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51.
Purpose. To assess the reliability and validity of the Polish version of the 36-point World Health Organization Disability Assessment Schedule (WHODAS 2.0) in an elderly population. Method. One thousand randomly selected individuals, aged 60–70 years, living in south-eastern Poland were assessed using the Polish version of the WHODAS 2.0. Results. The analysis confirmed the high reliability and validity of the tool. Cronbach’s α index was 0.89. The tool had high stability, and the correlation between test and retest results was high. The relevance of the domain selection was high or very high. A factor analysis confirmed the relevance of assigning questions to domains. High theoretical relevance was also demonstrated. Statistically significant differences between those who were and were not suffering from health problems were observed. An analysis of the internal structure of the WHODAS 2.0 revealed strong correlations between the components of each domain and the final result. Conclusion. The Polish version of the WHODAS 2.0 showed high reliability and validity; thus, it can be used to assess health, functioning and disability in the elderly population of Poland.  相似文献   
52.
Industrial workplaces pose concurrent hazards to the upper part of the head and the eyes. Under the circumstances, workers may use protective helmets in conjunction with protective goggles or spectacles. In order to assess the compatibility of this equipment, a method and a test stand for evaluating the behavior of safety helmets and protective goggles/spectacles upon the impact of a falling weight were designed. The results of tests concerning the displacement and deformation of helmets and spectacles/goggles, the forces acting on the helmets, as well as the forces exerted by the spectacles/goggles on the headform upon falling weight impact are presented. The results revealed the ways in which the tested equipment interacted with each other. The influence of equipment construction on the test results was analyzed and inferences concerning the safety of the studied protective devices were made. Some general construction guidelines were formulated for the compatibility of the equipment.  相似文献   
53.
Pesticides cause serious environmental and health problems both to humans and animals. The aim of this review is to discuss selected herbicides and fungicides regarding their mode of action and their influence on basic oxidative stress parameters and endocrine disruption properties tested in selected cell cultures in vitro. Because of numerous difficulties which animal studies are subject to, cell cultures are an excellent experimental model reflecting human exposure to different pesticides through all relevant routes. This experimental model can be used to monitor aggregate and cumulative pesticide exposures.  相似文献   
54.
In this work, the main objectives were to assess the mutagenic and genotoxic effects of fine particulate matter collected in an industrial influenced site in comparison with a non-industrial influenced one (rural site) and to relate the particulate matter (PM) composition to the observed genotoxic effects. At the industrial influenced site, higher concentrations of phosphates, trace metals, and polycyclic aromatic hydrocarbons (PAHs) in particles could be related to the contributions of quarries, fertilizer producer, cement plants, and tires burning. Gasoline and diesel combustion contributions were evidenced in particles collected at both sites. Particles collected under industrial influence showed a higher mutagenic potential on three tested strains of Salmonella typhimurium (TA98, YG1041, and TA102), and especially on the YG1041, compared to particles from the rural site. Furthermore, only particles collected in the vicinity of the industrial site showed a tendency to activate the SOS responses in Escherichia coli PQ37, which is indicative of DNA damage as a result of exposure of the bacteria cells to the action of mutagenic samples. The mutagenicity and genotoxicity of the industrial PM2.5–0.3 particulates may be attributed to its composition especially in organic compounds. This study showed that proximity of industries can affect local PM composition as well as PM genotoxic and mutagenic potential.  相似文献   
55.
Nowadays our planet suffers from an accumulation of plastic products that have the potential to cause great harm to the environment in the form of air, water, and land pollution. Plastic water bottles have become a great problem in the environment because of the large numbers consumed throughout the world. Certain types of plastic bottles can be recycled but most of them are not. This paper describes an economical solvent-free process that converts polyethylene terephthalate (PET) bottles waste into carbon nanostructure materials via thermal dissociation in a closed system under autogenic pressure together with additives and/or catalyst, which can act as cluster nuclei for carbon nanostructure materials such as fullerenes and carbon nanotubes. This research succeeded in producing and controlling the microstructure of various forms of carbon nanoparticles from the PET waste by optimizing the preparation parameters in terms of time, additives, and amounts of catalyst.

Implications: Plastic water bottles are becoming a growing segment of the municipal solid waste stream in the world; some are recycled but many are left in landfill sites. Recycling PET bottles waste can positively impact the environment in several ways: for instance, reduced waste, resource conservation, energy conservation, reduced greenhouse gas emissions, and decreasing the amount of pollution in air and water sources. The main novelty of the present work is based on the acquisition of high-value carbon-based nanomaterials from PET waste by a simple solvent-free chemical technique. Thus, the prepared materials are considered to be promising, cheap, eco-friendly materials that may find use in different applications.  相似文献   

56.
Waters located at greater depths usually exhibit high mineral content, which necessitates the use of closed systems, i.e. re-injecting them into the formation after recovering the heat. This significantly reduces investment efficiency owing to the need to drill absorption wells and to perform anti-corrosion and anti-clogging procedures. In this paper, possibilities for the efficient utilisation of cooled geothermal waters are considered, particularly with respect to open or mixed geothermal water installations. Where cooled water desalination technologies are used, this allows the water to be demineralised and used to meet local needs (as drinking water and for leisure purposes). The retentate left as a by-product of the process contains valuable ingredients that can be used for balneological and/or leisure purposes. Thus, the technology for desalinating spent geothermal waters with high mineral content allows improved water management on a local scale and makes it possible to minimise the environmental threat resulting from the need to dump these waters into waterways or surface water bodies and/or inject them into the formation. The paper is concerned with Polish geothermal system and provides information about the parameters of Polish geothermal waters.  相似文献   
57.
Reservoirs situated along a river continuum are ecosystems where rates of transfer of suspended matter and associated micropollutants are reduced due to sedimentation, accumulation, and biological and physical transformation processes. Among the micropollutants, PCDDs and PCDFs are substances that are highly toxic and carcinogenic for humans and animals. They are emitted and dispersed in the environment throughout the whole catchment area and may accumulate in aquatic and terrestrial food chains, creating a risk for human health. A wealth of data exists indicating the increase in the concentrations of pollutants along a river continuum. A comparative analysis of total, individual, and TEQ PCDD/PCDF concentrations in large lowland, shallow reservoirs located in different catchments (“I”—industrial/urban/agricultural, “U”—urban/agricultural, and “A”—agricultural/rural) showed decreases of the TEQ concentrations in bottom sediments along a gradient from the middle sections to the dam walls. Moreover, penta-, hexa-, and heptachlorinated CDD/CDF congeners were reduced from 28.8 up to 93.6 % in all three types of reservoirs. A further analysis of water samples from the inlets and outlets of the “A” reservoir confirmed this tendency.  相似文献   
58.
Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were determined in 18 surface sediment samples collected from Bizerte lagoon, Tunisia. The total concentrations of ten PCBs (∑PCBs) and of four OCPs (∑OCPs) in the sediments from this area ranged from 0.8 to 14.6 ng g?1 dw (average value, 3.9 ng g?1 dw) and from 1.1 to 14.0 ng g?1 dw (average value, 3.3 ng g?1 dw), respectively. Among the OCPs, the range of concentrations of dichlorodiphenyltrichloroethane and its metabolites (DDTs) and hexachlorobenzene (HCB) were 0.3–11.5 ng g?1 dw (1.9 ng g?1 dw) and 0.6–2.5 ng g?1 dw (1.4 ng g?1 dw), respectively. Compositional analyses of the POPs indicated that PCB 153, 138 and 180 were the predominant congeners accounting for 60 % of the total PCBs. In addition, p,p′-DDT was found to be the dominant DDTs, demonstrating recent inputs in the environment. Compared with some other regions of the world, the Bizerte lagoon exhibited low levels of PCBs and moderate levels of HCB and DDTs. The high ratios ΣPCBs/ΣDDTs indicated predominant industrial versus agricultural activities in this area. According to the established guidelines for sediment quality, the risk of adverse biological effects from such levels of OCPs and PCBs, as recorded at most of the study sites, was insignificant. However, the higher concentrations in stations S1 and S3 could cause biological damage.  相似文献   
59.
The creation of metal parts via casting uses molds that are generally made from sand and phenolic resin. The waste generated after the casting process is called waste foundry sand (WFS). Depending on the mold composition and the casting process, WFS can contain substances that prevent its direct emission to the environment. In Brazil, this waste is classified according to the Standard ABNT NBR 10004:2004 as a waste Class II (Non-Inert). The recycling of this waste is limited because its characteristics change significantly after use. Although the use (or reuse) of this byproduct in civil construction is a technically feasible alternative, its effects must be evaluated, especially from mechanical and environmental points of view. Thus, the objective of this study is to investigate the effect of the use of WFS in the manufacture of cement artifacts, such as masonry blocks for walls, structural masonry blocks, and paving blocks. Blocks containing different concentrations of WFS (up to 75% by weight) were produced and evaluated using compressive strength tests (35 MPa at 28 days) and toxicity tests on Daphnia magna, Allium cepa (onion root), and Eisenia foetida (earthworm). The results showed that there was not a considerable reduction in the compressive strength, with values of 35 ± 2 MPa at 28 days. The toxicity study with the material obtained from leaching did not significantly interfere with the development of D. magna and E. foetida, but the growth of the A. cepa species was reduced. The study showed that the use of this waste in the production of concrete blocks is feasible from both mechanical and environmental points of view.  相似文献   
60.
Total mercury content has been determined in fruiting bodies of European Blushers and topsoils collected from 11 sites across Poland in 2006-2008. Mercury analysis was carried out using a validated analytical method and cold-vapour atomic absorption (CV-AAS). The European Blusher effectively accumulated mercury in fruiting bodies. The mean values of total mercury in caps of European Blushers from background (uncontaminated) areas were from 0.22 to 1.0 (0.067-3.2) and in stipes from 0.16 to 0.65 (0.071-2.7) μg/g dry weight. In topsoil beneath to fruiting bodies, the median Hg concentration at 10 sites in Northern Poland varied between 0.030 and 0.072 (0.0096–0.19) μg/g dw, and in one site in Southern Poland was 0.20 (0.079–0.34) μg/g dw. Data on Hg in European Blushers from different countries were reviewed. The mean concentrations of total Hg in caps of European Blushers from two “pristine” sites in northern part of Poland were ~1.0 μg/g dw. A meal made with 300–500 g of fresh caps of European Blushers collected at such sites (assuming 90% water content in caps) can result in Hg intake of 0.0003–0.0005 mg Hg/kg bm (assuming a 60 kg bm), which is a dose equipotent to a new provisional tolerable weekly intake (PTWI) value set for inorganic Hg.  相似文献   
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