Mean anisotropy of homogeneous Gaussian random fields and anisotropic norms of linear translation-invariant operators on multidimensional integer lattices

Sensitivity of output of a linear operator to its input can be quantified in various ways. In Control Theory, the input is usually interpreted as disturbance and the output is to be minimized in some sense. In stochastic worst-case design settings, the disturbance is considered random with imprecisely known probability distribution. The prior set of probability measures can be chosen so as to quantify how far the disturbance deviates from the white-noise hypothesis of Linear Quadratic Gaussian control. Such deviation can be measured by the minimal Kullback-Leibler informational divergence from the Gaussian distributions with zero mean and scalar covariance matrices. The resulting anisotropy functional is defined for finite power random vectors. Originally, anisotropy was introduced for directionally generic random vectors as the relative entropy of the normalized vector with respect to the uniform distribution on the unit sphere. The associated a-anisotropic norm of a matrix is then its maximum root mean square or average energy gain with respect to finite power or directionally generic inputs whose anisotropy is bounded above by a≥0. We give a systematic comparison of the anisotropy functionals and the associated norms. These are considered for unboundedly growing fragments of homogeneous Gaussian random fields on multidimensional integer lattice to yield mean anisotropy. Correspondingly, the anisotropic norms of finite matrices are extended to bounded linear translation invariant operators over such fields.

Rock fracture mean trace length estimation and confidence interval calculation using maximum likelihood methods

There has been a resurgence of interest in the mean trace length estimator of Pahl for window sampling of traces. The estimator has been dealt with by Mauldon and Zhang and Einstein in recent publications. The estimator is a very useful one in that it is non-parametric. However, despite some discussion regarding the statistical distribution of the estimator, none of the recent works or the original work by Pahl provide a rigorous basis for the determination a confidence interval for the estimator or a confidence region for the estimator and the corresponding estimator of trace spatial intensity in the sampling window. This paper shows, by consideration of a simplified version of the problem but without loss of generality, that the estimator is in fact the maximum likelihood estimator (MLE) and that it can be considered essentially unbiased. As the MLE, it possesses the least variance of all estimators and confidence intervals or regions should therefore be available through application of classical ML theory. It is shown that valid confidence intervals can in fact be determined. The results of the work and the calculations of the confidence intervals are illustrated by example. (C) 2003 Elsevier Science Ltd. All rights reserved.

Optimising high-intensity treadmill training using the running speed at maximal O-2 uptake and the time for which this can be maintained

The aim of this study was to compare the effects of two high-intensity, treadmill interval-training programs on 3000-m and 5000-m running performance. Maximal oxygen uptake ((V) over dot O-2max), the running speed associated with (V) over dot O-2max (nu (V) over dot O-2max), the time for which nu (V) over dot O-2max can be maintained (T-max), running economy (RE), ventilatory threshold (VT) and 3000-m and 5000-m running times were determined in 27 well-trained runners. Subjects were then randomly assigned to three groups; (1) 60% T-max (2) 70% T-max and (3) control. Subjects in the control group continued their normal training and subjects in the two T-max groups undertook a 4-week treadmill interval-training program with the intensity set at nu (V) over dot O-2max and the interval duration at the assigned T-max. These subjects completed two interval-training sessions per week (60% T-max = six intervals/session, 70% T-max group = five intervals/session). Subjects were re-tested on all parameters at the completion of the training program. There was a significant improvement between pre- and post-training values in 3000-m time trial (TT) performance in the 60% T-max group compared to the 70% T,,a, and control groups [mean (SE); 60% T-max = 17.6 (3.5) s, 70% T-max = 6.3 (4.2) s, control = 0.5 (7.7) s]. There was no significant effect of the training program on 5000-m TT performance [60% T-max = 25.8 (13.8) s, 70% T-max = 3.7 (11.6) s, control = 9.9 (13.1) s]. Although there were no significant improvements in (V) over dot O-2max, nu (V) over dot (2max) and RE between groups, changes in (V) over dot O-2max and RE were significantly correlated with the improvement in the 3000-m TT. Furthermore, VT and T-max were significantly higher in the 60% Tmax group post-compared to pre-training. In conclusion, 3000-m running performance can be significantly improved in a group of well-trained runners, using a 4-week treadmill interval training program at nu (V) over dot O-2max with interval durations of 60% T-max.

EMA analysis of tongue function in children with dysarthria following traumatic brain injury

Primary objective : To investigate the speed and accuracy of tongue movements exhibited by a sample of children with dysarthria following severe traumatic brain injury (TBI) during speech using electromagnetic articulography (EMA). Methods and procedures : Four children, aged between 12.75-17.17 years with dysarthria following TBI, were assessed using the AG-100 electromagnetic articulography system (Carstens Medizinelektronik). The movement trajectories of receiver coils affixed to each child's tongue were examined during consonant productions, together with a range of quantitative kinematic parameters. The children's results were individually compared against the mean values obtained by a group of eight control children (mean age of 14.67 years, SD 1.60). Main outcomes and results : All four TBI children were perceived to exhibit reduced rates of speech and increased word durations. Objective EMA analysis revealed that two of the TBI children exhibited significantly longer consonant durations compared to the control group, resulting from different underlying mechanisms relating to speed generation capabilities and distances travelled. The other two TBI children did not exhibit increased initial consonant movement durations, suggesting that the vowels and/or final consonants may have been contributing to the increased word durations. Conclusions and clinical implications : The finding of different underlying articulatory kinematic profiles has important implications for the treatment of speech rate disturbances in children with dysarthria following TBI.

Transition to raloxifene with and without low-dose estrogen therapy in postmenopausal women: effects on serum lipids and fibrinogen - a pilot study

Objective To compare the effects of transferring from low-dose transdermal estrogen to raloxifene (RLX), with a phase of alternate-day RLX therapy with or without low-dose transdermal estrogen, on serum lipids and fibrinogen in postmenopausal women previously administered estrogen plus progestogen therapy. Methods Sixty postmenopausal women (mean age 55 years) were randomized to one of two treatment groups: RLX + low-dose transdermal estrogen (RLX + E) or RLX + placebo. The study consisted of four 8-week phases: phase I (all subjects low-dose transdermal estrogen 25 mug/day), phase II (double-blind RLX 60 mg every 2nd day in combination with either low-dose transdermal estrogen or placebo), phase III (all subjects RLX 60 mg every 2nd day + placebo) and phase IV (all subjects RLX 60 mg/day + placebo). Results No significant differences existed between groups for baseline measurements prior to phase I. In phase I, for all subjects combined, total cholesterol and low-density lipoprotem cholesterol both showed a significant increase (median increase of 0.2 mmol/l, p = 0.008 and 0.4 mmol/l, p < 0.001, respectively), while triglycerides decreased significantly (median decrease of 0.2 mmol/l, p < 0.001). For the primary analysis (phase II to phase IV), the mean change from baseline observations showed no significant differences between the therapy groups for serum lipids, fibrinogen, vital signs or weight. In the comparison phase (phase II), changes in serum lipids, fibrinogen, vital signs and weight were not significantly different between groups. Conclusion Gradual conversion to RLX from low-dose transdermal estrogen, with a phase of alternate-day RLX therapy with or without low-dose transdermal estrogen, does not have any effect on the serum lipid profile or fibrinogen level.

UFES, 60 anos

Organizador, Universidade Federal do Espírito Santo.

Modelagem e simulação de um secador intermitente de fluxos contracorrentes para frutos do cafeeiro

Este trabalho foi realizado com o objetivo de desenvolver um modelo computacional para simular a secagem de frutos café em um secador intermitente de fluxos contracorrente, empregando a linguagem de simulação EXTEND™ e o Modelo de Thompson (THOMPSON; PEART; FOSTER, 1968). Para validação do modelo desenvolvido foram utilizados dados experimentais obtidos por Silva (1991), em que foram empregados três níveis de temperatura do ar de secagem de 60, 80 e 100 °C. O modelo desenvolvido foi validado, sendo constatados desvios absolutos de 1,8% b.u e 1,1 kg e erros relativos de 11% e 1,6% na previsão dos parâmetros teor de água final e consumo de lenha, respectivamente. O modelo validado foi empregado na condução de experimentos tipo comparação de cenários. O primeiro experimento refere a alterações do ciclo operacional em que foram alterados os tempos de movimentação e de parada do fluxo da massa de grãos. E o segundo refere à alteração da configuração do secador quanto às alturas das câmaras de secagem e descanso. O ciclo operacional com os tempos de movimentação de um minuto e de parada de dezesseis minutos, para a temperatura do ar de secagem de 100 °C, proporcionou o melhor desempenho, sendo constatado tempo secagem de 12,3 h, consumo de lenha de 109,5 kg, consumo específico de energia de 7660 kJ.kg-1 de água evaporada, e capacidade de secagem de 87,86 kg.h-1. Quanto à configuração do secador, o melhor desempenho ocorreu para altura da câmara de secagem de 2,3 m usando a temperatura do ar de secagem de 100 °C, em que foram simulados tempo de secagem de 12,0 h, consumo de lenha de 106,5 kg, consumo específico de energia, de 7433 kJ.kg-1 de água evaporada, e capacidade de secagem de 90 kg.h-1. Desse modo, na condução da secagem de frutos de café em um secador intermitente de fluxos contracorrentes é recomendado o ciclo operacional com tempos de movimentação de um minuto e o de parada de dezesseis minutos, e não empregar a câmara de descanso. Essa conclusão está fundamentada em índices de desempenho do secador. Ressalta-se que não foram simulados os impactos nos parâmetros de qualidade.

Indicação inicial de tratamento em 60 pacientes com distúrbios ventilatórios obstrutivos do sono

OBJETIVO: Os autores apresentam um estudo descritivo retrospectivo de 60 pacientes portadores de distúrbios ventilatórios obstrutivos do sono (DVOS), atendidos no Centro Campinas de Otorrinolaringologia e Cirurgia de Cabeça e Pescoço num período de três anos. Todos os pacientes foram examinados segundo protocolo padronizado e as decisões quanto à primeira conduta terapêutica resultaram de discussão conjunta multidisciplinar sistemática. FORMA DE ESTUDO: clínico retrospectivo. MATERIAL E MÉTODO: Os pacientes foram distribuídos em dois grupos segundo a proposta de tratamento não-cirúrgico e cirúrgico. Em seguida, foram estudados quanto à modalidade inicial de tratamentos propostos e os principais achados propedêuticos: índice de distúrbio respiratório (IDR), índice de massa corpórea (IMC), análise cefalométrica e manobra de Müller. Os principais achados propedêuticos foram comparados, isoladamente ou em associações com a modalidade de tratamento proposto. CONCLUSÃO: As principais conclusões mostram que nas roncopatias, a indicação de tratamento não-cirúrgico e cirúrgico se fez na mesma proporção; a indicação de tratamento cirúrgico prevaleceu na Síndrome da Apnéia-Hipopnéia Obstrutiva do Sono (SAHOS), independente de sua modalidade; o IDR, o IMC e a manobra de Müller não tiveram influência na indicação de qualquer modalidade terapêutica; a decisão terapêutica decorreu de estudo propedêutico sistematizado e da atuação multidisciplinar, havendo cada caso sido discutido individualmente.

Drying kinetics of jatropha seeds

Given the necessity of developing jatropha cultivation equipment, this work adjusted different mathematical models to experimental data obtained from the drying of jatropha seeds submitted to different drying conditions and selected the best model to describe the drying process. The experiment was carried out at the Federal Institute of Goiás - Rio Verde Campus. Seeds with initial moisture content of approximately 0.50 (kg water/kg dry matter) were dried in a forced air-ventilated oven, at temperatures of 45, 60, 75, 90 and 105°C to moisture content of 0.10 ± 0.005 (kg water/kg dry matter). The experimental data were adjusted to 11 mathematical models to represent the drying process of agricultural products. The models were compared using the coefficient of determination, chi-square test, relative mean error, estimated mean error and residual distribution. It was found that the increase in the air temperature caused a reduction in the drying time of seeds. The models Midilli and Two Terms were suitable to represent the drying process of Jatropha seeds and between them the use of the Midili model is recommended due to its greater simplicity.

Methods to classify maize cultivars in use efficiency and response to nitrogen

n plant breeding programs that aim to obtain cultivars with nitrogen (N) use efficiency, the focus is on methods of selection and experimental procedures that present low cost, fast response, high repeatability, and can be applied to a large number of cultivars. Thus, the objectives of this study were to classify maize cultivars regarding their use efficiency and response to N in a breeding program, and to validate the methodology with contrasting doses of the nutrient. The experimental design was a randomized block with the treatments arranged in a split-plot scheme with three replicates and five N doses (0, 30, 60, 120 and 200 kg ha-1) in the plots, and six cultivars in subplots. We compared a method examining the efficiency and response (ER) with two contrasting doses of N. After that, the analysis of variance, mean comparison and regression analysis were performed. In conclusion, the method of the use efficiency and response based on two N levels classifies the cultivars in the same way as the regression analysis, and it is appropriate in plant breeding routine. Thus, it is necessary to identify the levels of N required to discriminate maize cultivars in conditions of low and high N availability in plant breeding programs that aim to obtain efficient and responsive cultivars. Moreover, the analysis of the interaction genotype x environment at experiments with contrasting doses is always required, even when the interaction is not significant.

Semi-automatic 3D Segmentation Of Costal Cartilage In CT Data From Pectus Excavatum Patients

One of the current frontiers in the clinical management of Pectus Excavatum (PE) patients is the prediction of the surgical outcome prior to the intervention. This can be done through computerized simulation of the Nuss procedure, which requires an anatomically correct representation of the costal cartilage. To this end, we take advantage of the costal cartilage tubular structure to detect it through multi-scale vesselness filtering. This information is then used in an interactive 2D initialization procedure which uses anatomical maximum intensity projections of 3D vesselness feature images to efficiently initialize the 3D segmentation process. We identify the cartilage tissue centerlines in these projected 2D images using a livewire approach. We finally refine the 3D cartilage surface through region-based sparse field level-sets. We have tested the proposed algorithm in 6 noncontrast CT datasets from PE patients. A good segmentation performance was found against reference manual contouring, with an average Dice coefficient of 0.75±0.04 and an average mean surface distance of 1.69±0.30mm. The proposed method requires roughly 1 minute for the interactive initialization step, which can positively contribute to an extended use of this tool in clinical practice, since current manual delineation of the costal cartilage can take up to an hour.

Condições de saúde bucal em pessoas de 60 anos ou mais no Município de São Paulo (Brasil)

As condições de saúde bucal no grupo populacional com 60 anos ou mais é estudada, na cidade de São Paulo em 1989. Com base em dados referentes à cárie dental, doenças periodontais, necessidade e uso de prótese e prevalência de alterações em tecidos duros e moles, conclui-se que este grupo apresenta um nível muito precário de saúde bucal. Recomenda-se a definição de política e de programas odontológicos específicos para a terceira idade.