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The aim of this study was to investigate hepatitis A virus (HAV), hepatitis E (HEV), and rotavirus (RV) in fresh and processed meat traded on the border of Brazil with Argentina and Uruguay. In total, 159 samples of raw and processed foods of animal origin were collected in Paso de los Libres, Argentina (n?=?53 raw meat, n?=?24 processed meat) and Rivera, Uruguay (n?=?55 raw meat, n?=?18 processed meat), or were seized by the Brazilian International Agricultural Surveillance System—VIGIAGRO (Brazil–Argentina border) (n?=?8 raw meat, n?=?1 bush meat). All samples were tested for the presence of HAV, HEV, and RV genomes. HAV genes were detected in 18.23% of samples and RV genes in 23.89%. No HEV-positive samples were detected. HAV was also detected in two of the VIGIAGRO samples. Processed meats from Argentina and Uruguay had a higher rate of HAV and RV than raw meat (P?>?0.05). The median HAV in the Argentinian and Uruguayan samples was 6.9?×?104 and 3.5?×?103 copies/g, respectively. The presence of RV viral genes in raw meats from Argentina was significant, and this was not observed in processed meats. The presence of HAV and RV genes in a significant portion of products from Argentina and Uruguay is a potential source of human infection. This also indicates precarious conditions of acquisition, processing, and manipulation, which could be improved by improved regulation of food across borders.  相似文献   
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Mainstream literature on climate change concentrates overwhelmingly on technological solutions for this global long-term problem, while a change towards climate-friendly behaviour could play a role in emission reduction and has received little attention. This paper focuses on the potential climate mitigation by behavioural change in the European Union (EU) covering many behavioural options in food, mobility and housing demand which do not require any personal up-front investment. We use the Global Change Assessment Model (GCAM), capturing both their direct and indirect implications in terms of greenhouse gas emissions. Our results indicate that modest to rigorous behavioural change could reduce per capita footprint emissions by 6 to 16%, out of which one fourth will take place outside the EU, predominantly by reducing land use change. The domestic emission savings would contribute to reduce the costs of achieving the internationally agreed climate goal of the EU by 13.5 to 30%. Moreover, many of these options would also yield co-benefits such as monetary savings, positive health impacts or animal wellbeing. These results imply the need for policymakers to focus on climate education and awareness programs more seriously and strategically, making use of the multiple co-benefits related with adopting pro-environmental behaviour. Apart from that, the relevance of behavioural change in climate change mitigation implies that policy-informing models on climate change should include behavioural change as a complement or partial alternative to technological change.  相似文献   
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Pollinators search for multiple flora resources throughout their life cycle. Most studies, however, only assess how bees discriminate floral cues in the context of nectar foraging. In the present study, we sought to elucidate whether oil-collecting bees discriminate flowers of Byrsonima variabilis (Malpighiaceae) with petals of different colours when foraging for pollen or oil. As the colour of the standard petal changes during anthesis, we characterised the spectral reflectance patterns of flowers throughout anthesis and modelled chromatic perceptual space to determine how these colour patterns are perceived by bees. Through the quantification of flower pollen in the different phases, we found that the colour of the standard petal is an honest cue of the presence of pollen. Centridine bees preferentially visited flowers with a yellow (bee’s green) colour when searching for pollen, but indiscriminately visited flowers with different petal colours when searching for floral oil. We suggest that standard petals, in the species studied and others of the genus, like nectar guides, act as pollen guides, which oil-collecting females use to detect pollen-rich flowers. Moreover, they use different floral clues during foraging for different resources in the same host plant.  相似文献   
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Choices have to be made to manage invasive species because eradication often is not possible. Both ecological and social factors have to be considered to improve the efficiency of management plans. We conducted a social study on Fallopia spp., a major invasive plant taxon in Europe, including (1) a survey on the perception of a landscape containing Fallopia spp. using a photoquestionnaire and (2) an analysis of the social representations of Fallopia spp. of managers and users in one highly invaded area and one less invaded area. The respondents to the photoquestionnaire survey appreciated the esthetics of the landscapes less when tall Fallopia spp. were present. Few people were able to identify and name the plant, and this knowledge negatively affected the appreciation of the photos containing Fallopia spp. The central core of the social representation of Fallopia spp. was composed of the invasive status of the plant, its density, and its ecological impacts. The peripheral elements of the representation depended on the people surveyed. The users highlighted the natural aspect whereas the managers identified the need for control. In the invaded area, the managers qualified the species as “unmanageable,” whereas the species was qualified as “foreign” in the less invaded area. Those results provide insights that have to be included when objectives of management plans of these species are selected.  相似文献   
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This paper examines the challenge of achieving a balance between the implementation of centrally designed pro-poor policies and the decentralization of responsibilities to local governments in many African countries. It analyzes the implementation of the Rural Water Supply and Sanitation Program in Tanzania. Key mechanisms for planning and allocating resources are analyzed at ministry, district, and village levels. Results show that a mixture of policy incoherencies, technical shortcomings and political influence determine that only a small proportion of funds reaches the underserved areas. We argue that a greater connection between the bottom-up and top-down planning mechanisms, and a sharp increase of downwards accountability are needed before decentralized decision-making result in better resources allocation. Meanwhile a bigger intervention from central government is needed.  相似文献   
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