Introduction. This review describes standardized ergonomics assessment based on pen-and-paper observational methods for assessing ergonomics risk factors. Objective. The three main objectives are to analyze published pen-and-paper observational methods, to extract and understand the risk levels of each method and to identify their associated health effects. Methodology. The authors searched scientific databases and the Internet for materials from 1970 to 2013 using the following keywords: ergo, posture, method, observational, postural angle, health effects, pain and diseases. Postural assessments of upper arms, lower arms, wrists, neck, back and legs in six pen-and-paper-based observational methods are highlighted, extracted in groups and linked with associated adverse health effects. Results. The literature reviewed showed strengths and limitations of published pen-and-paper-based observational methods in determining the work activities, risk levels and related postural angles to adverse health effects. This provided a better understanding of unsafe work postures and how to improve these postures. Conclusion. Many pen-and-paper-based observational methods have been developed. However, there are still many limitations of these methods. There is, therefore, a need to develop a new pen-and-paper-based observational method for assessing postural problems. 相似文献
Objectives: The objective of this study was to examine the association between dangerous student car drop-off behaviors and historical child pedestrian–motor vehicle collisions (PMVCs) near elementary schools in Toronto, Canada.
Methods: Police-reported child PMVCs during school travel times from 2000 to 2011 were mapped within 200 m of 118 elementary schools. Observers measured dangerous student morning car drop-off behaviors and number of children walking to school during one day in 2011. A composite score of school social disadvantage was obtained from the Toronto District School Board. Built environment and traffic features were mapped and included as covariates. A multivariate Poisson regression was used to model the rates of PMVC/number of children walking and dangerous student car drop-off behaviors, adjusting for the built environment and social disadvantage.
Results: There were 45 child PMVCs, with 29 (64%) sustaining minor injuries resulting in emergency department visits. The mean collision rate was 2.9/10,000 children walking/year (SD = 6.7). Dangerous drop-off behaviors were observed in 104 schools (88%). In the multivariate analysis, each additional dangerous drop-off behavior was associated with a 45% increase in collision rates (incident rate ratio [IRR] = 1.45, 95% confidence interval [CI], 1.02, 2.07). Higher speed roads (IRR = 1.27, 95% CI, 1.13, 1.44) and social disadvantage (IRR = 2.99, 95% CI, 1.03, 8.68) were associated with higher collision rates.
Conclusions: Dangerous student car drop-off behaviors were associated with historical nonfatal child PMVC rates during school travel times near schools. Some caution must be taken in interpreting these results due small number of events and limitations in the data collection, because collision data were collected historically over a 12-year period, whereas driving behavior was only observed on a single day in 2011. Targeted multifaceted intervention approaches related to the built environment, enforcement, and education could address dangerous drop-off behaviors near schools to reduce child PMVCs and promote safe walking to school. 相似文献
We have studied the genotoxic and apoptotic potential of ferric oxide nanoparticles(Fe_2O_3-NPs) in Raphanus sativus(radish).Fe_2O_3-NPs retarded the root length and seed germination in radish.Ultrathin sections of treated roots showed subcellular localization of Fe_2O_3-NPs,along with the appearance of damaged mitochondria and excessive vacuolization.Flow cytometric analysis of Fe_2O_3-NPs(1.0 mg/m L) treated groups exhibited 219.5%,161%,120.4% and 161.4% increase in intracellular reactive oxygen species(ROS),mitochondrial membrane potential(ΔΨm),nitric oxide(NO) and Ca2+influx in radish protoplasts.A concentration dependent increase in the antioxidative enzymes glutathione(GSH),catalase(CAT),superoxide dismutase(SOD) and lipid peroxidation(LPO) has been recorded.Comet assay showed a concentration dependent increase in deoxyribonucleic acid(DNA) strand breaks in Fe_2O_3-NPs treated groups.Cell cycle analysis revealed 88.4% of cells in sub-G1 apoptotic phase,suggesting cell death in Fe_2O_3-NPs(2.0 mg/m L) treated group.Taking together,the genotoxicity induced by Fe_2O_3-NPs highlights the importance of environmental risk associated with improper disposal of nanoparticles(NPs) and radish can serve as a good indicator for measuring the phytotoxicity of NPs grown in NP-polluted environment. 相似文献
Aquatic macrophytes are considered to be promising in controlling harmful cyanobacterial blooms. In this research, an aqueous extract of Sagittaria trifolia tubers was prepared to study its inhibitory effect on Microcystis aeruginosa in the laboratory. Several physiological indices of M. aeruginosa, in response to the environmental stress, were analyzed. Results showed that S. trifolia tuber aqueous extract significantly inhibited the growth of M. aeruginosa in a concentration-dependent way. The highest inhibition rate reached 90% after 6 day treatment. The Chlorophyll-a concentration of M. aeruginosa cells decreased from 343.1 to314.2 μg/L in the treatment group. The activities of superoxide dismutase and peroxidase and the content of reduced glutathione in M. aeruginosa cells initially increased as a response to the oxidative stress posed by S. trifolia tuber aqueous extract, but then decreased as time prolonged. The lipid peroxidation damage of the cyanobacterial cell membranes was reflected by the malondialdehyde level, which was notably higher in the treatment group compared with the controls. It was concluded that the oxidative damage of M. aeruginosa induced by S.trifolia tuber aqueous extract might be one of the mechanisms for the inhibitory effects. 相似文献