4 research outputs found
The effect of environmental factors on job Performance using manual and mental tests
Introduction: Individuals’ jobs performance is one the most important factors in industries and organizations. The aim of the present study was to investigate the simultaneous effect of exposure to noise, lighting and heat stress on the workers’ job performance.
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Material and Method: In this analytical-descriptive study, 30 employees of the auto parts manufacturer, in Tehran city, were chosen by simple random sampling. By controlling and limiting confounding factors, the simultaneous effect of noise, lighting and heat stress on the participants’ job performance was investigated, using tow series of mental and manual testes. Data were analyzed by SPSS software version 18, using descriptive statistic, ANOVA and Tukey testes and also person correlation coefficient.
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Result: The results showed that by increasing the noise and heat stress (P = 0.046, r=0.344) and decreasing of lighting (P =0.008, r = -0.472), the required time for performing the Minnesota placement test has been gone up. Moreover, the result revealed that by increase in noise and heat stress (P = 0.007, r = 0.478) and decrease in lighting (P=0.003, r = 0.523) the required time for competing hand tool dexterity test has been also increased at surface and mid level.
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Conclusion: Finding of the present research manifested that increase in noise and heat stress and also reduction in lighting lessen the speed of manual tests and time and accuracy of mathematical calculations. Therefore this result confirm the effects of various environmental factors on individuals’ job performance, in a way that by variation of different environmental factors, time of manual test and time and accuracy of mental tests would be changed
A simple and fast method based on new magnetic ion imprinted polymer as a highly selective sorbent for preconcentration and determination of cadmium in environmental samples
Background: The analysis of heavy metals at trace level is one of the main toxicologists concern, due to their vital rules in human`s life. Cadmium is one of these toxic heavy metals, which released to the environment from various industries. Methods: In order to determine Cd (II) ions in various matrices magnetic ion-imprinted polymer (IIP) method has been developed and applied. This nano-sorbent has been synthesized by coating an IIP compound on Fe3O4nanopar-ticles core to achieve highest surface area. This polymer has been used to evaluate Cd (II) levels in food, river, and wastewater in Tehran, Iran. Results: Fe3O4@Cd-IIP was stable up to 300 °C. The various factors such as sample pH (optimized as 7), elution/sorption time (5 min), eluent amount (4 mL HCL), and its concentration (2 mol L-1) were optimized. Analysis instrument in all steps was Flame Atomic Abortion Spectrophotometer (FAAS). In this study, the detection limit was determined down to 0.6 μg L-1. Conclusion: This method was applied successfully for the preconcentration and determination of Cd (II) ions in environmental samples obtained from rivers, various foods and wastewater. In addition, the accuracy of the method was confirmed by analyzing a certified reference material (Seronorm LOT NO2525) and spiked real samples. © 2016, Iranian Journal of Public Health. All rights reserved
Development of a selective sorbent based on a magnetic ion imprinted polymer for the preconcentration and FAAS determination of urinary cadmium
In this study, an ion imprinted polymer (IIP), based on coating of a polymer on a Fe3O4 nanoparticle (NP) core, is used as a magnetic sorbent for the preconcentration and determination of the Cd(ii) ion level in human urine samples. The synthesized polymer was characterized by IR spectroscopy, scanning electron microscopy (SEM), X-ray diffraction analysis (XRD) and thermal analysis (TG/DTA). The optimum conditions, such as pH of the sample, eluent volume, concentration and duration of sorption and elution, were investigated. In addition, the effect of some potentially interfering cations on the sorption of Cd(ii) was confirmed. In all samples, Cd(ii) was determined using a flame atomic absorption spectrophotometer. Under optimal conditions, the limit of detection (LOD) of cadmium was 0.6 μg L-1. The optimized method has been validated using day-to-day and within-day reproducible experiments and achieved appropriate accuracy and precision. The accuracy of the method was confirmed by analyzing a certified reference material (Seronorm LOT NO2525) and spiked real samples. Ultimately, this method was applied successfully for the preconcentration and determination of Cd(ii) ions in urine samples obtained from exposed individuals. This journal is © The Royal Society of Chemistry