9 research outputs found

    Nanoinformatics: developing new computing applications for nanomedicine

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    Nanoinformatics has recently emerged to address the need of computing applications at the nano level. In this regard, the authors have participated in various initiatives to identify its concepts, foundations and challenges. While nanomaterials open up the possibility for developing new devices in many industrial and scientific areas, they also offer breakthrough perspectives for the prevention, diagnosis and treatment of diseases. In this paper, we analyze the different aspects of nanoinformatics and suggest five research topics to help catalyze new research and development in the area, particularly focused on nanomedicine. We also encompass the use of informatics to further the biological and clinical applications of basic research in nanoscience and nanotechnology, and the related concept of an extended ?nanotype? to coalesce information related to nanoparticles. We suggest how nanoinformatics could accelerate developments in nanomedicine, similarly to what happened with the Human Genome and other -omics projects, on issues like exchanging modeling and simulation methods and tools, linking toxicity information to clinical and personal databases or developing new approaches for scientific ontologies, among many others

    Towards crystal structure prediction of complex organic compounds - a report on the fifth blind test

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    Following on from the success of the previous crystal structure prediction blind tests (CSP1999, CSP2001, CSP2004 and CSP2007), a fifth such collaborative project (CSP2010) was organized at the Cambridge Crystallographic Data Centre. A range of methodologies was used by the participating groups in order to evaluate the ability of the current computational methods to predict the crystal structures of the six organic molecules chosen as targets for this blind test. The first four targets, two rigid molecules, one semi-flexible molecule and a 1: 1 salt, matched the criteria for the targets from CSP2007, while the last two targets belonged to two new challenging categories - a larger, much more flexible molecule and a hydrate with more than one polymorph. Each group submitted three predictions for each target it attempted. There was at least one successful prediction for each target, and two groups were able to successfully predict the structure of the large flexible molecule as their first place submission. The results show that while not as many groups successfully predicted the structures of the three smallest molecules as in CSP2007, there is now evidence that methodologies such as dispersion-corrected density functional theory (DFT-D) are able to reliably do so. The results also highlight the many challenges posed by more complex systems and show that there are still issues to be overcome

    Resource pre-emption, rather than extending the growing season of native grass assemblages, reduces invasion by exotic species

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    Questions: In Mediterranean-type systems, invasive C3 annual grasses appear early in the season and can pre-empt resources and attain a competitive dominance over native perennial grasses. Here, we investigated whether planting C3 and C4 native grasses (a) combined, so that resources are extracted over a longer period, or (b) at higher density would make planted communities more competitive against invasive species. Location: Para Woodlands Reserve, near Adelaide, South Australia. Methods: In 72 experimental plots, native grasses were planted in combinations of seasonal patterns (three levels; single-season assemblages with either C3 or C4 and extended season with both C3 and C4) and planting density (two levels; high = 44 plants/m2 and low = 20 plants/m2 ). Data were collected on native plant survival and biomass, invasive biomass and soil properties. Results: Overall, C3 native grasses were superior competitors against both invasive C3 grasses and native C4 grasses. We found no interaction between the combination of C3 and C4 grasses planted together and density of planting. Assemblages with higher densities were successful at reducing exotic plant biomass; however, there was a trade-off with reduced individual performance among the native plants. Even though individual plants were larger in the low-density treatment, total biomass was lower in these plots suggesting that density limits the growth of native communities as a whole. The C3 native plants were planted earlier than the C4 native plants because of differences in phenology and therefore likely pre-empted resources and gained a size advantage, making them the superior competitor. Conclusion: Native perennial grasses can outcompete exotic plants for resources if planted earlier in the season. This resource pre-emption appears to be more important than resource use over a longer period with C3 and C4 plants together and could be an effective restoration strategy

    Site preparation impacts on soil biotic and abiotic properties, weed control, and native grass establishment

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    In severely degraded systems active restoration is required to overcome legacies of past land use and to create conditions that promote the establishment of target plant communities. While our understanding of the importance of soil microbial communities in ecological restoration is growing, few studies have looked at the impacts different site preparation techniques have on these communities. We trialed four methods of site preparation: fire, top-soil removal (TSR; removal of top 50 mm of soil), slashing (vegetation cut to 30 mm, biomass removed), and carbon (C; as sugar and saw-dust) addition, and quantified resulting soil bacterial communities using DNA metabarcoding. We compared the effectiveness of these techniques to reduce weed biomass, improve native grass establishment, and induce changes in soil nutrient availability. TSR was the most effective technique, leading to a reduction in both available nutrients and competition from weeds. In comparison, the remaining methods had little or no effect on weed biomass, native grass establishment, or soil nutrient availability. Both TSR and C addition resulted in changes in the soil bacterial community. These changes have the potential to alter plant community assembly in many ways, such as via nutrient acquisition, pathogenic effects, nutrient cycling, and decomposition. We recommend TSR for ecological restoration of old-fields and suggest it is a much more effective technique than burning, slashing, or C addition. Restoration practitioners should consider how their management techniques may influence the soil biota and, in turn, affect restoration outcomes

    Correlations between physical and chemical defences in plants: tradeoffs, syndromes, or just many different ways to skin a herbivorous cat?

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    � Most plant species have a range of traits that deter herbivores. However, understanding of how different defences are related to one another is surprisingly weak. Many authors argue that defence traits trade off against one another, while others argue that they form coordinated defence syndromes. � We collected a dataset of unprecedented taxonomic and geographic scope (261 species spanning 80 families, from 75 sites across the globe) to investigate relationships among four chemical and six physical defences. � Five of the 45 pairwise correlations between defence traits were significant and three of these were tradeoffs. The relationship between species’ overall chemical and physical defence levels was marginally nonsignificant (P = 0.08), and remained nonsignificant after accounting for phylogeny, growth form and abundance. Neither categorical principal component analysis (PCA) nor hierarchical cluster analysis supported the idea that species displayed defence syndromes. � Our results do not support arguments for tradeoffs or for coordinated defence syndromes. Rather, plants display a range of combinations of defence traits. We suggest this lack of consistent defence syndromes may be adaptive, resulting from selective pressure to deploy a different combination of defences to coexisting species

    Significant progress in predicting the crystal structures of small organic molecules – a report on the fourth blind test

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    We report on the organization and outcome of the fourth blind test of crystal structure prediction, an international collaborative project organized to evaluate the present state in computational methods of predicting the crystal structures of small organic molecules. There were 14 research groups which took part, using a variety of methods to generate and rank the most likely crystal structures for four target systems: three single-component crystal structures and a 1:1 cocrystal. Participants were challenged to predict the crystal structures of the four systems, given only their molecular diagrams, while the recently determined but as-yet unpublished crystal structures were withheld by an independent referee. Three predictions were allowed for each system. The results demonstrate a dramatic improvement in rates of success over previous blind tests; in total, there were 13 successful predictions and, for each of the four targets, at least two groups correctly predicted the observed crystal structure. The successes include one participating group who correctly predicted all four crystal structures as their first ranked choice, albeit at a considerable computational expense. The results reflect important improvements in modelling methods and suggest that, at least for the small and fairly rigid types of molecules included in this blind test, such calculations can be constructively applied to help understand crystallization and polymorphism of organic molecules.<br/

    Putting plant resistance traits on the map : a test of the idea that plants are better defended at lower latitudes

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    It has long been believed that plant species from the tropics have higher levels of traits associated with resistance to herbivores than do species from higher latitudes. A meta-analysis recently showed that the published literature does not support this theory. However, the idea has never been tested using data gathered with consistent methods from a wide range of latitudes. We quantified the relationship between latitude and a broad range of chemical and physical traits across 301 species from 75 sites world-wide. Six putative resistance traits, including tannins, the concentration of lipids (an indicator of oils, waxes and resins), and leaf toughness were greater in high-latitude species. Six traits, including cyanide production and the presence of spines, were unrelated to latitude. Only ash content (an indicator of inorganic substances such as calcium oxalates and phytoliths) and the properties of species with delayed greening were higher in the tropics. Our results do not support the hypothesis that tropical plants have higher levels of resistance traits than do plants from higher latitudes. If anything, plants have higher resistance toward the poles. The greater resistance traits of high-latitude species might be explained by the greater cost of losing a given amount of leaf tissue in low-productivity environments.12 page(s
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