Variable interactions and exploring parameter space in an expensive optimisation problem: Optimising Short Term Conflict Alert

Copyright © 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works.2010 IEEE Congress on Evolutionary Computation (CEC), Barcelona, Spain, 18-23 July 2010Short Term Conflict Alert (STCA) systems provide warnings to air traffic controllers if aircraft are in danger of becoming too close. They are complex software programs, with many inter-dependent parameters that must be adjusted to achieve the best trade-off between wanted and nuisance alerts. We describe a multi-archive evolutionary algorithm for optimising regional parameter subsets in parallel, reducing the number of evaluations required to generate an estimated Pareto optimal Receiver Operating Characteristic (ROC), showing that it provides superior results to traditional single-archived algorithms. A method of `aggressive' optimisation, designed to explore unknown parameter ranges in a `safe' manner, is shown to yield more extensive and better converged estimated Pareto fronts

The Performance Effects of Word Locator Cues on the NAEP Reading Assessment

Beginning with the 2009 National Assessment of Educational Progress (NAEP) reading assessment, a new subset of items will be introduced with the intent of measuring vocabulary in context. The assessment’s item format requires an examinee to locate a targeted word in the reading passage. It was reasoned that presenting these items along with ‘word locator cues’ might help reduce construct irrelevant variance due to students’ differential ability in searching the targeted word. Using a sample of 1323 fourth and eight grade students, this study investigated the effects of two such ‘word locator cues’ on student performance: numbering the lines of the passage, and printing targeted words in boldface type. The results indicated that various format conditions (with and without cues) do not influence student performance on the vocabulary items after controlling for reading comprehension. On the other hand, at both fourth and eighth grade, we detected interactions between format conditions and race/ethnicity, which suggested that word locator cues appear to hurt the performance of certain subgroups. Implications of these findings for NAEP’s future reading assessments are discussed. Accessed 11,314 times on https://pareonline.net from October 04, 2007 to December 31, 2019. For downloads from January 1, 2020 forward, please click on the PlumX Metrics link to the right

Assessment and optimisation of STCA performance: Using the Pareto optimal receiver operating characteristic

EUROCONTROL Annual Safety R&D Seminar (2008), Southampton, UK, 22-24 October 2008Short Term Conflict Alert (STCA) systems are complex software programs, with many parameters that must be adjusted to achieve best performance. We describe a simple evolutionary algorithm for optimising the trade-off between wanted alerts and nuisance alerts. The procedure yields an estimate of the Pareto optimal Receiver Operating Characteristic for the STCA system and we discuss additional uses of this for characterising and comparing the performance of STCA systems and airspaces

Validation of vessel size imaging (VSI) in high-grade human gliomas using magnetic resonance imaging, image-guided biopsies, and quantitative immunohistochemistry.

To evaluate the association between a vessel size index (VSIMRI) derived from dynamic susceptibility contrast (DSC) perfusion imaging using a custom spin-and-gradient echo echoplanar imaging (SAGE-EPI) sequence and quantitative estimates of vessel morphometry based on immunohistochemistry from image-guided biopsy samples. The current study evaluated both relative cerebral blood volume (rCBV) and VSIMRI in eleven patients with high-grade glioma (7 WHO grade III and 4 WHO grade IV). Following 26 MRI-guided glioma biopsies in these 11 patients, we evaluated tissue morphometry, including vessel density and average radius, using an automated procedure based on the endothelial cell marker CD31 to highlight tumor vasculature. Measures of rCBV and VSIMRI were then compared to histological measures. We demonstrate good agreement between VSI measured by MRI and histology; VSIMRI = 13.67 μm and VSIHistology = 12.60 μm, with slight overestimation of VSIMRI in grade III patients compared to histology. rCBV showed a moderate but significant correlation with vessel density (r = 0.42, p = 0.03), and a correlation was also observed between VSIMRI and VSIHistology (r = 0.49, p = 0.01). The current study supports the hypothesis that vessel size measures using MRI accurately reflect vessel caliber within high-grade gliomas, while traditional measures of rCBV are correlated with vessel density and not vessel caliber

Evolution of hepatic steatosis in patients with advanced hepatitis C: Results from the hepatitis C antiviral long-term treatment against cirrhosis (HALT-C) trial

Hepatic steatosis is a common histologic feature in patients with chronic hepatitis C (CHC) but there are no large longitudinal studies describing the progression of steatosis in CHC. We examined changes in steatosis on serial biopsies among CHC patients participating in the Hepatitis C Antiviral Long-term Treatment against Cirrhosis (HALT-C) Trial. All 1050 patients in the trial had advanced fibrosis at baseline biopsy and were documented not to have had a sustained virological response to peginterferon and ribavirin. Most (94%) patients had genotype 1 infection. At least one protocol follow-up biopsy was read on 892 patients, and 699 had the last biopsy performed 3.5 years after randomization. At enrollment, 39% had cirrhosis and 61% had bridging fibrosis; 18%, 41%, 31%, and 10% had steatosis scores of 0, 1, 2, and 3 or 4, respectively. The mean steatosis score decreased in the follow-up biopsies in both the interferon-treated patients and controls with no effect of treatment assignment ( P = 0.66). A decrease in steatosis score by ≥1 point was observed in 30% of patients and was associated with both progression to cirrhosis and continued presence of cirrhosis ( P = 0.02). Compared to patients without a decrease in steatosis, those with a decrease in steatosis had worse metabolic parameters at enrollment, and were more likely to have a decrease in alcohol intake, improvement in metabolic parameters, and worsening liver disease (cirrhosis, esophageal varices, and deterioration in liver function). Conclusion: Serial biopsies demonstrated that in patients with CHC, steatosis recedes during progression from advanced fibrosis to cirrhosis. Decreased alcohol intake and improved metabolic parameters are associated with a decline in steatosis and may modulate hepatitis C progression. (H EPATOLOGY 2009.)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63058/1/22865_ftp.pd

Sofosbuvir and Ribavirin Prevent Recurrence of HCV Infection After Liver Transplantation: An Open-Label Study

Background & AimsPatients with detectable hepatitis C virus (HCV) RNA at the time of liver transplantation universally experience recurrent HCV infection. Antiviral treatment before transplantation can prevent HCV recurrence, but existing interferon-based regimens are poorly tolerated and are either ineffective or contraindicated in most patients. We performed a trial to determine whether sofosbuvir and ribavirin treatment before liver transplantation could prevent HCV recurrence afterward.MethodsIn a phase 2, open-label study, 61 patients with HCV of any genotype and cirrhosis (Child–Turcotte–Pugh score, ≤7) who were on waitlists for liver transplantation for hepatocellular carcinoma, received up to 48 weeks of sofosbuvir (400 mg) and ribavirin before liver transplantation. The primary end point was the proportion of patients with HCV-RNA levels less than 25 IU/mL at 12 weeks after transplantation among patients with this HCV-RNA level at their last measurement before transplantation.ResultsSixty-one patients received sofosbuvir and ribavirin, and 46 received transplanted livers. The per-protocol efficacy population consisted of 43 patients who had HCV-RNA level less than 25 IU/mL at the time of transplantation. Of these 43 patients, 30 (70%) had a post-transplantation virologic response at 12 weeks, 10 (23%) had recurrent infection, and 3 (7%) died (2 from nonfunction of the primary graft and 1 from complications of hepatic artery thrombosis). Of all 61 patients given sofosbuvir and ribavirin, 49% had a post-transplantation virologic response. Recurrence was related inversely to the number of consecutive days of undetectable HCV RNA before transplantation. The most frequently reported adverse events were fatigue (in 38% of patients), headache (23%), and anemia (21%).ConclusionsAdministration of sofosbuvir and ribavirin before liver transplantation can prevent post-transplant HCV recurrence. ClinicalTrials.gov: NCT01559844

ADESÃO AO TRATAMENTO FISIOTERAPÊUTICO EM ADOLESCENTES COM FIBROSE CÍSTICA

Objetivo: Avaliar o grau de adesão ao tratamento fisioterapêutico em adolescentes com Fibrose Cística (FC) acompanhados em um programa multidisciplinar. Método: Estudo observacional de corte transversal com 14 pacientes do ambulatório multidisciplinar de FC no período de maio de 2016 a outubro de 2016. Foi aplicado um questionário próprio para determinar a adesão da fisioterapia; conjuntamente com a adesão do medicamento alfadornase, analisada através do Teste de Morisky-Green e a gravidade da doença, foi avaliada pela aplicação do Escore de Shwachman-Kulczycki. Resultados: A idade média dos pacientes foi de 15 anos, sendo 8 (57,1%) do sexo masculino. De acordo com o grau de adesão, 5 (35,7%) foram classificados com baixa adesão, 4 (28,6%) com moderada adesão e 5 (35,7%) com alta adesão. O escore de Shwachman-Kulczycki foi classificado em excelente 6 (48,8%), bom 4 (28,5%), leve 3 (21,4%), moderado 1 (7,1%). No presente estudo não foi observada correlação da adesão da fisioterapia com o escore de gravidade, e também com o uso da medicação alfadornase. Conclusão: Foi observada adesão satisfatória (moderada a alta) para fisioterapia respiratória em 64,3% dos adolescentes com FC investigados. No entanto, notou-se um equilíbrio entre baixa adesão e alta adesão (35,7%) para esse tratamento

The Sample Analysis at Mars Investigation and Instrument Suite

The Sample Analysis at Mars (SAM) investigation of the Mars Science Laboratory(MSL) addresses the chemical and isotopic composition of the atmosphere and volatilesextracted from solid samples. The SAM investigation is designed to contribute substantiallyto the mission goal of quantitatively assessing the habitability of Mars as an essentialstep in the search for past or present life on Mars. SAM is a 40 kg instrument suite locatedin the interior of MSLs Curiosity rover. The SAM instruments are a quadrupole massspectrometer, a tunable laser spectrometer, and a 6-column gas chromatograph all coupledthrough solid and gas processing systems to provide complementary information on thesame samples. The SAM suite is able to measure a suite of light isotopes and to analyzevolatiles directly from the atmosphere or thermally released from solid samples. In additionto measurements of simple inorganic compounds and noble gases SAM will conducta sensitive search for organic compounds with either thermal or chemical extraction fromsieved samples delivered by the sample processing system on the Curiosity rovers roboticarm

RESISTÊNCIA AERÓBIA MUSCULAR PERIFÉRICA E CAPACIDADE FUNCIONAL EM IDOSOS COM DOENÇA PULMONAR OBSTRUTIVA CRÔNICA

The objective was to evaluate the peripheral muscular aerobic resistance of elderly people with Chronic Obstructive Pulmonary Disease (COPD) and to correlate it with the functional capacity. Anthropometric and clinical data, functional capacity and peripheral muscular aerobic resistance were evaluated, setting p≤ 0.05. The sample consisted of 14 individuals with COPD, presented London Chest Activity of Daily Living (LCADL) with impairment rates, 6-minute walk test (6MWT) within the normal range, TGlittre score below the reference values. 6MWT and TGlittre did not present a significant correlation with the performance time or the number of repetitions of the PPT. The evaluation of peripheral muscular resistance through the PPT was made difficult by the lack of reference values in the literature for the age group of the study population, however, a moderate significant correlation was found between the LCADL scale with the number of repetitions and the time of the PPT.El objetivo fue evaluar la resistencia aeróbica muscular periférica de ancianos con Enfermedad Pulmonar Obstructiva Crónica (EPOC) y correlacionarla con la capacidad funcional. Se evaluaron datos antropométricos, clínicos, capacidad funcional y resistencia aeróbica muscular periférica, fijándose una p≤ 0,05. La muestra estuvo compuesta por 14 personas con EPOC, presentaban London Chest Activity of Daily Living (LCADL) con tasas de deterioro, prueba de caminata de 6 minutos (6MWT) dentro del rango normal, puntaje TGlittre por debajo de los valores de referencia. 6MWT y TGlittre no presentaron una correlación significativa con el tiempo de ejecución o el número de repeticiones del PPT. La evaluación de la resistencia muscular periférica a través de la PPT se vio dificultada por la falta de valores de referencia en la literatura para el grupo etario de la población de estudio, sin embargo, se encontró una correlación significativa moderada entre la escala LCADL con el número de repeticiones y la hora del PPT.Objetivou-se avaliar a resistência aeróbia muscular periférica de idosos com Doença Pulmonar Obstrutiva Crônica (DPOC) e correlacionar com a capacidade funcional. Foram avaliados dados antropométricos e clínicos, capacidade funcional e resistência aeróbia muscular periférica, fixando-se o p≤ 0,05. A amostra foi composta por 14 indivíduos com DPOC, apresentaram London Chest Activity of Daily Living (LCADL) com índices de comprometimento, Teste de Caminhada de 6 minutos (TC6min) dentro da normalidade, escore de TGlittre abaixo dos valores de referência. TC6min e o TGlittre não apresentaram correlação significativa com o tempo de realização ou a quantidade de repetições do TPP. A avaliação da resistência muscular periférica através do TPP foi dificultada por não haver na literatura valores de referência para a faixa etária da população do estudo, porém foi encontrada uma correlação significativa moderada entre a escala LCADL com o número de repetições e o tempo do TPP