The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Stephen S Lefrak - One of the best experts on this subject based on the ideXlab platform.
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results of lung volume reduction surgery in patients meeting a national emphysema treatment trial high Risk Criterion
The Journal of Thoracic and Cardiovascular Surgery, 2004Co-Authors: Bryan F Meyers, Stephen S Lefrak, Tracey J Guthrie, Roger D Yusen, Alexander G PattersonAbstract:Abstract Objectives A report from the National Emphysema Treatment Trial indicated that lung volume reduction candidates with a forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of 20% or less of predicted value were at high Risk for mortality and were unlikely to benefit from surgical intervention. This article examines the applicability of the National Emphysema Treatment Trial findings to our own patients. Methods We reviewed 280 patients who underwent bilateral lung volume reduction surgery at our institution between January 1993 and December 2001. All patients met our selection criteria, including heterogeneous distribution of emphysema. Of these 280 patients, 20 patients had both a preoperative forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of less than or equal to 20% of the predicted normal values, thus meeting one National Emphysema Treatment Trial Criterion for high Risk. Outcomes of the 20 patients were assessed through 5 years after the operation. The survival of the 20 patient cohort was compared with that of the 260 patients not meeting the National Emphysema Treatment Trial high-Risk Criterion. Results Ninety-day operative mortality included 1 (5%) patient. In all patients the forced expiratory volume in 1 second increased from 0.46 L (17%) to 0.78 L (32%), a 73% change; the diffusing capacity of carbon monoxide increased from 16% to 27%, a 70% improvement; residual volume decreased from 6.33 L (305%) to 4.26 L (205%), a 33% improvement; and room air arterial partial pressure of oxygen increased from 55 mm Hg to 64 mm Hg. Kaplan-Meier 5-year survivals did not differ between the high-Risk and non–high-Risk groups. Conclusions Patients with a forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of 20% or less of predicted value might experience improvements in lung function, exercise tolerance, and quality of life with acceptable morbidity and mortality after lung volume reduction surgery.
Bryan F Meyers - One of the best experts on this subject based on the ideXlab platform.
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results of lung volume reduction surgery in patients meeting a national emphysema treatment trial high Risk Criterion
The Journal of Thoracic and Cardiovascular Surgery, 2004Co-Authors: Bryan F Meyers, Stephen S Lefrak, Tracey J Guthrie, Roger D Yusen, Alexander G PattersonAbstract:Abstract Objectives A report from the National Emphysema Treatment Trial indicated that lung volume reduction candidates with a forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of 20% or less of predicted value were at high Risk for mortality and were unlikely to benefit from surgical intervention. This article examines the applicability of the National Emphysema Treatment Trial findings to our own patients. Methods We reviewed 280 patients who underwent bilateral lung volume reduction surgery at our institution between January 1993 and December 2001. All patients met our selection criteria, including heterogeneous distribution of emphysema. Of these 280 patients, 20 patients had both a preoperative forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of less than or equal to 20% of the predicted normal values, thus meeting one National Emphysema Treatment Trial Criterion for high Risk. Outcomes of the 20 patients were assessed through 5 years after the operation. The survival of the 20 patient cohort was compared with that of the 260 patients not meeting the National Emphysema Treatment Trial high-Risk Criterion. Results Ninety-day operative mortality included 1 (5%) patient. In all patients the forced expiratory volume in 1 second increased from 0.46 L (17%) to 0.78 L (32%), a 73% change; the diffusing capacity of carbon monoxide increased from 16% to 27%, a 70% improvement; residual volume decreased from 6.33 L (305%) to 4.26 L (205%), a 33% improvement; and room air arterial partial pressure of oxygen increased from 55 mm Hg to 64 mm Hg. Kaplan-Meier 5-year survivals did not differ between the high-Risk and non–high-Risk groups. Conclusions Patients with a forced expiratory volume in 1 second and a diffusing capacity of carbon monoxide of 20% or less of predicted value might experience improvements in lung function, exercise tolerance, and quality of life with acceptable morbidity and mortality after lung volume reduction surgery.
De-shuang Huang - One of the best experts on this subject based on the ideXlab platform.
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Dimensionality reduction based on minimax Risk Criterion for face recognition
The 2010 International Joint Conference on Neural Networks (IJCNN), 2010Co-Authors: Lei Tang, De-shuang HuangAbstract:In the field of pattern recognition and machine learning, many problems are involved in the tasks of dimensionality reduction and then classification. In this paper, we develop an efficient dimensionality reduction method named MiniRisk Supervised Discrimiant Projection (MRSDP), which extracts effective low-dimensional features for classification purpose. The proposed method utilizes discriminant information to guide the procedure of extracting intrinsic low-dimensional features and provides a linear projection matrix. Since MRSDP is based on minimax Risk Criterion, it can minimize the maximal probability of misclassification in the common borders of different classes of data by contracting within-class scatter and maximizing between-class scatter. The advantage of our method is borne out by comparison with other widely used methods. In the experiments on Yale face database and ORL face database, our method achieves constantly superior performance than those competing methods.
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IJCNN - Dimensionality reduction based on minimax Risk Criterion for face recognition
The 2010 International Joint Conference on Neural Networks (IJCNN), 2010Co-Authors: Lei Tang, De-shuang HuangAbstract:In the field of pattern recognition and machine learning, many problems are involved in the tasks of dimensionality reduction and then classification. In this paper, we develop an efficient dimensionality reduction method named MiniRisk Supervised Discrimiant Projection (MRSDP), which extracts effective low-dimensional features for classification purpose. The proposed method utilizes discriminant information to guide the procedure of extracting intrinsic low-dimensional features and provides a linear projection matrix. Since MRSDP is based on minimax Risk Criterion, it can minimize the maximal probability of misclassification in the common borders of different classes of data by contracting within-class scatter and maximizing between-class scatter. The advantage of our method is borne out by comparison with other widely used methods. In the experiments on Yale face database and ORL face database, our method achieves constantly superior performance than those competing methods.
Arturo J. Fernández - One of the best experts on this subject based on the ideXlab platform.
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Classical versus Bayesian Risks in acceptance sampling: a sensitivity analysis
Computational Statistics, 2012Co-Authors: Carlos J. Pérez-gonzález, Arturo J. FernándezAbstract:Assuming a beta prior distribution on the fraction defective, \(p\), failure-censored sampling plans for Weibull lifetime models using classical (or average) and Bayesian (or posterior) producer’s and consumer’s Risks are designed to determine the acceptability of lots of a given product. The average Risk Criterion provides a certain assurance that good (bad) lots will be accepted (rejected), whereas the posterior Risk Criterion provides a determined confidence that an accepted (rejected) lot is indeed good (bad). The performance of classical and Bayesian Risks are analyzed in developing sampling plans when the lifetime variable follows the Weibull distribution. Several figures and tables illustrate the sensitivity of the Risks and optimal sample sizes for selected censoring levels and specifications according to the available prior information on \(p\). The analysis clarifies the distinction among the different Risks for a given sampling plan, and the effect of the prior knowledge on the required sample size. The study shows that, under uncertainty in the prior variance of \(p\), the designs using Bayesian Risks are more appropriate.
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Classical versus Bayesian Risks in acceptance sampling: a sensitivity analysis
Computational Statistics, 2012Co-Authors: Carlos J. Pérez-gonzález, Arturo J. FernándezAbstract:Assuming a beta prior distribution on the fraction defective, $$p$$ , failure-censored sampling plans for Weibull lifetime models using classical (or average) and Bayesian (or posterior) producer’s and consumer’s Risks are designed to determine the acceptability of lots of a given product. The average Risk Criterion provides a certain assurance that good (bad) lots will be accepted (rejected), whereas the posterior Risk Criterion provides a determined confidence that an accepted (rejected) lot is indeed good (bad). The performance of classical and Bayesian Risks are analyzed in developing sampling plans when the lifetime variable follows the Weibull distribution. Several figures and tables illustrate the sensitivity of the Risks and optimal sample sizes for selected censoring levels and specifications according to the available prior information on $$p$$ . The analysis clarifies the distinction among the different Risks for a given sampling plan, and the effect of the prior knowledge on the required sample size. The study shows that, under uncertainty in the prior variance of $$p$$ , the designs using Bayesian Risks are more appropriate. Copyright Springer-Verlag 2013
Michael Eisenhut - One of the best experts on this subject based on the ideXlab platform.
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Risk of treatment delay in patients suspected of sepsis with moderate to high Risk criteria
BMJ, 2016Co-Authors: Michael EisenhutAbstract:In the recently published NICE sepsis guidance the authors outline pathways of management stratified according to Risk of severe illness and death.1 2 They recommend that patients with one moderate to high Risk Criterion without a definitive condition do not automatically receive early antibiotic administration within an hour but do undergo senior clinician review within three hours for consideration of antibiotics. One such moderate to high Risk Criterion is behaving differently from usual. A child with fever and altered behaviour, however, could have encephalitis. The consensus guidelines of the Association …
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Risk of treatment delay in patients suspected of sepsis with moderate to high Risk criteria
BMJ, 2016Co-Authors: Michael EisenhutAbstract:In the recently published NICE sepsis guidance the authors outline pathways of management stratified according to Risk of severe illness and death.1 2 They recommend that patients with one moderate to high Risk Criterion without a definitive condition do not automatically receive early antibiotic administration within an hour but do undergo senior clinician review within three hours for consideration of antibiotics. One such moderate to high Risk Criterion is behaving differently from usual. A child with fever and altered behaviour, however, could have encephalitis. The consensus guidelines of the Association …
