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971.
972.
ABSTRACT

Geographic mobility is increasingly perceived worldwide as a key to academic excellence, career advancement and upward social mobility. Drawing on long-term qualitative fieldwork data, this paper interrogates the impact of academic mobility in reconfiguring class and gender identities among students, early professionals and their families from Hong Kong and Indonesia who have studied or received further training in Germany, the Netherlands and the USA. This analysis problematises the crude ‘academic mobility?→?upward social mobility’ formula and considers international academic mobility as a contextual, dynamic and multi-directional process. Through this process social positions and identities of the moving individuals and families are negotiated in an on-going manner as migrants insert into, depart from and re-insert into the various social milieus where their mobility trajectories touch ground. Narratives of interviewees illustrate the complexity and contradictions in class and gender configurations as students move across borders. They show how these individuals are inserted in contrasting social positionings, and experience how a particular social class or gender position carries different connotations. The paper concludes with a few conceptual and methodological reflections.  相似文献   
973.
ABSTRACT

Applying the science of human factors to eliminate error across all aspects of process design, management, operation, and maintenance has been a focus in the process safety area for many years. Human error has been attributed as a major cause of many high profile catastrophic accidents around the world. These accidents have resulted in national and international attention, which has led to a focus on improving organizational capabilities, systems, and in many cases, governmental regulations around human factors. This article provides a review of the field of human factors highlighting various topics in the literature, and introduces governmental regulatory bodies currently engaging organizations in a scientific approach to human factors. Finally, the need for integrating behavioral science methodologies with human factors is addressed. This is done with specific focus on how Organizational Behavior Management methodologies can work in concert with human factors to optimize process safety.  相似文献   
974.
For an integer \(k \ge 1\), a distance k-dominating set of a connected graph G is a set S of vertices of G such that every vertex of V(G) is at distance at most k from some vertex of S. The distance k-domination number \(\gamma _k(G)\) of G is the minimum cardinality of a distance k-dominating set of G. In this paper, we establish an upper bound on the distance k-domination number of a graph in terms of its order, minimum degree and maximum degree. We prove that for \(k \ge 2\), if G is a connected graph with minimum degree \(\delta \ge 2\) and maximum degree \(\Delta \) and of order \(n \ge \Delta + k - 1\), then \(\gamma _k(G) \le \frac{n + \delta - \Delta }{\delta + k - 1}\). This result improves existing known results.  相似文献   
975.
Communicating the rationale for allocating resources to manage policy priorities and their risks is challenging. Here, we demonstrate that environmental risks have diverse attributes and locales in their effects that may drive disproportionate responses among citizens. When 2,065 survey participants deployed summary information and their own understanding to assess 12 policy‐level environmental risks singularly, their assessment differed from a prior expert assessment. However, participants provided rankings similar to those of experts when these same 12 risks were considered as a group, allowing comparison between the different risks. Following this, when individuals were shown the prior expert assessment of this portfolio, they expressed a moderate level of confidence with the combined expert analysis. These are important findings for the comprehension of policy risks that may be subject to augmentation by climate change, their representation alongside other threats within national risk assessments, and interpretations of agency for public risk management by citizens and others.  相似文献   
976.
This study examined the impact of five domains of social support (a campus group for individuals who identify as a sexual minority, family, friends, significant others, and faith communities) on eight aspects of sexual minority identity development (identity uncertainty, internalized homonegativity, identity affirmation, acceptance concerns, identity superiority, concealment motivation, identity centrality, and difficulty in the identity development process). Support from a sexuality-specific campus group was the strongest predictor, followed by support from family members. Supports from friends and significant others had no significant impact on any aspect of sexual minority identity development, while faith community support was not correlated with identity development. Identifying as lesbian, bisexual, or as another sexual minority compared to identifying as gay also impacted sexual minority identity development.  相似文献   
977.
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   
978.
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   
979.
Constructed wetlands in urban environments may be used by urban amphibian populations for breeding. Yet, few studies have examined the performance of young-of-the-year from created wetlands even though the success of terrestrial life stages is directly linked to the performance of individuals at the egg and larval stage. We assessed how early-stage amphibians developing within constructed stormwater wetlands compared in body size (one metric of performance) to those in nearby natural wetlands. We conducted surveys for wood frog, Lithobates sylvaticus, larvae and young-of-the-year metamorphs at 13 wetlands located in the City of Edmonton, Alberta, Canada and compared metamorph size (a useful metric for fitness and reproductive success) between constructed stormwater and two types of natural wetlands. We related body size to within-wetland parameters (reflecting water chemistry, thermal regimes and physical characteristics) and used an information-theoretic approach to identify predictors of metamorph body size. Abundances of egg masses, larvae and metamorphs were generally lower at stormwater than natural wetlands. Metamorphs exhibited larger body size in stormwater wetlands compared to natural wetlands. Low metamorph abundances and cool, stable water temperatures best explained large body size in stormwater metamorphs. We propose that with increasing urbanization and associated construction of artificial wetlands, size benefits in early developmental stages may help individuals cope with reduced habitat suitability in the terrestrial environment.  相似文献   
980.
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   
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