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311.
Journal of Material Cycles and Waste Management - Biomass and waste polystyrene plastic (ratio 1:1) were co-pyrolysed followed by catalysis in a two-stage fixed bed reactor system to produce...  相似文献   
312.
Cuticular hydrocarbons have been identified as the source of sex-recognition signals for many insects, but for social insects, specifically ants, cuticular hydrocarbon profiles of males are often ignored. This study reports male-specific cuticular hydrocarbon patterns for the trap-jaw ant Odontomachus brunneus. Analysis of samples from four Florida populations demonstrated that male-specific overabundance of four hydrocarbons is conserved across populations despite population-level divergence of the remainder of the profile. In addition, hydrocarbon patterns unique to adult males were not present on the cuticle of final instar male larvae, indicating that male-specific profiles arise late in development. The pattern of an abundant subset of conserved cuticular hydrocarbons characteristic of males across divergent populations was compared to earlier findings of the conservation of fertility signals of females across these same populations.  相似文献   
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Organic acids present in the rhizosphere of growing plants are widely recognized to be responsible for dissolving the solid phase metals in the soil and making them available for plant absorption. We proposed a root exudates-based model to assess the long-term phytoavailability of metals in biosolids-amended soils. The phytoavailability of biosolids-borne metals was defined in terms of a capacity factor and an intensity factor. The plant available metal pool, C0 (capacity factor, mg kg−1), can be estimated by fitting the successive organic acids extraction data to an exponential decay kinetic equation. The field metal removal rate, k (intensity factor, yr−1), can be estimated from the successive extraction-based metal release rate through an effective annual organic acid production in the rhizosphere which was found to be characteristic of plant species. The protocol was successfully used to assess the long-term phytoavailability of metals in biosolids-amended soil from two biosolids land application sites.  相似文献   
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Global biodiversity losses continue despite tremendous growth in the volume of conservation science and many local successes. Research that can achieve conservation science's aims—arresting declines in biodiversity and preventing extinctions—is therefore of ever greater importance. Here, we ask whether conservation science, as currently performed, is progressing in such a way as to maximize its impact. We present a simple framework for how effective conservation research could progress, from identifying problems to diagnosing their proximate and ultimate causes, and from proposing, to designing, implementing, and testing responses. We then demonstrate that for three well-known examples—South Asian vultures, whooping cranes, and bycatch of procellariform seabirds—published studies appear to follow this sequence, with considerable benefits. However, for a representative sample of the wider conservation literature, we find no evidence of such a progression. Instead, the vast majority of papers remain focused on describing the state of nature or on mechanisms directly causing changes, with very little research on designing or implementing conservation responses. This lack of research on the sorts of questions that might most help conservation science deliver its stated mission strongly suggests we will struggle to translate the huge increase in research activity into real-world benefits.  相似文献   
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As coral reefs continue to decline due to climate change and other stressors, scientists have proposed adopting genomic tools, such as biomarkers, to aid in the conservation and restoration of these threatened ecosystems. Biomarkers are easily measured indicators of biological processes that can be used to predict or diagnose health, resilience, and other key performance metrics. The ultimate goal of developing biomarkers is to determine the conservation value and utility of a given coral colony, including the host animal, its algal symbionts, and their microbial partners. However, this goal remains distant because most efforts have not yet moved beyond the initial discovery phase. We review recent progress in the development of coral molecular biomarkers from a practical standpoint and consider the many challenges that remain as roadblocks to large-scale implementation. We caution practitioners that, while biomarkers are a promising technology, they are unlikely to be available for field application in the near future barring a rapid shift in research focus from discovery to subsequent validation and field trials. To facilitate such a shift, we propose a stepwise framework to guide additional study in this area, with the aim of accelerating practical molecular biomarker development to enhance coral restoration practice.  相似文献   
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The purpose of this paper is to assess the consistency of the historic record of mean global temperature with a climate model of historic greenhouse warming. Because there is no natural parametric alternative to the climate model, goodness-of-fit is assessed via nonparametric regression. While the historic record is not consistent with the model with high temperature sensitivity, it is not inconsistent with the model using the best-fitting temperature sensitivity.  相似文献   
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