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Gene therapy provides a mutation-independent approach to treat or even cure CF airway disease. To develop a clinical candidate for CF gene therapy, a thorough examination of preclinical efficacy in relevant cell and animal models is a prerequisite. For a long time, the CF field was struggling with a lack of appropriate animal models for CF airway pathology. Since 2008, many different and complementary animal models have been generated that develop hallmarks of CF airway disease, including the CF pig, ferret, and rat. With this, a new era has arisen that allows investigating the efficacy of gene therapy beyond molecular and electrophysiological end-points. Successful gene therapy most likely requires an appropriate time window. CF lung pathology progresses with age and therefore an early treatment would be beneficial to prevent irreversible damage. In that regard, newborn screening programs and prenatal diagnosis already provide a basis to facilitate future preventive gene-based treatment. If successful, gene therapy for CF airway disease would markedly reduce the treatment burden and improve life quality and life expectancy of CF patients.  相似文献   
107.
Few urban environmental stewardship, or civic ecology, practices monitor their impacts on local communities and ecosystems. This lack of monitoring prevents lay stewards from adapting their practices based on outcomes. For those that do collect data on their practices, we see different forms of practitioner engagement in outcomes monitoring. We categorise these different forms of engagement according to five published models of public participation in scientific research, revealing different strategies for collecting and analysing data towards adaptive co-management in urban ecosystems. We propose two broad strategies for expanding outcomes monitoring in these contexts: creating openly accessible tools and protocols for do-it-yourself inquiry and supporting more resource-intensive partnerships between practitioners and scientists for more complex forms of outcomes monitoring.  相似文献   
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Human actions towards land, freshwater and oceans have already caused biodiversity to decline. This study aims to investigate attitudes towards the conservation of biological biodiversity among different groups in a Swedish city, Kristianstad. An inquiry including statements measuring attitudes towards the conservation of habitats, animals and plants, to the biological diversity within selected local areas, to global and national areas, and to societal issues, was replied to by 271 persons. Deciduous forests, birds and wild flowers were given highest priority. An area categorized as wetland including lakeshore meadows with a rich bird life was prioritized as most important for conservation while a forest area was chosen as best for recreation. The experts gave lower priority to arable land, urban parks, domestic animals, agricultural and garden plants and to conifer forests compared to the other groups. Knowledge about what people in general value as important could facilitate the future planning of nature areas in the city of Kristianstad.  相似文献   
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Water Consumption in the Production of Ethanol and Petroleum Gasoline   总被引:1,自引:0,他引:1  
We assessed current water consumption during liquid fuel production, evaluating major steps of fuel lifecycle for five fuel pathways: bioethanol from corn, bioethanol from cellulosic feedstocks, gasoline from U.S. conventional crude obtained from onshore wells, gasoline from Saudi Arabian crude, and gasoline from Canadian oil sands. Our analysis revealed that the amount of irrigation water used to grow biofuel feedstocks varies significantly from one region to another and that water consumption for biofuel production varies with processing technology. In oil exploration and production, water consumption depends on the source and location of crude, the recovery technology, and the amount of produced water re-injected for oil recovery. Our results also indicate that crop irrigation is the most important factor determining water consumption in the production of corn ethanol. Nearly 70% of U.S. corn used for ethanol is produced in regions where 10–17 liters of water are consumed to produce one liter of ethanol. Ethanol production plants are less water intensive and there is a downward trend in water consumption. Water requirements for switchgrass ethanol production vary from 1.9 to 9.8 liters for each liter of ethanol produced. We found that water is consumed at a rate of 2.8–6.6 liters for each liter of gasoline produced for more than 90% of crude oil obtained from conventional onshore sources in the U.S. and more than half of crude oil imported from Saudi Arabia. For more than 55% of crude oil from Canadian oil sands, about 5.2 liters of water are consumed for each liter of gasoline produced. Our analysis highlighted the vital importance of water management during the feedstock production and conversion stage of the fuel lifecycle.  相似文献   
110.
Concern over nonpoint source P losses from agricultural lands to surface waters in frigid climates has focused attention on the role of freezing and thawing on P loss from catch crops (cover crops). This study evaluated the effect of freezing and thawing on the fate of P in bare soils, soils mixed with dairy manure, and soils with an established catch crop of annual ryegrass (Lolium multiflorum L.). Experiments were conducted to evaluate changes in P runoff from packed soil boxes (100 by 20 by 5 cm) and P leaching from intact soil columns (30 cm deep). Before freezing and thawing, total P (TP) in runoff from catch-cropped soils was lower than from manured and bare soils due to lower erosion. Repeated freezing and thawing significantly increased water-extractable P (WEP) from catch crop biomass and resulted in significantly elevated concentrations of dissolved P in runoff (9.7 mg L(-1)) compared with manured (0.18 mg L(-1)) and bare soils (0.14 mg L(-1)). Catch crop WEP was strongly correlated with the number of freeze-thaw cycles. Freezing and thawing did not change the WEP of soils mixed with manures, nor were differences observed in subsurface losses of P between catch-cropped and bare soils before or after manure application. This study illustrates the trade-offs of establishing catch crops in frigid climates, which can enhance P uptake by biomass and reduce erosion potential but increase dissolved P runoff.  相似文献   
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