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Goias, Brazil

De Freitas Bueno R.C.O.,University of Rio Verde | Parra J.R.P.,University of Sao Paulo | De Freitas Bueno A.,Embrapa Soja
Bulletin of Entomological Research | Year: 2012

In order to succeed in biological control programs, not only is it crucial to understand the number of natural enemies to be released but also on how many sites per area this releasing must be performed. These variables might differ deeply among egg parasitoid species and crops worked. Therefore, these trials were carried out to evaluate the parasitism (%) in eggs of Anticarsia gemmatalis and Pseudoplusia includens after the release of different densities of the egg parasitoid Trichogramma pretiosum. Field dispersal was also studied, in order to determine appropriate recommendations for the release of this parasitoid in soybean fields. The regression analysis between parasitism (%) and densities of the parasitoid indicated a quadratic effect for both A. gemmatalis and P. includens. The maximum parasitism within 24 h after the release was reached with densities of 25.6 and 51.2 parasitoids per host egg, respectively, for the two pests. Parasitism of T. pretiosum in eggs of P. includens decreased linearly as the distance of the pest eggs from the parasitoid release sites increased. For P. includens, the mean radius of T. pretiosum action and the area of parasitoid dispersal in the soybean crop were 8.01 m and 85.18 m 2, respectively. We conclude that for a successful biological control program of lepidopteran pests using T. pretiosum in soybean fields, a density of 25.6 parasitoids per host egg, divided into 117 sites per hectare, should be used. © Copyright Cambridge University Press 2011.

De Freitas Bueno R.C.O.,University of Rio Verde | De Freitas Bueno A.,Embrapa Soybean | Moscardi F.,State University Londrina | Postali Parra J.R.,University of Sao Paulo | Hoffmann-Campo C.B.,Embrapa Soybean
Pest Management Science | Year: 2011

BACKGROUND: Defoliation by Anticarsia gemmatalis (Hübner), Pseudoplusia includens (Walker), Spodoptera eridania (Cramer), S. cosmioides (Walker) and S. frugiperda (JE Smith) (Lepidoptera: Noctuidae) was evaluated in four soybean genotypes. A multiple-species economic threshold (ET), based upon the species' feeding capacity, is proposed with the aim of improving growers' management decisions on when to initiate control measures for the species complex.RESULTS: Consumption by A. gemmatalis, S. cosmioides or S. eridania on different genotypes was similar. The highest consumption of P. includens was 92.7 cm 2 on Codetec 219RR; that of S. frugiperda was 118 cm 2 on Codetec 219RR and 115.1 cm 2 on MSoy 8787RR. The insect injury equivalent for S. cosmoides, calculated on the basis of insect consumption, was double the standard consumption by A. gemmatalis, and statistically different from the other species tested, which were similar to each other.CONCLUSIONS: As S. cosmioides always defoliated nearly twice the leaf area of the other species, the injury equivalent would be 2 for this lepidopteran species and 1 for the other species. The recommended multiple-species ET to trigger the beginning of insect control would then be 20 insect equivalents per linear metre. © 2010 Society of Chemical Industry Copyright © 2010 Society of Chemical Industry.

Oliveira L.R.,University of Rio Verde | Castilho-Fernandes A.,University of Sao Paulo | Oliveira-Costa J.P.,University of Sao Paulo | Soares F.A.,A.C. Camargo Cancer Hospital | And 2 more authors.
Head and Neck | Year: 2014

Background. The purpose of this study was to investigate the expression of CD44 and/or CD133 immunophenotypes and the associated effects of matrix metalloproteinase-9 (MMP-9) in early-stage oral squamous cell carcinomas (SCC) to assess their influence on tumor prognosis.Methods. The following data were derived from 150 patients: age, sex, primary anatomic site, smoking status, alcohol intake, recurrence, metastases, histological classification, treatment, disease-free survival (DFS), and overall survival (OS). Immunohistochemical study of CD44, CD133, and MMP-9 expression was performed on a tissue microarray of 150 paraffin blocks of oral SCCs.Results. The predominant immunophenotype identified to exhibit a significant correlation with MMP-9 was the CD441/CD1331. Multivariate analyses identified a significant correlation of OS with surgical treatment and with CD441/CD1331 immunophenotype.Conclusion. This investigation demonstrated the prognostic importance of CD44/CD133 expression, which can help improve the prognostic value of surgical treatment for oral SCCs when diagnosed in early stages. © 2014 Wiley Periodicals, Inc.

Bercu B.,University of Bordeaux 1 | Vazquez V.,University of Rio Verde
Automatica | Year: 2010

We propose a new concept of strong controllability related to the Schur complement of a suitable limiting matrix. This new notion allows us to extend the previous convergence results associated with multidimensional ARX models in stochastic adaptive tracking. On the one hand, we carry out a sharp analysis of the almost sure convergence for both least squares and weighted least squares algorithms. On the other hand, we also provide a central limit theorem and a law of iterated logarithm for these two algorithms. © 2010 Elsevier Ltd. All rights reserved.

This study aimed to evaluate the effect of time since the adoption of the no-till system, in comparison with a native forest area and a conventional tillage area, using the distribution of soil aggregates in a Distroferric Red Nitosol. Treatments were as follows: native forest (NF), conventional tillage (CT), no-till for one year (NT1), no-till for four years (NT4), notill for five years (NT5), and no-till for 12 years (NT12). Aggregate samples were collected randomly within each treatment at depths of 0-5 and 10-15 cm. After sifting the aggregates in water they were separated into the following aggregate classes > 2 mm; < 2 mm; 2-1 mm, and < 1 mm. The adoption time in the no-till system favored soil aggregation. The mean weighted diameter (MWD) of the soil aggregates and the percentage of aggregates greater than 2 mm increased with adoption time in the no-till system at the 0-5 cm depth. The NF and NT12 treatments had higher MWD values in the 0-5 cm layer. CT had the highest percentage of aggregates smaller than 1 mm.

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