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121.
In 1996 the Swedish Poisons Information Centre performed a follow-up study concerning poisonings related to ‘do-it-yourself’ activities. The study was supported by the National Institute of Public Health in Sweden. The objectives were to investigate and define monthly variations, route of exposure, type of products and, in particular, exposures to corrosives, age and sex groups, place of treatment, severity of symptoms, place of the accident, special risk products and risk situations. The Poisons Information Centre was contacted concerning 1609 cases, with a peak during the summer months. There was no or uncertain connection between exposure and symptoms in 117 cases. This means that 1492 cases were left to study. Inhalation and eye exposure were the predominant routes, followed by skin exposure and ingestion. Cleaning agents were the most common type of products involved. Of the 1492 cases included in the study 1033 were possible to follow up. Among these, 20–29 year olds and 30–39 year olds predominated, and there was a dominance for men. In total, 28% of those exposed were subject to medical attention, either in hospital or in outpatient clinics. According to the Poisoning Severity Score 78% had mild (grade 1) and 7% moderate (grade 2) symptoms. There were no severe intoxications and no deaths. Severity grade 2 occurred 3.6 times more often among those with exposures involving risk of corrosive damage than among others in the study population. Most accidents occurred in the home. Special risk products and risk situations were exposure to corrosive products, release of chlorine when mixing hypochlorite and acid, ‘fire-eating’, siphoning gasoline and diesel fuel, welding, and inhalation of carbon monoxide from exhaust gases. The Swedish Poisons Information Centre registered 1609 cases of poisoning accidents during ‘do-it-yourself’ activities, which means an average of four to five cases per day. Although this type of accidents is not uncommon, significant poisoning seems to be rare. Some special risk situations were identified. 相似文献
122.
1999年7月,喀麦隆的一个小农合作社Macefcoop成功地将其头两集装箱有机咖啡装运到欧洲.这是从非洲进入“公平交易”市场的第一种有机咖啡.
在坦桑尼亚,卡格拉(Kagera)区两个村庄的农民(卡格拉合作联盟的成员)最后决定转向有认证的有机生产.
也在坦桑尼亚的乞力马扎罗土著合作联盟正在从事一个试验项目工作,以在他们的一个农场上引种有机咖啡,旨在向农民们示范何谓有机以及怎样才能实施有机生产.
这三个合作社全都是Max Havelaar基金会的注册伙伴....... 相似文献
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Knut Lehre Seip Gulbrand Lunde Sigurd Melsom Even Mehlum Angelika Melhuus Hans Martin Seip 《Ecological modelling》1979,6(2):133-166
A mathematical model has been developed to study the distribution and abundance of benthic algae species in a Norwegian fjord. The main forcing functions are the physical factors which have well defined gradients in this area, but biotic interactions are also accounted for in the model.The distribution of algae along vertical transects in the intermediate fjord area has been simulated, and the observed distribution is reproduced fairly well. This indicates that the major factors determining the equilibrium elevation between intertidal and subtidal vegetations in this area are adequately represented in the model.Based on observations in a fjord branch with a high level of freshwater influx and polluted by heavy metals, assumptions are made of the combined influence of these contaminants on growth characteristics of the species considered. The resulting effects on community development and community patterns are simulated. For a certain level of contamination, the decrease in abundance, community development rate and species separation have been determined. It is also shown that the fluctuations in biomass during a year are more pronounced than under unaffected conditions.The relative importance of external growth regulating factors and self-shading is demonstrated for different degrees of community development, and we have indicated that this may be an important factor in the assessment of transient and long-term responses to “natural” and man-made influences on the shore-line vegetation.One of the main problems during model development was the formulation of the interaction function for factors influencing growth parameters. Several alternatives were examined.The differences between the most frequently used forms were small with respect to abundance and not very large with respect to possible changes in distribution. It was noted that even by including only the most limiting factor at each instant, (Liebig's form) a high percentage of the potentially limiting factors did actually limit growth during periods of the year.The model is intended as a working tool for the studies of changes in the shore-line vegetation caused by man-made interferences like heavy metal and oil pollution, and we believe that the results presented demonstrate that it can successfully be used for this purpose. 相似文献
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127.
Hans Lück 《Die Naturwissenschaften》1957,44(15):423-423
128.
Hans Elsässer 《Die Naturwissenschaften》1979,66(6):279-285
In recent years several hitherto unknown types of celestial objects related to star formation and early stellar evolution have been discovered by infrared and radio observations. New stars are born within large and massive interstellar molecular clouds. The onset of star formation in these clouds seems to be triggered by external forces. 相似文献
129.
Hans W. Gottinger 《Environment international》1983,9(3):207-220
Based on a feasibility study, we have recently proposed a multivariate regression model for the impact of air pollution on the mortality of a long-term exposed population. This article proceeds by providing some experimental results, since this model has been fitted to data on a cross sectional basis for 41 census tracts in the Munich metropolitan area. The results obtained so far could be supportive to more detailed epidemiological studies of air pollution which have been conducted in many industrial countries; unfortunately, only relatively few have been conducted in West Germany. 相似文献
130.
Hans Freudenthal 《Die Naturwissenschaften》1963,50(6):199-205