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

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

BRST approach to Lagrangian construction for fermionic higher spin fields in AdS space

We develop a general gauge invariant Lagrangian construction for half-integer higher spin fields in the AdS space of any dimension. Starting with formulation in terms of auxiliary Fock space we derive the closed nonlinear symmetry algebras of higher spin fermionic fields in the AdS space and find the corresponding BRST operator. A universal procedure of constructing the gauge invariant Lagrangians describing the dynamics of fermionic fields of any spin is developed. No off-shell constraints for the fields and gauge parameters are imposed from the very beginning. It is shown that all the constraints determining the irreducible representation of the AdS group arise as a consequence of the equations of motion and gauge transformations. As an example of the general procedure, we derive the gauge invariant Lagrangians for massive fermionic fields of spin 1/2 and 3/2 containing the total set of auxiliary fields and gauge symmetries.Comment: Minor changes. Version accepted for publication in NP

On the influence of a Coulomb-like potential induced by the Lorentz symmetry breaking effects on the Harmonic Oscillator

In this work, we obtain bound states for a nonrelativistic spin-half neutral particle under the influence of a Coulomb-like potential induced by the Lorentz symmetry breaking effects. We present a new possible scenario of studying the Lorentz symmetry breaking effects on a nonrelativistic quantum system defined by a fixed space-like vector field parallel to the radial direction interacting with a uniform magnetic field along the z-axis. Furthermore, we also discuss the influence of a Coulomb-like potential induced by Lorentz symmetry violation effects on the two-dimensional harmonic oscillator.Comment: 14 pages, no figure, this work has been accepted for publication in The European Physical Journal Plu

Relativistic quantum dynamics of a charged particle in cosmic string spacetime in the presence of magnetic field and scalar potential

In this paper we analyze the relativistic quantum motion of charged spin-0 and spin-1/2 particles in the presence of a uniform magnetic field and scalar potentials in the cosmic string spacetime. In order to develop this analysis, we assume that the magnetic field is parallel to the string and the scalar potentials present a cylindrical symmetry with their center on the string. Two distinct configurations for the scalar potential, $S(r)$, are considered: $(i)$ the potential proportional to the inverse of the polar distance, i.e., $S\propto1/r$, and $(ii)$ the potential proportional to this distance, i.e., $S\propto r$. The energy spectra are explicitly computed for different physical situations and presented their dependences on the magnetic field strength and scalar coupling constants.Comment: New version with 20 pages and no figure. Some minor revisions and six references added. Accepted for publication in EJP

Avaliação da incidência de antracnose, do desempenho e estado nutricional de variedades de mangueira, para cultivo orgânico, na região centro-norte do Estado de São Paulo.

A mudança do perfil do consumidor, aliada aos riscos da contaminação por agrotóxicos, tem levado à busca de alternativas ecologicamente apropriadas para produção de frutas. Os objetivos deste trabalho foram avaliar a incidência de antracnose, o desempenho e estado nutricional de variedades de mangueira conduzidas organicamente na região de Pindorama-SP. Foram utilizadas 17 variedades de mangueira. O experimento foi instalado em delineamento experimental em blocos completos ao acaso, com 17 tratamentos (variedades) e seis repetições. Foi avaliada a severidade de antracnose nas folhas, através de uma escala diagramática, atribuindo-se notas aos sintomas. Foram avaliados o crescimento e o desenvolvimento (altura da planta, perímetro do tronco e da copa) e o estado nutricional, mediante análise foliar, das diferentes variedades utilizadas. Através dos resultados obtidos, podem-se considerar como muito suscetíveis à antracnose as variedades Bourbon, Rocha e Rosa; e resistentes, as variedades IAC 111, Alfa, Beta e Parvin; as variedades de manga apresentaram o mesmo padrão de crescimento; as maiores alturas da planta corresponderam aos maiores diâmetros do tronco e da copa; a variedade Parvin apresentou o melhor desempenho dentre as variedades estudadas, com relação à resistência à antracnose, altura e diâmetro do caule e da copa, podendo ser recomendada ao cultivo orgânico. As variedades Omega e Alfa também apresentaram bom crescimento, podendo ser indicadas para esse cultivo, pelo menos nessa fase inicial; as variedades Surpresa e Rosa não apresentaram bom desempenho, no campo, em relação às demais, não devendo ser recomendadas para o cultivo orgânico, principalmente a variedade Rosa, bastante suscetível à antracnose. As concentrações de N, P e K foram elevadas na fase vegetativa das plantas, comparadas à baixa concentração de Ca; houve carência de Boro em todas as variedades estudadas. A manga Rosa, provavelmente, sofreu toxicidade ao excesso de manganês, ocasionando diminuição em seu desenvolvimento