Escuela Politécnica del Ejército

About: Escuela Politécnica del Ejército is a education organization based out in Sangolquí, Ecuador. It is known for research contribution in the topics: Computer science & Population. The organization has 2891 authors who have published 2690 publications receiving 24292 citations. The organization is also known as: ESPE Army University.

An application of nanotechnology in advanced dental materials

Abstract: Background This article reports the authors' development of nanofillers and a resulting nanocomposite They measured the nanocomposite's properties in vitro in comparison with those of several existing composites (hybrids, microhybrids and microfill) Methods The authors developed two types of nanofillers: nanomeric particles and nanoclusters They used optimal combinations of these nanofillers in a proprietary resin matrix to prepare the nanocomposite system with a wide range of shades and opacities The properties they studied were compressive, diametral tensile and flexural strengths; in vitro three-body wear; fracture resistance; polish retention; and surface morphology after toothbrush abrasion They performed statistical analysis using analysis of variance/Tukey-Kramer paired analysis at a 95 percent confidence interval Results The compressive and diametral strengths and the fracture resistance of the nanocomposite were equivalent to or higher than those of the other commercial composites tested The three-body wear results of the nanocomposite system were statistically better than those of all other composites tested The nanocomposite showed better polish retention than the hybrids and microhybrids tested at the extended brushing periods After extended toothbrush abrasion, the dentin, body and enamel shades showed polish retention equivalent to that of the microfill tested, while translucent shades showed better polish retention than the microfill Conclusions The dental nanocomposite system studied showed high translucency, high polish and polish retention similar to those of microfills while maintaining physical properties and wear resistance equivalent to those of several hybrid composites Clinical Implications The strength and esthetic properties of the resin-based nanocomposite tested should allow the clinician to use it for both anterior and posterior restorations

TRY plant trait database : Enhanced coverage and open access

Abstract: Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.

Genome Analyses of an Aggressive and Invasive Lineage of the Irish Potato Famine Pathogen

Abstract: Pest and pathogen losses jeopardise global food security and ever since the 19 th century Irish famine, potato late blight has exemplified this threat. The causal oomycete pathogen, Phytophthora infestans, undergoes major population shifts in agricultural systems via the successive emergence and migration of asexual lineages. The phenotypic and genotypic bases of these selective sweeps are largely unknown but management strategies need to adapt to reflect the changing pathogen population. Here, we used molecular markers to document the emergence of a lineage, termed 13_A2, in the European P. infestans population, and its rapid displacement of other lineages to exceed 75% of the pathogen population across Great Britain in less than three years. We show that isolates of the 13_A2 lineage are among the most aggressive on cultivated potatoes, outcompete other aggressive lineages in the field, and overcome previously effective forms of plant host resistance. Genome analyses of a 13_A2 isolate revealed extensive genetic and expression polymorphisms particularly in effector genes. Copy number variations, gene gains and losses, amino-acid replacements and changes in expression patterns of disease effector genes within the 13_A2 isolate likely contribute to enhanced virulence and aggressiveness to drive this population displacement. Importantly, 13_A2 isolates carry intact and in planta induced Avrblb1, Avrblb2 and Avrvnt1 effector genes that trigger resistance in potato lines carrying the corresponding R immune receptor genes Rpi-blb1, Rpi-blb2, and Rpi-vnt1.1. These findings point towards a strategy for deploying genetic resistance to mitigate the impact of the 13_A2 lineage and illustrate how pathogen population monitoring, combined with genome analysis, informs the management of devastating disease epidemics.