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991.
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
992.
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
993.
Jacqueline A. Miller Edward A. Smith Donna Coffman Catherine Mathews Lisa Wegner 《Journal of research on adolescence》2016,26(4):673-686
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
994.
995.
David A. Wilkerson 《Journal of Technology in Human Services》2016,34(3):256-266
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
996.
Evaluating the Nature of the Still‐Face Effect in the Double Face‐to‐Face Still‐Face Paradigm Using Different Comparison Groups 下载免费PDF全文
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
997.
Prenatal Reflective Functioning and Accumulated Risk as Predictors of Maternal Interactive Behavior During Free Play,the Still‐Face Paradigm,and Two Teaching Tasks 下载免费PDF全文
Hanneke J. A. Smaling Stephan C. J. Huijbregts Jill Suurland Kristiaan B. van der Heijden Judi Mesman Stephanie H. M. van Goozen Hanna Swaab 《Infancy》2016,21(6):766-784
This study examined whether prenatal reflective functioning (RF) was related to mothers’ interactive style across contexts with their 6‐month‐old infants (M age = 6.02 months, SD = 0.41, 54% boys), and to what extent quality of prenatal RF could account for the influence of accumulated risk on maternal interactive behavior. Accumulated risk was defined as the sum‐score of a selection of risk factors that have been associated with suboptimal infant development. Mother–infant dyads (N = 133) were observed during free play, two teaching tasks, and the Still‐Face Paradigm (SFP). Better prenatal RF was associated with more positive maternal behavior in all settings and less negative behavior during teaching and SFP reengagement. Accumulated risk and prenatal RF predicted shared variance in maternal interactive behavior (with unique predictive effects observed only for RF on sensitivity during teaching and SFP play, and for accumulated risk on sensitivity and positive engagement during SFP play, and internalizing‐helplessness during SFP reengagement). Accumulated risk had an indirect effect on maternal sensitivity during teaching and SFP play through prenatal RF. These findings suggest not only that RF may be targeted prenatally to improve mother–infant interactions, but also that enhancing RF skills may ameliorate some of the negative consequences from more stable perinatal risk factors that influence parent–child interactions. 相似文献
998.
999.
Jochen Klenk Lars Schwickert Luca Palmerini Sabato Mellone Alan Bourke Espen A. F. Ihlen Ngaire Kerse Klaus Hauer Mirjam Pijnappels Matthis Synofzik Karin Srulijes Walter Maetzler Jorunn L. Helbostad Wiebren Zijlstra Kamiar Aminian Christopher Todd Lorenzo Chiari Clemens Becker for the FARSEEING Consortium 《European review of aging and physical activity》2016,13(1):8
Background
Real-world fall events objectively measured by body-worn sensors can improve the understanding of fall events in older people. However, these events are rare and hence challenging to capture. Therefore, the FARSEEING (FAll Repository for the design of Smart and sElf-adaptive Environments prolonging Independent livinG) consortium and associated partners started to build up a meta-database of real-world falls.Results
Between January 2012 and December 2015 more than 300 real-world fall events have been recorded. This is currently the largest collection of real-world fall data recorded with inertial sensors. A signal processing and fall verification procedure has been developed and applied to the data. Since the end of 2015, 208 verified real-world fall events are available for analyses. The fall events have been recorded within several studies, with different methods, and in different populations. All sensor signals include at least accelerometer measurements and 58 % additionally include gyroscope and magnetometer measurements. The collection of data is ongoing and open to further partners contributing with fall signals. The FARSEEING consortium also aims to share the collected real-world falls data with other researchers on request.Conclusions
The FARSEEING meta-database will help to improve the understanding of falls and enable new approaches in fall risk assessment, fall prevention, and fall detection in both aging and disease.1000.
Melissa A. Lewis Dana M. Litt Jessica M. Cronce Jessica A. Blayney Amanda K. Gilmore 《Journal of sex research》2014,51(1):86-96
Individuals who engage in risky sexual behavior face the possibility of experiencing negative consequences. One tenet of social learning theory is that individuals engage in behaviors partly based on observations or perceptions of others’ engagement in those behaviors. The present study aimed to document these norms–behavior relationships for both risky and protective sexual behaviors, including alcohol-related sexual behavior. Gender was also examined as a possible moderator of the norms–behavior relationship. Undergraduate students (n = 759; 58.0% female) completed a Web-based survey, including various measures of drinking and sexual behavior. Results indicated that students underestimate sexual health-protective behaviors (e.g., condom use and birth control use) and overestimate the risky behaviors (e.g., frequency of drinking prior to sex, typical number of drinks prior to sex, and frequency of casual sex) of their same-sex peers. All norms were positively associated with behavior, with the exception of condom use. Furthermore, no gender differences were found when examining the relationship between normative perceptions and behavior. The present study adds to the existing literature on normative misperceptions as it indicates that college students overestimate risky sexual behavior while underestimating sexual health-protective behaviors. Implications for interventions using the social norm approach and future directions are discussed. 相似文献