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471.
It has previously been shown that the level of Daphnia proteins detected by commonly used anti-HSP antibodies, with molecular weights corresponding to those of heat shock proteins, can be modified by various kinds of stress, including the threat of predation. In this study, we demonstrate for the first time that these proteins change their expression in response to thermal stress. Thus, it is concluded that Daphnia heat shock proteins, as components of the cellular stress defense, are involved in both, abiotic and biotic stress.  相似文献   
472.
Two-year old Ulmus laevis Pall (U. laevis) seedlings were cultivated in a three-month hydroponic experiment with inorganic (aresenite – As(III) and arsenate – As(V)) and organic (dimethylarsenic acid – DMA(V)) arsenic forms, at 0.06 and/or 0.6?mM concentrations. Further, the profile and content of total low molecular weight organic acids (LMWOAs) were investigated in the rhizosphere, roots and leaves of U. laevis. Obtained results showed that the addition of As(III) or As(V) individually or in a mixture led to increased LMWOAs concentration in the rhizosphere, especially of oxalic and malonic acids, in comparison to the control, while in roots the overall content of the profiled LMWOAs decreased. In both rhizosphere and roots, addition of the DMA(V) form resulted in the inhibition of LMWOAs exudation into the rhizosphere and their creation in plant roots. Leaves were characterised by a higher content of LMWOAs than in the rhizosphere and roots for all experimental systems, where the profile and content of LMWOAs was strictly correlated with the analysed As forms. Our study indicated that creation of LMWOAs in U. laevis organs and their exudation to the rhizosphere could be responsible for the As toxicity tolerance of the plants.  相似文献   
473.
EOX in sediments from the two main Polish rivers (the Vistula and the Oder/Odra) as well as five lakes was assayed coulometrically and its values examined with respect to the location of the sample collection points. EOX values were found to increase near industrial areas and large urban agglomerations, although mean values--comparable for rivers and lakes--were similar to those recorded elsewhere. EOX tends to rise as TOC does so. On the other hand, the EOX:TOC ratio decreases sharply in the case of lakes, since TOC values there are roughly one order of magnitude higher than in rivers. Furthermore, the contents of selected polychlorinated biphenyls and organochlorine pesticides are directly related to EOX values. These relationships constitute a basis for the application of EOX as a parameter reflecting the level of organochlorine compounds in environmental quality evaluation.  相似文献   
474.
This paper presents and discusses the results of (239+240)Pu determinations in different components of Gdańsk bay and Gdańsk basin ecosystem, as well as estimated sources and inventories of plutonium in these basins. The total plutonium (239+240)Pu activities deposited in Gdańsk bay and Gdańsk basin sediments are 1.18 TBq and 3.77 TBq, respectively. Two rivers, the Vistula and Neman rivers, and atmospheric fallout were distinguished as the main sources of plutonium in these basins. In seawater (with suspended matter included) there is about 2.33 GBq (239+240)Pu (0.2% of total activity) in Gdańsk bay and 9.92 GBq (239+240)Pu (0.3% of total activity) in Gdańsk basin. In both cases, 56% of (239+240)Pu is associated with suspended matter. Organisms contain 3.81 MBq in Gdańsk bay and 7.45 MBq (239+240)Pu in Gdańsk basin. From this value in Gdańsk bay 82.1% of plutonium is associated with zoobenthos, 13.6% with phytobenthos, 1.6% with phytoplankton, 1.5% with zooplankton and 1.2% with fish. In Gdańsk basin, 83.2% is associated with zoobenthos, 7.5% with phytobenthos, 3.6% with phytoplankton, 3.2% with zooplankton and 2.5% with fish.  相似文献   
475.
The toxicity of mononitrophenols and dinitrophenols (DNP) to luminescent bacteria Vibrio fischeri (Microtox test) and ciliated protozoan Spirostomum ambiguum (Spirotox test) was evaluated. Spirotox was more sensitive to the tested nitrophenols (NPs) than the Microtox test. 2,5-DNP was the most toxic and 2-NP was the least toxic to the both bioindicators. The toxicity depended greatly on the pH of the medium. The highest changes were observed for DNPs, where the toxicity decreased more than 20-times when the pH increased from 6 to 8. No significant decrease of the toxicity was found for NPs, when the pH increased from 6 to 7. Greater increase of the pH to 8 caused from 1.5 to 4-fold decrease of the toxicity.  相似文献   
476.
477.
Contents of mineral substance, silica, and a range of bioelements and toxic elements (Mg, Na, K, Ca, Ba, Zn, Cr, P Al, Cd, Mn Cu, Ni, Pb, Sr, Fe) in 38 livers of donors from the Upper Silesia Coal Basin (southern Poland) are presented. Elements were determined by inductively coupled plasma-atomic emission spectrometry (ICP-AES) with the exception of silica that was estimated colorimetrically. Concentrations, concentration variability, and correlations between selected liver components determined for the total population are related to donor age, gender, and lesion occurrence. Correlations between particular elements were found using correlation coefficient values and the Fisher transformation. Mineral substance in the livers lies in the range 0.40–5.03 wt%. With increasing donor age, mineral-matter content decreases to a minimum for the 40–60 years of age range. Microbioelement contents show a similar tendency, while microbioelements and toxic elements reach maximum contents in donors aged 60–80 years. All elements show content decreases in livers from the oldest group (>80 years). Silica contents increase with age. Variability of element contents is lowest in the older subpopulations. Livers with lesions show lower element contents and variability. The results are compared to literature data for regions of Poland assumed to be of low pollution and to data from comparable regions in Japan and Hungary. Up to our knowledge, this paper is the first work describing the total contents, as distinct from contents of selected elements, of mineral substance in human livers.  相似文献   
478.
The purpose of this study was to determine the usefulness of physiological studies in the evaluation of protective clothing for work in a cold environment. The study included the examination of the dynamics of changes in chosen physiological parameters (core and skin temperatures, heart rate, pulmonary minute ventilation) as well as physical ones (the temperature and relative humidity under the clothes) during work in protective clothing with unknown thermal insulation. The experiment was conducted in extreme environmental conditions (–10 and –15°C) at a work load defined by the clothing manufacturer as moderate. Results show that thermal equilibrium was achieved and maintained throughout the investigated work time (60 min) and that the protective clothing ensures safety on the time scale of a regular 8-hour work day. It was also shown that the dynamics of thermal stress physiological parameters can be used to determine the maximum duration of exposure for cold protective clothing with unknown thermal insulation.  相似文献   
479.
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   
480.
The aim of the study was to develop a set of curricula for teaching Occupational Safety and Ergonomics at colleges and universities of various types, aimed at equipping students with knowledge and skills and at shaping active attitudes towards the practical application of the acquired knowledge in their future working lives. On the basis of the analysis of the curricula at Polish and foreign colleges and universities, a set (canon) of educational contents constituting a common practice in the academic teaching of Occupational Safety and Ergonomics was established. Then, a convenient for teaching this subject classification of university specialisations in Poland was introduced. This led to identifying and defining a taxonomic unit called here an educational profile. Next, curriculum minima for the developed profiles were defined objectively. To achieve this aim, the set of educational contents was ranked by university teachers and specialists in occupational safety and ergonomics. Each part of the educational contents (subject) was ranked on a 10-point scale in relation to each educational profile. The results of this ranking led to formulating sets of educational contents for each educational profile. On this basis, a repertoire of curricula (6 curricula, in 2 hour-by-hour versions each) was prepared, with methodological guidelines for lecturers. The results of the study were presented in the form of a manual for academic authorities.  相似文献   
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