1000 resultados para Normal vector
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The paper presents a new theory for modeling flow in anisotropic, viscous rock. This theory has originally been developed for the simulation of large deformation processes including folding and kinking in multi-layered visco-elastic rock. The orientation of slip planes in the context of crystallographic slip is determined by the normal vector, the so-called director of these surfaces. The model is applied to simulate anisotropic natural mantle convection. We compare the evolution of the director and approximately steady states of isotropic and anisotropic convection. The isotropic case has a simple steady state solution, whereas the orthotropic convection model produces a continuously evolving patterning in tile core of the convection cell which makes only a near-steady condition possible, in which the thermal boundary layer appears to be well aligned with the flow and hence as observed in seismic tomomgraphy strong anistropic.
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State of Sao Paulo Research Foundation (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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In dieser Arbeit wurde die paritätsverletzende Asymmetrie in derrnquasielastischen Elektron-Deuteron-Streuung bei Q^2=0.23 (GeV/c)^2 mitrneinem longitudinal polarisierten Elektronstrahl bei einer Energie von 315rnMeV bestimmt. Die Messung erfolgte unter Rückwärtswinkeln. Der Detektor überdeckte einen polaren Streuwinkelbereichrnzwischen 140 und 150 deg. Das Target bestand aus flüssigemrnDeuterium in einer Targetzelle mit einer Länge von 23.4 cm. Dierngemessene paritätsverletzende Asymmetrie beträgt A_{PV}^d = (-20.11 pm 0.87_{stat} pm 1.03_{syst}), wobei der erste Fehler den statistischenrnFehlereitrag und der zweite den systematischen Fehlerbeitrag beschreibt. Ausrnder Kombination dieser Messung mit Messungen der paritätsverletzendenrnAsymmetrie in der elastischen Elektron-Proton-Streuung bei gleichem Q^2rnsowohl bei Vorwärts- als auch bei Rückwärtsmessungen können diernVektor-Strange-Formfaktoren sowie der effektive isovektorielle und isoskalarernVektorstrom des Protons, der die elektroschwachen radiativen Anapolkorrekturenrnenthält, bestimmt werden. Diese Arbeit umfasst ausserdem die Bestimmungrnder Asymmetrien bei einem transversal polarisierten Elektronstrahl sowohl beirneinem Proton- als auch einem Deuterontarget unter Rückwärtswinkeln beirnImpulsüberträgen von Q^2=0.10 (GeV/c)^2, Q^2=0.23 (GeV/c)^2rnund Q^2=0.35 (GeV/c)^2. Die im Experiment beobachteten Asymmetrien werdenrnmit theoretischen Berechnungen verglichen, welche den Imaginärteil der Zweiphoton-Austauschamplitude beinhalten.
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As in Alzheimer-disease (AD) brain, vacuolated muscle fibers of inclusion-body myositis (IBM) contain abnormally accumulated beta-amyloid precursor protein (beta APP), including its beta-amyloid protein epitope, and increased beta APP-751 mRNA. Other similarities between IBM muscle and AD brain phenotypes include paired helical filaments, hyperphosphorylated tau protein, apolipoprotein E, and mitochondrial abnormalities, including decreased cytochrome-c oxidase (COX) activity. The pathogenesis of these abnormalities in IBM muscle and AD brain is not known. We now report that direct transfer of the beta APP gene, using adenovirus vector, into cultured normal human muscle fibers causes structural abnormalities of mitochondria and decreased COX activity. In this adenovirus-mediated beta APP gene transfer, we demonstrated that beta APP overproduction can induce mitochondrial abnormalities. The data suggest that excessive beta APP may be responsible for mitochondrial and COX abnormalities in IBM muscle and perhaps AD brain.
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Purpose: To define a range of normality for the vectorial parameters Ocular Residual Astigmatism (ORA) and topography disparity (TD) and to evaluate their relationship with visual, refractive, anterior and posterior corneal curvature, pachymetric and corneal volume data in normal healthy eyes. Methods: This study comprised a total of 101 consecutive normal healthy eyes of 101 patients ranging in age from 15 to 64 years old. In all cases, a complete corneal analysis was performed using a Scheimpflug photography-based topography system (Pentacam system Oculus Optikgeräte GmbH). Anterior corneal topographic data were imported from the Pentacam system to the iASSORT software (ASSORT Pty. Ltd.), which allowed the calculation of the ocular residual astigmatism (ORA) and topography disparity (TD). Linear regression analysis was used for obtaining a linear expression relating ORA and posterior corneal astigmatism (PCA). Results: Mean magnitude of ORA was 0.79 D (SD: 0.43), with a normality range from 0 to 1.63 D. 90 eyes (89.1%) showed against-the-rule ORA. A weak although statistically significant correlation was found between the magnitudes of posterior corneal astigmatism and ORA (r = 0.34, p < 0.01). Regression analysis showed the presence of a linear relationship between these two variables, although with a very limited predictability (R2: 0.08). Mean magnitude of TD was 0.89 D (SD: 0.50), with a normality range from 0 to 1.87 D. Conclusion: The magnitude of the vector parameters ORA and TD is lower than 1.9 D in the healthy human eye.
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In this paper an alternative approach to the one in Henze (1986) is proposed for deriving the odd moments of the skew-normal distribution considered in Azzalini (1985). The approach is based on a Pascal type triangle, which seems to greatly simplify moments computation. Moreover, it is shown that the likelihood equation for estimating the asymmetry parameter in such model is generated as orthogonal functions to the sample vector. As a consequence, conditions for a unique solution of the likelihood equation are established, which seem to hold in more general setting.
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The application of functional magnetic resonance imaging (fMRI) in neuroscience studies has increased enormously in the last decade. Although primarily used to map brain regions activated by specific stimuli, many studies have shown that fMRI can also be useful in identifying interactions between brain regions (functional and effective connectivity). Despite the widespread use of fMRI as a research tool, clinical applications of brain connectivity as studied by fMRI are not well established. One possible explanation is the lack of normal pattern, and intersubject variability-two variables that are still largely uncharacterized in most patient populations of interest. In the current study, we combine the identification of functional connectivity networks extracted by using Spearman partial correlation with the use of a one-class support vector machine in order construct a normative database. An application of this approach is illustrated using an fMRI dataset of 43 healthy Subjects performing a visual working memory task. In addition, the relationships between the results obtained and behavioral data are explored. Hum Brain Mapp 30:1068-1076, 2009. (C) 2008 Wiley-Liss. Inc.
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Reported are observations on spontaneous occurring morphogenetic juvenilization in laboratory populations of vector species of Chagas disease. Two general effects have been observed: arrested development and uncoordinated development. These are manifested by supernumerary nymphs (6th stage), intermediate nymphal-adult stages, badly deformed adults developed from 5th instar nymphs, uncoordinated development manifested by grotesque forms of adults, supernumerary adults unable to complete metamorphosis and complete supernumerary adults produced by 6th stage nymphs. The reoccurrence of insects with identical grades of juvenilization in the population is an indication that this is a genetic trait that might be inherited. The factors responsible for morphogenetic juvenilization cannot be transmitted through the juvenilized insects because they are sterile, than they were transmitted through normal insects probably as a recessive or a group recessive factors. The spontaneous morphogenetic juvenilization observed in laboratory populations has a striking similarity to juvenilizing effects induced by application of juvenile hormone analogues, described in the literature and also obtained in our laboratory in a study to be published. Thus it is suggested that both; the altered phenotypes occurring in wild populations and their "phenocopies" induced by the application of juvenile hormone analogues are products of gene controlled identical reactions.
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The development of integrated measures which involve sterile mate release to supplement the conventional insecticidal techniques used in controlagainst insects of medical importance, raised the question, whether the vectors of Chagas'disease possess the natural mechanisms by manipulation of which they may be controlled. Results of earlier expenments, that had been published previously, were restricted to fragmentary information that raised various questions, the answer to which became available in the study herein described. Interspecific hybrids were produced from reciprocal crosses between T. pseudomaculata and T. sórdida and from unilateral crosses between female T. pseudomaculata and male. T. infestans. These females mated with males, laid less than the normal complement of eggs, but offspring was relatively abundant. When T. pseudomaculata females were paired with T. brasiliensis males, hybridization was more difficult because few of the females mated and those that did had a strongly reduced fertility. Adults emerged from ali crosses but exhibited sex disproportion, females predominating in all populations but one. The two Rhodnius species tested were also found to cross, but only when female R. prolixus were paired with male R. neglectus. These females laid a relatively high complement o f eggs, had a strongly reduced fertility, but 50% of the fertile eggs developed into vigorous adults, males predominating females. Neither type of hybrid male elicited fertilized eggs from either parental type of female, through their vesicula seminal is were found to be packed with spermatozoa, some normal looking and moving, others underdeveloped and motionless. Although, no artificial insemination was performed, the sperm in itself did not appear to be the prime inducer of sterility. Females paired with these hybrids did mate, sperm was transfered, as evidenced by the discharged spermatophores smeared with sperm, but did notcontain spermatozoa in their spermatecae. The failure of the sperm to migrate to the spermatecae indicate prezygotic pos-copulation incompatibility, thus the hybrid male can't be used to suppress populations. The female hybrids mated with parent males of either species had reduced fertility and ther sons were sterile as were those of their fertile daughters. However, continous backcrossing of the hybrid females and their female progeny to parental males partially restored fertility of the males and increased fertility of females, as scored by egg hatchability. Fertility of hybrid females, measured by the yield of adults capable to reproduce, indicated that the reproductive perfomance decreased when hybrid females and their daughters were backcrossed additional generations to parental males. It is tentatively suggested that hybrid females could be used for suppression if they compete efficiently with wild females.
Advanced megaesophagus (Group III) secondary to vector-borne Chagas disease in a 20-month-old infant
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The authors report the case of a female infant with Group III (or Grade III) megaesophagus secondary to vector-borne Chagas disease, resulting in severe malnutrition that reversed after surgery (Heller technique). The infant was then treated with the antiparasitic drug benznidazole, and the infection was cured, as demonstrated serologically and parasitologically. After follow-up of several years without evidence of disease, with satisfactory weight and height development, the patient had her first child at age 23, in whom serological tests for Chagas disease yielded negative results. Thirty years after the initial examination, the patient's electrocardiogram, echocardiogram, and chest radiography remained normal.
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OBJECTIVE: To assess signal-averaged electrocardiogram (SAECG) for diagnosing incipient left ventricular hypertrophy (LVH). METHODS: A study with 115 individuals was carried out. The individuals were divided as follows: GI - 38 healthy individuals; GII - 47 individuals with mild to moderate hypertension and normal findings on echocardiogram and ECG; and GIII - 30 individuals with hypertension and documented LVH. The magnitude vector of the SAECG was analyzed with the high-pass cutoff frequency of 40 Hz through the bidirectional four-pole Butterworth high-pass digital filter. The mean quadratic root of the total QRS voltage (RMST) and the two-dimensional integral of the QRS area of the spectro-temporal map were analyzed between 0 and 30 Hz for the frequency domain (Int FD), and between 40 and 250 Hz for the time domain (Int TD). The electrocardiographic criterion for LVH was based on the Cornell Product. Left ventricular mass was calculated with the Devereux formula. RESULTS: All parameters analyzed increased from GI to GIII, except for Int FD (GII vs GIII) and RMST log (GII vs GIII). Int TD showed greater accuracy for detecting LVH with an appropriate cutoff > 8 (sensitivity of 55%, specificity of 81%). Positive values (> 8) were found in 56.5% of the G II patients and in 18.4% of the GI patients (p< 0.0005). CONCLUSION: SAECG can be used in the early diagnosis of LVH in hypertensive patients with normal ECG and echocardiogram.
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The manuscript describes a study on the blood cholinesterase (ChE) level in an exposed population at different interval of time after spraying with malathion suspension (SRES) use for kala-azar vector control in an endemic area of Bihar, India. The toxicity of a 5% malathion formulation in the form of a slow release emulsified suspension (SRES) was assessed by measuring serum ChE levels in spraymen and in the exposed population.The study showed a significant decrease in ChE levels in the spraymen (p < 0.01) after one week of spraying and in exposed population one week and one month after of spraying (p < 0.01), but was still within the normal range of ChE concentration, one year after spraying, the ChE concentration in the exposed population was the same as prior to spraying (p > 0.01). On no occasion was the decrease in ChE level alarming. A parallel examination of the clinical status also showed the absence of any over toxicity or any behavioural changes in the exposed population. Hence, it may be concluded that 5% malathion slow release formulation, SRES, is a safe insecticide for use as a vector control measure in endemic areas of kala-azar in Bihar, India so long as good personal protection for spraymen is provided to minimize absorption and it can substitute the presently used traditional DDT spray.
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Introduction: In normal mice, lentiviral vector (LV) shows a great efficiency to infect the RPE cells, but transduces retinal neurons more efficiently during development. Here, we investigated the tropism of LV in the degenerating retina of mice, knowing that the retina structure changes during degeneration. We postulated that the viral transduction would be increased by the alteration of the interphotoreceptor matrix (IPM). We tested two different LV-pseudotypes using the VSVG and the Mokola envelopes. Methods: Subretinal injections were performed in wild-type (C57/Bl6) and rhodopsin knockout (Rho-/-) mice. We injected LV-VSVG-EFS-GFPII into 3.3-4.9 month old mice and LV-VSVG-Rho-GFP into 1-1.4 month old mice to target the photoreceptors (PR). LV-MOK-CMV-GFP was injected into 2.4-3.3 months old mice. We sacrificed the animals one week post injection, used immunohistochemistry to identify the transduced cells, and investigated the OLM integrity. Results: Using LV-VSVG-EFS-GFPII into 3.3-4.9 months mice, we observed significant retinal and RPE transduction in Rho-/- mice. However, the retinas showed transduction mainly at the injection's site. We mostly observed GFP+ cells having a Müller cell morphology. Using LV-MOK-CMV-GFP into 2.4-3.3 months mice, we evidenced the same pattern of viral infection, but with more Müller cells targeted by the virus. Using LV-VSVG-Rho-GFP into 1-1.4 month old mice, we don't note any difference between Rho-/- and wild-type mice for transduced cells. The IPM stained with ZO1 appears irregular into the 4.9 months old Rho-/- mice; for the youngest mice (Rho-/- and C57/Bl6), there is no modification of the IPM. Conclusion: The degeneration improves retinal cells transduction due to the alteration of the IPM in old Rho-/- mice. Müller cells seem (by morphological evidences) to be the principal cells expressing the transgene. The LV with Mokola envelope can transduce Müller cells in a degenerating retina with an intact IPM. In 1 month old mice, the degeneration doesn't enhance the transduction in rod PR probably because the IPM is not yet altered. The possibility to target photoreceptors at a later stage of the degeneration is under investigation.
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In this paper, we give a new construction of resonant normal forms with a small remainder for near-integrable Hamiltonians at a quasi-periodic frequency. The construction is based on the special case of a periodic frequency, a Diophantine result concerning the approximation of a vector by independent periodic vectors and a technique of composition of periodic averaging. It enables us to deal with non-analytic Hamiltonians, and in this first part we will focus on Gevrey Hamiltonians and derive normal forms with an exponentially small remainder. This extends a result which was known for analytic Hamiltonians, and only in the periodic case for Gevrey Hamiltonians. As applications, we obtain an exponentially large upper bound on the stability time for the evolution of the action variables and an exponentially small upper bound on the splitting of invariant manifolds for hyperbolic tori, generalizing corresponding results for analytic Hamiltonians.