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881.

Niche partitioning reduces interspecific competition, facilitating coexistence. In urban ecosystems, however, habitat loss reduces species’ ability to spatially partition activity. Temporal partitioning may thus increase in urban areas as species, unable to avoid each other spatially, partition time to avoid competition. In Midwestern US cities, eastern gray squirrels (Sciurus carolinensis) and fox squirrels (S. niger) co-occur and compete for resources. We identified urban gray and fox squirrel activity patterns and how they vary with season, land cover, and among sites where they do and do not co-occur using camera-trap data. Both species’ activity patterns varied with season and canopy and impervious surface cover. Gray squirrel activity patterns varied in the presence of fox squirrels only in the fall, providing limited support for our temporal partitioning hypothesis. Temporal niche partitioning may thus play a role in supporting these species co-existence when competition is seasonally-elevated (e.g., fall hording), but appears less important in other seasons.

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882.
883.
The bullwhip effect describes the tendency for the variance of orders in supply chains to increase as one moves upstream from consumer demand. We report on a set of laboratory experiments with a serial supply chain that tests behavioral causes of this phenomenon, in particular the possible influence of coordination risk. Coordination risk exists when individuals' decisions contribute to a collective outcome and the decision rules followed by each individual are not known with certainty, for example, where managers cannot be sure how their supply chain partners will behave. We conjecture that the existence of coordination risk may contribute to bullwhip behavior. We test this conjecture by controlling for environmental factors that lead to coordination risk and find these controls lead to a significant reduction in order oscillations and amplification. Next, we investigate a managerial intervention to reduce the bullwhip effect, inspired by our conjecture that coordination risk contributes to bullwhip behavior. Although the intervention, holding additional on‐hand inventory, does not change the existence of coordination risk, it reduces order oscillation and amplification by providing a buffer against the endogenous risk of coordination failure. We conclude that the magnitude of the bullwhip can be mitigated, but that its behavioral causes appear robust.  相似文献   
884.
This study examines young children's career aspirations, gender differences in those aspirations, and children's perceptions of the amount of math and science used in careers. We asked 1634 students in first to third grades what job they wanted in the future and how much they thought they would use math or science in it. Career aspirations were sorted into 27 career categories, of which 12 showed significant gender differences. Notably, boys were more likely to indicate military, manual labor, and math/computer science careers, and girls were more likely to indicate stay at home parent, education, and animal care careers. Students aspiring to science, technology, engineering, and mathematics (STEM) careers thought they would use science, but not math, more than non-STEM-aspiring students did. School counseling interventions focused on specific STEM subfields, and education highlighting links between school subjects and careers requirements may benefit students and reduce gender inequality in STEM fields.  相似文献   
885.
Early childbirth is common among young women ageing out of foster care and may impede their educational progress. However, few studies have explored access to postsecondary education among young mothers who have been in foster care. The present study used data from a large, national sample of young people in foster care (National Youth in Transition Database, NYTD) to examine the link between early childbirth and young women's access to postsecondary education between ages 19 and 21, controlling for an array of covariates. The study sample included 2,207 young women who had completed a high school diploma or GED by age 19 and who participated in three NYTD interviews at ages 17, 19 and 21. Childbirth between ages 19 and 21 was linked to decreased access to postsecondary education. However, no relationship was found between access to postsecondary education and childbirth by age 17 or childbirth between ages 17 and 19. Implications for policy, practice and research are discussed.  相似文献   
886.
Although there has been considerable research about attitudes towards LGBTQ+ people, there has been little research into how people first come to be aware of minoritized sexual and gender minority (SGM) identities. This study sought to address this gap. A sample of sexual minority (= 150) and heterosexual (= 802) young adults (= 952; Mage = 18.88 years, SD = 1.75; 949 were cisgender, three were transgender), primarily recruited from a large southern university, were asked retrospectively to recount their first exposure to or awareness of SGM identities. Responses between SGM and heterosexual participants were compared through a variety of analytical approaches, including analyzing themes about the source from which participants first recalled encountering these identities, and whether understanding about these identities came through a personal connection to someone with these identities. SGM participants reported encountering minoritized sexual identities a year earlier than did heterosexual participants, with both groups encountering these concepts in middle childhood, on average. SGM participants were more likely than heterosexual participants to report learning about minoritized gender identities from someone with a minoritized gender identity, while heterosexual participants more often reported learning about these identities from media or celebrities. Heterosexual (vs. SGM) participants were also more likely to imply that minoritized gender identities were adopted to be popular, rather than being authentic identities in themselves. Framed by developmental intergroup theory (DIT), we discuss implications of these findings, especially potential interrelationships with the development of prejudiced attitudes about SGM identities.  相似文献   
887.
Whereas the desire for revenge for an unjust deed is considered natural, its use within the therapeutic setting is scarce, specifically in sexually victimized children. The study aimed to find how experiencing sexual molestation during childhood and the revenge fantasy is reflected in drawings and narratives of sexually victimized children. Following ethical approval and signing a consent form, 14 children who experienced sexual abuse and were psychologically treated (ages 11–18) were recruited. They were asked to draw two drawings: “draw an unjust event that had happened to you” and “draw what you would have liked to happen to the person that unjustly treated you.” At completion, participants were asked to give a narrative to each drawing. Phenomenological analysis of the drawings and narratives indicated that most participants refrained from using more than two colours, did not draw the perpetrator and drew schematic figures. The main themes that emerged in the drawings and the narratives were feeling of loneliness, aloneness, and the desire for role reversal.  相似文献   
888.
Studies have highlighted the political, economic, and psychological factors in the debate over anthropogenic climate change—a hegemony approach—but have rarely focused on the stories and possibilities of people's transitions from climate change non-believer to climate change believer. Based on publicly accessible narratives, this study examines the stories of those who have switched from non-believer to believer—a narrative approach—and the dilemmas involved in those switches. Our investigation illuminates that a transition to climate change believer is a cultural and moral matter based on changing social relations of knowledge and what people regard as ignorable. We find that narratives of transition commonly describe interrelated shifts in three social relational factors: the narrator's notions of self, material reality, and justice. We term this contextualized transformative experience a relational rupture. Our narrative approach thus contextualizes climate change denialism within a person's web of social relations, not the hegemony of climate change communication alone. Moreover, we suggest that, since public debate and polarization on scientific topics such as climate change, vaccination, and COVID-19 are socially situated, they may potentially be socially bridged.  相似文献   
889.
ABSTRACT: This paper examines modes of child care choice for young children in urban Brazil. Analysis of child care in developing countries is rare, in spite of its relevance to many policy issues. We model child care choice as a function of characteristics of the child and the mother, including the mother's predicted wage and probability of employment, the presence of other young children and potential caregivers. The results highlight the importance of the institutional structure of the labour market and the formal child care market and reveal policy-relevant information regarding the allocation of child care responsibility among household members.  相似文献   
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