Short-term effects of glyphosate and Roundup Transorb® formulation on the cyanobacteria Synechococcus elongatus

Glyphosate is an active ingredient used in herbicide formulations worldwide. However, besides glyphosate, these formulations have other components to facilitate glyphosate absorption by plants. These include the surfactants such as polyoxyethylene amine (POEA) present in the Roundup Transorb® (RT) formulation. Glyphosate formulations are potentially more toxic to non-target organisms than the pure active ingredient. In this work, we evaluated the toxicity (72 h) of pure glyphosate and RT for the cyanobacterium Synechococcus elongatus, based on biomass growth and cell viability. The formulation proved more toxic than pure glyphosate for both parameters analysed, with an IC50 (Inhibition concentration mean) based on biomass measured by optical density (750 nm) that was sixty times lower. Cell viability was not as sensitive as the biomass because, of the few cells left in the culture, most were viable. This indicates that there is a variation in tolerance between the cyanobacteria present in the inoculum. Thus, cell viability may underestimate the results of glyphosate and RT toxicity and be useful only in low concentrations of exposure

Invertebrados e microbiota associados à degradação de macrófitas aquáticas em um lago raso no sul do Brasil

Aquatic macrophytes are the main producers of organic matter in shallow aquatic ecosystems. They are also food sources for many herbivores. When macrophytes die, they enter the debris chain, are conditioned by microbial action and colonized by benthic invertebrates which remobilize nutrients from their biomass. In subtropical aquatic systems, the participation of shredder invertebrates has been questioned, highlighting the participation of fungi and bacteria in the degradation of organic matter. This study evaluated the degradation of two submerged aquatic macrophytes, Mayaca fluviatilis and Stuckenia pectinata, determining the quality of debris and microbiota and invertebrate trophic group density throughout the degradation process. Our results indicated that plants with lower polyphenol concentrations had higher degradation speeds. The shredders invertebrates had reduced abundance in both macrophytes, emphasizing the importance of bacteria and fungi in the nutrient cycling process in subtropical shallow lakes.Macrófitas aquáticas são os principais produtores de matéria orgânica em ecossistemas aquáticos rasos, sendo fonte alimentar para uma série de herbívoros. Após sua morte, entram na cadeia de detritos, são condicionadas por ação microbiana e colonizados por invertebrados bentônicos, responsáveis pela remobilização dos nutrientes de sua biomassa. Em sistemas aquáticos subtropicais, a participação de invertebrados fragmentadores tem sido questionada, ressaltando a participação de fungos e bactérias na degradação da matéria orgânica. Este trabalho teve como objetivos avaliar a degradação de duas macrófitas aquáticas submersas, determinando a qualidade do detrito e a densidade da microbiota e de grupos tróficos de invertebrados ao longo do processo. Os resultados indicaram que a planta com menor concentração de polifenóis teve velocidade maior de degradação. Os invertebrados fragmentadores tiveram abundância reduzida em ambas macrófitas, ressaltando a importância de bactérias e fungos no processo de ciclagem de nutrientes em lagos rasos subtropicais

NUTRIENT CYCLING IN EUCALYPTUS DUNNII: MICRONUTRIENTS IN THE LITTERFALL

The evaluation of litterfall and nutrient return is important for understanding the dynamics of nutrient cycling. Although required in smaller quantities by plants, micronutrients have unique importance in biogeochemical regulation. The objective of the present study was to quantify the litterfall and the concentration of micronutrients in the different fractions and seasons of the year in Eucalyptus dunnii stand. Four plots of 20 m x 21 m were demarcated. The collection of leaf litter, twigs (diameter 0.5 cm), four useful areas of medium-diameter trees were demarcated in each plot. The leaf fraction represented 59% of litterfall and the transfer order was Mn> Fe> B> Zn> Cu, totaling 8.04 kg ha-1. The leaf fraction presented the highest concentrations for B and Mn. The litterfall was seasonal with summer and spring differing statistically from winter and the temperature variable explains the deposition pattern of the same

HEMANGIOMAS E HEMANGIOSSARCOMAS EM CÃES: ESTUDO RETROSPECTIVO DE 192 CASOS (2002-2014)

O hemangioma e o hemangiossarcoma são neoplasias mesenquimais originárias do endotélio vascular e o cão é o animal doméstico mais frequentemente acometido. Os registros do Laboratório de Patologia Animal do Hospital Veterinário da Universidade Federal de Uberlândia de 2002 a 2014 foram revisados. Os dados epidemiológicos e a frequência de cães com diagnóstico de hemangioma e hemangiossarcoma foram verificados e estatisticamente comparados. Foram identificados 64 casos de hemangioma e 128 casos de hemangiossarcoma. Para os hemangiomas, não houve diferença na frequência de acordo com sexo e raça. Quanto à localização, os hemangiomas não viscerais foram os mais frequentes em relação aos viscerais. As cadelas e animais adultos e idosos foram frequentemente acometidos por hemangiossarcoma, assim como a raça Pitbull. Os hemangiossarcomas apresentaram predominantemente tamanho médio e localização cutânea, ou seja, não visceral. Palavras-chave: cão; endotélio vascular; neoplasia

Analysis Of The Ergosterol Biosynthesis Pathway Cloning, Molecular Characterization And Phylogeny Of Lanosterol 14 α-demethylase (erg11) Gene Of Moniliophthora Perniciosa.

The phytopathogenic fungus Moniliophthora perniciosa (Stahel) Aime & Philips-Mora, causal agent of witches' broom disease of cocoa, causes countless damage to cocoa production in Brazil. Molecular studies have attempted to identify genes that play important roles in fungal survival and virulence. In this study, sequences deposited in the M. perniciosa Genome Sequencing Project database were analyzed to identify potential biological targets. For the first time, the ergosterol biosynthetic pathway in M. perniciosa was studied and the lanosterol 14α-demethylase gene (ERG11) that encodes the main enzyme of this pathway and is a target for fungicides was cloned, characterized molecularly and its phylogeny analyzed. ERG11 genomic DNA and cDNA were characterized and sequence analysis of the ERG11 protein identified highly conserved domains typical of this enzyme, such as SRS1, SRS4, EXXR and the heme-binding region (HBR). Comparison of the protein sequences and phylogenetic analysis revealed that the M. perniciosa enzyme was most closely related to that of Coprinopsis cinerea.37683-9

Quantificação da biomassa e nutrientes em um povoamento de Eucalyptus dunnii Maiden estabelecido no Bioma Pampa

Studies related to biomass production and accumulation of nutrients, are the basis for understanding the nutritional dynamics in forest stands. The objective of this study was to quantify the biomass and nutrient stocks, in a Eucalyptus dunnii stand, at 60 months old, established in Alegrete, Rio Grande do Sul. The sampling of biomass was taken from twelve trees which were cut at soil level and the fractional biomass components: leaf, branches, trunk bark and stem wood, with dry mass determination and nutrients concentration. The total above ground biomass was 58.76 Mg ha-1, with decreasing sequence in the magnitude of the stem wood > trunk bark > branches > leaves. The total stock of nutrients was 175.5; 18.2; 171; 278.1; 69.1 and 21.5 kg ha-1 of N, P, K, Ca, Mg and S, respectively. We emphasize the importance of maintaining of harvest residues in the soil to optimize nutrient cycling due to high levels of these in the leaves, bark and branches.Estudos relacionados à produção de biomassa e acúmulo de nutrientes são a base para a compreensão da dinâmica nutricional em povoamentos florestais. O objetivo do presente trabalho foi quantificar a biomassa e o estoque de nutrientes, em um povoamento de Eucalyptus dunnii, aos 60 meses de idade, estabelecido em Alegrete, Rio Grande do Sul. A amostragem da biomassa foi realizada a partir de doze árvores, que foram seccionadas ao nível do solo e a biomassa foi fracionada nos componentes: folhas, galhos, casca do tronco e madeira do tronco, com determinação de massa seca e tores de nutrientes. A biomassa total acima do solo foi de 58,76 Mg ha-1, com sequência decrescente de alocação em madeira do tronco > casca do tronco > galhos > folhas. O estoque total de nutrientes foi de 175,5; 18,2; 171; 278,1; 69,1 e 21,5 kg ha-1 de N, P, K, Ca, Mg e S, respectivamente. Ressalta-se a importância da manutenção de resíduos da colheita sobre o solo, a fim de otimizar a ciclagem de nutrientes em função dos altos teores destes contidos nas folhas, casca e galhos

Modelling of an Optical Access Network Platform for Radio-Frequency Transmission in the S Band / Modelação de uma Plataforma de Rede de Acesso Óptico para Transmissão de Radiofrequências na Banda S

Microwave transmission in the S Band are used in WiMAX, mobile telephony, air control and satellite communications. Such applications demand the use of wideband optical access networks. In this article, the impact of non-linearities of a fluorescent optical source (FFOS) is analyzed on the performance, at 560 nm, of Discrete-Multitone (DMT) transmissions, using the multicarrier signal-to-noise ratio  (SNRmc) metric. The objective is to provide a  model of SNRmc level curves based on empirical measurements by varying the bias current and the amplitude of the input signal in the optical source. The cartography was approximated by fitting ellipses, which allows us to find an approximate optimum point of operation for the setup.

Effect of freezing and atomization on bioactive compounds in cagaita (Eugenya dysenterica DC) fruit

The aim of this study was to evaluate the effect of freezing and atomization on bioactive compounds in cagaita fruit. The levels of total phenolics, total flavonoids, condensed tannins, vitamin C, β-carotene, the antioxidant potential assessed by DPPH and ABTS, sugar profile, and mineral profile were all evaluated. High levels of total polyphenols (881.95 mg/100 g), total flavonoids (42.93 mg/100 g) and condensed tannins (67.00 mg/100 g) were detected in atomized cagaita pulp. A higher content of vitamin C was found in fresh cagaita pulp (29.75 mg/100 g), compared to frozen pulp, or atomized pulp, which had levels of 24.64 mg/100 g and 20.38 mg/100 g, respectively. Atomized pulp had the highest antioxidant activity as assessed using the ABTS method (517.04 µmol Trolox/g), compared with frozen pulp (357.73 µmol Trolox/g) and fresh cagaita pulp (276.07 µmol Trolox/g). The drying method demonstrated the best performance with respect to fruit preservation

Rice crop detection using LSTM, Bi-LSTM, and machine learning models from sentinel-1 time series

The Synthetic Aperture Radar (SAR) time series allows describing the rice phenological cycle by the backscattering time signature. Therefore, the advent of the Copernicus Sentinel-1 program expands studies of radar data (C-band) for rice monitoring at regional scales, due to the high temporal resolution and free data distribution. Recurrent Neural Network (RNN) model has reached state-of-the-art in the pattern recognition of time-sequenced data, obtaining a significant advantage at crop classification on the remote sensing images. One of the most used approaches in the RNN model is the Long Short-Term Memory (LSTM) model and its improvements, such as Bidirectional LSTM (Bi-LSTM). Bi-LSTM models are more effective as their output depends on the previous and the next segment, in contrast to the unidirectional LSTM models. The present research aims to map rice crops from Sentinel-1 time series (band C) using LSTM and Bi-LSTM models in West Rio Grande do Sul (Brazil). We compared the results with traditional Machine Learning techniques: Support Vector Machines (SVM), Random Forest (RF), k-Nearest Neighbors (k-NN), and Normal Bayes (NB). The developed methodology can be subdivided into the following steps: (a) acquisition of the Sentinel time series over two years; (b) data pre-processing and minimizing noise from 3D spatial-temporal filters and smoothing with Savitzky-Golay filter; (c) time series classification procedures; (d) accuracy analysis and comparison among the methods. The results show high overall accuracy and Kappa (>97% for all methods and metrics). Bi-LSTM was the best model, presenting statistical differences in the McNemar test with a significance of 0.05. However, LSTM and Traditional Machine Learning models also achieved high accuracy values. The study establishes an adequate methodology for mapping the rice crops in West Rio Grande do Sul

PROJETO ACOLHER

O projeto acolher é uma rede de acompanhamento para os acadêmicos dos três primeiros períodos, indígenas e quilombolas do curso de Engenharia Civil, onde busca-se para os ingressantes a promoção e o nivelamento a partir da oferta inicial de um curso de matemática básica a fim de preencher as lacunas de aprendizagem através de aulas presenciais e atividades extra classe para que o discente possa revisar os principais conteúdos expostos no ensino médio com uma visão mais rigorosa e técnica preparando-o para um melhor aproveitamento do curso de engenharia, e o acompanhamento continuado além dos períodos iniciais para os indígenas e quilombolas