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891.
892.
What motivates the geographic footprint of the supply chains that multinational firms (MNFs) deploy? Traditional research in the operations and supply chain management literature tends to recommend locations primarily based on differentials in production costs and the ramifications of physical distance ignoring the role of taxation. MNFs that strategically position parts of their supply chains in low‐tax locations can allocate the profits across the divisions to improve post‐tax profits. For the profit allocation to be defensible to tax authorities, the divisional operations must possess real decision authority and bear meaningful risks. Generally speaking, the greater the transfer of risk and control, the larger the allowable allocation of profit. These transfers may also create inefficiencies due to misalignment of business goals and attitudes toward risk. We model these trade‐offs in the context of placing in a low‐tax region a subsidiary that oversees product distribution (as a limited risk distributor commissionnaire, limited risk distributor, or fully fledged distributor). Our analysis demonstrates that the MNF's preferences regarding the operating structures are not necessarily an obvious ordering based on the amount of risk and decision authority transferred to the division in the low‐tax jurisdiction. We derive and analyze threshold values of the performance parameters that describe the main trade‐offs involved in selecting an operating structure. We find some of the optimal decisions to exhibit interesting non‐monotone behavior. For instance, profits can increase when the tax rate in the low‐tax jurisdiction increases. Numerical analysis shows that the Limited‐Risk Distributor structure is rarely optimal and quantifies when each alternative dominates it.  相似文献   
893.
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   
894.
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   
895.
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   
896.
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   
897.
Nearly 20% of South African youth experience forced or coerced sexual intercourse. Understanding the factors associated with forced sex is important for informing prevention programs aimed at reducing sexual violence and HIV and AIDS. Multilevel regression models test the association between sexual situation self‐efficacy and forced sex among 2,893 South African adolescents. Findings suggest that youth are more likely to experience forced sex after periods of time when their levels of self‐efficacy are lower than their average levels of self‐efficacy. Furthermore, youth who are lower on their self‐efficacy compared to their peers are more likely to experience forced sex. Implications for prevention research are discussed.  相似文献   
898.
899.
Improving outcomes of telebehavioral psychoeducation requires rethinking program design when delivered wholly or partially for self-directed participation. Discussion forum participation often follows the “90-9-1 Rule” where 90% of participants lurk, rather than contribute content. A theoretical perspective on the behavior can help explain its adaptive functions, as well as the threats that this behavior poses to the lurker. Implications for practice require program redesign that actively links individual skills training and group-based discussion. The proposed linking design can synergize individual and group participation to support the development of mutual aid, as well as greater interaction with psychoeducation content and materials.  相似文献   
900.
The current study explored two possible comparison groups for the double Face‐to‐Face Still‐Face (FFSF) paradigm to evaluate their effects on infant behavior and different hypotheses about the nature of the Still‐Face (SF) effect, an effect not fully understood. Mothers and their 4‐month‐old infants were randomly assigned to one of three groups, a double FFSF group (GroupFFSF, n = 44), a control, semi‐structured play group (GroupStory, n = 46), or a control, unstructured play group (GroupPlay, n = 28). As hypothesized, GroupFFSF infants exhibited the classic SF response (decreased positive affect and gaze to mother; increased negative affect) and GroupPlay infants showed an increase in negative affect over episodes. Contrary to expectations, GroupStory infants displayed a similar, but less intense, pattern of behavior as GroupFFSF. Taken together, the findings indicate that multiple episodes of face‐to‐face play exceeded 4‐month‐olds' regulatory capacities and that infants are sensitive to shared communicative intentions and violations of social expectations, whether these violations are negative or positive in nature.  相似文献   
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