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101.
This study describes some key ergonomic factors within the engine room, navigation bridge and other locations of a merchant ship. Ergonomic assessments were carried out on a crew of a merchant ship. The study examines the importance of factors such as noise, vibration, heat radiation (in machinery areas), psychological stress and ergonomics of the physical arrangement of the navigation bridge. It also addresses the effect of working in confined areas for a long duration and the need to process large amounts of data, decision-making and the influence of specific operating conditions in different areas of a ship. This study includes analysis of workstations, working methods and the burden of environmental factors as well as a discussion of specific marine environmental conditions such as confined working and leisure spaces, long-term family and sociocultural separation, frequent changes in climate and time zones, and temporary physical overload and long-term psychological burdens.  相似文献   
102.
Abstract

The use of electronic cigarettes increases as a supposedly healthier form of nicotine consumption, but safety of vaping remains uncertain. In this study, we assessed whether the use of electronic cigarettes increases the risk of infertility in male rats. Malformations of sperm morphology were more frequent in nicotine-exposed groups than in the control group. Vacuolization of seminiferous epithelium, reduction of spermatogenesis, increased apoptosis of spermatogonia and spermatocytes, and acceleration of degeneration of testes were observed. The male reproductive organs are slightly less affected by vaping than by smoking. Nevertheless, in consequence both may lead to the reduction of fertility.  相似文献   
103.
In recent years the issue of the municipal waste in Poland has become increasingly topical, with a considerable rise in the waste generation, much of which can be attributed to a boom in product packaging (mainly plastic). The annual production of plastics packaging has been constantly increasing over the last 20 to 30 years, and now exceeds 3.7 million tons. Due to a lack of processing technologies and poorly developed selective segregation system, packaging waste is still treated as a part of the municipal solid waste (MSW) stream, most of which is landfilled. As a result of Poland's access to the European Union, previous legal regulations governing municipal waste management have been harmonized with those binding on the member countries. One of the main changes, the most revolutionary one, is to make entrepreneurs liable for environmental risks resulting from the introduction of packaging to the market, and for its recycling. In practice, all entrepreneurs are to ensure recovery, and recycling, of used packaging from products introduced to the market at the required level. In recent year, the required recycling levels were fulfilled for all types of materials but mainly by large institutions using grouped and transport packaging waste for that matter. Household packaging gathered in the selective segregation system at the municipalities was practically left alone. This paper is an attempt to describe the system and assess the first year of functioning of the new, revamped system of packaging waste management in Poland. Recommendations are made relating to those features that need to be included in packaging waste management systems in order to maximize their sustainability and harmonization with the EU legal system.  相似文献   
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The village with its characteristic zones of different land use from the center to the periphery is a basic unit of Europe's cultural landscapes. However, loss of the authentic pre-industrial village structure characterized by a fine-grained structure of arable land and wooded grasslands is a threat to both cultural heritage and biodiversity in many rural landscapes. Therefore, it is important that the extent and rate of change of such authentic villages in a landscape can be monitored. We studied to what extent loss of authenticity with increasing time after abandonment can be assessed by quantitative analysis and visual interpretation of satellite images. The study was carried out in the Bieszczady Mountains, SE Poland in 1999. Using Landsat Thematic Mapper data from 1998, both the grain size of landscape elements (size of fields) and land-cover composition (encroachment of shrub and forest) were quantitatively described 6 type villages representing different stages of deterioration of the authentic village structure. Historical maps were used to delineate the border of the villages and the former extension of forest and open land was measured. The present land use and the degree of abandonment expressed as grain size and forest encroachment were mapped using satellite data. Deterioration occurred along 2 transformation paths: abandonment and ultimately becoming forest, or intensified agriculture, respectively. To validate these results we classified 22 other villages in a 1000 km2 area by visual interpretation of the original satellite images into 1 of 4 types. We then collected historical data on human population changes over the past six decades. The classification of village authenticity was clearly related to the rate of human population decline. We address the importance of validating and applying this approach for rapid assessment of the authenticity of cultural landscapes in European regions being subject to ongoing as well as expected future change, related to expansion of the European Union. Finally, we argue that the village represents a scale at which integration of natural and social sciences is possible.  相似文献   
108.
The leachability of heavy metals such as chromium (Cr), lead (Pb) and cadmium (Cd) from the ash material obtained from waste combustion was studied. The effects of ash surface topography and morphology on the leachability of these elements were examined using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The AFM (scan size 10 x 10 microns) and SEM images of the simulated ash pellet obtained at various operating temperatures (1000, 1400 and 1500 degrees C) showed significant microstructural and topographical changes. Ash pellets treated at 1000 degrees C contain porous and non-continuous surface. On the other hand, the ash pellet obtained at higher temperature (1500 degrees C) was found to contain a smooth, continuous and non-porous surface. The AFM height profile studies indicated that the top surface variation of the ash pellet at 1000, 1400 and 1500 degrees C were found to be -40.0 to 25.5, -3.7 to 4.7 and -0.10 to 0.66 nm respectively. The SEM analyses also confirmed the presence of smooth, non-porous outer surface of ash formed at 1500 degrees C. In addition, it also showed the presence of compact and rigid interior for the same ash pellet. The leachability of the heavy metals was determined using standard toxicity characteristic leaching procedure (TCLP) test and the samples were analysed using atomic absorption spectroscopy. The results showed that the TCLP leaching ratios of the heavy metals were Cr = 0.30, Pb = 0.05 and Cd = 0.09 at 1000 degrees C. However, the ash obtained at 1400 degrees C showed negligible heavy metals leaching ratio while at 1500 degrees C no leachability was detected (TCLP concentration dropped to nondetectable levels). The use of high temperature treatment enabled the immobilization of heavy metals in the ash preventing their leaching. Such ash can be considered as a non-hazardous material for reuse or safe disposal.  相似文献   
109.
Within the framework of the project "Effects of forest health on biodiversity with emphasis on air pollution in the Carpathian Mountains" 26 permanent study sites were established in the vicinity of the ozone monitoring sites. The study sites were located on the NW-SE transect through the Western (12 sites), Eastern (11 sites) and Southern (3 sites) Carpathians in forest ecosystems typical of each area. Some of the forest monitoring sites were located in national parks, biosphere reserves and areas of protected landscape. Each permanent site of 0.7 ha area consisted of 5 small 500m(2) circular plots, arranged in the form of a cross, i.e. four placed on the cardinal points (N, E, S, W) and one in the center. Phytosociological records were done twice during the 1998 growing season using the Braun-Blanquet's method. The study sites represented various types of forest: Picea abies stands (8), beech (Fagus sylvatica) stands (10), fir (Abies alba) stands (2) and mixed beech-fir, spruce-fir and beech-spruce stands (6). Age of most stands was 80-100 years. Degree of crown damage varied greatly between sites, a percentage of damaged trees decrease in Carpathians from West to East. It corresponds well with the O(3) level in these areas. Typical damage by O(3) in herb layer species in several Carpathian sites were found. Land-use map for the entire Carpathian Mountains and two detailed land use maps for Tatras (Western Carpathians) and Retezat (Southern Carpathians) are presented. A little more than half of the Carpathian territory is forested. The most densely forested are Eastern Carpathians, while the most sparsely Western Carpathians. Arable lands occupy 22.6% of the Carpathians, pastures and meadows 6.2%, water bodies 1.9%, and build up areas several percent. In the highest elevation of the Carpathians alpine meadows (11.3%) and rocks (3.5%) are distributed.  相似文献   
110.
Tadeusz Skowroński 《Chemosphere》1984,13(12):1379-1384
The investigations showed that Stichococcus bacillaris took up cadmium by means of adsorption and energy-dependent transport. Cadmium transport into alga cells was inhibited in the dark as well as under the influence of the uncouplers: 2,4-dinitrophenol (DNP), carbonyl cyanide m-chlorophenylhydrazone (CCCP), and ATPase inhibitor - N, N′ - dicyclohexylcarbodiimide (DCCD). It has also been stated that CCCP caused ATP level decrease in cells.  相似文献   
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