Anthropometric hand dimensions in a population of Iranian male workers in 2012

Background. The mismatch between the hand size of workers and the size of industrial instruments is a growing concern; it can lead to various musculoskeletal complications. Currently, there are few reliable studies available to address this concern in Iran. This study was conducted to measure 30 upper-extremity parameters in a group of Iranian industrial workers. Methods. This study is a cross-sectional study on 529 workers. The study population was randomly selected from male Iranian industrial workers who were referred to the Yazd hospital occupational medicine clinic for surveillance evaluations. Results. The M (SD) age of the participants was 30.13 (8.29) years. Statistical analysis was performed using the mean, standard deviation and 5th, 50th and 90th percentiles for each measured hand dimension. A considerable number of dimensions were significantly different between the measurements of right and left hands in each examinee. The results showed significant differences between Iranian hand size and that of other populations. Conclusion. This study provided a valuable databank of hand dimensions in a population of Iranian male workers. These data can be used by manufacturers in designing high-quality hand-tools and industrial gloves, taking into consideration Iranian worker characteristics.     

Relationship of extinction coefficient, air pollution, and meteorological parameters in an urban area during 2007 to 2009

Light extinction, which is the extent of attenuation of light signal for every distance traveled by light in the absence of special weather conditions (e.g., fog and rain), can be expressed as the sum of scattering and absorption effects of aerosols. In this paper, diurnal and seasonal variations of the extinction coefficient are investigated for the urban areas of Tehran from 2007 to 2009. Cases of visibility impairment that were concurrent with reports of fog, mist, precipitation, or relative humidity above 90 % are filtered. The mean value and standard deviation of daily extinction are 0.49 and 0.39 km^?1, respectively. The average is much higher than that in many other large cities in the world, indicating the rather poor air quality over Tehran. The extinction coefficient shows obvious diurnal variations in each season, with a peak in the morning that is more pronounced in the wintertime. Also, there is a very slight increasing trend in the annual variations of atmospheric extinction coefficient, which suggests that air quality has regressed since 2007. The horizontal extinction coefficient decreased from January to July in each year and then increased between July and December, with the maximum value in the winter. Diurnal variation of extinction is often associated with small values for low relative humidity (RH), but increases significantly at higher RH. Annual correlation analysis shows that there is a positive correlation between the extinction coefficient and RH, CO, PM₁₀, SO₂, and NO₂ concentration, while negative correlation exists between the extinction and T, WS, and O₃, implying their unfavorable impact on extinction variation. The extinction budget was derived from multiple regression equations using the regression coefficients. On average, 44 % of the extinction is from suspended particles, 3 % is from air molecules, about 5 % is from NO₂ absorption, 0.35 % is from RH, and approximately 48 % is unaccounted for, which may represent errors in the data as well as contribution of other atmospheric constituents omitted from the analysis. Stronger regression equation is achieved in the summer, meaning that the extinction is more predictable in this season using pollutant concentrations.     

Adsorption and photocatalytic properties of porphyrin loaded MIL-101 (Cr) in methylene blue degradation

Environmental Science and Pollution Research - In this study for the very first time, zinc tetraphenylporphyrin (ZnTPP) was loaded into MIL-101 (Zn[TPP]@MIL-101) to perform an adsorptive and...     

Carbon footprint calculation in one of the largest Gas Refinery Companies in the Middle East

Environmental Science and Pollution Research - Rapid technological advances in the natural gas industry raised access to natural gas reserves, related to increased greenhouse gas emissions,...     

A case–control study on the relationship between urine trace element levels and autism spectrum disorder among Iranian children

Autism spectrum disorder (ASD) is a type of neurodevelopmental disorder characterized mainly by qualitative deficiencies in social communication skills, accompanied by repetitive and restricted behavior patterns. This study was conducted to investigate the associations between the risk of ASD development in children and exposure to trace elements (arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), lead (Pb), nickel (Ni), and zinc (Zn)). Two groups of children, including 44 ASD and 35 typically developing (TD) children, were selected, and their fasting urine samples were obtained. The concentration levels of trace elements were assayed using ICP-MS. The results showed that as compared to the TD group, the concentration levels of As (p = 0.002) and Pb (p < 0.001) and also Cr (p < 0.001), Cu (p = 0.001), and Ni (p < 0.001) were significantly higher among ASD children. In terms of gender, boys with ASD showed elevated levels of Cr, Cu, Ni, and Pb, whereas the urine levels of As, Cr, Cu, Ni, and Pb were markedly higher among girls when compared to the non-ASD children. Under the logistic regression model, the risk difference for As, Co, Cr, Cu, Ni, Pb, and Zn remained significant when adjustment was applied for age and gender confounders.

     

Multivariate statistical evaluation of heavy metals in the urine of opium individuals in comparison with healthy people in Western Iran

Environmental Science and Pollution Research - The current study aimed to evaluate the levels of some toxic and essential elements (Pb, Cd, Cu, Ti, Ni, Cr, Co, Fe, Ca, Hg, Mn, Se, and Zn) in the...