149 research outputs found

    Genotypic influence on the absorption and toxicity of manganese in soybean

    Get PDF
    A toxidez de Mn pode ser um problema comum nas regiões tropicais com predominância de solos ácidos. Entretanto, variações das concentrações desse nutriente nas plantas têm sido atribuídas também a diferenças inter e intra-específicas. O presente estudo foi desenvolvido em casa de vegetação e teve como objetivo avaliar as causas de tolerância diferencial à toxidez de Mn. Os cultivares de soja [Glycine max (L.) Merrill] Santa Rosa, IAC-15 e IAC-Foscarin 31 foram cultivados em solução nutritiva (pH 5,0) com cinco doses de Mn (2, 100, 150, 200 e 250 µmol L-1). O delineamento experimental foi o de blocos completos ao acaso em esquema fatorial 5 x 3 (cinco doses de Mn e três cultivares), com três repetições. Os cultivares IAC-15 e Santa Rosa exibiram sintomas visuais de toxidez. As concentrações nas folhas associadas ao excesso foram de 1.000 mg kg-1. Entretanto, o IAC-15 apresentou maior produção de grãos e de matéria seca da parte aérea, acompanhado pelo IAC-Foscarin 31 (intermediário) e Santa Rosa (menor produção). O maior comprimento total de raízes, as maiores produções de matéria seca de raízes e o acúmulo de Mn neste tecido, bem como a maior compartimentalização deste nutriente no apoplasto, conferiram ao IAC-Foscarin 31 maior tolerância ao excesso de Mn na solução. Há, pois, indicações de diferenças genotípicas entre os cultivares e de que vários mecanismos atuam conjuntamente na tolerância ao excesso de Mn em solução.Manganese (Mn) toxicity may be a constraint for crop production in acid soils of tropical regions. However, variations of Mn concentrations in plant tissues are also related to the genotypic differences. A greenhouse experiment was carried out to evaluate Mn tolerance of three soybean cultivars [Glycine max (L.) Merrill]. Cultivars Santa Rosa, IAC-15 and IAC-Foscarin 31 were evaluated under five Mn rates (2, 100, 150, 200, and 250 µmol L-1) in nutrient solution (pH 5.0). The experiment in randomized blocks was a 5 x 3 factorial of five Mn doses and three cultivars, with three replications. IAC-15 and Santa Rosa leaves showed visual symptoms of Mn toxicity. At toxic Mn levels in solution, the average Mn concentration in the leaf blades was close to 1,000 mg kg-1. Nevertheless, grain and dry matter in the aerial parts was higher for IAC-15 than IAC-Foscarin 31 (intermediate yield) and Santa Rosa (lowest yield). The greatest total root length and root dry matter yield, as well as root Mn accumulation and compartmentalization in root apoplast of IAC-Foscarin 31 contributes to explain differences in tolerance to the excess. There are, therefore, indications of genotypic differences among the soybean cultivars and that several mechanisms are involved in the tolerance to high Mn levels.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)FAPESPCNP

    Perdas de nitrogênio por Brachiaria decumbens após a aplicação de glifosato ou glufosinato de amônio

    Get PDF
    Nitrogen losses from the soil-plant system may be influenced by herbicide applications. In order to evaluate N loss in brachiaria (Brachiaria decumbens) after application of the herbicides glyphosate and glufosinate-ammonium, an experiment was carried out in a greenhouse as a completely randomized design, with three treatments and six replicates. Treatments were as follows: i) desiccation of brachiaria-plants with glyphosate; ii) desiccation of brachiaria-plants with glufosinate-ammonium; and iii) control, without herbicide application. The plants were cultivated in 4 kg pots of sandy soil and fertilized with ammonium sulfate- 15N, (200 mg kg-1) in order to quantify the allocation of the fertilizer-N and its recovery in the soil-plant system. Plants treated with the herbicides had less N accumulation and less recovery of the fertilizer-N (15N) relative to the control. In the soil, the greatest recovery of 15N-fertilizer occurred for treatments where N was applied, possibly due to the occurrence of other N compound losses to the soil, like root exudation and root death. The total recovery of 15N-fertilizer in the soil-plant system was higher in the control than in the treated plants showing the direct action of the herbicides on nitrogen loss, and especially by the above-ground part of the brachiaria plants.As perdas de nitrogênio no sistema solo-planta podem ser influenciadas pela aplicação de herbicidas. Com o objetivo de avaliar a perda de N do capim-Brachiaria (Brachiaria decumbens) após a aplicação dos herbicidas glifosato e glufosinato de amônio, foi realizado um experimento em casa-de-vegetação em delineamento inteiramente aleatorizado (DIA), com três tratamentos e seis repetições. Os tratamentos foram os seguintes: i) dessecação de plantas de braquiária com o herbicida glifosato; ii) dessecação de plantas de braquiária com herbicida glufosinato de amônio e iii) testemunha, sem aplicação de herbicida. As plantas foram cultivadas em vasos com 4 kg de solo arenoso e foram fertilizadas com sulfato de amônio (15N), na dose de 200 mg kg-1, com o intuito de quantificar a alocação de N-fertilizante (15N) e sua recuperação no sistema solo-planta. As plantas tratadas com os herbicidas apresentaram menor acúmulo de N e menor recuperação do N-fertilizante (15N) em relação à testemunha. No solo a maior recuperação do 15N-fertilizante ocorreu nos tratamentos em que foram aplicados os herbicidas, possivelmente, devido à ocorrência de perda de compostos nitrogenados para o solo por exsudação radicular e morte de raízes. A recuperação total do 15N-fertilizante no sistema solo-planta foi maior na testemunha que nos tratamentos, evidenciando-se a ação direta dos herbicidas nas perdas de nitrogênio, especialmente, pela parte aérea do capim-Brachiaria

    Nitrogen loss through Brachiaria decumbens after anthesis stage: relation with soil moisture

    Get PDF
    Com o objetivo de avaliar a perda de N por plantas de Brachiaria decumbens no estádio da pós-antese relacionada com a umidade do solo, realizou-se um experimento em casa-de-vegetação, em delineamento inteiramente casualizado, com três tratamentos e seis repetições. Os tratamentos do estudo constaram da colheita de plantas nos seguintes estádios e condições de umidade do solo: (a) A60: estádio de antese e com umidade do solo mantida a 60% da capacidade máxima de retenção de água; (b) PA60: estádio de pós-antese ou maturidade com umidade do solo mantida a 60% da capacidade máxima de retenção de água; e (c) PA20: pós-antese com umidade estabelecida após a antese de 20% da capacidade máxima de retenção de água do solo. As plantas de Brachiaria decumbens, cultivadas em vasos preenchidos com solo arenoso, foram fertilizadas com sulfato de amônio-15N (800mg vaso-1 de N). As plantas dos tratamentos pós-antese (PA60 e PA20) foram colhidas após 17 dias do início do florescimento. O balanço de N do sulfato de amônio (15N) no sistema solo-planta indicou perdas de N, presumivelmente pela parte aérea das plantas de Brachiaria decumbens, no estádio de pós-antese (tratamento PA60), da ordem de 25% em relação ao de antese (A60). A perda de N na pós-antese avaliada no tratamento com déficit hídrico (PA20) foi reduzida comparativamente ao PA60, sendo da ordem de 11% em relação ao tratamento A60.The objective of this research work was to evaluate the N loss through Brachiaria decumbens in the stage of post-anthesis related to the soil moisture. The experiment was carried out in green-house condition and the experimental design was a completely randomized, with three treatments and six replications. Plants of grass-Brachiaria were cultivated in pots filled out with sandy soil. The soil of each pot was fertilized with ammonium sulfate-15N (800mg vaso-1 of N). The treatments consisted of harvest of plants in the stages and soil moisture conditions, as following: (a) A60: stage of anthesis and with soil moisture maintained to 60% of the maximum water retention capacity; (b) PA60: post-anthesis stage or maturity with soil moisture maintained to 60% of the maximum retention capacity, and (c) PA20: post-anthesis stage with soil moisture of 20% of the maximum water retention capacity established after the anthesis stage. The plants of the treatments post-anthesis (PA60 and PA20) were harvested after 17 days beginning of the flowering stage. The balance of N from ammonium sulfate (15N) in the soil-plant system indicated losses of N, presumably from the aerial part of grass-Brachiaria plants in the post-anthesis stage (treatment PA60). These values were of the order of 25% in relation to the anthesis treatment (A60). The N loss in the post-anthesis stage as evaluated in the treatment with water deficits (PA20), it was minimized comparatively to the PA60 and it was of the order of 11% in relation to the treatment A60

    Productivity and mortality, of Fusarium oxysporum f. sp. passiflorae in passionfruit vines brs rubi do cerrado, grafted onto different rootstocks

    Get PDF
    The use of scions grafted onto passionfruit vines has become an alternative to their cultivation in areas with a history of fusariosis. However, the combinations between the graft and rootstock can influence on the productivity and longevity of the passionfruit farm. The objective was to evaluate the productivity and mortality of the passionfruit cv BRS Rubi do Cerrado grafted onto three species of rootstock in Terra Nova do Norte-MT. The design was a randomized block with 4 treatments BRS Rubi do Cerrado (BRS-RC) seedling plant along with those grafted onto three species of rootstock: Passiflora gibertii, Passiflora alata; Passiflora nitida. The scions were grafted through a cleft graft and the planting performed after 70 days. The evaluation was made of the total number and weight of the fruits, along with productivity and mortality of plants. Results showed that the BRS-RC, grafted onto P. gibertii and P. nitida, presented the best performance for weight of fruits, number of fruits and productivity. The cultivar that was grafted onto different rootstocks presented higher productivity in regards to the seedling plant. The BRS-RC, grafted onto P. nitida, presented a zero-mortality rate over the 16.5 months of cultivation. The rootstocks P. nitida and P. gibertii were superior to those of P. alata in reducing mortality in the passionfruit vine by Fusarium oxysporum f. sp. passiflorae. The confirmation was made of the pathogen Fusarium oxysporum f. passiflorae isolated in the experimental area in scions of the BRS-RC inoculated at 70 days of age

    The Photopic Negative Response: An Objective Measure of Retinal Ganglion Cell Function in Patients With Leber's Hereditary Optic Neuropathy

    Get PDF
    Purpose: The photopic negative response (PhNR) is a slow negative component of a flash photopic full-field ERG that has been shown to be specific for retinal ganglion cell (RGC) activity. Direct evaluation of RGC function is desirable in patients with Leber's hereditary optic neuropathy (LHON) in which the loss of central acuity can make it difficult to monitor patients with standard metrics. The purpose of this study was to evaluate the use of PhNR as an objective noninvasive clinical metric in LHON.Methods: Full-field photopic ERG recordings were collected in subjects with the mt.11778G>A/ND4 LHON mutation using a red on blue stimulus. The PhNR was identified using a computer-based automated detection system, and data were manually examined to remove movement artifacts.Results: The PhNR amplitude was compared between controls (n = 13), carriers (n = 17), and affected (n = 6). Mean PhNR amplitude decreased significantly across groups (P < 0.0001). Post hoc Tukey's test revealed a significant decrease in PhNR amplitude between carriers and controls (P < 0.05) and between carriers and affected (P < 0.01).Conclusions: We are able to demonstrate that the PhNR amplitude is significantly decreased in patients affected by LHON compared to carriers in a well-described pedigree. Surprisingly, there was also a decrease in PhNR in carriers, suggesting potential subclinical RGC dysfunction in some carriers. This is important in patients affected with LHON who typically have a dense central scotoma. The PhNR may be a useful objective outcome measure for future clinical trials

    Response of greenhouse grown rice plant to sources of micronutrients with different granulometry and solubility

    Get PDF
    A granulometria e a solubilidade do fertilizante podem resultar em maior ou menor efeito da adubação. O objetivo deste trabalho foi comparar o efeito de um produto comercial granulado e moído de micronutrientes, com uma mistura de igual composição feita com materiais pró-análise. O delineamento experimental foi o inteiramente casualizado, utilizando três produtos com micronutrientes e quatro doses de cada mistura (0, 14, 28 e 56 mg dm-3), com quatro repetições. A maior produção de grãos é obtida com a aplicação do produto comercial em pó. A melhor correlação entre os materiais e teor na planta ocorre em razão do zinco.Both granulometry and solubility could affect the response of a crop to fertilizer application. The objective of this work was to compare the effect of a commercial source of micronutrients, in granular and powder form, with a mixture of pro analyse products. A completely randomized design, with three products, four replicates and four rates (0, 14, 28 and 56 mg dm-3 of soil) were used. The highest grain yield was due to the commercial product in powder form. Positive correlation was found between plant Zn and its content in the products

    Inversão da pirâmide alimentar em adolescentes praticantes de treinamento resistido: um estudo piloto

    Get PDF
    Objetivo: avaliar o consumo alimentar de adolescentes praticantes de treinamento resistido ao longo de 12 semanas e sua possível influência na composição corporal. Materiais e métodos: Fizeram parte da amostra 12 sujeitos de ambos os sexos, com média de idade 17,17 anos ± 0,72. A composição corporal foi mensurada utilizando o software Terra Azul da Physical Test® versão 4.21 no qual a predição de gordura de foi feita de acordo com o protocolo de Pollock de sete dobras (pré e pós-treinamento resistido). O comportamento alimentar foi avaliado por meio do Questionário de Frequência de Consumo Alimentar - QFCA. Resultados: Os achados do nosso estudo mostraram que no período de 12 semanas de TR não houve modificação na composição corporal dos adolescentes, a estatura média foi de 1,67 m ± 0,08; da massa corporal foi de 59,87 kg ± 10,79; e do percentual de gordura de 19,62% ± 4,66; percentual da massa livre de gordura de 80,38% ± 4,66 (P&gt;0,05). Além disso, a avaliação do estado nutricional apontou que a maioria dos adolescentes está com o consumo “abaixo do ideal†para os grupos alimentares da base da PA e “acima do ideal†para os grupos alimentares do ápice (P&lt;0,05), caracterizando uma inversão da recomendação do consumo alimentar. Conclusão: o treinamento resistido isoladamente não foi capaz de alterar a composição corporal de adolescentes após 12 semanas de treinamento, se os mesmos, não possuírem supervisão direta da dieta e treino.  ABSTRACTFood pyramid inversion in resistence training exerciser teenagers: a pilot studyObjective: this paper intended to evaluate the food intake habits of teenagers who practiced resistance training exercises and its influence on body composition during 12 weeks. Methods: a study of 12 male and female teenagers with the average age 17.17 ± 0.72 yr. The body composition was evaluated by Terra Azul software (Physical Test®, version 4.21), through the Pollock protocol (7 skin folds), before and after resistance training. The food intake habits were assessed by Food Consumption Frequency Questionnaire – QFCA. Results:  during 12 weeks of resistance training there was no difference on teenager’s anthropometry. The average height was 1.67 ± 0.08m; body weight 59.87 ± 10.79 kg; body fat 19.62% ± 4.66; fat-free mass 80.38% ± 4.66 (P&gt;0.05). Moreover, the nutrition status evaluation showed that teenagers had “below-ideal†consumption of the base food groups from the food pyramid and “above-ideal†of the apex food groups from the food pyramid (P&gt;0.05), which characterized a food pyramid inversion. Conclusion: the resistance training per se wasn’t able to modify teenagers’ body composition after 12 weeks of resistance training

    Reconhecimento de ações judiciais relacionadas ao consumo de energia não registrado utilizando engenharia de características de relacionamento temporalizadas e rede LSTM/ Recognition of lawsuits related to unregistered energy consumption using temporalized relationship characteristics engineering and LSTM network

    Get PDF
    O grande número de ações judiciais contra empresas de distribuição de energia destaca o difícil problema de identificar e solucionar falhas de serviços neste setor. Este trabalho propõe uma metodologia para identificar novas ações judiciais no setor de energia baseado em informações do relacionamento cliente com a companhia, além da identificação de fatores correlacionados. A metodologia é basicamente dividida em 4 etapas: (a) aquisição de dados; (b) engenharia de características; (c) seleção de características; e (d) classificação usando LSTM. O método foi realizado em um banco de dados com mais de cinquenta mil consumidores e mostra-se robusto na tarefa de identificar a predição de ações judiciais de consumo de energia não registrada por meio de uma acurácia de 92,89%; especificidade de 94,27%; sensibilidade de 88,79%; e precisão de 83,84%. Assim, demonstra-se a viabilidade de usar o LSTM para resolver o problema da predição de processos judiciais de consumo de energia não registrados

    Tele-electrocardiography and bigdata: the CODE (Clinical Outcomes in Digital Electrocardiography) study

    Get PDF
    Digital electrocardiographs are now widely available and a large number of digital electrocardiograms (ECGs) have been recorded and stored. The present study describes the development and clinical applications of a large database of such digital ECGs, namely the CODE (Clinical Outcomes in Digital Electrocardiology) study. ECGs obtained by the Telehealth Network of Minas Gerais, Brazil, from 2010 to 17, were organized in a structured database. A hierarchical free-text machine learning algorithm recognized specific ECG diagnoses from cardiologist reports. The Glasgow ECG Analysis Program provided Minnesota Codes and automatic diagnostic statements. The presence of a specific ECG abnormality was considered when both automatic and medical diagnosis were concordant; cases of discordance were decided using heuristisc rules and manual review. The ECG database was linked to the national mortality information system using probabilistic linkage methods. From 2,470,424 ECGs, 1,773,689 patients were identified. After excluding the ECGs with technical problems and patients &lt;16 years-old, 1,558,415 patients were studied. High performance measures were obtained using an end-to-end deep neural network trained to detect 6 types of ECG abnormalities, with F1 scores &gt;80% and specificity &gt;99% in an independent test dataset. We also evaluated the risk of mortality associated with the presence of atrial fibrillation (AF), which showed that AF was a strong predictor of cardiovascular mortality and mortality for all causes, with increased risk in women. In conclusion, a large database that comprises all ECGs performed by a large telehealth network can be useful for further developments in the field of digital electrocardiography, clinical cardiology and cardiovascular epidemiology

    Ticks as potential vectors of Mycobacterium leprae: Use of tick cell lines to culture the bacilli and generate transgenic strains.

    Get PDF
    Leprosy is an infectious disease caused by Mycobacterium leprae and frequently resulting in irreversible deformities and disabilities. Ticks play an important role in infectious disease transmission due to their low host specificity, worldwide distribution, and the biological ability to support transovarial transmission of a wide spectrum of pathogens, including viruses, bacteria and protozoa. To investigate a possible role for ticks as vectors of leprosy, we assessed transovarial transmission of M. leprae in artificially-fed adult female Amblyomma sculptum ticks, and infection and growth of M. leprae in tick cell lines. Our results revealed M. leprae RNA and antigens persisting in the midgut and present in the ovaries of adult female A. sculptum at least 2 days after oral infection, and present in their progeny (eggs and larvae), which demonstrates the occurrence of transovarial transmission of this pathogen. Infected tick larvae were able to inoculate viable bacilli during blood-feeding on a rabbit. Moreover, following inoculation with M. leprae, the Ixodes scapularis embryo-derived tick cell line IDE8 supported a detectable increase in the number of bacilli for at least 20 days, presenting a doubling time of approximately 12 days. As far as we know, this is the first in vitro cellular system able to promote growth of M. leprae. Finally, we successfully transformed a clinical M. leprae isolate by inserting the reporter plasmid pCHERRY3; transformed bacteria infected and grew in IDE8 cells over a 2-month period. Taken together, our data not only support the hypothesis that ticks may have the potential to act as a reservoir and/or vector of leprosy, but also suggest the feasibility of technological development of tick cell lines as a tool for large-scale production of M. leprae bacteria, as well as describing for the first time a method for their transformation
    corecore