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81.
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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Since at least 600 BC, cacao (Theobroma cacao L.) has occupied a place of cultural importance in Mesoamerica. In many Maya groups its importance as a ritual food plant is second only to maize (Zea mays L.). The Ch’orti’ Maya and their culturally non-indigenous Ladino neighbours in Eastern Guatemala continue to use cacao for culinary and ceremonial purposes. Of particular importance are cacao uses in Ch’orti’ rain ceremonies, which are strongly connected to local environmental knowledge. The protection of cacao as a sacred tree may help to limit slash-and-burn maize agriculture to sustainable levels.  相似文献   
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Traditional environmental knowledge (usually imparted orally) is being lost from many regions of the world, requiring novel forms of transmission if this situation is to be redressed. Loss of this knowledge may be a significant contributory factor towards ecological decline. Undoubtedly, disruption to ecosystems and societies that depend on these has impacted on traditional land management practices, with negative ramifications for biodiversity. From an environmental perspective, scientists in northern Australia need to understand traditional Aboriginal methods of ‘caring for country’, such as burning regimes, so that these can be incorporated into strategies today for maintaining Australia’s rich biodiversity. However, information exchange should be two-way: as well as learning from local people, science can in turn benefit people who may have little experience of, for example, invasive species. The challenge is how can the complexity of biological knowledge from within different ontologies be represented and integrated in a way that it can be of use to scientists and local people, in order to ensure a sustainable future? The main aim of this study was to record existing local knowledge of biodiversity for the community of Aurukun (far north Queensland), integrating this knowledge with scientific data, while giving parity to both knowledge systems and protecting intellectual property rights. A cross-cultural collaboration between community members and ethnobiologists resulted in development of the Aurukun Ethnobiology Database. An interdisciplinary approach was taken to effectively model autochthonous biological knowledge and scientific data to create a database with a number of practical applications.  相似文献   
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Since 2001 a real-time radiation monitoring network of Canadian nuclear facilities and major population centres has been implemented for response to nuclear incidents including a possible terrorist attack. Unshielded NaI(Tl) spectroscopic detectors are employed to measure gamma radiation from airborne radioactivity and radioactivity deposited on the ground. These detectors are composed of a standard 3'x3' cylindrical NaI(Tl) spectrometers with data storage and integrated telemetry. Some of the detectors have been deployed in the Ottawa Valley near Chalk River Laboratories and Ottawa, which has a complex radioxenon environment due to the proximity of nuclear power reactors, and medical isotope facilities. Although not a health threat, these releases have provided an opportunity for the Canadian Meteorological Centre and the Commissariat à l'Energie Atomique to validate their meteorological models. The meteorological models of the two organizations are in good agreement on the origin and the source terms of these releases.  相似文献   
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