An Extended Pearson System Useful In Reliability Analysis

In the present environment, industry should provide the products of high quality. Quality of products is judged by the period of time they can successfully perform their intended functions without failure. The cause of the failures can be ascertained through life testing experiments and the times to failure due to different cause are likely to follow different distributions. Knowledge of this distribution is essential to eliminate causes of failures and thereby to improve the quality and the reliability of products. The main accomplishment expected to the study is to develop statistical tools that could facilitate solution to lifetime data arising in such and similar contexts

Monolithic fused 1 x 4 couplers with high uniformity

A new method for the fabrication of high uniformity monolithic 1 x 4 single mode fused coupler is described together with details of its performance in terms of coupling ratio, spectral response and uniformity. The fabricated device exhibits ultra-broadband performance with a port-to-port uniformity of 0.4 dB. The reliability of such couplers is also evaluated and found to have good stability. Moreover, by controlling the process parameters it is possible to control the power remaining in the through put port of the device, which can be used for dedicated non-intrusive network health monitoring.

Monolithic fused 1 x 4 couplers with high uniformity

A new method for the fabrication of high uniformity monolithic 1 x4 single-mode fused coupler is described together with details of its performance in terms of coupling ratio, spectral response and uniformity. The fabricated device exhibits ultra-broadband performance with a port-to-port uniformity of 0.4 dB. The reliability of such couplers is also evaluated and found to have good stability. Moreover, by controlling the process parameters it is possible to control the power remaining in the through put port of the device, which can be used for dedicated non-intrusive network health monitoring

Reliability of the Brief Neuropsychological Assessment Instrument Neupsilin

This study aimed to evaluate the reliability of Neupsilin Brief Neuropsychological Assessment Instrument, a brief battery developed in Brazil. Hundred two Brazilian man and women participated, from 18 to 40 years of age. It was evaluated the test-retest reliability of the Neupsilin tasks and the reliability of the correction of the constructional praxis task by different evaluators. The data were analyzed by Spearman’s correlation, intraclass correlation and Cronbach’s alpha. Language, memory, praxis and executive functions presented the highest correlations in the test-retest analyses. The agreement in the correction of the constructional praxis task was moderate to high. The results indicate temporal reliability of Neupsilin tasks and inter-rater agreement in the correction of the constructional praxis task. Suggestions to improve the tasks, the validity and reliability of Neupsilin were presented.

On reliability analysis of multi-categorical forecasts

Reliability analysis of probabilistic forecasts, in particular through the rank histogram or Talagrand diagram, is revisited. Two shortcomings are pointed out: Firstly, a uniform rank histogram is but a necessary condition for reliability. Secondly, if the forecast is assumed to be reliable, an indication is needed how far a histogram is expected to deviate from uniformity merely due to randomness. Concerning the first shortcoming, it is suggested that forecasts be grouped or stratified along suitable criteria, and that reliability is analyzed individually for each forecast stratum. A reliable forecast should have uniform histograms for all individual forecast strata, not only for all forecasts as a whole. As to the second shortcoming, instead of the observed frequencies, the probability of the observed frequency is plotted, providing and indication of the likelihood of the result under the hypothesis that the forecast is reliable. Furthermore, a Goodness-Of-Fit statistic is discussed which is essentially the reliability term of the Ignorance score. The discussed tools are applied to medium range forecasts for 2 m-temperature anomalies at several locations and lead times. The forecasts are stratified along the expected ranked probability score. Those forecasts which feature a high expected score turn out to be particularly unreliable.

High-resolution electrocardiography in the diagnosis of arrhythmogenic right ventricular cardiomyopathy in Boxer dogs

Com o objetivo de avaliar a importância da eletrocardiografia de alta resolução no diagnóstico da cardiomiopatia arritmogênica do ventrículo direito do Boxer, 20 cães sem evidências de doença cardíaca estrutural à avaliação ecodopplercardiográfica foram agrupados de acordo com a frequência de arritmias ventriculares, avaliadas pela eletrocardiografia ambulatorial de 24 horas, e submetidos ao exame eletrocardiográfico de alta resolução. Duração do complexo QRS filtrado, duração dos sinais de baixa amplitude (menor que 40µV) dos últimos 40 milissegundos do complexo QRS e raiz quadrada média da voltagem ao quadrado dos últimos 40 milissegundos do complexo QRS (RMS40) foram as variáveis avaliadas. Não foram observadas diferenças significativas entre os grupos em relação às variáveis estudadas. Sendo assim, os resultados do presente estudo sugerem que a eletrocardiografia de alta resolução não é uma ferramenta útil no auxílio diagnóstico da cardiomiopatia arritmogênica do ventrículo direito dos cães da raça Boxer que não apresentam alterações miocárdicas evidentes ou disfunção sistólica.

Single-phase high power factor hybrid rectifier suitable for high-power applications

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

In vitro propagation of Maytenus ilicifolia (Celastraceae) as potential source for antitumoral and antioxidant quinomethide triterpenes production. A rapid quantitative method for their analysis by reverse-phase high-performance liquid chromatography

Cell culture of Maytenus ilicifolia were established in order to produce and to quantify the antitumoral and antioxidant quinonemethide triterpenes. In vitro calli were induced from leaf explants of native plants and cultured in semi-solid medium under controlled conditions of humidity, temperature and photoperiod. The quinonemethide triterpenes showed maximum accumulation in the logarithmic phase growth of the cell culture. A rapid, sensitive and reliable reverse-phase HPLC method was used for quantitative determination of the antitumoral and antioxidant quinonemethide triterpenes, 22β-hydroxymaytenin and maytenin in callus of Maytenus ilicifolia. Well resolved peaks with good detection response and linearity in the range 1.0 - 100 μg/mL were obtained. This quantitative work was performed by an external standard method.

The Brazilian version of the Neuropsychiatric Inventory-Clinician rating scale (NPI-C): Reliability and validity in dementia

ABSTRACT Background: Patients with dementia may be unable to describe their symptoms, and caregivers frequently suffer emotional burden that can interfere with judgment of the patient's behavior. The Neuropsychiatric Inventory-Clinician rating scale (NPI-C) was therefore developed as a comprehensive and versatile instrument to assess and accurately measure neuropsychiatric symptoms (NPS) in dementia, thereby using information from caregiver and patient interviews, and any other relevant available data. The present study is a follow-up to the original, cross-national NPI-C validation, evaluating the reliability and concurrent validity of the NPI-C in quantifying psychopathological symptoms in dementia in a large Brazilian cohort. Methods: Two blinded raters evaluated 312 participants (156 patient-knowledgeable informant dyads) using the NPI-C for a total of 624 observations in five Brazilian centers. Inter-rater reliability was determined through intraclass correlation coefficients for the NPI-C domains and the traditional NPI. Convergent validity included correlations of specific domains of the NPI-C with the Brief Psychiatric Rating Scale (BPRS), the Cohen-Mansfield Agitation Index (CMAI), the Cornell Scale for Depression in Dementia (CSDD), and the Apathy Inventory (AI). Results: Inter-rater reliability was strong for all NPI-C domains. There were high correlations between NPI-C/delusions and BPRS, NPI-C/apathy-indifference with the AI, NPI-C/depression-dysphoria with the CSDD, NPI-C/agitation with the CMAI, and NPI-C/aggression with the CMAI. There was moderate correlation between the NPI-C/aberrant vocalizations and CMAI and the NPI-C/hallucinations with the BPRS. Conclusion: The NPI-C is a comprehensive tool that provides accurate measurement of NPS in dementia with high concurrent validity and inter-rater reliability in the Brazilian setting. In addition to universal assessment, the NPI-C can be completed by individual domains. © International Psychogeriatric Association 2013.

The reliability of counting actinic keratosis

Many epidemiological studies and clinical trials have been performed concerning actinic keratoses. The most eligible endpoint in the majority of articles is counting of actinic keratoses before and after treatments, nevertheless some authors support that this is not a reliable form of evaluation. The aim of this study was to evaluate the actinic keratoses counting by various raters and suggest approaches to increase the reliability. Cross-sectional study: forty-three patients were evaluated by four raters (inter- and intra-rater assessment) on the face and forearms. The mean actinic keratoses counts on the face and forearms were 7.7 and 9.1. The overall agreement among the raters for the facial and forearm actinic keratoses was 0.74 and 0.77. The intra-rater assessment showed high rates of agreement for the face (ICC = 0.93) and forearms (ICC = 0.83). Higher agreement occurred when counting up to five lesions. Four raters led to increased measurement variability and loss of reliability. Higher rates of agreement may be achieved with small number of lesions, limitation and/or segmentation of body areas to reduce their number, in AK prevention designs, are strategies that may lead to a greater reliability of these measurements. © 2013 Springer-Verlag Berlin Heidelberg.

Reliability of marginal microleakage assessment by visual and digital methods

The aim of this study was to investigate the reliability of visual and digital methods to assess marginal microleakage in vitro. Materials and Methods: Typical Class V preparations were made in bovine teeth and filled with composite resin. After dye penetration (0.5% basic fuchsin), teeth were sectioned and the 53 obtained fragments were assessed according to visual (stereomicroscope) and digital methods (Image Tool Software ® -ITS) (University of Texas Health Science Center-San Antonio Dental School, USA). Two calibrated examiners (A and B) evaluated dye penetration, by means of a stereomicroscope with ×20 magnification (scores), and by the ITS (millimeters). The intra- and inter-examiner agreement was estimated according to Kappa statistics (κ), and intraclass correlation coefficient (ρ). Results: In relation to the visual method, the intra-examiner agreement was almost perfect (κA = 0.87) and substantial (κB = 0.76), respectively to the examiner A and B. The inter-examiner agreement showed an almost perfect reliability (κ = 0.84). For the digital method, the intra-examiner agreement was almost perfect for both examiners and equal to ρ = 0.99, and so was the inter-examiner agreement value. Conclusion: Visual (stereomicroscope) and digital methods (ITS) showed high levels of intra- and inter-examiner reproducibility when marginal microleakage was assessed.

Reliability and differentiation capability of dynamic and static kinematic measurements of rearfoot eversion in patellofemoral pain

Excessive rearfoot eversion is thought to be a risk factor for patellofemoral pain development, due to the kinesiological relationship with ascendant adaptations. Individuals with patellofemoral pain are often diagnosed through static clinical tests, in scientific studies and clinical practice. However, the adaptations seem to appear in dynamic conditions. Performing static vs. dynamic evaluations of widely used measures would add to the knowledge in this area. Thus, the aim of this study was to determine the reliability and differentiation capability of three rearfoot eversion measures: rearfoot range of motion, static clinical test and static measurement using a three-dimensional system. A total of 29 individuals with patellofemoral pain and 25 control individuals (18-30 years) participated in this study. Each subject underwent three-dimensional motion analysis during stair climbing and static clinical tests. Intraclass correlation coefficient and standard error measurements were performed to verify the reliability of the variables and receiver operating characteristic curves to show the diagnostic accuracy of each variable. In addition, analyses of variance were performed to identify differences between groups. Rearfoot range of motion demonstrated higher diagnostic accuracy (an area under the curve score of 0.72) than static measures and was able to differentiate the groups. Only the static clinical test presented poor and moderate reliability. Other variables presented high to very high values. Rearfoot range of motion was the variable that presented the best results in terms of reliability and differentiation capability. Static variables do not seem to be related to patellofemoral pain and have low accuracy values.

Reliable assessment of forearm photoageing by high-frequency ultrasound: a cross-sectional study

High-frequency ultrasound is a non-invasive tool used in skin ageing research to assess dermis thickness and echogenicity. This study evaluated the reliability of a range of high-frequency ultrasound parameters and tested their correlation with age and a validated clinical scale for the assessment of forearm skin photoageing; the difference between two body sites according to environmental exposition patterns was also investigated. Twenty-three volunteers aged 28-82 years were divided into three groups according to forearm photoageing degree. A 20 MHz ultrasound unit was used to obtain cross-sectional images of the skin by two trained investigators on two different sites: the dorsal forearm (chronically photoexposed skin) and the proximal medial arm (non-photoexposed skin). Several echogenicity parameters were studied for each skin compartment: total dermis, upper dermis and lower dermis, and the ratio between upper and lower dermis. The intraclass correlation coefficient (for complete agreement) between investigators was higher for upper and total dermis echogenicity measures compared with the lower dermis. At the non-photoexposed site, the upper and lower dermis parameter ratio was better correlated with age. At the photoexposed area, total dermis parameters demonstrated higher correlations with clinical score. The authors discuss the choice of parameters for forearm photoageing assessment using high-frequency ultrasound.

High levels of C-reactive protein are associated with reduced vagal modulation and low physical activity in young adults

The purpose of this study was to examine the relationship between cardiac autonomic control derived from heart rate variability (HRV), high-sensitivity C-reactive protein (hs-CRP) and physical activity (PA) levels measured using accelerometers. A total of 80 healthy university students volunteered to participate in this study (20.56 +/- 0.82 years, 1.36 +/- 1.5 mg/L of hs-CRP). The participants were divided into groups based on tertiles of hs-CRP. Analysis of covariance adjusted to PA was used to assess group differences in HRV. Associations between hs-CRP, HRV indices and PA were analyzed using Pearson's correlation. The participants at the highest tertile of hs-CRP (tertile 3) had lower cardiac vagal modulation (SDNN, tertile 1=78.05 +/- 5.9,tertile 2=82.43 +/- 5.9,tertile 3=56.03 +/- 6.1; SD1, tertile 1=61.27 +/- 5.3, tertile 2=62.93 +/- 5.4, tertile 3=40.03 +/- 5.5). In addition, vagal indices were inversely correlated with hs-CRP but positively correlated with PA (SDNN r=-0.320, SD1 r=-0.377; SDNN r=0.304, SD1 r=0.299; P<0.05). Furthermore, the most physically active subjects had lower levels of hs-CRP and the highest levels of vagal modulation.