Predictors of Preventive Behaviors of Cardiovascular Diseases: Based on Health Belief Model in Women Referred to Health Treatment Centers in Qom City, 2014, Iran

Background and Objectives: Cardiovascular diseases are one of the major cause of death in women and men worldwide, while these disease are largely preventable if necessary measures are taken. The present study aimed to determine the predictors of preventive behaviors of cardiovascular disease, based on Health Belief Model in women referred to health treatment centers in Qom city. Methods: This descriptive cross-sectional study was performed on 204 women referred to health treatment centers of Qom city in 2014. Sampling was done by cluster sampling method, and data were collected using Health Belief Model-based questionnaire. Data analysis was crried out using statistical tests, including Pearson&rsquo;s correlation, one-way ANOVA, independent T, and linear regression. The significance level was considered as p<0.05. Results: In This study, among the Health Belief Model constructs, perceived susceptibility (p=0.005), perceived severity (p=0.042), and self-efficacy (p=0.003), 20% of variance of preventive behaviors of cardiovascular disease was predicted in women referred to health treatment centers in Qom city. Conclusion: According to the results of the present study, in order to design preventive programs for cardiovascular diseases, considering the perceptions, such as perceived susceptibility, perceived severity, and self-efficacy, increase the likelihood of interventions&rsquo; success

UKM2 Chlorella sp. strain electricity performance as bio-anode under different light wavelength in a biophotovoltaic cell

A biophotovoltaic cell (BPV) is an electrobiochemical system that utilises a photosynthetic microorganism for instance is algae to trap sunlight energy and convert it into electricity. In this study, a local algae strain, UKM2 Chlorella sp. was grown in a BPV under different trophic conditions and light wavelengths. Once the acclimatisation phase succeeded, and biofilm formed, power generation by UKM2 algae at the autotrophic mode in synthetic Bold’s Basal media (BBM) under white, blue and red lights were tested. Polarisation and power curves were generated at these different conditions to study the bioelectrochemical performance of the system. Later, the condition switched to algal mixotrophic nutritional mode, with palm oil mill effluent (POME) as substrate. Maximum power generation obtained when using UKM2 in BBM under red light where a power density of 1.19 ± 0.16 W/m3 was obtained at 25.74 ± 3.89 A/m3 current density, while the open circuit voltage OCV reached 226.08 ± 8.71 mV. UKM2 in POME under blue light recorded maximum power density of 0.85 ± 0.18 W/m3 at current density of 16.75 ± 3.54 A/m3 , while the OCV reached 214.05 ± 23.82 mV. Chemical oxygen demand (COD) removal reached an efficiency of 35.93%, indicating the ability of wastewater treatment and electricity generation in BPV at the same tim

Mass transfer limitation in different anode electrode surface areas on the performance of dual chamber Microbial Fuel Cell.

In this study, the effect of different electrode surface areas on the performance of dual chamber Microbial Fuel Cells (MFC) was investigated. Four different electrodes with 12, 16, 20 and 24 cm2 surface areas were tested in an MFC system. The 20 cm2 electrode generated an output power of 76.5 mW/m2 was found to be the highest among all the electrodes tested. This might be due to better interactions with microorganism and less mass transfer limitation. In addition, this indicates that the chances for attachment of bacteria and generation of electricity in larger electrode surface areas might be limited by mass transport and by higher surface area. The output power generation was then followed by the 16, 12 and 24 cm2 electrodes which generated 69.6, 64.7 and 61.25 mW/m2 electricity, respectively

Metal Cation and Surfactant-Assisted Flocculation for Enhanced Dewatering of Anaerobically Digested Sludge

Flocculation and dewatering of anaerobically digested sludge is known to be a major cost factor in the economy of wastewater treatment plants. Hence, several endeavors have been underway in search of affordable and effective alternatives. This study focuses on the effects of different metal cations, including FeCl3, CaCl2 and MgSO4, on the dewaterability of digested sludge. The effects of these metal flocculants were also investigated in the presence of co-polymers and surfactants, which can be considered the novelty of this study. The polymers and surfactants investigated in this study were emulsion polymer, CTAB and SDS. Sampling and characterization of digested sludge was conducted, and total solid (TS), volatile solid (VS), dewaterability in capillary suction time (CST), total dissolved solids (TDS), chemical oxygen demand (COD), pH and conductivity of the unconditioned digested sludge samples were determined. The dewaterability of FeCl3, CaCl2 and MgSO4 conditioned digested sludge samples were compared, and MgSO4 conditioned digested sludge showed better dewaterability compared to the other two metal conditioning agents at a pH of 6.8. The dewaterability was further improved by the addition of emulsion polymer (EMA 8854), cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulfate (SDS). Fe Cl3 was found to perform better under an acidic pH of around 3. The dual conditioning using polymer and CTAB resulted in better dewaterability, with CaCl2 as metal conditioning agent. Moreover, the effects of pH, metal dose and polymer dose on the dewaterability of digested sludge were also investigated. The effects of metal and polymer conditioning on the particle size of the sludge flocs was also investigated. Optimum dewatering performance was achieved for metal doses of 0.16 v/v, 0.075 v/v and 0.16 v/v for FeCl3, CaCl2 and MgSO4, respectively, and a corresponding CTAB dose of 0.1 v/v and EMA dose of 15 kg/TDS were found to be the optimum. SDS as a polymer conditioning agent resulted in the deterioration of dewatering performance

Simultaneous organics, sulphate and salt removal in a microbial desalination cell with an insight into microbial communities

Microbial desalination cells (MDCs) are known among the bioelectrochemical systems for their green and cost-effective application in salt removal. However, the low efficiency of desalination compared to other chemical and membrane-based methods still holding this technology in laboratory and requiring further research and development (R&D) to establish actual plants. This study focused on integrating different applicable functions in one setup to promote applying MDCs in actual scale. In this research, the behavior of the MDC upon applying different salt concentrations in the desalination chamber was studied. Moreover, salt, sulphate and organic matter removal in acetate and sulphate-fed MDCs (A.MDC and S.MDC) were investigated. 10, 20 and 35 g/l of salt were successfully removed by using MDC technology. Sulphate removal of 72% was achieved within the S.MDC setup while similar current productions were observed in both A.MDC and S.MDC. Higher COD removal (88%) was recorded in S.MDC compared to 65% in A.MDC. Furthermore, the microbial communities were characterized and Rubrivivax was identified as the dominant genus in A.MDC while Desulfobulbus, Geobacter and Desulfovibrio were the most abundant genera in S.MDC setup

Effect of External load and Salt Concentration on the Performance of Microbial Desalination Cell

Microbial desalination cell (MDC) is one of the cost and energy-effective methods that can help people in countries with low income and the people in rural areas without energy infrastructure, get access to desalinated water while treating their wastewater. Despite the advantages of the technology, less is known about the behavior of the internal resistance in MDCs. Therefore, this study mainly focused on the behavior of MDC from the internal and external resistance points of view. The desalination rate of saltwater at different applied external resistance was studied. Moreover, the polarization capacity of the established MDC was investigated. The internal resistance of MDC at different salt concentrations of the desalination chamber was also analyzed and discussed. The findings of the study showed that decreasing the external resistance could increase the current generation of the MDC as the main driving force of desalination. Moreover, it was found that salt concentration in the middle chamber plays a significant role in the internal resistance of MDC and hence on the desalination rate. The lower desalination rate at the lower salt concentration of the desalination chamber could be explained by the high internal resistance of the system. Therefore, integrating MDC with other suitable techniques, e.g., reverse osmosis (RO), for desalination of lower salt concentrations could overcome this challenge. MDC as a standalone desalination system at the current stage of technology might not be practical due to the low current performance of the system. However, it is worth considering it as a green and low-cost technology for the pretreatment stage of the other conventional desalination systems like RO with energy and cost savings while treating the wastewater

Effect of External load and Salt Concentration on the Performance of Microbial Desalination Cell

Microbial desalination cell (MDC) is one of the cost and energy-effective methods that can help people in countries with low income and the people in rural areas without energy infrastructure, get access to desalinated water while treating their wastewater. Despite the advantages of the technology, less is known about the behavior of the internal resistance in MDCs. Therefore, this study mainly focused on the behavior of MDC from the internal and external resistance points of view. The desalination rate of saltwater at different applied external resistance was studied. Moreover, the polarization capacity of the established MDC was investigated. The internal resistance of MDC at different salt concentrations of the desalination chamber was also analyzed and discussed. The findings of the study showed that decreasing the external resistance could increase the current generation of the MDC as the main driving force of desalination. Moreover, it was found that salt concentration in the middle chamber plays a significant role in the internal resistance of MDC and hence on the desalination rate. The lower desalination rate at the lower salt concentration of the desalination chamber could be explained by the high internal resistance of the system. Therefore, integrating MDC with other suitable techniques, e.g., reverse osmosis (RO), for desalination of lower salt concentrations could overcome this challenge. MDC as a standalone desalination system at the current stage of technology might not be practical due to the low current performance of the system. However, it is worth considering it as a green and low-cost technology for the pretreatment stage of the other conventional desalination systems like RO with energy and cost savings while treating the wastewater