48 research outputs found

    AC-RDVT: Acyclic Resource Distance Vector Routing Tables for Dynamic Grid Resource Discovery

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    Since the objective of grid is sharing the numerous and heterogeneous resources, resource discovery is a challenging issue. Recently appeared, Ontosum, is a resource discovery method based on semantically linked organizations and a routing algorithm Resource Distance Vector (RDV), has been presented to forward resource discovery queries into the clusters. Although this framework is efficient for large-scale grids and nodes are clustered automatically based on semantic attributes to constitute a semantically linked overlay network, but the dynamic behavior of grid isn’t considered. In this method, deceptive information is stored in RDV tables (RDVT) which cause some problems in routing process. In this paper, a method is proposed to improve the dynamism of RDV routing algorithm, so the consistency with grid environments is increased. The developed algorithm is assessed by investigating the success probability, number of hops and routing time of resource discovery.DOI:http://dx.doi.org/10.11591/ijece.v3i1.183

    Comparative Investigation of Health Quality of Air in Tehran, Isfahan and Shiraz Metropolises in 2011-2012

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    Background and Aims: Air pollution causes wide spectrum acute and chronic effects of health from slight physiological disorders to death from cardiovascular and respiratory diseases. In order to set the control programs, air pollution monitoring and determination of air quality are necessary. The objective of this study was to compare health quality of air in Tehran, Isfahan and Shiraz cities in 2011- 2012.Materials and Methods: This Study was a descriptive–analytic study. The moment concentrations of Tehran,Isfahan and Shiraz air pollutants were gathered through referring to the environmental protection agency.Then, Air Quality Index (AQI) was calculated based on the criteria pollutants’ levels (CO, NO2, SO2, PM10,PM2.5 and O3) for three cities through linear interpolation and was classified into describing classes accordingto tables of National Ambient Air Quality Standards. Data analysis was performed with Excel and SPSS software using One-Way ANOVA test.Results: The results showed that the AQI in Tehran, Isfahan and Shiraz was higher than Iran’s environmental protection agency standards (AQI>100) in 341, 323 and 85 days, respectively. Furthermore, particulate matter (PM10) has been the critical pollutant in three cities for most days of the year. One-Way ANOVA test between AQI mean of the three cities showed a significant difference.Conclusion: The air quality of the three cities was unhealthy in 2011-2012 and the situation of Tehran andIsfahan air, however, was in the “bad situation”.Key words: Air pollutants, Air quality index, Pollution standard index, Responsible pollutan

    Evaluation of cardiovascular and respiratory mortality attributed to atmospheric SO2 and CO using AirQ model

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    Background: Air pollutants have multiple adverse effects on human health. In this study, the health effects of exposure to carbon monoxide (CO) and SO2 in the air of 6 Iranian metropolises in 2011-2012 were examined. Methods: Raw data was collected from the Iranian Department of Environment and the Iran Meteorological Organization. After validation, the required statistical indices were calculated through programming and modifying temperature and pressure in Excel software. The output of Excel was given to the AirQ model, and the results were presented as the cases of death. Results: The annual mean concentrations of SO2 were 2.45, 1.55, 0.6, 0.55, 1.05, and 3.8 times higher than the guidelines of the World Health Organization (WHO) (20 μg/m3) in Tehran, Mashhad, Isfahan, Shiraz, Tabriz, and Urmia, respectively. The concentrations of CO did not exceed the standard limit in any of the studied cities. The cumulative numbers of total deaths attributed to SO2 were 744, 122, 132, 44, 37, and 107 in Tehran, Mashhad, Isfahan, Shiraz, Tabriz, and Urmia, respectively. The highest mortality rate was found in Urmia at 2.9% followed by Tehran at 1.52%; the lowest rate of 0.46% was found in Tabriz. Conclusion: The results show that of the 6 metropolises, the highest CO mortality rate of about 2.15% belonged to Isfahan followed by Arak with about 1.38%, and the lowest rate of 0.68% belonged to Mashhad. Because of the growing trend of air pollution and its mortality rate and adverse effects, practical solutions for the control and reduction of air pollution in Iranian metropolises are necessary

    Comparison of the Effects of Visual and Auditory Distractions on Fistula Cannulation Pain among Older Patients Undergoing Hemodialysis: A Randomized Controlled Clinical Trial

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    Pain associated with fistula cannulation is a challenge for nurses who provide care to older patients undergoing hemodialysis. Several non-pharmacological methods have been suggested for relieving fistula cannulation pain, but the benefits of visual and auditory distraction methods among older patients undergoing hemodialysis have not been investigated yet. Therefore, this study aimed to compare the effects of visual and auditory distractions on fistula cannulation pain among older patients undergoing hemodialysis. This randomized controlled clinical trial was conducted on 120 older patients undergoing hemodialysis. They were randomly assigned to three groups of visual distraction, auditory distraction, and the control (n = 40 in each group) using a simple random assignment method. The distraction interventions continued for three consecutive sessions and the numeric rating scale of pain severity was used for data collection. Descriptive and inferential statistics were used for data analysis using SPSS. It was found that pain severity significantly reduced after the distraction interventions in either the auditory or visual distraction groups and also after all three distraction sessions (p = 0.001). However, visual distraction had a better effect on the reduction of pain severity. Therefore, while both visual and auditory distractions reduced pain severity in older patients undergoing hemodialysis, visual distraction was more effective. Nurses are encouraged to incorporate visual distraction as a safe and non-pharmacologic technique into routine nursing care for reducing older patients’ suffering and improving their wellbeing when fistula cannulation is performed

    Removal of Cephalexin From Aqueous Solutions Using Magnesium Oxide/Granular Activated Carbon Hybrid Photocatalytic Process

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    In the present study, magnesium oxide/granular activated carbon (MgO/GAC) composite as a catalyst was synthesized using the sol-gel method and its catalytic potential was investigated in the presence of ultraviolet (UV) irradiation for the removal of cephalexin (CLX) in a batch mode reactor. Then, the characterization of the MgO/GAC composite was determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Next, the effect of operational parameters was evaluated, including the pH of the solution (3-11), the dosage of composite (1-6 g/L), initial CLX concentration (20-100 mg/L), and contact time (10-60 minutes). The maximum CLX degradation with an initial concentration of 20 mg/L was as high as 98% at pH=3, 4 g/L of MgO/GAC composite with UV irradiation within 60-minute contact time. In addition, the removal process of CLX could be described by the pseudofirst-order kinetic. Further, the chemical oxygen demand (COD) and total organic carbon (TOC) removal rate were 78% and, 62.3% in optimum conditions, respectively. The results indicated that the UV/MgO/GAC hybrid photocatalytic process can be considered as an efficient alternative for treating the wastewater containing CLX

    Experimentally measured thermal masses of adsorption heat exchangers

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    The thermal masses of components influence the performance of many adsorption heat pump systems. However, typically when experimental adsorption systems are reported, data on thermal mass are missing or incomplete. This work provides original measurements of the thermal masses for experimental sorption heat exchanger hardware. Much of this hardware was previously reported in the literature, but without detailed thermal mass data. The data reported in this work are the first values reported in the literature to thoroughly account for all thermal masses, including heat transfer fluid. The impact of thermal mass on system performance is also discussed, with detailed calculation left for future work. The degree to which heat transfer fluid contributes to overall effective thermal mass is also discussed, with detailed calculation left for future work. This work provides a framework for future reporting of experimental thermal masses. The utilization of this framework will enrich the data available for model validation and provide a more thorough accounting of adsorption heat pumps

    The Safety and Effectiveness of a Polysaccharide Extracted from Rosa Canina in Patients with NAFLD: A Randomized Trial

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    Objective: Non-alcoholic fatty liver (NAFL) is a common pathology of hepatocytes due to the accumulation of fat which is predominantly implicated in obesity. Due to the multifaceted characterization of fatty liver and no effective treatment, this study was aimed to assess the protective effect of a polysaccharide in NAFL patients. Materials and methods: Polysaccharide fraction was isolated from Rosa canina and administered to 33 NAFL patients for 90 days. Demographic information, liver ultrasonography, and the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) enzymes were studied. Data were analyzed with the use of SPSS version 21 (SPSS, Inc.) All data were shown as means ± SDs and p < 0.05 was considered as significant. Results: After 90-day prescription, the weight loss, reduced activity of ALT and AST as well as changing the echogenicity of the liver from grades of 3, 2, and 1 to 2, 1 and normal, respectively, were observed in patients compared to the baseline (p ≤ 0.05). In addition, there were no visible side effects in patients during drug consumption. Conclusions: The data indicated that polysaccharide fraction with no obvious side effects is significantly able to protect the liver from steatosis in patients with NAFL disease. However, further information is required to better conclude on the effectiveness of the isolated polysaccharide as a promising fatty liver drug

    Investigating the Relationship Between High Levels of Angiotensin II in Plasma and the Rate of Deterioration in Hypertensive Patients to COVID-19

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    Introduction: The COVID-19 crisis poses a heightened risk to vulnerable populations. Considering factors influencing deterioration, complications, and mortality, it is especially important to pay attention to these groups, including persons with hypertension (HTN) and diabetes. This study aimed to investigate the correlation between the angiotensin II (ANG II) level and the disease severity and clinical course in COVID-19 patients. Methods: A cross-sectional study was conducted on 50 COVID-19 patients (mean age 59.1±20) admitted to Sinai hospital in Hamedan. The blood samples of the patients were taken during hospitalization and discharge, and the plasma ANG II level was measured using an enzyme-linked immunosorbent assay kit. The quantitative comparison was analyzed with paired t test and qualitative comparison with the chi-square test. The correlation of variables was checked with the Pearson test, and P<0.05 was considered statistically significant. Results: Overall, 44%, 16%, and 10% of COVID-19 patients had HTN, cardiovascular disease (CVD), and 10% diabetes, respectively. The oxygen level of 82% of the patients was below 90, of which 68% were intubated, and the lowest oxygen levels were observed in patients with HTN and CVD with 2 deaths. The primary and secondary examination of the ANG II level demonstrated that its level was significantly higher during illness compared to full recovery and decreased during recovery. Conclusion: The ANG II level is related to the severity of the disease in the early stages of 2019- nCoV infection. Therefore, HTN or other diseases that affect the level of ANG II in the blood can increase the severity of the disease

    Estimation of Short-term Mortality and Morbidity Attributed to Fine Particulate Matter in the Ambient Air of Eight Iranian Cities

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    Amongst the various pollutants in the air, particulate matters (PM) have significant adverse effects on human health. The current research is based on existing epidemiological literature for quantitative estimation of the current health impacts related to particulate matters in some selected principal Iranian megacities. In order to find the influence of air pollution on human health, we used the AirQ software tool presented by the World Health Organization (WHO) European Centre for Environment and Health (ECEH), Bilthoven Division. The adverse health outcomes used in the study consist of mortality (all causes excluding accidental causes), due to cardiovascular (CVD) and respiratory (RES) diseases, and morbidity (hospital admissions for CVD and RES causes). For this purpose, hourly PM10 data were taken from the monitoring stations in eight study cities during 2011 and 2012. Results showed annual average concentrations of PM10 and PM2.5 in all megacities exceeded national and international air quality standards and even reached levels nearly ten times higher than WHO guidelines in some cities. Considering the short-term effects, PM2.5 had the maximum effects on the health of the 19,048,000 residents of the eight Iranian cities, causing total mortality of 5,670 out of 87,907 during a one-year time-period. Hence, reducing concentrations and controlling air pollution, particularly the presence of particles, is urgent in these metropolises

    Renal Function and Risk Factors of Moderate to Severe Chronic Kidney Disease in Golestan Province, Northeast of Iran

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    Introduction: The incidence of end-stage renal disease is increasing worldwide. Earlier studies reported high prevalence rates of obesity and hypertension, two major risk factors of chronic kidney disease (CKD), in Golestan Province, Iran. We aimed to investigate prevalence of moderate to severe CKD and its risk factors in the region. Methods: Questionnaire data and blood samples were collected from 3591 participants (≥18 years old) from the general population. Based on serum creatinine levels, glomerular filtration rate (GFR) was estimated. Results: High body mass index (BMI) was common: 35.0 of participants were overweight (BMI 25-29.9) and 24.5 were obese (BMI ≥30). Prevalence of CKD stages 3 to 5 (CKD-S3-5), i.e., GFR &lt;60 mL/min/1.73 m2, was 4.6. The odds ratio (OR) and 95 confidence interval (95 CI) for the risk of CKD-S3-5 associated with every year increase in age was 1.13 (1.11- 1.15). Men were at lower risk of CKD-S3-5 than women (OR = 0.28; 95 CI 0.18-0.45). Obesity (OR = 1.78; 95 CI 1.04-3.05) and self-reported diabetes (OR = 1.70; 95 CI 1.00-2.86), hypertension (OR = 3.16; 95 CI 2.02-4.95), ischemic heart disease (OR = 2.73; 95 CI 1.55-4.81), and myocardial infarction (OR = 2.69; 95 CI 1.14-6.32) were associated with increased risk of CKD-S3-5 in the models adjusted for age and sex. The association persisted for self-reported hypertension even after adjustments for BMI and history of diabetes (OR = 2.85; 95 CI 1.77-4.59). Conclusion: A considerable proportion of inhabitants in Golestan have CKD-S3-5. Screening of individuals with major risk factors of CKD, in order to early detection and treatment of impaired renal function, may be plausible. Further studies on optimal risk prediction of future end-stage renal disease and effectiveness of any screening program are warranted. © 2010 Najafi et al
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