Tibbi-i-kar

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Introduction: In previous studies the appearance of vitiligo following occupational exposure has been defined. This study evaluates high risk occupational exposures before the onset of disease among patients with vitiligo Methods: All vitiliginous patients refered to dermatologic clinic of Imam Hospital, were asked about age of onset, recent and previous occupations, risky occupational exposures, autoimmune systemic disease and family history. Laboratory evaluation about diabetis melitus and thyroid disease was performed. Results: Of 135 patients included in the study, 70 (51.85%) patients had an occupation and 65 (48.14%) were unemployed. Of 70 occupational cases, 23 (32.9%) had a risky occupational exposure. The most prevalent risky occupational exposures were exposure to detergents, oil colour, print dye and pesticides. Occupational cases were divided into two groups: with risky occupational exposure and without risky exposure. In risky occupational exposure group, the ratio of men to women was significantly higher. There was a significant difference in distribution of the disease between two groups and extremities were significantly more involved in risky exposure group. Age at onset was significantly lower in non-risky exposure group. None of the patients with risky occupational exposure used skin protction. Conclusion: High prevalence of risky occupational exposure may indicate it as a risk factor for vitiligo. Knowledge about these risky chemicals and prevention, may reduce occupational vitiligo.

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Background: This study aimed to evaluate ergonomic behaviors and to determine the importance of each ergonomic behavior in an Iranian petrochemical company. This study was conducted in Khuzestan petrochemical company, which is located in the south of Iran, in 2010. Methods: The methodology was based on the Ergonomic Behavior Sampling (EBS), and by entropy. After specifying the non-ergonomic behaviors and with reference to the results of a pilot study, a sample of 1755 was determined, with a sampling accuracy of 5% and confidence level of 95%, however, in order to have more confidence, 2631 observations were done. Results: The results indicated that 43.6% of workers' behaviors were unsafe. The most frequent non- ergonomic behaviors were using of legs for load lifting (83%). The highest and lowest weights, which are obtained by entropy, belong to load carrying with correct weight behavior and neck posture behavior with weight of 0.370 and 0.0052, respectively. Conclusion: Taking into account catastrophic consequences of accidents in petrochemical industry, the results show the importance of paying attention to safety principles and to develop a positive attitude among employees toward safety

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Introduction: Appropriate office workstation design and adjusted keyboard slope could prevent upper extremity musculoskeletal disorders caused by CTDs. The purpose of this study was to compare wrist and finger motion angles during typing in different workstations with different keyboard slopes.

Methods: In this experimental study, 10 female typists of university workers were chosen randomly. Test was performed on two different adjustable and non-adjustable chairs with four different keyboard slopes including 15, 7, 0, -7 degrees. Wrist and fingers kinematic data were calculated by Vicon motion analysis system and MATLAB software.

Results: Average wrist flexion angles were significantly different in different keyboard slopes. In adjustable workstation, the lowest mean value of maximum, average, min mum of flexion was measured for keyboard whose slope was adjusted to 15 degrees. The lowest mean for observed flexion in the metacarpophalangeal joints in the second and fifth fingers was measured in workstation with adjustable seats and keyboard whose slope was adjusted to 15 degrees. In the proximal interphalangeal joint of the second finger, the lowest mean was obtained in the workplace with adjustable seats and the keyboard whose slope was adjusted to 15 degrees.

Conclusion: During typing on keyboard, as much as the finger joint angles are close to zero degree, less stress is put on the joints. In this study, the lowest means for the degrees of joint flexion were observed in the workstations with adjustable seats and the keyboard with 15-degree slope.

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Introduction: Fatigue and sleepiness can negatively affect driver’s consciousness and their cognitive function. Traffic accidents due to sleepiness are more common among people who work more than 60 hours a week, or have irregular working hours or night shifts.

Methods: Last available literature and the most authentic sources were assessed and different aspects of the issue were evaluated.

Results: Drowsy driving increases the risk of a crash four times. Fatigue reduces performance in tasks that require alertness, manipulation and retrieval of stored information. There are several instruments to measure drivers’ sleepiness including Multiple Sleep Latency Test, Maintenance of Wakefulness Test, Epworth Sleepiness Scale, Karolinska Sleepiness Scale, and Stanford Sleepiness Scale.

Conclusion: Careful consideration and scientific approach to professional drivers’ work schedule to prevent sleepiness, fatigue, and driving for long and consecutive hours and also the study of underlying sleep diseases, are highly important.

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Introduction: Cognitive ergonomics is a branch of ergonomics science that investigates the impact of environmental conditions on subjective and objective individual performance. Music is known as an effective environmental factor on human performance. The aim of present study is to examine the effect of three different types of music tempo.
Method: In this study, students were randomly divided into 4 groups: iranian pop music, traditional music, Mozart classical music and control groups. In the music group, music was played during Wechsler test accomplishment, while no music was played for the control group. All participants were tested again with an interval of one week, once with music and once without music (except of the control group).
Results: The mean of Wechsler test score after playing music in classic group (22.88±2.42), which was higher than control group (20.94±3.20), pop group (20.36±4.21) and traditional group (19.87±4.90), and this difference was statistically significant (P<0.05). In addition, mean of working memory score, before (20.29±3.20) and after (22.88±2.42) playing the music in classic group, was increased about 2.59 after playing music, and the difference was significant (P<0.01).
Conclusion: This study shows that listening to classic music can improve working memory performance of students. Therefore, it is recommended to display classic music in workplaces, where memory function is important to improve the work.
 

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Objective: In this study we assessed the effect of bright light emitted by light box on fatigue, and sleepiness in nurses.
Methods: 44 healthy female shift work nurses were allocated into two groups of intervention and control. In the first stage, bright light was emitted to the nurses in the intervention group by the light box, and bright light was not emitted to the control group. In the next stage (one month later), we emitted bright light to the control group of first stage and vice versa (cross over). Main outcome measure, we assessed after intervention were fatigue and sleepiness. We measured fatigue (Visual Analogue Scale) and, sleepiness (Karolinska Scale), every hour, during next 24 hours.
Results: Almost all the time during 24 hours of the assessment of Visual Analogue Scale the trend of changes in two groups were in opposite direction. The mean value of two groups were statistically different.  In addition, about Karolinska Sleepiness Scale, the effect of intervention on the mean values of KSS during 24 hours was significant and the mean values in two groups were significantly different and the trend of changes in two groups were in opposite direction.
Conclusion: The bright light exposure in nurses resulted in changing the trend of fatigue in opposite direction compared to the controls. The minimum of fatigue occurred at 4 am which was time of maximum fatigue in controls. Also, the trend of changes of KSS was in opposite direction in cases and minimum sleepiness was at 4 am.