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721.
Parker J. Banks Matthew S. Tata Patrick J. Bennett Allison B. Sekuler Aaron J. Gruber 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(1):181-197
Gambling studies have described a “near-miss effect” wherein the experience of almost winning increases gambling persistence. The near-miss has been proposed to inflate the value of preceding actions through its perceptual similarity to wins. We demonstrate here, however, that it acts as a conditioned stimulus to positively or negatively influence valuation, dependent on reward expectation and cognitive engagement. When subjects are asked to choose between two simulated slot machines, near-misses increase valuation of machines with a low payout rate, whereas they decrease valuation of high payout machines. This contextual effect impairs decisions and persists regardless of manipulations to outcome feedback or financial incentive provided for good performance. It is consistent with proposals that near-misses cause frustration when wins are expected, and we propose that it increases choice stochasticity and overrides avoidance of low-valued options. Intriguingly, the near-miss effect disappears when subjects are required to explicitly value machines by placing bets, rather than choosing between them. We propose that this task increases cognitive engagement and recruits participation of brain regions involved in cognitive processing, causing inhibition of otherwise dominant systems of decision-making. Our results reveal that only implicit, rather than explicit strategies of decision-making are affected by near-misses, and that the brain can fluidly shift between these strategies according to task demands. 相似文献
722.
Although the rate of posttraumatic stress disorder (PTSD) among survivors of child maltreatment is high, individuals differ in symptom severity and many do not experience clinically significant levels of psychopathology. The present study tested the indirect effects of child maltreatment severity on adult PTSD, suicidal ideations, and alcohol dependence via anxiety sensitivity. A sample of 336 participants (mean age of 22.81 years, SD = 8.93; 70.2% female) completed an online survey of child abuse and neglect, anxiety sensitivity, PTSD symptom severity, suicidal ideation severity, and alcohol dependence severity. The results revealed significant indirect effects of child maltreatment on PTSD symptom severity through cognitive and social concerns, but not physical concerns. No direct or indirect effects were demonstrated for suicidal ideations or alcohol dependence severity. These findings elucidate mechanisms in the robust relationship between child maltreatment and adult PTSD symptoms and can potentially inform future research on mechanisms of change in psychotherapy. 相似文献
723.
Jens Jetzkowitz C.S.A. van Koppen Rolf Lidskog Konrad Ott Lieske Voget-Kleschin Catherine Mei Ling Wong 《Innovation: The European Journal of Social Science Research》2018,31(1):S38-S60
The term “biodiversity” is often used to describe phenomena of nature, which can be studied without a reference to the socially constructed, evaluative, or indeed normative contexts. In our paper, we challenge this conception by focusing particularly on methodological aspects of biodiversity research. We thereby engage with the idea of interdisciplinary biodiversity research as a scientific approach directed at the recognition and management of contemporary society in its ecological embedding. By doing this, we explore how research on and assessments of biodiversity can be enhanced if meaning, aspiration, desires, and related aspects of agency are methodically taken into account. In six sections, we substantiate our claim that the discourse on biodiversity (including the IPBES (Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services) debate) is incomplete without contributions from the social sciences and humanities. In the introduction, a brief overview of biodiversity’s conceptual history is provided showing that “biodiversity” is a lexical invention intended to create a strong political momentum. However, that does not impede its usability as a research concept. Section 2 examines the origins of the Convention on Biological Diversity (CBD) by way of sociological discourse analysis. Subsequently, it proposes a matrix as a means to structure the ambiguities and tensions inherent in the CBD. The matrix reemphasizes our main thesis regarding the need to bring social and ethical expertise to the biodiversity discourse. In Section 3, we offer a brief sketch of the different methods of the natural and social sciences as well as ethics. This lays the groundwork for our Section 4, which explains and illustrates what social sciences and ethics can contribute to biodiversity research. Section 5 turns from research to politics and argues that biodiversity governance necessitates deliberative discourses in which participation of lay people plays an important role. Section 6 provides our conclusions. 相似文献
724.
Patrícia Layne Alves Klebber Teodomiro Martins Formiga Marco Antônio Borges Traldi 《Urban Ecosystems》2018,21(4):697-706
Afforestation is inserted in the urban environment and interferes directly in the surface runoff. In order to quantify the rainfall interception by tree species, an experiment was carried out in the city of Uruaçu, Goiás, Brazil, with the four most common tree species in the urban afforestation of the region. The species chosen were the Mangifera indica (mango tree), the Caesalpinia peltophoroides (sibipiruna tree), the Pachira aquatica (munguba tree) and the Licania tomentosa (oiti). In order to register precipitation, ten pluviographs were used. They are capable of measuring precipitation over time in terms of duration, volume, and intensity. For events with a mean cumulative precipitation of 16.7 mm, the mean values of interception found in each species were: Mangifera indica - 8.0 mm; Pachira aquatica - 7.4 mm; Licania tomentosa - 7.2 mm; and Caesalpinia peltophoroides - 4.8 mm. The research confirms the importance of studies related to the identification of the species’ individual characteristics that interfere in the rainfall interception capacity and that can consequently contribute to urban drainage actions. In addition, it proves the existence of variations of rainfall interception in relation to rainfall events and during their occurrences and emphasizes the need for a careful definition of the species that will compose the urban afforestation. 相似文献
725.
Alien squirrels may seriously threaten native species by means of interspecific competition. In our work, we analysed whether the distribution of alien Siberian chipmunks within the Sigurtà Garden urban park (north-eastern Italy) changed after the natural spread of native Eurasian red squirrels in a 20-year period. Distribution of both squirrels was estimated through a citizen-science approach, in the first 10-year after red squirrel arrival 1 (i.e. Decade 1: 1997–2006) and in the second 10-year interval (i.e. Decade 2: 2007–2017). We compared habitat use of both species and we assessed whether a vertical segregation occurred through a dissimilarity index. Woodlands were selected by both species in both decades. Red squirrels also selected tree lines in Decade 1. A vertical segregation was apparent in Decade 1, whereas in Decade 2 both squirrel species were observed on the lowest branches or on the ground, where they are fed by humans. This was also confirmed by the habitat niche-overlap index, which increased in Decade 2. The extent of occurrence of Sciurus vulgaris increased throughout the park, whereas those of Eutamias sibiricus decreased. Differently from what is usually observed with alien squirrels, the spread of the native species appears to be halting and reversing the expansion of the non-native one. 相似文献
726.
Behavioural adaptations are recognized as crucial determinants for successful establishment and persistence of animal populations in a novel urban environment. Here, we examined mechanisms responsible for the development of urban behavioural type in a common waterbird, the Eurasian coot Fulica atra. We compared the behaviour of coots from a rural population and two urban populations that differed in the timing of colonization event (1960s vs. 2000s). We found that some behavioural characters associated with urban life (aggression during nest defence and boldness towards humans during foraging) were more strongly expressed in the older urban population when compared with the recently established urban population. By contrast, coots from the two urban populations showed a similar likelihood of exploiting human-derived food resources, as well as they showed similar levels of physiological stress. Urban coots were generally more aggressive, bolder, and less stressed than their rural conspecifics. Large behavioural and physiological divergence of coots from the recently established urban population and their rural conspecifics suggested that phenotypic plasticity and phenotype sorting may play a key role in the initial stages of urban colonization. On the other hand, increasing expression of boldness and aggression with the time since urbanization may suggest the role of microevolutionary adaptation in response to novel selective forces associated with the urban environment. Our results indicate that a combination of different processes (phenotypic plasticity, phenotype sorting, and microevolution) can determine successful colonization of urban areas by the Eurasian coots, and possibly other bird species. 相似文献
727.
Aaron C. Weinschenk Costas Panagopoulos Karly Drabot Sander van der Linden 《Social Influence》2018,13(2):53-64
In this paper, we re-analyze data from a large-scale field experiment (N = 344,084) on voter turnout in order to determine whether men and women respond differently to social pressure aimed at voter mobilization. To date, there have been mixed results regarding the interaction between a person’s gender and receptivity to social influence. On the whole, our analyses confirm prior findings that social pressure increases voter turnout but uncover little to no evidence of gender differences in receptivity to social pressure cues in the context of political participation. 相似文献
728.
This paper examines the short and medium term impact of early childcare provision by grandparents and formal care settings on child cognitive outcomes, using data from the Millennium Cohort Study (UK). Compared with children placed in formal childcare, children cared for by their grandparents are better at naming objects, but perform worse on tests of basic concept development and non-verbal reasoning. These results mask strong heterogeneities. On the one hand, the positive association between grandparental care and child outcomes is stronger for children from more advantaged households; on the other, the negative association is only significant for those from more disadvantaged households. The results of OLS estimations used for our analysis are confirmed using panel methods and an instrumental variable approach. 相似文献
729.
Yeon Jeong Son 《Review of Economics of the Household》2018,16(3):713-735
In response to a low fertility rate, a number of municipalities in South Korea have been providing family benefits in the form of childbirth grants and child allowances. Using panel data for 230 municipalities that spans the years 2001–2014, this paper examines the impacts of family benefits on the fertility rate in Korea. I use the fact that different municipalities began providing the family benefits at different times to estimate the impact of family benefits on fertility rates using a difference-in-differences approach. This study finds a positive effect of family benefits on total fertility rate. Moreover, it finds little evidence of an anticipatory response within municipalities that adopted the policy. Given that a 10 million Korean won increase in family benefits is associated with a 3.5% increase in the total fertility rate, an increase in family benefits of about 44 million Korean won per child would be required to raise the total fertility rate to a safe zone above 1.5 children per woman, where population declines are gradual and easily reversed. 相似文献
730.
Xiaoyan Lei Yan Shen James P. Smith Guangsu Zhou 《Review of Economics of the Household》2018,16(1):75-95
This research uses nationally representative data to study how economic resources and inequalities are associated with life satisfaction of Chinese residents. We construct economic resource and inequality measures from expenditure rather than from income, after confirming that expenditure inequality is a better measure in the Chinese context. We find that economic inequalities in general are negatively associated with life satisfaction, and that this association is larger for inequalities in the lower half of the distribution than those in the upper half of the distribution. We further explore the mechanisms under which inequality can be associated with life satisfaction, and find that aspiration is potentially one important channel. 相似文献