58 research outputs found
Leaf nutrients, not specific leaf area, are consistent indicators of elevated nutrient inputs
Leaf traits are frequently measured in ecology to provide a ‘common currency’ for predicting how anthropogenic pressures impact ecosystem function. Here, we test whether leaf traits consistently respond to experimental treatments across 27 globally distributed grassland sites across 4 continents. We find that specific leaf area (leaf area per unit mass)—a commonly measured morphological trait inferring shifts between plant growth strategies—did not respond to up to four years of soil nutrient additions. Leaf nitrogen, phosphorus and potassium concentrations increased in response to the addition of each respective soil nutrient. We found few significant changes in leaf traits when vertebrate herbivores were excluded in the short-term. Leaf nitrogen and potassium concentrations were positively correlated with species turnover, suggesting that interspecific trait variation was a significant predictor of leaf nitrogen and potassium, but not of leaf phosphorus concentration. Climatic conditions and pretreatment soil nutrient levels also accounted for significant amounts of variation in the leaf traits measured. Overall, we find that leaf morphological traits, such as specific leaf area, are not appropriate indicators of plant response to anthropogenic perturbations in grasslands
Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus
A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10-20), ER-negative BC (P=1.1 × 10-13), BRCA1-associated BC (P=7.7 × 10-16) and triple negative BC (P-diff=2 × 10-5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10-3) and ABHD8 (P<2 × 10-3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk
Genome-Wide Association Study in BRCA1 Mutation Carriers Identifies Novel Loci Associated with Breast and Ovarian Cancer Risk
BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10-8, HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10-8, HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4×10-8, HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific associat
BOTTOM-UP AND TOP-DOWN INTERACTIONS IN COASTAL INTERFACE SYSTEMS
The land–sea margin encompasses a variety of hard and soft-bottom habitats where organisms are exposed to a dynamic range of aquatic and atmospheric conditions dependent on a rhythm set by the tides. In this chapter, we focus on rocky intertidal and salt marsh ecosystems, which have been extensively studied on many continents. Both rocky shore and salt marsh communities exhibit strong and consistent patterns of intertidal zonation over relatively compressed spatial scales, making them excellent systems for understanding the context-dependency of species interactions. Hard-bottomed rocky intertidal communities are dominated by marine macroalgae and sessile marine invertebrates extending their reach to the furthest edge of the influence of sea spray, while soft-bottomed salt marsh communities are anchored by terrestrial plants with adaptations or tolerance to inundation by salty and brackish waters. Rocky shore communities may be battered by the full force of large ocean waves or gently lapped with seawater on more protected shorelines. In contrast, salt marshes are restricted to quiet waters where sediment accretion by plants is the main mechanism for habitat creation. Both communities may experience very large tidal excursions or only minimal ones, depending on the local dynamics of the tides, with corresponding consequences for the spatial extent of these communities across the shoreline. The steep environmental gradients and distinctive biological zonation patterns that characterize both rocky shore and salt marsh ecosystems (Fig. 7.1) have provided ecologists with accessible and highly tractable ecosystems for investigating the role of bottom-up and top-down factors along environmental gradients
The Usefulness of Sustainability Indicators for Policy Making in Developing Countries: The Case of Madagascar
Response to Comments on “Productivity Is a Poor Predictor of Plant Species Richness”
Pan et al. claim that our results actually support a strong linear positive relationship between productivity and richness, whereas Fridley et al. contend that the data support a strong humped relationship. These responses illustrate how preoccupation with bivariate patterns distracts from a deeper understanding of the multivariate mechanisms that control these important ecosystem properties
Author Correction: Leaf nutrients, not specific leaf area, are consistent indicators of elevated nutrient inputs (Nature Ecology & Evolution, (2019), 3, 3, (400-406), 10.1038/s41559-018-0790-1)
An amendment to this paper has been published and can be accessed via a link at the top of the paper
Author Correction: Leaf nutrients, not specific leaf area, are consistent indicators of elevated nutrient inputs (Nature Ecology & Evolution, (2019), 3, 3, (400-406), 10.1038/s41559-018-0790-1)
Electroweak measurements in electron–positron collisions at w-boson-pair energies at lep
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Modeling Above-Ground Biomass in Tallgrass Prairie Using Ultra-High Spatial Resolution sUAS Imagery
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