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41.
The aim of this study is to investigate changes in cardiovascular activity associated with a high mental workload. The reported experiments, carried out in naturalistic settings, point to information load and information processing under time pressure as main risk factors. This kind of occupational stress had to be dealt with by two of the three groups under investigation: brokers and simultaneous interpreters; it was not experienced by lecturing university professors. The pattern of cardiovascular activity of the two former groups consisted of overmobilization of cardiovascular activity at the beginning of work, and only partial normalization of task-evoked changes in cardiovascular activity at the end of work. Substantial elevations of diastolic blood pressure and tachycardia, which followed earlier overmobilization, resemble a miniature copy of changes seen in the development of cardiovascular diseases.  相似文献   
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43.
Results of long-term radioecological investigations in areas with an enhanced level of natural radioactivity in the north of Russia are summarized. Deleterious changes within animal and plant populations inhabiting areas with an enhanced level of natural radioactivity in the Komi Republic were revealed. These changes are expressed in enhanced levels of mutagenesis, destructive processes in the tissues of animals, disturbances of reproductive functions and reduced offspring viability. Compensatory processes, resulting in animal and plant survival under extremely adverse conditions of radium and uranium-radium contamination, were observed as well. However, obvious signs of adaptation failed to be detected. The findings suggest that adverse somatic and genetic effects are possible in plants and animals in the dose range observed at sites with an enhanced level of natural radioactivity. In contrast, different plant species inhabiting an area with an enhanced level of natural radioactivity in the taiga zone of the Sakha Republic (Yakutia) reveal a stimulation of growth processes, photosynthesis, endogenous low molecular weight antioxidant synthesis as well as adaptive response. It is apparent from the data presented that naturally occurring differences in terrestrial radiation level could be of genetic and ecological consequence.  相似文献   
44.
The effect of mine tailings and sewage sludge was evaluated on sorption, desorption, availability and distribution of copper in two soils, one high (sandy soil) and one low in copper (clay soil). In both soils contaminated by mine tailings the copper sorption capacity and the affinity of the substrate for the metal decreased substantially compared to the uncontaminated soils, however, the sorption remained always high in the clay soil substrates. In the substrates with sandy soil, the high Cu content and lower clay content were determining factors in the lower magnitude of the sorption. Similarly, metal desorption was closely related to these two parameters, and it was higher in clay soil with lower pH. In general, the application of sewage sludge favored the sorption of Cu in soils contaminated and uncontaminated with mine tailings, and in all cases desorption decreased, an effect that remained for at least 30 days. Simple extraction of Cu with CaCl2 and diethylenetriaminepentaacetic acid gave contradictory results, so a careful choice of the procedure is required, depending on the level of metal in the soil and on the acting principle of the extracting agent. In that relation, more complete information on the changes in the metal forms was obtained by application of the sequential extraction procedure proposed by the European Community Bureau of Reference.  相似文献   
45.
Biological control agents have become a useful alternative for the reduction of the use of chemical insecticides. LABIOFAM (Cuba) is developing a new formulation of a biolarvicide that possesses as active biological agent Bacillus thuringiensis var israelensis serotype H14. In order to evaluate the genotoxicity of this new formulation, an in vivo battery test was used: micronucleus (MN), chromosome aberrations (CAs), and sperm morphology (SM) assays. A dose of 6.45?×?108 spores was administered per animal via oral administration. Bone marrow cells were collected 24?h after a two day treatment for the MN assay, and 24?h after a unique treatment for the CA assay, using cyclophosphamide as the positive control. Sperm cells were collected at 5 weeks from the first of five administrations for the SM test, using acrylamide as positive control. Bacillus thuringiensis var israelensis serotype H14 failed to show either a significative increase of micronucleated polychromatic erythrocytes, chromosomal aberrations, or sperm abnormalities. Acute oral administration of a high dose of Bacillus thuringiensis var israelensis serotype H14 did not produce mutagenic effects in bone marrow or sperm cells.  相似文献   
46.

The spatial and temporal distribution pattern is an outstanding feature of the relationship among ecosystem services (ESs) that explains links between human activities and disturbed chemical composition of ecosystems. This study investigated the spatiotemporal variation of land use/cover changes (LUCC) and quantifies the change in four essential ecosystem services with an emphasis on soil (nutrient delivery ratio, carbon storage, crop production, and water yield) and their relationships in the Jiroft plain, Iran, during 1996–2016 through analytical tools including Land Change Modeler, and the Integrated Valuation of Ecosystem Services and Tradeoff. During the 20-year concentrate period, there was a considerable overall gain in cropland (5396 km2) and urban (1787 km2), loss of unused land (5692 km2), water (2088 km2), and forest (1083 km2). As a result of LUCC, while crop production and nutrient delivery ratio showed a rising trend, overall carbon storage and water yield decreased. The spatiotemporal trade-off between carbon storage and crop production, the temporal trade-off between crop production and water yield, and synergy between water yield and crop production were widespread in Jiroft plain. These results showed that the interaction among ESs mutates over time and can be changed under planning and policies. This study will enrich the research of the geographical distribution of ESs interaction in dryland ecosystems to provide practical ecosystem management under local conditions.

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47.
The present study reports the herbicidal activity of metribuzin and tribenuron-methyl embedded in the degradable matrix of natural poly-3-hydroxybutyrate [P(3HB)/MET and P(3HB)/TBM]. The developed formulations were constructed as films and microgranules, which were tested against the weeds such as white sweet clover Melilotus albus and lamb's quarters Chenopodium album in the presence of soft spring wheat (Triticum aestivum, cv. Altaiskaya 70) as the subject crop for investigation. The activity was measured in laboratory scale experiments by determining the density and weight of the vegetative organs of weeds. The study was also aimed at testing the effect of the experimental formulation on the growth of wheat crop as dependent on the method of herbicide delivery. The experimental MET and TBM formulations showed pronounced herbicidal activity against the weed species used in the study. The effectiveness of the experimental formulations in inhibiting weed growth was comparable to and, sometimes, higher than that of the commercial formulations (positive control). The amount of the biomass of the wheat treated with the experimental herbicide formulations was significantly greater than that of the wheat treated with commercial formulations.  相似文献   
48.
Problem of wildfires has not been resolved anywhere in the world. Mere increase of technical power does not lead to desirable results. Forests of developed countries burn as actively as those in Africa or in Russia. The main reasons of wildfire problem are as follows: (1) Constant wandering of dry seasons over the planet causing outbreaks of wildfires. (2) Unpredicted self-development of ordinary wildfires into awful fire disasters. (3) Difficulties in delivery and use of heavy machines on hardly accessible territories. (4) Absence of a perfect technique for economic evaluation of how effectively the wildfire control system works. (5) Absence of the system of payments encouraging wildfire fighters. To solve the problem of wildfires in Russia it is necessary to: (1) Create the Russian wildfire behaviour and fire effects prediction system on the basis of the developed classification of vegetation fuels and methods of their mapping as well as maximum utilization of forest inventory information and Geographic Information System (GIS). (2) Elaborate a technique of proper wildfire monitoring including estimation of vegetation damage. (3) Improve daily rating of regional fire danger. (4) Improve fire-preventive arrangement of the territory covered by vegetation, the main goal being creation of favourable conditions for active fire management. (5) Choose the main direction in elaboration of fire-fighting means and methods taking into account their universality, simplicity, reliability, etc. (6) Elaborate an improved technique for estimation of economic effectiveness of the wildfire control system. (7) Develop international cooperation of scientists and professionals in fire management.  相似文献   
49.
The paper explores the impact and sustainability of environmental assistance coming to Russia from EU-based public and private foundations, and its implications for environmental governance. Geographically, the study ’encompassed all the assistance projects awarded in 1991–2016 involving beneficiaries from Pskovskaya Oblast’. This region is potentially an important target for EU investments in environmental infrastructure, due to its location by the EU border and high value of natural capital. The study demonstrates how the assumptions offered by the international aid literature (mostly derived from the global South) apply to Russia. We found major limitations to the assumption that co-financing provided by recipients ensures project effectiveness (demonstrating the acceptance of the donor's agenda) or sustainability (providing interest to the maintenance of outputs). Tangible assets are normally co-financed only if the investment was in agenda anyway (and therefore the donor gets only time gains, although this can be a valid purpose too); soft outputs (plans, surveys, policies, etc.) are usually co-financed in-kind, and therefore cannot secure any additional commitment. Likewise, physical infrastructure often ends up mismanaged due to low or no maintenance budgets available, while maintenance of soft outputs is too much dependent on contextual factors beyond the co-finance paradigm.  相似文献   
50.
In the Russian Arctic, nature protection is important to preserve valuable ecosystems and indigenous lifestyles against the rapidly expanding oil and gas activities. In this regard, zoning legitimately balances influential stakeholders versus weak ones, and can leverage stakeholders to exercise their rights. This study explores how various stakeholders employ zoning in the Numto Nature Park in the oil-rich Russian Khanty-Mansi Autonomous Okrug–Yugra to advance their interests and how they use scientific information to achieve this. Through stakeholder interviews, analysis of electronic media and literature review, we conclude that a participatory and science-based zoning exercise stimulates the necessary deliberation. However, legal ambiguity, deficient law implementation and informal practices limit the zoning's potential to balance stakeholders’ interests. All the stakeholders calculatingly used scientific information to legitimize their own ambitions, activities and claims. Hence, zoning and the underlying information claims should be interpreted as both a resource and a battleground in nature-use conflicts.  相似文献   
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