969 resultados para False discovery rate
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Electromagnetic articulography (EMA) was used to investigate how tongue movement characteristics (i.e., velocity, acceleration, duration, distance) change with. or indeed affect, increased rates of speech. Eight young adult males repeated /ta/ and /ka/ syllables first at a moderate rate that had been modelled at three syllables per second, and then 'as fast as possible'. Distance travelled by the tongue appeared to be the principal lingual kinematic feature manipulated by the group of speakers in producing increased syllable repetition rates, with velocity found to increase, decrease or remain unchanged. Acceleration remained unchanged, except in the case of increased velocity. One participant formed an exception in terms of manipulating distance by exhibiting marginally increased lingual velocities rather than distance changes. This preliminary study serves to direct future EMA-based studies of speech rate control as to the speech tasks that should be employed and the possible underlying anatomical and acoustic bases or constraints that could possibly influence the kinematic strategies employed to increase speech rate.
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Background Wide testing of the aldosterone: renin ratio among hypertensive individuals has revealed primary aldosteronism to be common, with most patients normokalaemic. Some investigators, however, have reported aldosterone-producing adenoma to be rare among patients so detected. Objective To test the hypothesis that differences among reported studies in the rate of detection of aldosterone-producing adenoma (as opposed to bilateral adrenal hyperplasia) reflect differences in the procedures used for diagnosis of primary aldosteronism, and the methods used to identify aldosterone-producing adenomas. Methods In the newly established Princess Alexandra Hospital Hypertension Unit (PAHHU), we used procedures developed by Greenslopes Hospital Hypertension Unit (which reports that more than 30% of patients with primary aldosteronism have aldosterone-producing adenomas) to diagnose primary aldosteronism and determine the subtype. All patients with an increased aldosterone: renin ratio (measured after correction for hypokalaemia and while the patient was not receiving interfering medications) underwent fludrocortisone suppression testing to confirm or exclude primary aldosteronism; if they were positive, they underwent genetic testing to exclude glucocorticoid-remediable aldosteronism before adrenal venous sampling was used to differentiate lateralizing from bilateral primary aldosteronism. Results This approach allowed PAHHU to diagnose, within 2 years, 54 patients [only seven (13%) hypokalaemic] with primary aldosteronism. All tested negative for glucocorticoid-remediable aldosteronism. Aldosterone production was lateralized to one adrenal in 15 patients (31%; only six hypokalaemic) and was bilateral in 34 (69%; all normokalaemic) of 49 patients who underwent adrenal venous sampling. Among patients with lateralizing adrenal hyperplasia, computed tomography revealed an ipsilateral mass in only six and a contralateral lesion in one. Fourteen patients underwent unilateral adrenalectomy, which cured the hypertension in seven and improved it in the remainder. In patients with bilateral primary aldlosteronism, hypertension responded to spironolactone (112.5-50 mg/ day) or amiloride (2.5-10 mg/day). Conclusion When performed with careful regard to confounding factors, measurement of the aldosterone: renin ratio in all hypertensive individuals, followed by fludrocortisone suppression testing to confirm or exclude primary aldosteronism and adrenal venous sampling to determine the subtype, can result in the detection of significant numbers of patients with specifically treatable or potentially curable hypertension. (C) 2003 Lippincott Williams Wilkins.
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Background: The surgical cure rate for primary hyperparathyroidism is greater than 95%. For those who have recurrent or persistent disease, preoperative localization improves reoperation success rates. Selective parathyroid venous sampling (SPVS) for intact parathyroid hormone is particularly useful when non-invasive localization techniques are negative or inconclusive. Methods: We present all known cases (n = 13) between 1994 and 2002 who had venous sampling for localization at our institution prior to reoperation for recurrent or persistent primary hyperparathyroidism. Comparison was made with non-invasive localization procedures. Results of invasive and non-invasive localization were correlated with surgical findings. Results: Of the nine reoperated cases, eight had positive correlations between SPVS and operative findings and histopathology. SPVS did not reveal the parathyroid hormone source in one case with negative non-invasive localization procedures. Comparisons between SPVS, computerized tomography (CT), and parathyroid scintigraphy (MIBI) as expressed in terms of true positive (TP), false positive (FP) and false negative (FN) were: SPVS - TP 88.8%, FP 0%, FN 11.1%; CT - TP 22.2%, FP 22.2%, FN 55.5%; and MIBI - TP 33.3%, FP 0%, FN 66.6%. At least seven of the nine operated cases have been cured; another remained normocalcaemic 2 weeks after subtotal parathyroidectomy. Conclusion: In our institution SPVS has proven to be a valuable tool in cases with recurrent or persistent primary hyperparathyroidism and negative non-invasive localization procedures.
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This paper discusses a document discovery tool based on Conceptual Clustering by Formal Concept Analysis. The program allows users to navigate e-mail using a visual lattice metaphor rather than a tree. It implements a virtual. le structure over e-mail where files and entire directories can appear in multiple positions. The content and shape of the lattice formed by the conceptual ontology can assist in e-mail discovery. The system described provides more flexibility in retrieving stored e-mails than what is normally available in e-mail clients. The paper discusses how conceptual ontologies can leverage traditional document retrieval systems and aid knowledge discovery in document collections.
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The effects that four pretreatments (blanching, chilling, freezing, and combined blanching and freezing), used prior to drying, had on the drying rate and quality of bananas were investigated. An untreated sample was used as a control. The bananas were dried at 50 degreesC in a heat pump dehumidifier dryer, using an air velocity of 3.1 m s(-1), until a final moisture content of approximately 25% dry weight basis was attained. While the initial drying rate was highest for the blanched treatment, the two pretreatments involving freezing resulted in the shortest drying times. The blanched sample was most preferred in terms of colour while the frozen samples exhibited extensive browning. The texture and flavour was significantly (P < 0.05) reduced in all samples that involved blanching and/or freezing.
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A hyphenated instrumental approach has been used to obtain reliable values for the propagation rate coefficients as a function of conversion for polymerizations of methyl methacrylate (MMA) and a mixture of MMA and ethyleneglycol dimethacrylate (EGDMA) with a 1:1 concentration of double bonds, from near the onset of the Trommsdorf region into the glass region. ESR spectroscopy was used to measure the radical concentration while FT-NIR fibre-optic spectroscopy was employed to measure instantaneously the double-bond concentration within the temperature-controlled cavity of the ESR instrument during polymerization. The advantage of this approach to the measurement of the rate coefficient is that it is equally applicable to branching and linear polymerizations. For the polymerization of methyl methacrylate, the values of the rate coefficient at the lowest conversions at which reliable values could be obtained were in agreement with recently reported values obtained by the PLP-SEC method. For the lowest conversions, the values obtained were 403 1 mol(-1) s(-1) at 306 K for MMA and 5201 mol(-1) s(-1) at 310 K for a 1:1 mixture of MMA and EGDMA. (C) 2003 Society of Chemical Industry.
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COORDINSPECTOR is a Software Tool aiming at extracting the coordination layer of a software system. Such a reverse engineering process provides a clear view of the actually invoked services as well as the logic behind such invocations. The analysis process is based on program slicing techniques and the generation of, System Dependence Graphs and Coordination Dependence Graphs. The tool analyzes Common Intermediate Language (CIL), the native language of the Microsoft .Net Framework, thus making suitable for processing systems developed in any .Net Framework compilable language. COORDINSPECTOR generates graphical representations of the coordination layer together with business process orchestrations specified in WSBPEL 2.0
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Abstract: in Portugal, and in much of the legal systems of Europe, «legal persons» are likely to be criminally responsibilities also for cybercrimes. Like for example the following crimes: «false information»; «damage on other programs or computer data»; «computer-software sabotage»; «illegitimate access»; «unlawful interception» and «illegitimate reproduction of protected program». However, in Portugal, have many exceptions. Exceptions to the «question of criminal liability» of «legal persons». Some «legal persons» can not be blamed for cybercrime. The legislature did not leave! These «legal persons» are v.g. the following («public entities»): legal persons under public law, which include the public business entities; entities utilities, regardless of ownership; or other legal persons exercising public powers. In other words, and again as an example, a Portuguese public university or a private concessionaire of a public service in Portugal, can not commit (in Portugal) any one of cybercrime pointed. Fair? Unfair. All laws should provide that all legal persons can commit cybercrimes. PS: resumo do artigo em inglês.
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The current level of demand by customers in the electronics industry requires the production of parts with an extremely high level of reliability and quality to ensure complete confidence on the end customer. Automatic Optical Inspection (AOI) machines have an important role in the monitoring and detection of errors during the manufacturing process for printed circuit boards. These machines present images of products with probable assembly mistakes to an operator and him decide whether the product has a real defect or if in turn this was an automated false detection. Operator training is an important aspect for obtaining a lower rate of evaluation failure by the operator and consequently a lower rate of actual defects that slip through to the following processes. The Gage R&R methodology for attributes is part of a Six Sigma strategy to examine the repeatability and reproducibility of an evaluation system, thus giving important feedback on the suitability of each operator in classifying defects. This methodology was already applied in several industry sectors and services at different processes, with excellent results in the evaluation of subjective parameters. An application for training operators of AOI machines was developed, in order to be able to check their fitness and improve future evaluation performance. This application will provide a better understanding of the specific training needs for each operator, and also to accompany the evolution of the training program for new components which in turn present additional new difficulties for the operator evaluation. The use of this application will contribute to reduce the number of defects misclassified by the operators that are passed on to the following steps in the productive process. This defect reduction will also contribute to the continuous improvement of the operator evaluation performance, which is seen as a quality management goal.
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ABSTRACT The efficiency of nitrogen fertilizer in corn is usually low, negatively affecting plant nutrition, the economic return, and the environment. In this context, a variable rate of nitrogen, prescribed by crop sensors, has been proposed as an alternative to the uniform rate of nitrogen traditionally used by farmers. This study tested the hypothesis that variable rate of nitrogen, prescribed by optical sensor, increases the nitrogen use efficiency and grain yield as compared to uniform rate of nitrogen. The following treatments were evaluated: 0; 70; 140; and 210 kg ha-1 under uniform rate of nitrogen, and 140 kg ha -1 under variable rate of nitrogen. The nitrogen source was urea applied on the soil surface using a distributor equipped with the crop sensor. In this study, the grain yield ranged from 10.2 to 15.5 Mg ha-1, with linear response to nitrogen rates. The variable rate of nitrogen increased by 11.8 and 32.6% the nitrogen uptake and nitrogen use efficiency, respectively, compared to the uniform rate of nitrogen. However, no significant increase in grain yield was observed, indicating that the major benefit of the variable rate of nitrogen was reducing the risk of environmental impact of fertilizer.
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The essay analises Sir Walter Raleigh's report (1595) of his search for Guiana, as well as his reflection on the New World and its inhabitants, which is, in many aspects, different from his contemporaries.
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Interest rate risk is one of the major financial risks faced by banks due to the very nature of the banking business. The most common approach in the literature has been to estimate the impact of interest rate risk on banks using a simple linear regression model. However, the relationship between interest rate changes and bank stock returns does not need to be exclusively linear. This article provides a comprehensive analysis of the interest rate exposure of the Spanish banking industry employing both parametric and non parametric estimation methods. Its main contribution is to use, for the first time in the context of banks’ interest rate risk, a nonparametric regression technique that avoids the assumption of a specific functional form. One the one hand, it is found that the Spanish banking sector exhibits a remarkable degree of interest rate exposure, although the impact of interest rate changes on bank stock returns has significantly declined following the introduction of the euro. Further, a pattern of positive exposure emerges during the post-euro period. On the other hand, the results corresponding to the nonparametric model support the expansion of the conventional linear model in an attempt to gain a greater insight into the actual degree of exposure.