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781.
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
782.
The environmental factors affecting the spatial dynamics of bird communities in urban parks are well understood, but much less attention has been paid to the seasonal dynamics of bird communities. Since migrant and resident human commensal birds might have contrasting responses to environmental factors of urban parks, we expected different seasonal dynamics among parks. On the other hand, because bird species can have different habitat relationships throughout the year, we also expected different responses of bird richness to environmental variables between breeding and non-breeding seasons. Bird surveys were conducted in 14 small urban parks (1–4 Ha) of Mar del Plata city (Argentina) for one full annual cycle. Bird richness changed between seasons, but bird abundance remained constant. Bird community composition did not vary between seasons, but urban parks near the urban center, with the highest pedestrian traffic and isolation to other green areas had the least seasonal change of composition. During the breeding season, bird richness was negatively affected by the percentage cover of high buildings surrounding the immediate limits of parks, whereas during the non-breeding season bird richness was not related with any environmental variable. Bird composition variation among parks was affected by the distance to the urban center during both seasons. Results showed that urbanization promotes a seasonal homogenization of bird communities in urban parks, probably by affecting the presence of migrant species and promoting the temporal stability of human commensal species. 相似文献
783.
Laura Castro‐Schilo Emilio Ferrer Maciel M. Hernández Rand D. Conger 《Journal of research on adolescence》2016,26(4):753-768
We used a longitudinal community study of 674 grade school children (Grades 5, 6, 7, and 8; 337 males, 337 females) of Mexican origin to examine outcomes of school attachment. Attachment to school is important in this population given the high level of school dropout rates of Mexican‐origin students. Results indicated that, on average, school attachment from fifth to sixth grade remains stable, but declines from sixth to eighth grade. Boys had lower levels of school attachment at fifth grade but followed similar patterns of change as girls did. Attachment to teachers, peer competence, school aspirations and expectations, and substance‐use cognitions emerged as longitudinal outcomes of level or changes in school attachment. Gender moderated associations of school attachment. 相似文献
784.
Rayna M. Sansanwal Jeffrey L. Derevensky Belle Gavriel-Fried 《International Gambling Studies》2016,16(1):67-84
Mental health professionals are well versed in addressing multiple adolescent risky behaviours and play a primary role in the identification of and referral process and service provision for young people who engage in such behaviours. Given their ‘person-in-environment’ approach, training in multi-sectoral collaboration, and awareness of social policies, social workers are especially equipped to provide needed mental health services to young people. The aim of the current study was to examine Israeli mental health professionals’ awareness of and attitudes towards adolescent high-risk behaviours, including gambling. Child psychologists, social workers and school counsellors (N = 273) completed an online survey addressing concerns related to high-risk behaviours. Findings revealed that social workers perceived gambling as being among one of the least concerning adolescent mental health issues and reported feeling the least confident in their abilities to provide services to young people with gambling problems. The results suggest the importance of youth gambling addictions being incorporated into social work training curricula. 相似文献
785.
Mélina Andronicos Guy Beauchamp Marie Robert Jacques Besson Monique Séguin 《International Gambling Studies》2016,16(1):140-155
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
786.
This study assessed social skills in post-institutionalized (PI) children with respect to age at adoption, age at assessment, and gender. Parent ratings of social skills (Social Skills Rating System) and behavior problems (Child Behavior Checklist) were obtained for 214 children and 127 adolescents who were adopted from socially-emotionally depriving Russian institutions. Results showed that children adopted before 18 months of age have better social skills than those adopted after this age; those assessed in childhood demonstrate better social skills than those assessed in adolescence. PI females, especially later-adopted adolescents, have particularly poor social skills. Children with poor social skills tend to have higher rates of behavior problems. 相似文献
787.
Cross-sectional research on internationally adopted children has indicated an association between early attachment disturbances and language deficits. Raaska et al. (2013) have speculated that this relationship is likely bidirectional. In an attempt to elucidate the causal relationship between these two risk factors, the attachment disturbances and language skills of 44 internationally adopted children were assessed in a cross-lagged structural equation model. Greater attachment disturbances at wave 1 predicted less gain in language by wave 2. In contrast, language at wave 1 was not predictive of attachment disturbances at wave 2. These results suggest that early attachment problems may present an important risk for later language development and should be an immediate and primary focus of post-adoptive intervention for families adopting internationally. 相似文献
788.
789.
Previous research suggests that parents may be less happy than non-parents. We critically assess the literature and examine parents’ and non-parents’ happiness-trends using the General Social Survey (N = 42,298) and DDB Lifestyle Survey (N = 75,237). We find that parents are becoming happier over time relative to non-parents, that non-parents’ happiness is declining absolutely, and that estimates of the parental happiness gap are sensitive to the time-period analyzed. These results are consistent across two datasets, most subgroups, and various specifications. Finally, we present evidence that suggests children appear to protect parents against social and economic forces that may be reducing happiness among non-parents. 相似文献
790.
Interaction with employees is essential for organizational leaders. If executives do not communicate well, important processes like giving feedback, setting goals or guiding change processes can nevertheless lead to resistance from subordinates when communication is received as more threatening than challenging. Conveying messages in ways that provoke challenge instead of threat appraisals can be achieved via employee-oriented communication, but this may require taking peoples’ differing motivational orientations into account. This is because motivational orientations partially determine what kind of information is motivating to us, which goals and strategies we prefer, and how we deal with changes. In this regard, Regulatory Focus Theory (Higgins 1997) compares the gain- and success-sensitive promoter with the loss- and failure-sensitive preventer. This article applies this theory to the organizational psychological context and outlines practical implications for managers. The goal of the piece is to provide managers a leadership tool that acknowledges the diversity of peoples’ motivational styles and by that revealing a need-oriented and more efficient way in communication with subordinates. 相似文献