997 resultados para Measurement Variability


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We report measurements of single- and double-spin asymmetries for W^{±} and Z/γ^{*} boson production in longitudinally polarized p+p collisions at sqrt[s]=510  GeV by the STAR experiment at RHIC. The asymmetries for W^{±} were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the W mass. The results are compared to theoretical predictions, constrained by polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range 0.05

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Passiflora species are distributed throughout Latin America, and Brazil and Colombia serve as the centers of diversity for this genus. We performed cross-species amplification to evaluate 109 microsatellite loci in 14 Passiflora species and estimated the diversity and genetic structure of Passiflora cincinnata, Passiflora setaceae and Passiflora edulis. A total of 127 accessions, including 85 accessions of P. edulis, a commercial species, and 42 accessions of 13 wild species, were examined. The cross-species amplification was effective for obtaining microsatellite loci (average cross-amplification of 70%). The average number of alleles per locus (five) was relatively low, and the average diversity ranged from 0.52 in P. cincinnata to 0.32 in P. setacea. The Bayesian analyses indicated that the P. cincinnata and P. setacea accessions were distributed into two groups, and the P. edulis accessions were distributed into five groups. Private alleles were identified, and suggestions for core collections are presented. Further collections are necessary, and the information generated may be useful for breeding and conservation.

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American tegumentary leishmaniasis (ATL) is a disease transmitted to humans by the female sandflies of the genus Lutzomyia. Several factors are involved in the disease transmission cycle. In this work only rainfall and deforestation were considered to assess the variability in the incidence of ATL. In order to reach this goal, monthly recorded data of the incidence of ATL in Orán, Salta, Argentina, were used, in the period 1985-2007. The square root of the relative incidence of ATL and the corresponding variance were formulated as time series, and these data were smoothed by moving averages of 12 and 24 months, respectively. The same procedure was applied to the rainfall data. Typical months, which are April, August, and December, were found and allowed us to describe the dynamical behavior of ATL outbreaks. These results were tested at 95% confidence level. We concluded that the variability of rainfall would not be enough to justify the epidemic outbreaks of ATL in the period 1997-2000, but it consistently explains the situation observed in the years 2002 and 2004. Deforestation activities occurred in this region could explain epidemic peaks observed in both years and also during the entire time of observation except in 2005-2007.

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One of the most important properties of quantum dots (QDs) is their size. Their size will determine optical properties and in a colloidal medium their range of interaction. The most common techniques used to measure QD size are transmission electron microscopy (TEM) and X-ray diffraction. However, these techniques demand the sample to be dried and under a vacuum. This way any hydrodynamic information is excluded and the preparation process may alter even the size of the QDs. Fluorescence correlation spectroscopy (FCS) is an optical technique with single molecule sensitivity capable of extracting the hydrodynamic radius (HR) of the QDs. The main drawback of FCS is the blinking phenomenon that alters the correlation function implicating in a QD apparent size smaller than it really is. In this work, we developed a method to exclude blinking of the FCS and measured the HR of colloidal QDs. We compared our results with TEM images, and the HR obtained by FCS is higher than the radius measured by TEM. We attribute this difference to the cap layer of the QD that cannot be seen in the TEM images.

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Measurement instruments are an integral part of clinical practice, health evaluation and research. These instruments are only useful and able to present scientifically robust results when they are developed properly and have appropriate psychometric properties. Despite the significant increase of rating scales, the literature suggests that many of them have not been adequately developed and validated. The scope of this study was to conduct a narrative review on the process of developing new measurement instruments and to present some tools which can be used in some stages of the development process. The steps described were: I-The establishment of a conceptual framework, and the definition of the objectives of the instrument and the population involved; II-Development of the items and of the response scales; III-Selection and organization of the items and structuring of the instrument; IV-Content validity, V-Pre-test. This study also included a brief discussion on the evaluation of the psychometric properties due to their importance for the instruments to be accepted and acknowledged in both scientific and clinical environments.

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X-linked adrenoleukodystrophy (X-ALD) is an inherited disease with clinical heterogeneity varying from presymptomatic individuals to rapidly progressive cerebral ALD forms. This disease is characterized by increased concentration of very long chain fatty acids (VLCFAs) in plasma and in adrenal, testicular and nervous tissues. Affected individuals can be classified in different clinical settings, according to phenotypic expression and age at onset of initial symptoms. Molecular defects in X-ALD individuals usually result from ABCD1 gene mutations. In the present report we describe clinical data and the ABCD1 gene study in two boys affected with the childhood cerebral form that presented with different symptomatic manifestations at diagnosis. In addition, their maternal grandfather had been diagnosed with Addison's disease indicating phenotypic variation for X-ALD within this family. The mutation p.Trp132Ter was identified in both male patients; additionally, three females, out of eleven family members, were found to be heterozygous after screening for this mutation. In the present report, the molecular analysis was especially important since one of the heterozygous females was in first stages of pregnancy. Therefore, depending on the fetus outcome, if male and p.Trp132Ter carrier, storage of the umbilical cord blood should be recommended as hematopoietic stem cell transplantation could be considered as an option for treatment in the future.

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas . Faculdade de Educação Física

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Universidade Estadual de Campinas. Faculdade de Educação Física

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Two experiments evaluated an operant procedure for establishing stimulus control using auditory and electrical stimuli as a baseline for measuring the electrical current threshold of electrodes implanted in the cochlea. Twenty-one prelingually deaf children, users of cochlear implants, learned a Go/No Go auditory discrimination task (i.e., pressing a button in the presence of the stimulus but not in its absence). When the simple discrimination baseline became stable, the electrical current was manipulated in descending and ascending series according to an adapted staircase method. Thresholds were determined for three electrodes, one in each location in the cochlea (basal, medial, and apical). Stimulus control was maintained within a certain range of decreasing electrical current but was eventually disrupted. Increasing the current recovered stimulus control, thus allowing the determination of a range of electrical currents that could be defined as the threshold. The present study demonstrated the feasibility of the operant procedure combined with a psychophysical method for threshold assessment, thus contributing to the routine fitting and maintenance of cochlear implants within the limitations of a hospital setting.

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Cross-amplification was tested and variability in microsatellite primers (designed for Neotropical parrots) compared, in five macaw species, viz., three endangered blue macaws (Cyanopsitta spixii [extinct in the wild], Anodorhynchus leari [endangered] and Anodorhynchus hyacinthinus [vulnerable]), and two unthreatened red macaws (Ara chloropterus and Ara macao). Among the primers tested, 84.6% successfully amplified products in C. spixii, 83.3% in A. leari, 76.4% in A. hyacinthinus, 78.6% in A. chloropterus and 71.4% in A. macao. The mean expected heterozygosity estimated for each species, and based on loci analyzed in all the five, ranged from 0.33 (A. hyacinthinus) to 0.85 (A. macao). As expected, the results revealed lower levels of genetic variability in threatened macaw species than in unthreatened. The low combined probability of genetic identity and the moderate to high potential for paternity exclusion, indicate the utility of the microsatellite loci set selected for each macaw species in kinship and population studies, thus constituting an aid in planning in-situ and ex-situ conservation.

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OBJETIVO: avaliar a morfometria da pars da segunda vértebra cervical, verificar as variações existentes e predizer sua segurança para a colocação de parafusos por meio de uma abordagem cervical posterior. MÉTODOS: 58 vértebras foram obtidas para estudo anatômico (116 pars de C2) e foram medidas a altura e largura da pars, além do comprimento eixo-pedículo, largura e comprimento do pedículo, angulação sagital e medial. Todas as medidas foram separadas quanto aos seus lados direito e esquerdo; foi realizado o cálculo da média, variação, desvio padrão e a médica foi comparada com os estudos prévios. RESULTADOS: a largura média da pars de C2 foi de 9,5 mm; a altura, 9,5 mm; não houve diferença significativa entre os lados esquerdo e direito. O comprimento médio do pedículo foi de 10,5 mm; a medida média encontrada para o comprimento eixo-pedículo foi de 24,9 mm; a largura do pedículo foi de 2,8 mm. A angulação sagital encontrada foi de 19,6º e a horizontal foi de 28,5º. CONCLUSÕES: este estudo demonstra a viabilidade para a colocação de parafuso na pars de C2 em uma população caucasiana, destacando-se, porém, a grande variabilidade anatômica encontrada nas referidas medidas.

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The flavonoids present in sugarcane (Saccharum officinarum) extracts were analyzed by liquid chromatography - mass spectrometry (LC-MS), and a study of the fragmentation patterns of selected flavonoids was conducted using orthogonal acceleration time-of-flight electrospray ionization mass spectrometry (ESI-oa-ToF MS). Seven C- and O-glycosylflavones were identified in the extracts, namely, schaftoside, isoschaftoside, luteolin-8-C-(rhamnosylglucoside), vitexin, orientin, tricin-7-O-neohesperidoside and tricin-7-O-glucoside. Of these, five were identified in the absence of direct comparison with their respective standards. The described method also permitted the differentiation of the 6-C and 8-C isomeric flavones, schaftoside and isoschaftoside. The combination of fragmentation data and exact mass measurement showed to be complimentary to the HPLC-UV-MS techniques previously utilized for isomers discrimination in sugarcane studies.