4,040 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
A method to simulate inhomogeneously irradiated objects with a superposition of 1D models
In close binary systems the atmosphere of one or both components can be
significantly influenced by irradiation from the companion. Often the
irradiated atmosphere is simulated with a single-temperature approximation for
the entire half-sphere. We present a scheme to take the varying irradiation
angle into account by combining several separate 1D models. This is independent
of the actual code which provides the separate stellar spectra. We calculate
the projected area of zones with given irradiation angle and use this
geometrical factor to scale separate 1D models. As an example we calculate two
different irradiation scenarios with the PHOENIX code. The scheme to calculate
the projected area is applicable independent of the physical mechanism that
forms these zones. In the case of irradiation by a primary with T=125000 K, the
secondary forms ions at different ionisation states for different irradiation
angles. No single irradiation angle exists which provides an accurate
description of the spectrum. We show a similar simulation for weaker
irradiation, where the profile of the H line depends on the irradiation
angle.Comment: published in A&
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
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A Hidden Complication of Pigtail Catheter Insertion
Pigtail catheters have emerged as an effective and less morbid alternative to traditional chest tubes for evacuation of pleural air. Rare complications in the literature have been reported. We report a case of a 92-year-old male who presented with dyspnea and shock, noted to have a pneumothorax requiring tube thoracostomy. Computed tomography demonstrated pigtail within the lung parenchyma. We discuss the implications of this occurrence
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