the healthy, mild, and severe preeclamptic groups, respectively. Conclusion: The results of this study revealed that there is a significant relationship between BMI and the risk of preeclampsia, so it can be said that BMI may be one of the ways to diagnose preeclampsia

Prediction of Optimum Gas Mixture for Highest SXR Intensity Emitted by A 4kj Plasma Focus Device Using Artificial Neural Network

In this study, artificial neural network (ANN) is investigated to predict the optimum gas mixture for highest soft X-ray (SXR) intensity emitted by a 4kJ plasma focus device. To do this multi-layer perceptron (MLP) neural network is used for developing the ANN model in MATLAB 7.0.4 software. In this model, the input parameters are voltage, Percentage of nitrogen in admixture and pressure and the output is SXR intensity. The obtained results show that the proposed ANN model has achieved good agreement with the experimental data and has a small error between the estimated and experimental values. Therefore, this model is a useful, reliable, fast and cheap tool to predict the optimum gas mixture for highest SXR intensity emitted by plasma focus devices