| 1081. |
- Stuart-Smith, Rick D., et al.
(author)
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Integrating abundance and functional traits reveals new global hotspots of fish diversity
- 2013
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 501:7468, s. 539-
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Journal article (peer-reviewed)abstract
- Species richness has dominated our view of global biodiversity patterns for centuries(1,2). The dominance of this paradigm is reflected in the focus by ecologists and conservation managers on richness and associated occurrence-based measures for understanding drivers of broad-scale diversity patterns and as a biological basis for management(3,4). However, this is changing rapidly, as it is now recognized that not only the number of species but the species present, their phenotypes and the number of individuals of each species are critical in determining the nature and strength of the relationships between species diversity and a range of ecological functions (such as biomass production and nutrient cycling)(5). Integrating these measures should provide a more relevant representation of global biodiversity patterns in terms of ecological functions than that provided by simple species counts. Here we provide comparisons of a traditional global biodiversity distribution measure based on richness with metrics that incorporate species abundances and functional traits. We use data from standardized quantitative surveys of 2,473 marine reef fish species at 1,844 sites, spanning 133 degrees of latitude from all ocean basins, to identify new diversity hotspots in some temperate regions and the tropical eastern Pacific Ocean. These relate to high diversity of functional traits amongst individuals in the community (calculated using Rao's Q(6)), and differ from previously reported patterns in functional diversity and richness for terrestrial animals, which emphasize species-rich tropical regions only(7,8). There is a global trend for greater evenness in the number of individuals of each species, across the reef fish species observed at sites ('community evenness'), at higher latitudes. This contributes to the distribution of functional diversity hotspots and contrasts with well-known latitudinal gradients in richness(2,4). Our findings suggest that the contribution of species diversity to a range of ecosystem functions varies over large scales, and imply that in tropical regions, which have higher numbers of species, each species contributes proportionally less to community-level ecological processes on average than species in temperate regions. Metrics of ecological function usefully complement metrics of species diversity in conservation management, including when identifying planning priorities and when tracking changes to biodiversity values.
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| 1082. |
- Stuart-Smith, Rick D., et al.
(author)
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Thermal biases and vulnerability to warming in the world's marine fauna
- 2015
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 528:7580, s. 88-
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Journal article (peer-reviewed)abstract
- A critical assumption underlying projections of biodiversity change associated with global warming is that ecological communities comprise balanced mixes of warm-affinity and cool-affinity species which, on average, approximate local environmental temperatures. Nevertheless, here we find that most shallow water marine species occupy broad thermal distributions that are aggregated in either temperate or tropical realms. These distributional trends result in ocean-scale spatial thermal biases, where communities are dominated by species with warmer or cooler affinity than local environmental temperatures. We use community-level thermal deviations from local temperatures as a form of sensitivity to warming, and combine these with projected ocean warming data to predict warming-related loss of species from present-day communities over the next century. Large changes in local species composition appear likely, and proximity to thermal limits, as inferred from present-day species' distributional ranges, outweighs spatial variation in warming rates in contributing to predicted rates of local species loss.
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| 1083. |
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| 1084. |
- Ståhl, Göran, et al.
(author)
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Plant functional traits have globally consistent effects on competition
- 2016
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 529, s. 204-U174
-
Journal article (peer-reviewed)abstract
- Phenotypic traits and their associated trade-offs have been shown to have globally consistent effects on individual plant physiological functions(1-3), but how these effects scale up to influence competition, a key driver of community assembly in terrestrial vegetation, has remained unclear (4). Here we use growth data from more than 3 million trees in over 140,000 plots across the world to show how three key functional traits-wood density, specific leaf area and maximum height-consistently influence competitive interactions. Fast maximum growth of a species was correlated negatively with its wood density in all biomes, and positively with its specific leaf area in most biomes. Low wood density was also correlated with a low ability to tolerate competition and a low competitive effect on neighbours, while high specific leaf area was correlated with a low competitive effect. Thus, traits generate trade-offs between performance with competition versus performance without competition, a fundamental ingredient in the classical hypothesis that the coexistence of plant species is enabled via differentiation in their successional strategies(5). Competition within species was stronger than between species, but an increase in trait dissimilarity between species had little influence in weakening competition. No benefit of dissimilarity was detected for specific leaf area or wood density, and only a weak benefit for maximum height. Our trait-based approach to modelling competition makes generalization possible across the forest ecosystems of the world and their highly diverse species composition.
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| 1085. |
- Ståhl, Patrik, Dr.
(author)
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Gene expression of single cells mapped in tissue sections
- 2024
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In: Nature. - : Springer Nature. - 0028-0836 .- 1476-4687. ; 625:7993, s. 38-39
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Journal article (other academic/artistic)abstract
- A tool that tags individual cells in a tissue with a unique barcode means that the gene-expression profile of each cell can be plotted in its original location. This allows spatial information to be captured at single-cell resolution.
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| 1086. |
- Su, Jun, et al.
(author)
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Expression of barley SUSIBA2 transcription factor yields high-starch low-methane rice
- 2015
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 523, s. 602-606
-
Journal article (peer-reviewed)abstract
- Atmospheric methane is the second most important greenhouse gas after carbon dioxide, and is responsible for about 20% of the global warming effect since pre-industrial times(1,2). Rice paddies are the largest anthropogenic methane source and produce 7-17% of atmospheric methane(2,3). Warm waterlogged soil and exuded nutrients from rice roots provide ideal conditions for methanogenesis in paddies with annual methane emissions of 25-100-million tonnes(3,4). This scenario will be exacerbated by an expansion in rice cultivation needed to meet the escalating demand for food in the coming decades(4). There is an urgent need to establish sustainable technologies for increasing rice production while reducing methane fluxes from rice paddies. However, ongoing efforts for methane mitigation in rice paddies are mainly based on farming practices and measures that are difficult to implement(5). Despite proposed strategies to increase rice productivity and reduce methane emissions(4,6), no high-starch low-methane-emission rice has been developed. Here we show that the addition of a single transcription factor gene, barley SUSIBA2 (refs 7, 8), conferred a shift of carbon flux to SUSIBA2 rice, favouring the allocation of photo-synthates to aboveground biomass over allocation to roots. The altered allocation resulted in an increased biomass and starch content in the seeds and stems, and suppressed methanogenesis, possibly through a reduction in root exudates. Three-year field trials in China demonstrated that the cultivation of SUSIBA2 rice was associated with a significant reduction in methane emissions and a decrease in rhizospheric methanogen levels. SUSIBA2 rice offers a sustainable means of providing increased starch content for food production while reducing greenhouse gas emissions from rice cultivation. Approaches to increase rice productivity and reduce methane emissions as seen in SUSIBA2 rice may be particularly beneficial in a future climate with rising temperatures resulting in increased methane emissions from paddies(9,10).
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| 1087. |
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| 1088. |
- Sukonina, Valentina, et al.
(author)
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FOXK1 and FOXK2 regulate aerobic glycolysis.
- 2019
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In: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 566, s. 279-283
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Journal article (peer-reviewed)abstract
- Adaptation to the environment and extraction of energy are essential for survival. Some species have found niches and specialized in using a particular source of energy, whereas others-including humans and several other mammals-have developed a high degree of flexibility1. A lot is known about the general metabolic fates of different substrates but we still lack a detailed mechanistic understanding of how cells adapt in their use of basic nutrients2. Here we show that the closely related fasting/starvation-induced forkhead transcription factors FOXK1 and FOXK2 induce aerobic glycolysis by upregulating the enzymatic machinery required for this (for example, hexokinase-2, phosphofructokinase, pyruvate kinase, and lactate dehydrogenase), while at the same time suppressing further oxidation of pyruvate in the mitochondria by increasing the activity of pyruvate dehydrogenase kinases 1 and 4. Together with suppression of the catalytic subunit of pyruvate dehydrogenase phosphatase 1 this leads to increased phosphorylation of the E1α regulatory subunit of the pyruvate dehydrogenase complex, which in turn inhibits further oxidation of pyruvate in the mitochondria-instead, pyruvate is reduced to lactate. Suppression of FOXK1 and FOXK2 induce the opposite phenotype. Both in vitro and in vivo experiments, including studies of primary human cells, show how FOXK1 and/or FOXK2 are likely to act as important regulators that reprogram cellular metabolism to induce aerobic glycolysis.
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| 1089. |
|
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| 1090. |
- Sun, Jian-Ke, et al.
(author)
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Enhancing crystal growth using polyelectrolyte solutions and shear flow
- 2020
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 579:7797, s. 73-79
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Journal article (peer-reviewed)abstract
- The ability to grow properly sized and good quality crystals is one of the cornerstones of single-crystal diffraction, is advantageous in many industrial-scale chemical processes(1-3), and is important for obtaining institutional approvals of new drugs for which high-quality crystallographic data are required(4-7). Typically, single crystals suitable for such processes and analyses are grown for hours to days during which any mechanical disturbances-believed to be detrimental to the process-are carefully avoided. In particular, stirring and shear flows are known to cause secondary nucleation, which decreases the final size of the crystals (though shear can also increase their quantity(8-14)). Here we demonstrate that in the presence of polymers (preferably, polyionic liquids), crystals of various types grow in common solvents, at constant temperature, much bigger and much faster when stirred, rather than kept still. This conclusion is based on the study of approximately 20 diverse organic molecules, inorganic salts, metal-organic complexes, and even some proteins. On typical timescales of a few to tens of minutes, these molecules grow into regularly faceted crystals that are always larger (with longest linear dimension about 16 times larger) than those obtained in control experiments of the same duration but without stirring or without polymers. We attribute this enhancement to two synergistic effects. First, under shear, the polymers and their aggregates disentangle, compete for solvent molecules and thus effectively 'salt out' (that is, induce precipitation by decreasing solubility of) the crystallizing species. Second, the local shear rate is dependent on particle size, ultimately promoting the growth of larger crystals (but not via surface-energy effects as in classical Ostwald ripening). This closed-system, constant-temperature crystallization driven by shear could be a valuable addition to the repertoire of crystal growth techniques, enabling accelerated growth of crystals required by the materials and pharmaceutical industries.
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