3,948 research outputs found
Pragas do melao e alternativas de controle.
Mosca branca; Brocas das cucurbitaceas; Pulgão; Moscas das frutas; Mosca minadora; Lagarta rosada; Vaquinha.bitstream/item/136248/1/ID-8813.pdfApostila do I Curso sobre o Cultivo do Melao, 2000, Petrolina
News for assimilation or integration?:Examining the functions of news in shaping acculturation experiences of immigrants in the Netherlands and Spain
Semiclassical asymptotic behavior of orthogonal polynomials
Our goal is to find asymptotic formulas for orthonormal polynomials
with the recurrence coefficients slowly stabilizing as .
To that end, we develop spectral theory of Jacobi operators with long-range
coefficients and study the corresponding second order difference equation. We
suggest an Ansatz for its solutions playing the role of the semiclassical
Green-Liouville Ansatz for solutions of the Schr\"odinger equation. The
formulas obtained for as generalize the classical
Bernstein-Szeg\"o asymptotic formulas
Object orientation without extending Z
The good news of this paper is that without extending Z,
we can elegantly specify object-oriented systems, including encapsulation,
inheritance and subtype polymorphism (dynamic dispatch). The
bad news is that this specification style is rather different to normal
Z specifications, more abstract and axiomatic, which means that it is
not so well supported by current Z tools such as animators. It also enforces
behavioural subtyping, unlike most object-oriented programming
languages. This paper explains the proposed style, with examples, and
discusses its advantages and disadvantages
On the Selection of Photometric Planetary Transits
We present a new method for differentiating between planetary transits and
eclipsing binaries based on the presence of the ellipsoidal light variations.
These variations can be used to detect stellar secondaries with masses ~0.2
M_sun orbiting sun-like stars at a photometric accuracy level which has already
been achieved in transit surveys. By removing candidates exhibiting this effect
it is possible to greatly reduce the number of objects requiring spectroscopic
follow up with large telescopes. Unlike the usual candidate selection method,
which are primarily based on the estimated radius of the orbiting object, this
technique is not biased against bona-fide planets and brown dwarfs with large
radii, because the amplitude of the effect depends on the transiting object's
mass and orbital distance. In many binary systems, where a candidate planetary
transit is actually due to the partial eclipse of two normal stars, the
presence of flux variations due to the gravity darkening effect will show the
true nature of these systems. We show that many of the recent OGLE-III
photometric transit candidates exhibit the presence of significant variations
in their light curves and are likely to be due to stellar secondaries. We find
that the light curves of white dwarf transits will generally not mimic those of
small planets because of significant gravitationally induced flux variations.
We discuss the relative merits of methods used to detect transit candidates
which are due to stellar blends rather than planets. We outline how photometric
observations taken in two bands can be used to detect the presence of stellar
blends.Comment: ApJ, 11 pages, 2 figures, 1 table, replaced with accepted versio
Caracterização do sistema de produção de ovinos Santa Inês no Estado de Sergipe.
Com o presente trabalho objetivou-se caracterizar a produção ovina da raça Santa Inês no Estado de Sergipe, referência nacional pela qualidade genética. Através de 54 entrevistas semi-estruturadas e visitas às propriedades, obteve-se o perfil dos criadouros com relação ao manejo sanitário, nutricional e reprodutivo, bem como, finalidade e destino da criação. No geral, as propriedades apresentaram rebanhos de tamanho bastante variável, sendo o sistema semi-intensivo o mais utilizado. Em sua maioria, as criações tinham acompanhamento técnico regular e destinavam-se ao abate ou exploração genética. Criações com assistência veterinária associada a práticas adequadas de manejo mostraram maior produtividade. A carne ovina apresenta crescente demanda de mercado, porém a reduzida quantidade de abatedouros e frigoríficos no Estado parece contribuir como fator determinante para a escoação da produção para feiras livres sem fiscalização sanitária
Black string bounce to traversable wormhole
In this work, a regular black string solution will be presented from the
method used by Simpson-Visser to regularize the Schwarzschild solution. As in
the Simpson-Visser work, in this new black string solution, it is possible to
represent both a regular black hole and a wormhole just by changing the value
of a parameter "" used in its metric. Tensors and curvature invariants were
analyzed to verify the regularity of the solution, as well as the energy
conditions of the system. It was found that the null energy condition will
always be violated for the entire space. The analysis of the thermodynamic
properties of the regular black string was also carried out, in which the
modifications generated about the original solution of the black string, were
evaluated, specifically, the Hawking temperature, entropy, its thermal
capacity, and the Helmholtz free energy. Finally, we investigate the possible
stable or unstable circular orbits for photons and massive particles. The
results were compared with those of the non-regular black string, seeking to
make a parallel with the Simpson-Visser work.Comment: 8 pages, 6 figure
Retenção de placenta em vacas Canchim.
Foi estudada a ocorrência da retenção de placenta no rebanho Canchim.1988Resumo
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