Search

Background and objectives: Perchloroethylene (PCE) is categorized as contaminant of concern because of its adverse health effects and persistence in drinking water resources. Permeable reactive barrier with zero valent iron (ZVI-PRB) is a passive zone in which chlorinated ethenes are degraded in situ through the chemical reduction mechanism. The objective of the present investigation was optimization and modelling of ZVI-PRB technology for the elimination of PCE from the aqueous environment using response surface methodology. Materials and methods: In order to simulate ZVI-PRB, a column filled with silica sand and ZVI was used. effects of three variables including pH, column height or barrier thickness and flow on reductive dechlorination efficiency were assessed. Design of experiment, modelling, and data analysis were carried out using response surface method. Results: The dechlorination efficiency was about 93% under optimum conditions (pH=5, 26 cm column height and 2 mL/min flow rate). The ascending trend of pH along the column revealed that the reductive condition was dominant within the column. The R2 value of 0.98 also indicated good fitness of the experimental results and model predictions. Conclusion: Based on the results, ZVI-PRB technology has high efficiency in dechlorination of PCE. Likewise, regarding to no need of energy consumption, abundance of iron, no production of harmful by-products and cost-effectiveness, ZVI-PRB is propounded as a stable, green, and environmental friendly technology in groundwater remediation.

Introduction: Leakage from process equipment and the entrance of flammable fluids to surrounding atmosphere may cause flammable gas cloud. The coincidence of flammable gas cloud with ignition source could make flash fire or vapor cloud explosion that cause injury and fatality. The concept of reduction of confluence of flammable gas cloud and potential sources of ignition is known as hazardous area classification. Several standards have provided methods regarding hazardous area classification; however, of the disadvantages of them are lack of an accurate determination of hazardous areas due to potential leakage sources which is because of low flexibility in process condition variation and equipment layout and also not considering effect of weather conditions and cumulative effects of release sources. Method: In this paper, risk-based hazardous area classification is optimized using parameters such as the number of influencing release sources and weather condition probabilities. In this method, the determining factor of hazardous area boundary is the probability of acceptable ignition for every specific location. This probability is calculated using quantitative risk assessment with PHAST RISK software version 6.7 on the gas boosting unit of a gas refinery as a case study. Result: The results of this method showed the full dependency of hazardous area boundary to cumulative effects of potential sources of release and the prevailing wind direction and it also demonstrated that the suggested optimized method can consider wind direction probabilities and cumulative effects of potential sources of release in risk-based hazardous area classification calculation. Conclusion: Comparing the results of this method with the usual method determines that this method has some advantages such as considering all sources of release and cumulative sources of release and considering wind direction probabilities in determining boundary of zone 2 which makes the hazardous area classification very precise and flexible.

As waste discharge into numerous river systems escalates, the pollution of water bodies typically rises. Given the limited capacity of rivers to withstand pollution and their constrained self-cleaning capabilities, treated pollutants from waste discharge must be released into the river. Despite numerous models and algorithms proposed for managing river water quality to meet standards, literature, to our awareness, lacks the utilization of a comprehensive multi-criteria group decision-making approach for water quality management, particularly in river systems. Therefore, this research introduces a new, comprehensive multi-criteria group decision-making for the management of water quality in the Haraz River basin, located in Iran. To do so, the water quality of the basin, a one-dimensional water quality model, QUAL2Kw, was employed to simulate and calibrate the water quality along the river. The simulation results revealed that the downstream water quality violates the water quality standards. To mitigate this issue, various scenarios for waste load allocation (WLA) were evaluated, including no wastewater treatment, primary wastewater treatment, advanced secondary wastewater treatment utilizing the activated sludge (AS) method, and advanced wastewater treatment via the membrane bioreactor (MBR) method. Utilizing the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and Fuzzy TOPSIS group decision-making model, it was determined that the optimal solution was the implementation of secondary wastewater treatment utilizing the activated sludge method for the 11 PS of pollution, while still adhering to Iranian water quality standard. In addition, the findings of the present study indicate that the implementation of primary wastewater treatment, advanced secondary wastewater treatment utilizing AS, and advanced wastewater treatment through MBR within the study area led to a significant enhancement in water quality. This enhancement ranged from 35 to 105% across various scenarios when compared to conditions where no actions were taken to the treatment of water., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

In this study, a new hybrid bench-scale electrocoagulation-sand filtration (FECF) reactor was developed for purifying nitrate-contaminated samples. Before and after electrochemical treatment, two sand filters were included in this continuous system to facilitate the purification procedure, and the contaminated water flows horizontally through the entire system according to a specific hydraulic gradient within the reactor, resulting in water purification. Significant improvement in treatment performance was observed due to the presence of metal hydroxides in the second filter media that were not fully involved in the electrocoagulation treatment. Energy dispersive X-ray (EDX) analysis was performed to detect metal hydroxide species in the sand media, and the need for filter regeneration was evaluated by monitoring changes in the system flow rate. Moreover, an evaluation of the effects of different factors including operating time, current intensity, initial pH, type of anode and cathode, initial nitrate concentration, hydraulic head level inside the reactor, number of electrodes, and NaCl electrolyte concentration on the performance of nitrate removal was conducted through the Taguchi design. Further, ANOVA analysis verified the accuracy of the predicted model, and the variables were classified based on their relative importance in the FECF process. According to the regression model, 97% of nitrates were removed with Al electrodes as anode and Fe as cathode, 70 min purification time, current intensity of 3 A, 100 mg/l initial nitrate concentration, pH 8, electrolyte concentration of 1 g/l, electrode number of 6, and 1.5 cm head level., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Groundwater in arid and semi-arid coastal aquifers is vulnerable to seawater intrusion and quality deterioration despite being one of the most reliable sources of water supply due to the increasing number of development plans and competition between water consumers. A multi-dimensional groundwater management framework is developed to trade-off between groundwater abstraction, allocation equity, groundwater quality, and energy considerations in the reverse osmosis (RO) filtration process in the fresh groundwater lens of Kish Island, Iran. An arid island confined in the Persian Gulf is modeled using 3D simulation and three well-occupied multi-objective evolutionary optimization algorithms. Four objectives include: maximizing the groundwater abstraction, minimizing the Gini coefficient (allocation inequity), minimizing the total energy required to pass saline water through the RO membrane to reach the standard total dissolved solids (TDS), and minimizing the average TDS concentration of water abstraction positions from 11 management zones have been considered over a 50-year management horizon. Solutions obtained in the simulation-based constrained multi-objective optimization framework allow managers to choose from 587 Pareto optimal solutions. They provide an abstraction scheme with a range of 1.44 to 4.53 MCM/yr, a Gini coefficient of 0 to 0.98, filtration energy of 988,562 to 1,935,760 kWh/yr, and an average TDS of 19,663 to 21,351 mg/L. The Pareto optimal solutions can help decision-makers decide on the multi-dimensional problems of sustainable coastal groundwater management and show patterns among different objectives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Groundwater is a strategic source of water supply, especially in arid and semi-arid coastal regions. Growing demand, along with scarce water sources, may impose intense pressure on this precious resource. This pressure will degrade water quality for future use and cause social inequality, despite supplying current needs. A novel sustainable management model for water allocation is developed to address these interconnected concerns in coastal aquifers. Three aspects of sustainable development are considered: groundwater quality with total dissolved solids (TDS) indicator for the environmental part, gross value added from water for the economic efficiency, and the Gini coefficient for social inclusion and equity. The problem is solved with a simulation-based multi-objective optimization framework using a numerical variable-density simulation code and three approved evolutionary algorithms, NSGA-II, NRGA, and MOPSO. The obtained solutions are integrated to enhance the solutions' quality by using each algorithm's strengths and dominated members' elimination. In addition, the optimization algorithms are compared. The results showed that NSGA-II is the best in terms of solutions quality, with the least number of total dominated members (20.43%) and a 95% success rate of obtained Pareto front. NRGA was supreme in finding extreme solutions, the least computational time, and diversity, with an 11.6% higher diversity value than the second competitive NSGA-II. MOPSO was the best in spacing quality indicator, followed by NSGA-II, showing their great arrangement and evenness in obtained solution space. MOPSO has the propensity for premature convergence and needs more stringent stopping criteria. The method is applied to a hypothetical aquifer. Still, the obtained Pareto fronts are determined to assist decision-makers in real-world coastal sustainable management problems by illustrating existing patterns among different objectives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Nitrate is one of the most dangerous pollutants in groundwater, being regarded as a severe environmental hazard and a global-scale problem. The present study aims to analyze the groundwater flow and nitrate contamination in the Karaj unconfined aquifer, Central Iran. Simulation of the quantitative and qualitative status was performed using MODFLOW and MT3DMS. Sampling was done to model groundwater flow for eight seasonal time periods and nitrate pollution transport for four time periods (a total of 420 days), and calibration was carried out by trial-and-error method. Due to the predominance of advection term in the transport of nitrate pollution, the total variation diminishing method was used in transport modeling. The groundwater flow modeling showed a reservoir deficit of - 33 MCUM and 67 cm decrease in the water year 2016-2017 and 173 cm in the entire modeling period (2016-2018) in groundwater level. Also, the RMSE in the calibration and validation stages was obtained from 24.9 to 0.72 and 0.84, respectively. The nitrate contamination transport modeling indicated that there are three nitrate contamination concentration parts with more than safe concentration of nitrate (50 mg/l). The most pollution is in the urban areas in the east of the aquifer. The nitrate pollution is primarily anthropogenic due to industrial and especially domestic wastewater and then fertilizers used in agricultural activities. It can be predicted that with the full implementation of a municipal wastewater collection network, the nitrate pollution concentration in urban areas would reduce significantly to the range of 20 to 25 mg/l., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Satisfaction of patients is among the top priorities of health-care providers. Meeting with families is essential for patients who are admitted to various wards, although it has been restricted for many reasons such as its impact on physiologic indicators. This present research study aimed to exploring the influence of scheduled meetings on physiological indicators of hospitalized patients satisfaction facing acute myocardial infarction in the intensive care unit., Materials and Methods: This study was a nonrandomized clinical trial with a control group conducted in the cardiac care unit ward of Hamadan's Ekbatan Hospital. Sixty patients with acute myocardial infarction were chosen through convenient sampling and assigned to intervention (planned meeting) and control (routine meeting) groups in a nonrandomized manner. Data were collected by a researcher-made questionnaire of patient satisfaction and the observatory checklist of physiologic indicators and then analyzed in IBM SPSS Statistics v23., Results: The total mean score of satisfaction did not significantly differ between the two groups ( P = 0.921). The satisfaction of patients for "the conduct of visitors" was significantly higher in the intervention group ( P = 0.005). During the study, no meaningful difference was found between the two groups for physiologic indicators ( P > 0.05), while these indicators, except for blood O2 saturation, were meaningfully increased in the control group during routine meetings ( P < 0.05)., Conclusion: Planned meetings did not promote total satisfaction of patients with meetings, but improved some aspects of satisfaction, such as the conduct of visitors. The planned meeting is recommended as an alternative for a routine meeting, as it did not affect the physiologic indicators of patients in the intervention group., Competing Interests: The authors declare no conflict of interest., (Copyright: © 2022 Journal of Education and Health Promotion.)

Introduction: Augmentation of the number of trained basic life support (BLS) providers can remarkably reduce the number of cardiac arrest victims. The aim of this study was to evaluate the level of BLS awareness among students of medical sciences in Iran., Methods: This multicenter cross-sectional study was performed on medical students at the 4 major medical schools in Tehran, the capital of Iran, between Jan 2018 and Feb 2019, using convenience sampling method. The level of medical sciences students' awareness of BLS was measured using an international questionnaire., Results: Finally, 1210 students with the mean age of 21.2 ± 2.3 years completed the survey (79% female). 133 (10.9%) students had CPR experience and none had received any formal training. None of the responders could answer all questions correctly. The mean awareness score of participants was 11.93 ± 2.87 (range: 10.13 -17.25). The awareness score of participants was high in 49 (4.04 %) participants, moderate in 218 (18.01%), and low in 943 (77.93%) of studied cases., Conclusion: Based on the findings of this study, more than 70% of the studied medical sciences students obtained a low score on BLS awareness., Competing Interests: None to Declare.

Background: Chemotherapy plays a very important role in the treatment of leukemia but the resistance properties of the lymphoblasts limit the effect of chemotherapy. One of the main mechanisms of resistance to chemotherapy is the increased expression of MDR1 gene. The aim of this study was to explore the effect of resveratrol on the expression of MDR1 gene in leukemic lymphoblast of new cases of acute lymphoblastic leukemia (ALL) patients in vitro., Methods: Separation of lymphoblasts of 5 new case ALL patients from peripheral blood was performed by ficoll density gradient centrifugation. Lymphoblasts were cultured in RPMI 1640 medium. Lymphoblasts were treated with 50µmol/L resveratrol for 48 h. Total RNA was extracted with guanidine isothiocyanate. RNA was converted to cDNA. Real time PCR was used to detect mRNA expression of MDR1., Results: The results of gene detection showed that the expression of MDR1 did not change significantly in the patients however, in one patient expression of MDR1 increased upon treatment with resveratrol., Conclusion: The results of this study did not support resveratrol as a compound to reverse multidrug resistance in leukemic lymphoblasts.

Hexavalent chromium Cr(VI) is of particular environmental concern due to its toxicity, mobility, and challenging removal from industrial wastewater. It is a strong oxidizing agent that is carcinogenic and mutagenic and diffuses quickly through soil and aquatic environments. Moreover, it does not form insoluble compounds in aqueous solutions; therefore, separation by precipitation is not feasible. While Cr(VI) oxyanions are very mobile and toxic in the environment, trivalent Cr(III) cations are the opposite and, like many metal cations, Cr(III) forms insoluble precipitates. Thus, reducing Cr(VI)-Cr(III) simplifies its removal from effluent and also reduces its toxicity and mobility. Permeable reactive barriers (PRBs) with zero-valent iron (ZVI) have been used to remediate contaminated groundwater with metals, but using ZVI in remediation of contaminated groundwater or wastewater is limited due to its lack of stability, easy aggregation, and difficulty in separation of iron from the treated solution. Thus, the technology used in the present study is developed to address these problems by placing a layer of bentonite after the PRB layer to remove iron from the treated water. The removal rates of Cr(VI) under different values of pH were investigated, and the results indicated the highest adsorption capacity at low pH.

Image pattern classification is a challenging task due to the large search space of pixel data. Supervised and subsymbolic approaches have proven accurate in learning a problem's classes. However, in the complex image recognition domain, there is a need for investigation of learning techniques that allow humans to interpret the learned rules in order to gain an insight about the problem. Learning classifier systems (LCSs) are a machine learning technique that have been minimally explored for image classification. This work has developed the feature pattern classification system (FPCS) framework by adopting Haar-like features from the image recognition domain for feature extraction. The FPCS integrates Haar-like features with XCS, which is an accuracy-based LCS. A major contribution of this work is that the developed framework is capable of producing human-interpretable rules. The FPCS system achieved 91 [Formula: see text] 1% accuracy on the unseen test set of the MNIST dataset. In addition, the FPCS is capable of autonomously adjusting the rotation angle in unaligned images. This rotation adjustment raised the accuracy of FPCS to 95%. Although the performance is competitive with equivalent approaches, this was not as accurate as subsymbolic approaches on this dataset. However, the benefit of the interpretability of rules produced by FPCS enabled us to identify the distribution of the learned angles-a normal distribution around [Formula: see text]-which would have been very difficult in subsymbolic approaches. The analyzable nature of FPCS is anticipated to be beneficial in domains such as speed sign recognition, where underlying reasoning and confidence of recognition needs to be human interpretable.

This research is part of an ongoing selection and breeding effort to target Iranian genotypes of Hypericum perforatum with the potential to produce higher amounts of desired secondary metabolites and greater resistance to fungal pathogens. There is a significant interest in the development of such cultivars to supply materials to the local pharmaceutical industries. For this reason, two improved cultivars of H. perforatum ("Gold" and "Veperikon") were compared with a wild Iranian population (Ardabile population) under common garden conditions in Iran. Plants were cultivated from seed in a greenhouse and seedlings were transplanted after one month to the field plots. The statistical design of this study was a Randomized Complete Block Design with three replications. During the period of full flowering, selected phenological (number of days to flowering), morphological (plant height, mean leaf area, number of black glands/leaf) and chemical (hypericin and pseudohypericin content) characteristics were assessed. Our observations were that the "Veperikon" cultivar is very sensitive to soil-borne diseases. All transplanted seedlings were infected by the plant pathogenic fungus Colletotrichum gloeosporioides, which caused necrosis of the whole plant. Both the "Gold" cultivar and plants from the wild population persisted despite mild infections with C. gloeosporioides and produced flowering shoots at both the first and second years after cultivation. The "Gold" cultivar was superior to the Ardabile population in terms of phenological and morphological characteristics. The average naphthodianthrone content (% dry weight of tissue) for the wild Iranian population was 0.04(±0.01)%, but for the "Gold" cultivar, 0.33(±0.43)%. These data indicate that selection and directed cultivation of Iranian H. perforatum plants can result in plants with improved morphological, phenological and chemical characteristics.