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331.
The dynamics of physiological stress and thermal balance were investigated in men subjected to endogenous and exogenous heat loads. The study was conducted using the thermometric method. Substantial differences in the dynamics of the tested parameters and their quantitative characteristics were observed in 1 out of 8 participants. In this article, the observed differences are rationalized in terms of the deficient sweat rate mechanism. It is pointed out that it is indispensable to address these cases in work safety regulations.  相似文献   
332.
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   
333.
A territorial male can shift the location of its territory from year to year in order to increase its quality. The male can base its decision on environmental cues or else on its breeding experiences (when territory shift is caused by breeding failure in previous seasons). We tested these possible mechanisms of territory choice in the sedge warbler (Acrocephalus schoenobaenus), a territorial migrating passerine that occupies wetlands. This species bases its territory choices on an environmental cue: tall wetland vegetation cover. We found that the magnitude of territory quality improvement between seasons (measured as the area of tall wetland vegetation) increased throughout the early stages of a male's breeding career as a result of territory shifts dependent on the earliness of arrival. The distance the territory was shifted between seasons depended negatively on the previous year's territory quality and, less clearly, on the previous year's mating success. On the other hand, previous mating or nesting success had no influence on territory quality improvement between seasons as measured in terms of vegetation. The results imply that tall wetland vegetation is a long-term, effective environmental cue and that a preference for territories in which this type of landcover prevails has evolved into a rigid behavioral mechanism, supplemented by short-term individual experiences of breeding failure.  相似文献   
334.
The paper is concerned with estimation of heat and power consumption in a conceptual plant to produce hydrogen from sucrose-containing or starchy biomass by fermentation. A hydrogen plant connected with a sugar factory is regarded as the basic option; the sugar factory serves as a source of sucrose-containing thick juice for the hydrogen plant, where this feedstock is processed to hydrogen. As another option, a stand-alone hydrogen plant in which starch must initially be converted to fermentable glucose solution is considered. The values of key process parameters are assumed on the basis of preliminary experimental data. For both options of the hydrogen plant, heat consumption is estimated taking heat recovery in a heat exchanger network into account. Power consumption is estimated by calculating power needed for pumping of liquid and gaseous process media.  相似文献   
335.
Living in an area chronically polluted with metals is usually associated with changes in the energy distribution in organisms due to increased energy expenses associated with detoxification and excretion processes. These expenses may be reflected in the available energy resources, such as lipids, carbohydrates, and proteins. In this context, the energy status of Pterostichus oblongopunctatus (Coleoptera: Carabidae) was studied in two metal pollution gradients near Olkusz and Miateczko ?l?skie in southern Poland. Both regions are rich in metal ores, and the two largest Polish zinc smelters have been operating there since the 1970s. Beetles were collected from five sites at each gradient. Zinc and cadmium concentrations were measured in both the soil and the beetles. The possible reduction in energy reserves as a cost of detoxifying assimilated metals was evaluated biochemically by determining the total lipid, carbohydrates, and protein contents. At the most polluted sites, the Zn concentration in the soil organic layer reached 2,906 mg/kg, and the Cd concentration reached 55 mg/kg. Body Zn and Cd concentrations increased with increasing soil Zn and Cd concentrations (p?=?0.003 and p?=?0.0001, respectively). However, no relationship between pollution level and energetic reserves was found. The results suggest that populations of P. oblongopunctatus inhabiting highly metal-polluted sites are able to survive without any serious impact on their energy reserves, though they obviously have to cope with elevated body metal concentrations.  相似文献   
336.
337.
Pesticides that contain a halogen functional group have been destructed by means of detonative combustion. The following compounds were examined: (1) atrazine—2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine—herbicide; (2) bromophos—O,4-bromo-2,5-dichlorophenyl O,O-dimethyl phosphorothioate—insecticide; (3) chloridazon—5-amino-4-chloro-2-phenylopyridazin-3(2H)-one—herbicide; (4) linuron—3-(3,4-dichlorophenyl)-1-metoxy-1-methylurea—herbicide; (5) metoxychlor—1,1,1-trichloro-2,2-bis(4-metoxyphenyl)ethane—insecticide and acaricide; and (6) trichlorfon—dimethyl 2,2,2-trichloro-1-hydroxyethylphosphonate—insecticide. Explosive material has been produced on the basis of ammonium nitrate, which served as an oxidizer while the pesticides were used as fuels. Composition of the explosive was adjusted in such a way as to respect thermodynamic parameters. Detonative decomposition of the mixtures has been carried out in shot-holes pre-drilled in soil. Efficiency of the pesticide decomposition has been examined with gas chromatography in order to determine pesticides residues in the environment. It was found that for some, the amount of pesticides in some compounds in the analyzed samples after decomposition was below the determination threshold of the applied method.  相似文献   
338.
339.
Seasonal changes in lipid, glycogen, protein (Nx6.25), and ash content of the meat of Macoma balthica (L.) from five sampling sites in the Gulf of Gdask were studied from 1981 to 1984. Lipid and glycogen were stored mainly during spring and at the beginning of summer. The lipid content of up to 36% of the dry weight observed in populations from the Gulf of Gdask are among the highest values reported for bivalve molluscs. Potential causes of this high value are discussed.  相似文献   
340.
This paper presents a general model for energy flow through an animal organism whose consumption and assimilation processes can be described by continuous functions. Two versions of the model are discussed: with continuous and with discrete reproduction. Also, their applicability in analyzing the properties of an actual modelled system is discussed. The results of sensitivity analysis and optimization considerations are presented.  相似文献   
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