ANOTHER QUADRATURE RULE OF HIGHEST ALGEBRAIC DEGREE OF PRECISION

We consider certain quadrature rules of highest algebraic degree of precision that involve strong Stieltjes distributions (i.e., strong distributions on the positive real axis). The behavior of the parameters of these quadrature rules, when the distributions are strong c-inversive Stieltjes distributions, is given. A quadrature rule whose parameters have explicit expressions for their determination is presented. An application of this quadrature rule for the evaluation of a certain type of integrals is also given.

Use of ideal protein concept for precision formulation of amino acid levels in fish-meal-free diets for juvenile Nile tilapia (Oreochromis niloticus L.)

This study was undertaken in a closed system with Nile tilapia (Oreochromis niloticus) to examine the effects of total replacement of fish meal (FM) by soybean meal. Nile tilapia fingerlings with an average weight of 5.34+/-0.08 g were hand-fed one of the five isoenergetic (approximate to13.5 MJ digestible energy kg(-1)) and isoproteic (approximate to31% of digestible protein) experimental diets to satiation, six times a day during 85 days in eight replicate fibreglass tanks (six fish per tank). The control diet containing FM was substituted by soybean meal, with and without essential amino acids (lysine, methionine and threonine) or dicalcium phosphate supplementation. The supplemental amino acids were added at levels to simulate the reference amino acid profile of Nile tilapia carcass protein, based on the ideal protein concept. The results showed that soybean meal diet supplemented only with dicalcium phosphate was inferior to the control diet with FM and soybean meal diets supplemented with dicalcium phosphate and essential amino acids. Multiple essential amino acids and dicalcium phosphate incorporation in soybean meal diets was associated with performance, whole-body composition and carcass yield equal to that of the fish fed with the control diet containing FM. These data suggest that a diet with all plant protein source, supplemented with essential amino acids, based on tissue amino acid profile, can totally replace FM in a diet for Nile tilapia, without adverse effects on the growth performance, carcass yield and composition.

Differential gene expression by Paracoccidioides brasiliensis in host interaction conditions: Representational difference analysis identifies candidate genes associated with fungal pathogenesis

Paracoccidioides brasiliensis causes infection by the host inhalation of airborne propagules of the mycelia phase of the fungus. These particles reach the lungs, and disseminate to virtually all organs. Here we describe the identification of differentially expressed genes in studies of host-fungus interaction. We analyzed two cDNA populations of P. brasiliensis, one obtained from infected animals and the other an admixture of fungus and human blood thus mimicking the hematologic events of the fungal dissemination. Our analysis identified transcripts differentially expressed. Genes related to iron acquisition, melanin synthesis and cell defense were specially upregulated in the mouse model of infection. The upregulated transcripts of yeast cells during incubation with human blood were those predominantly related to cell wall remodeling/synthesis. The expression pattern of genes was independently confirmed in host conditions, revealing their potential role in the infection process. This work can facilitate functional studies of novel regulated genes that may be important for the survival and growth strategies of P. brasiliensis in humans. (c) 2006 Elsevier Masson SAS. All rights reserved.

Does 75% of the difference between VO2 at lactate threshold and VO2max lie at the severe-intensity domain in well-trained cyclists?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

A device to improve the Schleger and Turner method for sweating rate measurements

The objective of this study was to test a device developed to improve the functionality, accuracy and precision of the original technique for sweating rate measurements proposed by Schleger and Turner [Schleger AV, Turner HG (1965) Aust J Agric Res 16:92-106]. A device was built for this purpose and tested against the original Schleger and Turner technique. Testing was performed by measuring sweating rates in an experiment involving six Mertolenga heifers subjected to four different thermal levels in a climatic chamber. The device exhibited no functional problems and the results obtained with its use were more consistent than with the Schleger and Turner technique. There was no difference in the reproducibility of the two techniques (same accuracy), but measurements performed with the new device had lower repeatability, corresponding to lower variability and, consequently, to higher precision. When utilizing this device, there is no need for physical contact between the operator and the animal to maintain the filter paper discs in position. This has important advantages: the animals stay quieter, and several animals can be evaluated simultaneously. This is a major advantage because it allows more measurements to be taken in a given period of time, increasing the precision of the observations and diminishing the error associated with temporal hiatus (e.g., the solar angle during field studies). The new device has higher functional versatility when taking measurements in large-scale studies (many animals) under field conditions. The results obtained in this study suggest that the technique using the device presented here could represent an advantageous alternative to the original technique described by Schleger and Turner.

Difference equations with delays depending on time

For linear difference equations with coefficients and delays varying in time, sufficient conditions are given, in the scalar case, the zero solution to be stable. © 1990 Sociedade Brasileira de Matemática.

Constraints on free parameters of the simplest bilepton gauge model from the neutral kaon system mass difference

We consider the contributions of the exotic quarks and gauge bosons to the mass difference between the short- and the long-lived neutral kaon states in the SU(3)C×SU(3)L×U(1)N model. The lower bound MZ′∼14 TeV is obtained for the extra neutral gauge boson Z′0. Ranges for values of one of the exotic quark masses and quark mixing parameters are also presented.

The effect of changing the mode of ventilation on the arterial-to-end-tidal CO2 difference and physiological dead space in laterally and dorsally recumbent horses during halothane anesthesia

Objective - To evaluate the effect of changing the mode of ventilation from spontaneous to controlled on the arterial-to-end-tidal CO2 difference [P(a-ET)CO2] and physiological dead space (VD(phys)/VT) in laterally and dorsally recumbent halothane-anesthetized horses. Study Design - Prospective, experimental, nonrandomized trial. Animals - Seven mixed breed adult horses (1 male and 6 female) weighing 320 ± 11 kg. Methods - Horses were anesthetized in 2 positions - right lateral and dorsal recumbency - with a minimum interval of 1 month. Anesthesia was maintained with halothane in oxygen for 180 minutes. Spontaneous ventilation (SV) was used for 90 minutes followed by 90 minutes of controlled ventilation (CV). The same ventilator settings were used for both laterally and dorsally recumbent horses. Arterial blood gas analysis was performed every 30 minutes during anesthesia. End-tidal CO2 (PETCO2) was measured continuously. P(a-ET)CO2 and VD(phys)/VT were calculated. Statistical analysis included analysis of variance for repeated measures over time, followed by Student-Newman-Keuls test. Comparison between groups was performed using a paired t test; P < .05 was considered significant. Results - P(a-ET)CO2 and VD(phys)/VT increased during SV, whereas CV reduced these variables. The variables did not change significantly throughout mechanical ventilation in either group. Dorsally recumbent horses showed greater P(a-ET)CO2 and VD(phys)/VT values throughout. PaCO2 was greater during CV in dorsally positioned horses. Conclusions and Clinical Relevance - Changing the mode of ventilation from spontaneous to controlled was effective in reducing P(a-ET)CO2 and physiological dead space in both laterally and dorsally recumbent halothane-anesthetized horses. Dorsal recumbency resulted in greater impairment of effective ventilation. Capnometry has a limited value for accurate estimation of PaCO, in anesthetized horses, although it may be used to evaluate pulmonary function when paired with arterial blood gas analysis. © Copyright 2000 by The American College of Veterinary Surgeons.

Precision measurements of the ∧c + and D0 lifetimes

A measurement technique of charm baryons lifetimes from hadro-production data was presented. The measurement verified the lifetime analysis procedure in a sample with higher statistical precision. Other effects studied include mass reflections; effects of the presence of a second charm particle; and mismeasurement of charm decays. Monte carlo simulations were used for the detailed study of systematic effects using the charm data.

Métodos de coleta de fezes e determinação dos coeficientes de digestibilidade da fração protéica e da energia de alimentos para o pacu, Piaractus mesopotamicus (Holmberg, 1887)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Precision of yule-walker methods for the arma spectral model

In this work a new method is proposed of separated estimation for the ARMA spectral model based on the modified Yule-Walker equations and on the least squares method. The proposal of the new method consists of performing an AR filtering in the random process generated obtaining a new random estimate, which will reestimate the ARMA model parameters, given a better spectrum estimate. Some numerical examples will be presented in order to ilustrate the performance of the method proposed, which is evaluated by the relative error and the average variation coefficient.

Incidência de malformações congênitas em crianças concebidas através de injeção intracitoplasmática de espermatozóides

Purpose: to evaluate the incidence and types of major congenital malformations (MCM) in liveborn children conceived by intracytoplasmic sperm injection (ICSI). Methods: a total of 680 liveborn children resulted from 511 couples submitted to ICSI from January, 1999 to December, 2002. Data collection of the children was performed through standardized questionnaire and clinical examination. Of the 511 couples, 366 had been contacted for a sampling of 371 gestations. Of the 680 liveborn, 520 had been evaluated, 250 of them (48.1%) through questionnaire and 270 (51.9%) through questionnaire and physical examination. Two hundred and fifty children were from singleton pregnancies and 270 from multiple pregnancies. Malformations were classified according to the 10th revision of the International Statistical Classification of Diseases and Related Health. Only MCM were analyzed in this study. The incidence of MCM was compared with that of the general population obtained by the Latin American Collaborative Study of Congenital Malformations. The statistical analysis was performed by the χ 2 test (level of significance p<0.05). Results: of the 520 children, 15 presented MCM, resulting in an incidence of 2.9%. There was no difference in relation to the control group (p>0.05), which showed 2.6% incidence of MCM. The most frequent malformations were of cardiac origin (four isolated and two associated), corresponding to 40% of the total. The other types of MCM were: renal (three), neural tube (two), skull (one), cleft lip (one), genital (one), Down syndrome (associated with cardiac malformations) (two), and musculoskeletal (one). Six MCM occurred in children from singleton pregnancies and nine in children from multiple pregnancies. Conclusion: the liveborn children conceived by ICSI presented incidence of major congenital malformations (2.9%) near to the expected for the general population (2.6%). However, to establish the risks of MCM with precision it is necessary to continue the evaluation of the children conceived by ICSI.

GPS ambiguity resolution and validation under multipath effects: Improvements using wavelets

Integer carrier phase ambiguity resolution is the key to rapid and high-precision global navigation satellite system (GNSS) positioning and navigation. As important as the integer ambiguity estimation, it is the validation of the solution, because, even when one uses an optimal, or close to optimal, integer ambiguity estimator, unacceptable integer solution can still be obtained. This can happen, for example, when the data are degraded by multipath effects, which affect the real-valued float ambiguity solution, conducting to an incorrect integer (fixed) ambiguity solution. Thus, it is important to use a statistic test that has a correct theoretical and probabilistic base, which has became possible by using the Ratio Test Integer Aperture (RTIA) estimator. The properties and underlying concept of this statistic test are shortly described. An experiment was performed using data with and without multipath. Reflector objects were placed surrounding the receiver antenna aiming to cause multipath. A method based on multiresolution analysis by wavelet transform is used to reduce the multipath of the GPS double difference (DDs) observations. So, the objective of this paper is to compare the ambiguity resolution and validation using data from these two situations: data with multipath and with multipath reduced by wavelets. Additionally, the accuracy of the estimated coordinates is also assessed by comparing with the ground truth coordinates, which were estimated using data without multipath effects. The success and fail probabilities of the RTIA were, in general, coherent and showed the efficiency and the reliability of this statistic test. After multipath mitigation, ambiguity resolution becomes more reliable and the coordinates more precise. © Springer-Verlag Berlin Heidelberg 2007.

Spectral analysis and low-frequency multipath mitigation for kinematic applications

Low-frequency multipath is still one of the major challenges for high precision GPS relative positioning. In kinematic applications, mainly, due to geometry changes, the low-frequency multipath is difficult to be removed or modeled. Spectral analysis has a powerful technique to analyze this kind of non-stationary signals: the wavelet transform. However, some processes and specific ways of processing are necessary to work together in order to detect and efficiently mitigate low-frequency multipath. In this paper, these processes are discussed. Some experiments were carried out in a kinematic mode with a controlled and known vehicle movement. The data were collected in the presence of a reflector surface placed close to the vehicle to cause, mainly, low-frequency multipath. From theanalyses realized, the results in terms of double difference residuals and statistical tests showed that the proposed methodology is very efficient to detect and mitigate low-frequency multipath effects. © 2008 IEEE.