Journal of School of Public Health and

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Background and Aim: Domestic violence against women is a serious public health problem and women adopt different solutions to fight against it. This study was carried out to determine the prevalence of intimate partner violence and views of women
on adopting ways to fight against it in Arak city, Iran, year 2008.

Methods and Materials: In a cross-sectional study in Arak city in 2008, a total of 1037 women were interviewed. The data collected were analysed statistically.

Results: Findings showed that the common types of abuse were emotional (64.6%), verbal (57.1%), financial (32.3%), and physical (26.8%). The women mentioned that the most efficient ways they chose to counteract the abuses were as follows: resuming talking after the settlement of quarrels (93%), keeping silent on the part of one of the partners (81%), and seeking advice from the older members of the family (81%). The considered going into a temporary sulk (51%) and reciprocation (46%) ineffective methods. Correlations were found between violence on the one hand and education, job, addiction of the spouse, income of the spouse, mental disorder of the partner, and number of children on the other hand (p<0.05).

Conclusion: Results of this study show that a large number of women are subjected to different types of violence. It seems that increasing awareness of married women and girls concerning effective counteractive methods can be an effective step in solving this social problem.

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Background and Aim: Natural organic matter (NOMs), measured on the basis of organic carbon, produces disinfection by-products precursors (DBPs) during the chlorination process. Some DBPs are carcinogenic. NOMs are not completely removed by conventional water treatment. As a result, in addition to forming DBPs, they support bacterial regrowth in the water distribution systems and cause unpleasant odor and taste and other problems. The objective of this study was to determine organic carbon concentration and DBPs formation potential in drinking water of the water distribution system in Tehran, Iran.

Methods and Materials: Water sampling was done by standard methods, monthly between August 2006 and Feb 2007, at four points of the drinking water distribution system in Tehran. Quantitative parameters, including pH, EC, UV254 (UV absorbance at a wavelength of 254nm), dissolved organic carbon (DOC), and specific UV absorbance (SUVA) were determined. DOC and UV-254 of the samples were determined using a Total Organic Carbon (TOC) analyzer and a Lambda 25 UV/Vis spectrophotometer, respectively. SUVA (L/mg.m) was calculated as thea ratio of the UV absorbance at 254 nm (1/m) to DOC (mg/ L).

Results: The water content of DOC at the four points of the distribution system was less than 0.7 mg /L. The mean DOC concentration was 0.3±0.14mg/L, ranging between 0.12 and 0.687mg/L, with no monthly variation. The mean SUVA was 1.3±0.7.

Conclusion: It can be concluded that the Tehran water treatment systems cannot eliminate completely natural organic matter. SUVA values show, however, that the system can eliminate the majority of hydrophobic compounds. Therefore, formation of haloacetic acids is more probable than that of trihalomathanes.

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Background and Aim: The large volume of reports and statistics in the literature on the prevalence of musculoskeletal disorders (MSDs) in Iran and other countries indicates that it is essential to assess the ergonomic situation in different occupations. These disorders can be caused by long-term exposure to different agents or by trauma to the musculoskeletal system. A large part of the work force in Iran is engaged in general construction and dam construction workshops. The postures of these workers while working in the workshops are unsuitable postures. The objective of this study was to assess the ergonomic situation of workers in dam construction workshops.

Methods and Materials: This was a cross-sectional study conducted in 2008. The sample included 110 randomly selected male-workers in a dam construction workshop in Takab City, Iran, engaged in 25 different jobs. Data were collected using the Nordic Musculoskeletal Questionnaire and the National Institute of Occupational Health-Center to Protect Worker Rights Checklist (NIOSH-CPWR), both developed by the National Institute of Occupational Health-Center to Protect Workers Rights. The software used to analyze data was SPSS.

Results:The average service record of the workers was 36.6 ± 86.8 months. The data show that the most common (55.5%) MSDs were in the low back region. There were statistically significant positive associations between prevalence of MSDs and many independent variables, namely, age, weight, education level, service record, smoking, type of job, lengths of time of standing and sitting at work, total duration of work, work pressure, undesirable postures, and surface for walking.

Conclusion: The results of this study generally confirm findings of previous investigators. It can be concluded that ergonomic assessment of jobs may give valuable information to be used by occupational health and safety authorities in planning preventive and educational programs.

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Background and Aim: The aims of this study was to explore the feasibility of improving efficiency of the wastewater treatment system of the Fars Pegah Dairy Industries (FPDI) and propose ways to upgrade it in 2006-2007. The FPDI wastewater treatment system was of a successive anaerobic-aerobic type using anaerobic stabilization ponds and conventional and extended aeration activated sludge. Due to improper design and operation, it did not meet the required standards with regard to disposal to the surrounding cultivated land.
Materials and Methods: To overcome the problem and eliminate the bad smell, modifications were made, such as changing the entries and exits of the ponds, adjustment of the activated sludge process, and converting the conventional activated sludge F/M to a step-feed activated sludge shift. The efficiency of the system was assessed before and after these modifications
Results: The efficiency of the system to eliminate biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total dissolved solids (TDS), total suspended solids (TSS), total coliform, and fecal coliform increased from 82.42%, 86.87%, 64.18%, 20.23%, 54.56% and 50.87% to 97.34%, 98.61%, 90.4%, 28.44%, 90.09% and 89.95%, respectively.
Conclusion: The findings show improvements in the efficiency of the wastewater treatment system due to the changes made in it. It was also observed that efficiencies of the feed-step aeration and the extended aeration are similar. This means that application of the extended aeration in the treatment system of the plant would result in waste of money and energy.

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Background and Aim: Despite the fact that the proportion of youth population is very high in Iran, there is no well designed, comprehensive reproductive health program for the youth. This prompted the health planners to evaluate all the existing centers that deliver reproductive health services to the youth in the country in order to identify the weaknesses and strengths of the services and the centers.

Materials and Methods: A descriptive analytic study was conducted from March 2006 to March 2007, in coordination with the Vice-chancellor for Health of Universities of Medical Sciences, through Offices for Health of the Youth and Schools (OHYS). Five health centers, namely, Tehran, Semnan, Bam, Chabahar, and Fassa Health Centers (the only centers delivering reproductive health services to the youth) were included in the study. They were assessed for structure and physical facilities, job satisfaction of the personnel, satisfaction of the youth consulting them, and the services (including consultative services) delivered. The data were gathered through questionnaires using a checklist and analyzed by the SPSS-13 software.

Results: The health center personnel thought that the quality of services delivered at the centers was low. They also believed that the physical facilities, including equipment in the clinical examination room, furniture, cleanliness of the premises, and entertainment facilities, were not of an acceptable standard. About 64% of the personnel of the health centers personnel expressed job satisfaction. On the other hand, 39% of the young people consulting the centers expressed full, and 54% relative, satisfaction with the services they were receiving the remaining 7% were not content at all. The highest rate of satisfaction was with the psychologist, physician, and midwife, so that 95% of the clients recommended the centers to other young people seeking reproductive health services. Finally, the clients said that in most of the centers paramedical personnel, including nutrition officers (50%) and midwives with a Master's degree (17.5%), were insufficient.

Conclusion: It is suggested that a comprehensive service package be developed to be used in all the health centers, rather than each center deliver services based on the existing facilities and individual preferences. Such a package should be based on the national reproductive health programs (according to the medical education curricula). Intersectoral collaboration (particularly from the Ministry of Education and cultural organizations) is also very essential.

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  Background and Aim: Human error often plays an important role in accident causation either through direct action or poor design . The focus of this work is was on prediction of human error probabilities during the process of emergency musters on in gas compressor stations . This paper aims to present a brief description of Human Error Probability Index (HEPI) for the on gas compressor station musters process.

  Materials and Methods : Due to a lack of human error databases, and in particular human error data on gas compressor station musters, an expert judgment technique, the Success Likelihood Index Methodology (SLIM), , was adopted as a means to predict human error probabilities Two muster scenarios of varying severity (gas release, fire and explosion) were studied in detail . A total of 34 reference graphs provided data for both the weighting and rating of six performance shaping factors and the data were subsequently processed by means of SLIM to calculate the probability of success for 16 muster actions ranging from point of muster initiator to the final actions in the temporary safe refuge (TSR). The actions were categorized into 4 phases, namely, awareness, evaluation, egress, and recovery phases. The six performance shaping factors considered in this work were stress, complexity , training, experience, event factors, and atmospheric factors .

  Results: Human error probabilities in the egress phase were highest, followed by those in the evaluation phase the lowest were in the awareness phase.

  Conclusion: The HEPI can be applied to limit the chances of human error occurrence and mitigate the consequences of such errors through changes in training, design, safety systems, and procedures, resulting in a more error-tolerant design and operation .

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Background and Aim: Today in many work environments, such as nuclear, military and chemical industries, human errors may result in disasters. Accidents in different parts of the world bear evidence to this examples are the Chernobyl disaster (1986), the Three Mile Island accident (1974), and the Flixborough explosion (1974). Thus, identification of human error, especially in complex and intricate systems, and devising control measures are essential.

Materials and Methods: This project was a case study conducted in Zagross Methanol Company in Asalouye (South Pars), Iran. The walking-talking-through method was used to collect the required data and complete the Systematic Human Error Reductive and Predictive Approach (SHERPA) worksheets. The process experts and control room operators were interviewed and technical documents of the Company examined.

Results: Analysis of the SHERPA worksheets indicated that the majority (48.62%) of the 222 errors identified were action errors, followed by checking errors (31.97%), retrieval errors (6.75%), selection errors (0.9%), and communication errors (11.7%).

Conclusion: The results of this study show that the method can be used effectively in different industries, especially chemical industries, to identify human errors that may potentially lead to dangerous situations and accidents.

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Background and Aim: Weight status perception is an important factor in nutritional behavior. The aim of this study was to determine Islamshahr women's self-perception of their obesity status and perception of their husbands' opinions regarding women's obesity status, as compared with the actual central obesity status of the women.

Materials and Methods: This was a cross-sectional (descriptive-analytical) study carried out in 2003 on a cluster sample of Islamshahr women aged 20-65 years (n = 704). Data were collected by interviews and weight, height, and waist and hip circumferences were measured. A waist-to-hip ratio (WHR) greater than 0.849 was considered as central obesity. Based on the body mass index [BMI=weight/height²(kg/m²)],  underweight,  normal, overweight, and obese were defined as a BMI <18.5,  18.5-24.9 ,  25-29.9, and  ≥30, respectively.

Results: About 35% of the women with central obesity considered themselves underweight or normal. Married women's perception of husbands' opinions regarding their  obesity status showed about 45% misclassification. Women with central obesity who thought their husbands would assess them as underweight or normal were more likely [OR=18.6, 95% CI: 9.1 to 38.2] to underestimate their obesity status as well.

Conclusion: Misperception of obesity status is common among Islamshahr women. Considering the role of central obesity in metabolic diseases, menstrual disorders and increasing serum androgens, conducting nutrition education programs is essential for prevention and control of central obesity in the region studied.

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Background and Aim: Multiple sclerosis (MS) is considered as a common inflammatory disease of the human central nervous system (CNS). 4 amino pyridine (4-AP), a potassium channel blocker, is used widely in MS treatment to reduce fatigue and cachexia often experienced by the patients. The objective of this study was to get a better understanding of the mechanism of action of this drug, using the cell culture model. More specifically, we attempted to determine the effects of the drug on 1. The profileration of, and its cytotoxicity on, the neurons, and 2. The activity of MMP-9 in the neurons.

Materials and Methods: Considering the available reports on the wide range of 4-AP effects, we designed this study to investigate its possible role in proliferation or cytotoxicity of the MS cellular model, i.e. astrocytoma U373-MG, using the MTT assay technique. We also analyzed the effect of 4-AP on cell functionality as assessed by matrix metalloproteinase-9 (MMP-9) zymography.

Results: The results showed that while 4-AP at a concentration of 0.1 and 1 mM has no significant cytotoxic effects on the treated cells, it has remarkable MMP-9 inhibitory effects (p<0.01). The proliferation analyses confirmed the stability of 4-AP effects on cell functionality.

Conclusion: On the whole, the results of the present study show the desirable effect of 4-AP on MMP-9 activity at non-cytotoxic doses, promising its further therapeutic applications.

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Background and Aim: Patients who consult hospital due to physical or mental damages have legal rights. Observation of patients' rights will result in patient satisfaction, which will help to improve hospital services. The aim of this study was to determine awareness and observation of patient's right in hospitals affiliated with medical universities in Tehran.

Materials and Methods: This was a cross-sectional study conducted in 2009 in hospitals affiliated with medical universities in Tehran. A total of 601 patients were randomly selected from 11 hospitals affiliated with three medical universities in Tehran. Data were collected using a 50-item questionnaire the validity and reliability of which had been confirmed. Chi-square and Kruskal-Wallis tests were used for statistical analysis. The software used was SPSS.17.

Results: The mean age of the patients (59% females and 41% males) was 43.3 (SD=18.5) years and the average length of hospitalization 7.1 (SD=7.4) days. Data analysis showed that the proportions of the patients with a poor, intermediate and desirable patients' rights awareness were 71.5%, 22.0% and 5.8%, respectively. Observation of patients' rights was good in 13.8% of the cases, medium in 82.9% of the cases and poor in 3.3% of the cases. There was a significant statistical relationship between observation of patients' rights on the one hand and the hospital ward and length of stay on the other hand (p=0/007). Further analysis of the data showed that the strongest and the weakest observed rights were patient awareness right and the right of making objections and lodging complaints, respectively.
Conclusion: The results of this study showed that patients are not well aware of patients' rights and that observation of patient's rights is not at a desirable level. We recommend organizing public educational programs including components on patients' rights and follow-up of patient' rights violations, as well as passing a comprehensive act to ensure observation of patients' rights and specific programs designed for monitoring and supervising it.

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Background and Aim: This study was undertaken to determine the effectiveness of a safe community program, as an international community-based program, for injury prevention and safety promotion, in Kashmar

Materials and Methods: In this retrospective study, the data on injured patients consulting hospital emergency wards in Kashmar and 44 other districts (as control) for a period of 3 years (March 20 2005 to March 19, 2008) were analyzed and compared.

Results: The number of injuries/100,000 population in Kashmar was 4654.6, 4570.9, and 4949.2 in March 2005-2006, 2006-2007, and 2007-2008, respectively. The corresponding figures (means) for the control districts were 822.7, 1130.0 and 1245.5. The injury- related fatality rate in the emergency ward for the 3 periods was 57.6, 52.9, and 44.2 per 100,000 in Kashmar and 12.2, 13, and 11.9 per 100,000 in the control districts. The injury rate showed an increase and the injury- related fatality rate showed a decrease in both Kashmar and the control districts over the 3 year period, but there was a statistically significant difference between the decreased injury-related fatality rate in Kashmar (p<0.0001).

Conclusion: The Kashmar International Safe Community Program resulted in no significant decrease in the rate of injuries in Kashmar. However, as compared to the control distrcts, it caused a decrease in the injury-related fatality rate over the 3-year period. Long-term studies are necessary to confirm these results.

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Background and Aim: Food insecurity implies a limited ability to secure adequate and safe food or limited or uncertain ability to acquire acceptable foods in socially acceptable ways. The nutrition transition in Iran is taking place in the context of rapid demographic change and urbanization in spite of underweight, obesity and overweight increased, especially among women. It is usually expected that food-insecure people have an inadequate food intake, less body fat, and body weight. However, several studies in developed countries have shown a higher prevalence of overweight/obesity among food-insecure household members, especially women. Under weight and overweight or obesity is the most common nutritional disorder in the developed countries and is assuming to become a serious health problem in developing countries. This study aimed to assess the association between food insecurity and socio-economic factors in households and body mass index among urban women in Dezful in 2008.

Materials and Methods: A total of 400 household were randomly selected by two stage sampling from different areas in Dezful. Heights and weights of all women were measured based on standard protocols, and body mass index (BMI) was calculated. BMI status was defined based on cut-off values recommended by NIH( under weight = BMI<18.5, normal weight 18.5< BMI< 25, overweight 25≤BMI<30 and obesity BMI≥30 Women provided detailed demographic and food insecurity information via a face- to- face interview. Information on food insecurity was collected using the instrument originally developed by USDA. All analysis was conducted using the SPSS statistical package.

Results: The prevalence of household food insecurity was %37.6 and 42.8% of the women were overweight, and 12% obese, respectively. Results showed that, BMI was positively associated with food insecurity, women's age and family size and inversely associated with , race and economic status (p <0.05).

Conclusion: It is evident that household food insecurity, overweight and obesity coexist in Dezful. Women age, family size, race and economic status were recognized as associated factors with food insecurity but other factors didn't show significant relationship. There is lack of published information regarding food insecurity and some factors affecting with body weight status therefore, it is necessary to perform such studies in other regions too.

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Background and Aim: Nowadays Clinical Skills Centers are important structural components of medical education systems globally. In these centers medical students are trained using a variety of methods and techniques, one method being teaching in structured stations. The objective of this study was to determine the efficacy of this method by comparing the students' self-assessment of their own basic surgical skills before and after structured stations teaching.

Materials and Methods: This quasi-experimental study was conducted in 2004-08 in Tehran University of Medical Sciences. The participants included 268 medical students at the clerkship stage there were 3 trainer groups. The pre- and post-self assessment techniques were used to assess the learning progress. ANOVA & Paired-t and non-parametric tests were used for data analysis.

Results: Irrespective of which year the students were in, self- scoring on 17 cognitive subjects and 10 procedural skills showed a significant improvement after the instruction (p<0.001). There were significant differences among the 3 trainer groups (p<0.001).
Conclusion: This study suggests that teaching basic surgical skills using structured stations is effective in improving practical skills.

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Background and Aim: The most common cancer in Iran is digestive system cancer, the highest incidence of which is reported from the Caspian Sea littoral. This study aimed to determine factors affecting the survival of patients with gastrointestinal cancer using the Cox and parametric models the 2 models were compared.

Materials and Methods: This survey was a prospective study conducted between 1990 and 1991. Data were collected through the Cancer Registry Center in Babol, which functions under supervision of the School of Public Health and Institute of Public Health Research, Tehran University of Medical Sciences. We tried to identify cases of gastrointestinal cancers. The individual characteristics of 484 patients, namely, age, sex, family history, marital status, smoking status, occupation, ethnicity, medication status, education, residence (urban, rural), and type of cancer were recorded. The patients were followed up for a period of 15 years, i.e., until 2006 year. To determine the effective factors on survival of patients, the Cox model and parametric models such as exponential, weibull, log-normal, log-logistic, and the AIC criteria and residuals were used to compare the effectiveness of the models. The SAS and STATA software were used for data analysis, with a significant level of 0.05.

Results: Sixty-six percent of the patients (total n=484) were males and 34% females, with a mean age of 59 and 55 years, respectively. Their distribution according to type of cancer was as follows: esophageal cancer, 359 (74.2%) stomach cancer, 110 (22.7%) colorectal cancer, 15(3.1%). Estimated one-, three-, and five-year survival rates were 24%, 16% and 15%, respectively.

Conclusion: The results of this study reveal that gender and family history can be strong risk factors for GI cancer. Log-normal and log-logistic models in multivariate and univariate analyses gave almost similar results. However, based on AIC criteria and residuals analysis, the log-logistic model gives the best fit as compared to other parametric models and can be used instead of the Cox model for determining factors affecting survival of patients with gastrointestinal tract cancer.

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Background and Aim: Pressure ulcer is a common problem and a large drain on hospital resources, especially in wards such as ICU where patients stay for a long time. The aim of this study was to explore the likely factors contributing to pressure ulcers in the ICU units of Tehran University of Medical Sciences teaching hospitals, Tehran, Iran.

Materials and Methods: This project was conducted in all the seven ICUs of four teaching hospitals affiliated to Tehran University of Medical Sciences. In the first phase the researcher performed a direct observation of all the 90 patients who were admitted to the ICU units to check the presence of any pressure ulcer. In the second phase, 310 patients discharged from the same ICU units between March 2007 and February 2008 was randomly selected and their medical records reviewed. A structured questionnaire was used to collect the data.

Results: Pressure ulcer occurred more frequently in the elderly women patients who were less active and had less mobility, hospitalized for a long time, or those with fever, diabetes, high blood pressure, paralysis, or respiratory diseases. In addition, pressure ulcer was seen more frequently in the patients hospitalized in the general ICUs, as well as in those with infections and different types of tumors.

Conclusion: Using a standard risk assessment tool and paying attention to the main risk factors of pressure ulcer can be a useful method for identifying the high-risk patients before admission in order to prevent them from developing such ulcers.

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Background and Aim: Lead is a toxic metal used in different industries and occupational and environmental exposure to it is quite likely to occur. Because of its high potential toxicity, serious damages to those exposed to it are common. Since the ceramic industry, in which lead is used, is considered a domestic industry in Iran, in this study occupational exposure of glaze workers to lead was assessed in a ceramic industry.

Materials and Methods: A total of 55 glaze workers (39 tillers and 16 potters) were selected as the case group. Association of lead concentration with several variables, including work shift, work type, ventilation system, and the number of extra work hours during the previous month, was determined. A sampling pump (SKC Co.) and ester cellulose filters with a pore size of 0.8 µm, 37 mm in diameter, were used for sampling. The flow-rate was adjusted at 2 l/min based on the NIOSH 7300 method. After sampling, filters were transferred to the laboratory and digested in a mixture of nitric acid and per chlorate solution (4:1) and analyzed by ICP-AES. To minimize probable errors and pollution during sampling and sample handling, samples were also taken from employees in the administration department to serve as control. Spiro metric tests were performed on both the case and the control groups.

Results: The lead concentrations were higher than the threshold limit value (TLV) (0.17 mg/m). Independent t-test showed that there was a significant relation between concentration of the lead present in the breathing zone air and 2 independent variables, including shifts work (morning and afternoon) and the ventilation system among tillers. Also, based on the one-way ANOVA, there was a significant relation between concentration of the lead present in the breathing zone and the number of extra working hours over the shift.

Conclusion: The mean lead concentration in the breathing zone was higher than the respective TLV. Considering the hazardous nature of lead, protective measures─ personal, occupational and environmental─ should be taken. Moreover, clinical examination of job applicants at the time of employment, as well as periodic examinations and Spiro metric tests on the workers, are also strongly recommended.

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Background and Aim: Rabies, a viral and zoonotic disease, causes acute and fetal encephalitis in humans and other mammals and is a cause of death in developing countries. It is usually transmitted by animal bite, but other routes of transmission are mucus membranes, breathing, placenta, contaminated instruments, and organ implanting. This study shows the mapping of geographical distribution of animal bite cases, rabies, and death due rabies in 3 Caspian Sea littoral provinces, namely, Golestan, Mazandaran, and Gilan.

Materials and Methods: Data on human and animal rabies cases and animal bites were collected from the Reference Rabies Center of the Pasteur Institute in Tehran and the Rabies Diagnosis Section of the Amol Research Center during 2002-2007.The data was analyzed by the SPSS (11.5) software and mapping was done by Arc GIS 9.2.

Results: During the 6-year period, of the 670,743 animal bite cases reported in Iran 63890 (9.5%) had occurred in Golestan, 25,767 (3.8%) in Mazandaran, and 22,874 (3.4%) in Gilan. The distribution of animal bite cases in the 3 provinces was as follows: Agh ghala, Bandar Torkaman, Azad shahr and Kolaleh in Golestan Galugah, Behshahr, Ramsar and Neka in Mazandaran and Shaft, Masal, Siahkal and Fuman in Gilan. The data also showed that of the total 2,312 animal rabies cases, in Iran, 9.22% had been reported from Golestan, 4% from Mazandaran, and 2.6% from Gilan. Furthermore, animal rabies cases had occurred mostly in Gonbadekavoos, Bandar Torkaman, Gorgan and Kolaleh in the Golestan Province Behshahr, Neka and Chalus in the Mazandaran Province and Masal, Fuman and Rezvanshahr in the Gilan Province. The most important disease vector (91.3%) for both human and animal rabies was the dog. A total of 41 human deaths due to rabies had been reported during the period, 2 being from Mazandaran.

Conclusion: The results show that a more effective disease control and surveillance system is essential and can help improve planning for service provision in the health care centers.

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Background and Aim: Length of stay (LOS) in a hospital is one of the best hospital indicators that can be used for various purposes. In this survey, we studied the hospital LOS and its associated factors in Tehran University of Medical Sciences Women's Hospital (a teaching hospital) in Tehran using the Cox proportional hazards semi parametric model and compared the results with the results obtained using the multiple linear regression.

Materials and Methods: This was a descriptive-analytical study in which we reviewed 3421 files of inpatients hospitalized in, and those discharged from, the oncology, surgery and obstetrics units in 2008. The required data were collected using a data collection sheet and inpatient interviews. A P<0.05 was considered statistically significant.

Results: The median of patients' LOS in the hospital was 50.8 hours, that in the obstetrics, surgical and oncology units being 48.5, 54.4 and 94.2 hours, respectively. Of all the patients, 2632 (76.9%) had been discharged with a recovery status and the rest (23.1%) with a no-recovery status. Results of the Cox proportional hazards model showed that the following variables had increased LOS: a distance longer than 200 km between a patent's residence and the hospital, hospitalization in the surgery and oncology units, admission on a Thursday, admission by an internist, hospitalization for neoplastic, endocrine, nutritional, or genitourinary system diseases (P<0.005), as well as a high number of diagnostic laboratory tests, radiographies or sonographies (P<0.001). Patients admitted and hospitalized as an emergency case had a shorter LOS (P<0.001) than others. On the other hand, based on the multiple linear regression model results, some occupations (being a worker, a farmer, a stockbreeder, or a retired spouse) admission on a Thursday, (The first day of the weekend in Iran), suffering from a neoplastic disease, and a high number of diagnostic tests or radiographies or sonographies increased, and admission by a resident decreased, patients' LOS (P<0.05).

Conclusion: Considering having censored data, the Cox proportional hazards model is a more suitable model than the multiple linear regression models for identifying factors influencing patients' LOS in a hospital. From among the LOS Cox model's associated factors as identified in this study, policy-makers and managers can only change admission days and the number of diagnostic tests. That is to say, they should try to prevent admission on a Thursday (unless emergency cases) and also perform the required primary diagnostic tests before admitting a patient into the hospital, which would lead to a more effective utilization of hospital beds and other resources.

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Background and Aim: Today cardiovascular diseases are the main cause of disability and mortality in many countries. This study was performed to determine the effect of health education based on the Health Belief Model on the knowledge, attitude and practice of housewives in Isfahan, Iran regarding improving their nutritional behavior for preventing heart disease.

Materials and Methods: This was a quasi-experimental intervention, including 68 Isfahani housewives randomly divided into an experimental (n=34) and a control (n=34) group. Data were collected using a standard health belief model (HBM) and a food-frequency (FFQ) questionnaire. The experimental group attended, after a pre-test, 6 weekly education sessions. The HBM questionnaire was completed 3 times (before and immediately, and 2 months, after education), while the FFQ questionnaire was completed twice (before and 2 months after education) by the housewives. The data were analyzed using SPSS16 software, the statistical tests being t-test, and repeated measure ANOVA.

Results: The two groups were not significantly different with regard to demographic variables. Similarly, before the intervention they were statistically similar with respect to the scores of the HBM components (P>0.05). After the intervention, significant differences appeared between the experimental and the control groups with regard to all the components (knowledge, perceived susceptibility, perceived severity, perceived benefits, perceived barriers, perceived efficacy, and performance in all cases, P<0.001)

Conclusion: Based on the findings, it can be concluded that the intervention had a positive impact on the feeding pattern of the women and was effective in increasing or improving their knowledge, attitude and practice.

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Background and Aim: Specific and unique characteristics of nanoparticles may entail specific and unique hazards. In addition, they may also exhibit toxicity under certain conditions. This study was conducted to investigate the toxicity of phenol-exposed and phenol-unexposed nano-TiO2 and nano-Fe/TiO2 particles.
Materials and Methods: Stock solutions of the afore-mentioned nanoparticles were prepared at different concentrations and a sample of each was exposed to phenol. This was followed by exposing Daphnia Magna to the phenol- and non-phenol-exposed nanoparticles. LC50, NOEC and the concentrations at which mortality rates were 100% were determined 12 to 96 hours after exposure, while for the determination of the mortality rate of Daphnia the Probit model in SPSS version16 software was used.
Results: The results revealed that (1). The 48-hr LC50 values for phenol-unexposed nano-TiO2 and nano-Fe/TiO2 particles were 2705 and over 15000 mg/m3, respectively. The corresponding values for the phenol-exposed samples were 414 and 1253. (2). The 48-hr NOEC values for the phenol-exposed TiO2 and FeTiO2 were 41 and 789, respectively, the corresponding values for unexposed samples being 1253 and over 15000 mg/m3. (3). In addition, the 48-hr 100% mortality rates for phenol-unexposed nano-TiO2 and nano-Fe/TiO2 particles were, respectively, 1253 and over 15000 mg/m3, while for the phenol-exposed samples the corresponding rates were 1090 and over 2108.
Conclusion: With regard to 48-hr LC50, the findings show that the toxicity of both nano-Fe: TiO2 and TiO2 increases as a result of exposure to phenol, the increase being 12-fold for the former and 6.5-fold for the latter. In general, however, based on LC50, it can be said that the toxicity of Fe:TiO2 nanoparticles, which has better catalytic characteristics, is lower in comparison to TiO2 nanoparticles. Thus, using Fe:TiO2 in preference to pure TiO2 should be investigated further, as it will be less hazardous to the environment.