269 research outputs found
The Social Determinants of Risky Driving on the Intercity Roads of Tehran Province, Iran: A Case-Cohort Study
Background: Traffic accidents are the major cause of injuries that endanger the lives of many people annually. It seems that studying the factors and grounds of this type of event including risky driving contributes to the identification of groups at risk and development of preventive programs.
Objectives: Given the importance of this issue, we decided to conduct a study to examine the social factors of risky driving.
Methods: The present study was implemented based on a case-cohort design. The target community was all the drivers who drove on the intercity roads of Tehran Province. Each driver with and without a history of being guilty in a car accident leading to injury or death during the last 5 years was assigned to the case and control groups, respectively. The questionnaires were completed through a review of documents and interview within the groups. In the analytical analysis, a chi-square test and, if necessary, the odds ratio and confidence intervals were used to determine the relationship between the variables. In each case, the necessary investigation of confounding or interacting variables was performed using regression models and the final model of the factors affecting a risky driving was extracted.
Results: From a total of 990 drivers studied, 54 cases (5.5%) were females and 936 (94.5%) were males. The mean and SD of the drivers’ ages were 39.4 and 11.8 years, respectively. People with a driving job, chronic disease, poor socio-economic status, having only a family dispute, without a religious attitude, and under medical supervision (all with P < 0.001), secondary education (P = 0.01), women (P = 0.01), using drugs (P = 0.03) were found to have a greater history of road traffic injuries or deaths.
Conclusions: This study showed that gender, education level, occupation, socioeconomic status, medical care, health condition, lifestyle, family conflict, drug abuse history, and religious attitudes are the major social factors of risky driving on the intercity roads of Tehran Province
Specific heat and magnetocaloric effect in Pr1-xAgxMnO3 manganites
The magnetocaloric effect in alternating magnetic fields has been
investigated in Pr1-xAgxMnO3 manganites with x=0.05-0.25. The stepwise reversal
of the sign of the magnetocaloric effect has been revealed in a weakly doped
sample (x=0.05) at low temperatures (~80 K). This reversal is attributed to the
coexistence of the ferromagnetic and canted antiferromagnetic phases with
different critical temperatures.Comment: 4 pages, 4 figure
Incidence of self-reported interpersonal violence related physical injury in Iran
Background: Violence is the cause of death for 1.5 million people in a year. Objectives: Our study aimed to estimate the incidence rate of self-reported interpersonal violence related physical injury (VRPI) and its associated factors in Iran. Patients and Methods: The sample included people ranged from 15 to 64 years old who were residing in Iran. A total of 1525 clusters were selected from the whole country. Six families were selected from each cluster via a systematic random sampling method. Then, the residential units were identified and the interviewers contacted the inhabitants. In the next step, one of the family members was selected by using Kish grid method. The instrument was a researcher-made questionnaire and consisted of two sections; demographics and project related data. Face validity and content validity of our questionnaire were investigated based on expert opinions and the reliability was confirmed by a pilot study, as well. The inclusion criteria were considered for choosing the interviewers. An interviewer was assigned for each 42 participants (7 clusters). An educational seminar was held for the administrative managers (54 persons) and interviewers (230 persons) for a week. The field work was distributed among all 46 Medical Sciences universities in Iran. In each university, administrative issues were related to an executive director. Mann-Whitney U test and odds ratio were used to analyze the data with 95 confidence interval. α value was considered less than 5. Results: The frequency of VRPI among 7886 participants was 24 during the last three months. The incidence rate of interpersonal VRPI was estimated at 3.04 per 1000 population (95 CI: 2.66-3.42) during a three-month interval in Iran. The incidence was 4.72 per 1000 population (95 CI: 4.01-5.43) for males and 1.78 per 1000 population (95 CI: 1.39-2.17) for females during a three-month interval. The mean (SD) of age of the participants with and without a history of VRPI were 26.5 (7.21) and 33.05 (12.05) years, respectively (P = 0.008). Considering the participants� gender, 66.7 were males (OR = 2.66, 95 CI: 1.14-6.23). Khuzestan Province had the most VRPIs (25 of all VRPIs). Streets and roads were the places with the highest frequency of injury (50). The most frequent injured organ was the upper limb (54.17). The most prevalent type of injury was a superficial wound (50). Finally, the most common place of treatment was home (45.83). Conclusions: We determined the incidence rate of self-reported interpersonal VRPI for the first time in Iran based on a national survey. The injuries were more common among young men. We suggest consecutive national surveys with different data gathering methods and more sample sizes. © 2015, Iranian Red Crescent Medical Journal
First-principles study of structural, electronic and thermodynamic properties of (ZnO)(n=2-16) clusters
The structural, electronic, and vibrational thermodynamic properties of the
(ZnO) (n=2-16) clusters are studied using density functional - full
potential computations. The results show, small clusters up to stabilize
in the 2D ring shape geometries while the larger clusters prefer the 3D cage
like structures. The ring to cage structural cross over in ZnO clusters is
studied by investigating the behavior of the Zn-O-Zn bond angle, the Zn-O bond
strength, and the number of bonds in the systems. It is argued that 12 is the
lowest magic number of ZnO clusters at ground state, while finite temperature
vibrational excitations enhance the relative stability of the (ZnO) cluster
and make it a magic system at temperatures above about 170 K. The obtained
electronic structure of ZnO clusters before and after applying the many-body GW
corrections evidence a size induced red shift originated from the ring to cage
structural cross over in these systems. The behavior of the extremal points of
electron density of the clusters along with the extrapolated cluster binding
energies at very large sizes may be evidences for existence of a metastable
structure for large ZnO nanostructures, different with the bulk ZnO structure.Comment: 8 pages, 8 figures and 1 tabl
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