264 research outputs found
Eficiência comparada da aplicação radicular e foliar de macro e micronutrientes para a correção de deficiências minerais no arroz (Oryza sativa L.)
Rice plants cultivars IAC 47 (upland) an IAC 435 (lowland) were grown in nutrient solution either under low levels of N, P, K or S, or in the absence of B, Cu or Zn. At the tillering stage the deficient element was supplied via nutrient solution or through leaf feeding. Yield data and leaf analyses allowed for the following general conclusions to be drawn: (1) the deficiency of a given element affected differently grain production in the two varieties; (2) for a given nutrient the same nutritional status, i.e., "normal" or "deficient" could be defined by different leaf levels; (3) additional yield (due to corrective measures) divided by quantity of element applied was higher in the case of foliar feeding of macronutrients; the opposite took place in the case of micronutrients.Deficiências de N, P, K, S, B, Cu ou Zn foram induzidas em dois cultivares de arroz, I.A.C. 47 e I.A.C. 435 até o perfilhamento. O elemento deficiente foi depois aplicado na solução nutritiva ou por via foliar. A eficiência dos tratamentos foi avaliada dividindo-se o peso adicional de grãos pela quantidade de elemento fornecida pelos dois métodos. Verificaram-se, de modo geral, relações maiores no caso da adubação foliar que da radicular, em se tratando de macronutrientes; o oposto foi observado quando se tratava de micronutrientes
Exigências nutricionais do arroz (Oryza sativa L., cv. IAC 47 e IAC 435)
Analysing the various organs of plants grown in nutrient solution until full maturity, an estimate was obtained of the mineral requirements of both cultivars, which in shown in Table 4. Differences found among cultivars were due primarily to yield level rather than to contents of elements per unity of dry matter.Analisando-se os diferentes órgãos de plantas de arroz cultivada em solução nutritiva até maturidade completa, foi obtida uma estimativa das exigências nutricionais dos cultivares IAC 47 (sequeiro) e IAC 435 (irrigado). As diferenças encontradas entre os dois cultivares são de vidas principalmente ao nível de produção e não ao teor de elemento na matéria seca
Nota sobre o cultivo do arroz (Oryza sativa L.), cv. IAC 47 e IAC 435 em solução nutritiva
As soluções nutritivas de HOAGLAND & ARNON (1950) nº 2 de KARIM & VLAMIS (1962) foram fornecidas a duas variedades de arroz, uma de sequeiro (IAC 47) e uma de irrigação (IAC 435). A primeira solução, que contém N nítrico e N amoniacal, garantiu maior produção de matéria seca e maior teor de N total nas plantas que foram colhidas no meio do estádio de perfilhamento. A aeração forçada mostrou-se desnecessária para o crescimento.In a preliminary trial, a comparison was made of two nutrient solutions, HOAGLAND & ARNON (1950) number 2, and KARIM & VLAMIS (1962), both in the presence and in the absence of forced aeration. Plants grown during 40 days (till the middle of the tillering stage) showed a higher dry matter yield as well as a higher N content when receiving the first solution, which contains both nitrate and ammonium N, when compared with the latter whose nitrogen is only in the NO-3form. Aeration was not necessary for maximum growth in either case
On the viability of correcting mineral deficiencies induced in the rice plant
Plants were grown in nutrient solution under conditions of deficiency of N, P, K, S, B, Cu or Zn till the stage of tillering. An attempt was then made to ascertain the extent of correction of the deficiencies by supplying the element lacking in the substrate either in the nutrient solution or through foliar application, The results of the corrective tratments are presented in Table 15 in which yield data are given as percentage of those obtained with the non deficient plants.Plantas de arroz dos cultivares IAC 47 (sequeiro) e IAC 435 (de irrigação) foram cultivadas em solução nutritiva deficiente em N, P, K, S, B, Cu ou Zn até o estádio de perfilhamento. O elemento em falta foi, então, for necido por via radicular ou foliar na tentativa de correção da deficiência. Foram notadas, em termos de produção de grãos, respostas diferentes em funcão de: cultivar, elemento aplicado e modo de aplicação
Nível crítico de fósforo em cultivares de algodão: II. Escolha do órgão adequado para determinação do nível crítico
In order to establish the critical level of phosphorus in annual varieties IAC-20, IAC-19, IAC-17, CNPA 78/SME-4 and in perennial varieties CNPA 2M and CNPA 3M young cotton plants were grown in nutrient solutions containing the following phosphorus concentrations: 0.38ppm, 1.14ppm, 3.42ppm, 10.26ppm and 30.78ppm. The solutions were replaced every seven days. From plants at the age of 44 days, 59 days and 74 days, the 5th leaf from the apex of the plants were collected and separated into petioles and leave blades and the phosphorus content was determined. The authors concluded: - The petioles or leave blades are adequate for the determination of the critical level of phosphorus.Com o intuito de se obter o nível crítico de fósforo para as cultivares de ciclo anual, IAC-20, IAC-19, IAC-17 e CNPA 78/SME4 e para as de ciclo perene CNPA 2M e CNPA 3M foi conduzido experimento em ca-sa-de-vegetaçao com solução nutritiva. As plantas foram cultivadas em quatro níveis de fósforo, sendo: l,14ppm, 3,42ppm, 10,26ppm e 30,78ppm. Em plantas com 44 dias, 59 dias e 74 dias foi coletada a 5ª folha situada no caule principal, a partir do ápice, e dividida em limbo, o pecíolo para a determinação de fósforo. Os níveis críticos internos de fósforo no limbo e pecíolo que correspondem à produção máxima de matéria seca em cada cultivar, foram determinados. Os autores concluem: - O limbo e/ou o pecíolo são adequados para a determinação do nível crítico de fósforo de todas as cultivares
Efeitos alelopáticos de algumas leguminosas e gramíneas sobre a flora invasora
The alellopathic effects produced by five vegetables species: Avena sativa L., Lolium multiflorum Lam., Vicia sp., Medicago sativa L. and Trifolium repens L. were studied as to their effect on weeds. Individual plots were prepared, fertis. A high weed incidence was noted in the plots of Trifolized and sowed according to the usual recomendationlium repens L. and Medicago sativa L.; in the plots of Avena sativa L. and Lolium multiflorum Lam. , few weed specimens were found; the plot of Vicia sp. maintained an intermediate position. Based on the data obtained it is possible to recommend the two grass species as alellopathic plants to cover the soil. Vicia sp. is indicated when besides the reduction of weed plants, organic matter is desired for incorporation.Foram estudados os efeitos alelopáticos produzidos por cinco espécies vegetais: as gramíneas Avena sativa L., e Lolium multiflorum Lamb.; e as leguminosas Vicia sp., Mediaago sativa L. e Trifolium repens L. Canteiros isolados foram preparados, adubados e semeados de acordo com as recomendações técnicas usuais. Nos resultados obtidos observou-se alta incidência de invasoras nos canteiros de Trifolium repens L. e Medicago sativa L., contrastando com os canteiros de Avena sativa L. e Lolium multiflorum Lamb., onde poucas foram as espécies encontradas; enquanto o canteiro de Vicia sp. manteve posição intermediária. Com base nos dados obtidos, pode-se recomendar as duas gramíneas como cultura de cobertura com propriedades alelopáticas, assim como a Vicia sp. quando desejar-se além da redução das plantas invasoras, matéria orgânica para incorporação
Histopathological features of the brain extracellular matrix from dogs with canine distemper
ABSTRACT Canine distemper causes demyelinating leucoencephalitis, like human multiple sclerosis. The encephalic microenvironment, including the extracellular matrix, is an important key factor of this lesion, already described in multiple sclerosis but not proved in canine distemper. Thereby, the aim of this work is to characterize the extracellular matrix in the encephalon of dogs with canine distemper. Samples of cortex and cerebellum of 14 naturally infected dogs with canine distemper virus were collected after being sent for necropsy in the Animal Pathology Laboratory of the Veterinary Hospital of Uberlândia Federal University. The samples were processed as routine, stained with Hematoxylin and Eosin (H.E), Masson Trichrome (MT), Periodic Acid-Schiff (PAS) and Reticulin, and then described. Areas of demyelination and necrosis were quantified in percentage of stain. The TM samples showed blue stain around vessels and meninge, which indicates a higher deposition of collagen in lesioned areas. At necrotic areas, reticulin stain pointed to a disorganization in the vascular wall and PAS-stained pink granules in macrophages. We conclude that the extracellular matrix seems to participate in the pathogeny of canine distemper. More research should be done to better detail the involvement of these molecules in the course of this disease
Um Interior Vazio: A análise da situação dos municípios do COREDE Fronteira Noroeste
Um dos fatores que influenciam o desenvolvimento local é a dinâmica populacional. O deslocamento de pessoas para uma determinada área está relacionado com o comportamento da economia e, a análise das conexões entre migração e desenvolvimento se torna pertinente. O Conselho Regional de Desenvolvimento (COREDE) Fronteira Noroeste é o objeto desta pesquisa devido à evasão populacional que se verifica em seu território, sobretudo nos municípios de menor porte. Esta investigação busca despertar uma reflexão sobre as causas e as soluções para este problema de modo que, o aprofundamento deste estudo contribui para o entendimento dos movimentos migratórios e o desenvolvimento. One of the factors that influence local development is the population dynamics. The movement of people to a particular area is related to the behavior of the economy and the analysis of the links between migration and development becomes relevant. The Regional Development Council (COREDE) North West Frontier is the object of this research due to the decline in population that occurs in its territory, particularly in smaller municipalities. This research seeks to arouse a reflection on the causes and solutions to this problem so that the deepening of this study contributes to the understanding of migration and development
BRST approach to Lagrangian formulation for mixed-symmetry fermionic higher-spin fields
We construct a Lagrangian description of irreducible half-integer higher-spin
representations of the Poincare group with the corresponding Young tableaux
having two rows, on a basis of the BRST approach. Starting with a description
of fermionic higher-spin fields in a flat space of any dimension in terms of an
auxiliary Fock space, we realize a conversion of the initial operator
constraint system (constructed with respect to the relations extracting
irreducible Poincare-group representations) into a first-class constraint
system. For this purpose, we find auxiliary representations of the constraint
subsuperalgebra containing the subsystem of second-class constraints in terms
of Verma modules. We propose a universal procedure of constructing
gauge-invariant Lagrangians with reducible gauge symmetries describing the
dynamics of both massless and massive fermionic fields of any spin. No
off-shell constraints for the fields and gauge parameters are used from the
very beginning. It is shown that the space of BRST cohomologies with a
vanishing ghost number is determined only by the constraints corresponding to
an irreducible Poincare-group representation. To illustrate the general
construction, we obtain a Lagrangian description of fermionic fields with
generalized spin (3/2,1/2) and (3/2,3/2) on a flat background containing the
complete set of auxiliary fields and gauge symmetries.Comment: 41 pages, no figures, corrected typos, updated introduction, sections
5, 7.1, 7.2 with examples, conclusion with all basic results unchanged,
corrected formulae (3.27), (7.138), (7.140), added dimensional reduction part
with formulae (5.34)-(5.48), (7.8)-(7.10), (7.131)-(7.136), (7.143)-(7.164),
added Refs. 52, 53, 54, examples for massive fields developed by 2 way
Molecular detection and phylogenetic relationship of wild-type strains of canine distemper virus in symptomatic dogs from Uberlândia, Minas Gerais
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