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451.
Urban policymakers and sustainable food activists have identified urban agriculture as an important strategy for confronting a host of urban problems, including food insecurity, health disparities, access to urban green space and community economic revitalisation. Much recent work on urban agriculture has examined community and school gardens, but little research has been undertaken on home gardens as a solution to urban problems. This article examines a home-gardening programme in San Jose, California, La Mesa Verde, asking whether some of the benefits found in community gardens can be found in home gardens. Specifically, we look at financial, health and community benefits, examining the potential of home gardens to become forces for broader social change. We ask whether gardens can become agents of cultural preservation, self-determination, particularly for recent immigrants who use these spaces to build identities and work towards collective action and self-determination.  相似文献   
452.
The aim of this paper is to presents a progress report on how a subnational jurisdiction, the Australian state of Victoria, is attempting to implement regional governance for sustainability through its catchment planning framework. The paper examines the lessons learnt from a best practice approach to the implementation of network governance to see whether there are actions that can be taken to improve regional governance for sustainability in Victoria. The authors argue that Victoria is implementing a network governance approach to natural resource management (NRM) as a significant component of sustainability and that this has certain advantages. In particular the emergence of Regional Catchment Strategies developed by the State's ten statutory Catchment Management Authorities as 'regional sustainability blueprints' is bringing a significant level of maturity to the state's governance framework. Furthermore the state is currently working to complete its governance for sustainability through new statewide integrating frameworks—an Environmental Sustainability Framework as well as a statewide Catchment Management and Investment Framework. The paper concludes that taking a network governance approach could have transformative potential but there are significant challenges ahead: the complex task of aligning of national, state, catchment and local government strategies through an outcomes focus; the scarcity of mechanisms and tools to assist in translation of strategies into integrated investment priorities; gaps in knowledge and understanding of natural resource management problems; limitations in the capacity of regional and local bodies, including local government; and getting the policy tools right within the framework. However, as the best practice examples illustrate, taking a gradual approach to the development of the institutions—building on successive wins in capacity—is the best and only way to proceed.  相似文献   
453.
ABSTRACT

Public schools are more than educational institutions; they are essential to creating liveable neighbourhoods. Despite their importance, public schools are being permanently closed across North America, and particularly in the Canadian province of Ontario. In 2015, one of Ontario's public school boards made the decision to permanently close the province's oldest public high school, located in the urban core of the historic midsized city of Kingston. While the school is not scheduled to close until late 2019, the established fate of this prominent public asset has important consequences for the liveability of Kingston's urban core. Accordingly, the objective of this study was to document residents’ perceived impacts of the decision to close to Kingston Collegiate Vocational Institute (KCVI) on liveability in the school's catchment area. We observed widespread dissatisfaction with the decision to close KCVI (85%), with large proportions of respondents (above 40%) anticipating KCVI's closure to negatively impact neighbourhood liveability in various ways in the future. Approximately one-quarter of respondents indicated that they have considered moving as a result of the decision, and among these, concerns about negative impacts to household-level well-being were particularly acute. Given the socio-demographic profile of respondents who have considered moving, these findings suggest that the closure of KCVI could have a destabilising effect on the neighbourhoods within the KCVI catchment area by driving families out of the city's urban core. Our findings suggest that policies to address concerns of under-enrolment are short-sighted and undermine efforts of other sectors to promote liveable communities.  相似文献   
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Tentacles of the sea anemone, Nematostella vectensis, are covered with hair bundles. Hair bundles were deflected by water jets to test whether they are mechanoreceptors. Electrophysiological recordings confirm that deflections of hair bundles induce transients in membrane current. In a different species of anemone, hair bundle mechanoreceptors are known to change shape and responsiveness according to the activity of chemoreceptors that bind prey-derived compounds including N-acetylated sugars. In Nematostella, hair bundles significantly elongate upon exposure to NANA, an N-acetylated sugar. Based on a bioassay in which discharged nematocysts are counted in gelatin-coated test probes touched to tentacles, we find that NANA shifts vibration dependent discharge of basitrich nematocysts to lower frequencies overlapping those produced during swimming by known prey including planktonic crustaceans. Furthermore, we find for the first time that vibration detection extends at least 2.5 cm beyond the tentacle tips. Thus, Nematostella likely employs its hair bundles to detect swimming movements of nearby prey.  相似文献   
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Foodborne viruses are a common and, probably, the most under-recognized cause of outbreaks of gastroenteritis. Among the main foods involved in the transmission of human enteric viruses are mollusks, and fruits and vegetables irrigated with wastewater and/or washed with non-potable water or contaminated by contact with surfaces or hands of the infected personnel during its preparation. In this study, 134 food samples were analyzed for the detection of Norovirus, Rotavirus, and Hepatitis A virus (HAV) by amplification of conserved regions of these viruses. From the 134 analyzed samples, 14 were positive for HAV, 6 for Norovirus, and 11 for Rotavirus. This is the first report in Mexico where emphasis is given to the presence of HAV and Norovirus on perishable foods and food from fisheries, as well as Rotavirus on frozen vegetables, confirming the role of vegetables and bivalve mollusks as transmitting vehicles of enteric viruses.  相似文献   
460.
Urban public spaces are important areas for leisure, recreation and physical activity and therefore contribute to the quality of life in cities. In particular, for adolescents they provide important spaces to meet with their peers, away from parental or school control. In many cities worldwide, public spaces have undergone severe developmental processes, and often a withdrawal from public space is noted. With regard to the opportunities those spaces provide for adolescents, it is necessary to investigate their current meaning for adolescents in a leisure context. In this article, qualitative research methods were used to investigate factors affecting adolescents’ use of public spaces in Vienna, Austria. In total 45 adolescents were interviewed. Results show that public open spaces are not regarded as important leisure spaces, and data reveal a strong retreat to private areas for leisure purposes. Perceived insecurities and fears support these processes and often result in avoidance of public spaces but also the wish for more control by authorities.  相似文献   
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