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Reducing emissions from deforestation and forest degradation (REDD+) is expected to generate co-benefits and safeguard the interests of people who live in the forested regions where emissions are reduced. Participatory measurement, reporting and verification (PMRV) is one way to ensure that the interests of local people are represented in REDD+. In order to design and use PMRV systems to monitor co-benefits and safeguards, we need to obtain input on how local people perceive REDD+. In the literature, this is widely discussed as “community perceptions of REDD+.” We systematically reviewed this literature to understand how these perceptions have been assessed, focusing specifically on how individual perceptions have been sampled and aggregated into “community perceptions.” Using Google Scholar, we identified 19 publications that reported community perceptions of REDD+, including perceptions of its design, implementation, impacts, relationship with land tenure, and both interest and actual participation by local people. These perceptions were elicited through surveys of probability samples of the local population and interviews with purposively selected community representatives. Many authors did not provide sufficient information on their methods to interpret the reported community perceptions. For example, there was often insufficient detail on the selection of respondents or sampling methods. Authors also reported perceptions by unquantified magnitudes (e.g., “most people”, “the majority”) that were difficult to assess or compare across cases. Given this situation in the scholarly literature, we expect that there are even more severe problems in the voluminous gray literature on REDD+ not indexed by Google Scholar. We suggest that readers need to be cognizant of these issues and that publication outlets should establish guidelines for better reporting, requiring information on the reference population, sampling methods, and methods used to aggregate individual responses into “community perceptions.” 相似文献
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Alexa R. Weingarden Peter I. Dosa Erin DeWinter Clifford J. Steer Megan K. Shaughnessy James R. Johnson Alexander Khoruts Michael J. Sadowsky 《PloS one》2016,11(1)
Fecal microbiota transplantation (FMT) is a highly effective therapy for recurrent Clostridium difficile infection (R-CDI), but its mechanisms remain poorly understood. Emerging evidence suggests that gut bile acids have significant influence on the physiology of C. difficile, and therefore on patient susceptibility to recurrent infection. We analyzed spore germination of 10 clinical C. difficile isolates exposed to combinations of bile acids present in patient feces before and after FMT. Bile acids at concentrations found in patients’ feces prior to FMT induced germination of C. difficile, although with variable potency across different strains. However, bile acids at concentrations found in patients after FMT did not induce germination and inhibited vegetative growth of all C. difficile strains. Sequencing of the newly identified germinant receptor in C. difficile, CspC, revealed a possible correspondence of variation in germination responses across isolates with mutations in this receptor. This may be related to interstrain variability in spore germination and vegetative growth in response to bile acids seen in this and other studies. These results support the idea that intra-colonic bile acids play a key mechanistic role in the success of FMT, and suggests that novel therapeutic alternatives for treatment of R-CDI may be developed by targeted manipulation of bile acid composition in the colon. 相似文献
95.
Using simulations to evaluate Mantel‐based methods for assessing landscape resistance to gene flow
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Katherine A. Zeller Tyler G. Creech Katie L. Millette Rachel S. Crowhurst Robert A. Long Helene H. Wagner Niko Balkenhol Erin L. Landguth 《Ecology and evolution》2016,6(12):4115-4128
Mantel‐based tests have been the primary analytical methods for understanding how landscape features influence observed spatial genetic structure. Simulation studies examining Mantel‐based approaches have highlighted major challenges associated with the use of such tests and fueled debate on when the Mantel test is appropriate for landscape genetics studies. We aim to provide some clarity in this debate using spatially explicit, individual‐based, genetic simulations to examine the effects of the following on the performance of Mantel‐based methods: (1) landscape configuration, (2) spatial genetic nonequilibrium, (3) nonlinear relationships between genetic and cost distances, and (4) correlation among cost distances derived from competing resistance models. Under most conditions, Mantel‐based methods performed poorly. Causal modeling identified the true model only 22% of the time. Using relative support and simple Mantel r values boosted performance to approximately 50%. Across all methods, performance increased when landscapes were more fragmented, spatial genetic equilibrium was reached, and the relationship between cost distance and genetic distance was linearized. Performance depended on cost distance correlations among resistance models rather than cell‐wise resistance correlations. Given these results, we suggest that the use of Mantel tests with linearized relationships is appropriate for discriminating among resistance models that have cost distance correlations <0.85 with each other for causal modeling, or <0.95 for relative support or simple Mantel r. Because most alternative parameterizations of resistance for the same landscape variable will result in highly correlated cost distances, the use of Mantel test‐based methods to fine‐tune resistance values will often not be effective. 相似文献
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Age‐related variation in the mechanical properties of foods processed by Sapajus libidinosus
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98.
Trophic niche ontogeny and palaeoecology of early Toarcian Stenopterygius (Reptilia: Ichthyosauria)
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Reconstructing ecological niche shifts during ontogeny in extinct animals with no living analogues is difficult without exceptional fossil collections. Here we demonstrate how a previously identified ontogenetic shift in the size and shape of the dentition in the early Toarcian ichthyosaur Stenopterygius quadriscissus accurately predicts a particular dietary shift. The smallest S. quadriscissus fed on small, burst‐swimming fishes, with a steady shift towards faster moving fish and cephalopods with increasing body size. Larger adult specimens appear to have been completely reliant on cephalopods, with fish completely absent from gut contents shortly after onset of sexual maturity. This is consistent with a previously proposed ontogenetic niche shift based on tooth shape and body size, corroborating the idea that dental ontogeny may be a useful predictor of dietary shifts in marine reptiles. Applying the theoretical framework used here to other extinct species will improve the resolution of palaeoecological reconstructions, where appropriate sample sizes exist. 相似文献
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Research finds that non-indigenous peoples often hold negative racial attitudes towards indigenous peoples. Contact theory suggests that interpersonal contact can positively influence majority group members’ attitudes regarding minority group members, raising the question of whether indigenous population growth in cities will alter non-indigenous peoples’ attitudes. Using original 2014 survey data, this paper examines the relationship between interpersonal contact and racial attitudes in Canadian prairie cities. The analysis finds that while personal ties to aboriginal peoples are correlated with lower new and old-fashioned racism scores, general contact with aboriginal peoples only correlates with old-fashioned racism scores. As such, growing urban indigenous populations – and thus increased aboriginal-non-aboriginal general contact – alone should not be expected to result in positive racial attitudes. This research advances understanding of contact theory by considering how education interacts with interpersonal contact, and informs on-going dialogue about current racial relations between non-indigenous and indigenous peoples in Canadian prairie cities. 相似文献
100.
Caroline?SchuppliEmail author Sofia?I.?F.?Forss Ellen?J.?M.?Meulman Nicole?Zweifel Kevin?C.?Lee Evasari?Rukmana Erin?R.?Vogel Maria?A.?van Noordwijk Carel?P.?van Schaik 《Frontiers in zoology》2016,13(1):43