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BACKGROUND: Mold growth is believed to be one causative factor underlying the association between dampness in buildings and increased respiratory morbidity. Measurements of beta(1-->3)-glucans and fungal extracellular polysaccharides (EPS) are used as markers of mold exposure in field studies. Little is known about their levels and determinants in homes. OBJECTIVE: To study levels and determinants of beta(1-->3)-glucan and EPS levels in mattress and living room floor dust in three European countries. METHODS: Mattress and living room floor dust was collected in the homes of 1065 German, Dutch, and Swedish (pre-)school children. All samples were analyzed for beta(1-->3)-glucans and EPS in one central laboratory. Determinants were assessed by questionnaire. RESULTS: Amounts of dust, EPS and beta(1-->3)-glucan levels differed between countries. Amounts of dust, beta(1-->3)-glucan and EPS levels for mattresses were only weakly correlated with those for living room floors. Floor dust beta(1-->3)-glucan loads, EPS loads and EPS concentrations were strongly correlated with the amount of dust sampled, which is largely determined by the type of floor that was sampled (carpeted floors had 5-20 higher amounts of dust). None of the other determinants was consistently and statistically significantly associated with amounts of dust, beta(1-->3)-glucan and EPS concentrations on floors and mattresses. CONCLUSION: Mattress dust and floor dust are two different measures of exposure to the investigated mold components. Living room floor beta(1-->3)-glucan and EPS loads and EPS concentrations are largely determined by the type of floor sampled. Differences between countries can only partly be explained by the determinants studied.  相似文献   
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Typhoon Haiyan struck the Philippines on 8 November 2013 with maximum sustained winds of 235 kilometres per hour, adversely affecting at least 11 million people and displacing some 673,000 in the central regions of the country. The disaster clearly overwhelmed the Philippine government despite its seemingly well‐crafted disaster management plan. Using timelines of different organisations, this paper identifies gaps in the government's response, mainly due to its failure in coordinating and managing relief operations, which adversely affected its effectiveness and efficiency in the delivery of critical goods and services following the disaster. The paper also demonstrates how non‐governmental organisations (NGOs), the United Nations, foreign governments and other organisations provided assistance, mainly through aid niching, to cover the government's shortcomings. The paper recommends a paradigm shift in the government's disaster response by integrating collaborative arrangements between government agencies and NGOs, and giving local governments the lead role, with the national government as support, in disaster planning and response.  相似文献   
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Fleischer S 《Ambio》2003,32(1):2-5
Evidence is provided for an internal CO2 sink in forest soils, that may have a potential impact on the global CO2-budget. Lowered CO2 fraction in the soil atmosphere, and thus lowered CO2 release to the aboveground atmosphere, is indicated in high N-deposition areas. Also at forest edges, especially of spruce forest, where additional N-deposition has occurred, the soil CO2 is lowered, and the gradient increases into the closed forest. Over the last three decades the capacity of the forest soil to maintain the internal sink process has been limited to a cumulative supply of approximately 1000 and 1500 kg N ha(-1). Beyond this limit the internal soil CO2 sink becomes an additional CO2 source, together with nitrogen leaching. This stage of "nitrogen saturation" is still uncommon in closed forests in southern Scandinavia, however, it occurs in exposed forest edges which receive high atmospheric N-deposition. The soil CO2 gradient, which originally increases from the edge towards the closed forest, becomes reversed.  相似文献   
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Zusammenfassung  Polychlorierte aromatische Kohlenwasserstoffe (PHAK), z.B. 2,3,7,8-Tetrachlordibenzo-p-dioxin (TCDD), weisen eine Vielzahl von toxischen Wirkungen und biologischen Effekten auf. Die Substanzklasse der PHAK besitzt die Eigenschaft der Bindung an ein cytosolisches Rezeptor-Protein, gefolgt von der Synthese bestimmter Genprodukte, u.a. von Cytochrom P450 1A1 (CYP 1A1). In dieser Arbeit wird ein Bioassay beschrieben, der erlaubt, die Induktion von CYP 1A1 als Summenparameter für die biologische Wirksamkeit der kritischen, halogenierten Verbindungen in komplexen Umweltmatrizes zu bestimmen. Zur Abtrennung von Substanzen aus den Extrakten von Umweltproben (z. B. Naturstoffe und polyzyklische aromatische Kohlenwasserstoffe), die den Bioassay st?ren k?nnen, wurde ein Ein-S?ulen-Clean-up entwickelt. Die biologisch ermittelten TEQ-Werte stimmen gut mit den Resultaten der chemischen Analytik überein. Der Bioassay in Kombination mit dem Clean-up bietet eine zeitsparende und kostengünstige M?glichkeit zur Untersuchung von Umweltproben.   相似文献   
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This article describes a biomonitoring using mosses in order to determine the amount and distribution of the atmospheric deposition of 37 elements in the European region of the Neisse river following the political and economic changes. These results are compared with the findings in other regions. Additionally, the accumulation characteristics ofPleurozium schreberi andPolytrichum formosum, the two moss species used in the study, were compared with one another. Until the beginning of the 1990s, this region was part of the socalled “black triangle”, an area characterised by extremely high atmospheric dust pollution. Through the closing of numerous factories, the equipment of power plants with filters, and the decreasing importance of brown coal as a source of household heating, the situation has changed considerably. Today, the pollution levels in the European region of the Neisse river are comparable with those in the western part of Germany. Higher levels were only determined for Fe and Ti, which can be attributed to the broader usage of brown coal as a source of energy. In the area around Katowice, Poland, the levels of certain elements were found to be more than ten times higher than in the European region of the Neisse. These highly elevated levels of atmospheric contamination in the industrial district of Upper Silesia indicate that action is urgently needed.  相似文献   
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Phosphorus loading from precipitation and more than a dozen tributaries of Big Beat Lake, Woman, was determined for the period from January to December 1978. Direct precipitation contributed 1120 kg·P·yr-1 (0.096 g P·m-2·yr-1) while tributary runoff contributed 21,560 kg for a total P loading of 1.84 g P·m-2 Rathbone creek, although accounting for only 4 percent of the hydro-logic input to Big Bear Lake, contributed >27 percent of the annual phosphorus load. Phosphorus loading increased with increased impervious geology and increased development. Nitrogen loading exhibited similar loading patterns. Big Beat Lake is currently eutrophic and is likely to remain eutrophic. Calculations based on Vollenweider's critical phosphorus loading concept indicated that tributary P-loading would have to be reduced by >95 percent to achieve mesotrophic conditions. The completion of Big Bear Dam created a “naturally” eutrophic re mix which dl require proper management to enhance its resource potential.  相似文献   
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