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261.
The aim of this study was to investigate the work ability in ageing workers suffering from osteoarthritis (OA), coronary heart disease (CHD) or hypertension (H). One hundred and sixty-six OA and 355 CHD/H outpatients were evaluated. The Work Ability Index (WAI) served for work ability assessment. Patients' results were compared with the results of a control group of 225 healthy young workers. Statistical analysis was performed with ANOVA tests. WAI in female and male CHD/H patients was higher than in OA patients (p < .01), better work ability was related to better education (p < .01), white-collar work (p < .01) and better recreation (p < .01); subjective work ability was determined mostly by the objective health status. The promotion of work ability among workers suffering from advanced age-related diseases should be closely related to the promotion of health. It is indicative to improve occupational education and skills, already at an early stage of a disease.  相似文献   
262.
Polymeric microspheres with N-methyl-d-glucamine (NMDG) ligands have been tested in the adsorption–membrane filtration process for boron removal from aqueous solutions. The chelating resins were synthesized by reacting NMDG with the vinylbenzyl chloride–styrene–1,4-divinylbenzene (VBC/S/DVB) copolymer at the reflux temperature and in the microwave reactor. VBC/S/DVB spheres with a gel structure that contained 6 wt% DVB were obtained by membrane emulsification followed by suspension polymerization. By selecting the optimal emulsification and polymerization parameters, it was possible to obtain 25-μm-diameter particles with a narrow size distribution. Resins obtained by microwave modification showed the higher boron adsorption capacity.  相似文献   
263.
The infiltration of rainfall into contaminated soils and wastes provides the mechanism whereby hazardous chemical and radionuclide constituents of concern are leached and transported to underlying groundwater and potential human and ecological receptors. The application of engineered covers to reduce rainfall infiltration is an approach that is often selected for the remediation of contaminated sites. Evapotranspiration, or water‐balance, cover designs have been shown to be effective ways of preventing infiltration in arid and semiarid climates. This particular design relies on evaporation and vegetative transpiration to reduce potential infiltration to acceptable levels. In this article, we identify and examine the dominant ecological processes that affect the performance of evapotranspiration cover designs. © 2012 Wiley Periodicals, Inc.  相似文献   
264.
It is possible to develop large quantities of energy by installing a comprehensive regional insulation program. This paper develops a computer model for examining the quantity of energy that may be saved in a region if such a program is undertaken. The program requires data on: number of houses, type of houses and present degree of insulation. The results indicate that in the region under consideration it is possible to make available more energy, far cheaper, through insulation than by the alternative of constructing a large power plant.  相似文献   
265.
We compared levels of eight heavy metals in common tern eggs collected in 1982 (n=24) from coastal New Jersey with archived specimens collected from the same colonies in 1971 (N=9). Levels of all metals, except cobalt, showed a significant decrease over the 11 year period, with lead and nickel showing the greatest decline. Mercury levels declined over 50% based on geometric means. Cadmium and mercury showed the lowest levels in both years. Pair-wise correlation coefficients on log-transformed data revealed lower correlations in 1971, whereas most metal pairs showed significant correlations in 1982. Mercury levels showed significant positive correlations with cobalt, cadmium, and nickel in 1971, but were not correlated with levels of any other metal in 1982.  相似文献   
266.
We analyzed cadmium and lead levels in feathers of mated pairs of common terns (Sterna hirundo) and in their eggs to determine if metal levels in eggs correlated with female levels, and whether there were intrapair and intermetal correlations. Eggs had significantly lower lead levels (89 ng g-1) and cadmium levels (4.0 ng g-1) than adult feathers (500 and 50 ng g-1 respectively). Adult females had higher metal levels than males. Cadmium and lead levels were correlated across families for females, males and eggs. Lead, but not cadmium, levels were correlated in females and their eggs.  相似文献   
267.
Mercury bioaccumulation in organisms from three Puerto Rican estuaries   总被引:1,自引:0,他引:1  
We analyzed mercury levels in shrimp (Palaemonetes sp.), Blue Crabs (Callinectes sp.), fish (Tarpon Megalops atlantica and Tilapia Tilapia mossambica), lizards (Ameiva exsul), Cattle Egret (Bubulcus ibis) and Moorhen (Gallinula chloropus) in three estuaries in Puerto Rico in 1988. There were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site. Mercury levels were also below detection limits in Tilapia, except for specimens collected at Frontera Creek, allegedly contaminated with mercury. However, mercury levels ranged from 92–238 g/kg (wet weight) in Tarpon, a predaceous fish that feeds on smaller fish. Few of the birds had detectable levels of mercury. Our results indicate relatively low concentrations of mercury in biota collected in all of the three estuaries at most trophic levels, although 10 of 12 Tarpon fillet samples from Frontera had detectable mercury compared to 3 of 12 fillet samples for the other two lagoons.This project was partially funded by an EPA consent decree (Dynamac, Inc.) and NIEHS grant (ESO 5022) to EOSHI.  相似文献   
268.
Information on the spatial distribution and speciation of metals in nonhyperaccumulator plants is lacking. This study used synchrotron X-ray fluorescence (SXRF) compositional imaging to investigate the spatial distribution of Ni, Mn, Cu, Zn, and Fe in annual rings of black willow (Salix nigra L.) collected from a metal-contaminated area, and used X-ray absorption spectroscopy (XAS) to investigate Ni and Mn speciation in regions of the annual rings with elevated Ni concentrations. Annual rings were recollected in early 2003 from an individual known to be enriched with Ni from previous studies. Compositional imaging showed Ni and associated co-contaminants conservatively located in an annual ring. When compared with a corresponding photomicrograph, SXRF compositional images showed that metals were sharply constrained by the boundaries of the annual ring, indicating a sudden onset and cessation of uptake, and a lack of post-growth mobility of the metals. There was a particularly strong correlation between Ni and Mn in the metal-enriched annual ring (r = 0.8822), which suggested similar transport and binding behavior of these elements. X-ray absorption spectroscopy showed Ni and Mn to be present in the 2+ oxidation state. X-ray absorption near edge structure spectroscopy (XANES) fingerprinting of localized, highly Ni-enriched regions within the lumen of willow xylem vessels found similarities with Ni-pectic acid complexes, Ni-histidine, and NiSO4.  相似文献   
269.
270.
This article presents a database developed to determine the potential reuse of contaminated sites for primarily ecologically and culturally based activities. The database consists of 172 quantitative and qualitative measures of on‐site land suitability, ecological, cultural, and recreational value, and off‐site suitability, economic, and demographic information. Using sites owned by the U.S. Department of Energy (DOE) as a case study, the article evaluates the quality of available data and suggests ways of using it for planning ecologically sensitive remediation activities and future land use. This type of database can be developed and used by anyone who needs to select, review, or evaluate site remediation and future land use options. Also discussed are the challenges associated with compiling and using data that has been generated by many sources over several years. © 2003 Wiley Periodicals, Inc.  相似文献   
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