51 research outputs found
Trichoderma spp. on treatment of Handroanthus serratifolius seeds: effect on seedling germination and development
Fungi of the genus Trichoderma are important microorganisms used in biocontrol processes and the promotion of plant development. However, they remain poorly studied in the context of forestry programs, especially those related to native Amazonian species. Thus, it is the aim of this study to evaluate the effects of different Trichoderma isolates on the germination and development of Handroanthus serratifolius seedlings. During in vitro germination tests, seeds were immersed for 24 h in respective fungal suspensions each prepared using one of five Trichoderma isolates. The suspensions were held in plastic trays and kept at a temperature of 24 ± 2 °C. Metrics related to germination and development assessed under laboratory conditions include: germination speed index (GSI), germination percentage, length of the roots, and hypocotyls, as well as fungal perseverance. In the nursery, Trichoderma were used in two different applications: pre-planting treatment and as a monthly, post-planting treatment. Pre-planting treatments consisted of 10 g of colonized rice grains bearing each isolate being placed into experimental bags five days before seeding. The post-planting treatment involved the application of 10 mL of fungal suspension per experimental bag. Each month, the height, stem diameter, and leaf number were measured for each seedling. At the end of the experiment, the length and mass of roots as well as the total dry mass were recorded. In laboratory conditions, seeds treated with Trichoderma asperellum -TAM03 obtained the greatest fractional germination (76.5%) and GSI. In the nursery experiments, isolates TAM01 and TAM03, when applied as a post-planting treatment, increased the height, stem diameter, and number of leaves of treated plants with respect to the control group by 180 days post-treatment. After 365 days, plants which received TAM01 pre-planting treatments were observed to have increased root and aerial part length, as well as root mass and overall dry mass. These results suggest that T. asperellum -TAM01 positively affects H. serratifolius development.Institutional Scientific Initiation Scholarship Program (PIBIC/UFOPA)info:eu-repo/semantics/publishedVersio
Evolutionary Patterns of the Mitochondrial Genome in Metazoa: Exploring the Role of Mutation and Selection in Mitochondrial Protein–Coding Genes
The mitochondrial genome is a fundamental component of the eukaryotic domain of life, encoding for several important subunits of the respiratory chain, the main energy production system in cells. The processes by means of which mitochondrial DNA (mtDNA) replicates, expresses itself and evolves have been explored over the years, although various aspects are still debated. In this review, we present several key points in modern research on the role of evolutionary forces in affecting mitochondrial genomes in Metazoa. In particular, we assemble the main data on their evolution, describing the contributions of mutational pressure, purifying, and adaptive selection, and how they are related. We also provide data on the evolutionary fate of the mitochondrial synonymous variation, related to the nonsynonymous variation, in comparison with the pattern detected in the nucleus
Managing complexity through abstraction: A refinementbased approach to formalize instruction set architectures
Abstract. Verifying the functional correctness of a processor requires a sound and complete specification of its Instruction Set Architecture (ISA). Current industrial practice is to describe a processor’s ISA informally using natural language often with added semi-formal notation to capture the functional intent of the instructions. This leaves scope for errors and inconsistencies. In this paper we present a method to specify, design and construct sound and complete ISAs by stepwise refinement and formal proof using the formal method Event-B. We discuss how the automatically generated Proof Obligations help to ensure self-consistency of the formal ISA model, and how desirable properties of ISAs can be enforced within this modeling framework. We have developed a generic ISA modeling template in Event-B to facilitate reuse. The key value of reusing such a template is increased model integrity. Our method is now being used to formalize the ISA of the XMOS XCore processor with the aim to guarantee that the documentation of the XCore matches the silicon and the silicon matches the architectural intent.
Electric telegraphy in the pages of “O Instituto”, Journal of Coimbra’s Academy
Analisamos os avanços da telegrafia eléctrica e da telegrafia sem fios no mundo e, em particular, em Portugal, com base em artigos da revista O Instituto, publicada pelo Instituto de Coimbra, uma sociedade científica, fundada em 1852, que reuniu um vasto leque de personalidades das ciências e artes nacionais. Passamos em revista os principais artigos sobre a telegrafia: o artigo de José Maria de Abreu de 1855, publicado menos de um mês depois da adjudicação das primeiras linhas telegráficas em Portugal; o parecer da Faculdade de Filosofia da Universidade de Coimbra sobre as deliberações do Congresso e Conferências de Paris para determinação das unidades eléctricas, onde esteve Santos Viegas, Presidente do Instituto; e o artigo de Álvaro Silva Basto de 1903 sobre a telegrafia sem fios. Uma menção especial é feita ao artigo de Adriano Paiva Brandão de 1878 sobre telescopiaWe analyze the advances of electric telegraphy and of wireless telegraphy in the world and, in particular, in Portugal, based on articles of the periodical O Instituto, published by the Instituto de Coimbra, a scientific society, founded in 1852, that gathered many Portuguese personalities of science and arts. We review the main articles on telegraphy: the paper by José Maria de Abreu in 1855, less than a month after the adjudication of the first telegraphic lines in Portugal; the assessment by the Philosophical Faculty of the University of Coimbra on the deliberations of the Congress and Conferences of Paris for the unification of electric units, where Santos Viegas, the President of the Coimbra's Institute was present; and the paper of Álvaro Silva Basto in 1903 on wireless telegraphy. Special mention is made to the article by Adriano Paiva Brandão in 1978 on telescop
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