A land covers classification system for environment assessment in semi-arid regions of Iran

Land degradation is a major danger which restricting different areas of Iran. Systematic description of the environmentfor detection of environmental changes and the human-related causes and responses is essential in land cover changestudy. Use of land cover data allow detection of where certain changes occur, what type of change, as well as how theland is changing. Existing systems for classification of land cover is limited in the storage of the number of classes and isoften internally inconsistent. Therefore, Food and Agriculture Organization of the United Nations (FAO), developed theland cover classification system (LCCS), a comprehensive parametric classification based upon systematic description ofclasses using a set of independent quantifiable diagnostic criteria. With this approach land cover change detectionbecomes possible at the level of conversion of a class, whereas modification within a certain class type becomesimmediately identifiable by a difference in classifier, or through the use of additional classifiers as is shown in a series ofexamples illustrating the application of the approach to primarily vegetated areas. Our study showed this approach ismatch with exist information and dates for land cover mapping in Iran

Effects of vitamin e and zinc supplementation on antioxidants in beta thalassemia major patients

Objective: In beta thalassemic patients, tissue damage occurs due to oxidative stress and it happens because of the accumulation of iron in the body. This study was conducted to determine the effect of zinc and vitamin E supplementation on antioxidant status in beta-thalassemic major patients. Methods: This double blind randomized clinical trial was carried out on 120 beta thalassemic patients older than 18 years. Patients were randomly categorized in four groups. Zinc (50mg/day) and vitamin E (400mg/day) supplements were administered for former and latter group, respectively. In the third group both supplements were administered in similar doses. The fourth (control) group received no supplement. The effect of supplementations on serum zinc and vitamin E, superoxide dismutase (SOD), glutathione peroxidase (GPX), total antioxidant capacity (TAC) and body mass index (BMI) were measured at the beginning and the end of the study. Findings: Serum zinc levels in group 1 and 3 were significantly increased (P<0.007 and P<0.005, respectively). Serum vitamin E levels in group 2 and 3 were also increased significantly (P<0.001). Mean GPX activity in group1, 2 and 3 decreased significantly (P<0.015, P<0.032 and P<0.029, respectively). Mean SOD activity and TAC did not show significant change after supplementation. BMI had significant increase in all treated groups (P<0.001). Conclusion: Our results suggest that beta thalassemic patients have enhanced oxidative stress and administration of selective antioxidants may preclude oxidative damage. © 2011 by Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, All rights reserved

A Novel Cooperative Distributed Secondary Controller for VSI and PQ Inverters of AC Microgrids

This paper proposes a novel cooperative secondary control strategy for microgrids which is fully distributed. There is a two-layered coordination, which exists between inverter based DGs of both types, i.e. Voltage Source Inverter (VSI) and Current Source Inverter (CSI), also called PQ inverter. In first layer of the proposed two-layered cooperative control strategy, VSIs will take care of the primary average voltage regulation by implementing the average consensus algorithm (ACA); then in the second layer of control, the PQ inverters will improve the voltage quality of the microgrid while maintaining the average voltage of buses at the same desired level. Zone dedication algorithm is utilized in the second layer for voltage quality purposes based on sensitivity analysis. The sensitivity analysis is based on Simplified Jacobian matrix and the result of that is used to define the zone related to each DG in the microgrid. The goal of this zone dedication is to assign loads to the DGs that can compensate their changes with less effort (generating less power) than the others. There are two major contributions in this paper; 1- PQ inverters are effectively involved to increase microgrids capacity for better power management by introducing sensitivity to the PQ inverters set-point. This is defined based on the structure of the microgrid and takes into account the location of load changes. 2- The proposed strategy not only focuses on transient response but also improves the steady state response which smooths the voltage profile of the system while keeping the average voltage at the same desired level. The algorithm has been applied to a 13 bus system with a fully distributed communication in which each VSI inverter only communicates with its immediate neighbors and each PQ inverter is only in touch with associated bordering agents. The conclusive results verify that the proposed control strategy is an effective way to control the microgrid\u27s voltage to have a smoother and stable voltage profile. The analysis also confirms the robustness of the proposed cooperative control in presence of possible time delays

Comparison of knowledge, attitude and practice of Urban and rural households toward iron deficiency anemia in three provinces of Iran

Background: Lack of nutritional knowledge is one of the most important reasons of nutritional problems and consequently improper practice, which can lead to several complications. This study has been designed in order to compare knowledge, attitude and practices of the urban and rural households regarding iron deficiency anemia (IDA) in Boushehr, Golestan and Sistan & Balouchestan provinces in 2004. Methods: The sampling method at household's level in each province was the single-stage cluster sampling with equal size clusters. The necessary data were gathered with a structured questionnaire and via the interviews between the questioners and the eligible people in each household. Comparison of frequency of variables between urban and rural areas were tested by chi square test. Results: A total of 2306 households were selected as overall sample size. In urban areas, people recognized iron food sources better than rural areas. Knowledge level of respondents about vulnerable group for IDA and the favorite attitude of households toward IDA were better in urban areas of Sistan & Blouchestan and Golestan provinces. In Sistan & Balouchestan and Golestan, rural households who drank tea immediately before or after meal was more than urban ones. The majority of pregnant and lactating mothers (except for rural areas of Bushehr) did not take iron supplement regularly. Less than 60 percent of children used iron drop regularly. Conclusion: Knowledge, attitude, and practice levels of households toward IDA were not acceptable. One of the best ways of improving nutritional practice is nutritional education with focus on applying available food resources

A suggested prototype for assessing bone health

Background- Osteoporosis is becoming a health concern worldwide. Considering the fact that prevention plays an important role in reducing the burden of this silent disease and in view of the limited resources available, many countries have adopted certain programs to fight osteoporosis through shifting their attention towards at-risk individuals. The Iranian Multicenter Osteoporosis Study (IMOS) is one of these programs. The program aims to assess bone health and the prevalence of vitamin D deficiency in different parts of Iran with various altitudes, latitudes and lifestyle habits in a way that the results could be generalized to the country. Method- The present article presents the protocol used in the third phase of the study. It was designed based on the experiences gathered in the previous phases to overcome the shortcomings particularly subject loss. The questionnaire applied in this study was developed based on a thorough literature review of the risk factors and secondary causes of osteoporosis and was approved by an expert panel. It should be added that while the majority of the existing studies aim to study a certain aspect of osteoporosis, the present protocol provides the information needed for policy makers and researchers to study different osteoporosis-related issues. Conclusion- The authors believe the protocol, to be implemented with small modifications, can help policymakers in different parts of the world, particularly developing countries, gather accurate information on different aspects of bone health at the national level. © 2015, Academy of Medical Sciences of I.R. Iran. All rights reserved

Hepatitis B/C virus co-infection in Iran: A seroepidemiological study

Background/aims: As hepatitis B and C virus have the same transmission routes, dual infection may occur. The aim of this study was to determine the seroprevalence of HCV in HBsAg-positive subjects. Methods: 139 HBsAg-positive subjects were enrolled in the study. Serum samples were tested using ELISA method for anti-HCV antibodies. Chi-square and Fisher's exact tests were used to compare the proportions. Results: There were 68 (48.9%) males and 71 (51.1%) females. The mean age was 41.89±11.30 years. One case was excluded because of inadequate blood sampling. Anti-HCV antibody was positive in 17 (12.3%) of the 138 remaining subjects. Seropositivity of HCV was similar between female and male patients (p=0.69). Conclusion: The seroprevalence of co-infection with hepatitis B virus and hepatitis C virus in our study was higher than such reports from some countries (Italy), but was in line with worldwide prevalence (>10%)

Characteristics of high-risk sexual behaviors for human immunodeficiency virus infection among Iranian drug abusers

Objectives: This study was conducted to estimate the prevalence and the associated factors of high-risk sexual behaviors among drug abusers referred to a methadone clinic in Gorgan, the capital of Golestan province in the northeast of Iran, to help health care decision makers on designing interventional programs. Methods: In this cross-sectional study, 400 drug abusers referred to our methadone clinic were evaluated for high-risk sexual behavior. A logistic regression model was fitted for the association between independent variables and high-risk sexual behavior. Results: Approximately a quarter of patients (25.5%) had high-risk sexual behavior among which 47% had not used a condom in their last sexual contact. Drug abusers who had poor economic status had a lower chance of high-risk sexual behavior than those with good economic status (adjusted odds ratio [AOR] = 0.35, 95% confidence interval [CI] = 0.13-0.96). Also, 1-year increase in age reduced the chance by 6% (AOR = 0.94, 95% CI = 0.91-0.98). Heroin abusers, compared with opium abusers, had a duplicated chance of having high-risk sex (AOR = 2.11, 95% CI = 1.12-3.96). Conclusion: According to this study, high-risk sexual behavior in the drug abusers referred to methadone clinic was associated with younger age, good economic status, and heroin addiction. Hence, in interventional planning, more attention should be paid to young drug abusers, patients with good economic status, and heroin addicts as well. Copyright © 2012 American Society of Addiction Medicine

Serum leptin levels and irritable bowel syndrome: A new hypothesis

GOALS: This study was undertaken to investigate the relationship between serum leptin levels and the development irritable bowel syndrome (IBS). BACKGROUND: Stress has been known as an important causative factor in IBS. Various studies have indicated the relationship between serum leptin levels and stress levels. So searching the relationship between the production and level of this hormone and development of IBS may help to understand the pathophysiology of the disease. STUDY: This was a case-control study. Eighty IBS patient and 80 controls were recruited. All participants were asked to fill in a questionnaire included demographic information and medical history and also a stress questionnaire. Serum leptin level was measured by enzyme-linked immunosorbent assay method. Chi-square, Student t test, Pearson correlation and logistic regression were used for investigating the relationships between variables. RESULTS: Mean serum leptin levels were 7.41 and 19.33 ng/mL in IBS and control groups, respectively (P<0.001). Participants in IBS group had significantly higher stress levels than controls (P<0.001). Multivariate logistic regression analysis showed that adjusted odds ratios (ORs) for serum leptin level (OR: 0.9; 95% confidence interval: 0.85-0.94) and stress level (OR: 1.15; 95% confidence interval: 1.09-1.23) were nearly the same as crude ones. CONCLUSIONS: This study indicated the relationship between leptin and IBS for the first time. Our results show that serum leptin level is significantly lower in IBS group than controls and this relationship is independent of other variables such as stress levels, body mass index, etc. This may help in better understanding of the pathogenesis of IBS and consequently lead to the development of more effective treatments. © 2009 Lippincott Williams & Wilkins, Inc

Seed dormancy-breaking and germination requirements of

Dormancy breaking and germination requirements were investigated in seeds of Ferula ovina and Ferula gummosa. Seeds of rather species were collected from north and eastern-north rangelands of Iran. Seeds of each of the species were subjected to different treatments including various levels of GA3, chilling and combination of GA3 and chilling (GA-chilling). In contrast to treated seeds, non-treated seeds did not germinate. Germination of both species increased at higher concentration of GA3. In the case of Ferula ovina the highest germination percentage was obtained when the seeds were treated with 1000 ppm GA-chilling with 76% of germination. For Ferula gummosa seeds, the highest germination percentage was found when exposed to 1500 ppm GA-chilling with 53% germination. Both species well responded to different periods of cold stratification (30/60 days), especially F. ovina with 36% and 55% germination, respectively. The results suggest that F. gummosa has deeper dormancy. For both species, germination rate was positively correlated with germination percentage. Keywords: Chilling; Dormancy; Ferula ovina; Ferula gummosa; GA3; Germinatio