effect of noise on human performance: a clinical trial

Noise is defined as unwanted or meaningless sound that apart from auditory adverse health effects may distract attention from cues that are important for task performance. Human performance is influenced by many job-related factors and workplace conditions including noise level. To study the effect of noise on human performance. The participants included 40 healthy male university students. The experimental design consisted of 3 [sound pressure level] x 3 [noise schedule] x 2 [noise type] factors. To investigate occupational skill performance, some specific test batteries were used: 1] steadiness test, 2] Minnesota manual dexterity test, 3] hand tool dexterity test, and 4] two-arm coordination test. Time duration of test completion was measured as speed response; to determine error response, the time taken during committing an error by participants while performing a task was measured. Speed response obtained from the 4 tests in combined conditions of noise schedule, harmonic index, and sound pressure level was highest for [intermittent, treble, 95 dB], [continuous, treble, 95 dB], [continuous, treble, 85 dB] and [intermittent, treble, 95 dB], respectively. Treble noise was found significant in reducing human performance; also, intermittent noise, especially at high pressure levels, was responsible for worsening environmental conditions during performing a task

[Introducing the standard and chart to measure and control the motorcycle noise level]

Sound of motorcycles plays an important role in noise pollution in big cities. This is due to the lack of national law or standards to control the noise of domestic and also imported motorcycles. This study tries to introduce a practical limit value in different stage of motorcycle life cycle by assessing their noise pollution. First the motorcycles noise standards at different countries were studied and they were compared with the results from noise level of 622 motorcycles in 3 different groups. The sample volume in each group corresponds to the amount of their annual production rate. Then using statistical tests, a limit was determined in which 90% of the domestic motorcycles can be covered. The limit is proposed as the standard for domestic motorcycle noise. The limit for motorcycles of groups 1, 2 and 3were 84, 86 and 87 dB [A], respectively in the TA stage. For the COP stage [Conformity of Production], the limit increases according to certain formula. In the end, a flowchart was proposed as a standard method for measuring the sound of motorcycles in the TA and COP stages was proposed. Noise level of the domestic motorcycles is at least 9 dB [A] higher than the noise limit value of European motorcycle. If European limit value is considered for producing the national motorcycle, 90% of them will get out of production cycle and this would not be practical

study of the status of electromagnetic waves resulting from BTS [base transceiver station], 900 megahertz frequency in Tehran

with the developments of technology, contact with various frequencies of electromagnetic fields [EMF] has significantly increased, while the abundant benefits of using microwaves in routine life cannot be neglected. During recent years there have been reports of adverse effects caused by contact with electric and magnetic fields of these waves that spread from BTS antennas. The purpose of this study is the measurement of microwaves spreading around BTS antennas in Tehran. according to the location of BTS antennas in Tehran, power density of electromagnetic waves around 63 antennas in near and distant fields in different distances was measured. The measurements were performed using the standard method of IEEE Std C95.1 by Hi-4333 device .in order to analysis data we used spss 16 and descriptive and deductive statistical tests. results of this study show that in the near field, with increase of distance from the foot of antenna, the average power density of electromagnetic waves increase in a way that in the distance of 10 meters from the antenna foot, the increase of average power density is hardly conceivable and from 10 to 15 meters distance is perfectly noticeable. But in the distant field, with increase of distance from 20 meters, the average power density of the electromagnetic waves decreases; and from 100 meter and further, the gradient of the diagram will get almost linear and the rate of power density reaches the base limit in a way that with the increase of distance there would be no significant decrease. All the measures of power density of electromagnetic waves caused by BTSs are about 0.06% of recommended measures of environmental standards and 0.0000013% of occupational standards. The results of this study are close to the results of other studies

Investigation of management status on medical wastes in public hospitals of Arak city

Not paying attention to management and control of medical wastes in different stages of production, keeping, gathering, transporting and finally eliminating them all have been creating various setbacks such that the environment and human's health are in danger with the relevant consequences. This descriptive cross-sectional study was performed in Vali-e Asr, Amir Kabir, Taleghani, Amir Al-Momenin and Imam Khomeini hospitals of Arak city in 2009. In this research the current condition of gathering, maintaining, transportation and final elimination of hospital wastes of Arak city was investigated .Eventually an appropriate model was introduced. Solid wastes were separated, weighed and registered in two sequential intervals. In order to get acquaintance with the management procedure of medical solid w;astes in the hospitals studied, a questionnaire approved by W.H.O was used. The questions were then replied by the Managers and Hygiene Experts worked at hospitals and their responses were recorded. The investigations conducted in 5 hospitals reveal that the average per annual was2.9 Kg in 24 hours per active bed and 4.6 Kg for each patient. This volume consists of 60% for semi-home solid wastes, 39% for infectious solid wastes, 0.34% for sharp wastes, 0.28% for the pathologic and 0.38% for medicinal and chemical solid wastes. According to the results obtained in this study, in order to reduce pollution create in the hospitals, action should be taken to deal with pollutants at their source of generation. The staff members involved in waste collection and transportation should practice all the personal protection measures.finaly it also should be considered that, success in medical waste management wouldn't be achievable unless all groups of medical staff involved cooperate and participle

[Relationship between DNMT1 gene's SNPs and colorectal cancer at Taleghani hospital in Tehran]

The relation between Single Nucleotide Polymorphisms [SNPs] and a number of diseases has triggered many researches. Investigating the possible relations between SNPs present in DNMT1 gene from man's chromosome 19 and colorectal cancer. This was a case/control study in which 100 patients with colorectal cancer, referred to Research Center of Gastroenterology and Liver Diseases of Shaheed Beheshti Medical University during 2008, were chosen as case group. The control group included an equal number of patients who visited the medical center for a variety of reasons. Genetic test was carried out on all patients to determine the type of 6 SNPs of DNMT1 gene from man's chromosome 19. Data were statistically analyzed by SPSS software using chi-square test and logistic regression. All SNPs investigated showed significant relations with colorectal cancer indicating that in all cases the chance of getting colorectal cancer in people with genotype 1 and 2 was much higher than those with genotype 0. by exploring people's SNPs, it is feasible to predict the risk of catching colorectal cancer and thus establishing proper preventive measures

Application of acoustical processor reactors for degradation of diazinon from surface water

Since organophosphorus pesticides are widely used for industry and insect control in agricultural crops, their fate in the environment is very important. Pesticide contamination of surface water has been recognized as a major contaminant in world because of their potential toxicity towards human and animals. The objective of this research was to investigate the influence of various parameters including the iniluence oftime. power, and initial concentration on degradation of diazinon pesticide. The sonochemical degradation of diazinon was investigated using acoustical processor reactor. Acoustical processor reactor with 130 kHz was used to study the degradation of pesticide solution. Samples were analyzed using HPLC at different time intervals. Effectiveness of APR at different times [20, 40, 60, 80, 100, and 120 min], concentrations [2. 4 and 8 mg/L] and powers [300W, 400W, 500W] were compared. The degradation of the diazinon at lower concentrations was greater in comparison to higher concentrations. There was also direct correlation between power and diazinon degradation. In addition, when the power increased, the ability to degraded diazinon increased. The sonodegradation of diazinon pesticide at different concentrations and powers was successfully provided. It has been shown that APR can be used to reduce the concentration of dissolved pesticide using high frequency

Assessment of medical waste management in educational hospitals of Tehran University Medical Sciences

The management of medical waste is of great importance due to its potential environmental hazards and public health risks. In the past, medical waste was often mixed with municipal solid waste and disposed in residential waste landfills or improper treatment facilities in Iran. In recent years, many efforts have been made by environmental regulatory agencies and waste generators to better managing the wastes from healthcare facilities. This study was carried in 12 educational hospitals of Tehran University of Medical Sciences. The goals of this study were to characterize solid wastes generated in healthcare hospitals, to report the current status of medical waste management and to provide a framework for the safe management of these wastes at the considered hospitals. The methodology was descriptive, cross-sectional and consisted of the use of surveys and interviews with the authorities of the healthcare facilities and with personnel involved in the management of the wastes. The results showed that medical wastes generated in hospitals were extremely heterogeneous in composition. 42% of wastes were collected in containers and plastic bags. In 75% of hospitals, the stay-time in storage sites was about 12-24h. 92% of medical wastes of hospitals were collected by covered-trucks. In 46% of hospitals, transferring of medical wastes to temporary stations was done manually. The average of waste generation rates in the hospitals was estimated to be 4.42kg/bed/day

Heat exposure assessment in the working environment of a glass manufacturing unit

Heat stress is a common health problem throughout industry. Any heat stress evaluation requires some exposure assessment of climatic conditions, especially air temperature, humidity, and speed, along with the average temperature of the solid surroundings. In this paper workplace environmental climatic parameters were measured and then evaluated by Wet Bulb Globe Temperature, Corrected Effective Temperature, Heat Stress Index, and Allowable Exposure Time indices among 40 workers in a glass manufacturing unit in Tehran. Also, the effect of available heat control devices on heat stress indices was investigated. The results of this study showed that the obtained heat stress index in individual section and press units is exceeded from 100 [in individual section unit: 302.6, in press unit: 283.6]. Also, it is found that the mean average of allowable exposure time in individual section and press units were 13.15 and 12.26 minutes exposure for one hour, respectively. No significant relationship was found between environmental parameters in three parts of body regions [height of head, abdomen and ankle] except for measured air velocity in both units [P<0.007]. Positive correlation was found between wet bulb globe temperature, corrected effective temperature and heat stress index indices, but negative correlation was found between allowable exposure time and other indices. Mann Whitney non-parametric test revealed significant relationships in wet bulb globe temperature, corrected effective temperature, heat stress index and allowable exposure time indices when metallic shield was used as heat absorber

[Evaluation of X-Ray factors and its effect on radiology department staff at Army hospitals in Tehran in the year 1385]

Knowledge of X-Ray related factors connected with individual dosimeter can be beneficial in diminishing the rate of x-ray intake. Keeping in mind the above mentioned goal, we planned and prepared this study with the help of all radiology staff of the hospital. This research is a descriptive, analytic and a sectional study which was performed in the year 1385. All radiology staff of the army hospitals in Tehran was bulk examples. A check list and a questionnaire form were used to collect data and information. We also made use of SPSS software for data purpose. Results obtained in this study indicate that individual maximum dose received individually was 29/0 milisilvert; the rate of this dose was seen in persons who lacked University education. And a minimum dose received was 0/05 millisiurt which was received by individuals who were less than 30 hours in contact with the preparation of unison.. Many medical tests were performed at the following army hospitals: Golestan, 502, 204 and Mostafa Khomeini hospitals. The X-Ray rate at the mentioned hospitals was 100%. Dose received by all individuals as classified parameters expected was standard and acceptable. Therefore organizing X-ray safety workoshops especially in connection with promoting security level of unison production staff at all centers is an absolute must

[Study of short term effects of low level laser therapy [LLLT] vs. local steroid injection on patients with carpal tunnel syndrome]

Carpal tunnel syndrome is the most common entrapment neuropathy. Non-surgical treatment for carpal tunnel syndrome is frequently offered to those with mild to moderate symptoms. The effectiveness of some non-surgical treatment for carpal tunnel syndrome remain unknown. This study designed to compare the short term efficacy of local corticosteroid injection and laser treatment for mild to moderate idiopathic carpal tunnel syndrome. 44 hands in 33 consecutive patients with carpal tunnel syndrome confirmed by electrodiagnostic study were allocated randomly in two experimental groups. One group received local corticosteroid injection and the other received low level lasertherapy. Measurements were performed before and 8 weeks after treatments, and included pain assessment by visual analogue scale [VAS] and electrodiagnostic measurement [motor and sensory latencies and motor and sensory action potential amplitudes]. There was a significant symptomatic and electrodiagnostic improvement in both the injection and laser groups [P<0.05]. However, there was no significant difference in any of the outcome measures between the two groups [P>0.05]. LLLT was effective in treating carpal tunnel syndrome as well as local corticosteroid injection at least in short-term Long-term efficacy needs more investigation

Comparison of anteroposterior thickness of elite sprinters and distance runners' abdominal muscles

Abdominal muscles are known to have great effects on the locomotion and stabilization of trunk, as well as, contribution to the respiratory functions. These cited functions are of much importance, especially when an individual performs professional sport activities. The purpose of this study was to compare the effects of professional sprinting and distance running [track and field] activity, on the abdominal muscles of the respective athletes. 18 elite male runners [9 distance runners and 9 sprinters] were selected simply, with no randomization, aged 18-22 years. Measurement of abdominal muscles thickness was performed by a clinical ultrasonography machine, furnished with a curvilinear probe, emitting 7.5 MHz ultrasonic waves. Athletes were supine and still throughout the test, the probe was placed on two points of athletes' left abdomen, known as standard points for ultrasonography of abdominal muscles. The anteroposterior [AP] thicknesses of all abdominal muscles, had statistically significant differences between the two groups of runners, as the rectus abdominis muscle [RA] [P < 0.001]. Internal and external Oblique muscles [IO and EO] were thicker in the sprinters group; and in contrast, the transversus abdominis muscle [TA] owned more thickness among the distance runners [P < 0.05]. A long term physical exercise has specific effects on postural and motive muscles. So, sprinting sports have the most effect on postural muscles and distance running has the most effect on motive muscles

Training effect on the improvement of nutritional behaviours of the pregnant women referring to kermanshah health care centers

This is an interventional research. Its objective was to survey the effect of educational intervention on improvement of nutritional behaviours in pregnant women referring to kermanshah health care centers in 1384. This study was conducted on 180 pregnant women selected randomly [90 in intervention group and 90 in control group] and their gestational health services were provided in 9 urban health centers. Their nutritional knowledge, attitude and practice were assessed before implementation of educational program by using questionnaire. These variables were evaluated and analized one month after implementation of the program in intervention group. The results indicated no significant difference between control and intervention groups regarding the variables. Also the mean score of knowledge attitude and practice in control and intervention groups before education showed no significant difference. However the relationship between knowledge attitude and practice in the two groups before and after education was statistically significant. The mean of knowledge, attitude and practice scores increased significantly after education in intervention group [P<0/0001]. Regarding these results, positive effects of gestational nutrition education for pregnant women can be regarded as important. So we recommend a nutritional education program for pregnant women in the health care system

Evaluation of the effectiveness of health education on Knowledge and attitude of the Health volunteer women in Northern health centers of Tehran

Menopause complications lead to a reduction in women's life quality, so knowledge about menopause as a natural process in women's life is important on effective control of women's problem in these periods. The main purpose of this study was to evaluate effectiveness of health education on knowledge and attitude toward menopause among health volunteer women in the northern health centers of Tehran. In this quasi-experimental study [Before and After] randomized sampling method was employed, and 90 health volunteers participated from 9 health centers in the northern health centres of Tehran. The data were gathered using a questionnaire [including: demographic information, some questions related to knowledge and attitude]. They were assessed before and also one month after implementation of the educational program. Collected data were analyzed by SPSS [11.5]. The results indicated that 20% of the population had poor knowledge, whereas 62.2% had average level knowledge. Only 17.8% of the health volunteers had acceptable level of knowledge about menopause [symptoms, desired nutrition and regular exercise]. Their attitude toward menopause was undesired too. After the educational program 94.4% of the health volunteers had high knowledge and 88.9% of the sample had positive attitude about menopause. The findings suggest that it is necessary to perform such educational programs for health volunteers in health centers

Cotton dust exposure, respiratory symptoms and PEFR in textile workers

The purposes of this study was to measurement cotton dust levels in air workplace, Prevalence of respiratory symptoms and determine of changes in Peak Expiratory Flow Rate [PEFR] before and after during workday among textile workers. This study was done among 31 workers carding and blowing rooms. Using a short questionnaire for demographic characteristics, medical record were collected in a modified questionnaire of Occupational Safety and Health Administration [OSHA] and 12 air samples were collected of work area. The PEFR was measured with a peak flow meter. The mean cotton dust levels in carding and blowing rooms were 0.39 +/- 0.03 and 0.20 +/- 0.01 mg m 3, respectively. The mean age and year's employment were 45 +/- 7.97 and 12.5 +/- 6.28, respectively. Thirty three percent of the workers were smoking. The prevalence of respiratory symptoms increased with age and employment years and there were found significantly between age and employment years with cough, phlegm, dyspnea [p<0.05, 0.05, 0.05, respectively]. The mean PEFR before and after during workday were 362.9 +/- 147.8 and 305.8 +/- 147.5, respectively and subjects had found significantly [p<0.0001]. The decline in PEFR was significantly associated with years employment [p<0.05], whereas with age and cotton dust levels were found to be non significant. One explanation for thelack of age and cotton dust levels effects in workers may be due to the low number of subjects and samples, respectively. Technological improvement has resulted in reduction of cotton dust exposure levels and respiratory symptoms