Modeling important factors on occupational accident severity factor in the construction industry using a combination of artificial neural network and genetic algorithm.

BACKGROUND: Many occupational accidents annually occur worldwide. The construction industry injury is greater than the average injury to other industries. The severity of occupational accidents and the resulting injuries in these industries is very high and severe and several factors are involved in their occurrence. OBJECTIVE: Modeling important factors on occupational accident severity factor in the construction industry using a combination of artificial neural network and genetic algorithm. METHODS: In this study, occupational accidents were analyzed and modeled during five years at construction sites of 5 major projects affiliated with a gas turbine manufacturing company based on census sampling. 712 accidents with all the studied variables were selected for the study. The process was implemented in MATLAB software version 2018a using combined artificial neural network and genetic algorithm. Additional information was also collected through checklists and interviews. RESULTS: Mean and standard deviation of accident severity rate (ASR) were obtained 283.08±102.55 days. The structure of the model is 21, 42, 42, 2, indicating that the model consists of 21 inputs (selected feature), 42 neurons in the first hidden layer, 42 neurons in the second hidden layer, and 2 output neurons. The two methods of genetic algorithm and artificial neural network showed that the severity rate of accidents and occupational injuries in this industry follows a systemic flow and has different causes. CONCLUSION: The model created based on the selected parameters is able to predict the accident occurrence based on working conditions, which can help decision makers in developing preventive strategies.

Simplification of gold nanoparticle synthesis with low cytotoxicity using a greener approach: opening up new possibilities.

Gold nanoparticles (AuNPs) have diverse applications in the diagnosis and treatment of ailments. This study describes an extremely simplified synthesis of AuNPs using antioxidant-rich pollen extract as a local natural source. Ultraviolet-visible (UV-vis) spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) were used to characterize the synthesized AuNPs; strong UV-vis absorption at 534 nm confirmed their formation, the XRD pattern showed the presence of a crystalline structure, and TEM images showed them to be spherical nanoparticles with an average size of 9.3 ± 2.9 nm. As synthesized AuNPs remained stable for up to two months under laboratory conditions without any sedimentation or change in the absorption value, presumably due to the protection afforded by the capping agents from pollen. AuNPs revealed low toxicity effects on MCF-7 and HUVECs cell lines (with an IC50 value of ∼400 µg mL-1 for both the cell lines). The proposed method did not use any hazardous materials or high-energy consuming devices; thus this efficient protocol may be adapted for large-scale production using local resources.

Neurological risk assessment of co-exposure to heavy metals (chromium and nickel) in chromium-electroplating workers.

BACKGROUND: Metal co-exposure of human subjects is an important matter of public health concern. It has been shown that Acetylcholinesterase activity is a suitable biomarker for the neurological risk assessment of some metals. A few studies have reported neurotoxicity risk among humans in co-exposure to chromium and nickel. OBJECTIVE: In this study, AChE activity was assessed in occupational exposure to chromium (VI) and co-exposure to nickel (II) and chromium (VI). METHODS: Air sampling was done in chromium electroplating workshops with the NIOSH 7600 and OSHA ID-121 methods for chromium and nickel assessment. Thirty-two workers from hard chromium plating and 30 from decorative chromium plating were evaluated, while AChE activity was measured by the Elman method. RESULTS: Personal exposure to chromium in 20% of the studied people exceeded the TWA set by ACGIH. Occupational exposure to nickel in 47% of the DCP subjects was found to be higher than TWA. Cholinergic inhibition in plating workers was marked by a decrease in AChE compared to controls. Subjects with chromium (VI) exposure contained significantly higher inhibition of AChE activity (p < 0.001) than workers with co-exposure to nickel (II) and chromium (VI). CONCLUSIONS: The chromium-matched electroplaters have no significant difference in AChE activity. It can be concluded that cholinergic inhibition with chromium (VI) is higher than nickel (II) exposure.

Neurotoxicity effect of formaldehyde on occupational exposure and influence of individual susceptibility to some metabolism parameters.

Over the years, neurotoxicity and cognitive dysfunction have separately been associated with endogenous formaldehyde and reduction of acetylcholine signals. However, a limited number of studies have shown a relationship between cholinergic neurotransmitter and formaldehyde exposure. Therefore, the aim of this study was to assess the neurological effect on workers from melamine-dish preparation workshop, who were exposed to formaldehyde. A total of 35 formaldehyde-exposed workers were compared with 32 control employees from the food industry. Occupational exposure to formaldehyde was conducted using the National Institute of Occupational Safety and Health 3500 methods. Using the Ellman method, acetylcholinesterase (AChE) as a biomarker for neurotoxicity was analyzed in blood erythrocyte. The effects of alcohol dehydrogenase III (ADH3) and Mn-superoxide dismutase (Mn-SOD) polymorphism were used to survey the level of AChE activity. In this study, it was found that exposure to airborne formaldehyde increased from 0.024 to 0.74 ppm and the median personnel exposure was 0.057. Induction of AChE activity was observed in formaldehyde-exposed workers as compared with the control group (p < 0.01), while AChE activity increased in 64 % of the exposed subjects. Spearman's correlation (p < 0.02) was used to evaluate the association between AChE activity and occupational exposure to formaldehyde. Exposed subjects containing ADH32-2 genotype had higher AChE than others. The findings of this study suggest that the neurotoxic effect of formaldehyde depends on the AChE activity, which is affected by metabolism. It can be concluded that cholinergic signal reduction in cases of cognitive dysfunction could be associated with endogenous formaldehyde.