5,405 research outputs found
Controle do ácaro-da-necrose-do-coqueiro Aceria guerreronis (Acari: Eriophyidae).
O óleo de algodão bruto vem sendo indicado no controle alternativo do ácaro-da-necrose, no entanto há uma carência de estudos que demonstrema eficiência relativa desse produto no controle da praga bem como de sua seletividade a ácaros predadores. O objetivo do trabalho foi avaliar a eficiência do óleo de algodão bruto em comparação com agrotóxicos registrados para o controle do ácaro-da-necrose bem como sua seletividade ao ácaro predador Typhlodromus ornatus (Acari: Phytoseiidae), comumente encontrado em plantios de coqueiro. Avaliações quinzenais das populações do ácaro-da-necrose demonstraram que Fenpiroximato, Abamectina e o óleo de algodão controlaram eficientemente a praga em condições de campo. Adicionalmente, experimentos de laboratório indicaram que além da toxicidade, esses produtos repelem o ácaro-da-necrose e o ácaro predador T. ornatus.
Invasion Percolation Between two Sites
We investigate the process of invasion percolation between two sites
(injection and extraction sites) separated by a distance r in two-dimensional
lattices of size L. Our results for the non-trapping invasion percolation model
indicate that the statistics of the mass of invaded clusters is significantly
dependent on the local occupation probability (pressure) Pe at the extraction
site. For Pe=0, we show that the mass distribution of invaded clusters P(M)
follows a power-law P(M) ~ M^{-\alpha} for intermediate values of the mass M,
with an exponent \alpha=1.39. When the local pressure is set to Pe=Pc, where Pc
corresponds to the site percolation threshold of the lattice topology, the
distribution P(M) still displays a scaling region, but with an exponent
\alpha=1.02. This last behavior is consistent with previous results for the
cluster statistics in standard percolation. In spite of these discrepancies,
the results of our simulations indicate that the fractal dimension of the
invaded cluster does not depends significantly on the local pressure Pe and it
is consistent with the fractal dimension values reported for standard invasion
percolation. Finally, we perform extensive numerical simulations to determine
the effect of the lattice borders on the statistics of the invaded clusters and
also to characterize the self-organized critical behavior of the invasion
percolation process.Comment: 7 pages, 11 figures, submited for PR
Interface growth in two dimensions: A Loewner-equation approach
The problem of Laplacian growth in two dimensions is considered within the
Loewner-equation framework. Initially the problem of fingered growth recently
discussed by Gubiec and Szymczak [T. Gubiec and P. Szymczak, Phys. Rev. E 77,
041602 (2008)] is revisited and a new exact solution for a three-finger
configuration is reported. Then a general class of growth models for an
interface growing in the upper-half plane is introduced and the corresponding
Loewner equation for the problem is derived. Several examples are given
including interfaces with one or more tips as well as multiple growing
interfaces. A generalization of our interface growth model in terms of
``Loewner domains,'' where the growth rule is specified by a time evolving
measure, is briefly discussed.Comment: To appear in Physical Review
SMART sensor network: with Bluetooth low energy and CAN-BUS
This paper proposes a system to monitor, through the internet, the data of a logistics distribution truck. For this, it was implemented a reliable and flexible wireless sensor network with low energy consumption. The technology used for the radio system was Bluetooth Low Energy (BLE). Each node in the network contains one type of sensor. The sensors information together with GPS and On-Board Diagnostics (OBD) data collected by the central unit, and later transmitted to the cloud by GSM or Wi-Fi.info:eu-repo/semantics/acceptedVersio
Comparative study of osteoarthritis induced by monoiodoacetate and papain in rabbit temporomandibular joints: macroscopic and microscopic analysis
Background: Osteoarthritis (OA) is a chronic, progressive, degenerative pathology. Inducing OA in an animal model is useful for studying the pathology and testing the effectiveness of new treatments. The object of the present study was to determine the macroscopic and microscopic changes occurring in rabbit temporomandibular joints (TMJ) at 15, 30 and 45 days after induction of OA by monoiodoacetate (MIA) and papain.
Materials and methods: Twenty two male rabbits were used in the experiment, divided into three groups: a control group (n = 4) and two experimental groups, MIA (n = 9) and papain (n = 9). The progress of the disease was analysed at 15, 30 and 45 days after induction of OA. Morphological and histological analyses were carried out of the joint disc and the mandibular condyle.
Results: The most evident changes were expressed in the condyle and disc of joints with OA induced by MIA. The condyles presented deformation, fissures and loss of joint surface, the chondrocytes lost their morphology and organisation. In more advanced stages there was loss of the mid zone of the joint disc.
Conclusions: The effects of papain were associated with condyle deformation, disorientation of the chondrocytes in the middle layer, and proliferation in deep zones; there was also an increase in the extracellular matrix. Both inductors generated changes in the TMJ and its joint surfaces; MIA was more effective and coincided more closely with the classic signs of the evolution of OA
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