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61.
Most plants attract multiple flower visitors that may vary widely in their effectiveness as pollinators. Floral evolution is expected to reflect interactions with the most important pollinators, but few studies have quantified the contribution of different pollinators to current selection on floral traits. To compare selection mediated by diurnal and nocturnal pollinators on floral display and spur length in the rewarding orchid Gymnadenia conopsea, we manipulated the environment by conducting supplemental hand-pollinations and selective pollinator exclusions in two populations in central Norway. In both populations, the exclusion of diurnal pollinators significantly reduced seed production compared to open pollination, whereas the exclusion of nocturnal pollinators did not. There was significant selection on traits expected to influence pollinator attraction and pollination efficiency in both the diurnal and nocturnal pollination treatment. The relative strength of selection among plants exposed to diurnal and nocturnal visitors varied among traits and populations, but the direction of selection was consistent. The results suggest that diurnal pollinators are more important than nocturnal pollinators for seed production in the study populations, but that both categories contribute to selection on floral morphology. The study illustrates how experimental manipulations can link specific categories of pollinators to observed selection on floral traits, and thus improve our understanding of how species interactions shape patterns of selection.  相似文献   
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This paper is part of a two-year study to investigate the feasibility of initiating a Clean Development Mechanism (CDM) project in an indigenous community of Eastern Panamá, Ipetí-Emberá. We use participatory mapping and matrices as well as household surveys to develop a land-use/land-cover baseline scenario and examine the role of local participation in assessing land-use change. In Ipetí, land-use change has not occurred in a linear way over the last decades, and our data unveils socio-economic factors as potential key drivers of change. The concordance that we observed between geographic information and individual and collective perceptions of land-use change substantiates the possibility of using local knowledge in the establishment of baseline data for CDM projects. Our calculations suggest that the total carbon (C) stocks in the Tierra Colectiva (TC) of Ipetí-Emberá in 2004 represents a 47% reduction from the estimated C stock at the onset of settlement in the early 1970’s. Results from the participatory assessments predict that, in 2024 and in absence of a CDM project, the C stocks will decline from 301,859 t C in 2004 to 155,730 t C, which constitutes a reduction of 52%. The scenario with CDM estimates C stocks of 305,853 t C for 2024, a value slightly superior to the 2004 value. In the TC there is ground to believe that cattle ranching is likely to become an ever more important activity as the population is young and growing and cannot easily move elsewhere. Forests tend to be cleared for cultivation while pastures are established on short fallows. Our baseline scenario underlines the potential for a CDM project to make a significant difference in the future C stocks of this landscape.  相似文献   
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Sea turtle populations worldwide suffer from reduced survival of immatures and adults due to fishery bycatch. Unfortunately, information about the whereabouts of turtles outside the breeding habitat is scarce in most areas, hampering the development of spatially explicit conservation plans. In the Mediterranean, recoveries of adult females flipper-tagged on nesting beaches suggest that the Adriatic Sea and Gulf of Gabès are important foraging areas for adults, but such information could be heavily biased (observing and reporting bias). In order to obtain unbiased data, we satellite-tracked seven loggerhead sea turtles after they completed nesting in the largest known Mediterranean rookery (Bay of Laganas, Zakynthos, Greece). Three females settled in the north Adriatic Sea, one in the south Adriatic Sea and two in the Gulf of Gabès area at the completion of their post-nesting migrations (one individual did not occupy a distinct foraging area). The concordance of tracking results with information from recoveries of flipper-tagged turtles suggests that the north Adriatic Sea and the Gulf of Gabès represent key areas for female adult Mediterranean loggerhead sea turtles.  相似文献   
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The tsunami that struck South-east Asia on 26 December 2004 left more than 500,000 people in Aceh, Indonesia, homeless and displaced to temporary barracks and other communities. This study examines the associations between prolonged habitation in barracks and the nature of fears reported by school-age children and adolescents. In mid-2007, 30 months after the tsunami, the authors interviewed 155 child and parent dyads. Logistic regression analysis was used to compare the fears reported by children and adolescents living in barracks with those reported by their peers who were living in villages. After adjusting for demographic factors and tsunami exposure, the data reveals that children and adolescents living in barracks were three times more likely than those living in villages to report tsunami-related fears. The study demonstrates that continued residence in barracks 30 months after the tsunami is associated with higher rates of reporting tsunami-related fears, suggesting that barracks habitation has had a significant impact on the psychological experience of children and adolescents since the tsunami.  相似文献   
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The purpose of this study is to examine the associations between maternal mental health distress symptoms, including depression and post‐traumatic stress disorder, the extent to which the presence of a child's disaster‐related physical health problem(s) have interfered with daily functioning, and family cohesion over time among Sri Lankan mothers who survived the tsunami on 26 December 2004. Study variables were measured using a self‐report questionnaire administered approximately four months after the event and three years later in summer 2008. Univariate, bivariate, and multivariate analyses were conducted. Path analysis was employed to assess the relationships between the key variables over time and the correlations in the study variables at each time point. Among other findings, the results of the path analysis indicated that post‐traumatic stress symptom distress four months after the disaster significantly predicted variance in family cohesion three years later. Clinical and empirical research implications are presented and discussed.  相似文献   
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The American College of Obstetricians and Gynecologists currently recommends that all pregnant women be offered screening for chromosomal abnormalities, regardless of maternal age. Traditional screening tests have detection rates ranging from 85% to 90% and false-positive rates of 3% to 5%. A woman with an abnormal noninvasive test is offered a diagnostic test, but diagnostic tests are associated with a risk of pregnancy loss. Recently, analysis of cell-free fetal DNA (cffDNA) in maternal blood has been shown to have potential for the accurate detection of some of the common fetal autosomal aneuploidies. As part of a technology assessment for the California Technology Assessment Forum, we critically reviewed the evidence for the use of cffDNA as a prenatal screening test. We evaluated the evidence for its use as either a ‘primary’ or an ‘advanced’ screening test and for its use in screening for three different trisomies: 21, 18, and 13. We evaluated whether the use of cffDNA met established technology assessment criteria and established conclusions about evidence-based use of this new technology. © 2013 John Wiley & Sons, Ltd.  相似文献   
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In evolutionary biology, whether parents should enhance or reduce parental care according to mate ornamentation is a subject of great debate. However, the evolution of female ornaments can shed light on this question. In theory, female ornamentation should be traded off against fecundity and thus cannot be wholly informative to males without a direct indication of fecundity. Hence, direct cues of offspring quality should affect the relationship between male investment and female ornamentation. Under this hypothesis, we manipulated two direct cues of offspring quality (egg size and color) after first egg laying in the blue-footed booby and registered male incubation patterns. In this species, foot color is a dynamic signal of current condition and in females is traded off with egg size. We found that males spent more time incubating when paired with dull females but only in nests with large eggs. Males also spent less time incubating small dull eggs. Results indicate that egg size, a direct cue of reproductive value, affected the relationship between male effort and female ornamentation. Males may be willing to help females that have invested in offspring at the expense of ornamentation, which suggests compensation when females are in low condition. Another possibility is that males relax their effort when paired with highly ornamented and fecund females because they have high parenting abilities. Our findings suggest that the information conveyed by female ornaments may depend on direct cues of fecundity. Results also highlight that parental decisions are complex, modulated by a combination of information sources.  相似文献   
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