Hydrogen technology through water electrolyzer systems has attracted a great attention to overcome the energy crisis. So, rationally designed non-noble metal based-electrocatalysts with high activity ...and durability can lead to high performance water electrolyzer systems and high purity hydrogen generation. Herein, a facile two-step method: hydrothermal and electrodeposition, respectively, are developed to decorate highly porous three-dimensional binder-free structure NiFeO/NiO nanosheets array on Ni foam (NiFeO/NiO/NF) with robust adhesion as a high-performance electrode for Hydrogen Evolution Reaction (HER).
The electrodeposition process applied after the initial hydrothermal process provides a stable structure and, in addition, enhances the sluggish hydrogen evolution efficiency. In alkaline media, the developed electrode needs an overpotential of 48 and 188 mV to drive current densities (j) of 10 and 100 mA cm−2, respectively. After continuous 110 h electrochemical stability test under j = 150 mA cm−2 conditions, demonstrates an excellent stability with ignorable activity decrease. Such superior HER catalytic performance can be derived from the synergistic effect between Ni and Fe atoms, also exposure to a high number of active sites on the nanosheets, and good dynamic with effective electron transport along the nanosheets. The present work provides a promising route for the design and fabrication of cost-effective and highly efficient HER electrocatalysts.
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•3D binder-free NiFeO-10/NiO/NF electrocatalyst with nanosheets array has been designed for HER.•The NiFeO-10/NiO/NF exhibits excellent electrocatalytic activity and superior durability for HER.•NiFeO-10/NiO/NF activity is better than that of NiFe-LDH-10/NF and NiO/NF.•The current density of 10 mA cm−2 was achieved at a small overpotential of 48 mV.
The aim of this study was to evaluate the groundwater quality Indices of Groundwater resource for Agricultural Use in jolfa city (Iran) during one decade (2003–2013). Data showed in the first and end ...year of the study period, the Mean±SD of Sodium Adsorption Ratio (SAR) and Sodium Percentage (Na%) indices 5455.77±3878.02, 3638.69±3565.19 and 51.49±15.65, 41.58±17.69, respectively. The data indicate that the, in terms of sodium percentage and sodium adsorption ratio, the water quality in this area is not suitable for irrigation.
In this study, a 2D mathematical model was developed for both arc and weld pool in stationary GTA welding. In arc model, current continuity equation has been solved in both arc and cathode regions ...without any assumption of fixed current density on the cathode surface which was essential in most previous works. The results of arc model were presented for both copper and aluminum anodes to investigate the effect of anode material on arc properties. It was seen that aluminum anode has lower maximum anode current density and heat flux but the distributions are wider than copper anode. Furthermore, shear stress on anode surface is higher in the case of aluminum anode. Also, calculated results of this study were compared with other available theoretical and experimental results. It has been shown that the agreement between calculated and experimental results was fairly good. The necessary information to simulate the weld pool, including the anode current density and heat flux to the workpiece were taken from the arc model. In this model, due to high thermal conductivity of pure aluminum, fluid flow into the weld pool was ignored. Effects of arc variables, i.e., arc length, applied current and welding time on the shape and size of the weld pool were investigated as well. In order to check the validity of the weld pool model, a comparison between calculated results and the results of our experimental tests was conducted. Generally, these comparisons reveal an acceptable agreement between calculated results and experimental data.
The aim of this study is to determine the Aluminum concentration in groundwater resources of Sistan and Baluchestan province, Iran. See the data in this article. For the purpose of this study, a ...total of 871 water samples were collected and values of quality parameters including pH, turbidity, total dissolved solids (TDS) and Aluminum concentration were measured (with two-time repetitions) according to Standard Methods for the Examination of Water and Wastewater, during the year 2016. The mean, maximum, minimum of Aluminum concentrations in all groundwater resources of Sistan and Baluchistan province, were: 0.015, 0.059, 0.0004 mg/l, respectively and also, the standard deviation was 0.012. Moreover, employing GIS software, the geo-statistical distribution of Aluminum concentration in groundwater aquifer in Sistan and Baluchestan was mapped.
Aims: Nitrate can enter water bodies through using chemical fertilizers and discharging the effluents from municipal and industrial sewage treatment plants. As a superiority to the conventional ...statistical models, Grey models (GMs) require only a limited amount of representative data to estimate the behavior of unknown systems. In the current study, the nitrate concentration of the year 2023 in Babol groundwater resources was forecasted by using GM, namely GM (1, 1). Materials and Methods: This descriptive-cross-sectional study was performed in the city of Babol. The data of 63 wells in urban and rural areas during the warm and cold seasons between 2007 and 2017 were supplied from the Health Center and Babol Rural Water and Sewage Company. In data set, the observed values between 2007 and 2015 were used to fit models, and the observed values between 2016 and 2017 were used to evaluate the accuracy of the model's predictions. To assess the efficiency of the model fitted and precision of the predicted values, we used indexes of forecast absolute error, small error probability, and the proportion of variance statistical metrics. Results: Simulated results showed that the accuracy of the model GM (1, 1) to predict and forecast both data sets is entirely appropriate and reliable. The forecasting values of nitrate concentration of the year 2023 and 8 years later, for urban and rural areas in warm and cold seasons, are 21.30 and 7.30 and 15.63 and 5.34 mg/L, respectively. Conclusion: Although the predicted concentration of nitrate in the studied area is lower than that the standard concentration suggested by the World Health Organization, all water resources should be protected effectively.
The residual chlorine and microbial quality of drinking water in the Zahedan villages by a number of1221 samples from all 168 villages were collected between 2014–2015. Then the samples were ...evaluated using 9-tube fermentation methods and portable chlorine method test. Based on the microbial coliform and fecal coliform indices, the data indicated that the maximum and minimum controlling of the bacteria in the distribution network were in the winter (90.62%) and autumn (85.56%), respectively. Also in the reservoirs, the maximum and minimum controlling of the bacteria were in winter (93.49%) and autumn (87.35%), respectively. The residual chlorine was prepared in almost all of seasons.
The current study aimed to evaluate the efficacy of sitagliptin vs. placebo in treating non-alcoholic fatty liver disease (NAFLD). In a triple-blind randomized clinical trial, we assigned 120 ...eligible subjects with NAFLD to receive daily dosing of 50 mg sitagliptin (
n
= 60) or the placebo (
n
= 60) for 56 weeks and lifestyle modification in both groups. Laboratory and anthropometric outcomes were measured, and liver stiffness was assessed using a fibroscan. The primary outcome measures were changes from baseline in fibrosis scores and liver transferases. Out of 120 patients randomized into sitagliptin and placebo groups, 76 patients completed the trial, of whom 44 were in the sitagliptin and 32 in the placebo groups. Patients receiving sitagliptin showed a significant decrease in the fibrosis scores (
P
= 0.001). The reductions in the alanine aminotransferase (AST) (
P
= 0.036) and aspartate AST (
P
< 0.001) levels were also statistically significant. The effect of sitagliptin in reducing fibrosis scores was significantly greater in normal-weight and overweight individuals than in obese individuals (
p
= 0.036, and
p
= 0.018, respectively), whereas the effects of sitagliptin on AST levels were greater among overweight/obese patients (
p
= 0.028, and
p
= 0.016, respectively). Sitagliptin reduced fibrosis scores and liver enzymes in NAFLD patients after 56 weeks of therapy. The changes in fibrosis scores were more prominent in patients with normal weight and overweight than obese patients, whereas the effects on AST levels were greater among overweight/obese patients. Other randomized trials with larger sample sizes and longer treatment durations may be required before precise results can be reached.
Clinical Trial Registration
https://www.irct.ir/trial/46140
, identifier IRCT20140430017505N2.
Globally, most people die from cardiovascular diseases. We aimed to compare predictive ability of six obesity indices, including body mass index, waist circumference, waist-to-hip ratio, ...waist-to-height ratio, conicity index, and abdominal volume index, to identify people at risk of fatal and non-fatal cardiovascular events, in a cohort study.
We studied 5147 participants in a baseline population-based cohort study conducted in northern Iran. The obesity measures were calculated in enrollment phase (2009–2010), and the cardiovascular events were recorded during a 7-year follow-up phase (2010–2017). Receiver operating characteristic (ROC) analyses and Cox hazard regression models were applied, considering the obesity measures as predictors, and the 7-year cardiovascular events as outcomes. Multiple Cox models were adjusted by age, prior history of cardiovascular diseases, chronic kidney diseases, insulin resistance, diabetes mellitus, dyslipidemia, hypertension, and smoking status.
Conicity index showed the highest performance in predicting 7-year fatal and non-fatal cardiovascular events with areas under the ROC curve of 0.77 95% confidence interval: 0.71–0.82, and 0.63 0.59–0.68 in men, and 0.80 0.74–0.87, and 0.65 0.60–0.71 in women, respectively. In multiple Cox models, the obesity measures had no significant associations with cardiovascular events in women. In men, only waist-to-height ratio was independently associated with 7-year non-fatal cardiovascular events (hazard ratio: 1.19 95% confidence interval: 1.01–1.38).
Although waist-to-height ratio had an independent association with 7-year non-fatal cardiovascular events in men, conicity index showed the best ability to predict 7-year fatal and non-fatal cardiovascular events in our study.
Dietary modifications remain the mainstay in managing nonalcoholic fatty liver disease (NAFLD). Published data on the effect of overall dietary patterns on NAFLD is scarce. The present study aims to ...extract the dietary patterns and investigate their association to NAFLD by gender, using structural equation modeling, among adult participants in Amol, northern Iran. In this cross-sectional study, data from 3,149 participants in the Amol cohort study (55.3% men,
= 1,741) were analyzed. Usual dietary intake was assessed by a validated 168-items semiquantitative food frequency questionnaire. We classified major dietary patterns by explanatory factor analysis (EFA) and confirmatory factor analysis (CFA). NAFLD diagnosis was based on ultrasound scanning, including increased hepatic echogenicity, abnormal appearance of hepatic arteries, and diaphragm in the absence of excessive alcohol consumption. Multivariable logistic regression and structural equation modeling (SEM) were used to explore the relationship between dietary patterns and NAFLD. Three distinct dietary patterns, including western, healthy, and traditional/mixed dietary patterns, were identified. Adult male who adhere to the western dietary pattern were more affected with NAFLD risk Q1, Q2, Q3, Q4, odds ratio
= 1, 1.16, 1.34, 1.39; 95% confidence interval
= 0.83-1.61, 0.96-1.85, 0.98-1.96,
= 0.04, respectively. A full mediating effect of healthy dietary pattern, western dietary pattern, and traditional dietary pattern
dietary acid load (DAL) proxy (of dietary patterns to DAL: βstd = -0.35,
< 0.006, β
= 0.15,
= 0.009, and β
= 0.08,
= 0.001, respectively), on NAFLD was found through mediation analysis using SEM. A western dietary pattern comprising frequent intake of salty and sweet snacks, soft drinks, refined grains, processed meats, cooked and fried potatoes, eggs, and coffee was associated with a higher odds of NAFLD in an Iranian male population. Additionally, our findings might provide a mechanistic explanation for the association between dietary patterns and NAFLD
DAL proxy. However, further prospective studies, including assessing acid-base biomarkers, are needed.
The pooled cohort equations of the American College of Cardiology/American Heart Association (ACC/AHA) and the Framingham general cardiovascular risk profile (for use in primary care) were developed ...using some CVD risk factors including age, history of diabetes mellitus (DM), current smoking status, systolic blood pressure (SBP), total cholesterol and high density lipoprotein (HDL) in men and women, separately.8,9 Two versions of the Systematic Coronary Risk Evaluation (SCORE) equations were also developed according to the abovementioned risk factors, except for HDL and history of DM.10 None of the obesity indices are utilized in the abovementioned CVD risk assessment tools, Although, there are several simple indices to evaluate obesity, none of the obesity indices are utilized to predict the 10-year CVD risk in the abovementioned CVD risk assessment tools. Since the obesity paradox was confirmed for some CVD outcomes based on some obesity indices, particularly BMI, we aimed to determine whether the obesity paradox would be detectable when the 10-year risk of CVD and obesity are determined by mentioned risk assessment tools and obesity indices, respectively. Informed consent was obtained from all study subjects, and the study was approved by the Ethics Committee of Iran University of Medical Sciences, Iran. Since the risk assessment tools are generally applied to the population aged 40-74 years (8-10), the data of 2910 subjects (1623 men and 1287 women) aged 40-74 years were utilized in this study. The proportion of individuals who had a 10-year risk of CVD > 7.5% based on ACC/AHA, > 5% based on SCORE equations (low and high risk European countries), and > 10% based on Framingham approach were compared between the groups with and without obesity using independent two group proportion test. Since the 10-year risk of CVD was estimated based on 4 risk assessment tools and obesity was determined according to 4 indices, 16 two group proportion tests were performed in men and women, separately. ...several logistic regression analyses were separately performed in which each of the categorized obesity indices was considered a predictor and a 10-year risk of CVD > 7.5%, > 5%, and > 10% was considered an outcome based on pooled cohort equations, SCORE equations, and the Framingham tool, respectively.
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