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861.
The geographies of the current generation of young people are markedly distinct from previous generations by virtue of their access to a virtual playground. The vast majority of young people now engage in video gaming as a leisure activity. Drawing on findings from the 2009/2010 WHO Health Behaviour in School-aged Children study this paper set out to investigate the factors that might be associated with higher levels of video gaming. Information was collected from 4404 school students aged 11, 13 and 15 years, using anonymised self-completed questionnaires. Higher usage was defined as game play exceeding two hours a day. Separate analyses were conducted for boys and girls. For both genders higher levels of game playing was associated with early adolescence, opposite sex friends and minimal parental mediation. Bullying and going to bed hungry were associated with higher usage for boys only, while life satisfaction and family activities were linked to girls’ game playing only. Parents were identified as effective mediators of young people’s video game usage. The study identified gendered motivations for higher levels of game play, suggesting different interventions for boys and girls may be required in order for young people to create a balanced approach to video gaming.  相似文献   
862.
Urbanization has been identified as a threat to biodiversity due to landscape modifications. Studies of parasite ecology in urbanized areas lagged behind those made on macro organisms. Here we studied infection prevalence of haemosporidian parasites in an avian community of an urban forest from Germany, and its relationship with bird abundance and body mass. We used PCR to amplify a fragment of the mtDNA cyt b gene to determine the infection status of birds, and bird point counts to determine bird relative abundances. The avifauna was dominated by two small sized insectivore passerines (Parus major, Cyanistes caeruleus), representing ~40 % of the total bird records. The highest haemosporidian prevalence was recorded for Turdus philomelos (100 %) and for Fringilla coelebs (75 %). Bird abundance and body mass were positively associated with infection status for two haemosporidian genera: Plasmodium and Leucocytozoon. Infection rate was lower in juveniles compared to adult birds. We recorded a total of 7 Plasmodium, 26 Haemoproteus, and 10 Leucocytozoon lineages. Avian malaria (P. relictum) was detected infecting 5 individuals of P. major, the most abundant species in the community. These results, together with those of previous studies at the same site, suggest that potentially any of the genetic haemosporidian lineages detected in this urban forest can be transmitted across native and pet bird species, and to species of conservation concern housed at aviaries.  相似文献   
863.
Tropical forested ecosystems provide multiple ecosystem services to rural and urban landscapes, with carbon storage gaining particular attention. Deforestation due to rural-urban transitions may lead to a reduction in carbon storage ability. Coastal mangrove forests are particularly at risk from deforestation due to their location in the rapidly urbanizing coastal zone, and the city state of Singapore is an extreme example, losing as much as 90 % of its original mangrove cover due to land reclamation and reservoir construction. Knowledge of mangrove ecosystem services may allow better conservation, restoration and incorporation of remaining mangrove patches into the urban landscape. Focusing on the regulating ecosystem service of carbon storage, mangrove carbon stocks have been estimated for Singapore using a combination of field and remote sensing techniques. Biomass carbon showed substantial spatial variation, with old, contiguous mangrove patches containing a higher density of biomass carbon than fragmented, river-fringing or restored mangroves. In total, national biomass carbon equated to 116,117.1 megagrams of carbon (Mg C), and a coarse estimate of the total carbon stock (including soil carbon) suggests that Singapore’s mangroves may store 450,571.7 Mg C. While lower than other regional estimates focused on natural, oceanic mangroves, this is a significant carbon stock for a disturbed, urban mangrove system, and may be equivalent to the average annual carbon emissions of 621,000 residents. This analysis, alongside a review of other urban forest studies, highlights the importance of forested ecosystems such as mangroves in providing a carbon storage ecosystem service to urban areas.  相似文献   
864.
Species that successfully inhabit urban ecosystems are rare, and urbanisation often drives localised extinctions of native species. Nonetheless, some species take advantage of the novel conditions available in cities and increase in abundance. Trends in the abundance and distribution of species in urban areas have received much attention, but the precise elements of urban ecosystems that affect the survival of urban-dwelling species are largely unknown. Animals that successfully exploit urban environments may do so because of increases in the availability of resources or habitats. Here we assess the effects of anthropogenic landscapes and prey abundance on the persistence of an orb-weaving spider, Nephila plumipes. We assessed spider persistence for six months in situ along an urban gradient in Sydney. We then transplanted spiders from a common garden into sites along the gradient, monitored their persistence in the new environment and measured a suite of environmental variables at local and landscape scales. The abundance of prey was closely linked with spider persistence, in both the survey and the transplant experiment, and was positively associated with anthropogenic habitats. The surveyed spiders survived longer when located closer to the coast and transplanted spiders persisted longer in smaller sites with more impervious surfaces and reduced vegetation cover. Our study shows that urbanisation has a strong effect on potential prey abundance and can lead to increased persistence of N. plumipes, demonstrating the broad impacts that habitat disturbance can have on the life history and trophic interactions of city-dwelling animals.  相似文献   
865.
This paper explores how online actions such as the practice of digital self-writing shape our offline identity. We start with an examination of the concept of hupomnemata – a practice of self-writing in which notes are kept as a ‘material record of things read, heard, or thought’ in the intent of shaping the self [Foucault (1997). Self writing. In P. Rabinow (Ed.), Ethics, subjectivity and truth. The essential works of Foucault, 1954–1984. Volume 1 (pp. 207–222). New York, NY: The New Press p. 209] – before arguing that the practice of digital content curation can be understood as a modern-day variant of the Greco-Roman hupomnemata. Although the work of the digital curator is conducted online, this paper positions contemporary curatorial practices as acts of self-exploration, self-cultivation, and self-care, which nourish offline identity and which ultimately work to shape the offline, corporeal self.  相似文献   
866.
The objective of this research is to investigate the possible difference in accumulation of adversity over the life course among decedent gamblers and living control gamblers in the province of Quebec, Canada. A sample of 90 adult men, 41 living participants and 49 suicide decedents, met the criteria for at-risk and problem gambling over the last five years. Data were obtained from informants in the case of suicide and directly from living controls during semi-structured face-to-face interviews using SCID I and II, SOGS, Module K and a recount of life trajectories methodology. The results showed a high level of adversity throughout the life trajectories of both groups. However, the living gamblers faced more difficulties during their lifespan than the suicide victims. In the last six months before their death, suicide victims had a significantly higher number of mental health disorders, especially co-morbid mental health disorders and anxiety, compared to the living controls. We also observed a rapid escalation of difficulties, more life events and more psychological distress in the last six months of their lives among the suicide decedents. Suicidal behaviour needs to be carefully investigated by medical staff and mental health practitioners, especially when gamblers demonstrate evidence of mental health disorders or financial difficulties.  相似文献   
867.
This paper draws upon international research evidence that suggests a relationship between protest masculinity and the manifestation of violent crime among young males, and that criminal desistance may be linked to (inter-) subjective processes such as the reconstruction of masculine identity. The paper considers the potential that pugilism (the art and practice of boxing) may have on enabling young, disadvantaged minority male gang members to find avenues for alternative identity construction and to gain transitional experiences which trigger self-confessed desistance actions. Drawing upon an ethnographic study conducted in a boxing rehabilitation centre on the outskirts of Copenhagen, Denmark, the paper reports on data gleaned from participant observation and qualitative interviews with 22 ethnic minority young men. Findings suggest that the masculine context within the rehabilitation programme provided the young men with a safe space to perform broader versions of locally dominated views on masculinity and to reflect on their current situations and dilemmas. The young men were clearly in transition and their desistance journeys were characterized by hope and ambition but also disappointment and despair. In some cases it appeared that the young men's dogged attempts to desist from crime became a new way for them to ‘do masculinity’. The authors draw upon the findings to make recommendations for policy, practice and research.  相似文献   
868.
This study addresses the gap in the research for sound multidimensional assessment of social capital and its relationship with risk-taking behaviour among youths living in disadvantaged communities. Social capital and adolescent risk-taking outcomes were studied cross-sectionally in 1371 secondary students living in two disadvantaged communities within Australia. First, a multidimensional measure of social capital was developed and tested using confirmatory factor analysis. Then, the associations between social capital and a range of youth risk-taking behaviours were examined using structural equation modelling across five-year groups (Grades 7–12). With a few exceptions, higher levels of social capital and belongingness within the school and community were generally associated with decreases in smoking, alcohol and drug consumption, and physical violence. Some outcomes were more strongly associated with family and peer social capital, while others associated more with neighbour and community social capital, indicating that attempts to build social capital need to be targeted across the whole community. This study supports the notion that social capital can be measured empirically and is beneficial in alleviating many of the detrimental health outcomes commonly associated with risk-taking behaviours during adolescence.  相似文献   
869.
This study examines three-year post-baseline outcomes for a randomized controlled trial of Swedish antisocial youths who received either multidimensional treatment foster care (MTFC) or treatment as usual (TAU). Several studies in our literature review indicated that MTFC intervention is preferred to the alternative (TAU) in the USA during follow-up. Two studies (one conducted in the UK and one in Sweden) have shown indications of a washout effect between the intervention alternatives during follow-up. However, this study showed few but positive significant outcomes at follow-up for the MTFC programme in comparison to TAU. Juveniles who participated in MTFC spent fewer days in locked settings and had committed fewer violent crimes, according to the social case records. Two key features of the MTFC programme certainly merit use in general social service—namely, reducing exposure to deviant peers and increasing school participation.  相似文献   
870.
Silicon Valley, California – home of Apple, Facebook, Twitter, Google, and so on – is widely regarded as the epicentre of the information revolution. However, it is not just a technical or economic phenomenon; it has also made a social revolution. The article evaluates Silicon Valley from a normative perspective, seeking to identify its real societal impact, negative as well as positive. A select review of significant literature is followed by exposition of primary data, based on in situ face-to-face interviews with Valley occupants; these range from the chief technology officer of a global brand to a homeless, unemployed Vietnam War veteran. The article organises its findings under three headings: the nature of information revolution; iCapitalism as a new technoeconomic synthesis; and the normative crisis of the information society. It concludes with a warning about ongoing attempts to clone Silicon Valley around the world.  相似文献   
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