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OBJECTIVE: This November 2003 pilot study investigates the correlation between serum IgE and residential endotoxin levels from a group of 18 pregnant women living in Trujillo, Peru, and investigates the impact of the demographic and lifestyle factors of this group on the IgE and endotoxin levels measured. METHODS: Serum samples were collected from 19 subjects and analyzed for IgE. Dust samples were collected from the mattresses of 18 subjects and measured for endotoxin levels. A questionnaire was used to obtain demographic, socioeconomic, and lifestyle information for each subject. RESULTS: Geometric means for IgE and endotoxin were 246.8 (GSD=4.3, n=19) IU/mL and 66.5 EU/mg (GSD=1.7, n=18), respectively. Log-transformed IgE and endotoxin were not correlated (R2=0.02; p=0.60). CONCLUSIONS: Residential endotoxin and serum IgE were not correlated in this group. Potential selection bias and sample size are major limitations of the study. However, 74% (14/19) of the subjects in this study had an IgE over 100 IU/mL, a level generally considered elevated.  相似文献   
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Taking field margins out of intensive cultivation is a common form of agri-environmental scheme and on-farm nature management. Typically, no nutrients or pesticides are applied in these margins, which may be sown either with a crop or with grasses and native flowering plants. In some cases the margins are mown, while in others they are left alone. Newly established grass margins are less species-rich than field boundaries or road verges with a long history, justifying the expectation that field margins, if properly managed and given time and appropriate seed sources, could develop into relatively species-rich vegetation. We studied the biodiversity of both margins taken out of production and adjacent ditch banks in the years following initial establishment of the margins. To this end we combined the data of three different projects in order to increase the sensitivity of the statistical analyses. The results showed that the plant species richness of the field margins increased in the years following establishment over a period of four years. In addition, shifts in species composition indicated a decrease in soil nitrate concentrations. The species richness of both butterflies and dragonflies may increase. The most striking result was the marked increase in the plant species richness of the adjacent ditch banks in the five years following creation of the margins. Here, too, changes in species composition indicated a decrease in soil nitrate. In the years following establishment of the field margins there was no increase in the cover of agriculturally harmful weeds in these margins. However, the number of harmful nematodes increased. Our results show the short term effect of establishing field margins. Long term effects are still in need for further research.  相似文献   
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In the European Union (EU), waste management is almost totally regulated by EU directives, which supply a framework for national regulations. The main target in view of sustainability is the prevention of direct disposal of reactive waste in landfills. The tools to comply with these principles are recycling and material recovery as well as waste incineration with energy recovery for final inertization. The adaptation of the principles laid down in EU directives is an ongoing process. A number of countries have already enacted respective national regulations and their realization shows that recycling and incineration are not in competition but are both essential parts of integrated waste management systems. In the EU, the amount of residual waste available for energy recovery can supply approximately 1% of the primary energy demand. About 50% of the energy inventory of municipal solid waste (MSW) in most EU countries is of biogenic origin, and MSW is to the same extent to be looked upon as regenerative fuel. Hence part of the CO2 released from waste incineration is climate neutral. In the EU, this share could produce savings of the order of 1% of annual CO2 emissions if energy from MSW replaced that derived from fossil fuel.  相似文献   
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In a case of fetal anaemia due to pure red cell anaemia (Blackfan-Diamond syndrome), two-dimensional fetal Doppler echocardiography revealed an altered blood flow velocity pattern with entire incorporation of the atrial contraction component in the early passive filling phase of the right ventricle. Intracardiac blood velocities were increased, whereas cardiac output was only moderately increased. The fetal heart rate was normal. It is concluded that in fetal anaemia the compensatory mechanisms are limited and restricted to an increase in stroke volume. The hypothesis that chronic fetal anaemia is associated with ‘high output cardiac failure’ corresponds well with the present findings. The technique described may prove to be useful in the early diagnosis of fetal anaemia.  相似文献   
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‘Integration’ was one of the most frequently used words at the San Feliu Euroconference but the participants did not always use it in the same way. Integration is one of the key notions discussed in the subsequent papers bySalz, Green &; Penning-Rowsell, Köhn &; Gowdy andDavos. A short introduction to these papers is presented, where some of the views expressed by the authors are compared with related conceptions which can be found in social sciences literature.  相似文献   
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In the carbon capture and storage (CCS) chain, transport and storage set different requirements for the composition of the gas stream mainly containing carbon dioxide (CO2). Currently, there is a lack of standards to define the required quality for CO2 pipelines. This study investigates and recommends likely maximum allowable concentrations of impurities in the CO2 for safe transportation in pipelines. The focus is on CO2 streams from pre-combustion processes. Among the issues addressed are safety and toxicity limits, compression work, hydrate formation, corrosion and free water formation, including the cross-effect of H2S and H2O and of H2O and CH4.  相似文献   
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Community gardens vary in several ways: they are cultivated by different kinds of communities in various locations, entail individual or communal plots and the extent of active participation (e.g. gardening) differs. In this paper, we study seven community gardens with varying organisational designs and objectives, and investigate the extent to which these influence the enhancement of social cohesion. We also take into account to what extent differences in motivation among community gardeners matter. Despite these differences in motivation, however, we find that in all of the cases studied, people talk to and get to know others, and mutual help is widespread. We, therefore, conclude that community gardens contribute to the development of social cohesion – even if people are not particularly driven by social motivations. Moreover, while participants who are motivated by the social aspects of gardening naturally show a higher level of appreciation for them, these social aspects also bring added value for those participants who are motivated primarily by growing vegetables.  相似文献   
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