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Chronic degenerative lung diseases are essentially untreatable pathological conditions. By contrast, the healthy lung has numerous mechanisms that allow for rapid repair and restoration of function following minor acute injuries. We discuss the normal endogenous processes of lung development, homeostatic maintenance and repair and consider the research strategies required for the development of methods for human therapeutic lung regeneration. 相似文献
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J. M. Medlock A. G. C. Vaux K. M. Hansford M. E. Pietzsch E. L. Gillingham 《Medical and veterinary entomology》2020,34(2):175-183
The present study aimed to assess whether agri-environment field margins provide a habitat for the sheep/deer tick Ixodes ricinus. Field studies were conducted in arable farmland in southern England in both extant and newly constructed field margins. The presence and intensity (i.e. the mean number of nymphs per transect, excluding zeros) of questing nymphs and adult I. ricinus were compared between field margins with three adjacent habitats: woodland, hedgerow and arable land. The presence and intensity of ticks within a field margin was also compared between three ecozones: the ecotone, the margin and the crop. It was found that field margins do support I. ricinus, although the intensity of ticks was associated with field margins with adjacent woodland, with a higher tick intensity along the ecotonal ecozone, compared with the rest of the margin or the crop edge. The presence of a hedge also increased the likelihood of finding questing nymphs in a field margin compared with a margin adjacent to arable land. This effect, however, was less pronounced than in field margins with adjacent woodland. The provision of footpaths within the margin (at least 1–2 m from the ecotone), or on the edge of the crop where paths run next to woodland known to be an important tick habitat, could be promoted to minimize tick exposure. In addition, based on the results of the present study, raising awareness that walking alongside woodlands also constitutes a tick risk could be promoted. 相似文献
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Reduced-effort schemes for monitoring butterfly populations 总被引:4,自引:0,他引:4
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Luis Gabriel Carmona Kai Whiting Helmut Haberl Tnia Sousa 《Journal of Industrial Ecology》2021,25(1):125-143
Energy and material flows and material stocks are key requirements for the supply of goods and services, which in turn support societal development. However, most resource accounting methods restrict the analysis to resource flows, which fails to acknowledge the increasing role of in‐use stocks in service provision. Using the UK transport sector as a case study, we undertook a material flow analysis through the lens of the stock–flow–service (SFS) nexus. We used the latter to identify how steel consumption and accumulation in vehicles contributed to passenger mobility between 1960 and 2015. Our results show that the efficiency of the steel stock contained in cars and motorcycles decreased from 37.5 to 28.0 passenger‐km (pkm)/kg‐year. The steel service for buses decreased from 63.6 to 32.1 pkm/kg‐year, while that of the national railway increased from 23.8 to 70.3 pkm/kg‐year steel. London Underground steel stock–service efficiency improved from 31.5 to 57.0 pkm/kg‐year steel. The annual fraction of flows that maintained the steel stock varied according to vehicle category and was between 3.4% and 8.2%. In terms of the stock expansion rate, the greatest change (on average, an annual increase of 3%) was that of “cars and motorcycles.” This reflects the demographic transitions and the growing consumer demand for car‐based mobility. We discussed how the SFS nexus contributes to a more comprehensive form of resource accounting and reflect upon some of its limitations and how they might be addressed. 相似文献