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31.
We review published studies to show that changes in soil moisture levels have significant impacts on a range of wading bird species that use UK lowland grassland, including wet grassland, and obtain their food predominantly by probing the soil. We examine both the hydrological and the ecological literature and assess how management options could alter (1) ecosystem services (via water quality and flooding) and (2) habitat quality for wading birds. The combination of biodiversity goals with broader ecosystem services has been widely advocated and we suggest that appropriate management at multiple scales (e.g. small‐scale: ponds; large‐scale: integrated washlands) could potentially provide both ecosystem services and habitat for wading grassland birds. However, there is only a limited base of evidence on which to assess the potential linkage between these two areas, particularly for non‐wading bird species. Future work should be directed at identifying (1) how crop yield, ecosystem services and biodiversity relate to each other, (2) the extent of land needed to be managed to benefit these multiple purposes and bring about measurable gain (e.g. one or two ponds may make significant inroads in reducing run‐off and pollution but make little difference to wading birds) and (3) solutions to the challenges of setting up management options at large spatial scales (e.g. catchments).  相似文献   
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Aim To examine the effect of climate change on the occurrence and distribution of Pipistrellus nathusii (Nathusius’ pipistrelle) in the United Kingdom (UK). Location We modelled habitat and climatic associations of P. nathusii in the UK and applied this model to the species’ historical range in continental Europe. Methods A binomial logistic regression model was constructed relating the occurrence of P. nathusii to climate and habitat characteristics using historical species occurrence records (1940–2006) and CORINE land cover data. This model was applied to historical and projected climate data to examine changes in suitable range (1940–2080) of this species. We tested the predictive ability of the model with known records in the UK after 2006 and applied the model to the species’ known range in Europe. Results The distribution of P. nathusii was related positively to the area of water bodies, woodland and small areas of urbanization, and negatively related to the area of peat/heathland. Species records were associated with higher minimum temperatures, low seasonal variation in temperature and intermediate rainfall. We found that suitable areas have existed in the UK since the 1940s and that these have expanded. The model had high predictive power when applied to new records after 2006, with a correct classification rate of 70%, estimated by receiver operating characteristic analysis. Based on climate projections, our model suggests a potential twofold increase in the area suitable for P. nathusii in the UK by 2050. The single most influential climate variable contributing to range increase was the projected increase in minimum temperature. When applied to Europe, the model predictions had best predictive capability of known records in western areas of the species’ range, where P. nathusii is present during the winter. Main conclusions We show that a mobile, migratory species has adapted its range in response to recent climate change on a continental scale. We believe this may be the first study to demonstrate a case of range change linked to contemporary climate change in a mammal species in Europe.  相似文献   
33.
Iron--dioxygen-dependent changes to the biological activities of bleomycin   总被引:1,自引:0,他引:1  
Antitumor antibiotic bleomycin can bind to and degrade DNA, both in vivo and in vitro. This DNA damaging property in vitro can be related to its ability to chelate ferrous ions under aerobic conditions leading to the formation of "active oxygens," which are thought to be directly responsible for the damage. At present, evidence points to the hydroxyl radical formed by an iron-catalyzed Haber-Weiss reaction as the free radical most likely to be involved in this damage. When these same reactions occur in the absence of DNA, the free radicals then damage the bleomycin molecule, resulting in changes to its DNA-degrading activity, antibacterial properties, and chemical composition. Attempts to protect both bleomycin and DNA with a variety of specific and nonspecific scavengers have been unsuccessful, with several even showing pro-oxidant activity towards the iron-dependent damage. Only the metal chelators were effective inhibitors of bleomycin-iron-dependent damage to DNA. The damaged bleomycin lost some 50% of its ability to degrade DNA in vitro. This activity was closely paralleled by a loss in antibacterial activity against two different strains of bacteria.  相似文献   
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The aim of the present study was to see if positive attitudes toward animals can be predicted by the personality traits of agreeableness and conscientiousness, and whether higher levels of militaristic interests may lead to less positive attitudes. Militarism was expected to be predicted by lower agreeableness and conscientiousness, higher extraversion, and lower age. Known relationships between gender, age, and personality were also expected. These relationships were examined cross-culturally through a comparison between Cyprus and the UK, using measures translated for use in a Greek Cypriot sample and a new measure specifically designed for use in both UK and Cyprus samples. Cyprus, while similar to the UK in terms of its standard of living, retains a more traditional, rural lifestyle most often associated with collectivist cultures. While this study does not examine individualism and collectivism, findings may inform on any possible differences between such societies and offer a basis for more in-depth research. An online questionnaire was completed by 618 people and a path analysis was used to analyze the data, pooling the data for the analysis to determine possible cross-cultural causes for the observed differences in attitudes, personality traits, and interests. Findings indicated that individuals scoring high on agreeableness, scoring high on conscientiousness, Cypriot residents, females, and individuals expressing fewer militaristic interests expressed more positive attitudes toward animals. Additional relationships between personality, militaristic interests, and demographics were also established. The findings lend support to existing theory regarding the variables of interest and highlight significant new findings for the field. Cypriot residents reporting more positive attitudes toward animals may be a result of their collectivist culture, which appears to extend to human–animal relationships. New findings are discussed in light of suggestions for future research in the collectivist nature of Cypriot culture and its potential effects on militaristic interests and general animal welfare.  相似文献   
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Within the context of global competition for human talent, two policy shifts in favour of the promotion of high-skilled immigration (HSI) were observed in the UK and France during the 2000s. In light of similar policy inputs, this article compares the development and implementation of the British Highly Skilled Immigration Programme between 2002 and 2008 and the French Carte de Competences et Talents (Card of Competences and Talents) from 2006 to 2009. This research explores whether there was an overall convergence across these two European countries' policies towards HSI and if they have conformed to a similar client politics model. Whereas this politics model was identified in the UK, a policy gap was observed in France. This article relates the identified divergences with the political agency of the British and French policymakers, while the conclusions argue that politics trumped policy in the two selected cases.  相似文献   
38.
This review is based on a study commissioned by the European Commission on the evaluation of scientific, technical and institutional challenges, priorities and bottlenecks for biotechnologies and regional harmonisation of biosafety in Africa. Biotechnology was considered within four domains: agricultural biotechnologies (‘Green’), industrial biotechnologies and biotechnologies for environmental remediation (‘White’), biotechnologies in aquaculture (‘Blue’) and biotechnologies for healthcare (‘Red’). An important consideration was the decline in partnerships between the EU and developing countries because of the original public antipathy to some green biotechnologies, particularly genetically modified organisms (GMOs) and food from GM crops in Europe. The study focus reported here was West Africa (Ghana, Senegal, Mali and Burkina Faso).The overall conclusion was that whereas high-quality research was proceeding in the countries visited, funding is not sustained and there is little evidence of practical application of biotechnology and benefit to farmers and the wider community. Research and development that was being carried out on genetically modified crop varieties was concentrating on improving food security and therefore unlikely to have significant impact on EU markets and consumers. However, there is much non-controversial green biotechnology such as molecular diagnostics for plant and animal disease and marker-assisted selection for breeding that has great potential application. Regarding white biotechnology, it is currently occupying only a very small industrial niche in West Africa, basically in the sole sector of the production of liquid biofuels (i.e., bio-ethanol) from indigenous and locally planted biomass (very often non-food crops). The presence of diffused small-scale fish production is the basis to develop and apply new (Blue) aquaculture technologies and, where the research conditions and the production sector can permit, to increase this type of production and the economy of this depressed areas. However, the problems bound to environmental protection must not be forgotten; priority should be given to monitor the risks of introduction of foreign species. Red biotechnologies potentially bring a vast domain of powerful tools and processes to achieve better human health, most notably improved diagnostics by molecular techniques, better targeting of pathogens and a better knowledge of their sensitivities to drugs to permit better treatment.Biosafety regulatory frameworks had been initiated in several countries, starting with primary biosafety law. However, disparate attitudes to the purpose of biosafety regulation (e.g., fostering informed decision-making versus ‘giving the green-light for a flood of GMOs’) currently prevent a needed consensus for sub-regional harmonisation. To date, most R&D funding has come from North America with some commercial interests from Asia, but African biotechnology workers expressed strong desire for (re-)engagement with interested parties from the European Union. Although in some of the visited countries there are very well qualified personnel in molecular biology and biosafety/regulation, the main message received is that human resources and capacity building in-house are still needed. This could be achieved through home-based courses and capacity-building including funds for post-degree research to motivate and retain trained staff.  相似文献   
39.
Benthic foraminiferal assemblages in subrecent deposits are commonly used to reconstruct past sea level. Interpretations are generally made by comparison with either modern dead or total (live plus dead) assemblages. In both cases there will have been post-mortem changes that have differentially affected preservation. It is therefore important to establish the primary ecological controls by analysis of the living assemblages. We have determined the spatial and temporal variability of intertidal benthic foraminifera in the surface (0–1 cm) sediments from a time series survey of 31 sampling stations at Cowpen Marsh, for a period of 12 months. We counted 112,067 live foraminifera assigned to 28 species. The fauna was dominated by two agglutinated species (Jadammina macrescens and Trochammina inflata) on the high and middle marshes, and three calcareous species (Elphidium williamsoni, Haynesina germanica and Quinqueloculina spp.) on the low marsh and tidal flat.The standing crop of the whole intertidal zone, including the high, middle, low marsh and tidal flat habitats, and the individual species varied both temporally and spatially. The standing crop of the intertidal zone as a whole was greatest in the summer months and showed a positive correlation with elevation. The standing crops of the high and middle marshes showed similar temporal variation with peaks in summer and autumn and a trough in winter. The low marsh showed numerous peaks and troughs of standing crop during the year, whereas the tidal flat showed a single peak in summer. The standing crops of Jadammina macrescens and Trochammina inflata on the high and middle marshes peaked from April to May and August to October with troughs in winter. These agglutinated species showed a strong correlation with elevation. Haynesina germanica peaked in May to August and November to January on the low marsh, whereas on the tidal flat there was a single peak in July. The standing crops of E. williamsoni on the low marsh and tidal flat were relatively high in June and May, and July, respectively. Quinqueloculina spp. peaked in May to July on the low marsh and July on the tidal flat. The species was also found in the middle marsh from July to May and high marsh from September to November. Haynesina germanica showed a strong negative correlation with elevation, whereas the other two dominant calcareous species demonstrated weak negative correlations with both elevation and salinity.Reconstructing former sea level depends primarily on the recognition of high and middle marsh assemblages and in this study these are shown to be strongly controlled by elevation rather than salinity. Caution may be needed in interpreting low marsh and tidal flat data as salinity plays a more important role here.  相似文献   
40.
马蕊  严国泰 《生物信息学》2019,26(3):105-109
梳理了近200年英国乡村景观价值认知的发展脉络,分析了三次价值认知转变下,英国乡村景观保护的发展历程。借鉴英国乡村景观保护与发展的经验和方法,提出实现我国的乡村振兴离不开乡村多元价值的协调和多功能的融合、乡村景观特征的维系、乡村景观资源的协同管理以及乡村社区居民的参与四个途径的联合作用。  相似文献   
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