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991.
Urbanization has been considered as a major threat to biodiversity, making its ecology of increasing interest. Many urban ecology studies have been developed in a short time-scale, measuring real-time patterns. However, long-term studies are imperative to understand the responses of some species to the urbanization process. In this study, we aimed to assess the information provided by a recent one-year citywide bird survey when compared to a published ‘historical’ bird list of a neotropical city (Xalapa, Mexico) that compiles information of the past three decades, mainly from urban greenspaces. Specifically, we contrasted species richness values and assessed differences in species composition between both lists. We recorded 51 species in the one-year citywide survey, representing ~15 % of those reported in the historical list. Nonetheless, the upper-bound confidence interval of the citywide survey richness prediction represented ~66 %. Most of the species recorded in the one-year citywide survey are insectivores and granivores, a pattern that agrees with previous findings that underline the importance of insectivores as part of urban bird communities in the Neotropics. Although we used robust methods to compare our one-year citywide bird list and the historical list for the city of Xalapa, we acknowledge the limitations of comparing them. However, our results shed some light on the kind and type of information that one-year citywide surveys can provide and the importance of long-term studies for comprehending the processes involved in biodiversity changes within urban areas over time. Undoubtedly, establishing long-term citywide surveys sampling birds and other biodiversity groups will allow us to better understand the response of biodiversity to urbanization over time. 相似文献
992.
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
993.
Sarah Bartos Smith Jenny E. McKay Jennifer K. Richardson Amy A. Shipley Michael T. Murphy 《Urban Ecosystems》2016,19(2):577-598
Urbanization poses threats to earth’s biota, and retention of remnant native habitat in protected areas within expanding urban boundaries may help alleviate threats to wildlife. However, it is unclear for nearly all nonsynanthropic (i.e., not benefiting from an association with humans) species whether vital rates in urban habitats can sustain populations or if populations persist only through immigration from outside the urban boundary. We conducted a three-year study of spotted towhees (Aves: Pipilo maculatus) breeding in four undeveloped parks in Portland, OR, USA, to measure park-specific seasonal reproductive output (F) and annual adult survival (SA). We developed a stochastic model that combined F and SA with an estimate of first-year survival to measure population growth rate (λ) in all parks assumed to be closed to immigration. F differed among parks but SA did not. Relatively high F was possible because many pairs raised >1 brood/season. When combined with empirical estimates of survival through the 30-day period of post-fledging parental care (SD = 0.645), only 2 of 4 parks were self-sustaining (i.e., λ > 1.0). However, SD reflected substantial loss of fledglings to domestic cats (Felis catus). Assuming no loss to cats and either partial compensatory or additive mortality of fledglings substantially improved prospects of population persistence for declining (sink) populations. Moreover, allowing low levels of immigration to sinks reversed population declines in most parks even when vital rates were insufficient to maintain populations. Our results suggest that nonsynanthropic bird species can persist in urban landscapes, but also that offspring mortality in the post-fledging period may be a critical determinant of population viability. 相似文献
994.
Katie Palmer du Preez Jason Landon Maria Bellringer Nick Garrett Max Abbott 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2016,32(4):1115-1126
In New Zealand a simple pop-up message feature that provides gambling session information and forces a break in play is mandatory on all electronic gaming machines in all venues (EGMs). Previous research has demonstrated small effects of more sophisticated pop-up messages tested predominantly in laboratory environments. The present research examined gambler engagement with and views on the New Zealand pop-up messages and on the relationship between pop-up messages and EGM expenditure. A sample of gamblers was recruited at casino and non-casino (pub) EGM venues. Most participants were aware of pop-up messages (57 %) and many saw them often (38 %). Among gamblers who reported seeing pop-up messages, half read the message content, and a quarter believed that pop-up messages helped them control the amount of money they spend on gambling. Participants who reported being likely to stop gambling in response to pop-up messages spent significantly less money on gambling when variables that were independently associated with EGM expenditure were controlled for. A modest harm minimisation effect of the pop-up message feature that has been operating in New Zealand for 5 years was evident. Suggestions for improvement of the harm minimisation potential of the current pop-up message feature are discussed. 相似文献
995.
Emma Botterill Peter Richard Gill Suzanne McLaren Rapson Gomez 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2016,32(3):1027-1038
Problem gambling rates in older adults have risen dramatically in recent years and require further investigation. Limited available research has suggested that social needs may motivate gambling and hence problem gambling in older adults. Un-partnered older adults may be at greater risk of problem gambling than those with a partner. The current study explored whether loneliness mediated the marital status–problem gambling relationship, and whether gender moderated the mediation model. It was hypothesised that the relationship between being un-partnered and higher levels of loneliness would be stronger for older men than older women. A community sample of Australian men (n = 92) and women (n = 91) gamblers aged from 60 to 90 years (M = 69.75, SD = 7.28) completed the UCLA Loneliness Scale and the Problem Gambling Severity Index. The results supported the moderated mediation model, with loneliness mediating the relationship between marital status and problem gambling for older men but not for older women. It appears that felt loneliness is an important predictor of problem gambling in older adults, and that meeting the social and emotional needs of un-partnered men is important. 相似文献
996.
Richard J. E. James Claire O’Malley Richard J. Tunney 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2016,32(4):1155-1173
Analyses of disordered gambling assessment data have indicated that commonly used screens appear to measure latent categories. This stands in contrast to the oft-held assumption that problem gambling is at the extreme of a continuum. To explore this further, we report a series of latent class analyses of a number of prevalent problem gambling assessments (PGSI, SOGS, DSM-IV Pathological Gambling based assessments) in nationally representative British surveys between 1999 and 2012, analysing data from nearly fifty thousand individuals. The analyses converged on a three class model in which the classes differed by problem gambling severity. This identified an initial class of gamblers showing minimal problems, a additional class predominantly endorsing indicators of preoccupation and loss chasing, and a third endorsing a range of disordered gambling criteria. However, there was considerable evidence to suggest that classes of intermediate and high severity disordered gamblers differed systematically in their responses to items related to loss of control, and not simply on the most ‘difficult’ items. It appeared that these differences were similar between assessments. An important exception to this was one set of DSM-IV criteria based analyses using a specific cutoff, which was also used in an analysis that identified an increase in UK problem gambling prevalence between 2007 and 2010. The results suggest that disordered gambling has a mixed latent structure, and that present assessments of problem gambling appear to converge on a broadly similar construct. 相似文献
997.
Transformational leaders are known to inspire and motivate their followers, thereby leading to enhanced job satisfaction. Job satisfaction is an intellectual concept regarding individuals’ attitudes toward their jobs. This study asserts that the underlying mechanisms for transformational leadership to affect employee satisfaction are trust in the community, including the leader (that is, organization) and trust in the self, namely self‐efficacy. Leadership is specifically associated with continual transformations in the higher educational context, and collectivist cultures may manifest different processes underlying the transformational leadership–satisfaction relationship. This study investigated the mediating effects of trust and self‐efficacy on the relationship between transformational leadership and job satisfaction. The study sample included academicians from a nonprofit higher education institution in Turkey. The data were analyzed using structural equation modeling. The results showed that the relationship between transformational leadership and job satisfaction is fully mediated by both trust and self‐efficacy. The mediator effect of trust was shown to be stronger than self‐efficacy, which is assumed to be the result of the cultural context. The results are discussed in the context of employee satisfaction and cultural determinants of employee satisfaction. 相似文献
998.
Natasha R. Magson Rhonda G. Craven Geoff Munns Alexander S. Yeung 《Journal of youth studies》2016,19(5):569-592
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
999.
Andres J. Vargas 《Review of Economics of the Household》2016,14(3):625-668
I use the American Time Use Survey from 2003 to 2012 to analyze, from a gender and marital status perspective, how the time Mexican immigrants devote to market work, household production, personal care, and leisure activities compare to the corresponding time allocations of US natives. Furthermore, I estimate the effect of duration of residence in the US on the immigrants overall patterns of time use. Time diary evidence indicates that, upon arrival to the US, Mexican immigrant men devote more time to market work and commuting than comparable non-Hispanic natives, regardless of their marital status. On the other hand, Mexican immigrant women devote the same amount of time to these activities as the non-Hispanic reference groups, irrespective of the marital status. In addition, the trend data show that immigrant men decrease their paid work with years since migration while immigrant women increase it. Estimates indicate that, for married immigrant men there is a tradeoff between market work and household work, whereas for single immigrant men the tradeoff is between market work and leisure. Finally, Mexican immigrant women relinquish mostly passive leisure and sleep time to meet demands of family and market work. 相似文献
1000.
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