200 research outputs found
Evaluation of dairy industry wastewater treatment and simultaneous bioelectricity generation in a catalyst-less and mediator-less membrane microbial fuel cell
Increased human activity and consumption of natural energy resources have led to decline in fossil fuel. These current methods of energy production are not compatible with the environment. In this study catalyst-less and mediator-less membrane microbial fuel cell (CAML-MMFC) represents a new method for simultaneous dairy industry wastewater treatment and bioelectricity generation. The CAML-MMFC used was designed as two chambered that included an anaerobic anode and aerobic cathode compartment and was separated from each other by a proton exchange membrane. The anode and cathode electrodes were made from graphite plate. Current intensity, power density and voltage produced from wastewater as fuel were measured and the effluent from the anode compartment was examined to evaluate pollutant decrease. The maximum current intensity and power density produced were respectively 3.74 mA and 621.13 mW/m2 on the anode surface, at OLR equal to 53.22 kgCOD/m3 d and at the external resistance of 1 k Ω. The maximum voltage produced was 0.856 V at OLR equal to 53.22 kgCOD/m3 d and at temperature 35oC. The maximum coulombic efficiency of 37.16 was achieved at OLR equal to 17.74 kgCOD/m3 d. The HRT was examined as a factor influencing the power generation and when it was 5 day, maximum voltage and power density were obtained. The maximum removal efficiency of COD, BOD5, NH3, NH4 +, dissolved phosphorus, phosphorus in suspended solids, SO4 2-, TSS, and VSS was respectively achieved at 90.46, 81.72, 73.22, 69.43, 31.18, 72.45, 39.43, 70.17 and 64.6. The results showed that generating bioelectricity and dairy industry wastewater treatment by CAML-MMFC are a good alternative for producing energy and treating wastewater at the same time. © 2014 King Saud University. Production and hosting by Elsevier B.V
Nurses' Requirements for Relief and Casualty Support in Disasters: A Qualitative Study
Background: Nurses are among the most important groups engaged in casualty support, regardless of the cause, and they are one of the largest care groups involved in disasters. Consequently, these workers should gain proper support and skills to enable effective, timely, responsible and ethical emergency responses.
Objectives: In this study, we investigated the needs of nurses for proper casualty support in disasters, to facilitate better planning for disaster management.
Materials and Methods: This was a qualitative content analysis study. Interviews were performed with 23 nurses, at educational hospitals and the Faculty of Nursing at Kerman Medical University, who had a minimum of five years working experience and assisted in an earthquake disaster. Intensity and snowball sampling were performed. Data was collected through semi-structured interviews. Interviews were transcribed and coded into main themes and subthemes.
Results: Four major themes emerged from the data; 1) psychological support, 2) appropriate clinical skills education, 3) appropriate disaster management, supervision and programming, and 4) the establishment of ready for action groups and emergency sites. The participants’ comments highlighted the necessity of training nurses for special skills including emotion management, triage and crush syndrome, and to support nurses' families, provide security, and act according to predefined programs in disasters.
Conclusions: There are a wide range of requirements for disaster aid. Proper aid worker selection, frequent and continuous administration of workshops and drills, and cooperation and alignment of different governmental and private organizations are among the suggested initiatives
Interest in rhinoplasty and awareness about its postoperative complications among female high school students
Introduction: Rhinoplasty is a popular cosmetic surgical procedure. Informal statistics show that Iran has one of the highest rates of rhinoplasty in the world. However, rhinoplasty like any other surgery can have complications. Materials and Methods: In this cross-sectional study, 320 female students were selected by multistage cluster-stratified sampling from high schools in Kerman, Iran and each completed a questionnaire. Results: More than half of the students said they would like to undergo rhinoplasty. The main reasons for wanting rhinoplasty were beauty and because it is fashionable. However, more than half of the interested students did not know about the possible postoperative complications of rhinoplasty. There was no relation between interest in having rhinoplasty and parents' education, city of birth or economic status. Conclusion: Many teenagers are interested in having rhinoplasty in Iran. As the number of teenagers and young adults who choose to have cosmetic surgery increases, surgeons should consider their expectations, motivations and awareness of postoperative complications before surgery
Efficiency of multi walled carbon nanotubes for removing Direct Blue 71 from aqueous solutions
Dye wastewater produced from industrial activity is usually toxic, resistant to biodegradation and persistent in the environment. The aim of this study was to evaluate the efficiency of multiwalled carbon nanotubes (MWCNTs) for decolorization of Direct Blue 71 (DB71). In this experimental study, the effect of various variables including contact time, solution pH, adsorbent dose, and initial dye concentration was evaluated in a batch reactor. The adsorption and kinetic models were evaluated to explain the adsorbed dye and dynamic reaction. The results of this study showed that the efficiency of dye removal increased, as the contact time and adsorbent dose increased, but as pH and initial dye concentration increased, removal efficiency decreased. The maximum efficiency of Direct Blue 71 removal was observed at acidic solution (pH=3), contact time of 90 minutes, adsorbent dose of 0.6 g/l and initial dye concentration of 25 mg/l. The adsorption of direct blue 71 best fitted the Langmuir isotherm (R2=0.87) and pseudo first order kinetic equation (R2=0.99). According to the results obtained, multiwalled nanotubes was offered as an effective adsorbent for removing direct blue 71. © Authors
The relationship between religion and risky behaviors among Iranian university students
One factor that protects an individual from risky behavior is religiosity, which is referred to as a shield against risky behaviors. Belief in God and religion plays an important role in young people’s lives, and in comparison with their non-religious peers. They engage less frequently in risky behaviors, such as violence and sexual relations. The present study investigated the relationship between religiosity and engagement in risky behaviors among students from the Pishva branch of the Islamic Azad University, Tehran Province in Iran. This is a descriptive, analytic cross-sectional study. The sample was comprised of 448 students from different degree majors attending the University. Participants completed two questionnaires, including the Risk-Taking Scale and Duke University Religion Index. The data analyses used one-way ANOVAs and Pearson’s correlations. This study found that students who engaged more often in organized religious activities and had higher intrinsic religiosity were less likely to engage in risky behaviors such as sexual risk taking, careless driving, violence, smoking, along with alcohol and drug abuse. Participants with higher involvement in private religious activities reported lower tendencies for the above-mentioned risky behaviors, except sexual risk taking. The findings of this study indicate that the different dimensions of religiousness are related to students’ tendency to avoid risky behavior. Thus, it appears that religion may have a role to play in preventing risky taking behavior in Iran
Multiple air pollutant exposure and lung cancer in Tehran, Iran
Lung cancer is the most rapidly increasing malignancy worldwide with an estimated 2.1 million cancer cases in the latest, 2018 World Health Organization (WHO) report. The objective of this study was to investigate the association of air pollution and lung cancer, in Tehran, Iran. Residential area information of the latest registered lung cancer cases that were diagnosed between 2014 and 2016 (N = 1,850) were inquired from the population-based cancer registry of Tehran. Long-term average exposure to PM10, SO2, NO, NO2, NOX, benzene, toluene, ethylbenzene, m-xylene, p-xylene, o-xylene (BTEX), and BTEX in 22 districts of Tehran were estimated using land use regression models. Latent profile analysis (LPA) was used to generate multi-pollutant exposure profiles. Negative binomial regression analysis was used to examine the association between air pollutants and lung cancer incidence. The districts with higher concentrations for all pollutants were mostly in downtown and around the railway station. Districts with a higher concentration for NOx (IRR = 1.05, for each 10 unit increase in air pollutant), benzene (IRR = 3.86), toluene (IRR = 1.50), ethylbenzene (IRR = 5.16), p-xylene (IRR = 9.41), o-xylene (IRR = 7.93), m-xylene (IRR = 2.63) and TBTEX (IRR = 1.21) were significantly associated with higher lung cancer incidence. Districts with a higher multiple air-pollution profile were also associated with more lung cancer incidence (IRR = 1.01). Our study shows a positive association between air pollution and lung cancer incidence. This association was stronger for, respectively, p-xylene, o-xylene, ethylbenzene, benzene, m-xylene and toluene
Multiple air pollutants exposure and leukaemia incidence in Tehran, Iran from 2010 to 2016: a retrospective cohort study
OBJECTIVE: Leukaemia is one of the most common cancers and may be associated with exposure to environmental carcinogens, especially outdoor air pollutants. The objective of this study was to investigate the association of ambient air pollution and leukaemia in Tehran, Iran. DESIGN: In this retrospective cohort study, data about the residential district of leukaemia cases diagnosed from 2010 to 2016 were inquired from the Ministry of Health cancer database. Data from a previous study were used to determine long-term average exposure to different air pollutants in 22 districts of Tehran. Latent profile analysis (LPA) was used to classify pollutants in two exposure profiles. The association between air pollutants and leukaemia incidence was analysed by negative binomial regression. SETTING: Twenty-two districts of Tehran megacity. PARTICIPANTS: Patients with leukaemia. OUTCOME MEASURES: The outcome variables were incidence rate ratios (IRR) of acute myeloid and lymphoid leukaemia across the districts of Tehran. RESULTS: The districts with higher concentrations for all pollutants were near the city centre. The IRR was positive but non-significant for most of the air pollutants. However, annual mean NOx was directly and significantly associated with total leukaemia incidence in the fully adjusted model (IRR (95% CI): 1.03 (1.003 to 1.06) per 10 ppb increase). Based on LPA, districts with a higher multiple air-pollutants profile were also associated with higher leukaemia incidence (IRR (95% CI): 1.003 (0.99 to 1.007) per 1 ppb increase). CONCLUSIONS: Our study shows that districts with higher air pollution (nitrogen oxides and multipollutants) have higher incidence rates of leukaemia in Tehran, Iran. This study warrants conducting further research with individual human data and better control of confounding
Efficiency of multi walled carbon nanotubes for removing Direct Blue 71 from aqueous solutions
Dye wastewater produced from industrial activity is usually toxic, resistant to biodegradation and persistent in the environment. The aim of this study was to evaluate the efficiency of multiwalled carbon nanotubes (MWCNTs) for decolorization of Direct Blue 71 (DB71). In this experimental study, the effect of various variables including contact time, solution pH, adsorbent dose, and initial dye concentration was evaluated in a batch reactor. The adsorption and kinetic models were evaluated to explain the adsorbed dye and dynamic reaction. The results of this study showed that the efficiency of dye removal increased, as the contact time and adsorbent dose increased, but as pH and initial dye concentration increased, removal efficiency decreased. The maximum efficiency of Direct Blue 71 removal was observed at acidic solution (pH=3), contact time of 90 minutes, adsorbent dose of 0.6 g/l and initial dye concentration of 25 mg/l. The adsorption of direct blue 71 best fitted the Langmuir isotherm (R2=0.87) and pseudo first order kinetic equation (R2=0.99). According to the results obtained, multiwalled nanotubes was offered as an effective adsorbent for removing direct blue 71. © Authors
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