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1.
DevelopmentoftheprocedureforthestabilizationofrainwatersamplesYuanZhongxin;Chung-ShinYuan(DepartmentofChemicalEngineeringNati...  相似文献   

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On the study of ecosystem health:state of the art   总被引:2,自引:0,他引:2  
IntroductionDuringlastdecades,theterm“ecosystemhealth”isusedwithincreasingfrequencyintheliterature.Thegrowinginterestsinthestu...  相似文献   

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Objective

To explore the views and practices of maternal-fetal medicine specialists on offering fetoscopic endoluminal tracheal occlusion (FETO) for left- and right-sided congenital diaphragmatic hernia (LCDH, RCDH) in the post Tracheal Occlusion To Accelerate Lung growth (TOTAL)-trial era.

Method

Cross-sectional knowledge, attitude and practice survey was conducted among 105 attendees of the 19th World Congress of Fetal Medicine.

Results

On average, respondents were knowledgeable about CDH, involved in research, and provided antenatal treatment options. Four out of five (82%) agreed that neonatal survival in LCDH can be reliably predicted in the prenatal period. Few respondents considered the exact risks and benefits of FETO for severe LCDH as being unclear (16%), yet half were uncertain about this for moderate LCDH (57%) and severe RCDH (45%). Most respondents offer FETO for severe LCDH (97%) and RCDH (79%), but only 59% offer it for moderate LCDH. However, half of respondents (58%) stated that not offering FETO for moderate LCDH would be a psychological burden for parents.

Conclusion

Respondents consider the risk-benefit ratio of FETO for severe LCDH clear and consistently offer FETO, but not for moderate LDCH and severe RCDH. However, not offering the option of FETO to parents was considered a psychological burden.  相似文献   

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Central to the mission of America's environmental schools is the development of professional environmental managers. The majority of our graduate students at Yale are enrolled in our master of environmental management program. But what exactly is environmental management? When I am asked this question, I reply that environmental management is the new business of bringing our human enterprise into harmony with the natural world of which we are a part. And I add: it's the most important thing in the world.  相似文献   

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Based on the significant enhancement of fluorescence intensity of carbaryl in inclusion complex, a spetrofluorimetric method with high sensitivity was developed for the determination of carbaryl in aqueous solution. Under the optimum conditions, the complex had excitation and emission maxima at 278 nm and 332 nm, respectively. The linear range of the method was 7.0 ng/ml-1500 ng/ml with a detection limit of 1.2 ng/ml. The proposed method was successfully used to determine quantitatively of carbaryl in cottonseeds.  相似文献   

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Based on the significant enhancement of fluorescence intensity of carbaryl in inclusion complex, a spetrofluorimetdc method with high sensitivity was developed for the determination of carbaryl in aqueous solution. Under the optimum conditions, the complex had excitation and emission maxima at 278 nm and 332 nm, respectively. The linear range of the method was 7.0 ng/ml-1500 ng/ml with a detection limit of 1.2 ng/ml. The proposed method was successfully used to determine quantitativelv of carbarvl in cottonseeds.  相似文献   

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IntroductionNowweallconcernourselveswiththecontemporaryproblemsofoverpopulation,resourceexploitation,environmentalpollutionand...  相似文献   

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With the development of rural pollution, its characteristic and institutional factor should be studied for pollution control through economics and sociology. Based on the data gathered from investigations by several government sectors, rural environmental pollution can be divided into two types by its sources: internal source type and external source type. The internal source type is the main component of rural pollution at present, which can be further divided into three types. Research shows that the contributing institutional factors of rural pollution issues and the effectiveness of environmental management system over rural pollution can be summarized as distinctiveness. In essence, the rural pollution issue results from the dualism of rural and urban areas’ inadaptability to rural modernization. In detail, the contributing factors can be summed up on three institutional levels. There are obvious loopholes in rural environmental management system which, in the meantime, is incapable and inadaptable to rural pollution control. There exist similar questions in the related public service system, which are intensified by inappropriate reform which brought about incompatible incentive in the recent years. However, in the eleventh five-year plan period, there are advantageous trends in the three institutional levels. Main data sources in this paper: ➀ the surveys on TVEs (township and village enterprises) conducted by Township Enterprise Bureau of Ministry of Agriculture of China in 1997 and 2002; ➁ the partial survey on rural environmental conditions by EPA (environmental protection administration) of Zhejiang Province in 2002; ➂ the survey on the pollution of IPLFs (livestock and poultry farms) in 23 provinces, municipalities, and directly administered cities by the State Environmental Protection Administration of China in 2002; ➃ the research report on Mechanism of Investment and Financing for Environmental Protection by China Council for International Environment and Development Cooperation in 2003; ➄ the third investigation on national hygiene service in 2003; ➅ the regular monitoring of safe quality of agricultural products by the Ministry of Agriculture of China in 2005; ➆ the investigation arranged by the Ministry of Health which finished in 2007 and showed the total situation of rural environmental health and drinking water security of the whole country.  相似文献   

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OntheecologyofvectorsFernandoDiasdeAvilaPiresDepartmentofTropicalMedicine,InstitutoOswaldoCruz,21045900RiodeJaneir,BrazilAb...  相似文献   

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The World Year of Physics (2005) is an international celebration to commemorate the 100th anniversary of Einstein’s “Annus Mirabilis.” The United Nations has officially declared 2005 as the International Year of Physics. However, the impact of Einstein’s ideas was not restricted to physics. Among numerous other disciplines, Einstein also made significant and specific contributions to Earth Sciences. His geosciences-related letters, comments, and scientific articles are dispersed, not easily accessible, and are poorly known. The present review attempts to integrate them as a tribute to Einstein in commemoration of this centenary. These contributions can be classified into three basic areas: geodynamics, geological (planetary) catastrophism, and fluvial geomorphology. Regarding geodynamics, Einstein essentially supported Hapgood’s very controversial theory called Earth Crust Displacement. With respect to geological (planetary) catastrophism, it is shown how the ideas of Einstein about Velikovsky’s proposals evolved from 1946 to 1955. Finally, in relation to fluvial geodynamics, the review incorporates the elegant work in which Einstein explains the formation of meandering rivers. A general analysis of his contributions is also carried out from today’s perspective. Given the interdisciplinarity and implications of Einstein’s achievements to multiple fields of knowledge, we propose that the year 2005 serve, rather than to confine his universal figure within a specific scientific area, to broaden it for a better appreciation of this brilliant scientist in all of his dimensions.  相似文献   

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IntroductionOverpastten years,thestratosphericozonedepletionhasbeencontributedtotheactivechlorideandbromide(Harris,1995) .Althoughtheconcentrationofbromideismuchlessthanthatofchloride,theozonedepletionefficiencyofbromideis 50timesgreater (Harris,1995;McElroy ,1986)…  相似文献   

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TheU .S .EnvironmentalProtectionAgencyrequestedtheNationalResearchCouncil(whichistheoperatingarmoftheU .S .NationalAcademyofSciencesandtheU .S .NationalAcademyofEngineering)tocarryoutacriticalscientificevaluationofindicatorstomonitorecologicalchangesfromeit…  相似文献   

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AppljcationofthethermallenseffectfordeterminationofiodideGuXiaomei:WangShunrong;QinKexuan;Lijiechun(ResearchCenterforEco-Envi...  相似文献   

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The peculiar biogeography of the so-called Lost World, i.e. the summits of sandstone tableaux (tepuis) in the Neotropical Guyana region of Venezuela, has generated a debate regarding the factors that are thought to account for modern vegetation patterns in the region. Some argue that plant communities on these high-elevation summits reflect a long history of evolution in isolation, while others surmise that there has been substantial biotic interchange with the surrounding lowlands during glacial times. Until now, these apparently competing hypotheses have not been tested using palaeoecological methods. I used pollen analysis of Quaternary sediments and documented past vertical migrations of vegetation in response to climate changes, which supports the second hypothesis. Physiographical analysis, however, shows that about half the tableaux summits are too high for their flora to have reached the lowlands during the last glaciation, suggesting that a portion of the tableaux vegetation has always experienced some degree of biotic isolation. Thus, a component of the summit vegetation evolved in isolation, whereas other taxa experienced interchange, as reflected in endemism patterns among the tableaux summits. Biogeographical patterns on the summits are the result of complex evolutionary processes. The two hypotheses invoked to explain the vegetation patterns are not mutually exclusive, but instead complement one another.  相似文献   

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Dyes in wastewater are of particular environmental concern since they give an undesirable color to the waters, dye and their derivatives are harmful to human health and the environment ( Annadurai et al., 2002). Due to their biological persistency, conventional biological treat-ment processes such as activated sludge process are ineffective for their removal(Shaul et al., 1991). There is a need to develop effective methods for the degradation of such persistent organic pollutants, either to less harmful compounds or, more desirable, to their complete mineralization.  相似文献   

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The origin of the pygmy right whale (Caperea marginata) has long been one of the most vexing conundrums of marine mammal evolution. The extremely disparate skeletal structure of Caperea and a patchy fossil record have left morphology and molecules at odds: whereas most morphological analyses ally Caperea with right whales (Balaenidae), most molecular studies instead suggest a close relationship with rorquals (Balaenopteridae) and grey whales (Eschrichtiidae). The morphological evidence supporting a Caperea-balaenid clade consists of several shared features of the skull and mandible, as traditionally observed in adult individuals. Here, we show that at least two of these features, the ascending process of the maxilla and the coronoid process, arise from substantially different precursors early during ontogeny and therefore likely do not represent genuine synapomorphies. Both of these juvenile morphologies have adult counterparts in the fossil record, thus indicating that the ontogenetic variation in the living species may be a genuine reflection of differing ancestral states. This new evidence contradicts previous morphological hypotheses on the origins of Caperea and may help to reconcile morphological and molecular evidence.  相似文献   

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