Strongly enhanced colorectal cancer risk stratification by combining family history and genetic risk score

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Weigl K

2018-01-01

Full Text Available Korbinian Weigl,1,2 Jenny Chang-Claude,3,4 Phillip Knebel,5 Li Hsu,6 Michael Hoffmeister,1 Hermann Brenner1,2,7 1Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ, Heidelberg, 2German Cancer Consortium (DKTK, German Cancer Research Center (DKFZ, Heidelberg, 3Unit of Genetic Epidemiology, German Cancer Research Center (DKFZ, Heidelberg, 4University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, 5Department for General, Visceral and Transplantation Surgery, University Heidelberg, Heidelberg, Germany; 6Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA; 7Division of Preventive Oncology, German Cancer Research Center (DKFZ and National Center for Tumor Diseases (NCT, Heidelberg, Germany Background and aim: Family history (FH and genetic risk scores (GRSs are increasingly used for risk stratification for colorectal cancer (CRC screening. However, they were mostly considered alternatively rather than jointly. The aim of this study was to assess the potential of individual and joint risk stratification for CRC by FH and GRS.Patients and methods: A GRS was built based on the number of risk alleles in 53 previously identified single-nucleotide polymorphisms among 2,363 patients with a first diagnosis of CRC and 2,198 controls in DACHS [colorectal cancer: chances for prevention through screening], a population-based case-control study in Germany. Associations between GRS and FH with CRC risk were quantified by multiple logistic regression.Results: A total of 316 cases (13.4% and 214 controls (9.7% had a first-degree relative (FDR with CRC (adjusted odds ratio [aOR] 1.86, 95% CI 1.52–2.29. A GRS in the highest decile was associated with a 3.0-fold increased risk of CRC (aOR 3.00, 95% CI 2.24–4.02 compared with the lowest decile. This association was tentatively more pronounced in older age groups. FH and GRS were essentially unrelated, and their

Predictive features of CT for risk stratifications in patients with primary gastrointestinal stromal tumour

International Nuclear Information System (INIS)

Zhou, Cuiping; Zhang, Xiang; Duan, Xiaohui; Hu, Huijun; Wang, Dongye; Shen, Jun

2016-01-01

To determine the predictive CT imaging features for risk stratifications in patients with primary gastrointestinal stromal tumours (GISTs). One hundred and twenty-nine patients with histologically confirmed primary GISTs (diameter >2 cm) were enrolled. CT imaging features were reviewed. Tumour risk stratifications were determined according to the 2008 NIH criteria where GISTs were classified into four categories according to the tumour size, location, mitosis count, and tumour rupture. The association between risk stratifications and CT features was analyzed using univariate analysis, followed by multinomial logistic regression and receiver operating characteristic (ROC) curve analysis. CT imaging features including tumour margin, size, shape, tumour growth pattern, direct organ invasion, necrosis, enlarged vessels feeding or draining the mass (EVFDM), lymphadenopathy, and contrast enhancement pattern were associated with the risk stratifications, as determined by univariate analysis (P < 0.05). Only lesion size, growth pattern and EVFDM remained independent risk factors in multinomial logistic regression analysis (OR = 3.480-100.384). ROC curve analysis showed that the area under curve of the obtained multinomial logistic regression model was 0.806 (95 % CI: 0.727-0.885). CT features including lesion size, tumour growth pattern, and EVFDM were predictors of the risk stratifications for GIST. (orig.)

Numerical analysis on hydrogen stratification and post-inerting of hydrogen risk

International Nuclear Information System (INIS)

Peng, Cheng; Tong, Lili; Cao, Xuewu

2016-01-01

Highlights: • A three-dimensional computational model was built and the applicability was discussed. • The formation of helium stratification was further studied. • Three influencing factors on the post-inerting of hydrogen risk were analyzed. - Abstract: In the case of severe accidents, the risk of hydrogen explosion threatens the integrity of the nuclear reactor containment. According to nuclear regulations, hydrogen control is required to ensure the safe operation of the nuclear reactor. In this study, the method of Computational Fluid Dynamics (CFD) has been applied to analyze process of hydrogen stratification and the post-inerting of hydrogen risk in the Large-Scale Gas Mixing Facility. A three-dimensional computational model was built and the applicability of different turbulence models was discussed. The result shows that the helium concentration calculated by the standard k–ε turbulence model is closest to the experiment data. Through analyzing the formation of helium stratification at different injection velocities, it is found that when the injection mass flow is constant and the injection velocity of helium increases, the mixture of helium and air is enhanced while there is rarely influence on the formation of helium stratification. In addition, the influences of mass flow rate, injection location and direction and inert gas on the post-inerting of hydrogen risk have been analyzed and the results are as follows: with the increasing of mass flow rate, the mitigation effect of nitrogen on hydrogen risk will be further improved; there is an obvious local difference between the mitigation effects of nitrogen on hydrogen risk in different injection directions and locations; when the inert gas is injected at the same mass flow rate, the mitigation effect of steam on hydrogen risk is better than that of nitrogen. This study can provide technical support for the mitigation of hydrogen risk in the small LWR containment.

A three-gene expression signature model for risk stratification of patients with neuroblastoma.

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Garcia, Idoia; Mayol, Gemma; Ríos, José; Domenech, Gema; Cheung, Nai-Kong V; Oberthuer, André; Fischer, Matthias; Maris, John M; Brodeur, Garrett M; Hero, Barbara; Rodríguez, Eva; Suñol, Mariona; Galvan, Patricia; de Torres, Carmen; Mora, Jaume; Lavarino, Cinzia

2012-04-01

Neuroblastoma is an embryonal tumor with contrasting clinical courses. Despite elaborate stratification strategies, precise clinical risk assessment still remains a challenge. The purpose of this study was to develop a PCR-based predictor model to improve clinical risk assessment of patients with neuroblastoma. The model was developed using real-time PCR gene expression data from 96 samples and tested on separate expression data sets obtained from real-time PCR and microarray studies comprising 362 patients. On the basis of our prior study of differentially expressed genes in favorable and unfavorable neuroblastoma subgroups, we identified three genes, CHD5, PAFAH1B1, and NME1, strongly associated with patient outcome. The expression pattern of these genes was used to develop a PCR-based single-score predictor model. The model discriminated patients into two groups with significantly different clinical outcome [set 1: 5-year overall survival (OS): 0.93 ± 0.03 vs. 0.53 ± 0.06, 5-year event-free survival (EFS): 0.85 ± 0.04 vs. 0.042 ± 0.06, both P model was an independent marker for survival (P model robustly classified patients in the total cohort and in different clinically relevant risk subgroups. We propose for the first time in neuroblastoma, a technically simple PCR-based predictor model that could help refine current risk stratification systems. ©2012 AACR.

Improving Clinical Risk Stratification at Diagnosis in Primary Prostate Cancer: A Prognostic Modelling Study.

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Vincent J Gnanapragasam

2016-08-01

Full Text Available Over 80% of the nearly 1 million men diagnosed with prostate cancer annually worldwide present with localised or locally advanced non-metastatic disease. Risk stratification is the cornerstone for clinical decision making and treatment selection for these men. The most widely applied stratification systems use presenting prostate-specific antigen (PSA concentration, biopsy Gleason grade, and clinical stage to classify patients as low, intermediate, or high risk. There is, however, significant heterogeneity in outcomes within these standard groupings. The International Society of Urological Pathology (ISUP has recently adopted a prognosis-based pathological classification that has yet to be included within a risk stratification system. Here we developed and tested a new stratification system based on the number of individual risk factors and incorporating the new ISUP prognostic score.Diagnostic clinicopathological data from 10,139 men with non-metastatic prostate cancer were available for this study from the Public Health England National Cancer Registration Service Eastern Office. This cohort was divided into a training set (n = 6,026; 1,557 total deaths, with 462 from prostate cancer and a testing set (n = 4,113; 1,053 total deaths, with 327 from prostate cancer. The median follow-up was 6.9 y, and the primary outcome measure was prostate-cancer-specific mortality (PCSM. An external validation cohort (n = 1,706 was also used. Patients were first categorised as low, intermediate, or high risk using the current three-stratum stratification system endorsed by the National Institute for Health and Care Excellence (NICE guidelines. The variables used to define the groups (PSA concentration, Gleason grading, and clinical stage were then used to sub-stratify within each risk category by testing the individual and then combined number of risk factors. In addition, we incorporated the new ISUP prognostic score as a discriminator. Using this approach, a

Arrhythmogenic Right Ventricular Cardiomyopathy: Risk Stratification and Indications for Defibrillator Therapy.

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Zorzi, Alessandro; Rigato, Ilaria; Bauce, Barbara; Pilichou, Kalliopi; Basso, Cristina; Thiene, Gaetano; Iliceto, Sabino; Corrado, Domenico

2016-06-01

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetically determined disease which predisposes to life-threatening ventricular arrhythmias. The main goal of ARVC therapy is prevention of sudden cardiac death (SCD). Implantable cardioverter defibrillator (ICD) is the most effective therapy for interruption of potentially lethal ventricular tachyarrhythmias. Despite its life-saving potential, ICD implantation is associated with a high rate of complications and significant impact on quality of life. Accurate risk stratification is needed to identify individuals who most benefit from the therapy. While there is general agreement that patients with a history of cardiac arrest or hemodynamically unstable ventricular tachycardia are at high risk of SCD and needs an ICD, indications for primary prevention remain a matter of debate. The article reviews the available scientific evidence and guidelines that may help to stratify the arrhythmic risk of ARVC patients and guide ICD implantation. Other therapeutic strategies, either alternative or additional to ICD, will be also addressed.

Degree of Agreement between Cardiovascular Risk Stratification Tools.

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Garcia, Guilherme Thomé; Stamm, Ana Maria Nunes de Faria; Rosa, Ariel Córdova; Marasciulo, Antônio Carlos; Marasciulo, Rodrigo Conill; Battistella, Cristian; Remor, Alexandre Augusto de Costa

2017-05-01

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in Brazil, and primary prevention care may be guided by risk stratification tools. The Framingham (FRS) and QRISK-2 (QRS) risk scores estimate 10-year overall cardiovascular risk in asymptomatic individuals, but the instrument of choice may lead to different therapeutic strategies. To evaluate the degree of agreement between FRS and QRS in 10-year overall cardiovascular risk stratification in disease-free individuals. Cross-sectional, observational, descriptive and analytical study in a convenience sample of 74 individuals attending the outpatient care service of a university hospital in Brazil between January 2014 and January 2015. After application of FRS and QRS, patients were classified in low/moderate risk (Brasil, e a prevenção primária pode ser direcionada com ferramentas que estratificam o risco. Os escores de Framingham (ERF) e QRISK-2 (ERQ) estimam o risco cardiovascular (RCV) global em 10 anos em indivíduos assintomáticos, mas a escolha do instrumento pode implicar em terapêuticas distintas. Observar o grau de concordância entre o ERF e o ERQ, na estratificação do risco cardiovascular global em 10 anos, nos indivíduos livres da doença. Estudo transversal, observacional, descritivo e analítico, com uma amostra de conveniência de 74 indivíduos, atendidos em um ambulatório de ensino de um hospital universitário brasileiro, no sul do país, de janeiro de 2014 a janeiro de 2015. O ERF e o ERQ foram aplicados nos pacientes, que foram classificados em baixo/moderado (superior no ERF que no ERQ (33,7% vs 21,6%), sendo identificado efeito sinérgico do gênero masculino com hipertensão arterial sistêmica nas duas ferramentas, e com faixa etária geriátrica no ERQ (p < 0,05) nesse estrato de risco. O índice de concordância Kappa entre os dois escores foi igual a 0,519 (IC95% = 0,386-0,652; p < 0,001). Houve concordância moderada entre o ERF e o ERQ, na estimativa de

Segmented Poincaré plot analysis for risk stratification in patients with dilated cardiomyopathy.

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Voss, A; Fischer, C; Schroeder, R; Figulla, H R; Goernig, M

2010-01-01

The prognostic value of heart rate variability in patients with dilated cardiomyopathy (DCM) is limited and does not contribute to risk stratification although the dynamics of ventricular repolarization differs considerably between DCM patients and healthy subjects. Neither linear nor nonlinear methods of heart rate variability analysis could discriminate between patients at high and low risk for sudden cardiac death. The aim of this study was to analyze the suitability of the new developed segmented Poincaré plot analysis (SPPA) to enhance risk stratification in DCM. In contrast to the usual applied Poincaré plot analysis the SPPA retains nonlinear features from investigated beat-to-beat interval time series. Main features of SPPA are the rotation of cloud of points and their succeeded variability depended segmentation. Significant row and column probabilities were calculated from the segments and led to discrimination (up to pplot analysis of heart rate variability was able to contribute to risk stratification in patients suffering from DCM.

Developing a PTEN-ERG Signature to Improve Molecular Risk Stratification in Prostate Cancer

Science.gov (United States)

2017-10-01

AWARD NUMBER: W81XWH-16-1-0737 TITLE: Developing a PTEN-ERG Signature to Improve Molecular Risk Stratification in Prostate Cancer PRINCIPAL...AND SUBTITLE 5a. CONTRACT NUMBER Developing a PTEN-ERG Signature to Improve Molecular Risk Stratification in Prostate Cancer 5b. GRANT NUMBER W81XWH...that there exist distinctive molecular correlates of PTEN loss in the context of ETS-negative versus ETS-positive human prostate cancers and that

Comparing an Unstructured Risk Stratification to Published Guidelines in Acute Coronary Syndromes.

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Beck, Ann-Jean C C; Hagemeijer, Anouk; Tortolani, Bess; Byrd, Bethany A; Parekh, Amisha; Datillo, Paris; Birkhahn, Robert

2015-09-01

Guidelines are designed to encompass the needs of the majority of patients with a particular condition. The American Heart Association (AHA) in conjunction with the American College of Cardiology (ACC) and the American College of Emergency Physicians (ACEP) developed risk stratification guidelines to aid physicians with accurate and efficient diagnosis and management of patients with acute coronary syndrome (ACS). While useful in a primary care setting, in the unique environment of an emergency department (ED), the feasibility of incorporating guidelines into clinical workflow remains in question. We aim to compare emergency physicians' (EP) clinical risk stratification ability to AHA/ACC/ACEP guidelines for ACS, and assessed each for accuracy in predicting ACS. We conducted a prospective observational cohort study in an urban teaching hospital ED. All patients presenting to the ED with chest pain who were evaluated for ACS had two risk stratification scores assigned: one by the treating physician based on clinical evaluation and the other by the AHA/ACC/ACEP guideline aforementioned. The patient's ACS risk stratification classified by the EP was compared to AHA/ACC/ACEP guidelines. Patients were contacted at 30 days following the index ED visit to determine all cause mortality, unscheduled hospital/ED revisits, and objective cardiac testing performed. We enrolled 641 patients presenting for evaluation by 21 different EPs. There was a difference between the physician's clinical assessment used in the ED, and the AHA/ACC/ACEP task force guidelines. EPs were more likely to assess patients as low risk (40%), while AHA/ACC/ACEP guidelines were more likely to classify patients as intermediate (45%) or high (45%) risk. Of the 119 (19%) patients deemed high risk by EP evaluation, 38 (32%) were diagnosed with ACS. AHA/ACC/ACEP guidelines classified only 57 (9%) patients low risk with 56 (98%) of those patients diagnosed with no ACS. In the ED, physicians are more efficient

Noninvasive risk stratification of lethal ventricular arrhythmias and sudden cardiac death after myocardial infarction

Directory of Open Access Journals (Sweden)

Kenji Yodogawa, MD

2014-08-01

Full Text Available Prediction of lethal ventricular arrhythmias leading to sudden cardiac death is one of the most important and challenging problems after myocardial infarction (MI. Identification of MI patients who are prone to ventricular tachyarrhythmias allows for an indication of implantable cardioverter-defibrillator placement. To date, noninvasive techniques such as microvolt T-wave alternans (MTWA, signal-averaged electrocardiography (SAECG, heart rate variability (HRV, and heart rate turbulence (HRT have been developed for this purpose. MTWA is an indicator of repolarization abnormality and is currently the most promising risk-stratification tool for predicting malignant ventricular arrhythmias. Similarly, late potentials detected by SAECG are indices of depolarization abnormality and are useful in risk stratification. However, the role of SAECG is limited because of its low predictive accuracy. Abnormal HRV and HRT patterns reflect autonomic disturbances, which may increase the risk of lethal ventricular arrhythmias, but the existing evidence is insufficient. Further studies of noninvasive assessment may provide a new insight into risk stratification in post-MI patients.

Risk stratification in secondary cardiovascular prevention.

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Lazzeroni, Davide; Coruzzi, Paolo

2018-02-19

Worldwide, more than 7 million people experience acute myocardial infarction (AMI) every year (1), and although substantial reduction in mortality has been obtained in recent decades, one-year mortality rates are still in the range of 10%. Among patients who survive AMI, 20% suffer a second cardiovascular event in the first year and approximately 50% of major coronary events occur in those with a previous hospital discharge diagnosis of AMI (2). Despite the evidence that lifestyle changes and risk factors management strongly improve long-term prognosis, preventive care post-AMI remains sub-optimal. Cross-sectional data from the serially conducted EUROASPIRE surveys in patients with established ischemic heart disease (IHD) and people at high cardiovascular risk have demonstrated a high prevalence of unhealthy lifestyle, modifiable risk factors and inadequate use of drug therapies to achieve blood pressure and lipid goals (3). Secondary prevention programmes, defined as the level of preventive care focusing on early risk stratification, are highly recommended in all IHD patients, to restore quality of life, maintain or improve functional capacity and prevent recurrence.

Risk Stratification and Shared Decision Making for Colorectal Cancer Screening: A Randomized Controlled Trial.

Science.gov (United States)

Schroy, Paul C; Duhovic, Emir; Chen, Clara A; Heeren, Timothy C; Lopez, William; Apodaca, Danielle L; Wong, John B

2016-05-01

Eliciting patient preferences within the context of shared decision making has been advocated for colorectal cancer (CRC) screening, yet providers often fail to comply with patient preferences that differ from their own. To determine whether risk stratification for advanced colorectal neoplasia (ACN) influences provider willingness to comply with patient preferences when selecting a desired CRC screening option. Randomized controlled trial. Asymptomatic, average-risk patients due for CRC screening in an urban safety net health care setting. Patients were randomized 1:1 to a decision aid alone (n= 168) or decision aid plus risk assessment (n= 173) arm between September 2012 and September 2014. The primary outcome was concordance between patient preference and test ordered; secondary outcomes included patient satisfaction with the decision-making process, screening intentions, test completion rates, and provider satisfaction. Although providers perceived risk stratification to be useful in selecting an appropriate screening test for their average-risk patients, no significant differences in concordance were observed between the decision aid alone and decision aid plus risk assessment groups (88.1% v. 85.0%,P= 0.40) or high- and low-risk groups (84.5% v. 87.1%,P= 0.51). Concordance was highest for colonoscopy and relatively low for tests other than colonoscopy, regardless of study arm or risk group. Failure to comply with patient preferences was negatively associated with satisfaction with the decision-making process, screening intentions, and test completion rates. Single-institution setting; lack of provider education about the utility of risk stratification into their decision making. Providers perceived risk stratification to be useful in their decision making but often failed to comply with patient preferences for tests other than colonoscopy, even among those deemed to be at low risk of ACN. © The Author(s) 2016.

Noninvasive risk stratification for sudden death in asymptomatic patients with Wolff-Parkinson-White syndrome.

Science.gov (United States)

Novella, John; DeBiasi, Ralph M; Coplan, Neil L; Suri, Ranji; Keller, Seth

2014-01-01

Sudden cardiac death (SCD) as the first clinical manifestation of Wolff-Parkinson-White (WPW) syndrome is a well-documented, although rare occurrence. The incidence of SCD in patients with WPW ranges from 0% to 0.39% annually. Controversy exists regarding risk stratification for patients with preexcitation on surface electrocardiogram (ECG), particularly in those who are asymptomatic. This article focuses on the role of risk stratification using exercise and pharmacologic testing in patients with WPW pattern on ECG.

Clinical Studies in Risk Stratification & Therapy of Thoracic Aortic Disease

NARCIS (Netherlands)

Kamman, AV

2017-01-01

For this thesis we aimed to summarize outcomes and optimal treatment modality for thoracic aortic disease, discuss new imaging techniques and improve the use of current imaging modalities. Furthermore, we aimed to improve risk stratification for uncomplicated type B aortic dissection (TBAD) and

Short-term versus long-term heart rate variability in ischemic cardiomyopathy risk stratification

Directory of Open Access Journals (Sweden)

Andreas eVoss

2013-12-01

Full Text Available In industrialized countries with aging populations, heart failure affects 0.3%-2% of the general population. The investigation of 24h-ECG recordings revealed the potential of nonlinear indices of heart rate variability (HRV for enhanced risk stratification in patients with ischemic heart failure (IHF. However, long-term analyses are time-consuming, expensive and delay the initial diagnosis. The objective of this study was to investigate whether 30min short-term HRV analysis is sufficient for comparable risk stratification in IHF in comparison to 24h-HRV analysis. From 256 IHF patients (221 at low risk (IHFLR and 35 at high risk (IHFHR a 24h beat-to-beat time series b the first 30min segment c the 30min most stationary day segment and d the 30min most stationary night segment were investigated. We calculated linear (time and frequency domain and nonlinear HRV analysis indices. Optimal parameter sets for risk stratification in IHF were determined for 24 hours and for each 30min segment by applying discriminant analysis on significant clinical and non-clinical indices. Long- and short-term HRV indices from frequency domain and particularly from nonlinear dynamics revealed high univariate significances (p

Utility of the exercise electrocardiogram testing in sudden cardiac death risk stratification.

Science.gov (United States)

Refaat, Marwan M; Hotait, Mostafa; Tseng, Zian H

2014-07-01

Sudden cardiac death (SCD) remains a major public health problem. Current established criteria identifying those at risk of sudden arrhythmic death, and likely to benefit from implantable cardioverter defibrillators (ICDs), are neither sensitive nor specific. Exercise electrocardiogram (ECG) testing was traditionally used for information concerning patients' symptoms, exercise capacity, cardiovascular function, myocardial ischemia detection, and hemodynamic responses during activity in patients with hypertrophic cardiomyopathy. We conducted a systematic review of MEDLINE on the utility of exercise ECG testing in SCD risk stratification. Exercise testing can unmask suspected primary electrical diseases in certain patients (catecholaminergic polymorphic ventricular tachycardia or concealed long QT syndrome) and can be effectively utilized to risk stratify patients at an increased (such as early repolarization syndrome and Brugada syndrome) or decreased risk of SCD, such as the loss of preexcitation on exercise testing in asymptomatic Wolff-Parkinson-White syndrome. Exercise ECG testing helps in SCD risk stratification in patients with and without arrhythmogenic hereditary syndromes. © 2014 Wiley Periodicals, Inc.

Cost-Effectiveness Analysis: Risk Stratification of Nonalcoholic Fatty Liver Disease (NAFLD by the Primary Care Physician Using the NAFLD Fibrosis Score.

Directory of Open Access Journals (Sweden)

Elliot B Tapper

Full Text Available The complications of Nonalcoholic Fatty Liver Disease (NAFLD are dependent on the presence of advanced fibrosis. Given the high prevalence of NAFLD in the US, the optimal evaluation of NAFLD likely involves triage by a primary care physician (PCP with advanced disease managed by gastroenterologists.We compared the cost-effectiveness of fibrosis risk-assessment strategies in a cohort of 10,000 simulated American patients with NAFLD performed in either PCP or referral clinics using a decision analytical microsimulation state-transition model. The strategies included use of vibration-controlled transient elastography (VCTE, the NAFLD fibrosis score (NFS, combination testing with NFS and VCTE, and liver biopsy (usual care by a specialist only. NFS and VCTE performance was obtained from a prospective cohort of 164 patients with NAFLD. Outcomes included cost per quality adjusted life year (QALY and correct classification of fibrosis.Risk-stratification by the PCP using the NFS alone costs $5,985 per QALY while usual care costs $7,229/QALY. In the microsimulation, at a willingness-to-pay threshold of $100,000, the NFS alone in PCP clinic was the most cost-effective strategy in 94.2% of samples, followed by combination NFS/VCTE in the PCP clinic (5.6% and usual care in 0.2%. The NFS based strategies yield the best biopsy-correct classification ratios (3.5 while the NFS/VCTE and usual care strategies yield more correct-classifications of advanced fibrosis at the cost of 3 and 37 additional biopsies per classification.Risk-stratification of patients with NAFLD primary care clinic is a cost-effective strategy that should be formally explored in clinical practice.

The Auckland Cataract Study: Assessing Preoperative Risk Stratification Systems for Phacoemulsification Surgery in a Teaching Hospital.

Science.gov (United States)

Kim, Bia Z; Patel, Dipika V; Sherwin, Trevor; McGhee, Charles N J

2016-11-01

To evaluate 2 preoperative risk stratification systems for assessing the risk of complications in phacoemulsification cataract surgery, performed by residents, fellows, and attending physicians in a public teaching hospital. Cohort study. One observer assessed the clinical data of 500 consecutive cases, prior to phacoemulsification cataract surgery performed between April and June 2015 at Greenlane Clinical Centre, Auckland, New Zealand. Preoperatively 2 risk scores were calculated for each case using the Muhtaseb and Buckinghamshire risk stratification systems. Complications, intraoperative and postoperative, and visual outcomes were analyzed in relation to these risk scores. Intraoperative complication rates increased with higher risk scores using the Muhtaseb or Buckinghamshire stratification system (P = .001 and P = .003, respectively, n = 500). The odds ratios for residents and fellows were not significantly different from attending physicians after case-mix adjustment according to risk scores (P > .05). Postoperative complication rates increased with higher Buckinghamshire risk scores but not with Muhtaseb scores (P = .014 and P = .094, respectively, n = 476). Postoperative corrected-distance visual acuity was poorer with higher risk scores (P < .001 for both, n = 476). This study confirms that the risk of intraoperative complications increases with higher preoperative risk scores. Furthermore, higher risk scores correlate with poorer postoperative visual acuity and the Buckinghamshire risk score also correlates with postoperative complications. Therefore, preoperative assessment using such risk stratification systems could assist individual informed consent, preoperative surgical planning, safe allocation of cases to trainees, and more meaningful analyses of outcomes for individual surgeons and institutions. Copyright © 2016 Elsevier Inc. All rights reserved.

Unification of favourable intermediate-, unfavourable intermediate-, and very high-risk stratification criteria for prostate cancer.

Science.gov (United States)

Zumsteg, Zachary S; Zelefsky, Michael J; Woo, Kaitlin M; Spratt, Daniel E; Kollmeier, Marisa A; McBride, Sean; Pei, Xin; Sandler, Howard M; Zhang, Zhigang

2017-11-01

To improve on the existing risk-stratification systems for prostate cancer. This was a retrospective investigation including 2 248 patients undergoing dose-escalated external beam radiotherapy (EBRT) at a single institution. We separated National Comprehensive Cancer Network (NCCN) intermediate-risk prostate cancer into 'favourable' and 'unfavourable' groups based on primary Gleason pattern, percentage of positive biopsy cores (PPBC), and number of NCCN intermediate-risk factors. Similarly, NCCN high-risk prostate cancer was stratified into 'standard' and 'very high-risk' groups based on primary Gleason pattern, PPBC, number of NCCN high-risk factors, and stage T3b-T4 disease. Patients with unfavourable-intermediate-risk (UIR) prostate cancer had significantly inferior prostate-specific antigen relapse-free survival (PSA-RFS, P prostate cancer-specific mortality (PCSM, P prostate cancer. Similarly, patients with very high-risk (VHR) prostate cancer had significantly worse PSA-RFS (P prostate cancer. Moreover, patients with FIR and low-risk prostate cancer had similar outcomes, as did patients with UIR and SHR prostate cancer. Consequently, we propose the following risk-stratification system: Group 1, low risk and FIR; Group 2, UIR and SHR; and Group 3, VHR. These groups have markedly different outcomes, with 8-year distant metastasis rates of 3%, 9%, and 29% (P < 0.001) for Groups 1, 2, and 3, respectively, and 8-year PCSM of 1%, 4%, and 13% (P < 0.001) after EBRT. This modified stratification system was significantly more accurate than the three-tiered NCCN system currently in clinical use for all outcomes. Modifying the NCCN risk-stratification system to group FIR with low-risk patients and UIR with SHR patients, results in modestly improved prediction of outcomes, potentially allowing better personalisation of therapeutic recommendations. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

Characteristic and Preferences of Green Consumer Stratification As Bases to Formulating Marketing Strategies of Ecolabel-Certified Furniture

Directory of Open Access Journals (Sweden)

Ririn Wulandari

2012-06-01

question. The components used were: satisfaction, safety, socialization, and sustainability, as well as government policies which could open markets. The respondents were 408 potential consumers in Jakarta and its surroundings. The method used was purposive and convenience sampling, in which the survey was conducted at exhibitions and showrooms. Ward Method, Stepwise Discriminant Analysis and Biplot Analysis were used to generate consumer stratifications. Before that, reliability tests were conducted using Crombach Alpha method. In addition, data was explored and reduced using Component Principle Analysis. Preference analysis was performed using the method proposed by Thurston Case V. This study results four stratifications of green consumers. There were similarities and differences in preference on each of the stratification of the component of green marketing strategy as well as the marketing strategies of furniture-certified ecolabel for the targeted consumers.

Risk stratification of thyroid nodules on ultrasonography with the French TI-RADS: Description and reflections

International Nuclear Information System (INIS)

Russ, Gilles

2016-01-01

The widespread use of ultrasonography places it in a key position for use in the risk stratification of thyroid nodules. The French proposal is a five-tier system, our version of a thyroid imaging reporting and database system (TI-RADS), which includes a standardized vocabulary and report and a quantified risk assessment. It allows the selection of the nodules that should be referred for fine-needle aspiration biopsies. Effort should be directed towards merging the different risk stratification systems utilized around the world and testing this unified system with multi-center studies

Risk stratification of thyroid nodules on ultrasonography with the French TI-RADS: Description and reflections

Energy Technology Data Exchange (ETDEWEB)

Russ, Gilles [Thyroid and Endocrine Tumor Unit, Department of Nuclear Medicine, La Pitie Salpetriere Hospital, Pierre and Marie Curie University, Paris (Korea, Republic of)

2016-01-15

The widespread use of ultrasonography places it in a key position for use in the risk stratification of thyroid nodules. The French proposal is a five-tier system, our version of a thyroid imaging reporting and database system (TI-RADS), which includes a standardized vocabulary and report and a quantified risk assessment. It allows the selection of the nodules that should be referred for fine-needle aspiration biopsies. Effort should be directed towards merging the different risk stratification systems utilized around the world and testing this unified system with multi-center studies.

Electrophysiologic profile and results of invasive risk stratification in asymptomatic children and adolescents with the Wolff-Parkinson-White electrocardiographic pattern.

Science.gov (United States)

Kubuš, Peter; Vít, Pavel; Gebauer, Roman A; Materna, Ondřej; Janoušek, Jan

2014-04-01

Data on the results and clinical effect of an invasive risk stratification strategy in asymptomatic young patients with the Wolff-Parkinson-White electrocardiographic pattern are scarce. Eighty-five consecutive patients agedWolff-Parkinson-White pattern and persistent preexcitation at maximum exercise undergoing invasive risk stratification were retrospectively studied. Adverse accessory pathway (AP) properties were defined according to currently consented criteria as any of the following: shortest preexcited RR interval during atrial fibrillation/rapid atrial pacing≤250 ms (or antegrade effective refractory period≤250 ms if shortest preexcited RR interval was not available) or inducible atrioventricular re-entrant tachycardia. Age at evaluation was median 14.9 years. Eighty-two patients had a structurally normal heart and 3 had hypertrophic cardiomyopathy. A single manifest AP was present in 80, 1 manifest and 1 concealed AP in 4, and 2 manifest APs in 1 patient. Adverse AP properties were present in 32 of 85 patients (37.6%) at baseline and in additional 16 of 44 (36.4%) after isoproterenol. Ablation was performed in 41 of these 48 patients. Ablation was deferred in the remaining 7 for pathway proximity to the atrioventricular node. In addition, 18 of the low-risk patients were ablated based on patient/parental decision. Adverse AP properties at baseline were exhibited by 37.6% of the evaluated patients with an asymptomatic Wolff-Parkinson-White preexcitation persisting at peak exercise. Isoproterenol challenge yielded additional 36.4% of those tested at higher risk. Ablation was performed in a total of 69.4% of patients subjected to invasive risk stratification.

What imaging techniques should be used in primary versus secondary prevention for further risk stratification?

Science.gov (United States)

Schiele, François; Navarese, Eliano Pio; Visoná, Adriana; Ray, Kausik

2017-04-01

An accurate assessment of the cardiovascular (CV) risk of an individual is key for guiding the appropriate treatment strategy for cardiovascular disease (CVD). Although conventional risk factors for CVD are well established, there can be substantial variation in the extent of atherosclerosis between patients. The use of a variety of imaging modalities can be beneficial in the primary prevention stage and in the classification of an individual's CV risk. Therefore, appropriate implementation of these imaging techniques for risk assessment purposes, in line with clinical guidelines, can influence the outcomes of CVD prevention. The expert working group collaborated to review current invasive and non-invasive imaging techniques available to healthcare practitioners and how they can be used in the measurement of preclinical vascular damage and CV risk assessment. After evaluation of the current guideline recommendations and clinical data available, the expert working group collaborated to produce recommendations regarding the use of imaging in the risk stratification in primary prevention, CV risk in peri-acute coronary syndrome and CV risk assessment in secondary prevention. Overall, a variety of both invasive and non-invasive imaging modalities were highlighted by the expert working group as having the potential to assist in the risk assessments of patients at risk of CVD. These imaging techniques can be utilised in both primary and secondary prevention strategies and have the potential to be important risk modifiers, improving the outcome of CV risk assessment. Copyright © 2017 Elsevier B.V. All rights reserved.

205_WS: Improving the Delivery of Primary Care Through Risk Stratification

DEFF Research Database (Denmark)

Kinder, Karen; Kristensen, Troels; Abrams, Chad

. Content The workshop will open with an introductory presentation on the numerous applications of risk stratification within the integrated and primary care sectors. The workshop will then focus on individual sessions based on three applications: – Case Management. – Improving Coordination...

Validating a Local Failure Risk Stratification for Use in Prospective Studies of Adjuvant Radiation Therapy for Bladder Cancer

International Nuclear Information System (INIS)

Baumann, Brian C.; He, Jiwei; Hwang, Wei-Ting; Tucker, Kai N.; Bekelman, Justin E.; Herr, Harry W.; Lerner, Seth P.; Guzzo, Thomas J.; Malkowicz, S. Bruce; Christodouleas, John P.

2016-01-01

Purpose: To inform prospective trials of adjuvant radiation therapy (adj-RT) for bladder cancer after radical cystectomy, a locoregional failure (LF) risk stratification was proposed. This stratification was developed and validated using surgical databases that may not reflect the outcomes expected in prospective trials. Our purpose was to assess sources of bias that may affect the stratification model's validity or alter the LF risk estimates for each subgroup: time bias due to evolving surgical techniques; trial accrual bias due to inclusion of patients who would be ineligible for adj-RT trials because of early disease progression, death, or loss to follow-up shortly after cystectomy; bias due to different statistical methods to estimate LF; and subgrouping bias due to different definitions of the LF subgroups. Methods and Materials: The LF risk stratification was developed using a single-institution cohort (n=442, 1990-2008) and the multi-institutional SWOG 8710 cohort (n=264, 1987-1998) treated with radical cystectomy with or without chemotherapy. We evaluated the sensitivity of the stratification to sources of bias using Fine-Gray regression and Kaplan-Meier analyses. Results: Year of radical cystectomy was not associated with LF risk on univariate or multivariate analysis after controlling for risk group. By use of more stringent inclusion criteria, 26 SWOG patients (10%) and 60 patients from the single-institution cohort (14%) were excluded. Analysis of the remaining patients confirmed 3 subgroups with significantly different LF risks with 3-year rates of 7%, 17%, and 36%, respectively (P<.01), nearly identical to the rates without correcting for trial accrual bias. Kaplan-Meier techniques estimated higher subgroup LF rates than competing risk analysis. The subgroup definitions used in the NRG-GU001 adj-RT trial were validated. Conclusions: These sources of bias did not invalidate the LF risk stratification or substantially change the model's LF estimates.

Preventing tomorrow's sudden cardiac death today: part I: Current data on risk stratification for sudden cardiac death.

Science.gov (United States)

Al-Khatib, Sana M; Sanders, Gillian D; Bigger, J Thomas; Buxton, Alfred E; Califf, Robert M; Carlson, Mark; Curtis, Anne; Curtis, Jeptha; Fain, Eric; Gersh, Bernard J; Gold, Michael R; Haghighi-Mood, Ali; Hammill, Stephen C; Healey, Jeff; Hlatky, Mark; Hohnloser, Stefan; Kim, Raymond J; Lee, Kerry; Mark, Daniel; Mianulli, Marcus; Mitchell, Brent; Prystowsky, Eric N; Smith, Joseph; Steinhaus, David; Zareba, Wojciech

2007-06-01

Accurate and timely prediction of sudden cardiac death (SCD) is a necessary prerequisite for effective prevention and therapy. Although the largest number of SCD events occurs in patients without overt heart disease, there are currently no tests that are of proven predictive value in this population. Efforts in risk stratification for SCD have focused primarily on predicting SCD in patients with known structural heart disease. Despite the ubiquity of tests that have been purported to predict SCD vulnerability in such patients, there is little consensus on which test, in addition to the left ventricular ejection fraction, should be used to determine which patients will benefit from an implantable cardioverter defibrillator. On July 20 and 21, 2006, a group of experts representing clinical cardiology, cardiac electrophysiology, biostatistics, economics, and health policy were joined by representatives of the US Food and Drug administration, Centers for Medicare Services, Agency for Health Research and Quality, the Heart Rhythm Society, and the device and pharmaceutical industry for a round table meeting to review current data on strategies of risk stratification for SCD, to explore methods to translate these strategies into practice and policy, and to identify areas that need to be addressed by future research studies. The meeting was organized by the Duke Center for the Prevention of SCD at the Duke Clinical Research Institute and was funded by industry participants. This article summarizes the presentations and discussions that occurred at that meeting.

Correction of population stratification in large multi-ethnic association studies.

Directory of Open Access Journals (Sweden)

David Serre

2008-01-01

Full Text Available The vast majority of genetic risk factors for complex diseases have, taken individually, a small effect on the end phenotype. Population-based association studies therefore need very large sample sizes to detect significant differences between affected and non-affected individuals. Including thousands of affected individuals in a study requires recruitment in numerous centers, possibly from different geographic regions. Unfortunately such a recruitment strategy is likely to complicate the study design and to generate concerns regarding population stratification.We analyzed 9,751 individuals representing three main ethnic groups - Europeans, Arabs and South Asians - that had been enrolled from 154 centers involving 52 countries for a global case/control study of acute myocardial infarction. All individuals were genotyped at 103 candidate genes using 1,536 SNPs selected with a tagging strategy that captures most of the genetic diversity in different populations. We show that relying solely on self-reported ethnicity is not sufficient to exclude population stratification and we present additional methods to identify and correct for stratification.Our results highlight the importance of carefully addressing population stratification and of carefully "cleaning" the sample prior to analyses to obtain stronger signals of association and to avoid spurious results.

Prodromal Parkinsonism and Neurodegenerative Risk Stratification in REM Sleep Behavior Disorder.

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Barber, Thomas R; Lawton, Michael; Rolinski, Michal; Evetts, Samuel; Baig, Fahd; Ruffmann, Claudio; Gornall, Aimie; Klein, Johannes C; Lo, Christine; Dennis, Gary; Bandmann, Oliver; Quinnell, Timothy; Zaiwalla, Zenobia; Ben-Shlomo, Yoav; Hu, Michele T M

2017-08-01

Rapid eye movement (REM) sleep behavior disorder (RBD) is the most specific marker of prodromal alpha-synucleinopathies. We sought to delineate the baseline clinical characteristics of RBD and evaluate risk stratification models. Clinical assessments were performed in 171 RBD, 296 control, and 119 untreated Parkinson's (PD) participants. Putative risk measures were assessed as predictors of prodromal neurodegeneration, and Movement Disorders Society (MDS) criteria for prodromal PD were applied. Participants were screened for common leucine-rich repeat kinase 2 (LRRK2)/glucocerebrosidase gene (GBA) gene mutations. Compared to controls, participants with RBD had higher rates of solvent exposure, head injury, smoking, obesity, and antidepressant use. GBA mutations were more common in RBD, but no LRRK2 mutations were found. RBD participants performed significantly worse than controls on Unified Parkinson's Disease Rating Scale (UPDRS)-III, timed "get-up-and-go", Flamingo test, Sniffin Sticks, and cognitive tests and had worse measures of constipation, quality of life (QOL), and orthostatic hypotension. For all these measures except UPDRS-III, RBD and PD participants were equally impaired. Depression, anxiety, and apathy were worse in RBD compared to PD participants. Stratification of people with RBD according to antidepressant use, obesity, and age altered the odds ratio (OR) of hyposmia compared to controls from 3.4 to 45.5. 74% (95% confidence interval [CI] 66%, 80%) of RBD participants met the MDS criteria for probable prodromal Parkinson's compared to 0.3% (95% CI 0.009%, 2%) of controls. RBD are impaired across a range of clinical measures consistent with prodromal PD and suggestive of a more severe nonmotor subtype. Clinical risk stratification has the potential to select higher risk patients for neuroprotective interventions. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].

[Sports medical aspects in cardiac risk stratification--heart rate variability and exercise capacity].

Science.gov (United States)

Banzer, W; Lucki, K; Bürklein, M; Rosenhagen, A; Vogt, L

2006-12-01

The present study investigates the association of the predicted CHD-risk (PROCAM) with the individual endurance capacity and heart rate variability (HRV) in a population-based sample of sedentary elderly. After stratification, in 57 men (48.1+/-9.5 yrs.) with an overall PROCAM-risk or =10% (50.8+/-5.6 points) cycle ergometries and short-term HRV analysis of time (RRMEAN, SDNN, RMSSD) and frequency domain parameters (LF, HF, TP, LF/HF) were conducted. Additionally the autonomic stress index (SI) was calculated. Nonparametric tests were used for statistical correlation analysis (Spearman rho) and group comparisons (Mann-Whitney). For endurance capacity [W/kg] (r=-0.469, pHRV analysis in risk stratification and outline the interrelation of a decreased exercise capacity and autonomic function with a raised individual 10-year cardiac risk. As an independent parameter of the vegetative regulatory state the stress index may contribute to an increased practical relevance of short-time HRV analysis.

Clinical outcome and risk stratification in Brugada syndrome

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Tadashi Wada, MD

2013-04-01

Full Text Available Since the first report on Brugada syndrome, various risk markers for the prediction of ventricular fibrillation (VF in patients with Brugada syndrome have been reported. Multicenter trials reported spontaneous type 1 electrocardiogram (ECG and disease symptoms as prognostic predictors. VF induction by programmed electrical stimulation is still controversial, and most of the studies have failed to prove its significance for the prediction of spontaneous VF episodes. In Japan, although most multicenter studies have shown that patients with type 1 ECG were at high risk, it is difficult to determine the indication for implantation of an implantable cardioverter defibrillator only based on the ECG type. Recent studies have added new risk markers, such as inferolateral early repolarization, fragmented QRS, and shorter effective refractory periods of the ventricle, in addition to type 1 ECG and symptoms. Here, we review the clinical outcome and indices reported as reliable prognostic factors of Brugada syndrome with a focus on the clinical and ECG markers for risk stratification.

Syncope: risk stratification and clinical decision making.

Science.gov (United States)

Peeters, Suzanne Y G; Hoek, Amber E; Mollink, Susan M; Huff, J Stephen

2014-04-01

Syncope is a common occurrence in the emergency department, accounting for approximately 1% to 3% of presentations. Syncope is best defined as a brief loss of consciousness and postural tone followed by spontaneous and complete recovery. The spectrum of etiologies ranges from benign to life threatening, and a structured approach to evaluating these patients is key to providing care that is thorough, yet cost-effective. This issue reviews the most relevant evidence for managing and risk stratifying the syncope patient, beginning with a focused history, physical examination, electrocardiogram, and tailored diagnostic testing. Several risk stratification decision rules are compared for performance in various scenarios, including how age and associated comorbidities may predict short-term and long-term adverse events. An algorithm for structured, evidence-based care of the syncope patient is included to ensure that patients requiring hospitalization are managed appropriately and those with benign causes are discharged safely.

[Comparison of the present and previously used protocol of risk stratification in children with acute lymphoblastic leukemia].

Science.gov (United States)

Glodkowska, Eliza; Bialas, Agnieszka; Jackowska, Teresa

2007-01-01

Acute lymphoblastic leukaemia (ALL) is one of the most common cancers in children. In Poland, since November 2002 a new protocol of risk stratification has been recommended for assessment of risk factors and for choosing therapy regimens. assessment of accuracy of protocol ALL-IC 2002 in comparison to previously used risk stratification protocols. ALL was diagnosed in 100 children (44 girls, 56 boys; 1-18 years of age) in the Department of Pediatric Hematology and Oncology, Warsaw Medical University, over the period from November 2002 to November 2006. According to the ALL-IC 2002 protocol the patients were divided into three risk groups: SR-standard, IR-intermediate and HR-high. The stratification was by age, leukocyte count, cytogenetic changes, early response to prednisone therapy and bone marrow remission. In the previously used risk stratification protocols-BFM-90, only hepatosplenomegaly and the number of blasts in peripheral blood (PB) were considered, and the patients were divided into three risk groups: low (LRG1.2). out of the 100 patients qualified for treatment regimens according to the ALL-IC 2002 protocol, 97 entered remission, 11 died and 3 had a relapse. Under the ALL-IC 2002 protocol these children were stratified into the following groups: SR-31%, IR-44% and HR-25%. In the previously used stratification, there would be 26% children in low, 46% in the medium and 28% in the high risk group. According to the BFM-90 protocol 18/31 (58%) and 16/44 (36%) patients from the SR and IR groups respectively would be given more intensive treatment. On the other hand 11/44 (25%) and 14/25 (56%) patients from the IR and HR groups respectively would be given less intensive treatment. 1. ALL-IC 2002 protocol in comparison with the previously used protocol BFM-90, changes the qualification of children with ALL for the SR, IR and HR risk groups. This is linked to basic change of treatment protocol, adequate to severity of disease. 2. Children with ALL qualified

Modified risk stratification grouping using standard clinical and biopsy information for patients undergoing radical prostatectomy: Results from SEARCH.

Science.gov (United States)

Zumsteg, Zachary S; Chen, Zinan; Howard, Lauren E; Amling, Christopher L; Aronson, William J; Cooperberg, Matthew R; Kane, Christopher J; Terris, Martha K; Spratt, Daniel E; Sandler, Howard M; Freedland, Stephen J

2017-12-01

Prostate cancer is a heterogeneous disease, and risk stratification systems have been proposed to guide treatment decisions. However, significant heterogeneity remains for those with unfavorable-risk disease. This study included 3335 patients undergoing radical prostatectomy without adjuvant radiotherapy in the SEARCH database. High-risk patients were dichotomized into standard and very high-risk (VHR) groups based on primary Gleason pattern, percentage of positive biopsy cores (PPBC), number of NCCN high-risk factors, and stage T3b-T4 disease. Similarly, intermediate-risk prostate cancer was separated into favorable and unfavorable groups based on primary Gleason pattern, PPBC, and number of NCCN intermediate-risk factors. Median follow-up was 78 months. Patients with VHR prostate cancer had significantly worse PSA relapse-free survival (PSA-RFS, P < 0.001), distant metastasis (DM, P = 0.004), and prostate cancer-specific mortality (PCSM, P = 0.015) in comparison to standard high-risk (SHR) patients in multivariable analyses. By contrast, there was no significant difference in PSA-RFS, DM, or PCSM between SHR and unfavorable intermediate-risk (UIR) patients. Therefore, we propose a novel risk stratification system: Group 1 (low-risk), Group 2 (favorable intermediate-risk), Group 3 (UIR and SHR), and Group 4 (VHR). The c-index of this new grouping was 0.683 for PSA-RFS and 0.800 for metastases, compared to NCCN-risk groups which yield 0.666 for PSA-RFS and 0.764 for metastases. Patients classified as VHR have markedly increased rates of PSA relapse, DM, and PCSM in comparison to SHR patients, whereas UIR and SHR patients have similar prognosis. Novel therapeutic strategies are needed for patients with VHR, likely involving multimodality therapy. © 2017 Wiley Periodicals, Inc.

Improving risk-stratification of Diabetes complications using temporal data mining.

Science.gov (United States)

Sacchi, Lucia; Dagliati, Arianna; Segagni, Daniele; Leporati, Paola; Chiovato, Luca; Bellazzi, Riccardo

2015-01-01

To understand which factor trigger worsened disease control is a crucial step in Type 2 Diabetes (T2D) patient management. The MOSAIC project, funded by the European Commission under the FP7 program, has been designed to integrate heterogeneous data sources and provide decision support in chronic T2D management through patients' continuous stratification. In this work we show how temporal data mining can be fruitfully exploited to improve risk stratification. In particular, we exploit administrative data on drug purchases to divide patients in meaningful groups. The detection of drug consumption patterns allows stratifying the population on the basis of subjects' purchasing attitude. Merging these findings with clinical values indicates the relevance of the applied methods while showing significant differences in the identified groups. This extensive approach emphasized the exploitation of administrative data to identify patterns able to explain clinical conditions.

Novel biomarkers for risk stratification in pulmonary arterial hypertension

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Thomas Zelniker

2015-10-01

Full Text Available Risk stratification in pulmonary arterial hypertension (PAH is paramount to identifying individuals at highest risk of death. So far, there are only limited parameters for prognostication in patients with PAH. 95 patients with confirmed PAH were included in the present analysis and followed for a total of 4 years. Blood samples were analysed for serum levels of N-terminal pro-brain natriuretic peptide, high-sensitivity troponin T (hsTnT, pro-atrial natriuretic peptide (proANP, growth differentiation factor 15, soluble fms-like tyrosine kinase 1 and placental growth factor. 27 (28.4% patients died during a follow-up of 4 years. Levels of all tested biomarkers, except for placental growth factor, were significantly elevated in nonsurvivors compared with survivors. Receiver operating characteristic analyses demonstrated that cardiac biomarkers had the highest power in predicting mortality. In particular, proANP exhibited the highest area under the curve, followed by N-terminal pro-brain natriuretic peptide and hsTnT. Furthermore, proANP and hsTnT added significant additive prognostic value to the established markers in categorical and continuous net reclassification index. Moreover, after Cox regression, proANP (hazard ratio (HR 1.91, hsTnT (HR 1.41, echocardiographic right ventricular impairment (HR 1.30 and 6-min walk test (HR 0.97 per 10 m remained the only significant parameters in prognostication of mortality. Our data suggest benefits of the implementation of proANP and hsTnT as additive biomarkers for risk stratification in patients with PAH.

An ischemia-guided approach for risk stratification in patients with acute coronary syndromes.

Science.gov (United States)

Pepine, C J

2000-12-28

The optimal management approach for patients with non-ST-segment elevation acute coronary syndromes continues to be an issue of debate. An ischemia-guided strategy appears to be effective as an alternative to either a very conservative "wait-and-see" approach or a very aggressive routine revascularization approach. The need for another approach is supported by the lack of conclusive evidence-based results favoring an early routine invasive treatment strategy. In the Thrombolysis in Myocardial Infarction (TIMI) IIIB trial, there were no differences in the incidence of death or myocardial infarction (MI) between patients treated with an early invasive approach and those treated with a conservative approach to treatment. Significantly worse outcomes were shown in patients assigned to an early invasive strategy in the Veterans Affairs Non-Q-Wave Infarction Strategies in Hospital (VANQWISH) trial at 1-year follow-up (111 clinical events in the invasive group vs 85 in the conservative group; p = 0.05). Registry information, including that from the Organization to Assess Strategies for Ischemic Syndromes (OASIS), which included approximately 8,000 patients with unstable angina or suspected MI, has even suggested an excess hazard with a routine invasive approach. Patients with non-ST-segment elevation MI observed in the Global Use of Strategies to Open Occluded Coronary Arteries in Acute Coronary Syndromes (GUSTO)-IIB and Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy (PURSUIT) trials also fared better with an ischemia-guided strategy. Even the recent FRagmin and Fast Revascularization during InStability in Coronary artery disease (FRISC II) trial investigators had to be very selective relative to eliminating high-risk patients in the first week and treating with intense anti-ischemic therapy and 5-7 days of low-molecular-weight heparin therapy to show an advantage for assigned revascularization. A careful clinical evaluation with

The Auckland Cataract Study II: Reducing Complications by Preoperative Risk Stratification and Case Allocation in a Teaching Hospital.

Science.gov (United States)

Kim, Bia Z; Patel, Dipika V; McKelvie, James; Sherwin, Trevor; McGhee, Charles N J

2017-09-01

To assess the effect of preoperative risk stratification for phacoemulsification surgery on intraoperative complications in a teaching hospital. Prospective cohort study. Prospective assessment of consecutive phacoemulsification cases (N = 500) enabled calculation of a risk score (M-score of 0-8) using a risk stratification system. M-scores of >3 were allocated to senior surgeons. All surgeries were performed in a public teaching hospital setting, Auckland, New Zealand, in early 2016. Postoperatively, data were reviewed for complications and corrected distance visual acuity (CDVA). Results were compared to a prospective study (N = 500, phase 1) performed prior to formal introduction of risk stratification. Intraoperative complications increased with increasing M-scores (P = .044). Median M-score for complicated cases was higher (P = .022). Odds ratio (OR) for a complication increased 1.269 per unit increase in M-score (95% confidence interval [CI] 1.007-1.599, P = .043). Overall rate of any intraoperative complication was 5.0%. Intraoperative complication rates decreased from 8.4% to 5.0% (OR = 0.576, P = .043) comparing phase 1 and phase 2 (formal introduction of risk stratification). The severity of complications also reduced. A significant decrease in complications for M = 0 (ie, minimal risk cases) was also identified comparing the current study (3.1%) to phase 1 (7.2%), P = .034. There was no change in postoperative complication risks (OR 0.812, P = .434) or in mean postoperative CDVA (20/30, P = .484) comparing current with phase 1 outcomes. A simple preoperative risk stratification system, based on standard patient information gathered at preoperative consultation, appears to reduce intraoperative complications and support safer surgical training by appropriate allocation of higher-risk cases. Copyright © 2017 Elsevier Inc. All rights reserved.

Current Roles and Future Applications of Cardiac CT: Risk Stratification of Coronary Artery Disease

Energy Technology Data Exchange (ETDEWEB)

Yoon, Yeonyee Elizabeth [Department of Cardiology, Cardiovascular Center, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Lim, Tae-Hwan [Department of Radiology and Research Institute of Radiology, University of Ulsan College of Medicine, Asan Medical Center, Seoul 138-736 (Korea, Republic of)

2014-07-01

Cardiac computed tomography (CT) has emerged as a noninvasive modality for the assessment of coronary artery disease (CAD), and has been rapidly integrated into clinical cares. CT has changed the traditional risk stratification based on clinical risk to image-based identification of patient risk. Cardiac CT, including coronary artery calcium score and coronary CT angiography, can provide prognostic information and is expected to improve risk stratification of CAD. Currently used conventional cardiac CT, provides accurate anatomic information but not functional significance of CAD, and it may not be sufficient to guide treatments such as revascularization. Recently, myocardial CT perfusion imaging, intracoronary luminal attenuation gradient, and CT-derived computed fractional flow reserve were developed to combine anatomical and functional data. Although at present, the diagnostic and prognostic value of these novel technologies needs to be evaluated further, it is expected that all-in-one cardiac CT can guide treatment and improve patient outcomes in the near future.

An operative dengue risk stratification system in Argentina based on geospatial technology

Directory of Open Access Journals (Sweden)

Ximena Porcasi

2012-09-01

Full Text Available Based on an agreement between the Ministry of Health and the National Space Activities Commission in Argentina, an integrated informatics platform for dengue risk using geospatial technology for the surveillance and prediction of risk areas for dengue fever has been designed. The task was focused on developing stratification based on environmental (historical and current, viral, social and entomological situation for >3,000 cities as part of a system. The platform, developed with open-source software with pattern design, following the European Space Agency standards for space informatics, delivers two products: a national risk map consisting of point vectors for each city/town/locality and an approximate 50 m resolution urban risk map modelling the risk inside selected high-risk cities. The operative system, architecture and tools used in the development are described, including a detailed list of end users’ requirements. Additionally, an algorithm based on bibliography and landscape epidemiology concepts is presented and discussed. The system, in operation since September 2011, is capable of continuously improving the algorithms producing improved risk stratifications without a complete set of inputs. The platform was specifically developed for surveillance of dengue fever as this disease has reemerged in Argentina but the aim is to widen the scope to include also other relevant vector-borne diseases such as chagas, malaria and leishmaniasis as well as other countries belonging to south region of Latin America.

Risk stratification by endocrinologists of patients with type 2 diabetes in a Danish specialised outpatient clinic

DEFF Research Database (Denmark)

Munch, Lene; Arreskov, Anne B; Sperling, Michael

2016-01-01

BACKGROUND: To target optimised medical care the Danish guidelines for diabetes recommend stratification of patients with type 2 diabetes (T2D) into three levels according to risk and complexity of treatment. The aim was to describe the T2D population in an outpatient clinic, measure the compliance......, the endocrinologists stratified less patients at level 3 compared to objective assessments (p Type 2 diabetes patients, newly referred to or allocated for long-term follow-up in the out...... contained the following criteria: HbA1c, blood pressure, metabolic complications, microvascular and macrovascular complications. Stratification levels encompassed: level 1 (uncomplicated), level 2 (intermediate risk) and level 3 (high risk). Objective assessments were conducted independently by two health...

Ventricular repolarization measures for arrhythmic risk stratification

Institute of Scientific and Technical Information of China (English)

Francesco Monitillo; Marta Leone; Caterina Rizzo; Andrea Passantino; Massimo Iacoviello

2016-01-01

Ventricular repolarization is a complex electrical phenomenon which represents a crucial stage in electrical cardiac activity. It is expressed on the surface electrocardiogram by the interval between the start of the QRS complex and the end of the T wave or U wave(QT). Several physiological, pathological and iatrogenic factors can influence ventricular repolarization. It has been demonstrated that small perturbations in this process can be a potential trigger of malignant arrhythmias, therefore the analysis of ventricular repolarization represents an interesting tool to implement risk stratification of arrhythmic events in different clinical settings. The aim of this review is to critically revise the traditional methods of static analysis of ventricular repolarization as well as those for dynamic evaluation, their prognostic significance and the possible application in daily clinical practice.

[The scoring system for the risk-stratification in patients with the antiphospholipid syndrome].

Science.gov (United States)

Oku, Kenji

2017-01-01

  Antiphospholipid syndrome (APS) is a clinical disorder characterized by thrombosis and/or pregnancy morbidity in the persistence of the pathogenic autoantibodies, the antiphospholipid antibodies (aPL). Recurernt thrombosis is often observed in patients with APS which requires persistent prophylaxis. However, an uniform prophylactic treatment for APS patients is inadequate and stratification of the thrombotic risks is important as aPL are prevalently observed in other various diseases or elderly population. It is previously known that the multiple positivity or high titre of aPL correlate to the thrombotic events. To progress the stratification of the thrombotic risks and to quantitatively analyze them, antiphospholipid score (aPL-S) and the Global Anti-Phospholipid Syndrome Score (GAPSS) were defined as the scoring-systems. Both of these scoring-systems were raised from the large patient cohort data and either aPL profile classified in detail (aPL-S) or simplified aPL profile with classical thrombotic risk factors (GAPSS) were put into scoring system. They have shown a degree of accuracy in identifying high-risk APS patients, especially those at a high risk of thrombosis. However, there are several areas requiring improvement, or at least that clinicians should be aware of, before these instruments are applied in clinical practice. One such issue is standardisation of the aPL tests, including general testing of phosphatidylserine dependent antiprothrombin antibodies (aPS/PT).

Molecular risk stratification of medulloblastoma patients based on immunohistochemical analysis of MYC, LDHB, and CCNB1 expression

NARCIS (Netherlands)

de Haas, Talitha; Hasselt, Nancy; Troost, Dirk; Caron, Huib; Popovic, Mara; Zadravec-Zaletel, Lorna; Grajkowska, Wieslawa; Perek, Marta; Osterheld, Maria-Chiara; Ellison, David; Baas, Frank; Versteeg, Rogier; Kool, Marcel

2008-01-01

PURPOSE: Medulloblastoma is the most common malignant embryonal brain tumor in children. The current clinical risk stratification to select treatment modalities is not optimal because it does not identify the standard-risk patients with resistant disease or the unknown number of high-risk patients

Plaque Tissue Morphology-Based Stroke Risk Stratification Using Carotid Ultrasound: A Polling-Based PCA Learning Paradigm.

Science.gov (United States)

Saba, Luca; Jain, Pankaj K; Suri, Harman S; Ikeda, Nobutaka; Araki, Tadashi; Singh, Bikesh K; Nicolaides, Andrew; Shafique, Shoaib; Gupta, Ajay; Laird, John R; Suri, Jasjit S

2017-06-01

Severe atherosclerosis disease in carotid arteries causes stenosis which in turn leads to stroke. Machine learning systems have been previously developed for plaque wall risk assessment using morphology-based characterization. The fundamental assumption in such systems is the extraction of the grayscale features of the plaque region. Even though these systems have the ability to perform risk stratification, they lack the ability to achieve higher performance due their inability to select and retain dominant features. This paper introduces a polling-based principal component analysis (PCA) strategy embedded in the machine learning framework to select and retain dominant features, resulting in superior performance. This leads to more stability and reliability. The automated system uses offline image data along with the ground truth labels to generate the parameters, which are then used to transform the online grayscale features to predict the risk of stroke. A set of sixteen grayscale plaque features is computed. Utilizing the cross-validation protocol (K = 10), and the PCA cutoff of 0.995, the machine learning system is able to achieve an accuracy of 98.55 and 98.83%corresponding to the carotidfar wall and near wall plaques, respectively. The corresponding reliability of the system was 94.56 and 95.63%, respectively. The automated system was validated against the manual risk assessment system and the precision of merit for same cross-validation settings and PCA cutoffs are 98.28 and 93.92%for the far and the near wall, respectively.PCA-embedded morphology-based plaque characterization shows a powerful strategy for risk assessment and can be adapted in clinical settings.

Application of support vector machine classifiers to preoperative risk stratification with myocardial perfusion scintigraphy

International Nuclear Information System (INIS)

Kasamatsu, Tomotaka; Hashimoto, Jun; Nakahara, Tadaki; Bai, Jingming; Kitamura, Naoto; Kubo, Atsushi; Iyatomi, Hitoshi; Ogawa, Koichi

2008-01-01

Myocardial perfusion single-photon emission computed tomography (SPECT) has been used for risk stratification before non-cardiac surgery. However, few authors have used mathematical models for evaluating the likelihood of perioperative cardiac events. This retrospective cohort study collected data of 1,351 patients referred for SPECT before non-cardiac surgery. We generated binary classifiers using support vector machine (SVM) and conventional linear models for predicting perioperative cardiac events. We used clinical and surgical risk, and SPECT findings as input data, and the occurrence of all and hard cardiac events as output data. The area under the receiver-operating characteristic curve (AUC) was calculated for assessing the prediction accuracy. The AUC values were 0.884 and 0.748 in the SVM and linear models, respectively in predicting all cardiac events with clinical and surgical risk, and SPECT variables. The values were 0.861 (SVM) and 0.677 (linear) when not using SPECT data as input. In hard events, the AUC values were 0.892 (SVM) and 0.864 (linear) with SPECT, and 0.867 (SVM) and 0.768 (linear) without SPECT. The SVM was superior to the linear model in risk stratification. We also found an incremental prognostic value of SPECT results over information about clinical and surgical risk. (author)

Analysis of agreement between cardiac risk stratification protocols applied to participants of a center for cardiac rehabilitation

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Ana A. S. Santos

2016-01-01

Full Text Available ABSTRACT Background Cardiac risk stratification is related to the risk of the occurrence of events induced by exercise. Despite the existence of several protocols to calculate risk stratification, studies indicating that there is similarity between these protocols are still unknown. Objective To evaluate the agreement between the existing protocols on cardiac risk rating in cardiac patients. Method The records of 50 patients from a cardiac rehabilitation program were analyzed, from which the following information was extracted: age, sex, weight, height, clinical diagnosis, medical history, risk factors, associated diseases, and the results from the most recent laboratory and complementary tests performed. This information was used for risk stratification of the patients in the protocols of the American College of Sports Medicine, the Brazilian Society of Cardiology, the American Heart Association, the protocol designed by Frederic J. Pashkow, the American Association of Cardiovascular and Pulmonary Rehabilitation, the Société Française de Cardiologie, and the Sociedad Española de Cardiología. Descriptive statistics were used to characterize the sample and the analysis of agreement between the protocols was calculated using the Kappa coefficient. Differences were considered with a significance level of 5%. Results Of the 21 analyses of agreement, 12 were considered significant between the protocols used for risk classification, with nine classified as moderate and three as low. No agreements were classified as excellent. Different proportions were observed in each risk category, with significant differences between the protocols for all risk categories. Conclusion The agreements between the protocols were considered low and moderate and the risk proportions differed between protocols.

Clinical impact and risk stratification of balloon angioplasty for femoropopliteal disease in nitinol stenting era: Retrospective multicenter study using propensity score matching analysis

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Taketsugu Tsuchiya

2016-07-01

Full Text Available Objective: Nitinol stenting could bring the better outcome in endovascular therapy for femoropopliteal disease. However, it might be expected that recent marked advances in both device technology and operator technique had led to improved efficacy of balloon angioplasty even in this segment. The aims of this study were to evaluate the clinical impact of balloon angioplasty for femoropopliteal disease and make risk stratification clear by propensity score matching analysis. Methods: Based on the multicenter retrospective data, 2758 patients (balloon angioplasty: 729 patients and nitinol stenting: 2029 patients, those who underwent endovascular therapy for femoropopliteal disease, were analyzed. Results: The propensity score matching procedure extracted a total of 572 cases per group, and the primary patency rate of balloon angioplasty and nitinol stenting groups after matching was significantly the same (77.2% vs 82.7% at 1 year; 62.2% vs 64.3% at 3 years; 47.8% vs 54.3% at 5 years. In multivariate Cox hazard regression analysis, significant predictors for primary patency were diabetes mellitus, regular dialysis, cilostazol use, chronic total occlusion, and intra-vascular ultra-sonography use. The strategy of balloon angioplasty was not evaluated as a significant predictor for the primary patency. After risk stratification using five items (diabetes mellitus, regular dialysis, no use of intra-vascular ultra-sonography, chronic total occlusion, and no use of cilostazol: the DDICC score, the estimated primary patency rates of each group (low, DDICC score 0–2; moderate, DDICC score 3; high risk, DDICC score 4–5 were 88.6%, 78.3%, and 63.5% at 1 year; 75.2%, 60.7%, and 39.8% at 3 years; and 66.0%, 47.1%, and 26.3% at 5 years (p < 0.0001. The primary patency rate of balloon angioplasty and nitinol stenting groups was significantly the same in each risk stratification. Conclusion: This study suggests that balloon angioplasty does

Biomarkers for Risk Stratification of Neoplastic Progression in Barrett Esophagus

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Marjon Kerkhof

2007-01-01

Full Text Available Barrett esophagus (BE is caused by chronic gastroesophageal reflux and predisposes to the development of esophageal adenocarcinoma through different grades of dysplasia. Only a subset of BE patients will finally develop esophageal adenocarcinoma. The majority will therefore not benefit from an endoscopic surveillance program, based on the histological identification of dysplasia. Several studies have been performed to find additional biomarkers that can be used to detect the subgroup of patients with an increased risk of developing malignancy in BE. In this review, we will summarize the most promising tissue biomarkers, i.e. proliferation/cell cycle proteins, tumor suppressor genes, adhesion molecules, DNA ploidy status and inflammation associated markers, that can be used for risk stratification in BE, and discuss their respective clinical application.

A risk stratification model for antihypertensive medication non-adherence among Chinese immigrants

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Wen-Wen Li

2016-12-01

Full Text Available The purpose of this study was to establish a risk stratification model for identifying Chinese immigrants at risk for non-adherence to antihypertensive medications. Questionnaires were self-administered to 200 Chinese immigrants in San Francisco, USA. Questionnaires included demographics, culture factors (e.g., Perceived Susceptibility in General, Perceived Benefits of Western Medication, Perceived Benefits of Chinese Herbs, and Health-Related Social Support, and medications adherence. Participants' mean age was 70.6 (±10.3 years. Three stratification factors were identified for non-adherence: Lower Perceived Susceptibility in General, lower Perceived Benefit of Western Medications, and longer Length of Stay in the United States. The probability of non-adherence was 77%, 62%, and 57% for lower perceived susceptibility, longer stay in the United States, and lower perceived benefits of Western medications, respectively. A combination of lower perceived susceptibility and lower perceived benefits of medication predicted 81% non-adherence and lower perceived susceptibility with longer stay in the United States predicted at 84%. All three factors combined predicted nearly 90%. Patients with all three factors had the highest risk for non-adherence. The second priority groups are patients with lower perceived susceptibility and those with lower perceived susceptibility combined with any of the other two factors. In the clinical setting, these three groups are a high priority for education on the importance of medication adherence.

Multiinstitutional Analysis of Thyroid Nodule Risk Stratification Using the American College of Radiology Thyroid Imaging Reporting and Data System.

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Middleton, William D; Teefey, Sharlene A; Reading, Carl C; Langer, Jill E; Beland, Michael D; Szabunio, Margaret M; Desser, Terry S

2017-06-01

Guidelines for managing thyroid nodules are highly dependent on risk stratification based on sonographic findings. The purpose of this study is to evaluate the risk stratification system used by the American College of Radiology Thyroid Imaging Reporting and Data System (TIRADS). Patients with thyroid nodules who underwent sonography and fine-needle aspiration were enrolled in a multiinstitutional study. The sonographic nodule features evaluated in the study were composition, echogenicity, margins, and echogenic foci. Images were reviewed by two radiologists who were blinded to the results of cytologic analysis. Nodules were assigned points for each feature, and the points were totaled to determine the final TIRADS level (TR1-TR5). The risk of cancer associated with each point total and final TIRADS level was determined. A total of 3422 nodules, 352 of which were malignant, were studied. The risk of malignancy was closely associated with the composition, echogenicity, margins, and echogenic foci of the nodules (p 474 nodules that were more than 1% outside these thresholds, 88.0% (417/474) had a risk level that was below the TIRADS threshold. The aggregate risk of malignancy for nodules associated with each individual TIRADS point level (0-10) and each final TIRADS level (TR1-TR5) falls within the TIRADS risk stratification thresholds. A total of 85% of all nodules were within 1% of the specified TIRADS risk thresholds.

Magnetic Resonance Imaging Plaque Hemorrhage for Risk Stratification in Carotid Artery Disease With Moderate Risk Under Current Medical Therapy.

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Hosseini, Akram A; Simpson, Richard J; Altaf, Nishath; Bath, Philip M; MacSweeney, Shane T; Auer, Dorothee P

2017-03-01

Magnetic resonance imaging (MRI)-defined carotid plaque hemorrhage (MRIPH) can predict recurrent cerebrovascular ischemic events in severe symptomatic carotid stenosis. It is less clear whether MRIPH can improve risk stratification despite optimized medical secondary prevention in those with moderate risk. One-hundred fifty-one symptomatic patients with 30% to 99% carotid artery stenosis (median age: 77, 60.5% men) clinically deemed to not benefit from endarterectomy were prospectively recruited to undergo MRI and clinical follow-up (mean, 22 months). The clinical carotid artery risk score could be evaluated in 88 patients. MRIPH+ve was defined as plaque intensity >150% that of adjacent muscle. Survival analyses were performed with recurrent infarction (stroke or diffusion-positive cerebral ischemia) as the main end point. Fifty-five participants showed MRIPH+ve; 47 had low, 36 intermediate, and 5 high carotid artery risk scores. Cox regression showed MRIPH as a strong predictor of future infarction (hazard ratio, 5.2; 95% confidence interval, 1.64-16.34; P =0.005, corrected for degree of stenosis), also in the subgroup with 50% to 69% stenosis (hazard ratio, 4.1; 95% confidence interval, 1-16.8; P =0.049). The absolute risk of future infarction was 31.7% at 3 years in MRIPH+ve versus 1.8% in patients without ( P medication with clinically uncertain benefit from recanalization, that is, those with moderate degree stenosis and intermediate carotid artery risk scores, MRIPH offers additional risk stratification. © 2017 American Heart Association, Inc.

Perceptions of Risk Stratification Workflows in Primary Care

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Rachel L. Ross

2017-10-01

Full Text Available Risk stratification (RS in primary care is frequently used by policy-makers, payers, and health systems; the process requires risk assessment for adverse health outcomes across a population to assign patients into risk tiers and allow care management (CM resources to be targeted effectively. Our objective was to understand the approach to and perception of RS in primary care practices. An online survey was developed, tested, and administered to 148 representatives of 37 primary care practices engaged in RS varying in size, location and ownership. The survey assessed practices’ approach to, perception of, and confidence in RS, and its effect on subsequent CM activities. We examined psychometric properties of the survey to determine validity and conducted chi-square analyses to determine the association between practice characteristics and confidence and agreement with risk scores. The survey yielded a 68% response rate (100 respondents. Overall, participants felt moderately confident in their risk scores (range 41–53.8%, and moderately to highly confident in their subsequent CM workflows (range 46–68%. Respondents from small and independent practices were more likely to have higher confidence and agreement with their RS approaches and scores (p < 0.01. Confidence levels were highest, however, when practices incorporated human review into their RS processes (p < 0.05. This trend was not affected by respondents’ professional roles. Additional work from a broad mixed-methods effort will add to our understanding of RS implementation processes and outcomes.

Overcoming intratumoural heterogeneity for reproducible molecular risk stratification: a case study in advanced kidney cancer.

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Lubbock, Alexander L R; Stewart, Grant D; O'Mahony, Fiach C; Laird, Alexander; Mullen, Peter; O'Donnell, Marie; Powles, Thomas; Harrison, David J; Overton, Ian M

2017-06-26

Metastatic clear cell renal cell cancer (mccRCC) portends a poor prognosis and urgently requires better clinical tools for prognostication as well as for prediction of response to treatment. Considerable investment in molecular risk stratification has sought to overcome the performance ceiling encountered by methods restricted to traditional clinical parameters. However, replication of results has proven challenging, and intratumoural heterogeneity (ITH) may confound attempts at tissue-based stratification. We investigated the influence of confounding ITH on the performance of a novel molecular prognostic model, enabled by pathologist-guided multiregion sampling (n = 183) of geographically separated mccRCC cohorts from the SuMR trial (development, n = 22) and the SCOTRRCC study (validation, n = 22). Tumour protein levels quantified by reverse phase protein array (RPPA) were investigated alongside clinical variables. Regularised wrapper selection identified features for Cox multivariate analysis with overall survival as the primary endpoint. The optimal subset of variables in the final stratification model consisted of N-cadherin, EPCAM, Age, mTOR (NEAT). Risk groups from NEAT had a markedly different prognosis in the validation cohort (log-rank p = 7.62 × 10 -7 ; hazard ratio (HR) 37.9, 95% confidence interval 4.1-353.8) and 2-year survival rates (accuracy = 82%, Matthews correlation coefficient = 0.62). Comparisons with established clinico-pathological scores suggest favourable performance for NEAT (Net reclassification improvement 7.1% vs International Metastatic Database Consortium score, 25.4% vs Memorial Sloan Kettering Cancer Center score). Limitations include the relatively small cohorts and associated wide confidence intervals on predictive performance. Our multiregion sampling approach enabled investigation of NEAT validation when limiting the number of samples analysed per tumour, which significantly degraded performance

Risk stratification using lean body mass in patients undergoing transcatheter aortic valve replacement.

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Hioki, Hirofumi; Watanabe, Yusuke; Kozuma, Ken; Yamamoto, Masanori; Naganuma, Toru; Araki, Motoharu; Tada, Norio; Shirai, Shinichi; Yamanaka, Futoshi; Higashimori, Akihiro; Mizutani, Kazuki; Tabata, Minoru; Takagi, Kensuke; Ueno, Hiroshi; Hayashida, Kentaro

2018-02-22

The prognostic impact of skeletal muscle mass, assessed using lean body mass (LBM), remain unclear in patients who underwent transcatheter aortic valve replacement (TAVR). The aim of this study to assess prognostic impact of LBM on mortality after TAVR. We assessed 1,613 patients (median age 85 years, 70% female) who underwent TAVI from October 2013 to April 2016 using OCEAN (Optimized transCathEter vAlvular interveNtion)-TAVI registry data. LBM was calculated using the James formula. The primary endpoint was all-cause death after TAVR. Median follow-up period was 287 days (interquartile range 110-462). The Kaplan-Meier analysis demonstrated that patients with low LBM had significantly higher incidence of all-cause death than those with high LBM in male (32.3% vs. 9.9%, log rank P LBM was an independent predictor of all-cause death in male (Hazard ratio [HR] 0.93; 95% confidence interval [CI] 0.89-0.98) and female (HR 0.94; 95% CI 0.89-0.99). Inversely, the assessment using BMI could not identify the high-risk population in a female. The patients with low LBM had the higher incidence of all-cause death after TAVR than those with high LBM, regardless of gender. Thus, the risk stratification using LBM might provide further insight to identify the high-risk TAVR population, compared to conventional risk stratification using BMI. © 2018 Wiley Periodicals, Inc.

Fuel and combustion stratification study of Partially Premixed Combustion

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Izadi Najafabadi, M.; Dam, N.; Somers, B.; Johansson, B.

2016-01-01

Relatively high levels of stratification is one of the main advantages of Partially Premixed Combustion (PPC) over the Homogeneous Charge Compression Ignition (HCCI) concept. Fuel stratification smoothens heat release and improves controllability of this kind of combustion. However, the lack of a clear definition of “fuel and combustion stratifications” is obvious in literature. Hence, it is difficult to compare stratification levels of different PPC strategies or other combustion concepts. T...

[Risk stratification of patients with diabetes mellitus undergoing coronary artery bypass grafting--a comparison of statistical methods].

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Arnrich, B; Albert, A; Walter, J

2006-01-01

Among the coronary bypass patients from our Datamart database, we found a prevalence of 29.6% of diagnosed diabetics. 5.2% of the patients without a diagnosis of diabetes mellitus and a fasting plasma glucose level > 125 mg/dl were defined as undiagnosed diabetics. The objective of this paper was to compare univariate methods and techniques for risk stratification to determine, whether undiagnosed diabetes is per se a risk factor for increased ventilation time and length of ICU stay, and for increased prevalence of resuscitation, reintubation and 30-d mortality for diabetics in heart surgery. Univariate comparisons reveals that undiagnosed diabetics needed resuscitation significantly more often and had an increased ventilation time, while the length of ICU stay was significantly reduced. The significantly different distribution between the diabetics groups of 11 from 32 attributes examined, demands the use of methods for risk stratification. Both risk adjusted methods regression and matching confirm that undiagnosed diabetics had an increased ventilation time and an increased prevalence of resuscitation, while the length of ICU stay was not significantly reduced. A homogeneous distribution of the patient characteristics in the two diabetics groups could be achieved through a statistical matching method using the propensity score. In contrast to the regression analysis, a significantly increased prevalence of reintubation in undiagnosed diabetics was found. Based on an example of undiagnosed diabetics in heart surgery, the presented study reveals the necessity and the possibilities of techniques for risk stratification in retrospective analysis and shows how the potential of data collection from daily clinical practice can be used in an effective way.

Cloning of the first human anti-JCPyV/VP1 neutralizing monoclonal antibody: epitope definition and implications in risk stratification of patients under natalizumab therapy.

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Diotti, Roberta Antonia; Mancini, Nicasio; Clementi, Nicola; Sautto, Giuseppe; Moreno, Guisella Janett; Criscuolo, Elena; Cappelletti, Francesca; Man, Petr; Forest, Eric; Remy, Louise; Giannecchini, Simone; Clementi, Massimo; Burioni, Roberto

2014-08-01

JC virus (JCPyV) has gained novel clinical importance as cause of progressive multifocal leukoencephalopathy (PML), a rare demyelinating disease recently associated to immunomodulatory drugs, such as natalizumab used in multiple sclerosis (MS) cases. Little is known about the mechanisms leading to PML, and this makes the need of PML risk stratification among natalizumab-treated patients very compelling. Clinical and laboratory-based risk-stratification markers have been proposed, one of these is represented by the JCPyV-seropositive status, which includes about 54% of MS patients. We recently proposed to investigate the possible protective role of neutralizing humoral immune response in preventing JCPyV reactivation. In this proof-of-concept study, by cloning the first human monoclonal antibody (GRE1) directed against a neutralizing epitope on JCPyV/VP1, we optimized a robust anti-JCPyV neutralization assay. This allowed us to evaluate the neutralizing activity in JCPyV-positive sera from MS patients, demonstrating the lack of correlation between the level of anti-JCPyV antibody and anti-JCPyV neutralizing activity. Relevant consequences may derive from future clinical studies induced by these findings; indeed the study of the serum anti-JCPyV neutralizing activity could allow not only a better risk stratification of the patients during natalizumab treatment, but also a better understanding of the pathophysiological mechanisms leading to PML, highlighting the contribution of peripheral versus central nervous system JCPyV reactivation. Noteworthy, the availability of GRE1 could allow the design of novel immunoprophylactic strategies during the immunomodulatory treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

Risk stratification for progressive multifocal leukoencephalopathy in patients treated with natalizumab

DEFF Research Database (Denmark)

Sørensen, Per Soelberg; Bertolotto, Antonio; Edan, Gilles

2012-01-01

using or considering natalizumab therapy. Recommendations for clinical management of patients with MS and use of natalizumab are provided based on the presence of these three risk factors. The identification of risk factors that increase the likelihood of PML in natalizumab-treated patients can......Natalizumab is a highly effective immunomodulator in the treatment of multiple sclerosis (MS). Treatment with natalizumab has been associated with progressive multifocal leukoencephalopathy (PML), an infection of the central nervous system (CNS) caused by a pathogenic form of the normally benign JC......-treated patients. With the development of a reliable and validated assay for detection of antibodies in patients with MS directed against JCV, it is now possible to identify persons who are carriers of JCV. The availability of this assay provides an additional option for risk stratification of PML in patients...

Early Risk stratification for Arrhythmic death in Patients with ST-Elevation Myocardial Infarction

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Mohammad Ali Sadr-Ameli

2007-01-01

Full Text Available Background: Sudden cardiac death is a leading cause of death in patients with ST-elevation myocardial infarction (MI. According to high cost of modern therapeutic modalities it is of paramount importance to define protocols for risk stratification of post-MI patients before considering expensive devices such as implantable cardioverter-defibrillator.Methods: One hundred and thirty seven patients with acute ST-elevation MI were selected and underwent echocardiographic study, holter monitoring and signal-averaged electrocardiography (SAECG. Then, the patients were followed for 12 ±3 months.Results: During follow-up, 13 deaths (9.5% occurred; nine cases happened as sudden cardiac death (6.6%. The effect of ejection fraction (EF less than 40% on occurrence of arrhythmic events was significant (P<0.001. Sensitivity and positive predictive value of EF<40% was 100% and 76.95% respectively. Although with lesser sensitivity and predictive power than EF<40%, abnormal heart rate variability (HRV and SAECG had also significant effects on occurrence of sudden death (P=0.02 and P=0.003 respectively. Nonsustained ventricular tachycardia was not significantly related to risk of sudden death in this study (P=0.20.Conclusions: This study indicated that EF less than 40% is the most powerful predictor of sudden cardiac death in post MI patients. Abnormal HRV and SAECG are also important predictors and can be added to EF for better risk stratification.

Stratification of the Risk of Sudden Death in Nonischemic Heart Failure

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Maurício Pimentel

2014-10-01

Full Text Available Despite significant therapeutic advancements, heart failure remains a highly prevalent clinical condition associated with significant morbidity and mortality. In 30%-40% patients, the etiology of heart failure is nonischemic. The implantable cardioverter-defibrillator (ICD is capable of preventing sudden death and decreasing total mortality in patients with nonischemic heart failure. However, a significant number of patients receiving ICD do not receive any kind of therapy during follow-up. Moreover, considering the situation in Brazil and several other countries, ICD cannot be implanted in all patients with nonischemic heart failure. Therefore, there is an urgent need to identify patients at an increased risk of sudden death because these would benefit more than patients at a lower risk, despite the presence of heart failure in both risk groups. In this study, the authors review the primary available methods for the stratification of the risk of sudden death in patients with nonischemic heart failure.

A novel approach to population-based risk stratification, comprising individualized lifestyle intervention in Danish general practice to prevent chronic diseases

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Bruun Larsen, Lars; Søndergaard, Jens; Halling, Anders

2017-01-01

Early detection of patients at risk seems to be effective for reducing the prevalence of lifestyle-related chronic diseases. We aim to test the feasibility of a novel intervention for early detection of lifestyle-related chronic diseases based on a population-based stratification using a combinat......Early detection of patients at risk seems to be effective for reducing the prevalence of lifestyle-related chronic diseases. We aim to test the feasibility of a novel intervention for early detection of lifestyle-related chronic diseases based on a population-based stratification using...

Prognostic factors and risk stratification in patients with castration-resistant prostate cancer receiving docetaxel-based chemotherapy.

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Yamashita, Shimpei; Kohjimoto, Yasuo; Iguchi, Takashi; Koike, Hiroyuki; Kusumoto, Hiroki; Iba, Akinori; Kikkawa, Kazuro; Kodama, Yoshiki; Matsumura, Nagahide; Hara, Isao

2016-03-22

While novel drugs have been developed, docetaxel remains one of the standard initial systemic therapies for castration-resistant prostate cancer (CRPC) patients. Despite the excellent anti-tumor effect of docetaxel, its severe adverse effects sometimes distress patients. Therefore, it would be very helpful to predict the efficacy of docetaxel before treatment. The aims of this study were to evaluate the potential value of patient characteristics in predicting overall survival (OS) and to develop a risk classification for CRPC patients treated with docetaxel-based chemotherapy. This study included 79 patients with CRPC treated with docetaxel. The variables, including patient characteristics at diagnosis and at the start of chemotherapy, were retrospectively collected. Prognostic factors predicting OS were analyzed using the Cox proportional hazard model. Risk stratification for overall survival was determined based on the results of multivariate analysis. PSA response ≥50 % was observed in 55 (69.6 %) of all patients, and the median OS was 22.5 months. The multivariate analysis showed that age, serum PSA level at the start of chemotherapy, and Hb were independent prognostic factors for OS. In addition, ECOG performance status (PS) and the CRP-to-albumin ratio were not significant but were considered possible predictors for OS. Risk stratification according to the number of these risk factors could effectively stratify CRPC patients treated with docetaxel in terms of OS. Age, serum PSA level at the start of chemotherapy, and Hb were identified as independent prognostic factors of OS. ECOG PS and the CRP-to-albumin ratio were not significant, but were considered possible predictors for OS in Japanese CRPC patients treated with docetaxel. Risk stratification based on these factors could be helpful for estimating overall survival.

An Interoperable System toward Cardiac Risk Stratification from ECG Monitoring

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Cristina Soguero-Ruiz

2018-03-01

Full Text Available Many indices have been proposed for cardiovascular risk stratification from electrocardiogram signal processing, still with limited use in clinical practice. We created a system integrating the clinical definition of cardiac risk subdomains from ECGs and the use of diverse signal processing techniques. Three subdomains were defined from the joint analysis of the technical and clinical viewpoints. One subdomain was devoted to demographic and clinical data. The other two subdomains were intended to obtain widely defined risk indices from ECG monitoring: a simple-domain (heart rate turbulence (HRT, and a complex-domain (heart rate variability (HRV. Data provided by the three subdomains allowed for the generation of alerts with different intensity and nature, as well as for the grouping and scrutinization of patients according to the established processing and risk-thresholding criteria. The implemented system was tested by connecting data from real-world in-hospital electronic health records and ECG monitoring by considering standards for syntactic (HL7 messages and semantic interoperability (archetypes based on CEN/ISO EN13606 and SNOMED-CT. The system was able to provide risk indices and to generate alerts in the health records to support decision-making. Overall, the system allows for the agile interaction of research and clinical practice in the Holter-ECG-based cardiac risk domain.

An Interoperable System toward Cardiac Risk Stratification from ECG Monitoring

Science.gov (United States)

Mora-Jiménez, Inmaculada; Ramos-López, Javier; Quintanilla Fernández, Teresa; García-García, Antonio; Díez-Mazuela, Daniel; García-Alberola, Arcadi

2018-01-01

Many indices have been proposed for cardiovascular risk stratification from electrocardiogram signal processing, still with limited use in clinical practice. We created a system integrating the clinical definition of cardiac risk subdomains from ECGs and the use of diverse signal processing techniques. Three subdomains were defined from the joint analysis of the technical and clinical viewpoints. One subdomain was devoted to demographic and clinical data. The other two subdomains were intended to obtain widely defined risk indices from ECG monitoring: a simple-domain (heart rate turbulence (HRT)), and a complex-domain (heart rate variability (HRV)). Data provided by the three subdomains allowed for the generation of alerts with different intensity and nature, as well as for the grouping and scrutinization of patients according to the established processing and risk-thresholding criteria. The implemented system was tested by connecting data from real-world in-hospital electronic health records and ECG monitoring by considering standards for syntactic (HL7 messages) and semantic interoperability (archetypes based on CEN/ISO EN13606 and SNOMED-CT). The system was able to provide risk indices and to generate alerts in the health records to support decision-making. Overall, the system allows for the agile interaction of research and clinical practice in the Holter-ECG-based cardiac risk domain. PMID:29494497

A Practical Risk Stratification Approach for Implementing a Primary Care Chronic Disease Management Program in an Underserved Community.

Science.gov (United States)

Xu, Junjun; Williams-Livingston, Arletha; Gaglioti, Anne; McAllister, Calvin; Rust, George

2018-01-01

The use of value metrics is often dependent on payer-initiated health care management incentives. There is a need for practices to define and manage their own patient panels regardless of payer to participate effectively in population health management. A key step is to define a panel of primary care patients with high comorbidity profiles. Our sample included all patients seen in an urban academic family medicine clinic over a two-year period. The simplified risk stratification was built using internal electronic health record and billing system data based on ICD-9 codes. There were 347 patients classified as high-risk out of the 5,364 patient panel. Average age was 59 years (SD 15). Hypertension (90%), hyperlipidemia (62%), and depression (55%) were the most common conditions among high-risk patients. Simplified risk stratification provides a feasible option for our team to understand and respond to the nuances of population health in our underserved community.

Advanced colorectal neoplasia risk stratification by penalized logistic regression.

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Lin, Yunzhi; Yu, Menggang; Wang, Sijian; Chappell, Richard; Imperiale, Thomas F

2016-08-01

Colorectal cancer is the second leading cause of death from cancer in the United States. To facilitate the efficiency of colorectal cancer screening, there is a need to stratify risk for colorectal cancer among the 90% of US residents who are considered "average risk." In this article, we investigate such risk stratification rules for advanced colorectal neoplasia (colorectal cancer and advanced, precancerous polyps). We use a recently completed large cohort study of subjects who underwent a first screening colonoscopy. Logistic regression models have been used in the literature to estimate the risk of advanced colorectal neoplasia based on quantifiable risk factors. However, logistic regression may be prone to overfitting and instability in variable selection. Since most of the risk factors in our study have several categories, it was tempting to collapse these categories into fewer risk groups. We propose a penalized logistic regression method that automatically and simultaneously selects variables, groups categories, and estimates their coefficients by penalizing the [Formula: see text]-norm of both the coefficients and their differences. Hence, it encourages sparsity in the categories, i.e. grouping of the categories, and sparsity in the variables, i.e. variable selection. We apply the penalized logistic regression method to our data. The important variables are selected, with close categories simultaneously grouped, by penalized regression models with and without the interactions terms. The models are validated with 10-fold cross-validation. The receiver operating characteristic curves of the penalized regression models dominate the receiver operating characteristic curve of naive logistic regressions, indicating a superior discriminative performance. © The Author(s) 2013.

Diabetes mellitus and bone health: epidemiology, etiology and implications for fracture risk stratification.

Science.gov (United States)

Valderrábano, Rodrigo J; Linares, Maria I

2018-01-01

Skeletal fractures can result when there are co-morbid conditions that negatively impact bone strength. Fractures represent an important source of morbidity and mortality, especially in older populations. Diabetes mellitus is a metabolic disorder that has reached worldwide epidemic proportions and is increasingly being recognized as a risk factor for fracture. Type 1 and Type 2 diabetes have different effects on bone mineral density but share common pathways, which lead to bone fragility. In this review, we discuss the available data on diabetes and fractures, bone density and the clinical implications for fracture risk stratification in current practice.

Risk stratification of patients with advanced squamous cell carcinoma of cervix treated by radiotherapy alone

International Nuclear Information System (INIS)

Hong, J.-H.; Tsai, C.-S.; Lai, C.-H.; Chang, T.-C.; Wang, C.-C.; Chou, H.-H.; Lee, Steve P.; Lee, C.-C.; Tang, Simon G.; Hsueh Swei

2005-01-01

Purpose: To identify prognostic factors for local and distant relapse and perform risk stratification for patients with advanced cervical cancer treated with radiotherapy (RT) alone. Methods and Materials: A total of 1031 patients with Stage IB-IVA squamous cell carcinoma of the cervix treated with full-course RT but without any chemotherapy were included for analysis. Of these, 311 patients with nonbulky Stage IB-IIA disease were designated the reference group and the other 720 patients were the study group. The associations of stage, squamous cell carcinoma antigen (SCC-ag) level, hemoglobin level, age, cell differentiation, and pelvic lymph node status with treatment failure were evaluated. The independent prognostic factors were identified by multivariate analysis. The study group was further stratified into subgroups using combinations of these risk factors. Results: In the study group, independent risk factors for local relapse were advanced stage and age 2, and positive pelvic lymph nodes. The 5-year distant relapse-free survival rate was 83% for patients with bulky Stage IB-IIA and IIB disease, SCC-ag level 2, and positive lymph nodes. Conclusion: The risk of treatment failure in advanced-stage cervical cancer patients treated by RT alone can be more precisely predicted by risk stratification. A certain subgroup of patients had better control than the others. The benefit of treating these relatively low-risk patients with additional treatment such as concurrent chemotherapy should be further evaluated in prospective studies or meta-analyses

Risk stratification by the Appendicitis Inflammatory Response score to guide decision-making in patients with suspected appendicitis.

Science.gov (United States)

Scott, A J; Mason, S E; Arunakirinathan, M; Reissis, Y; Kinross, J M; Smith, J J

2015-04-01

Current management of suspected appendicitis is hampered by the overadmission of patients with non-specific abdominal pain and a significant negative exploration rate. The potential benefits of risk stratification by the Appendicitis Inflammatory Response (AIR) score to guide clinical decision-making were assessed. During this 50-week prospective observational study at one institution, the AIR score was calculated for all patients admitted with suspected appendicitis. Appendicitis was diagnosed by histological examination, and patients were classified as having non-appendicitis pain if histological findings were negative or surgery was not performed. The diagnostic performance of the AIR score and the potential for risk stratification to reduce admissions, optimize imaging and prevent unnecessary explorations were quantified. A total of 464 patients were included, of whom 210 (63·3 per cent) with non-appendicitis pain were correctly classified as low risk. However, 13 low-risk patients had appendicitis. Low-risk patients accounted for 48·1 per cent of admissions (223 of 464), 57 per cent of negative explorations (48 of 84) and 50·7 per cent of imaging requests (149 of 294). An AIR score of 5 or more (intermediate and high risk) had high sensitivity for all severities of appendicitis (90 per cent) and also for advanced appendicitis (98 per cent). An AIR score of 9 or more (high risk) was very specific (97 per cent) for appendicitis, and the majority of patients with appendicitis in the high-risk group (21 of 30, 70 per cent) had perforation or gangrene. Ultrasound imaging could not exclude appendicitis in low-risk patients (negative likelihood ratio (LR) 1·0) but could rule-in the diagnosis in intermediate-risk patients (positive LR 10·2). CT could exclude appendicitis in low-risk patients (negative LR 0·0) and rule-in appendicitis in the intermediate group (positive LR 10·9). Risk stratification of patients with suspected appendicitis by the AIR score could

Chronic Obstructive Pulmonary Disease heterogeneity: challenges for health risk assessment, stratification and management.

Science.gov (United States)

Roca, Josep; Vargas, Claudia; Cano, Isaac; Selivanov, Vitaly; Barreiro, Esther; Maier, Dieter; Falciani, Francesco; Wagner, Peter; Cascante, Marta; Garcia-Aymerich, Judith; Kalko, Susana; De Mas, Igor; Tegnér, Jesper; Escarrabill, Joan; Agustí, Alvar; Gomez-Cabrero, David

2014-11-28

Heterogeneity in clinical manifestations and disease progression in Chronic Obstructive Pulmonary Disease (COPD) lead to consequences for patient health risk assessment, stratification and management. Implicit with the classical "spill over" hypothesis is that COPD heterogeneity is driven by the pulmonary events of the disease. Alternatively, we hypothesized that COPD heterogeneities result from the interplay of mechanisms governing three conceptually different phenomena: 1) pulmonary disease, 2) systemic effects of COPD and 3) co-morbidity clustering, each of them with their own dynamics. To explore the potential of a systems analysis of COPD heterogeneity focused on skeletal muscle dysfunction and on co-morbidity clustering aiming at generating predictive modeling with impact on patient management. To this end, strategies combining deterministic modeling and network medicine analyses of the Biobridge dataset were used to investigate the mechanisms of skeletal muscle dysfunction. An independent data driven analysis of co-morbidity clustering examining associated genes and pathways was performed using a large dataset (ICD9-CM data from Medicare, 13 million people). Finally, a targeted network analysis using the outcomes of the two approaches (skeletal muscle dysfunction and co-morbidity clustering) explored shared pathways between these phenomena. (1) Evidence of abnormal regulation of skeletal muscle bioenergetics and skeletal muscle remodeling showing a significant association with nitroso-redox disequilibrium was observed in COPD; (2) COPD patients presented higher risk for co-morbidity clustering than non-COPD patients increasing with ageing; and, (3) the on-going targeted network analyses suggests shared pathways between skeletal muscle dysfunction and co-morbidity clustering. The results indicate the high potential of a systems approach to address COPD heterogeneity. Significant knowledge gaps were identified that are relevant to shape strategies aiming at

Noninvasive Computed Tomography-based Risk Stratification of Lung Adenocarcinomas in the National Lung Screening Trial.

Science.gov (United States)

Maldonado, Fabien; Duan, Fenghai; Raghunath, Sushravya M; Rajagopalan, Srinivasan; Karwoski, Ronald A; Garg, Kavita; Greco, Erin; Nath, Hrudaya; Robb, Richard A; Bartholmai, Brian J; Peikert, Tobias

2015-09-15

Screening for lung cancer using low-dose computed tomography (CT) reduces lung cancer mortality. However, in addition to a high rate of benign nodules, lung cancer screening detects a large number of indolent cancers that generally belong to the adenocarcinoma spectrum. Individualized management of screen-detected adenocarcinomas would be facilitated by noninvasive risk stratification. To validate that Computer-Aided Nodule Assessment and Risk Yield (CANARY), a novel image analysis software, successfully risk stratifies screen-detected lung adenocarcinomas based on clinical disease outcomes. We identified retrospective 294 eligible patients diagnosed with lung adenocarcinoma spectrum lesions in the low-dose CT arm of the National Lung Screening Trial. The last low-dose CT scan before the diagnosis of lung adenocarcinoma was analyzed using CANARY blinded to clinical data. Based on their parametric CANARY signatures, all the lung adenocarcinoma nodules were risk stratified into three groups. CANARY risk groups were compared using survival analysis for progression-free survival. A total of 294 patients were included in the analysis. Kaplan-Meier analysis of all the 294 adenocarcinoma nodules stratified into the Good, Intermediate, and Poor CANARY risk groups yielded distinct progression-free survival curves (P < 0.0001). This observation was confirmed in the unadjusted and adjusted (age, sex, race, and smoking status) progression-free survival analysis of all stage I cases. CANARY allows the noninvasive risk stratification of lung adenocarcinomas into three groups with distinct post-treatment progression-free survival. Our results suggest that CANARY could ultimately facilitate individualized management of incidentally or screen-detected lung adenocarcinomas.

Prediction of breast cancer risk based on profiling with common genetic variants

DEFF Research Database (Denmark)

Mavaddat, Nasim; Pharoah, Paul D P; Michailidou, Kyriaki

2015-01-01

BACKGROUND: Data for multiple common susceptibility alleles for breast cancer may be combined to identify women at different levels of breast cancer risk. Such stratification could guide preventive and screening strategies. However, empirical evidence for genetic risk stratification is lacking. M...

Prediction of breast cancer risk based on profiling with common genetic variants

NARCIS (Netherlands)

N. Mavaddat (Nasim); P.D.P. Pharoah (Paul); K. Michailidou (Kyriaki); J.P. Tyrer (Jonathan); M.N. Brook (Mark N.); M.K. Bolla (Manjeet); Q. Wang (Qing); J. Dennis (Joe); A.M. Dunning (Alison); M. Shah (Mitul); R.N. Luben (Robert); J. Brown (Judith); S.E. Bojesen (Stig); B.G. Nordestgaard (Børge); S.F. Nielsen (Sune F.); H. Flyger (Henrik); K. Czene (Kamila); H. Darabi (Hatef); M. Eriksson (Mikael); J. Peto (Julian); I. dos Santos Silva (Isabel); F. Dudbridge (Frank); N. Johnson (Nichola); M.K. Schmidt (Marjanka); A. Broeks (Annegien); S. Verhoef; E.J. Rutgers (Emiel J.); A.J. Swerdlow (Anthony ); A. Ashworth (Alan); N. Orr (Nick); M. Schoemaker (Minouk); J.D. Figueroa (Jonine); S.J. Chanock (Stephen); L.A. Brinton (Louise); J. Lissowska (Jolanta); F.J. Couch (Fergus); J.E. Olson (Janet); C. Vachon (Celine); V.S. Pankratz (Shane); D. Lambrechts (Diether); H. Wildiers (Hans); C. van Ongeval (Chantal); E. van Limbergen (Erik); V. Kristensen (Vessela); G. Grenaker Alnæs (Grethe); S. Nord (Silje); A.-L. Borresen-Dale (Anne-Lise); H. Nevanlinna (Heli); T.A. Muranen (Taru); K. Aittomäki (Kristiina); C. Blomqvist (Carl); J. Chang-Claude (Jenny); A. Rudolph (Anja); P. Seibold (Petra); D. Flesch-Janys (Dieter); P.A. Fasching (Peter); L. Haeberle (Lothar); A.B. Ekici (Arif); M.W. Beckmann (Matthias); B. Burwinkel (Barbara); F. Marme (Federick); A. Schneeweiss (Andreas); C. Sohn (Christof); A. Trentham-Dietz (Amy); P. Newcomb (Polly); L. Titus (Linda); K.M. Egan (Kathleen M.); D. Hunter (David); S. Lindstrom (Stephen); R. Tamimi (Rulla); P. Kraft (Peter); N. Rahman (Nazneen); C. Turnbull (Clare); A. Renwick (Anthony); S. Seal (Sheila); J. Li (Jingmei); J. Liu (Jianjun); M.K. Humphreys (Manjeet); J. Benítez (Javier); M.P. Zamora (Pilar); J.I. Arias Pérez (José Ignacio); P. Menéndez (Primitiva); A. Jakubowska (Anna); J. Lubinski (Jan); K. Jaworska-Bieniek (Katarzyna); K. Durda (Katarzyna); N.V. Bogdanova (Natalia); N.N. Antonenkova (Natalia); T. Dörk (Thilo); H. Anton-Culver (Hoda); S.L. Neuhausen (Susan); A. Ziogas (Argyrios); L. Bernstein (Leslie); P. Devilee (Peter); R.A.E.M. Tollenaar (Rob); C.M. Seynaeve (Caroline); C.J. van Asperen (Christi); A. Cox (Angela); S.S. Cross (Simon); M.W.R. Reed (Malcolm); E.K. Khusnutdinova (Elza); M. Bermisheva (Marina); D. Prokofyeva (Darya); Z. Takhirova (Zalina); A. Meindl (Alfons); R.K. Schmutzler (Rita); C. Sutter (Christian); R. Yang (Rongxi); P. Schürmann (Peter); M. Bremer (Michael); H. Christiansen (Hans); T.-W. Park-Simon; P. Hillemanns (Peter); P. Guénel (Pascal); T. Truong (Thérèse); F. Menegaux (Florence); M. Sanchez (Marie); P. Radice (Paolo); P. Peterlongo (Paolo); S. Manoukian (Siranoush); V. Pensotti (Valeria); J. Hopper (John); H. Tsimiklis (Helen); C. Apicella (Carmel); M.C. Southey (Melissa); H. Brauch (Hiltrud); T. Brüning (Thomas); Y.-D. Ko (Yon-Dschun); A.J. Sigurdson (Alice); M.M. Doody (Michele M.); U. Hamann (Ute); D. Torres (Diana); H.U. Ulmer (Hans); A. Försti (Asta); E.J. Sawyer (Elinor); I.P. Tomlinson (Ian); M. Kerin (Michael); N. Miller (Nicola); I.L. Andrulis (Irene); J.A. Knight (Julia); G. Glendon (Gord); A. Marie Mulligan (Anna); G. Chenevix-Trench (Georgia); R. Balleine (Rosemary); G.G. Giles (Graham); R.L. Milne (Roger); C.A. McLean (Catriona Ann); A. Lindblom (Annika); S. Margolin (Sara); C.A. Haiman (Christopher); B.E. Henderson (Brian); F. Schumacher (Fredrick); L. Le Marchand (Loic); U. Eilber (Ursula); S. Wang-Gohrke (Shan); M.J. Hooning (Maartje); A. Hollestelle (Antoinette); A.M.W. van den Ouweland (Ans); L.B. Koppert (Lisa); J. Carpenter (Jane); C. Clarke (Christine); R.J. Scott (Rodney J.); A. Mannermaa (Arto); V. Kataja (Vesa); V-M. Kosma (Veli-Matti); J.M. Hartikainen (J.); H. Brenner (Hermann); V. Arndt (Volker); C. Stegmaier (Christa); A. Karina Dieffenbach (Aida); R. Winqvist (Robert); K. Pykäs (Katri); A. Jukkola-Vuorinen (Arja); M. Grip (Mervi); K. Offit (Kenneth); J. Vijai (Joseph); M. Robson (Mark); R. Rau-Murthy (Rohini); M. Dwek (Miriam); R. Swann (Ruth); K. Annie Perkins (Katherine); M.S. Goldberg (Mark); F. Labrèche (France); M. Dumont (Martine); D. Eccles (Diana); W. Tapper (William); M. Rafiq (Meena); E.M. John (Esther M.); A.S. Whittemore (Alice); S. Slager (Susan); D. Yannoukakos (Drakoulis); A.E. Toland (Amanda); S. Yao (Song); W. Zheng (Wei); S.L. Halverson (Sandra L.); A. González-Neira (Anna); G. Pita (Guillermo); M. Rosario Alonso; N. Álvarez (Nuria); D. Herrero (Daniel); D.C. Tessier (Daniel C.); D. Vincent (Daniel); F. Bacot (Francois); C. Luccarini (Craig); C. Baynes (Caroline); S. Ahmed (Shahana); M. Maranian (Melanie); S. Healey (Sue); J. Simard (Jacques); P. Hall (Per); D.F. Easton (Douglas); M. García-Closas (Montserrat)

2015-01-01

textabstractBackground: Data for multiple common susceptibility alleles for breast cancer may be combined to identify women at different levels of breast cancer risk. Such stratification could guide preventive and screening strategies. However, empirical evidence for genetic risk stratification is

Segmented Symbolic Dynamics for Risk Stratification in Patients with Ischemic Heart Failure, Cardiovascular Engineering and Technology

OpenAIRE

Voss, Andreas; Schroeder, Rico; Caminal Magrans, Pere; Vallverdú Ferrer, Montserrat; Brunel, Helena; Cygankiewicz, I.; Vázquez, Rafael; Bayes de Luna, Antonio

2010-01-01

Chronic heart failure (CHF) is recognized as major and escalating public health problem. Approximately 69% of CHF patients suffer from cardiac death within 5 years after the initial diagnosis. Until now, no generally accepted ECG risk predictors in CHF patients are available. The objective of this study was to investigate the suitability of the new developed non-linear method segmented symbolic dynamics (SSD) for risk stratification in patients with ischemic cardiomyop...

Lagged segmented Poincaré plot analysis for risk stratification in patients with dilated cardiomyopathy.

Science.gov (United States)

Voss, Andreas; Fischer, Claudia; Schroeder, Rico; Figulla, Hans R; Goernig, Matthias

2012-07-01

The objectives of this study were to introduce a new type of heart-rate variability analysis improving risk stratification in patients with idiopathic dilated cardiomyopathy (DCM) and to provide additional information about impaired heart beat generation in these patients. Beat-to-beat intervals (BBI) of 30-min ECGs recorded from 91 DCM patients and 21 healthy subjects were analyzed applying the lagged segmented Poincaré plot analysis (LSPPA) method. LSPPA includes the Poincaré plot reconstruction with lags of 1-100, rotating the cloud of points, its normalized segmentation adapted to their standard deviations, and finally, a frequency-dependent clustering. The lags were combined into eight different clusters representing specific frequency bands within 0.012-1.153 Hz. Statistical differences between low- and high-risk DCM could be found within the clusters II-VIII (e.g., cluster IV: 0.033-0.038 Hz; p = 0.0002; sensitivity = 85.7 %; specificity = 71.4 %). The multivariate statistics led to a sensitivity of 92.9 %, specificity of 85.7 % and an area under the curve of 92.1 % discriminating these patient groups. We introduced the LSPPA method to investigate time correlations in BBI time series. We found that LSPPA contributes considerably to risk stratification in DCM and yields the highest discriminant power in the low and very low-frequency bands.

[Syncope and work: role of the occupational physician and global risk stratification].

Science.gov (United States)

Barbic, F; Angaroni, L; Orlandi, M; Costantino, G; Dipaola, E; Borleri, D; Borchini, R; D'Adda, F; Perego, F; Borella, M; Galli, A; Solbiati, M; Scanella, E; Casazza, G; Seghizzi, P; Furlan, R

2011-01-01

Safety risk for subjects suffering from syncope while working has not been as yet addressed by occupational medicine. The present study was aimed at evaluating a new developed methodology for job tasks risk stratification in patients with syncope. During a work-shop on syncope and occupational risk, 149 occupational physicians (OP) with about 10 years of clinical experience were asked to fulfil a Visual Analogue Scale (VAS) concerning the doctor's estimated potential damage (D) to the worker and the probability of a damage to occur (P) should syncope take place during the job task. Five job tasks characterized by different risk for safety (1, driving; 2, toxic products handling; 3, job performed closed to hot surfaces o free flames; 4, surgical activity; 5, office job) were identified. OP correctly stratified the risk associated to the different job tasks in patients with syncope. Unexpectedly, task #3 was given a risk similar to that obtained in drivers. This might be of paramount clinical and social importance when patients with syncope have to return to their job tasks.

Characteristic and Preferences of Green Consumer Stratification As Bases to Formulating Marketing Strategies of Ecolabel-Certified Furniture

OpenAIRE

Ririn Wulandari; Budi Suharjo; Agus W. Soehadi; Herry Purnomo

2012-01-01

International furniture markets certify ecolabel has been growing, but the domestic market has not yet developed. Unfortunate, because these products have two advantages that ensure environmental sustainability and promote a furniture market. This study was expected to open and developed the domestic market for ecolabel-certified furniture. The aim of this study was to develop marketing strategies for ecolabel-certified furniture on each of green consumer stratifications. Consumer stratificat...

The value of exercise radionuclide ventriculography in risk stratification after coronary arterial bypass grafting

International Nuclear Information System (INIS)

Iskandrian, A.S.; Hakki, A.H.; Goel, I.P.; Mundth, E.D.; Kane, S.; Schenk, C.

1985-01-01

Cardiac events after coronary artery bypass surgery (CABG) may be related to left ventricular (LV) function, residual coronary artery diseases (CAD), graft occlusion, and progression of CAD. This study examined the value of rest and exercise (EX) radionuclide ventriculography (RNV) done 3-6 mos after CABG in risk stratification in 212 pts. There were 185 men and 27 women, aged 57 +- 8 years (mean +- SD). During a followup period of up to 4 years, (15 +- 10 months), there were 23 cardiac events; 13 pts died of cardiac causes and 20 had non-fatal acute myocardial infarctions. The pts with and without events did not differ in: clinical presentation after CABG (most were asymptomatic), medications and ECG findings at rest and EX. The pts with events had lower EX systolic blood pressure (p < 0.01); resting LV ejection fraction (EF) (p = 0.002), and EX EF (40 +- 18% vs 54 +- 16%, p = 0.002). The change in EF (rest to EX) was not significantly different (l.6 +- 8.2%, vs 2.1 +- 9.2%). Survival analysis (Cox model) identified the EX EF as the best predictor of death and total events (X/sup 2/ = 4.3 and 2.4, p = 0.04 and 0.07 respectively). Actuarial life table analysis showed that the risk increased as the EX EF decreased when pts were grouped into EX EF ≥ 50, 30-49, and <30%, (p < 0.001, Mantel-Cox). Thus, EX RNA is useful in risk stratification after CABG. The EX LVEF is an important descriptor that categorizes pts into different risks groups. The pts at high risk probably require more aggressive followup and continued medical therapy

Noninvasive Computed Tomography–based Risk Stratification of Lung Adenocarcinomas in the National Lung Screening Trial

Science.gov (United States)

Maldonado, Fabien; Duan, Fenghai; Raghunath, Sushravya M.; Rajagopalan, Srinivasan; Karwoski, Ronald A.; Garg, Kavita; Greco, Erin; Nath, Hrudaya; Robb, Richard A.; Bartholmai, Brian J.

2015-01-01

Rationale: Screening for lung cancer using low-dose computed tomography (CT) reduces lung cancer mortality. However, in addition to a high rate of benign nodules, lung cancer screening detects a large number of indolent cancers that generally belong to the adenocarcinoma spectrum. Individualized management of screen-detected adenocarcinomas would be facilitated by noninvasive risk stratification. Objectives: To validate that Computer-Aided Nodule Assessment and Risk Yield (CANARY), a novel image analysis software, successfully risk stratifies screen-detected lung adenocarcinomas based on clinical disease outcomes. Methods: We identified retrospective 294 eligible patients diagnosed with lung adenocarcinoma spectrum lesions in the low-dose CT arm of the National Lung Screening Trial. The last low-dose CT scan before the diagnosis of lung adenocarcinoma was analyzed using CANARY blinded to clinical data. Based on their parametric CANARY signatures, all the lung adenocarcinoma nodules were risk stratified into three groups. CANARY risk groups were compared using survival analysis for progression-free survival. Measurements and Main Results: A total of 294 patients were included in the analysis. Kaplan-Meier analysis of all the 294 adenocarcinoma nodules stratified into the Good, Intermediate, and Poor CANARY risk groups yielded distinct progression-free survival curves (P < 0.0001). This observation was confirmed in the unadjusted and adjusted (age, sex, race, and smoking status) progression-free survival analysis of all stage I cases. Conclusions: CANARY allows the noninvasive risk stratification of lung adenocarcinomas into three groups with distinct post-treatment progression-free survival. Our results suggest that CANARY could ultimately facilitate individualized management of incidentally or screen-detected lung adenocarcinomas. PMID:26052977

Hepatitis B virus reactivation during immunosuppressive therapy: Appropriate risk stratification.

Science.gov (United States)

Seto, Wai-Kay

2015-04-28

Our understanding of hepatitis B virus (HBV) reactivation during immunosuppresive therapy has increased remarkably during recent years. HBV reactivation in hepatitis B surface antigen (HBsAg)-positive individuals has been well-described in certain immunosuppressive regimens, including therapies containing corticosteroids, anthracyclines, rituximab, antibody to tumor necrosis factor (anti-TNF) and hematopoietic stem cell transplantation (HSCT). HBV reactivation could also occur in HBsAg-negative, antibody to hepatitis B core antigen (anti-HBc) positive individuals during therapies containing rituximab, anti-TNF or HSCT.For HBsAg-positive patients, prophylactic antiviral therapy is proven to the effective in preventing HBV reactivation. Recent evidence also demonstrated entecavir to be more effective than lamivudine in this aspect. For HBsAg-negative, anti-HBc positive individuals, the risk of reactivations differs with the type of immunosuppression. For rituximab, a prospective study demonstrated the 2-year cumulative risk of reactivation to be 41.5%, but prospective data is still lacking for other immunosupressive regimes. The optimal management in preventing HBV reactivation would involve appropriate risk stratification for different immunosuppressive regimes in both HBsAg-positive and HBsAg-negative, anti-HBc positive individuals.

Power of resting echocardiographic measurements to classify pulmonary hypertension patients according to European society of cardiology exercise testing risk stratification cut-offs.

Science.gov (United States)

Rehman, Michaela B; Garcia, Rodrigue; Christiaens, Luc; Larrieu-Ardilouze, Elisa; Howard, Luke S; Nihoyannopoulos, Petros

2018-04-15

Right ventricular function is the major determinant of morbidity and mortality in pulmonary arterial hypertension (PAH). The ESC risk assessment strategy for PAH is based on clinical status, exercise testing, NTproBNP, imaging and haemodynamics but does not include right ventricular function. Our aims were to test the power of resting echocardiographic measurements to classify PAH patients according to ESC exercise testing risk stratification cut-offs and to determine if the classification power of echocardiographic parameters varied in chronic thrombo-embolic pulmonary hypertension (CTEPH). We prospectively and consecutively recruited 46 PAH patients and 42 CTEPH patients referred for cardio-pulmonary exercise testing and comprehensive transthoracic echocardiography. Exercise testing parameters analyzed were peak oxygen consumption, percentage of predicted maximal oxygen consumption and the slope of ventilation against carbon dioxide production. Receiver operator characteristic curves were used to determine the optimal diagnostic cut-off values of echocardiographic parameters for classifying the patients in intermediate or high risk category according to exercise testing. Measurements of right ventricular systolic function were the best for classifying in PAH (area under the curve 0.815 to 0.935). Measurements of right ventricular pressure overload (0.810 to 0.909) were optimal for classifying according to exercise testing in CTEPH. Measurements of left ventricular function were of no use in either group. Measurements of right ventricular systolic function can classify according to exercise testing risk stratification cut-offs in PAH. However, this is not the case in CTEPH where pressure overload, rather than right ventricular function seems to be linked to exercise performance. Copyright © 2018 Elsevier B.V. All rights reserved.

The incremental value of brachial flow-mediated dilation measurements in risk stratification for incident cardiovascular events: a systematic review.

Science.gov (United States)

Peters, Sanne A E; den Ruijter, Hester M; Bots, Michiel L

2012-06-01

Abstract Adequate risk assessment for cardiovascular disease (CVD) is essential as a guide to initiate drug treatment. Current methods based on traditional risk factors could be improved considerably. Although brachial flow-mediated dilation (FMD) predicts subsequent cardiovascular events, its predictive value on top of traditional risk factors is unknown. We performed a systematic review to evaluate the incremental predictive value of FMD on top of traditional risk factors in asymptomatic individuals. Using PubMed and reference tracking, three studies were identified that reported on the incremental value of FMD using change in the area under the curve (AUC). Two large cohort studies found no improvement in AUC when FMD was added to traditional risk prediction models, whereas one small case-control study found an improvement. One study used the net reclassification improvement (NRI) to assess whether FMD measurement leads to correct risk stratification in risk categories. Although this study did not find an improvement in AUC, the NRI was statistically significant. Based on the reclassification results of this study, FMD measurement might be helpful in risk prediction. Evidence supporting the use of FMD measurement in clinical practice for risk stratification for CVD on top of traditional risk factors is limited, and future studies are needed.

Risk stratification by using non-invasive radionuclide imaging in patients with unstable angina spec tories

International Nuclear Information System (INIS)

Saghari, M.

2002-01-01

Unstable angina represents a heterogeneous spectrum of clinical entities between chronic stable angina and acute myocardial infraction. Acute ischemic syndromes (including unstable angina) result from abrupt reduction in coronary flow, frequently after atherosclerotic plaque disruption and with or without associated thrombosis or vasospasm. Nuclear cardiology studies and in particular, myocardial perfusion imaging are powerful noninvasive tools for detecting and assessing the severity of acute ischemic syndromes, including unstable angina pec tories. The information derived from a nuclear cardiology study can answer unresolved clinical question and aid in subsequent patient management, specifically jeopardized myocardium detected during spontaneously occurring acute chest pain or controlled stress testing are important determinant of: 1) The need for admission to an intensive care monitoring unit 2) The need for and urgency of coronary angiography 3) The appropriate use of percutaneous or surgical coronary revascularization procedures. Extensive information suggests the stress nuclear perfusion imaging is the best validated technique for predischarge risk stratification with unstable angina patients who have been medically stabilized. Early information suggests avoidance of unecessary coronary angiography or revascularization is the cost effective strategy

Noninvasive non Doses Method for Risk Stratification of Breast Diseases

Directory of Open Access Journals (Sweden)

I. A. Apollonova

2014-01-01

Full Text Available The article concerns a relevant issue that is a development of noninvasive method for screening diagnostics and risk stratification of breast diseases. The developed method and its embodiment use both the analysis of onco-epidemiologic tests and the iridoglyphical research.Widely used onco-epidemiologic tests only reflect the patient’s subjective perception of her own life history and sickness. Therefore to confirm the revealed factors, modern objective and safe methods are necessary.Iridoglyphical research may be considered as one of those methods, since it allows us to reveal changes in iris’ zones in real time. As these zones are functionally linked with intern organs and systems, in this case mammary glands, changes of iris’ zones may be used to assess risk groups for mammary gland disorders.The article presents results of research conducted using a prototype of the hardwaresoftware complex to provide screening diagnostics and risk stratification of mammary gland disorders.Research has been conducted using verified materials, provided by the Biomedical Engineering Faculty and the Scientific Biometry Research and Development Centre of Bauman Moscow State Technical University, the City of Moscow’s GUZ Clinical and Diagnostic Centre N°4 of the Western Administrative District and the First Mammology (Breast Care Centre of the Russian Federation’s Ministry of Health and Social Development.The information, obtained as a result of onco-epidemiological tests and iridoglyphical research, was used to develop a procedure of quantitative diagnostics aimed to assess mammary gland cancer risk groups. The procedure is based on Bayes conditional probability.The task of quantitative diagnostics may be formally divided into the differential assessment of three states. The first, D1, is the norm, which corresponds to the population group with a lack of risk factors or changes of the mammary glands. The second, D2, is the population group

BRAIN NATRIURETIC PEPTIDE (BNP: BIOMARKER FOR RISK STRATIFICATION AND FUNCTIONAL RECOVERY PREDICTION IN ISCHEMIC STROKE

Directory of Open Access Journals (Sweden)

STANESCU Ioana

2015-02-01

Full Text Available Functional outcome after cardiovascular and cerebrovascular events is traditionally predicted using demographic and clinical variables like age, gender, blood pressure, cholesterol levels, diabetes status, smoking habits or pre-existing morbidity. Identification of new variables will improve the risk stratification of specific categories of patients. Numerous blood-based biomarkers associated with increased cardiovascular risk have been identified; some of them even predict cardiovascular events. Investigators have tried to produce prediction models by incorporating traditional risk factors and biomarkers. (1. Widely-available, rapidly processed and less expensive biomarkers could be used in the future to guide management of complex cerebrovascular patients in order to maximize their recovery (2 Recently, studies have demonstrated that biomarkers can predict not only the risk for a specific clinical event, but also the risk of death of vascular cause and the functional outcome after cardiovascular or cerebrovascular events. Early prediction of fatal outcome after stroke may improve therapeutic strategies (such as the use of more aggressive treatments or inclusion of patients in clinical trials and guide decision-making processes in order to maximize patient’s chances for survival and recovery. (3 Long term functional outcome after stroke is one of the most difficult variables to predict. Elevated serum levels of brain natriuretic peptide (BNP are powerful predictor of outcomes in patients with cardiovascular disease (heart failure, atrial fibrillation. Potential role of BNP in predicting atrial fibrillation occurrence, cardio-embolic stroke and post-stroke mortality have been proved in many studies. However, data concerning the potential role of BNP in predicting short term and long term functional outcomes after stroke remain controversial.

Acute myeloid leukemia in the era of precision medicine: recent advances in diagnostic classification and risk stratification.

Science.gov (United States)

Kansal, Rina

2016-03-01

Acute myeloid leukemia (AML) is a genetically heterogeneous myeloid malignancy that occurs more commonly in adults, and has an increasing incidence, most likely due to increasing age. Precise diagnostic classification of AML requires clinical and pathologic information, the latter including morphologic, immunophenotypic, cytogenetic and molecular genetic analysis. Risk stratification in AML requires cytogenetics evaluation as the most important predictor, with genetic mutations providing additional necessary information. AML with normal cytogenetics comprises about 40%-50% of all AML, and has been intensively investigated. The currently used 2008 World Health Organization classification of hematopoietic neoplasms has been proposed to be updated in 2016, also to include an update on the classification of AML, due to the continuously increasing application of genomic techniques that have led to major advances in our knowledge of the pathogenesis of AML. The purpose of this review is to describe some of these recent major advances in the diagnostic classification and risk stratification of AML.

Acute myeloid leukemia in the era of precision medicine: recent advances in diagnostic classification and risk stratification

International Nuclear Information System (INIS)

Kansal, Rina

2016-01-01

Acute myeloid leukemia (AML) is a genetically heterogeneous myeloid malignancy that occurs more commonly in adults, and has an increasing incidence, most likely due to increasing age. Precise diagnostic classification of AML requires clinical and pathologic information, the latter including morphologic, immunophenotypic, cytogenetic and molecular genetic analysis. Risk stratification in AML requires cytogenetics evaluation as the most important predictor, with genetic mutations providing additional necessary information. AML with normal cytogenetics comprises about 40%-50% of all AML, and has been intensively investigated. The currently used 2008 World Health Organization classification of hematopoietic neoplasms has been proposed to be updated in 2016, also to include an update on the classification of AML, due to the continuously increasing application of genomic techniques that have led to major advances in our knowledge of the pathogenesis of AML. The purpose of this review is to describe some of these recent major advances in the diagnostic classification and risk stratification of AML

Risk Stratification for Athletes and Adventurers in High-Altitude Environments: Recommendations for Preparticipation Evaluation.

Science.gov (United States)

Campbell, Aaron D; McIntosh, Scott E; Nyberg, Andy; Powell, Amy P; Schoene, Robert B; Hackett, Peter

2015-12-01

High-altitude athletes and adventurers face a number of environmental and medical risks. Clinicians often advise participants or guiding agencies before or during these experiences. Preparticipation evaluation (PPE) has the potential to reduce risk of high-altitude illnesses in athletes and adventurers. Specific conditions susceptible to high-altitude exacerbation also important to evaluate include cardiovascular and lung diseases. Recommendations by which to counsel individuals before participation in altitude sports and adventures are few and of limited focus. We reviewed the literature, collected expert opinion, and augmented principles of a traditional sport PPE to accommodate the high-altitude wilderness athlete/adventurer. We present our findings with specific recommendations on risk stratification during a PPE for the high-altitude athlete/adventurer. Copyright © 2015. Published by Elsevier Inc.

Value of Exercise ECG for Risk Stratification in Suspected or Known CAD in the Era of Advanced Imaging Technologies.

Science.gov (United States)

Bourque, Jamieson M; Beller, George A

2015-11-01

Exercise stress electrocardiography (ExECG) is underutilized as the initial test modality in patients with interpretable electrocardiograms who are able to exercise. Although stress myocardial imaging techniques provide valuable diagnostic and prognostic information, variables derived from ExECG can yield substantial data for risk stratification, either supplementary to imaging variables or without concurrent imaging. In addition to exercise-induced ischemic ST-segment depression, such markers as ST-segment elevation in lead aVR, abnormal heart rate recovery post-exercise, failure to achieve target heart rate, and poor exercise capacity improve risk stratification of ExECG. For example, patients achieving ≥10 metabolic equivalents on ExECG have a very low prevalence of inducible ischemia and an excellent prognosis. In contrast, cardiac imaging techniques add diagnostic and prognostic value in higher-risk populations (e.g., poor functional capacity, diabetes, or chronic kidney disease). Optimal test selection for symptomatic patients with suspected coronary artery disease requires a patient-centered approach factoring in the risk/benefit ratio and cost-effectiveness. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Cold stratification, but not stratification in salinity, enhances seedling ...

African Journals Online (AJOL)

Cold stratification, but not stratification in salinity, enhances seedling growth of wheat under salt treatment. L Wang, HL Wang, CH Yin, CY Tian. Abstract. Cold stratification was reported to release seed dormancy and enhance plant tolerance to salt stress. Experiments were conducted to test the hypothesis that cold ...

Risk stratification and detection of new colorectal neoplasms after colorectal cancer screening with faecal occult blood test

DEFF Research Database (Denmark)

Bjerrum, Andreas; Milter, Maya Christel; Andersen, Ole

2015-01-01

BACKGROUND: Limited data exist on adenoma surveillance as recommended in the European guidelines for quality assurance in colorectal cancer (CRC) screening and diagnosis after faecal occult blood test (FOBT) screening. OBJECTIVE: To assess the European guidelines for adenoma surveillance after CRC...... of CRC was higher in risk group C than A (RR 5.20, 95% confidence interval: 0.63-42.58), but not statistically significant. In risk group C, half of new advanced adenomas were detected within the first year and four of nine CRC were detected within 3 years. CONCLUSION: Risk stratification of adenoma...

Application of Multivariate Probabilistic (Bayesian) Networks to Substance Use Disorder Risk Stratification and Cost Estimation

OpenAIRE

Weinstein, Lawrence; Radano, Todd A; Jack, Timothy; Kalina, Philip; Eberhardt, John S

2009-01-01

Introduction: This paper explores the use of machine learning and Bayesian classification models to develop broadly applicable risk stratification models to guide disease management of health plan enrollees with substance use disorder (SUD). While the high costs and morbidities associated with SUD are understood by payers, who manage it through utilization review, acute interventions, coverage and cost limitations, and disease management, the literature shows mixed results for these modalitie...

Treatment of unresectable hepatocellular carcinoma with intrahepatic yttrium 90 microspheres: a risk-stratification analysis.

Science.gov (United States)

Goin, James E; Salem, Riad; Carr, Brian I; Dancey, Janet E; Soulen, Michael C; Geschwind, Jean-Francois H; Goin, Kathleen; Van Buskirk, Mark; Thurston, Kenneth

2005-02-01

To present the findings of a risk-stratification survival analysis with use of data collected on a heterogeneous group of patients with hepatocellular carcinoma (HCC) treated with TheraSphere. Baseline, treatment, and follow-up data were collected and analyzed from 121 TheraSphere-treated patients. Survival analyses were performed to identify those variables most strongly associated with 3-month mortality. The presence of any of the identified risk variables resulted in the assignment of a patient to the high-risk category. Five liver reserve and two non-liver reserve variables were identified and used to stratify patients into low- or high-risk groups. Sixteen of the 33 patients assigned to the high-risk group (49%) did not survive the first 3 months after treatment, compared with six of the 88 patients assigned to the low-risk group (7%; Fisher exact test, P TheraSpheres should be evaluated for the presence of the risk variables described herein. The absence of these variables is predictive of improved survival (median of 466 days) compared with patients at high risk (median of 108 days).

Application of cardiovascular disease risk prediction models and the relevance of novel biomarkers to risk stratification in Asian Indians.

Science.gov (United States)

Kanjilal, S; Rao, V S; Mukherjee, M; Natesha, B K; Renuka, K S; Sibi, K; Iyengar, S S; Kakkar, Vijay V

2008-01-01

The increasing pressure on health resources has led to the emergence of risk assessment as an essential tool in the management of cardiovascular disease (CVD). Concern exists regarding the validity of their generalization to all populations. Existing risk scoring models do not incorporate emerging 'novel' risk factors. In this context, the aim of the study was to examine the relevance of British, European, and Framingham predictive CVD risk scores to the asymptomatic high risk Indian population. Blood samples drawn from the participants were analyzed for various 'traditional' and 'novel' biomarkers, and their CVD risk factor profiling was also done. The Framingham model defined only 5% of the study cohort to be at high risk, which appears to be an underestimation of CVD risk in this genetically predisposed population. These subjects at high risk had significantly elevated levels of lipid, pro-inflammatory, pro-thrombotic, and serological markers. It is more relevant to develop risk predictive scores for application to the Indian population. This study substantiates the argument that alternative approaches to risk stratification are required in order to make them more adaptable and applicable to different populations with varying risk factor and disease patterns.

Scores for post-myocardial infarction risk stratification in the community.

Science.gov (United States)

Singh, Mandeep; Reeder, Guy S; Jacobsen, Steven J; Weston, Susan; Killian, Jill; Roger, Véronique L

2002-10-29

Several scores, most of which were derived from clinical trials, have been proposed for stratifying risk after myocardial infarctions (MIs). Little is known about their generalizability to the community, their respective advantages, and whether the ejection fraction (EF) adds prognostic information to the scores. The purpose of this study is to evaluate the Thrombolysis in Myocardial Infarction (TIMI) and Predicting Risk of Death in Cardiac Disease Tool (PREDICT) scores in a geographically defined MI cohort and determine the incremental value of EF for risk stratification. MIs occurring in Olmsted County were validated with the use of standardized criteria and stratified with the ECG into ST-segment elevation (STEMI) and non-ST-segment elevation (NSTEMI) MI. Logistic regression examined the discriminant accuracy of the TIMI and PREDICT scores to predict death and recurrent MI and assessed the incremental value of the EF. After 6.3+/-4.7 years, survival was similar for the 562 STEMIs and 717 NSTEMIs. The discriminant accuracy of the TIMI score was good in STEMI but only fair in NSTEMI. Across time and end points, irrespective of reperfusion therapy, the discriminant accuracy of the PREDICT score was consistently superior to that of the TIMI scores, largely because PREDICT includes comorbidity; EF provided incremental information over that provided by the scores and comorbidity. In the community, comorbidity and EF convey important prognostic information and should be included in approaches for stratifying risk after MI.

Risk stratification of gallbladder polyps (1-2 cm) for surgical intervention with 18F-FDG PET/CT.

Science.gov (United States)

Lee, Jaehoon; Yun, Mijin; Kim, Kyoung-Sik; Lee, Jong-Doo; Kim, Chun K

2012-03-01

We assessed the value of (18)F-FDG uptake in the gallbladder polyp (GP) in risk stratification for surgical intervention and the optimal cutoff level of the parameters derived from GP (18)F-FDG uptake for differentiating malignant from benign etiologies in a select, homogeneous group of patients with 1- to 2-cm GPs. Fifty patients with 1- to 2-cm GPs incidentally found on the CT portion of PET/CT were retrospectively analyzed. All patients had histologic diagnoses. GP (18)F-FDG activity was visually scored positive (≥liver) or negative (L ratio) were also measured. Univariate and multivariate logistic regression analyses were performed to determine the utility of patient and clinical variables--that is, sex, age, gallstone, polyp size, and three (18)F-FDG-related parameters in risk stratification. Twenty GPs were classified as malignant and 30 as benign. Multivariate analyses showed that the age and all parameters (visual criteria, SUVgp, and GP/L) related to (18)F-FDG uptake were significant risk factors, with the GP/L being the most significant. The sex, size of GPs, and presence of concurrent gallstones were found to be insignificant. (18)F-FDG uptake in a GP is a strong risk factor that can be used to determine the necessity of surgical intervention more effectively than other known risk factors. However, all criteria derived from (18)F-FDG uptake presented in this series may be applicable to the assessment of 1- to 2-cm GPs.

Risk stratification and rapid geriatric screening in an emergency department - a quasi-randomised controlled trial.

Science.gov (United States)

Foo, Chik Loon; Siu, Vivan Wing Yin; Ang, Hou; Phuah, Madeline Wei Ling; Ooi, Chee Kheong

2014-08-30

To determine if risk stratification followed by rapid geriatric screening in an emergency department (ED) reduced functional decline, ED reattendance and hospitalisation. This was a quasi-randomised controlled trial. Patients were randomised by the last digit of their national registration identity card (NRIC). Odd number controls received standard ED care; even number patients received geriatric screening, followed by intervention and/or onward referrals. Patients were followed up for 12 months. There were 500 and 280 patients in the control and intervention groups. The intervention group had higher Triage Risk Screening Tool (TRST) scores (34.3% vs 25.4% TRST ≥3, p = 0.01) and lower baseline Instrumental Activity of Daily Living (IADL) scores (22.84 vs 24.18, p fall risk (65.0%), vision (61.4%), and footwear (58.2%). 28.2% were referred to a geriatric clinic and 11.8% were admitted. 425 (85.0%) controls and 234 (83.6%) in the intervention group completed their follow-up. After adjusting for TRST and baseline IADL, the intervention group had significant preservation in function (Basic ADL -0.99 vs -0.24, p geriatric screening at the request of the ED doctor. A major limitation was that a large proportion of patients who were randomized to the intervention group either refused (18.8%) or left the ED before being approached (32.0%). These two groups were not followed up, and hence were excluded in our analysis. Risk stratification and focused geriatric screening in ED resulted in significant preservation of patients' function at 12 months. National Healthcare Group (NHG) Domain Specific Review Board (DSRB) C/09/023. Registered 5th March 2009.

Risk stratification in myelodysplastic syndromes: is there a role for gene expression profiling?

Science.gov (United States)

Zeidan, Amer M; Prebet, Thomas; Saad Aldin, Ehab; Gore, Steven David

2014-04-01

Evaluation of: Pellagatti A, Benner A, Mills KI et al. Identification of gene expression-based prognostic markers in the hematopoietic stem cells of patients with myelodysplastic syndromes. J. Clin. Oncol. 31(28), 3557-3564 (2013). Patients with myelodysplastic syndromes (MDS) exhibit wide heterogeneity in clinical outcomes making accurate risk-stratification an integral part of the risk-adaptive management paradigm. Current prognostic schemes for MDS rely on clinicopathological parameters. Despite the increasing knowledge of the genetic landscape of MDS and the prognostic impact of many newly discovered molecular aberrations, none to date has been incorporated formally into the major risk models. Efforts are ongoing to use data generated from genome-wide high-throughput techniques to improve the 'individualized' outcome prediction for patients. We here discuss an important paper in which gene expression profiling (GEP) technology was applied to marrow CD34(+) cells from 125 MDS patients to generate and validate a standardized GEP-based prognostic signature.

Sudden cardiac arrest in a young patient with hypertrophic cardiomyopathy and zero canonical risk factors: the inherent limitations of risk stratification in hypertrophic cardiomyopathy.

Science.gov (United States)

Kohorst, John J; Bos, J Martijn; Hagler, Donald J; Ackerman, Michael J

2014-01-01

Hypertrophic cardiomyopathy is the most common heritable cardiovascular disease and a common cause of sudden cardiac death (SCD) in young adolescents and athletes. Clinical risk stratification for SCD is predicated on the presence of established risk factors; however, this assessment is far from perfect. Herein, we present a 16-year-old male who was resuscitated successfully from his sentinel event of out-of-hospital cardiac arrest. Prior to this event, he was asymptomatic and lacked all traditional SCD-predisposing risk factors for hypertrophic cardiomyopathy. © 2013 Wiley Periodicals, Inc.

Customized oligonucleotide microarray gene expression-based classification of neuroblastoma patients outperforms current clinical risk stratification.

Science.gov (United States)

Oberthuer, André; Berthold, Frank; Warnat, Patrick; Hero, Barbara; Kahlert, Yvonne; Spitz, Rüdiger; Ernestus, Karen; König, Rainer; Haas, Stefan; Eils, Roland; Schwab, Manfred; Brors, Benedikt; Westermann, Frank; Fischer, Matthias

2006-11-01

To develop a gene expression-based classifier for neuroblastoma patients that reliably predicts courses of the disease. Two hundred fifty-one neuroblastoma specimens were analyzed using a customized oligonucleotide microarray comprising 10,163 probes for transcripts with differential expression in clinical subgroups of the disease. Subsequently, the prediction analysis for microarrays (PAM) was applied to a first set of patients with maximally divergent clinical courses (n = 77). The classification accuracy was estimated by a complete 10-times-repeated 10-fold cross validation, and a 144-gene predictor was constructed from this set. This classifier's predictive power was evaluated in an independent second set (n = 174) by comparing results of the gene expression-based classification with those of risk stratification systems of current trials from Germany, Japan, and the United States. The first set of patients was accurately predicted by PAM (cross-validated accuracy, 99%). Within the second set, the PAM classifier significantly separated cohorts with distinct courses (3-year event-free survival [EFS] 0.86 +/- 0.03 [favorable; n = 115] v 0.52 +/- 0.07 [unfavorable; n = 59] and 3-year overall survival 0.99 +/- 0.01 v 0.84 +/- 0.05; both P model, the PAM predictor classified patients of the second set more accurately than risk stratification of current trials from Germany, Japan, and the United States (P < .001; hazard ratio, 4.756 [95% CI, 2.544 to 8.893]). Integration of gene expression-based class prediction of neuroblastoma patients may improve risk estimation of current neuroblastoma trials.

The emerging role of cardiovascular MRI for risk stratification in hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Hoey, E.T.D.; Teoh, J.K.; Das, I.; Ganeshan, A.; Simpson, H.; Watkin, R.W.

2014-01-01

Hypertrophic cardiomyopathy (HCM) is the most common inheritable cardiovascular disorder. Although many HCM patients remain asymptomatic, sudden death (SD) can occur as the initial manifestation of the disease. It has been hypothesized that myocardial architectural disorganization and scarring represent an unstable electrophysiological substrate that creates susceptibility to malignant ventricular arrhythmias. Cardiovascular magnetic resonance imaging (CMR) is widely used for the diagnosis of HCM, especially in patients with an incomplete or inconclusive echocardiography study. CMR can provide precise non-invasive assessment of biventricular function, wall thickness, and assessment of myocardial fibrosis, using inversion recovery gadolinium-enhanced sequences. CMR is also one of the most promising avenues of research in HCM, and in recent years, has provided many new insights and identified a number of potential adverse prognostic indicators for SD. Future work is still needed to integrate CMR findings into traditional risk assessment algorithms. This paper reviews the evolving role of CMR for risk stratification in HCM including assessment of myocardial hypertrophy, fibrosis and ischaemia

Cold stratification, but not stratification in salinity, enhances seedling ...

African Journals Online (AJOL)

use

2011-10-26

Oct 26, 2011 ... Cold stratification was reported to release seed dormancy and enhance plant tolerance to salt stress. ... Key words: Cold stratification, salt stress, seedling emergence, ... methods used to cope with salinity, seed pre-sowing.

The HAT Score-A Simple Risk Stratification Score for Coagulopathic Bleeding During Adult Extracorporeal Membrane Oxygenation.

Science.gov (United States)

Lonergan, Terence; Herr, Daniel; Kon, Zachary; Menaker, Jay; Rector, Raymond; Tanaka, Kenichi; Mazzeffi, Michael

2017-06-01

The study objective was to create an adult extracorporeal membrane oxygenation (ECMO) coagulopathic bleeding risk score. Secondary analysis was performed on an existing retrospective cohort. Pre-ECMO variables were tested for association with coagulopathic bleeding, and those with the strongest association were included in a multivariable model. Using this model, a risk stratification score was created. The score's utility was validated by comparing bleeding and transfusion rates between score levels. Bleeding also was examined after stratifying by nadir platelet count and overanticoagulation. Predictive power of the score was compared against the risk score for major bleeding during anti-coagulation for atrial fibrillation (HAS-BLED). Tertiary care academic medical center. The study comprised patients who received venoarterial or venovenous ECMO over a 3-year period, excluding those with an identified source of surgical bleeding during exploration. None. Fifty-three (47.3%) of 112 patients experienced coagulopathic bleeding. A 3-variable score-hypertension, age greater than 65, and ECMO type (HAT)-had fair predictive value (area under the receiver operating characteristic curve [AUC] = 0.66) and was superior to HAS-BLED (AUC = 0.64). As the HAT score increased from 0 to 3, bleeding rates also increased as follows: 30.8%, 48.7%, 63.0%, and 71.4%, respectively. Platelet and fresh frozen plasma transfusion tended to increase with the HAT score, but red blood cell transfusion did not. Nadir platelet count less than 50×10 3 /µL and overanticoagulation during ECMO increased the AUC for the model to 0.73, suggesting additive risk. The HAT score may allow for bleeding risk stratification in adult ECMO patients. Future studies in larger cohorts are necessary to confirm these findings. Copyright © 2017 Elsevier Inc. All rights reserved.

INLET STRATIFICATION DEVICE

DEFF Research Database (Denmark)

2006-01-01

An inlet stratification device (5) for a circuit circulating a fluid through a tank (1 ) and for providing and maintaining stratification of the fluid in the tank (1 ). The stratification de- vice (5) is arranged vertically in the tank (1) and comprises an inlet pipe (6) being at least partially...... formed of a flexible porous material and having an inlet (19) and outlets formed of the pores of the porous material. The stratification device (5) further comprises at least one outer pipe (7) surrounding the inlet pipe (6) in spaced relationship thereto and being at least partially formed of a porous...

Effects of Mixture Stratification on Combustion and Emissions of Boosted Controlled Auto-Ignition Engines

Directory of Open Access Journals (Sweden)

Jacek Hunicz

2017-12-01

Full Text Available The stratification of in-cylinder mixtures appears to be an effective method for managing the combustion process in controlled auto-ignition (CAI engines. Stratification can be achieved and controlled using various injection strategies such as split fuel injection and the introduction of a portion of fuel directly before the start of combustion. This study investigates the effect of injection timing and the amount of fuel injected for stratification on the combustion and emissions in CAI engine. The experimental research was performed on a single cylinder engine with direct gasoline injection. CAI combustion was achieved using negative valve overlap and exhaust gas trapping. The experiments were performed at constant engine fueling. Intake boost was applied to control the excess air ratio. The results show that the application of the late injection strategy has a significant effect on the heat release process. In general, the later the injection is and the more fuel is injected for stratification, the earlier the auto-ignition occurs. However, the experimental findings reveal that the effect of stratification on combustion duration is much more complex. Changes in combustion are reflected in NOX emissions. The attainable level of stratification is limited by the excessive emission of unburned hydrocarbons, CO and soot.

Coronary Artery Calcium Screening: Does it Perform Better than Other Cardiovascular Risk Stratification Tools?

Directory of Open Access Journals (Sweden)

Irfan Zeb

2015-03-01

Full Text Available Coronary artery calcium (CAC has been advocated as one of the strongest cardiovascular risk prediction markers. It performs better across a wide range of Framingham risk categories (6%–10% and 10%–20% 10-year risk categories and also helps in reclassifying the risk of these subjects into either higher or lower risk categories based on CAC scores. It also performs better among population subgroups where Framingham risk score does not perform well, especially young subjects, women, family history of premature coronary artery disease and ethnic differences in coronary risk. The absence of CAC is also associated with excellent prognosis, with 10-year event rate of 1%. Studies have also compared with other commonly used markers of cardiovascular disease risk such as Carotid intima-media thickness and highly sensitive C-reactive protein. CAC also performs better compared with carotid intima-media thickness and highly sensitive C-reactive protein in prediction of coronary heart disease and cardiovascular disease events. CAC scans are associated with relatively low radiation exposure (0.9–1.1 mSv and provide information that can be used not only for risk stratification but also can be used to track the progression of atherosclerosis and the effects of statins.

Risk assessment and clinical decision making for colorectal cancer screening.

Science.gov (United States)

Schroy, Paul C; Caron, Sarah E; Sherman, Bonnie J; Heeren, Timothy C; Battaglia, Tracy A

2015-10-01

Shared decision making (SDM) related to test preference has been advocated as a potentially effective strategy for increasing adherence to colorectal cancer (CRC) screening, yet primary care providers (PCPs) are often reluctant to comply with patient preferences if they differ from their own. Risk stratification advanced colorectal neoplasia (ACN) provides a rational strategy for reconciling these differences. To assess the importance of risk stratification in PCP decision making related to test preference for average-risk patients and receptivity to use of an electronic risk assessment tool for ACN to facilitate SDM. Mixed methods, including qualitative key informant interviews and a cross-sectional survey. PCPs at an urban, academic safety-net institution. Screening preferences, factors influencing patient recommendations and receptivity to use of a risk stratification tool. Nine PCPs participated in interviews and 57 completed the survey. Despite an overwhelming preference for colonoscopy by 95% of respondents, patient risk (67%) and patient preferences (63%) were more influential in their decision making than patient comorbidities (31%; P decision making, yet few providers considered risk factors other than age for average-risk patients. Providers were receptive to the use of a risk assessment tool for ACN when recommending an appropriate screening test for select patients. © 2013 John Wiley & Sons Ltd.

Major bleeding and intracranial hemorrhage risk prediction in patients with atrial fibrillation: Attention to modifiable bleeding risk factors or use of a bleeding risk stratification score? A nationwide cohort study.

Science.gov (United States)

Chao, Tze-Fan; Lip, Gregory Y H; Lin, Yenn-Jiang; Chang, Shih-Lin; Lo, Li-Wei; Hu, Yu-Feng; Tuan, Ta-Chuan; Liao, Jo-Nan; Chung, Fa-Po; Chen, Tzeng-Ji; Chen, Shih-Ann

2018-03-01

While modifiable bleeding risks should be addressed in all patients with atrial fibrillation (AF), use of a bleeding risk score enables clinicians to 'flag up' those at risk of bleeding for more regular patient contact reviews. We compared a risk assessment strategy for major bleeding and intracranial hemorrhage (ICH) based on modifiable bleeding risk factors (referred to as a 'MBR factors' score) against established bleeding risk stratification scores (HEMORR 2 HAGES, HAS-BLED, ATRIA, ORBIT). A nationwide cohort study of 40,450 AF patients who received warfarin for stroke prevention was performed. The clinical endpoints included ICH and major bleeding. Bleeding scores were compared using receiver operating characteristic (ROC) curves (areas under the ROC curves [AUCs], or c-index) and the net reclassification index (NRI). During a follow up of 4.60±3.62years, 1581 (3.91%) patients sustained ICH and 6889 (17.03%) patients sustained major bleeding events. All tested bleeding risk scores at baseline were higher in those sustaining major bleeds. When compared to no ICH, patients sustaining ICH had higher baseline HEMORR 2 HAGES (p=0.003), HAS-BLED (pbleeding scores, c-indexes were significantly higher compared to MBR factors (pbleeding. C-indexes for the MBR factors score was significantly lower compared to all other scores (De long test, all pbleeding risk scores for major bleeding (all pbleeding risk scores had modest predictive value for predicting major bleeding but the best predictive value and NRI was found for the HAS-BLED score. Simply depending on modifiable bleeding risk factors had suboptimal predictive value for the prediction of major bleeding in AF patients, when compared to the HAS-BLED score. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Risk stratification by pre-operative cardiopulmonary exercise testing improves outcomes following elective abdominal aortic aneurysm surgery: a cohort study.

Science.gov (United States)

Goodyear, Stephen J; Yow, Heng; Saedon, Mahmud; Shakespeare, Joanna; Hill, Christopher E; Watson, Duncan; Marshall, Colette; Mahmood, Asif; Higman, Daniel; Imray, Christopher He

2013-05-19

In 2009, the NHS evidence adoption center and National Institute for Health and Care Excellence (NICE) published a review of the use of endovascular aneurysm repair (EVAR) of abdominal aortic aneurysms (AAAs). They recommended the development of a risk-assessment tool to help identify AAA patients with greater or lesser risk of operative mortality and to contribute to mortality prediction.A low anaerobic threshold (AT), which is a reliable, objective measure of pre-operative cardiorespiratory fitness, as determined by pre-operative cardiopulmonary exercise testing (CPET) is associated with poor surgical outcomes for major abdominal surgery. We aimed to assess the impact of a CPET-based risk-stratification strategy upon perioperative mortality, length of stay and non-operative costs for elective (open and endovascular) infra-renal AAA patients. A retrospective cohort study was undertaken. Pre-operative CPET-based selection for elective surgical intervention was introduced in 2007. An anonymized cohort of 230 consecutive infra-renal AAA patients (2007 to 2011) was studied. A historical control group of 128 consecutive infra-renal AAA patients (2003 to 2007) was identified for comparison.Comparative analysis of demographic and outcome data for CPET-pass (AT ≥ 11 ml/kg/min), CPET-fail (AT 11 ml/kg/min was associated with reduced perioperative mortality (open cases only), LOS, survival and inpatient costs (open and endovascular repair) for elective infra-renal AAA surgery.

Application of multivariate probabilistic (Bayesian) networks to substance use disorder risk stratification and cost estimation.

Science.gov (United States)

Weinstein, Lawrence; Radano, Todd A; Jack, Timothy; Kalina, Philip; Eberhardt, John S

2009-09-16

This paper explores the use of machine learning and Bayesian classification models to develop broadly applicable risk stratification models to guide disease management of health plan enrollees with substance use disorder (SUD). While the high costs and morbidities associated with SUD are understood by payers, who manage it through utilization review, acute interventions, coverage and cost limitations, and disease management, the literature shows mixed results for these modalities in improving patient outcomes and controlling cost. Our objective is to evaluate the potential of data mining methods to identify novel risk factors for chronic disease and stratification of enrollee utilization, which can be used to develop new methods for targeting disease management services to maximize benefits to both enrollees and payers. For our evaluation, we used DecisionQ machine learning algorithms to build Bayesian network models of a representative sample of data licensed from Thomson-Reuters' MarketScan consisting of 185,322 enrollees with three full-year claim records. Data sets were prepared, and a stepwise learning process was used to train a series of Bayesian belief networks (BBNs). The BBNs were validated using a 10 percent holdout set. The networks were highly predictive, with the risk-stratification BBNs producing area under the curve (AUC) for SUD positive of 0.948 (95 percent confidence interval [CI], 0.944-0.951) and 0.736 (95 percent CI, 0.721-0.752), respectively, and SUD negative of 0.951 (95 percent CI, 0.947-0.954) and 0.738 (95 percent CI, 0.727-0.750), respectively. The cost estimation models produced area under the curve ranging from 0.72 (95 percent CI, 0.708-0.731) to 0.961 (95 percent CI, 0.95-0.971). We were able to successfully model a large, heterogeneous population of commercial enrollees, applying state-of-the-art machine learning technology to develop complex and accurate multivariate models that support near-real-time scoring of novel payer

N-terminal pro brain natriuretic peptide on admission for early risk stratification of patients with chest pain and no ST-segment elevation.

Science.gov (United States)

Jernberg, Tomas; Stridsberg, Mats; Venge, Per; Lindahl, Bertil

2002-08-07

The study evaluated the prognostic value of single measurement of N-terminal pro brain natriuretic peptide (NT-proBNP) obtained on admission in patients with symptoms suggestive of an acute coronary syndrome and no ST-segment elevation. Patients with symptoms suggestive of an acute coronary syndrome and no ST-segment elevation constitute a large and heterogeneous population. Early risk stratification has been based on clinical background factors, electrocardiography (ECG) and biochemical markers of myocardial damage. The neurohormonal activation has, so far, received less attention. The NT-proBNP was analyzed on admission in 755 patients admitted because of chest pain and no ST-segment elevation. Patients were followed concerning death for 40 months (median). The median NT-proBNP level was 400 (111 to 1646) ng/l. Compared to the lowest quartile, patients in the second, third and fourth quartiles had a relative risk of subsequent death of 4.2 (1.6 to 11.1), 10.7 (4.2 to 26.8) and 26.6 (10.8 to 65.5), respectively. When NT-proBNP was added to a Cox regression model including clinical background factors, ECG and troponin T, the NT-proBNP levels were independently associated with prognosis. A single measurement of NT-proBNP on admission will substantially improve the early risk stratification of patients with symptoms suggestive of an acute coronary syndrome and no ST-segment elevation. A combination of clinical background factors, ECG, troponin T and NT-proBNP obtained on admission will provide a highly discerning tool for risk stratification and further clinical decisions.

Incorporating Stroke and Bleeding Risk Stratification Tools into Atrial Fibrillation Management Making Sense of the Alphabet Soup.

Science.gov (United States)

Deering, Thomas F

2017-01-01

Atrial fibrillation (AF) is a common arrhythmia managed by many physicians in a variety of clinical settings. One of the most important clinical decisions related to effective AF management centers upon the need to perform accurate thromboembolic risk stratification followed by effective management decisions that align with established guidelines. This manuscript will review the present state of the art and provide guidance to physicians to enhance patient outcomes.

Improving risk stratification among veterans diagnosed with prostate cancer: impact of the 17-gene prostate score assay.

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Lynch, Julie A; Rothney, Megan P; Salup, Raoul R; Ercole, Cesar E; Mathur, Sharad C; Duchene, David A; Basler, Joseph W; Hernandez, Javier; Liss, Michael A; Porter, Michael P; Wright, Jonathan L; Risk, Michael C; Garzotto, Mark; Efimova, Olga; Barrett, Laurie; Berse, Brygida; Kemeter, Michael J; Febbo, Phillip G; Dash, Atreya

2018-01-01

Active surveillance (AS) has been widely implemented within Veterans Affairs' medical centers (VAMCs) as a standard of care for low-risk prostate cancer (PCa). Patient characteristics such as age, race, and Agent Orange (AO) exposure may influence advisability of AS in veterans. The 17-gene assay may improve risk stratification and management selection. To compare management strategies for PCa at 6 VAMCs before and after introduction of the Oncotype DX Genomic Prostate Score (GPS) assay. We reviewed records of patients diagnosed with PCa between 2013 and 2014 to identify management patterns in an untested cohort. From 2015 to 2016, these patients received GPS testing in a prospective study. Charts from 6 months post biopsy were reviewed for both cohorts to compare management received in the untested and tested cohorts. Men who just received their diagnosis and have National Comprehensive Cancer Network (NCCN) very low-, low-, and select cases of intermediate-risk PCa. Patient characteristics were generally similar in the untested and tested cohorts. AS utilization was 12% higher in the tested cohort compared with the untested cohort. In men younger than 60 years, utilization of AS in tested men was 33% higher than in untested men. AS in tested men was higher across all NCCN risk groups and races, particular in low-risk men (72% vs 90% for untested vs tested, respectively). Tested veterans exposed to AO received less AS than untested veterans. Tested nonexposed veterans received 19% more AS than untested veterans. Median GPS results did not significantly differ as a factor of race or AO exposure. Men who receive GPS testing are more likely to utilize AS within the year post diagnosis, regardless of age, race, and NCCN risk group. Median GPS was similar across racial groups and AO exposure groups, suggesting similar biology across these groups. The GPS assay may be a useful tool to refine risk assessment of PCa and increase rates of AS among clinically and

Congenital and hereditary causes of sudden cardiac death in young adults: diagnosis, differential diagnosis, and risk stratification.

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Stojanovska, Jadranka; Garg, Anubhav; Patel, Smita; Melville, David M; Kazerooni, Ella A; Mueller, Gisela C

2013-01-01

Sudden cardiac death is defined as death from unexpected circulatory arrest-usually a result of cardiac arrhythmia-that occurs within 1 hour of the onset of symptoms. Proper and timely identification of individuals at risk for sudden cardiac death and the diagnosis of its predisposing conditions are vital. A careful history and physical examination, in addition to electrocardiography and cardiac imaging, are essential to identify conditions associated with sudden cardiac death. Among young adults (18-35 years), sudden cardiac death most commonly results from a previously undiagnosed congenital or hereditary condition, such as coronary artery anomalies and inherited cardiomyopathies (eg, hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy [ARVC], dilated cardiomyopathy, and noncompaction cardiomyopathy). Overall, the most common causes of sudden cardiac death in young adults are, in descending order of frequency, hypertrophic cardiomyopathy, coronary artery anomalies with an interarterial or intramural course, and ARVC. Often, sudden cardiac death is precipitated by ventricular tachycardia or fibrillation and may be prevented with an implantable cardioverter defibrillator (ICD). Risk stratification to determine the need for an ICD is challenging and involves imaging, particularly echocardiography and cardiac magnetic resonance (MR) imaging. Coronary artery anomalies, a diverse group of congenital disorders with a variable manifestation, may be depicted at coronary computed tomographic angiography or MR angiography. A thorough understanding of clinical risk stratification, imaging features, and complementary diagnostic tools for the evaluation of cardiac disorders that may lead to sudden cardiac death is essential to effectively use imaging to guide diagnosis and therapy.

Microalbuminuria could improve risk stratification in patients with TIA and minor stroke.

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Elyas, Salim; Shore, Angela C; Kingwell, Hayley; Keenan, Samantha; Boxall, Leigh; Stewart, Jane; James, Martin A; Strain, William David

2016-09-01

Transient ischemic attacks (TIA) and minor strokes are important risk factors for recurrent strokes. Current stroke risk prediction scores such as ABCD2, although widely used, lack optimal sensitivity and specificity. Elevated urinary albumin excretion predicts cardiovascular disease, stroke, and mortality. We explored the role of microalbuminuria (using albumin creatinine ratio (ACR)) in predicting recurrence risk in patients with TIA and minor stroke. Urinary ACR was measured on a spot sample in 150 patients attending a daily stroke clinic with TIA or minor stroke. Patients were followed up at day 7, 30, and 90 to determine recurrent stroke, cardiovascular events, or death. Eligible patients had a carotid ultrasound Doppler investigation. High-risk patients were defined as those who had an event within 90 days or had >50% internal carotid artery (ICA) stenosis. Fourteen (9.8%) recurrent events were reported by day 90 including two deaths. Fifteen patients had severe ICA stenosis. In total, 26 patients were identified as high risk. These patients had a higher frequency of previous stroke or hypercholesterolemia compared to low-risk patients (P = 0.04). ACR was higher in high-risk patients (3.4 [95% CI 2.2-5.2] vs. 1.7 [1.5-2.1] mg/mmol, P = 0.004), independent of age, sex, blood pressure, diabetes, and previous stroke. An ACR greater than 1.5 mg/mmol predicted high-risk patients (Cox proportional hazard ratio 3.5 (95% CI 1.3-9.5, P = 0.01). After TIA or minor stroke, a higher ACR predicted recurrent events and significant ICA stenosis. Incorporation of urinary ACR from a spot sample in the acute setting could improve risk stratification in patients with TIA and minor stroke.

Risk stratification for venous thromboembolism in patients with testicular germ cell tumors.

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Angelika Bezan

Full Text Available Patients with testicular germ cell tumors (TGCT have an increased risk for venous thromboembolism (VTE. We identified risk factors for VTE in this patient cohort and developed a clinical risk model.In this retrospective cohort study at the Medical University of Graz we included 657 consecutive TGCT patients across all clinical stages. A predictive model for VTE was developed and externally validated in 349 TGCT patients treated at the University Hospital Zurich.Venous thromboembolic events occurred in 34 (5.2% patients in the Graz cohort. In univariable competing risk analysis, higher clinical stage (cS and a retroperitoneal lymphadenopathy (RPLN were the strongest predictors of VTE (p<0.0001. As the presence of a RPLN with more than 5cm in greatest dimension without coexisting visceral metastases is classified as cS IIC, we constructed an empirical VTE risk model with the following four categories (12-month-cumulative incidence: cS IA-B 8/463 patients (1.7%, cS IS-IIB 5/86 patients (5.9%, cS IIC 3/21 patients (14.3% and cS IIIA-C 15/70 patients (21.4%. This risk model was externally validated in the Zurich cohort (12-month-cumulative incidence: cS IA-B (0.5%, cS IS-IIB (6.0%, cS IIC (11.1% and cS IIIA-C (19.1%. Our model had a significantly higher discriminatory performance than a previously published classifier (RPLN-VTE-risk-classifier which is based on the size of RPLN alone (AUC-ROC: 0.75 vs. 0.63, p = 0.007.According to our risk stratification, TGCT patients with cS IIC and cS III disease have a very high risk of VTE and may benefit from primary thromboprophylaxis for the duration of chemotherapy.

Pharmacogenetic Risk Stratification in Angiotensin-Converting Enzyme Inhibitor-Treated Patients with Congestive Heart Failure

DEFF Research Database (Denmark)

Nelveg-Kristensen, Karl Emil; Busk Madsen, Majbritt; Torp-Pedersen, Christian

2015-01-01

BACKGROUND: Evidence for pharmacogenetic risk stratification of angiotensin-converting enzyme inhibitor (ACEI) treatment is limited. Therefore, in a cohort of ACEI-treated patients with congestive heart failure (CHF), we investigated the predictive value of two pharmacogenetic scores...... SNPs of the angiotensin-converting enzyme gene (rs4343) and ABO blood group genes (rs495828 and rs8176746). METHODS: Danish patients with CHF enrolled in the previously reported Echocardiography and Heart Outcome Study were included. Subjects were genotyped and categorized according to pharmacogenetic.......05 [95% CI 0.79-1.40]), respectively. CONCLUSIONS: We found no association between either of the analyzed pharmacogenetic scores and fatal outcomes in ACEI-treated patients with CHF....

The value of exercise radionuclide ventriculography in risk stratification in patients with known or suspected coronary artery disease

International Nuclear Information System (INIS)

Iskandrian, A.S.; Hakki, A.H.; Kane, S.; Schenk, C.

1985-01-01

This study examined the value of rest and exercise (EX) radionuclide ventriculography (RNV) in risk stratification in 392 pts with suspected or known coronary artery disease who were being evaluated for anginal symptoms. There were 289 men and 203 women, aged 55 +- 12 years (mean +- SD). There were 20 cardiac events in the followup period of up to 4 years (19 +- 10 months): 14 pts died of cardiac causes and 6 had non-fatal acute myocardial infarctions. The pts with and without events did not differ in age, clinical presentation, risk factors, and rest and EX ECGs. However, pts with events had lower EX systolic blood pressure (p < 0.02); lower EX duration; (5.5 +- 2.5 vs 7.6 +- 3.7 minutes, p < 0.0l), lower resting left ventricular (LV) ejection fraction (EF) (p = 0.001), and lower EX EF (35 +- 17% vs 56 +- 15%, p = 0.0001). The change in EF from rest to EX was not significantly different (-0.1 +- 6.1 vs 3 +- 9.9). Univariate survival analysis (Cox model) showed several descriptors related to prognosis: EX EF, rest EF, wall motion and EX duration. Multivariate analysis, however, identified the EX EF as the only significant predictor (X/sup 2/ = 19.9). None of the other variables added independent information to that provided by the EX EF. Actuarial lie table analysis showed that the risk increased as the EX EF decreased, when pts were grouped into those with EXEF ≥ 50%, 30-49%, and <30%., (p = 0.001, Mantel-Cox). Thus, the EX RNV is useful in risk stratification; the EX EF is the best descriptor that categorizes pts into different risk groups

PCA-based polling strategy in machine learning framework for coronary artery disease risk assessment in intravascular ultrasound: A link between carotid and coronary grayscale plaque morphology.

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Araki, Tadashi; Ikeda, Nobutaka; Shukla, Devarshi; Jain, Pankaj K; Londhe, Narendra D; Shrivastava, Vimal K; Banchhor, Sumit K; Saba, Luca; Nicolaides, Andrew; Shafique, Shoaib; Laird, John R; Suri, Jasjit S

2016-05-01

Percutaneous coronary interventional procedures need advance planning prior to stenting or an endarterectomy. Cardiologists use intravascular ultrasound (IVUS) for screening, risk assessment and stratification of coronary artery disease (CAD). We hypothesize that plaque components are vulnerable to rupture due to plaque progression. Currently, there are no standard grayscale IVUS tools for risk assessment of plaque rupture. This paper presents a novel strategy for risk stratification based on plaque morphology embedded with principal component analysis (PCA) for plaque feature dimensionality reduction and dominant feature selection technique. The risk assessment utilizes 56 grayscale coronary features in a machine learning framework while linking information from carotid and coronary plaque burdens due to their common genetic makeup. This system consists of a machine learning paradigm which uses a support vector machine (SVM) combined with PCA for optimal and dominant coronary artery morphological feature extraction. Carotid artery proven intima-media thickness (cIMT) biomarker is adapted as a gold standard during the training phase of the machine learning system. For the performance evaluation, K-fold cross validation protocol is adapted with 20 trials per fold. For choosing the dominant features out of the 56 grayscale features, a polling strategy of PCA is adapted where the original value of the features is unaltered. Different protocols are designed for establishing the stability and reliability criteria of the coronary risk assessment system (cRAS). Using the PCA-based machine learning paradigm and cross-validation protocol, a classification accuracy of 98.43% (AUC 0.98) with K=10 folds using an SVM radial basis function (RBF) kernel was achieved. A reliability index of 97.32% and machine learning stability criteria of 5% were met for the cRAS. This is the first Computer aided design (CADx) system of its kind that is able to demonstrate the ability of coronary

Preoperative risk stratification using metabolic parameters of {sup 18}F-FDG PET/CT in patients with endometrial cancer

Energy Technology Data Exchange (ETDEWEB)

Kitajima, Kazuhiro [Kobe University School of Medicine, Department of Radiology, Kobe (Japan); Kobe University Graduate School of Medicine, Department of Radiology, Kobe (Japan); Suenaga, Yuko; Ueno, Yoshiko; Maeda, Tetsuo; Sofue, Keitarou; Sugimura, Kazuro [Kobe University School of Medicine, Department of Radiology, Kobe (Japan); Ebina, Yasuhiko; Yamada, Hideto [Kobe University School of Medicine, Department of Obstetrics and Gynecology, Kobe (Japan); Okunaga, Takashi; Kubo, Kazuhiro [Kobe University Hospital, Department of Radiology Division, Kobe (Japan); Kanda, Tomonori [Teikyo University School of Medicine, Department of Radiology, Tokyo (Japan); Tamaki, Yukihisa [Shimane University School of Medicine, Department of Radiation Oncology, Shimane (Japan)

2015-07-15

To evaluate the usefulness of metabolic parameters obtained by {sup 18}F-FDG PET/CT for preoperative stratification of high-risk and low-risk endometrial carcinomas. Preoperative {sup 18}F-FDG PET/CT was performed in 56 women with endometrial cancer. Maximum standardized uptake values (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG) of primary tumours were compared with clinicopathological features of surgical specimens. Diagnostic performance in terms of differentiation of low-risk disease (endometrioid histology, histological grade 1 or 2, invasion of less than half of the myometrium, and FIGO stage I) from high-risk disease was assessed. MTV and TLG were significantly higher in patients with higher histological grade (p = 0.0026 and p = 0.034), larger tumour size (p = 0.002 and p = 0.0017), lymphovascular space involvement (LVSI; p = 0.012 and p = 0.0051), myometrial invasion (p = 0.027 and p = 0.031), cervical stromal invasion (p = 0.023 and p = 0.014), ovarian metastasis (p = 0.00022 and p = 0.00034), lymph node metastasis (p < 0.0001 and p < 0.0001), and higher FIGO stage (p = 0.0011 and p = 0.00048). SUVmax was significantly higher in patients with larger tumour size (p = 0.0025), LVSI (p = 0.00023) and myometrial invasion (p < 0.0001). The areas under the ROC curves (AUCs) for distinguishing high-risk from low-risk carcinoma were 0.625, 0.829 and 0.797 for SUVmax, MTV and TLG, respectively. AUCs for both MTV and TLG were significantly larger than that for SUVmax (p = 0.0049 and p = 0.021). The optimal TLG cut-off value of 70.2, determined by ROC analysis, was found to have 72.0 % sensitivity and 74.2 % specificity for risk stratification. MTV and TLG of primary endometrial cancer show better correlations with clinicopathological features and are more useful for differentiating high-risk from low-risk carcinoma than SUVmax. (orig.)

Risk Stratification of Acute Kidney Injury Using the Blood Urea Nitrogen/Creatinine Ratio in Patients With Acute Decompensated Heart Failure.

Science.gov (United States)

Takaya, Yoichi; Yoshihara, Fumiki; Yokoyama, Hiroyuki; Kanzaki, Hideaki; Kitakaze, Masafumi; Goto, Yoichi; Anzai, Toshihisa; Yasuda, Satoshi; Ogawa, Hisao; Kawano, Yuhei

2015-01-01

Risk stratification of acute kidney injury (AKI) is important for acute decompensated heart failure (ADHF). The aim of this study was to determine whether clinical markers, such as the blood urea nitrogen/creatinine ratio (BUN/Cr) or BUN or creatinine values alone, stratify the risk of AKI for mortality. In all, 371 consecutive ADHF patients were enrolled in the study. AKI was defined as serum creatinine ≥0.3 mg/dl or a 1.5-fold increase in serum creatinine levels within 48 h. During ADHF therapy, AKI occurred in 99 patients; 55 patients died during the 12-month follow-up period. Grouping patients according to AKI and a median BUN/Cr at admission of 22.1 (non-AKI+low BUN/Cr, non-AKI+high BUN/Cr, AKI+low BUN/Cr, and AKI+high BUN/Cr groups) revealed higher mortality in the AKI+high BUN/Cr group (log-rank test, Phigh BUN/Cr and mortality, whereas the association with AKI+low BUN/Cr did not reach statistical significance. When patients were grouped according to AKI and median BUN or creatinine values at admission, AKI was associated with mortality, regardless of BUN or creatinine. The combination of AKI and elevated BUN/Cr, but not BUN or creatinine individually, is linked with an increased risk of mortality in ADHF patients, suggesting that the BUN/Cr is useful for risk stratification of AKI.

Management of acute paracetamol (acetaminophen) toxicity: a standardised proforma improves risk assessment and overall risk stratification by emergency medicine doctors.

Science.gov (United States)

McQuade, David J; Aknuri, Srikanth; Dargan, Paul I; Wood, David M

2012-12-01

Paracetamol (acetaminophen) poisoning is the most common toxicological presentation in the UK. Doctors managing patients with paracetamol poisoning need to assess the risk of their patient developing hepatotoxicity before determining appropriate treatment. Patients deemed to be at 'high risk' of hepatotoxicity have lower treatment thresholds than those deemed to be at 'normal risk'. Errors in this process can lead to harmful or potentially fatal under or over treatment. To determine how well treating doctors assess risk factor status and whether a standardised proforma is useful in the risk stratification process. Retrospective 12-month case note review of all patients presenting with paracetamol poisoning to our large inner-city emergency department. Data were collected on the documentation of risk factors, the presence of a local hospital proforma and treatment outcomes. 249 presentations were analysed and only 59 (23.7%) had full documentation of all the risk factors required to make a complete risk assessment. 56 of the 59 (94.9%) had the local hospital proforma included in the notes; the remaining 3 (5.1%) had full documentation of risk factors despite the absence of a proforma. A local hospital proforma was more likely to be included in the emergency department notes in those with 'adequate documentation' (78 out of 120 (65%)) than for those with 'inadequate documentation' (16 out of 129 (12.4%)); X(2), pparacetamol poisoning.

Risk stratification of patients with hypertension using exercise thallium-201 scintigraphy

International Nuclear Information System (INIS)

Iskandrian, A.S.; Hakki, A.H.; Kane, S.

1985-01-01

Hypertension (HT) is an important risk factor in coronary heart disease (CHD) and cardiac morbidity and mortality. This study examined the value of clinical, ECG, exercise (EX) and thallium-201 imaging descriptors that identify patients (pts) with HT at high risk. The 337 pts in the study underwent EX thallium-201 testing for evaluation of chest pain due to suspected or proven CHD. The mean age was 55 years, of whom 79% were still on active anti-HT therapy at the time of the study. The EX thallium scintigrams were evaluated qualitatively and quantitively using circumferential profile analysis. The scans were abnormal in 162 pts (48%) and reversible perfusion defects were present in 106 of the 162 pts (65%). At a folllowup fo up to 74 months, (15 +- 9 mean +- SD), 11 pts had hard cardiac events: 2 died of cardiac causes and 9 had non-fatal acute myocardial infractions. There were no significant differences between those with and without events in age, EX heart rate and double product, EX duration, blood pressure and EX ECG changes. Univariate and multivariate survival analysis (Cox regression model) of important clinical, ECG, EX and thallium variables, identified the presence of abnormal EX images as the only predictor of outcome. (X/sup 2/ = 5.4, p< 0.02). No other variable provided additional prognostic information. Actuarial life table analysis showed that pts with abnormal images had significantly more events than those with normal images (p = 0.008, Mantel-Cox). Thus, EX thallium imaging is useful in risk stratification in pts with HT. The presence of abnormal images identify a subgroup at high risk for future events

Combination of Bcl-2 and MYC protein expression improves high-risk stratification in diffuse large B-cell lymphoma

Directory of Open Access Journals (Sweden)

Wang J

2015-09-01

Full Text Available Jing Wang,* Min Zhou,* Jing-Yan Xu,* Bing Chen, Jian OuyangDepartment of Hematology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, People’s Republic of China*These authors contributed equally to this work and should be considered as cofirst authorsPurpose: To evaluate whether the addition of two biological markers (MYC and BCL-2 protein overexpression improves the stratification of high-risk patients with diffuse large B-cell lymphoma (DLBCL.Method: Seven risk factors were identified at diagnosis, and a maximum of 7 points were assigned to each patient. The patients were classified according to four risk groups: low (0–1, low-intermediate (2–3, high-intermediate (4, and high (5–7. Only high-risk patients with DLBCL were included in this analysis. We retrospectively examined 20 cases from 2008 to 2013 at the Nanjing Drum Tower Hospital.Results: The median expression of MYC protein was 60%, and 17 of 20 (65% evaluable cases overexpressed MYC. The median expression of BCL-2 protein was also 60%. Eighteen of 20 (90% evaluable cases showed BCL-2 overexpression. Additionally, 12 out of 20 cases (60% demonstrated coexpression of MYC and BCL-2 proteins. The percentages of overall survival and progression-free survival at the median follow-up time (36 months were 33.3%±16.1% and 16.9%±13.5%, respectively. By comparison, nine, four, and 20 patients were classified as high risk based on the International Prognostic Index (IPI, National Comprehensive Cancer Network(NCCN-IPI, and revised IPI criteria, respectively. According to the IPI and NCCN-IPI stratification, the risk groups demonstrated closely overlapping survival curves. In addition, four out of 20 cases were identified as low-intermediate risk according to the NCCN-IPI criteria.Conclusion: The addition of MYC and BCL-2 protein expression to the IPI could identify a subset of DLBCL patients with high-risk clinicopathological characteristics and

Global cardiovascular risk stratification among hypertensive patients treated in a Family Health Unit of Parnaíba, Piauí - doi: 10.5020/18061230.2012.p287

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Elce de Seixas Nascimento

2012-11-01

Full Text Available Objective: To stratify the global cardiovascular risk among hypertensive patients attended in a Family Health Unit (FHU. Methods: A quantitative, cross-sectional and descriptive study with population of hypertensive patients undergoing treatment in a FHU, module 34, in Parnaíba, Piauí, Brazil, in the period from July to August 2011. The sample consisted of 45 volunteers, selected by free demand conglomerate, who filled a form with questions that support the analysis and Global Cardiovascular Risk stratification (GCR, according to the VI Brazilian Guidelines on Hypertension (VI BGH - 2010, The European Society of Cardiology (ESC and European Society of Hypertension (ESH - 2007. The subjects were then submitted to measurement of blood pressure (BP, waist circumference (WC and body mass index (BMI. Results: The most evident risk factor in the sample was overweight/obesity in 75.5% (n=34, followed by sedentary lifestyle in 73.3% (n=33 and hypercholesterolemia in 55.5% (n=25. The data collected resulted in a stratification in which 84.4% (n=38 presented high added risk and 15.5% (n=7 a very high added risk of presenting cardiovascular events in the next 10 years. Conclusion: The stratification in the population studied indicated high incidence of such factors, pointing to the need of interfering in this population segment, in order to promote changes in lifestyle that generate prevention and control of cardiovascular diseases.

Usefulness of ST elevation score by using vector-projected virtual 187-channel ECG for risk stratification in patients with Brugada-type ECG pattern

Directory of Open Access Journals (Sweden)

Shoko Ishikawa

2012-08-01

Conclusion: The ST elevation score in VP-ECG objectively documented the degree of ST elevation in surface ECG in Brugada-type ECG patterns. The ST-elevation score might be useful for risk stratification in patients with asymptomatic Brugada syndrome.

Self-Reported Stroke Risk Stratification: Reasons for Geographic and Racial Differences in Stroke Study.

Science.gov (United States)

Howard, George; McClure, Leslie A; Moy, Claudia S; Howard, Virginia J; Judd, Suzanne E; Yuan, Ya; Long, D Leann; Muntner, Paul; Safford, Monika M; Kleindorfer, Dawn O

2017-07-01

The standard for stroke risk stratification is the Framingham Stroke Risk Function (FSRF), an equation requiring an examination for blood pressure assessment, venipuncture for glucose assessment, and ECG to determine atrial fibrillation and heart disease. We assess a self-reported stroke risk function (SRSRF) to stratify stroke risk in comparison to the FSRF. Participants from the REGARDS study (Reasons for Geographic and Racial Differences in Stroke) were evaluated at baseline and followed for incident stroke. The FSRF was calculated using directly assessed stroke risk factors. The SRSRF was calculated from 13 self-reported questions to exclude those with prevalent stroke and assess stroke risk. Proportional hazards analysis was used to assess incident stroke risk using the FSRF and SRSRF. Over an average 8.2-year follow-up, 939 of 23 983 participants had a stroke. The FSRF and SRSRF produced highly correlated risk scores ( r Spearman =0.852; 95% confidence interval, 0.849-0.856); however, the SRSRF had higher discrimination of stroke risk than the FSRF (c SRSRF =0.7266; 95% confidence interval, 0.7076-0.7457; c FSRF =0.7075; 95% confidence interval, 0.6877-0.7273; P =0.0038). The 10-year stroke risk in the highest decile of predicted risk was 11.1% for the FSRF and 13.4% for the SRSRF. A simple self-reported questionnaire can be used to identify those at high risk for stroke better than the gold standard FSRF. This instrument can be used clinically to easily identify individuals at high risk for stroke and also scientifically to identify a subpopulation enriched for stroke risk. © 2017 American Heart Association, Inc.

Value of cyclin A immunohistochemistry for cancer risk stratification in Barrett esophagus surveillance: A multicenter case-control study.

Science.gov (United States)

van Olphen, Sophie H; Ten Kate, Fiebo J C; Doukas, Michail; Kastelein, Florine; Steyerberg, Ewout W; Stoop, Hans A; Spaander, Manon C; Looijenga, Leendert H J; Bruno, Marco J; Biermann, Katharina

2016-11-01

The value of endoscopic Barrett esophagus (BE) surveillance based on histological diagnosis of low-grade dysplasia (LGD) remains debated given the lack of adequate risk stratification. The aim of this study was to evaluate the predictive value of cyclin A expression and to combine these results with our previously reported immunohistochemical p53, AMACR, and SOX2 data, to identify a panel of biomarkers predicting neoplastic progression in BE.We conducted a case-control study within a prospective cohort of 720 BE patients. BE patients who progressed to high-grade dysplasia (HGD, n = 37) or esophageal adenocarcinoma (EAC, n = 13), defined as neoplastic progression, were classified as cases and patients without neoplastic progression were classified as controls (n = 575). Cyclin A expression was determined by immunohistochemistry in all 625 patients; these results were combined with the histological diagnosis and our previous p53, AMACR, and SOX2 data in loglinear regression models. Differences in discriminatory ability were quantified as changes in area under the ROC curve (AUC) for predicting neoplastic progression.Cyclin A surface positivity significantly increased throughout the metaplasia-dysplasia-carcinoma sequences and was seen in 10% (107/1050) of biopsy series without dysplasia, 33% (109/335) in LGD, and 69% (34/50) in HGD/EAC. Positive cyclin A expression was associated with an increased risk of neoplastic progression (adjusted relative risk (RR) 2.4; 95% CI: 1.7-3.4). Increases in AUC were substantial for P53 (+0.05), smaller for SOX2 (+0.014), minor for cyclin A (+0.003), and none for AMARC (0.00).Cyclin A immunopositivity was associated with an increased progression risk in BE patients. However, compared to p53 and SOX2, the incremental value of cyclin A was limited. The use of biomarkers has the potential to significantly improve risk stratification in BE.

Risk stratification in cardiovascular disease primary prevention - scoring systems, novel markers, and imaging techniques.

LENUS (Irish Health Repository)

Zannad, Faiez

2012-04-01

The aim of this paper is to review and discuss current methods of risk stratification for cardiovascular disease (CVD) prevention, emerging biomarkers, and imaging techniques, and their relative merits and limitations. This report is based on discussions that took place among experts in the area during a special CardioVascular Clinical Trialists workshop organized by the European Society of Cardiology Working Group on Cardiovascular Pharmacology and Drug Therapy in September 2009. Classical risk factors such as blood pressure and low-density lipoprotein cholesterol levels remain the cornerstone of risk estimation in primary prevention but their use as a guide to management is limited by several factors: (i) thresholds for drug treatment vary with the available evidence for cost-effectiveness and benefit-to-risk ratios; (ii) assessment may be imprecise; (iii) residual risk may remain, even with effective control of dyslipidemia and hypertension. Novel measures include C-reactive protein, lipoprotein-associated phospholipase A(2) , genetic markers, and markers of subclinical organ damage, for which there are varying levels of evidence. High-resolution ultrasound and magnetic resonance imaging to assess carotid atherosclerotic lesions have potential but require further validation, standardization, and proof of clinical usefulness in the general population. In conclusion, classical risk scoring systems are available and inexpensive but have a number of limitations. Novel risk markers and imaging techniques may have a place in drug development and clinical trial design. However, their additional value above and beyond classical risk factors has yet to be determined for risk-guided therapy in CVD prevention.

Adenosine stress and exercise 99Tcm-MIBI myocardial perfusion imaging in the diagnosis and risk stratification of patients with unstable angina

International Nuclear Information System (INIS)

Jia Peng; Guo Wanhua; Xu Shoulin; Feng Xuefeng

2008-01-01

Objective: The aim of this study was to evaluate the clinical value of adenosine stress or exercise 99 Tc m -methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging in the diagnosis and risk stratification of patients with unstable angina. Methods: Eighty-seven hospitalized patients with unstable angina [54 men and 33 women, aged of (56.5±12.5) years] underwent adenosine stress or exercise myocardial perfusion imaging and coronary angiography. Patients were followed up. Results: Fifty-seven patients had abnormal myocardial perfusion imaging and significant coronary artery stenosis. Ten patients had abnormal myocardial perfusion imaging but normal coronary angiography. Eight patients had normal myocardial perfusion imaging but significant coronary artery stenosis. Twelve patients had normal myocardial perfusion imaging and normal coronary angiography. Patients with abnormal myocardial perfusion imaging had worse prognosis. There was relationship between cardiac events and the extent and severity of myocardial ischemia. Conclusion: Adenosine stress and exercise myocardial perfusion imaging is of important clinical value in the diagnosis and risk stratification of patients with unstable angina. (authors)

Numerical Investigation on Effects of Assigned EGR Stratification on a Heavy Duty Diesel Engine with Two-Stage Fuel Injection

Directory of Open Access Journals (Sweden)

Zhaojie Shen

2018-02-01

Full Text Available External exhaust gas recirculation (EGR stratification in diesel engines contributes to reduction of toxic emissions. Weak EGR stratification lies in that strong turbulence and mixing between EGR and intake air by current introduction strategies of EGR. For understanding of ideal EGR stratification combustion, EGR was assigned radically at −30 °CA after top dead center (ATDC to organize strong EGR stratification using computational fluid dynamics (CFD. The effects of assigned EGR stratification on diesel performance and emissions are discussed in this paper. Although nitric oxides (NOx and soot emissions are both reduced by means of EGR stratification compared to uniform EGR, the trade-off between NOx and soot still exists under the condition of arranged EGR stratification with different fuel injection strategies. A deterioration of soot emissions was observed when the interval between main and post fuel injection increased, while NO emissions increased first then reduced. The case with a 4 °CA interval between main and post fuel injection is suitable for acceptable NO and soot emissions. Starting the main fuel injection too early and too late is not acceptable, which results in high NO emissions and high soot emissions respectively. The start of the main fuel injection −10 °CA ATDC is suitable.

[Integrated prevention and control strategy for dengue in Mesoamerica].

Science.gov (United States)

Gómez-Dantés, Héctor; San Martín, José Luis; Danis-Lozano, Rogelio; Manrique-Saide, Pablo

2011-01-01

Dengue in the Americas is a public health problem in ascent. The control strategies have not been effective when sustained in the intensive use of insecticides and poor community participation. The Mesoamerican Initiative for the Prevention and the Integrated Control of Dengue synthesizes the works generated by the Integrated Strategy of the Pan-American Health Organization (PAHO) and the risks stratification strategy designed by the countries of the Mesoamerican region. The objective is to progressively reduce the incidence of dengue cases until a 50% reduction is reached over a five years period. This document describes the elements for the risk stratification, the activities for prevention and control organized by levels of intensity and frequency and the indicators used to pursuit the objectives. To face the dispersion of the problem a concentration of efforts for control in the areas of greater risk is presented; the opportunity in the detection of cases is highlighted to tackle the fast dissemination of the infection; focus on the most productive breeding sites is proposed to battle against the vast dissemination of the breeding sites; and the severity of the infection must be addressed by capable clinical human resources. This strategy was designed along with the national representatives of the control programs to create master plans that provided the basis for the integrated prevention and control of dengue in the Mesoamerican region.

Value of planar 201Tl imaging in risk stratification of patients recovering from acute myocardial infarction

International Nuclear Information System (INIS)

Gibson, R.S.; Watson, D.D.

1991-01-01

Although exercise ECG testing has been shown to have important prognostic value after acute myocardial infarction, exercise 201Tl scintigraphy offers several potential advantages, including: (1) increased sensitivity for detecting residual myocardial ischemia; (2) the ability to localize ischemia to a specific area or areas subtended by a specific coronary artery; (3) the ability to identify exercise-induced left ventricular dysfunction, which is manifested by increased lung uptake or transient left ventricular dilation; and (4) more reliable risk stratification of individual patients. The more optimal prognostic efficiency of 201Tl scintigraphy partially results from the fact that the error rate in falsely classifying patients as low risk is significantly smaller with 201Tl scintigraphy than with stress ECG. Because of these substantial advantages, there seems to be adequate rationale for recommending exercise perfusion imaging rather than exercise ECG alone as the preferred method for evaluating mortality and morbidity risks after acute myocardial infarction

Cardiac stress test as a risk-stratification tool for posttransplant cardiac outcomes in diabetic kidney transplant recipients.

Science.gov (United States)

Singh, Neeraj; Parikh, Samir; Bhatt, Udayan; Vonvisger, Jon; Nori, Uday; Hasan, Ayesha; Samavedi, Srinivas; Andreoni, Kenneth; Henry, Mitchell; Pelletier, Ronald; Rajab, Amer; Elkhammas, Elmahdi; Pesavento, Todd

2012-12-27

The utility of cardiac stress testing as a risk-stratification tool before kidney transplantation remains debatable owing to discordance with coronary angiography and outcome yields at different centers. We conducted a retrospective study of 273 diabetic kidney transplant recipients from 2006 to 2010. By protocol, all diabetic patients underwent pharmacological radionucleotide stress test or dobutamine stress echocardiography before transplant. We compared the 1-year cardiac outcomes between those with negative stress test results and those with positive stress test results. Patients with a positive stress test result (n=67) underwent coronary angiogram, and significant coronary artery disease (≥70% coronary stenosis) was found in 35 (52.2%) patients. Of the latter, 32 (91.4%) underwent cardiac revascularization (24 underwent cardiac stenting and 8 underwent coronary artery bypass grafting). The rest (n=35) were treated medically. Within 1 year after transplant, the group with positive stress test results experienced more cardiac events (34.3% vs. 3.9%, P<0.001) including acute myocardial infarction (22.4% vs. 3.4%, P<0.001) and ventricular arrhythmias (8.9% vs. 0.05%, P=0.001), higher all-cause mortality (19.4% vs. 4.8%, P<0.001), and cardiac mortality (17.9% vs. 0.9%, P<0.001) compared with the group with negative stress test results. In this diabetic population, stress testing showed positive and negative predictive values of 34.3% and 96.1%, respectively. Pharmacological cardiac stress testing provided excellent risk stratification in diabetic kidney transplant recipients.

Cattle farmers’ perceptions of risk and risk management strategies

DEFF Research Database (Denmark)

Bishu, Kinfe G.; O'Reilly, Seamus; Lahiff, Edward

2018-01-01

This study analyzes cattle farmers’ perceptions of risk and risk management strategies in Tigray, Northern Ethiopia. We use survey data from a sample of 356 farmers based on multistage random sampling. Factor analysis is employed to classify scores of risk and management strategies, and multiple...... utilization were perceived as the most important strategies for managing risks. Livestock disease and labor shortage were perceived as less of a risk by farmers who adopted the practice of zero grazing compared to other farmers, pointing to the potential of this practice for risk reduction. We find strong...... evidence that farmers engage in multiple risk management practices in order to reduce losses from cattle morbidity and mortality. The results suggest that government strategies that aim at reducing farmers’ risk need to be tailored to specific farm and farmer characteristics. Findings from this study have...

D-dimer testing for safe exclusion and risk stratification in patients with acute pulmonary embolism in primary care

Directory of Open Access Journals (Sweden)

Zhou Yin

2015-01-01

Full Text Available Background: Safe exclusion and risk stratification are currently recommended for the initial management of patients with acute pulmonary embolism (APE. The aim of this study was to assess the safe exclusion and risk stratification value of D-dimer (DD for APE when tested at the beginning of admission. Materials and Methods: All consecutive Chinese APE patients and controls were recruited from January 2010 to December 2012. All measurements of serum indexes were made in duplicate and blinded to the patients′ status. All the 40 patients with the first episode of APE were confirmed by multi-detector computed tomographic pulmonary angiography. The plasma prothrombin time (PT, activated partial thromboplastin time, thrombin time, fibrinogen, and DD levels were measured within 24 h of admission. We used the Mann-Whitney U-test to determine the differences between groups and drew receiver operator characteristic curve to evaluate the indexes′ value in the APE screening. Results: The PT and DD in the APE group were significantly higher than those in the disease control group (P 1820 μg/L as cut-off value, the sensitivity, specificity, positive and negative predictive value was 82.5%, 75.2%, 56.9%, and 91.6%, respectively. Conclusion: The patients with APE showed significant higher DD levels compared with disease controls, suggesting a negative qualitative DD test result can safely and efficiently exclude APE in primary care.

BRAF mutation in papillary thyroid microcarcinoma – additional marker of risk stratification

Directory of Open Access Journals (Sweden)

Dmitriy Yuriyevich Semyonov

2014-11-01

Full Text Available BackgroundPapillary thyroid microcarcinoma (PTMC is heterogeneous group of tumor less than 1 cm in the diameter. The volume of surgical treatment stay unstable because unclear biological potential of PTMC.AimThe aim of our study was to assess the utility of BRAF gene mutation as preoperative additional marker of risk stratification.Materials and methodsWe include 44 patient who were operated in general surgery department Pavlov State Medical University from 2001 to 2013. In all 44 cases BRAF gene mutation was detected and compared with clinic-morphological features (multifocality, invasive growth, lymph node metastasis, recurrence retrospectivelyResultsIn our study the frequency of BRAF gene mutation was 68.2%. On multivariate regression analysis the presence of bilateral tumoural foci, lymph node metastasis and the presence of capsular invasion were significantly related to BRAF positive gene status.ConclusionsThus, appropriate volume for the BRAF positive PTMC is thyroidectomy with central compartment lymph node dissection.

Diagnostic test strategies in children at increased risk of inflammatory bowel disease in primary care.

Directory of Open Access Journals (Sweden)

Gea A Holtman

Full Text Available In children with symptoms suggestive of inflammatory bowel disease (IBD who present in primary care, the optimal test strategy for identifying those who require specialist care is unclear. We evaluated the following three test strategies to determine which was optimal for referring children with suspected IBD to specialist care: 1 alarm symptoms alone, 2 alarm symptoms plus c-reactive protein, and 3 alarm symptoms plus fecal calprotectin.A prospective cohort study was conducted, including children with chronic gastrointestinal symptoms referred to pediatric gastroenterology. Outcome was defined as IBD confirmed by endoscopy, or IBD ruled out by either endoscopy or unremarkable clinical 12 month follow-up with no indication for endoscopy. Test strategy probabilities were generated by logistic regression analyses and compared by area under the receiver operating characteristic curves (AUC and decision curves.We included 90 children, of whom 17 (19% had IBD (n = 65 from primary care physicians, n = 25 from general pediatricians. Adding fecal calprotectin to alarm symptoms increased the AUC significantly from 0.80 (0.67-0.92 to 0.97 (0.93-1.00, but adding c-reactive protein to alarm symptoms did not increase the AUC significantly (p > 0.05. Decision curves confirmed these patterns, showing that alarm symptoms combined with fecal calprotectin produced the diagnostic test strategy with the highest net benefit at reasonable threshold probabilities.In primary care, when children are identified as being at high risk for IBD, adding fecal calprotectin testing to alarm symptoms was the optimal strategy for improving risk stratification.

The adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) for risk stratification in young APS patients with acute myocardial infarction.

Science.gov (United States)

Radin, M; Schreiber, K; Costanzo, P; Cecchi, I; Roccatello, D; Baldovino, S; Bazzan, M; Cuadrado, M J; Sciascia, S

2017-08-01

Young adults with acute myocardial infarction are a critical group to examine for the purpose of risk factor stratification and modification. In this study we aimed to assess the clinical utility of the adjusted Global AntiphosPholipid Syndrome Score (aGAPSS) for the risk stratification of acute myocardial infarction in a cohort of young patients with antiphospholipid syndrome (APS). The analysis included 83 consecutive APS patients (≤50years old) who presented with arterial or venous thromboembolic events. Data on cardiovascular risk factors and antiphospholipid antibodies (aPL) positivity were retrospectively collected. The aGAPSS was calculated by adding the points corresponding to the risk factors, based on a linear transformation derived from the ß-regression coefficient as follows: 3 for hyperlipidaemia, 1 for arterial hypertension, 5 for aCL IgG/IgM, 4 for anti-b2 glycoprotein I IgG/IgM and 4 for LA. Higher aGAPSS values were observed in patients with acute myocardial infarction when compared to the others [mean aGAPSS 11.9 (S.D. 4.15, range 4-18) Vs. mean aGAPSS 9.2 (S.D. 5.1, range 1-17); T test: psyndrome compared to patients with a history of peripheral or cerebrovascular arterial thrombotic events [mean aGAPSS 11.9 (S.D. 4.15, range 4-18) Vs. mean aGAPSS 6.7 (S.D. 5.7, range 1-17); T test: P<0.005]. The aGAPSS is based upon a quantitative score and could aid risk stratifying APS patients younger than 50years for the likelihood of developing coronary thrombotic events and may guide pharmacological treatment for high-risk patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Impact of chromosome alterations, genetic mutations and clonal hematopoiesis of indeterminate potential (CHIP) on the classification and risk stratification of MDS.

Science.gov (United States)

Ganguly, Bani Bandana; Banerjee, Debasis; Agarwal, Mohan B

2018-03-01

The advent of technological development has undoubtedly advanced biological and molecular inputs for better understanding the heterogeneous hematopoietic pre-malignant disorder of the stem cells known as myelodysplastic syndromes (MDS). Chromosomal rearrangements, including del(3q/5q/7q/11q/12p/20q), loss of 5/7/Y, trisomy 8/19, i(17q), etc. frequently detected in MDS with variable frequencies and combinations, are the integral components of the 5-tier risk-stratification and WHO-2016 classification. Observations on mutations in genes involved in RNA-splicing, DNA methylation, chromatin modification, transcription factor, signal transduction/kinases, RAS pathway, cohesin complex, DNA repair and other pathways have given insights in independent effects and biological interaction of co-occurrence on disease-phenotype and treatment outcome. However, recent concepts of clonal hematopoiesis of indeterminate potential (CHIP) and idiopathic cytopenia of undetermined significance (ICUS) have urged a re-definition of mutational events in non-clonal cytopenia and non-MDS healthy elderly but with a higher risk of overt leukemia. Considering gene mutations, chromosomal alterations, CHIP, ICUS and their significance in classification and risk-scoring certainly presents a comprehensive picture of disease-phenotype towards better understanding of MDS-pathogenesis, its evolution to AML and its response to therapeutic agents. The present review summarizes chromosomal and gene mutations, co-existence of mutational complexity, and WHO-2016 classification and risk-stratifications of MDS to facilitate a better understanding of its pathogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

Predictors of biochemical failure in patients undergoing prostate whole-gland salvage cryotherapy: a novel risk stratification model.

Science.gov (United States)

Spiess, Philippe E; Levy, David A; Mouraviev, Vladimir; Pisters, Louis L; Jones, J Stephen

2013-08-01

What's known on the subject? and what does the study add?: Previous studies have identified the most important prognostic factors of the likely outcomes of salvage prostate whole-gland ablation, including initial clinical stage, biopsy Gleason score, and PSA (total and doubling time). There is potential for further optimization of candidate selection for salvage cryoablation with curative intent and nadir PSA achieved after whole-gland cryotherapy may provide additional prognostic value. The study shows that the most important prognostic factors of biochemical progression-free survival for patients who have undergone whole-gland salvage prostate cryotherapy are nadir PSA achieved after therapy and pre-therapy biopsy Gleason score. Based on these two prognostic variables, we have identified risk stratification groups (low, intermediate and high) which help predict the expected outcomes of salvage whole-gland prostate cryotherapy in a given patient. This risk stratification constitutes a useful clinical tool in defining which patients maybe best suited for this local salvage treatment method. To assess the prognostic variables predicting the risk of biochemical progression-free survival (bPFS) after salvage prostate whole-gland cryotherapy using the Phoenix definition of bPFS. A total of 132 patients underwent prostate whole-gland salvage cryotherapy with curative intent. No patient underwent neoadjuvant/adjuvant hormonal ablative therapy, and all had extended post-salvage prostate-specific antigen (PSA) follow-up data. Cox univariate and multivariate logistic regression analyses of potential predictors of bPFS were conducted. Kaplan-Meier analyses of bPFS was also performed. At a mean (range) follow-up of 4.3 (0.9-12.7) years, the median (range) post-cryotherapy nadir PSA achieved was 0.17 (0-33.9) ng/mL. On multivariate analysis, predictors of bPFS were nadir PSA post-cryotherapy and pre-salvage biopsy Gleason score (P 2.5 ng/mL or biopsy Gleason score ≥ 7, with

Combustion stratification study of partially premixed combustion using Fourier transform analysis of OH* chemiluminescence images

KAUST Repository

Izadi Najafabadi, Mohammad

2017-11-06

A relatively high level of stratification (qualitatively: lack of homogeneity) is one of the main advantages of partially premixed combustion over the homogeneous charge compression ignition concept. Stratification can smooth the heat release rate and improve the controllability of combustion. In order to compare stratification levels of different partially premixed combustion strategies or other combustion concepts, an objective and meaningful definition of “stratification level” is required. Such a definition is currently lacking; qualitative/quantitative definitions in the literature cannot properly distinguish various levels of stratification. The main purpose of this study is to objectively define combustion stratification (not to be confused with fuel stratification) based on high-speed OH* chemiluminescence imaging, which is assumed to provide spatial information regarding heat release. Stratification essentially being equivalent to spatial structure, we base our definition on two-dimensional Fourier transforms of photographs of OH* chemiluminescence. A light-duty optical diesel engine has been used to perform the OH* bandpass imaging on. Four experimental points are evaluated, with injection timings in the homogeneous regime as well as in the stratified partially premixed combustion regime. Two-dimensional Fourier transforms translate these chemiluminescence images into a range of spatial frequencies. The frequency information is used to define combustion stratification, using a novel normalization procedure. The results indicate that this new definition, based on Fourier analysis of OH* bandpass images, overcomes the drawbacks of previous definitions used in the literature and is a promising method to compare the level of combustion stratification between different experiments.

Combustion Stratification for Naphtha from CI Combustion to PPC

KAUST Repository

Vallinayagam, R.

2017-03-28

This study demonstrates the combustion stratification from conventional compression ignition (CI) combustion to partially premixed combustion (PPC). Experiments are performed in an optical CI engine at a speed of 1200 rpm for diesel and naphtha (RON = 46). The motored pressure at TDC is maintained at 35 bar and fuelMEP is kept constant at 5.1 bar to account for the difference in fuel properties between naphtha and diesel. Single injection strategy is employed and the fuel is injected at a pressure of 800 bar. Photron FASTCAM SA4 that captures in-cylinder combustion at the rate of 10000 frames per second is employed. The captured high speed video is processed to study the combustion homogeneity based on an algorithm reported in previous studies. Starting from late fuel injection timings, combustion stratification is investigated by advancing the fuel injection timings. For late start of injection (SOI), a direct link between SOI and combustion phasing is noticed. At early SOI, combustion phasing depends on both intake air temperature and SOI. In order to match the combustion phasing (CA50) of diesel, the intake air temperature is increased to 90°C for naphtha. The combustion stratification from CI to PPC is also investigated for various level of dilution by displacing oxygen with nitrogen in the intake. The start of combustion (SOC) was delayed with the increase in dilution and to compensate for this, the intake air temperature is increased. The mixture homogeneity is enhanced for higher dilution due to longer ignition delay. The results show that high speed image is initially blue and then turned yellow, indicating soot formation and oxidation. The luminosity of combustion images decreases with early SOI and increased dilution. The images are processed to generate the level of stratification based on the image intensity. The level of stratification is same for diesel and naphtha at various SOI. When O concentration in the intake is decreased to 17.7% and 14

Risk Stratification and Effects of Pharmacotherapy in Patients with Acute Myocardial Infarction (AMI) based on data from Pilot AMI Registry

Czech Academy of Sciences Publication Activity Database

Peleška, Jan; Grünfeldová, H.; Monhart, Z.; Faltus, Václav; Tomečková, Marie; Ryšavá, D.; Velimský, T.; Ballek, L.; Hubač, J.; Charalampidi, K.; Jánský, P.

2007-01-01

Roč. 30 (2007), s. 367-367 ISSN 1420-4096. [Central European Meeting on Hypertension and Cardiovascular Disease Prevention. 11.10.2007-13.10.2007, Kraków] R&D Projects: GA MŠk(CZ) 1M06014 Institutional research plan: CEZ:AV0Z10300504 Keywords : pilot registry of acute myocardial infarction * risk stratification in acute myocardial infarction * effects of pharmacotherapy in acute myocardial infarction Subject RIV: FA - Cardiovascular Disease s incl. Cardiotharic Surgery

On Optimum Stratification

OpenAIRE

M. G. M. Khan; V. D. Prasad; D. K. Rao

2014-01-01

In this manuscript, we discuss the problem of determining the optimum stratification of a study (or main) variable based on the auxiliary variable that follows a uniform distribution. If the stratification of survey variable is made using the auxiliary variable it may lead to substantial gains in precision of the estimates. This problem is formulated as a Nonlinear Programming Problem (NLPP), which turn out to multistage decision problem and is solved using dynamic programming technique.

The risk stratification and prognostic evaluation of soluble programmed death-1 on patients with sepsis in emergency department.

Science.gov (United States)

Zhao, Yongzhen; Jia, Yumei; Li, Chunsheng; Fang, Yingying; Shao, Rui

2018-01-01

To evaluate the efficacy of soluble programmed death-1 (sPD-1) for risk stratification and prediction of 28-day mortality in patients with sepsis, we compared serum sPD-1 with procalcitonin (PCT), C-reactive protein (CRP), and the Mortality in Emergency Department Sepsis (MEDS) score. A total of 60 healthy volunteers and 595 emergency department (ED) patients were recruited for this prospective cohort study. According to the severity of their condition on ED arrival, the patients were allocated to the systemic inflammatory response syndrome group (130 cases), sepsis group (276 cases), severe sepsis group (121 cases), and septic shock group (68 cases). In addition, all patients with sepsis were also divided into the survivor group (349 cases) and nonsurvivor group (116 cases) according to the 28-day outcomes. When the severity of sepsis increased, the levels of sPD-1 gradually increased. The levels of sPD-1, PCT, CRP and the MEDS score were also higher in the nonsurvivor group compared to the survivor group. Logistic regression suggested that sPD-1, PCT, and the MEDS score were independent risk factors for 28-day mortality of patients with sepsis. Area under the curve (AUC) of sPD-1, PCT and the MEDS score for 28-day mortality was 0.725, 0.693, and 0.767, respectively, and the AUC was improved when all 3 factors were combined (0.843). Serum sPD-1 is positively correlated with the severity of sepsis, and it is valuable for risk stratification of patients and prediction of 28-day mortality. Combining sPD-1 with PCT and the MEDS score improves the prognostic evaluation. Copyright © 2017 Elsevier Inc. All rights reserved.

BAYESIAN BICLUSTERING FOR PATIENT STRATIFICATION.

Science.gov (United States)

Khakabimamaghani, Sahand; Ester, Martin

2016-01-01

The move from Empirical Medicine towards Personalized Medicine has attracted attention to Stratified Medicine (SM). Some methods are provided in the literature for patient stratification, which is the central task of SM, however, there are still significant open issues. First, it is still unclear if integrating different datatypes will help in detecting disease subtypes more accurately, and, if not, which datatype(s) are most useful for this task. Second, it is not clear how we can compare different methods of patient stratification. Third, as most of the proposed stratification methods are deterministic, there is a need for investigating the potential benefits of applying probabilistic methods. To address these issues, we introduce a novel integrative Bayesian biclustering method, called B2PS, for patient stratification and propose methods for evaluating the results. Our experimental results demonstrate the superiority of B2PS over a popular state-of-the-art method and the benefits of Bayesian approaches. Our results agree with the intuition that transcriptomic data forms a better basis for patient stratification than genomic data.

Fundamental Interactions in Gasoline Compression Ignition Engines with Fuel Stratification

Science.gov (United States)

Wolk, Benjamin Matthew

Transportation accounted for 28% of the total U.S. energy demand in 2011, with 93% of U.S. transportation energy coming from petroleum. The large impact of the transportation sector on global climate change necessitates more-efficient, cleaner-burning internal combustion engine operating strategies. One such strategy that has received substantial research attention in the last decade is Homogeneous Charge Compression Ignition (HCCI). Although the efficiency and emissions benefits of HCCI are well established, practical limits on the operating range of HCCI engines have inhibited their application in consumer vehicles. One such limit is at high load, where the pressure rise rate in the combustion chamber becomes excessively large. Fuel stratification is a potential strategy for reducing the maximum pressure rise rate in HCCI engines. The aim is to introduce reactivity gradients through fuel stratification to promote sequential auto-ignition rather than a bulk-ignition, as in the homogeneous case. A gasoline-fueled compression ignition engine with fuel stratification is termed a Gasoline Compression Ignition (GCI) engine. Although a reasonable amount of experimental research has been performed for fuel stratification in GCI engines, a clear understanding of how the fundamental in-cylinder processes of fuel spray evaporation, mixing, and heat release contribute to the observed phenomena is lacking. Of particular interest is gasoline's pressure sensitive low-temperature chemistry and how it impacts the sequential auto-ignition of the stratified charge. In order to computationally study GCI with fuel stratification using three-dimensional computational fluid dynamics (CFD) and chemical kinetics, two reduced mechanisms have been developed. The reduced mechanisms were developed from a large, detailed mechanism with about 1400 species for a 4-component gasoline surrogate. The two versions of the reduced mechanism developed in this work are: (1) a 96-species version and (2

A clinical risk stratification tool for predicting treatment resistance in major depressive disorder.

Science.gov (United States)

Perlis, Roy H

2013-07-01

Early identification of depressed individuals at high risk for treatment resistance could be helpful in selecting optimal setting and intensity of care. At present, validated tools to facilitate this risk stratification are rarely used in psychiatric practice. Data were drawn from the first two treatment levels of a multicenter antidepressant effectiveness study in major depressive disorder, the STAR*D (Sequenced Treatment Alternatives to Relieve Depression) cohort. This cohort was divided into training, testing, and validation subsets. Only clinical or sociodemographic variables available by or readily amenable to self-report were considered. Multivariate models were developed to discriminate individuals reaching remission with a first or second pharmacological treatment trial from those not reaching remission despite two trials. A logistic regression model achieved an area under the receiver operating characteristic curve exceeding .71 in training, testing, and validation cohorts and maintained good calibration across cohorts. Performance of three alternative models with machine learning approaches--a naïve Bayes classifier and a support vector machine, and a random forest model--was less consistent. Similar performance was observed between more and less severe depression, men and women, and primary versus specialty care sites. A web-based calculator was developed that implements this tool and provides graphical estimates of risk. Risk for treatment resistance among outpatients with major depressive disorder can be estimated with a simple model incorporating baseline sociodemographic and clinical features. Future studies should examine the performance of this model in other clinical populations and its utility in treatment selection or clinical trial design. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Beyond pulmonary edema: diagnostic, risk stratification, and treatment challenges of acute heart failure management in the emergency department.

Science.gov (United States)

Collins, Sean; Storrow, Alan B; Kirk, J Douglas; Pang, Peter S; Diercks, Deborah B; Gheorghiade, Mihai

2008-01-01

The majority of heart failure hospitalizations in the United States originate in the emergency department (ED). Current strategies for acute heart failure syndromes have largely been tailored after chronic heart failure guidelines and care. Prospective ED-based acute heart failure syndrome trials are lacking, and current guidelines for disposition are based on either little or no evidence. As a result, the majority of ED acute heart failure syndrome patients are admitted to the hospital. Recent registry data suggest there is a significant amount of heterogeneity in acute heart failure syndrome ED presentations, and diagnostics and therapeutics may need to be individualized to the urgency of the presentation, underlying pathophysiology, and acute hemodynamic characteristics. A paradigm shift is necessary in acute heart failure syndrome guidelines and research: prospective trials need to focus on diagnostic, therapeutic, and risk-stratification algorithms that rely on readily available ED data, focusing on outcomes more proximate to the ED visit (5 days). Intermediate outcomes (30 days) are more dependent on inpatient and outpatient care and patient behavior than ED management decisions. Without these changes, the burden of acute heart failure syndrome care is unlikely to change. This article proposes such a paradigm shift in acute heart failure syndrome care and discusses areas of further research that are necessary to promote this change in approach.

Thermal stratification in the pressurizer

International Nuclear Information System (INIS)

Baik, S.J.; Lee, K.W.; Ro, T.S.

2001-01-01

The thermal stratification in the pressurizer due to the insurge from the hot leg to the pressurizer has been studied. The insurge flow of the cold water into the pressurizer takes place during the heatup/cooldown and the normal or abnormal transients during power operation. The pressurizer vessel can undergo significant thermal fatigue usage caused by insurges and outsurges. Two-dimensional axisymmetric transient analysis for the thermal stratification in the pressurizer is performed using the computational fluid dynamics code, FLUENT, to get the velocity and temperature distribution. Parametric study has been carried out to investigate the effect of the inlet velocity and the temperature difference between the hot leg and the pressurizer on the thermal stratification. The results show that the insurge flow of cold water into the pressurizer does not mix well with hot water, and the cold water remains only in the lower portion of the pressurizer, which leads to the thermal stratification in the pressurizer. The thermal load on the pressurizer due to the thermal stratification or the cyclic thermal transient should be examined with respect to the mechanical integrity and this study can serve the design data for the stress analysis. (authors)

Existential risks: exploring a robust risk reduction strategy.

Science.gov (United States)

Jebari, Karim

2015-06-01

A small but growing number of studies have aimed to understand, assess and reduce existential risks, or risks that threaten the continued existence of mankind. However, most attention has been focused on known and tangible risks. This paper proposes a heuristic for reducing the risk of black swan extinction events. These events are, as the name suggests, stochastic and unforeseen when they happen. Decision theory based on a fixed model of possible outcomes cannot properly deal with this kind of event. Neither can probabilistic risk analysis. This paper will argue that the approach that is referred to as engineering safety could be applied to reducing the risk from black swan extinction events. It will also propose a conceptual sketch of how such a strategy may be implemented: isolated, self-sufficient, and continuously manned underground refuges. Some characteristics of such refuges are also described, in particular the psychosocial aspects. Furthermore, it is argued that this implementation of the engineering safety strategy safety barriers would be effective and plausible and could reduce the risk of an extinction event in a wide range of possible (known and unknown) scenarios. Considering the staggering opportunity cost of an existential catastrophe, such strategies ought to be explored more vigorously.

Estratificación de riesgo en pie diabético Risk stratification in diabetic foot

Directory of Open Access Journals (Sweden)

Héctor González de la Torre

2010-12-01

factors is an essential previous step in nursing. The purpose of this study is to detect the presence of certain risk factors in diabetic foot in the diabetic population of Triana Healthcare Centre to be able to carry out a stratification of the risk. For this research, there was chosen an observational, descriptive and transversal study. The analyzed sample was constituted by 96 diabetic subjects belonging to the Healthcare Centre. For the data collection, we use different systems such as interviews, physical exams and the available records (clinical history of the patients. The information has been recorded in a questionnaire of the diabetic foot. The existence of risk factors was determined by analyzing the relationship between them allowing the risk stratification of the studied sample.

Multilayer fabric stratification pipes for solar tanks

DEFF Research Database (Denmark)

Andersen, Elsa; Furbo, Simon; Fan, Jianhua

2007-01-01

The thermal performance of solar heating systems is strongly influenced by the thermal stratification in the heat storage. The higher the degree of thermal stratification is, the higher the thermal performance of the solar heating systems. Thermal stratification in water storages can for instance...

Diagnostic performance of an acoustic-based system for coronary artery disease risk stratification.

Science.gov (United States)

Winther, Simon; Nissen, Louise; Schmidt, Samuel Emil; Westra, Jelmer Sybren; Rasmussen, Laust Dupont; Knudsen, Lars Lyhne; Madsen, Lene Helleskov; Kirk Johansen, Jane; Larsen, Bjarke Skogstad; Struijk, Johannes Jan; Frost, Lars; Holm, Niels Ramsing; Christiansen, Evald Høj; Botker, Hans Erik; Bøttcher, Morten

2017-11-09

Diagnosing coronary artery disease (CAD) continues to require substantial healthcare resources. Acoustic analysis of transcutaneous heart sounds of cardiac movement and intracoronary turbulence due to obstructive coronary disease could potentially change this. The aim of this study was thus to test the diagnostic accuracy of a new portable acoustic device for detection of CAD. We included 1675 patients consecutively with low to intermediate likelihood of CAD who had been referred for cardiac CT angiography. If significant obstruction was suspected in any coronary segment, patients were referred to invasive angiography and fractional flow reserve (FFR) assessment. Heart sound analysis was performed in all patients. A predefined acoustic CAD-score algorithm was evaluated; subsequently, we developed and validated an updated CAD-score algorithm that included both acoustic features and clinical risk factors. Low risk is indicated by a CAD-score value ≤20. Haemodynamically significant CAD assessed from FFR was present in 145 (10.0%) patients. In the entire cohort, the predefined CAD-score had a sensitivity of 63% and a specificity of 44%. In total, 50% had an updated CAD-score value ≤20. At this cut-off, sensitivity was 81% (95% CI 73% to 87%), specificity 53% (95% CI 50% to 56%), positive predictive value 16% (95% CI 13% to 18%) and negative predictive value 96% (95% CI 95% to 98%) for diagnosing haemodynamically significant CAD. Sound-based detection of CAD enables risk stratification superior to clinical risk scores. With a negative predictive value of 96%, this new acoustic rule-out system could potentially supplement clinical assessment to guide decisions on the need for further diagnostic investigation. ClinicalTrials.gov identifier NCT02264717; Results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Doppler Endoscopic Probe Monitoring of Blood Flow Improves Risk Stratification and Outcomes of Patients With Severe Nonvariceal Upper Gastrointestinal Hemorrhage.

Science.gov (United States)

Jensen, Dennis M; Kovacs, Thomas O G; Ohning, Gordon V; Ghassemi, Kevin; Machicado, Gustavo A; Dulai, Gareth S; Sedarat, Alireza; Jutabha, Rome; Gornbein, Jeffrey

2017-05-01

For 4 decades, stigmata of recent hemorrhage in patients with nonvariceal lesions have been used for risk stratification and endoscopic hemostasis. The arterial blood flow that underlies the stigmata rarely is monitored, but can be used to determine risk for rebleeding. We performed a randomized controlled trial to determine whether Doppler endoscopic probe monitoring of blood flow improves risk stratification and outcomes in patients with severe nonvariceal upper gastrointestinal hemorrhage. In a single-blind study performed at 2 referral centers we assigned 148 patients with severe nonvariceal upper gastrointestinal bleeding (125 with ulcers, 19 with Dieulafoy's lesions, and 4 with Mallory Weiss tears) to groups that underwent standard, visually guided endoscopic hemostasis (control, n = 76), or endoscopic hemostasis assisted by Doppler monitoring of blood flow under the stigmata (n = 72). The primary outcome was the rate of rebleeding after 30 days; secondary outcomes were complications, death, and need for transfusions, surgery, or angiography. There was a significant difference in the rates of lesion rebleeding within 30 days of endoscopic hemostasis in the control group (26.3%) vs the Doppler group (11.1%) (P = .0214). The odds ratio for rebleeding with Doppler monitoring was 0.35 (95% confidence interval, 0.143-0.8565) and the number needed to treat was 7. In a randomized controlled trial of patients with severe upper gastrointestinal hemorrhage from ulcers or other lesions, Doppler probe guided endoscopic hemostasis significantly reduced 30-day rates of rebleeding compared with standard, visually guided hemostasis. Guidelines for nonvariceal gastrointestinal bleeding should incorporate these results. ClinicalTrials.gov no: NCT00732212 (CLIN-013-07F). Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Talent Complementarity and Organizational Stratification

Science.gov (United States)

Abrahamson, Mark

1973-01-01

Stratification within organizations as produced by the distribution of functional importance among positions is investigated. According to Stinchcombe's hypothesis from the functional theory of stratification, the rewards given to various positions are expected to be less equal when talent is complementary rather than additive. Actual differences…

Risk stratification of cardiovascular events in hypertensive patients with asymptomatic or symptomatic lacunar infarcts by 24-hour ambulatory blood pressure monitoring

International Nuclear Information System (INIS)

Shiraishi, Makoto; Watanabe, Hirofumi; Sakurai, Kenzo; Kato, Bunta; Hasegawa, Yasuhiro

2012-01-01

Our goal was to investigate the utility of 24-hour ambulatory blood pressure monitoring (ABPM) for the risk stratification of cardiovascular events in hypertensive patients with asymptomatic or symptomatic lacunar infarcts. A total of 175 hypertensive patients with MRI evidence of asymptomatic or symptomatic lacunar infarcts (92 men, mean age of 69±11 years old) were studied. Patients with symptomatic infarctions were included whose events occurred more than 6 months after the onset. ABPM was performed in all patients in the outpatient clinic. Parameters obtained from ABPM were related to the composite outcome which consisted of all death and fatal or non-fatal cardiovascular events by using the Cox proportional hazard model. Mean follow-up period was 4.8 years and the composite outcome was recorded in 38 patients. 34 of them (89%) had recurrence of lacunar infarcts. Significant association between sleep-time lowest systolic blood pressure and composite outcome was demonstrated by multivariate Cox hazard analyses (heart rate (HR) 1.025, 95% confidence interval (CI) 1.011-1.039, p<0.001). The risk for composite outcome in patients with the highest tertile of sleep-time lowest systolic blood pressure (≥133 mmHg) was significantly elevated when compared to the lowest tertile (<132 mmHg, HR 3.93, 95% CI 1.57-9.86, p=0.004). Sleep-time lowest systolic blood pressure in ABPM may be a useful parameter for the risk stratification of future cardiovascular events in hypertensive patients with asymptomatic or symptomatic lacunar infarcts, especially for the recurrence of these events. (author)

Identifying patients at risk of intraoperative and postoperative transfusion in isolated CABG: toward selective conservation strategies.

Science.gov (United States)

Arora, Rakesh C; Légaré, Jean-Francois; Buth, Karen J; Sullivan, John A; Hirsch, Gregory M

2004-11-01

Allogeneic blood product use during cardiac operation is often reported to exceed 40% despite published guidelines and costly blood conservation strategies. We developed a predictive model, based on eight preoperative risk factors, of allogeneic blood product transfusion rates in patients undergoing a cardiac procedure. All 3,046 consecutive, isolated coronary artery bypass graft (CABG) procedures at a university hospital from 1995 to 1998 were included. A logistic regression model was created to identify independent predictors of allogeneic blood product transfusion. This model was validated using a prospective patient sample. Overall use of allogeneic blood products was 23% with a crude operative mortality of 2.1%. In isolated, elective, first-time CABG cases, 16.9% received allogeneic blood products. Independent predictors of blood product usage in CABG patients were preoperative hemoglobin 12.0 or less, emergent operation, renal failure, female sex, age 70 years or older, left ventricular ejection fraction 0.40 or less, redo procedure, and low body surface area. Prospective validation of this model on 2,117 consecutive isolated CABG patients demonstrated an observed-to-expected allogeneic blood product transfusion rate ratio of 1.06. This internally validated logistic regression risk model is a sensitive and specific predictor of allogeneic blood product use in patients undergoing isolated CABG. Utilization of this model allows for preoperative risk stratification and may allow for more rational resource allocation of costly blood conservation strategies and blood bank resources.

Prognostic stratification of acute pulmonary embolism: Focus on clinical aspects, imaging, and biomarkers

Directory of Open Access Journals (Sweden)

Luca Masotti

2009-07-01

Full Text Available Luca Masotti1, Marc Righini2, Nicolas Vuilleumier3, Fabio Antonelli4, Giancarlo Landini5, Roberto Cappelli6, Patrick Ray71Internal Medicine, 4Clinical Chemistry, Cecina Hospital, Cecina, Italy; 2Division of Angiology and Haemostasis, Department of Internal Medicine, Geneva University Hospital, Switzerland; 3Division of Laboratory Medicine, Department of Genetics and Laboratory Medicine, Geneva University Hospitals and University of Geneva, Switzerland; 5Internal Medicine, Santa Maria Nuova Hospital, Florence, Italy; 6Thrombosis Center, University of Siena, Siena, Italy; 7Department of Emergency Medicine, Centre Hospitalo-Universitaire Pitié-Salpêtrière, UPMC Paris 6, Paris, FranceAbstract: Pulmonary embolism (PE represents a common disease in emergency medicine and guidelines for diagnosis and treatment have had wide diffusion. However, PE morbidity and mortality remain high, especially when associated to hemodynamic instability or right ventricular dysfunction. Prognostic stratification to identify high risk patients needing to receive more aggressive pharmacological and closer monitoring is of utmost importance. Modern guidelines for management of acute PE are based on risk stratification using either clinical, radiological, or laboratory findings. This article reviews the modern treatment of acute PE, which is customized upon patient prognosis. Accordingly the current risk stratification tools described in the literature such as clinical scores, echocardiography, helical computer tomography, and biomarkers will be reviewed.Keywords: pulmonary embolism, prognosis, troponin, BNP, NT-proBNP, echocardiography, computer tomography

Public health implications from COGS and potential for risk stratification and screening.

Science.gov (United States)

Burton, Hilary; Chowdhury, Susmita; Dent, Tom; Hall, Alison; Pashayan, Nora; Pharoah, Paul

2013-04-01

The PHG Foundation led a multidisciplinary program, which used results from COGS research identifying genetic variants associated with breast, ovarian and prostate cancers to model risk-stratified prevention for breast and prostate cancers. Implementing such strategies would require attention to the use and storage of genetic information, the development of risk assessment tools, new protocols for consent and programs of professional education and public engagement.

Cardiovascular risk stratification in overweight or obese patients in primary prevention. Implications for use of statins.

Science.gov (United States)

Masson, Walter; Lobo, Martín; Huerín, Melina; Molinero, Graciela; Manente, Diego; Pángaro, Mario; Vitagliano, Laura; Zylbersztejn, Horacio

2015-02-01

Cardiovascular risk estimation in patients with overweight/obesity is not standardized. Our objectives were to stratify cardiovascular risk using different scores, to analyze use of statins, to report the prevalence of carotid atherosclerotic plaque (CAP), and to determine the optimal cut-off point (OCP) of scores that discriminate between subjects with or without CAP. Non-diabetic patients with overweight or obesity in primary prevention were enrolled. The Framingham score (FS), the European score (ES), and the score proposed by the new American guidelines (NS) were calculated, and statin indication was evaluated. Prevalence of CAP was determined by ultrasound examination. A ROC analysis was performed. A total of 474 patients (67% with overweight and 33% obese) were enrolled into the study. The FS classified the largest number of subjects as low risk. PAC prevalence was higher in obese as compared to overweight subjects (44.8% vs. 36.1%, P=.04). According to the FS, ES, and NS respectively, 26.7%, 39.1%, and 39.1% of overweight subjects and 28.6%, 39.0%, and 39.0% of obese subjects had an absolute indication for statins. All three scores were shown to acceptably discriminate between subjects with and without CAP (area under the curve>0.7). The OCPs evaluated did not agree with the risk category values. Risk stratification and use of statins varied in the overweight/obese population depending on the function used. Understanding of the relationship between scores and presence of CAP may optimize risk estimate. Copyright © 2014 SEEN. Published by Elsevier España, S.L.U. All rights reserved.

The MARINA Risk Assessment Strategy: A Flexible Strategy for Efficient Information Collection and Risk Assessment of Nanomaterials.

Science.gov (United States)

Bos, Peter M J; Gottardo, Stefania; Scott-Fordsmand, Janeck J; van Tongeren, Martie; Semenzin, Elena; Fernandes, Teresa F; Hristozov, Danail; Hund-Rinke, Kerstin; Hunt, Neil; Irfan, Muhammad-Adeel; Landsiedel, Robert; Peijnenburg, Willie J G M; Sánchez Jiménez, Araceli; van Kesteren, Petra C E; Oomen, Agnes G

2015-11-27

An engineered nanomaterial (ENM) may actually consist of a population of primary particles, aggregates and agglomerates of various sizes. Furthermore, their physico-chemical characteristics may change during the various life-cycle stages. It will probably not be feasible to test all varieties of all ENMs for possible health and environmental risks. There is therefore a need to further develop the approaches for risk assessment of ENMs. Within the EU FP7 project Managing Risks of Nanoparticles (MARINA) a two-phase risk assessment strategy has been developed. In Phase 1 (Problem framing) a base set of information is considered, relevant exposure scenarios (RESs) are identified and the scope for Phase 2 (Risk assessment) is established. The relevance of an RES is indicated by information on exposure, fate/kinetics and/or hazard; these three domains are included as separate pillars that contain specific tools. Phase 2 consists of an iterative process of risk characterization, identification of data needs and integrated collection and evaluation of data on the three domains, until sufficient information is obtained to conclude on possible risks in a RES. Only data are generated that are considered to be needed for the purpose of risk assessment. A fourth pillar, risk characterization, is defined and it contains risk assessment tools. This strategy describes a flexible and efficient approach for data collection and risk assessment which is essential to ensure safety of ENMs. Further developments are needed to provide guidance and make the MARINA Risk Assessment Strategy operational. Case studies will be needed to refine the strategy.

The MARINA Risk Assessment Strategy: A Flexible Strategy for Efficient Information Collection and Risk Assessment of Nanomaterials

Directory of Open Access Journals (Sweden)

Peter M. J. Bos

2015-11-01

Full Text Available An engineered nanomaterial (ENM may actually consist of a population of primary particles, aggregates and agglomerates of various sizes. Furthermore, their physico-chemical characteristics may change during the various life-cycle stages. It will probably not be feasible to test all varieties of all ENMs for possible health and environmental risks. There is therefore a need to further develop the approaches for risk assessment of ENMs. Within the EU FP7 project Managing Risks of Nanoparticles (MARINA a two-phase risk assessment strategy has been developed. In Phase 1 (Problem framing a base set of information is considered, relevant exposure scenarios (RESs are identified and the scope for Phase 2 (Risk assessment is established. The relevance of an RES is indicated by information on exposure, fate/kinetics and/or hazard; these three domains are included as separate pillars that contain specific tools. Phase 2 consists of an iterative process of risk characterization, identification of data needs and integrated collection and evaluation of data on the three domains, until sufficient information is obtained to conclude on possible risks in a RES. Only data are generated that are considered to be needed for the purpose of risk assessment. A fourth pillar, risk characterization, is defined and it contains risk assessment tools. This strategy describes a flexible and efficient approach for data collection and risk assessment which is essential to ensure safety of ENMs. Further developments are needed to provide guidance and make the MARINA Risk Assessment Strategy operational. Case studies will be needed to refine the strategy.

Comparison of accuracy of diabetes risk score and components of the metabolic syndrome in assessing risk of incident type 2 diabetes in Inter99 cohort.

Directory of Open Access Journals (Sweden)

Tracy B Shafizadeh

Full Text Available BACKGROUND: Given the increasing worldwide incidence of diabetes, methods to assess diabetes risk which would identify those at highest risk are needed. We compared two risk-stratification approaches for incident type 2 diabetes mellitus (T2DM; factors of metabolic syndrome (MetS and a previously developed diabetes risk score, PreDx® Diabetes Risk Score (DRS. DRS assesses 5 yr risk of incident T2DM based on the measurement of 7 biomarkers in fasting blood. METHODOLOGY/PRINCIPAL FINDINGS: DRS was evaluated in baseline serum samples from 4,128 non-diabetic subjects in the Inter99 cohort (Danes aged 30-60 for whom diabetes outcomes at 5 years were known. Subjects were classified as having MetS based on the presence of at least 3 MetS risk factors in baseline clinical data. The sensitivity and false positive rate for predicting diabetes using MetS was compared to DRS. When the sensitivity was fixed to match MetS, DRS had a significantly lower false positive rate. Similarly, when the false positive rate was fixed to match MetS, DRS had a significantly higher specificity. In further analyses, subjects were classified by presence of 0-2, 3 or 4-5 risk factors with matching proportions of subjects distributed among three DRS groups. Comparison between the two risk stratification schemes, MetS risk factors and DRS, were evaluated using Net Reclassification Improvement (NRI. Comparing risk stratification by DRS to MetS factors in the total population, the NRI was 0.146 (p = 0.008 demonstrating DRS provides significantly improved stratification. Additionally, the relative risk of T2DM differed by 15 fold between the low and high DRS risk groups, but only 8-fold between the low and high risk MetS groups. CONCLUSIONS/SIGNIFICANCE: DRS provides a more accurate assessment of risk for diabetes than MetS. This improved performance may allow clinicians to focus preventive strategies on those most in need of urgent intervention.

Optimizing risk stratification in heart failure and the selection of candidates for heart transplantation.

Science.gov (United States)

Pereira-da-Silva, Tiago; M Soares, Rui; Papoila, Ana Luísa; Pinto, Iola; Feliciano, Joana; Almeida-Morais, Luís; Abreu, Ana; Cruz Ferreira, Rui

2018-02-01

Selecting patients for heart transplantation is challenging. We aimed to identify the most important risk predictors in heart failure and an approach to optimize the selection of candidates for heart transplantation. Ambulatory patients followed in our center with symptomatic heart failure and left ventricular ejection fraction ≤40% prospectively underwent a comprehensive baseline assessment including clinical, laboratory, electrocardiographic, echocardiographic, and cardiopulmonary exercise testing parameters. All patients were followed for 60 months. The combined endpoint was cardiac death, urgent heart transplantation or need for mechanical circulatory support, up to 36 months. In the 263 enrolled patients (75% male, age 54±12 years), 54 events occurred. The independent predictors of adverse outcome were ventilatory efficiency (VE/VCO 2 ) slope (HR 1.14, 95% CI 1.11-1.18), creatinine level (HR 2.23, 95% CI 1.14-4.36), and left ventricular ejection fraction (HR 0.96, 95% CI 0.93-0.99). VE/VCO 2 slope was the most accurate risk predictor at any follow-up time analyzed (up to 60 months). The threshold of 39.0 yielded high specificity (97%), discriminated a worse or better prognosis than that reported for post-heart transplantation, and outperformed peak oxygen consumption thresholds of 10.0 or 12.0 ml/kg/min. For low-risk patients (VE/VCO 2 slope <39.0), sodium and creatinine levels and variations in end-tidal carbon dioxide partial pressure on exercise identified those with excellent prognosis. VE/VCO 2 slope was the most accurate parameter for risk stratification in patients with heart failure and reduced ejection fraction. Those with VE/VCO 2 slope ≥39.0 may benefit from heart transplantation. Copyright © 2018 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

Thermal Stratification in Vertical Mantle Tanks

DEFF Research Database (Denmark)

Knudsen, Søren; Furbo, Simon

2001-01-01

It is well known that it is important to have a high degree of thermal stratification in the hot water storage tank to achieve a high thermal performance of SDHW systems. This study is concentrated on thermal stratification in vertical mantle tanks. Experiments based on typical operation conditions...... are carried out to investigate how the thermal stratification is affected by different placements of the mantle inlet. The heat transfer between the solar collector fluid in the mantle and the domestic water in the inner tank is analysed by CFD-simulations. Furthermore, the flow pattern in the vertical mantle...

A Comparative Review of Stratification Texts and Readers

Science.gov (United States)

Peoples, Clayton D.

2012-01-01

Social stratification is a core substantive area within sociology. There are a number of textbooks and readers available on the market that deal with this central topic. In this article, I conduct a comparative review of (a) four stratification textbooks and (b) four stratification readers. (Contains 2 tables.)

Stratification studies in components of nuclear power plants

International Nuclear Information System (INIS)

Randorf, J.A.

1997-01-01

The applicability of two stratification criteria during loss-of-coolant (LOCA) conditions was studied. The first criteria was developed for addressing cold water injection-induced stratification. The second criteria applied to downcomer/cold leg junction stratification. Both criteria provided predictions consistent with measured conditions during small break loss-of-coolant tests

AN EVALUATION OF RISK MANAGEMENT STRATEGIES FOR DAIRY FARMS

OpenAIRE

Bosch, Darrell J.; Johnson, Christian J.

1992-01-01

Variability in feed prices and crop yields are important sources of risk to dairy farmers. A simulation model of a representative dairy farm was used to evaluate crop insurance and hedging as risk management strategies. These strategies lowered expected net returns but also reduced risk. The preferred set of strategies at lower levels of risk aversion included hedging and crop insurance, although a base scenario in which no risk management strategies were employed was also efficient. The pref...

Effect of sample stratification on dairy GWAS results

Directory of Open Access Journals (Sweden)

Ma Li

2012-10-01

Full Text Available Abstract Background Artificial insemination and genetic selection are major factors contributing to population stratification in dairy cattle. In this study, we analyzed the effect of sample stratification and the effect of stratification correction on results of a dairy genome-wide association study (GWAS. Three methods for stratification correction were used: the efficient mixed-model association expedited (EMMAX method accounting for correlation among all individuals, a generalized least squares (GLS method based on half-sib intraclass correlation, and a principal component analysis (PCA approach. Results Historical pedigree data revealed that the 1,654 contemporary cows in the GWAS were all related when traced through approximately 10–15 generations of ancestors. Genome and phenotype stratifications had a striking overlap with the half-sib structure. A large elite half-sib family of cows contributed to the detection of favorable alleles that had low frequencies in the general population and high frequencies in the elite cows and contributed to the detection of X chromosome effects. All three methods for stratification correction reduced the number of significant effects. EMMAX method had the most severe reduction in the number of significant effects, and the PCA method using 20 principal components and GLS had similar significance levels. Removal of the elite cows from the analysis without using stratification correction removed many effects that were also removed by the three methods for stratification correction, indicating that stratification correction could have removed some true effects due to the elite cows. SNP effects with good consensus between different methods and effect size distributions from USDA’s Holstein genomic evaluation included the DGAT1-NIBP region of BTA14 for production traits, a SNP 45kb upstream from PIGY on BTA6 and two SNPs in NIBP on BTA14 for protein percentage. However, most of these consensus effects had

Novel risk stratification with time course assessment of in-hospital mortality in patients with acute heart failure.

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Takeshi Yagyu

Full Text Available Patients with acute heart failure (AHF show various clinical courses during hospitalization. We aimed to identify time course predictors of in-hospital mortality and to establish a sequentially assessable risk model.We enrolled 1,035 consecutive AHF patients into derivation (n = 597 and validation (n = 438 cohorts. For risk assessments at admission, we utilized Get With the Guidelines-Heart Failure (GWTG-HF risk scores. We examined significant predictors of in-hospital mortality from 11 variables obtained during hospitalization and developed a risk stratification model using multiple logistic regression analysis. Across both cohorts, 86 patients (8.3% died during hospitalization. Using backward stepwise selection, we identified five time-course predictors: catecholamine administration, minimum platelet concentration, maximum blood urea nitrogen, total bilirubin, and C-reactive protein levels; and established a time course risk score that could sequentially assess a patient's risk status. The addition of a time course risk score improved the discriminative ability of the GWTG-HF risk score (c-statistics in derivation and validation cohorts: 0.776 to 0.888 [p = 0.002] and 0.806 to 0.902 [p<0.001], respectively. A calibration plot revealed a good relationship between observed and predicted in-hospital mortalities in both cohorts (Hosmer-Lemeshow chi-square statistics: 6.049 [p = 0.642] and 5.993 [p = 0.648], respectively. In each group of initial low-intermediate risk (GWTG-HF risk score <47 and initial high risk (GWTG-HF risk score ≥47, in-hospital mortality was about 6- to 9-fold higher in the high time course risk score group than in the low-intermediate time course risk score group (initial low-intermediate risk group: 20.3% versus 2.2% [p<0.001], initial high risk group: 57.6% versus 8.5% [p<0.001].A time course assessment related to in-hospital mortality during the hospitalization of AHF patients can clearly categorize a patient's on

Clinical risk stratification optimizes value of biomarkers to predict new-onset heart failure in a community-based cohort.

Science.gov (United States)

Brouwers, Frank P; van Gilst, Wiek H; Damman, Kevin; van den Berg, Maarten P; Gansevoort, Ron T; Bakker, Stephan J L; Hillege, Hans L; van Veldhuisen, Dirk J; van der Harst, Pim; de Boer, Rudolf A

2014-09-01

We aim to identify and quantify the value of biomarkers for incident new-onset heart failure (HF) in a community-based cohort and subgroups based on cardiovascular risk and evaluate the prognostic value of 13 biomarkers for HF with reduced and preserved ejection fraction. Thirteen biomarkers reflecting diverse pathophysiologic domains were examined in 8569 HF-free participants in Prevention of Vascular and Renal Endstage Disease (mean age, 49 years; 50% men). Subjects were categorized in 2 risk groups based on cardiovascular history. Incremental value per biomarker was assessed using Harrell C-indices. One hundred sixty-eight subjects (2.4%) were diagnosed with new-onset HF in the low-risk group (n=6915; Framingham Risk Score, 5.9%) and 206 (12.2%) subjects in the high-risk group (n=1654; Framingham Risk Score, 18.6%). The association of natriuretic peptides, adrenomedullin, endothelin, and galectin-3 with new-onset HF was stronger in the high-risk group (all Prisk for new-onset HF between both risk groups. The best model for new-onset HF included the combination of N-terminal pro-B-type natriuretic peptide, troponin-T, and urinary albumin excretion, increasing model accuracy to 0.81 (9.5%, Prisk group. Except for a modest effect of cystatin-C, no biomarker was associated with increased risk for HF with preserved ejection fraction. Risk stratification increases the incremental value per biomarker to predict new-onset HF, especially HF with reduced ejection fraction. We suggest that routine biomarker testing should be limited to the use of natriuretic peptides and troponin-T in patients with increased cardiovascular risk. © 2014 American Heart Association, Inc.

Prognostic stratification of patients with advanced renal cell carcinoma treated with sunitinib: comparison with the Memorial Sloan-Kettering prognostic factors model

International Nuclear Information System (INIS)

Bamias, Aristotelis; Anastasiou, Ioannis; Stravodimos, Kostas; Xanthakis, Ioannis; Skolarikos, Andreas; Christodoulou, Christos; Syrigos, Kostas; Papandreou, Christos; Razi, Evangelia; Dafni, Urania; Fountzilas, George; Karadimou, Alexandra; Dimopoulos, Meletios A; Lampaki, Sofia; Lainakis, George; Malettou, Lia; Timotheadou, Eleni; Papazisis, Kostas; Andreadis, Charalambos; Kontovinis, Loukas

2010-01-01

The treatment paradigm in advanced renal cell carcinoma (RCC) has changed in the recent years. Sunitinib has been established as a new standard for first-line therapy. We studied the prognostic significance of baseline characteristics and we compared the risk stratification with the established Memorial Sloan Kettering Cancer Center (MSKCC) model. This is a retrospective analysis of patients treated in six Greek Oncology Units of HECOG. Inclusion criteria were: advanced renal cell carcinoma not amenable to surgery and treatment with Sunitinib. Previous cytokine therapy but no targeted agents were allowed. Overall survival (OS) was the major end point. Significance of prognostic factors was evaluated with multivariate cox regression analysis. A model was developed to stratify patients according to risk. One hundred and nine patients were included. Median follow up has been 15.8 months and median OS 17.1 months (95% CI: 13.7-20.6). Time from diagnosis to the start of Sunitinib (<= 12 months vs. >12 months, p = 0.001), number of metastatic sites (1 vs. >1, p = 0.003) and performance status (PS) (<= 1 vs >1, p = 0.001) were independently associated with OS. Stratification in two risk groups ('low' risk: 0 or 1 risk factors; 'high' risk: 2 or 3 risk factors) resulted in distinctly different OS (median not reached [NR] vs. 10.8 [95% confidence interval (CI): 8.3-13.3], p < 0.001). The application of the MSKCC risk criteria resulted in stratification into 3 groups (low and intermediate and poor risk) with distinctly different prognosis underlying its validity. Nevertheless, MSKCC model did not show an improved prognostic performance over the model developed by this analysis. Studies on risk stratification of patients with advanced RCC treated with targeted therapies are warranted. Our results suggest that a simpler than the MSKCC model can be developed. Such models should be further validated

Risk Assessment and Integration Team (RAIT) Portfolio Risk Analysis Strategy

Science.gov (United States)

Edwards, Michelle

2010-01-01

Impact at management level: Qualitative assessment of risk criticality in conjunction with risk consequence, likelihood, and severity enable development of an "investment policy" towards managing a portfolio of risks. Impact at research level: Quantitative risk assessments enable researchers to develop risk mitigation strategies with meaningful risk reduction results. Quantitative assessment approach provides useful risk mitigation information.

Formalized search strategies for human risk contributions

International Nuclear Information System (INIS)

Rasmussen, J.; Pedersen, O.M.

1982-07-01

For risk management, the results of a probabilistic risk analysis (PRA) as well as the underlying assumptions can be used as references in a closed-loop risk control; and the analyses of operational experiences as a means of feedback. In this context, the need for explicit definition and documentation of the PRA coverage, including the search strategies applied, is discussed and aids are proposed such as plant description in terms of a formal abstraction hierarchy and use of cause-consequence-charts for the documentation of not only the results of PRA but also of its coverage. Typical human risk contributions are described on the basis of general plant design features relevant for risk and accident analysis. With this background, search strategies for human risk contributions are treated: Under the designation ''work analysis'', procedures for the analysis of familiar, well trained, planned tasks are proposed. Strategies for identifying human risk contributions outside this category are outlined. (author)

Strategies for successful software development risk management

Directory of Open Access Journals (Sweden)

Marija Boban

2003-01-01

Full Text Available Nowadays, software is becoming a major part of enterprise business. Software development is activity connected with advanced technology and high level of knowledge. Risks on software development projects must be successfully mitigated to produce successful software systems. Lack of a defined approach to risk management is one of the common causes for project failures. To improve project chances for success, this work investigates common risk impact areas to perceive a foundation that can be used to define a common approach to software risk management. Based on typical risk impact areas on software development projects, we propose three risk management strategies suitable for a broad area of enterprises and software development projects with different amounts of connected risks. Proposed strategies define activities that should be performed for successful risk management, the one that will enable software development projects to perceive risks as soon as possible and to solve problems connected with risk materialization. We also propose a risk-based approach to software development planning and risk management as attempts to address and retire the highest impact risks as early as possible in the development process. Proposed strategies should improve risk management on software development projects and help create a successful software solution.

Stratification devices

DEFF Research Database (Denmark)

Andersen, Elsa; Furbo, Simon

2008-01-01

Thermal stratification in the storage tank is extremely important in order to achieve high thermal performance of a solar heating system. High temperatures in the top of the storage tank and low temperatures in the bottom of the storage tank lead to the best operation conditions for any solar hea...

Formalized Search Strategies for Human Risk Contributions

DEFF Research Database (Denmark)

Rasmussen, Jens; Pedersen, O. M.

For risk management, the results of a probabilistic risk analysis (PRA) as well as the underlying assumptions can be used as references in a closed-loop risk control; and the analyses of operational experiences as a means of feedback. In this context, the need for explicit definition...... risk contributions are described on the basis of general plant design features relevant for risk and accident analysis. With this background, search strategies for human risk contributions are treated: Under the designation "work analysis", procedures for the analysis of familiar, well trained, planned...... tasks are proposed. Strategies for identifying human risk contributions outside this category are outlined....

Dynamo Tests for Stratification Below the Core-Mantle Boundary

Science.gov (United States)

Olson, P.; Landeau, M.

2017-12-01

Evidence from seismology, mineral physics, and core dynamics points to a layer with an overall stable stratification in the Earth's outer core, possibly thermal in origin, extending below the core-mantle boundary (CMB) for several hundred kilometers. In contrast, energetic deep mantle convection with elevated heat flux implies locally unstable thermal stratification below the CMB in places, consistent with interpretations of non-dipole geomagnetic field behavior that favor upwelling flows below the CMB. Here, we model the structure of convection and magnetic fields in the core using numerical dynamos with laterally heterogeneous boundary heat flux in order to rationalize this conflicting evidence. Strongly heterogeneous boundary heat flux generates localized convection beneath the CMB that coexists with an overall stable stratification there. Partially stratified dynamos have distinctive time average magnetic field structures. Without stratification or with stratification confined to a thin layer, the octupole component is small and the CMB magnetic field structure includes polar intensity minima. With more extensive stratification, the octupole component is large and the magnetic field structure includes intense patches or high intensity lobes in the polar regions. Comparisons with the time-averaged geomagnetic field are generally favorable for partial stratification in a thin layer but unfavorable for stratification in a thick layer beneath the CMB.

Usefulness of semiquantitative analysis of dipyridamole-thallium-201 redistribution for improving risk stratification before vascular surgery

International Nuclear Information System (INIS)

Levinson, J.R.; Boucher, C.A.; Coley, C.M.; Guiney, T.E.; Strauss, H.W.; Eagle, K.A.

1990-01-01

Preoperative dipyridamole-thallium-201 scanning is sensitive in identifying patients prone to ischemic cardiac complications after vascular surgery, but most patients with redistribution do not have an event after surgery. Therefore, its positive predictive value is limited. To determine which patients with thallium redistribution are at highest risk, dipyridamole-thallium-201 images were interpreted semiquantitatively. Sixty-two consecutive patients with redistribution on preoperative dipyridamole-thallium-201 planar imaging studies were identified. Each thallium scan was then analyzed independently by 2 observers for the number of myocardial segments out of 15, the number of thallium views out of 3 and the number of coronary artery territories with redistribution. Seventeen patients (27%) had postoperative ischemic events, including unstable angina pectoris, ischemic pulmonary edema, myocardial infarction and cardiac death. Thallium predictors of ischemic operative complications included thallium redistribution greater than or equal to 4 myocardial segments (p = 0.03), greater than or equal to 2 of the 3 planar views (p = 0.005) and greater than or equal to 2 coronary territories (p = 0.007). No patient with redistribution in only 1 view had an ischemic event (0 of 15). Thus, determining the extent of redistribution by dipyridamole-thallium-201 scanning improves risk stratification before vascular surgery. Patients with greater numbers of myocardial segments and greater numbers of coronary territories showing thallium-201 redistribution are at higher risk for ischemic cardiac complications. In contrast, when the extent of thallium redistribution is limited, there is a lower risk despite the presence of redistribution

Evaluating risk management strategies in resource planning

International Nuclear Information System (INIS)

Andrews, C.J.

1995-01-01

This paper discusses the evaluation of risk management strategies as a part of integrated resource planning. Value- and scope-related uncertainties can be addressed during the process of planning, but uncertainties in the operating environment require technical analysis within planning models. Flexibility and robustness are two key classes of strategies for managing the risk posed by these uncertainties. This paper reviews standard capacity expansion planning models and shows that they are poorly equipped to compare risk management strategies. Those that acknowledge uncertainty are better at evaluating robustness than flexibility, which implies a bias against flexible options. Techniques are available to overcome this bias

Prognostic Stratification of Patients With Advanced Oral Cavity Squamous Cell Carcinoma.

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De Paz, Dante; Kao, Huang-Kai; Huang, Yenlin; Chang, Kai-Ping

2017-08-10

Prognosis of advanced oral squamous cell carcinoma remains a challenge for clinicians despite progress in its diagnosis and treatment over the past decades. In this review, we assessed clinicopathological factors and potential biomarkers along with their prognostic relevance in an attempt to develop optimal treatment strategies for these patients. In addition to several pathologic factors that have been proposed to improve prognostic stratification and treatment planning in the eighth edition of the American Joint Committee staging manual on cancer, we reviewed some other imaging and clinicopathological parameters demonstrated to be closely associated with patient prognosis, along with the biomarkers related to novel target or immune therapy. Evaluation of current literature regarding the prognostic stratification used in contemporary clinicopathological studies and progress in the development of targeted or immune therapy may help these patients benefit from tailored and personalized treatment and obtain better oncological results.

Validation of risk stratification schemes for predicting stroke and thromboembolism in patients with atrial fibrillation: nationwide cohort study.

Science.gov (United States)

Olesen, Jonas Bjerring; Lip, Gregory Y H; Hansen, Morten Lock; Hansen, Peter Riis; Tolstrup, Janne Schurmann; Lindhardsen, Jesper; Selmer, Christian; Ahlehoff, Ole; Olsen, Anne-Marie Schjerning; Gislason, Gunnar Hilmar; Torp-Pedersen, Christian

2011-01-31

To evaluate the individual risk factors composing the CHADS(2) (Congestive heart failure, Hypertension, Age ≥ 75 years, Diabetes, previous Stroke) score and the CHA(2)DS(2)-VASc (CHA(2)DS(2)-Vascular disease, Age 65-74 years, Sex category) score and to calculate the capability of the schemes to predict thromboembolism. Registry based cohort study. Nationwide data on patients admitted to hospital with atrial fibrillation. Population All patients with atrial fibrillation not treated with vitamin K antagonists in Denmark in the period 1997-2006. Stroke and thromboembolism. Of 121,280 patients with non-valvular atrial fibrillation, 73,538 (60.6%) fulfilled the study inclusion criteria. In patients at "low risk" (score = 0), the rate of thromboembolism per 100 person years was 1.67 (95% confidence interval 1.47 to 1.89) with CHADS(2) and 0.78 (0.58 to 1.04) with CHA(2)DS(2)-VASc at one year's follow-up. In patients at "intermediate risk" (score = 1), this rate was 4.75 (4.45 to 5.07) with CHADS(2) and 2.01 (1.70 to 2.36) with CHA(2)DS(2)-VASc. The rate of thromboembolism depended on the individual risk factors composing the scores, and both schemes underestimated the risk associated with previous thromboembolic events. When patients were categorised into low, intermediate, and high risk groups, C statistics at 10 years' follow-up were 0.812 (0.796 to 0.827) with CHADS(2) and 0.888 (0.875 to 0.900) with CHA(2)DS(2)-VASc. The risk associated with a specific risk stratification score depended on the risk factors composing the score. CHA(2)DS(2)-VASc performed better than CHADS(2) in predicting patients at high risk, and those categorised as low risk by CHA(2)DS(2)-VASc were truly at low risk for thromboembolism.

Risk impact of two accident management strategies

International Nuclear Information System (INIS)

Dingman, S.; Camp, A.

1992-01-01

This report probabilistic Risk Assessment is used to evaluate two accident management strategies: intentionally depressurizing the reactor coolant system of a pressurized water reactor to prevent containment-pressurization during high pressure melt ejection, and flooding the containment of a boiling water reactor to prevent or delay vessel breach. Sensitivity studies indicated that intentional depressurization would not provide a significant risk reduction at Surry. A preliminary evaluation of the containment flooding strategy indicated that it might prove beneficial for some plants, but that further strategy development would be needed to fully evaluate the strategy-

Cardiovascular Risk Stratification in Patients with Metabolic Syndrome Without Diabetes or Cardiovascular Disease: Usefulness of Metabolic Syndrome Severity Score.

Science.gov (United States)

Masson, Walter; Epstein, Teo; Huerín, Melina; Lobo, Lorenzo Martín; Molinero, Graciela; Angel, Adriana; Masson, Gerardo; Millán, Diana; De Francesca, Salvador; Vitagliano, Laura; Cafferata, Alberto; Losada, Pablo

2017-09-01

The estimated cardiovascular risk determined by the different risk scores, could be heterogeneous in patients with metabolic syndrome without diabetes or vascular disease. This risk stratification could be improved by detecting subclinical carotid atheromatosis. To estimate the cardiovascular risk measured by different scores in patients with metabolic syndrome and analyze its association with the presence of carotid plaque. Non-diabetic patients with metabolic syndrome (Adult Treatment Panel III definition) without cardiovascular disease were enrolled. The Framingham score, the Reynolds score, the new score proposed by the 2013 ACC/AHA Guidelines and the Metabolic Syndrome Severity Calculator were calculated. Prevalence of carotid plaque was determined by ultrasound examination. A Receiver Operating Characteristic analysis was performed. A total of 238 patients were enrolled. Most patients were stratified as "low risk" by Framingham score (64%) and Reynolds score (70.1%). Using the 2013 ACC/AHA score, 45.3% of the population had a risk ≥7.5%. A significant correlation was found between classic scores but the agreement (concordance) was moderate. The correlation between classical scores and the Metabolic Syndrome Severity Calculator was poor. Overall, the prevalence of carotid plaque was 28.2%. The continuous metabolic syndrome score used in our study showed a good predictive power to detect carotid plaque (area under the curve 0.752). In this population, the calculated cardiovascular risk was heterogenic. The prevalence of carotid plaque was high. The Metabolic Syndrome Severity Calculator showed a good predictive power to detect carotid plaque.

Lifetime risks for aneurysmal subarachnoid haemorrhage: multivariable risk stratification.

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Vlak, Monique H M; Rinkel, Gabriel J E; Greebe, Paut; Greving, Jacoba P; Algra, Ale

2013-06-01

The overall incidence of aneurysmal subarachnoid haemorrhage (aSAH) in western populations is around 9 per 100 000 person-years, which confers to a lifetime risk of around half per cent. Risk factors for aSAH are usually expressed as relative risks and suggest that absolute risks vary considerably according to risk factor profiles, but such estimates are lacking. We aimed to estimate incidence and lifetime risks of aSAH according to risk factor profiles. We used data from 250 patients admitted with aSAH and 574 sex-matched and age-matched controls, who were randomly retrieved from general practitioners files. We determined independent prognostic factors with multivariable logistic regression analyses and assessed discriminatory performance using the area under the receiver operating characteristic curve. Based on the prognostic model we predicted incidences and lifetime risks of aSAH for different risk factor profiles. The four strongest independent predictors for aSAH, namely current smoking (OR 6.0; 95% CI 4.1 to 8.6), a positive family history for aSAH (4.0; 95% CI 2.3 to 7.0), hypertension (2.4; 95% CI 1.5 to 3.8) and hypercholesterolaemia (0.2; 95% CI 0.1 to 0.4), were used in the final prediction model. This model had an area under the receiver operating characteristic curve of 0.73 (95% CI 0.69 to 0.76). Depending on sex, age and the four predictors, the incidence of aSAH ranged from 0.4/100 000 to 298/100 000 person-years and lifetime risk between 0.02% and 7.2%. The incidence and lifetime risk of aSAH in the general population varies widely according to risk factor profiles. Whether persons with high risks benefit from screening should be assessed in cost-effectiveness studies.

Long time durability tests of fabric inlet stratification pipes

DEFF Research Database (Denmark)

Andersen, Elsa; Furbo, Simon

2008-01-01

and that this destroys the capability of building up thermal stratification for the fabric inlet stratification pipe. The results also show that although dirt, algae etc. are deposited in the fabric pipes in the space heating tank, the capability of the fabric inlet stratifiers to build up thermal stratification...

A reconceptualization of age stratification in China.

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Yin, P; Lai, K H

1983-09-01

Using the concepts of age stratification theory--age effect, cohort effect, and subcohort differences--this paper provides a new perspective on age stratification in China. Currently, the literature suggests that the status of elderly people declined after the Communist Revolution and will further decline with modernization. We discuss the problems with this perspective and argue, instead, that the status of elderly adults did not decline for the majority of the aged during the Maoist years. Rather, the most important change in the age stratification system during the Maoist years was the change in the criterion of age stratification--from age differences to cohort and subcohort differences. Furthermore, the subcohort of elderly adults who suffered the most status decline during the Maoist years--the bourgeoisie--may actually enjoy an increase in status with the recent modernization impetus. Research suggestions from this new perspective are discussed.

Quantitative stratification of diffuse parenchymal lung diseases.

Directory of Open Access Journals (Sweden)

Sushravya Raghunath

Full Text Available Diffuse parenchymal lung diseases (DPLDs are characterized by widespread pathological changes within the pulmonary tissue that impair the elasticity and gas exchange properties of the lungs. Clinical-radiological diagnosis of these diseases remains challenging and their clinical course is characterized by variable disease progression. These challenges have hindered the introduction of robust objective biomarkers for patient-specific prediction based on specific phenotypes in clinical practice for patients with DPLD. Therefore, strategies facilitating individualized clinical management, staging and identification of specific phenotypes linked to clinical disease outcomes or therapeutic responses are urgently needed. A classification schema consistently reflecting the radiological, clinical (lung function and clinical outcomes and pathological features of a disease represents a critical need in modern pulmonary medicine. Herein, we report a quantitative stratification paradigm to identify subsets of DPLD patients with characteristic radiologic patterns in an unsupervised manner and demonstrate significant correlation of these self-organized disease groups with clinically accepted surrogate endpoints. The proposed consistent and reproducible technique could potentially transform diagnostic staging, clinical management and prognostication of DPLD patients as well as facilitate patient selection for clinical trials beyond the ability of current radiological tools. In addition, the sequential quantitative stratification of the type and extent of parenchymal process may allow standardized and objective monitoring of disease, early assessment of treatment response and mortality prediction for DPLD patients.

Quantitative Stratification of Diffuse Parenchymal Lung Diseases

Science.gov (United States)

Raghunath, Sushravya; Rajagopalan, Srinivasan; Karwoski, Ronald A.; Maldonado, Fabien; Peikert, Tobias; Moua, Teng; Ryu, Jay H.; Bartholmai, Brian J.; Robb, Richard A.

2014-01-01

Diffuse parenchymal lung diseases (DPLDs) are characterized by widespread pathological changes within the pulmonary tissue that impair the elasticity and gas exchange properties of the lungs. Clinical-radiological diagnosis of these diseases remains challenging and their clinical course is characterized by variable disease progression. These challenges have hindered the introduction of robust objective biomarkers for patient-specific prediction based on specific phenotypes in clinical practice for patients with DPLD. Therefore, strategies facilitating individualized clinical management, staging and identification of specific phenotypes linked to clinical disease outcomes or therapeutic responses are urgently needed. A classification schema consistently reflecting the radiological, clinical (lung function and clinical outcomes) and pathological features of a disease represents a critical need in modern pulmonary medicine. Herein, we report a quantitative stratification paradigm to identify subsets of DPLD patients with characteristic radiologic patterns in an unsupervised manner and demonstrate significant correlation of these self-organized disease groups with clinically accepted surrogate endpoints. The proposed consistent and reproducible technique could potentially transform diagnostic staging, clinical management and prognostication of DPLD patients as well as facilitate patient selection for clinical trials beyond the ability of current radiological tools. In addition, the sequential quantitative stratification of the type and extent of parenchymal process may allow standardized and objective monitoring of disease, early assessment of treatment response and mortality prediction for DPLD patients. PMID:24676019

Precommitted Investment Strategy versus Time-Consistent Investment Strategy for a Dual Risk Model

Directory of Open Access Journals (Sweden)

Lidong Zhang

2014-01-01

Full Text Available We are concerned with optimal investment strategy for a dual risk model. We assume that the company can invest into a risk-free asset and a risky asset. Short-selling and borrowing money are allowed. Due to lack of iterated-expectation property, the Bellman Optimization Principle does not hold. Thus we investigate the precommitted strategy and time-consistent strategy, respectively. We take three steps to derive the precommitted investment strategy. Furthermore, the time-consistent investment strategy is also obtained by solving the extended Hamilton-Jacobi-Bellman equations. We compare the precommitted strategy with time-consistent strategy and find that these different strategies have different advantages: the former can make value function maximized at the original time t=0 and the latter strategy is time-consistent for the whole time horizon. Finally, numerical analysis is presented for our results.

Various manifestations of stratification phenomenon during intravenous cholangiography

Energy Technology Data Exchange (ETDEWEB)

Tada, S; Nanjo, M; Kino, M; Sekiya, T; Harada, J; Kuroda, T; Anno, I [Jikei Univ., Tokyo (Japan). School of Medicine

1979-07-01

A classification has been made of various types of stratification phenomenon during intravenous cholangiography. The stage of gallbladder opacification in the recumbent position has been classified as (I) mottled, (II) dendritic, (III) ring-like, and (IV) homogeneous. 'Dendritic' type of stratification phenomenon has never been reported in the literature to our knowledge. At 20 min following infusion of contrast material homogeneous opacification of the gallbladder was noticed in only 14% of patients. The others fell into types I, II or III of stratification phenomenon. In contrast, 87% of the opacified gallbladders were homogeneous on the after fatty meal film. It is therefore mandatory for diagnosis that either a 24 h film or a fatty meal film be taken to avoid the stratification phenomenon.

Various manifestations of stratification phenomenon during intravenous cholangiography

International Nuclear Information System (INIS)

Tada, S.; Nanjo, M.; Kino, M.; Sekiya, T.; Harada, J.; Kuroda, T.; Anno, I.

1979-01-01

A classification has been made of various types of stratification phenomenon during intravenous cholangiography. The stage of gallbladder opacification in the recumbent position has been classified as (I) mottled, (II) dendritic, (III) ring-like, and (IV) homogeneous. 'Dendritic' type of stratification phenomenon has never been reported in the literature to our knowledge. At 20 min following infusion of contrast material homogeneous opacification of the gallbladder was noticed in only 14% of patients. The others fell into types I, II or III of stratification phenomenon. In contrast, 87% of the opacified gallbladders were homogeneous on the after fatty meal film. It is therefore mandatory for diagnosis that either a 24 h film or a fatty meal film be taken to avoid the stratification phenomenon. (author)

Nutritional strategies to reduce falls risk in older people.

Science.gov (United States)

Nash, Louise; Bergin, Nick

2018-03-23

A literature review found an association between increased falls risk and malnutrition, sarcopenia, vitamin D deficiency and dehydration. Strategies to identify, prevent and treat these conditions can help to reduce falls risk in at-risk groups such as frail, older people. Nurses can reduce falls risk in older people by raising awareness of risk factors and embedding nutritional strategies in local falls reduction strategies. ©2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

Current Management Strategy for Active Surveillance in Prostate Cancer.

Science.gov (United States)

Syed, Jamil S; Javier-Desloges, Juan; Tatzel, Stephanie; Bhagat, Ansh; Nguyen, Kevin A; Hwang, Kevin; Kim, Sarah; Sprenkle, Preston C

2017-02-01

Active surveillance has been increasingly utilized as a strategy for the management of favorable-risk, localized prostate cancer. In this review, we describe contemporary management strategies of active surveillance, with a focus on traditional stratification schemes, new prognostic tools, and patient outcomes. Patient selection, follow-up strategy, and indication for delayed intervention for active surveillance remain centered around PSA, digital rectal exam, and biopsy findings. Novel tools which include imaging, biomarkers, and genetic assays have been investigated as potential prognostic adjuncts; however, their role in active surveillance remains institutionally dependent. Although 30-50% of patients on active surveillance ultimately undergo delayed treatment, the vast majority will remain free of metastasis with a low risk of dying from prostate cancer. The optimal method for patient selection into active surveillance is unknown; however, cancer-specific mortality rates remain excellent. New prognostication tools are promising, and long-term prospective, randomized data regarding their use in active surveillance will be beneficial.

Modeling Multimodal Stratification

DEFF Research Database (Denmark)

Boeriis, Morten

2017-01-01

. The article outlines a theoretical experiment exploring how an alternative way of modeling stratification and instantiation may raise some interesting ideas on the concepts of realization dynamics, system-instance, and the different contexts of the semiotic text. This is elaborated in a discussion of how...

Does quantifying epicardial and intrathoracic fat with noncontrast computed tomography improve risk stratification beyond calcium scoring alone?

Science.gov (United States)

Forouzandeh, Farshad; Chang, Su Min; Muhyieddeen, Kamil; Zaid, Rashid R; Trevino, Alejandro R; Xu, Jiaqiong; Nabi, Faisal; Mahmarian, John J

2013-01-01

Noncontrast cardiac computed tomography allows calculation of coronary artery calcium score (CACS) and measurement of epicardial adipose tissue (EATv) and intrathoracic fat (ITFv) volumes. It is unclear whether fat volume information contributes to risk stratification. Cardiac computed tomography was performed in 760 consecutive patients with acute chest pain admitted thorough the emergency department. None had prior coronary artery disease. CACS was calculated using the Agatston method. EATv and ITFv were semiautomatically calculated. Median patient follow-up was 3.3 years. Mean patient age was 54.4±13.7 years and Framingham risk score 8.2±8.2. The 45 patients (5.9%) with major acute cardiac events (MACE) were older (64.8±13.9 versus 53.7±13.4 years), more frequently male (60% versus 40%), and had a higher median Framingham risk score (16 versus 4) and CACS (268 versus 0) versus those without events (all PEATv (154 versus 116 mL) and ITFv (330 versus 223 mL), and a higher prevalence of EATv >125 mL (67% versus 44%) and ITFv >250 mL (64% versus 42%) (all PEATv, and ITFv were all independently associated with MACE. CACS was associated with MACE after adjustment for fat volumes (PEATv and ITFv improved the risk model only in patients with CACS >400. CACS and fat volumes are independently associated with MACE in acute chest pain patients and beyond that provided by clinical information alone. Although fat volumes may add prognostic value in patients with CACS >400, CACS is most strongly correlated with outcome.

Volumetry based biomarker speed of growth: Quantifying the change of total tumor volume in whole-body magnetic resonance imaging over time improves risk stratification of smoldering multiple myeloma patients.

Science.gov (United States)

Wennmann, Markus; Kintzelé, Laurent; Piraud, Marie; Menze, Bjoern H; Hielscher, Thomas; Hofmanninger, Johannes; Wagner, Barbara; Kauczor, Hans-Ulrich; Merz, Maximilian; Hillengass, Jens; Langs, Georg; Weber, Marc-André

2018-05-18

The purpose of this study was to improve risk stratification of smoldering multiple myeloma patients, introducing new 3D-volumetry based imaging biomarkers derived from whole-body MRI. Two-hundred twenty whole-body MRIs from 63 patients with smoldering multiple myeloma were retrospectively analyzed and all focal lesions >5mm were manually segmented for volume quantification. The imaging biomarkers total tumor volume, speed of growth (development of the total tumor volume over time), number of focal lesions, development of the number of focal lesions over time and the recent imaging biomarker '>1 focal lesion' of the International Myeloma Working Group were compared, taking 2-year progression rate, sensitivity and false positive rate into account. Speed of growth, using a cutoff of 114mm 3 /month, was able to isolate a high-risk group with a 2-year progression rate of 82.5%. Additionally, it showed by far the highest sensitivity in this study and in comparison to other biomarkers in the literature, detecting 63.2% of patients who progress within 2 years. Furthermore, its false positive rate (8.7%) was much lower compared to the recent imaging biomarker '>1 focal lesion' of the International Myeloma Working Group. Therefore, speed of growth is the preferable imaging biomarker for risk stratification of smoldering multiple myeloma patients.

Proceedings of the specialists meeting on experience with thermal fatigue in LWR piping caused by mixing and stratification

International Nuclear Information System (INIS)

1998-01-01

This specialists meeting on experience with thermal fatigue in LWR piping caused by mixing and stratification, was held in June 1998 in Paris. It included five sessions. Session 1: operating experience (7 papers): Historical perspective; EDF experience with local thermohydraulic phenomena in PWRs: impacts and strategies; Thermal fatigue in safety injection lines of French PWRs: technical problems, regulatory requirements, concerns about other areas; US NRC Regulatory perspective on unanticipated thermal fatigue in LWR piping; Failure to the Residual Heat Removal system suction line pipe in Genkai unit 1 caused by thermal stratification cycling; Emergency Core Cooling System pipe crack incident at Tihange unit 1; Two leakages induced by thermal stratification at the Loviisa power plant). Session 2: thermal hydraulic phenomena (5 papers): Thermal stratification in small pipes with respect to fatigue effects and so called 'Banana effect'; Thermal stratification in the surge line of the Korean next generation reactor; Thermal stratification in horizontal pipes investigated in UPTF-TRAM and HDR facilities; Research on thermal stratification in un-isolable piping of reactor pressure boundary; Thermal mixing phenomena in piping systems: 3D numerical simulation and design considerations. Session 3: response of material and structure (5 papers): Fatigue induced by thermal stratification, Results of tests and calculations of the COUFAST model; Laboratory simulation of thermal fatigue cracking as a basis for verifying life models; Thermo-mechanical analysis methods for the conception and the follow up of components submitted to thermal stratification transients; Piping analysis methods of a PWR surge line for stratified flow; The thermal stratification effect on surge lines, The VVER estimation. Session 4: monitoring aspects (4 papers): Determination of the thermal loadings affecting the auxiliary lines of the reactor coolant system in French PWR plants; Expected and

Coronary risk assessment by point-based vs. equation-based Framingham models: significant implications for clinical care.

Science.gov (United States)

Gordon, William J; Polansky, Jesse M; Boscardin, W John; Fung, Kathy Z; Steinman, Michael A

2010-11-01

US cholesterol guidelines use original and simplified versions of the Framingham model to estimate future coronary risk and thereby classify patients into risk groups with different treatment strategies. We sought to compare risk estimates and risk group classification generated by the original, complex Framingham model and the simplified, point-based version. We assessed 2,543 subjects age 20-79 from the 2001-2006 National Health and Nutrition Examination Surveys (NHANES) for whom Adult Treatment Panel III (ATP-III) guidelines recommend formal risk stratification. For each subject, we calculated the 10-year risk of major coronary events using the original and point-based Framingham models, and then compared differences in these risk estimates and whether these differences would place subjects into different ATP-III risk groups (20% risk). Using standard procedures, all analyses were adjusted for survey weights, clustering, and stratification to make our results nationally representative. Among 39 million eligible adults, the original Framingham model categorized 71% of subjects as having "moderate" risk (20%) risk. Estimates of coronary risk by the original and point-based models often differed substantially. The point-based system classified 15% of adults (5.7 million) into different risk groups than the original model, with 10% (3.9 million) misclassified into higher risk groups and 5% (1.8 million) into lower risk groups, for a net impact of classifying 2.1 million adults into higher risk groups. These risk group misclassifications would impact guideline-recommended drug treatment strategies for 25-46% of affected subjects. Patterns of misclassifications varied significantly by gender, age, and underlying CHD risk. Compared to the original Framingham model, the point-based version misclassifies millions of Americans into risk groups for which guidelines recommend different treatment strategies.

Patients at High-Risk for Surgical Site Infection.

Science.gov (United States)

Mueck, Krislynn M; Kao, Lillian S

Surgical site infections (SSIs) are a significant healthcare quality issue, resulting in increased morbidity, disability, length of stay, resource utilization, and costs. Identification of high-risk patients may improve pre-operative counseling, inform resource utilization, and allow modifications in peri-operative management to optimize outcomes. Review of the pertinent English-language literature. High-risk surgical patients may be identified on the basis of individual risk factors or combinations of factors. In particular, statistical models and risk calculators may be useful in predicting infectious risks, both in general and for SSIs. These models differ in the number of variables; inclusion of pre-operative, intra-operative, or post-operative variables; ease of calculation; and specificity for particular procedures. Furthermore, the models differ in their accuracy in stratifying risk. Biomarkers may be a promising way to identify patients at high risk of infectious complications. Although multiple strategies exist for identifying surgical patients at high risk for SSIs, no one strategy is superior for all patients. Further efforts are necessary to determine if risk stratification in combination with risk modification can reduce SSIs in these patient populations.

Genetic Stratification in Myeloid Diseases: From Risk Assessment to Clinical Decision Support Tool

Directory of Open Access Journals (Sweden)

Yishai Ofran

2014-10-01

Full Text Available Genetic aberrations have become a dominant factor in the stratification of myeloid malignancies. Cytogenetic and a few mutation studies are the backbone of risk assessment models of myeloid malignancies which are a major consideration in clinical decisions, especially patient assignment for allogeneic stem cell transplantation. Progress in our understanding of the genetic basis of the pathogenesis of myeloid malignancies and the growing capabilities of mass sequencing may add new roles for the clinical usage of genetic data. A few recently identified mutations recognized to be associated with specific diseases or clinical scenarios may soon become part of the diagnostic criteria of such conditions. Mutational studies may also advance our capabilities for a more efficient patient selection process, assigning the most effective therapy at the best timing for each patient. The clinical utility of genetic data is anticipated to advance further with the adoption of deep sequencing and next-generation sequencing techniques. We herein suggest some future potential applications of sequential genetic data to identify pending deteriorations at time points which are the best for aggressive interventions such as allogeneic stem cell transplantation. Genetics is moving from being mostly a prognostic factor to becoming a multitasking decision support tool for hematologists. Physicians must pay attention to advances in molecular hematology as it will soon be accessible and influential for most of our patients.

A novel dual-marker expression panel for easy and accurate risk stratification of patients with gastric cancer.

Science.gov (United States)

Kanda, Mitsuro; Murotani, Kenta; Tanaka, Haruyoshi; Miwa, Takashi; Umeda, Shinichi; Tanaka, Chie; Kobayashi, Daisuke; Hayashi, Masamichi; Hattori, Norifumi; Suenaga, Masaya; Yamada, Suguru; Nakayama, Goro; Fujiwara, Michitaka; Kodera, Yasuhiro

2018-05-07

Development of specific biomarkers is necessary for individualized management of patients with gastric cancer. The aim of this study was to design a simple expression panel comprising novel molecular markers for precise risk stratification. Patients (n = 200) who underwent gastrectomy for gastric cancer were randomly assigned into learning and validation sets. Tissue mRNA expression levels of 15 candidate molecular markers were determined using quantitative PCR analysis. A dual-marker expression panel was created according to concordance index (C-index) values of overall survival for all 105 combinations of two markers in the learning set. The reproducibility and clinical significance of the dual-marker expression panel were evaluated in the validation set. The patient characteristics of the learning and validation sets were well balanced. The C-index values of combinations were significantly higher compared with those of single markers. The panel with the highest C-index (0.718) of the learning set comprised SYT8 and MAGED2, which clearly stratified patients into low-, intermediate-, and high-risk groups. The reproducibility of the panel was demonstrated in the validation set. High expression scores were significantly associated with larger tumor size, vascular invasion, lymph node metastasis, peritoneal metastasis, and advanced disease. The dual-marker expression panel provides a simple tool that clearly stratifies patients with gastric cancer into low-, intermediate-, and high risk after gastrectomy. © 2018 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Therapeutic risk management of the suicidal patient: safety planning.

Science.gov (United States)

Matarazzo, Bridget B; Homaifar, Beeta Y; Wortzel, Hal S

2014-05-01

This column is the fourth in a series describing a model for therapeutic risk management of the suicidal patient. Previous columns presented an overview of the therapeutic risk management model, provided recommendations for how to augment risk assessment using structured assessments, and discussed the importance of risk stratification in terms of both severity and temporality. This final column in the series discusses the safety planning intervention as a critical component of therapeutic risk management of suicide risk. We first present concerns related to the relatively common practice of using no-suicide contracts to manage risk. We then present the safety planning intervention as an alternative approach and provide recommendations for how to use this innovative strategy to therapeutically mitigate risk in the suicidal patient.

Role of diastolic function indices in the risk stratification of patients with mixed aortic valve disease.

Science.gov (United States)

Egbe, Alexander C; Khan, Arooj R; Boler, Amber; Said, Sameh M; Geske, Jeffrey B; Miranda, William R; Akintoye, Emmanuel; Connolly, Heidi M; Warnes, Carole A; Oh, Jae K

2018-06-01

Determine the role of diastolic function indices in pre-operative and post-operative risk stratification in patients with moderate mixed aortic valve disease (MAVD). A retrospective study was conducted of asymptomatic patients with moderate MAVD (a combination of moderate aortic stenosis and moderate aortic regurgitation) and an ejection fraction of 50% or more who were followed up at Mayo Clinic from 1 January 2004, to 31 December 2013. A pre-requisite for inclusion in the study was assessment of diastolic function involving at least three of the following indices: tissue Doppler early diastolic velocity (e'), mitral inflow early velocity (E), tricuspid regurgitation velocity, and left atrial volume index. Primary endpoints were aortic valve replacement (AVR) or cardiac death while secondary endpoints were cardiovascular adverse events (CAEs) after AVR. We defined CAEs as stroke, heart failure hospitalization, severe left ventricular dysfunction, and cardiac death. There were 214 patients (age 61 ± 8 years, men 146 [68%]) followed for 6.1 ± 2.3 years during which 162 (76%) AVRs and 11 (5%) cardiac deaths occurred. The multivariable risk factors for cardiac death or AVR were relative wall thickness (RWT) > 0.42 [hazard ratio (HR), 1.88 [95% CI, 1.28-2.59]; P = 0.001] and average E/e' >14 (HR, 1.94 [95% CI, 1.29-3.01]; P = 0.02). Freedom from CAE after AVR was significantly lower in the patients with baseline RWT >0.42 or mean E/e' >14 than the other patients: 79% (95% CI 74-83%) vs. 94% (95% CI 89-98%) at 3 years (P = 0.03). The presence of RWT >0.42 or E/e' >14 identifies a high-risk patient subset whose risk for cardiovascular morbidities persists even after AVR.

Molecular markers of carcinogenesis for risk stratification of individuals with colorectal polyps: a case-control study.

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Gupta, Samir; Sun, Han; Yi, Sang; Storm, Joy; Xiao, Guanghua; Balasubramanian, Bijal A; Zhang, Song; Ashfaq, Raheela; Rockey, Don C

2014-10-01

Risk stratification using number, size, and histology of colorectal adenomas is currently suboptimal for identifying patients at increased risk for future colorectal cancer. We hypothesized that molecular markers of carcinogenesis in adenomas, measured via immunohistochemistry, may help identify high-risk patients. To test this hypothesis, we conducted a retrospective, 1:1 matched case-control study (n = 216; 46% female) in which cases were patients with colorectal cancer and synchronous adenoma and controls were patients with adenoma but no colorectal cancer at baseline or within 5 years of follow-up. In phase I of analyses, we compared expression of molecular markers of carcinogenesis in case and control adenomas, blind to case status. In phase II of analyses, patients were randomly divided into independent training and validation groups to develop a model for predicting case status. We found that seven markers [p53, p21, Cox-2, β-catenin (BCAT), DNA-dependent protein kinase (DNApkcs), survivin, and O6-methylguanine-DNA methyltransferase (MGMT)] were significantly associated with case status on unadjusted analyses, as well as analyses adjusted for age and advanced adenoma status (P marker component). When applied to the validation set, a predictive model using these seven markers showed substantial accuracy for identifying cases [area under the receiver operation characteristic curve (AUC), 0.83; 95% confidence interval (CI), 0.74-0.92]. A parsimonious model using three markers performed similarly to the seven-marker model (AUC, 0.84). In summary, we found that molecular markers of carcinogenesis distinguished adenomas from patients with and without colorectal cancer. Furthermore, we speculate that prospective studies using molecular markers to identify individuals with polyps at risk for future neoplasia are warranted. ©2014 American Association for Cancer Research.

Optimized endogenous post-stratification in forest inventories

Science.gov (United States)

Paul L. Patterson

2012-01-01

An example of endogenous post-stratification is the use of remote sensing data with a sample of ground data to build a logistic regression model to predict the probability that a plot is forested and using the predicted probabilities to form categories for post-stratification. An optimized endogenous post-stratified estimator of the proportion of forest has been...

Risk evaluation of accident management strategies

International Nuclear Information System (INIS)

Dingman, S.; Camp, A.

1992-01-01

The use of Probabilistic Risk Assessment (PRA) methods to evaluate accident management strategies in nuclear power plants discussed in this paper. The PRA framework allows an integrated evaluation to be performed to give the full implications of a particular strategy. The methodology is demonstrated for a particular accident management strategy, intentional depressurization of the reactor coolant system to avoid containment pressurization during the ejection of molten debris at vessel breach

Studies of thermal stratification in water pool

International Nuclear Information System (INIS)

Verma, P.K.; Chandraker, D.K.; Nayak, A.K.; Vijayan, P.K.

2015-01-01

Large water pools are used as a heat sink for various cooling systems used in industry. In context of advance nuclear reactors like AHWR, it is used as ultimate heat sink for passive systems for decay heat removal and containment cooling. This system incorporates heat exchangers submerged in the large water pool. However, heat transfer by natural convection in pool poses a problem of thermal stratification. Due to thermal stratification hot layers of water accumulate over the relatively cold one. The heat transfer performance of heat exchanger gets deteriorated as a hot fluid envelops it. In the nuclear reactors, the walls of the pool are made of concrete and it may subject to high temperature due to thermal stratification which is not desirable. In this paper, a concept of employing shrouds around the heat source is studied. These shrouds provide a bulk flow in the water pool, thereby facilitating mixing of hot and cold fluid, which eliminate stratification. The concept has been applied to the a scaled model of Gravity Driven Water Pool (GDWP) of AHWR in which Isolation Condensers (IC) tubes are submerged for decay heat removal of AHWR using ICS and thermal stratification phenomenon was predicted with and without shrouds. To demonstrate the adequacy of the effectiveness of shroud arrangement and to validate the simulation methodology of RELAP5/Mod3.2, experiments has been conducted on a scaled model of the pool with and without shroud. (author)

Social Stratification in the Workplace in Nigeria

Directory of Open Access Journals (Sweden)

Emmanuel Obukovwo Okaka

2017-06-01

Full Text Available Nigerian society in pre-colonial era was stratified according to royalty, military might, wealth and religious hierarchy as the case may be. But with the advent of paid employment, the social stratification shifted from a traditional format to one outlined with Western societies. The argument put forward is that social class in modern time has only been re-defined, thereby giving Nigeria a unique social stratification with a strong traditional/religious influence. This paper examined the social stratification in Nigeria with the backdrop of the introduction of paid employment and the impact of this unique social classification in the workplace. In examining social stratification in the workplace, four hundred and eighty respondents were interviewed using structured questionnaire in a onetime survey. Data collected indicates that seventy-nine percent of the surveyed group preferred to be classified with traditional or religious strata than academic class. Indicating that, royalty takes the front seat in the stratification of the Nigerian society even in the work place. This scenario may account for the emphasis Nigerians place on traditional and religious titles over academic titles in almost all sphere of life including the workplace. This calls for the strengthening of the traditional and religious institutions so that they can assist to impart core social values on members of the society, while giving proper honour to those who are accomplished professionals in their various fields of endeavours.

Revealing the timing of ocean stratification using remotely sensed ocean fronts

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Miller, Peter I.; Loveday, Benjamin R.

2017-10-01

Stratification is of critical importance to the circulation, mixing and productivity of the ocean, and is expected to be modified by climate change. Stratification is also understood to affect the surface aggregation of pelagic fish and hence the foraging behaviour and distribution of their predators such as seabirds and cetaceans. Hence it would be prudent to monitor the stratification of the global ocean, though this is currently only possible using in situ sampling, profiling buoys or underwater autonomous vehicles. Earth observation (EO) sensors cannot directly detect stratification, but can observe surface features related to the presence of stratification, for example shelf-sea fronts that separate tidally-mixed water from seasonally stratified water. This paper describes a novel algorithm that accumulates evidence for stratification from a sequence of oceanic front maps, and discusses preliminary results in comparison with in situ data and simulations from 3D hydrodynamic models. In certain regions, this method can reveal the timing of the seasonal onset and breakdown of stratification.

Role of late gadolinium enhancement cardiovascular magnetic resonance in the risk stratification of hypertrophic cardiomyopathy.

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Ismail, Tevfik F; Jabbour, Andrew; Gulati, Ankur; Mallorie, Amy; Raza, Sadaf; Cowling, Thomas E; Das, Bibek; Khwaja, Jahanzaib; Alpendurada, Francisco D; Wage, Ricardo; Roughton, Michael; McKenna, William J; Moon, James C; Varnava, Amanda; Shakespeare, Carl; Cowie, Martin R; Cook, Stuart A; Elliott, Perry; O'Hanlon, Rory; Pennell, Dudley J; Prasad, Sanjay K

2014-12-01

Myocardial fibrosis identified by late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) in patients with hypertrophic cardiomyopathy (HCM) is associated with adverse cardiovascular events, but its value as an independent risk factor for sudden cardiac death (SCD) is unknown. We investigated the role of LGE-CMR in the risk stratification of HCM. We conducted a prospective cohort study in a tertiary referral centre. Consecutive patients with HCM (n=711, median age 56.3 years, IQR 46.7-66.6; 70.0% male) underwent LGE-CMR and were followed for a median 3.5 years. The primary end point was SCD or aborted SCD. Overall, 471 patients (66.2%) had myocardial fibrosis (median 5.9% of left ventricular mass, IQR: 2.2-13.3). Twenty-two (3.1%) reached the primary end point. The extent but not the presence of fibrosis was a significant univariable predictor of the primary end point (HR per 5% LGE: 1.24, 95% CI 1.06 to 1.45; p=0.007 and HR for LGE: 2.69, 95% CI 0.91 to 7.97; p=0.073, respectively). However, on multivariable analysis, only LV-EF remained statistically significant (HR: 0.92, 95% CI 0.89 to 0.95; p<0.001). For the secondary outcome of cardiovascular mortality/aborted SCD, the presence and the amount of fibrosis were significant predictors on univariable but not multivariable analysis after adjusting for LV-EF and non-sustained ventricular tachycardia. The amount of myocardial fibrosis was a strong univariable predictor of SCD risk. However, this effect was not maintained after adjusting for LV-EF. Further work is required to elucidate the interrelationship between fibrosis and traditional predictors of outcome in HCM. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Simple risk stratification at admission to identify patients with reduced mortality from primary angioplasty

DEFF Research Database (Denmark)

Thune, Jens Jakob; Hoefsten, Dan Eik; Lindholm, Matias Greve

2005-01-01

BACKGROUND: Randomized trials comparing fibrinolysis with primary angioplasty for acute ST-elevation myocardial infarction have demonstrated a beneficial effect of primary angioplasty on the combined end point of death, reinfarction, and disabling stroke but not on all-cause death. Identifying...... a patient group with reduced mortality from an invasive strategy would be important for early triage. The Thrombolysis in Myocardial Infarction (TIMI) risk score is a simple validated integer score that makes it possible to identify high-risk patients on admission to hospital. We hypothesized that a high...... as high risk. There was a significant interaction between risk status and effect of primary angioplasty (P=0.008). In the low-risk group, there was no difference in mortality (primary angioplasty, 8.0%; fibrinolysis, 5.6%; P=0.11); in the high-risk group, there was a significant reduction in mortality...

Efficacy of risk stratification in tailoring immunosuppression regimens in kidney transplant patients at the national kidney and transplant institute.

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Ledesma-Gumba, M A; Danguilan, R A; Casasola, C C; Ona, E T

2008-09-01

To evaluate the efficacy of tailored immunosuppressive regimens prescribed according to a risk stratification scoring system based on the number of HLA mismatches, donor source, panel-reactive antibodies (PRA), and repeat transplant. Patients in a retrospective cohort of 329 kidney transplantations performed from October 2004 to December 2005 were assigned scores of 0, 2, 4, or 6 with higher scores for > or =1 HLA mismatches, PRA > 10%, repeat transplant, and unrelated or deceased donor. Added scores of or = 6 denoted high risk including a CNI-based regimen with an interleukin-2 receptor antibody. The efficacy analysis compared the incidences of biopsy-proven acute rejection episodes (BPAR) at 1 year. Only 227 (69%) of 329 patients had a complete data set and 84 were excluded because they did not follow the prescribed protocol, yielding 113 low- and 30 high-risk patients in the final population. Low-risk patients had a mean PRA of 5.4%, living related donors in 68%, and primary transplants. High-risk patients had a mean PRA of 18.8% (range = 10%-97%), living nonrelated donors in 84%, four deceased donors, and four repeat transplants. The overall 1-year incidence of BPAR was 5.7%. No significant difference (P = .081) was observed in 1-year BPAR between the low- (4.5%) and high-risk (9.8%) groups. Likewise, no significant difference in the 1-year mean serum creatinine was observed according to the CNI. The mean creatinine was 1.12 for cyclosporine and 1.38 for tacrolimus treatment (P = .06) in the low-risk group and 1.08 for cyclosporine and 1.2 for tacrolimus (P = .61) in the high-risk cohort. There was no significant difference in acute rejection rates between the immunologically low- or high-risk patients using tailored immunosuppression, which was effective to minimize its occurrence with good renal function at 1 year.

Management and policy: political strategies and instruments of the risk types

International Nuclear Information System (INIS)

Renn, O.; Klinke, A.

1998-01-01

The main objective of the risk classification is to gain an effective and feasible policy tool for the evaluation and the management or risks. The characterisation provides a platform for designing specific political strategies and measures for each risk type. The strategies pursue the goal to transform unacceptable into acceptable risks, i.e. the risks should not be reduced to zero, but they should be reduced to a level that routine risk management becomes sufficient to ensure safety and integrity. All strategies and respective measures are arranged according to priorities. In the normal case more than one strategy and more than one measure are naturally appropriate and necessary. If resources are limited, strategies and measures should be taken in line with the priority list. The following part lists the prior strategies and the prior measures recommended for each risk type. (authors)

Investigations on stratification devices for hot water stores

DEFF Research Database (Denmark)

Andersen, Elsa; Furbo, Simon; Hampel, Matthias

2008-01-01

The significance of the thermal stratification for the energy efficiency of small solar-thermal hot water heat stores is pointed out. Exemplary the thermal stratification build-up with devices already marketed as well as with devices still in development has been investigated experimentally...

Role of anti-domain 1-β2 glycoprotein I antibodies in the diagnosis and risk stratification of antiphospholipid syndrome.

Science.gov (United States)

De Craemer, A-S; Musial, J; Devreese, K M J

2016-09-01

Essentials Antibodies to domain 1 of β2 glycoprotein I (aD1) are a subset of antiphospholipid antibodies. We evaluated the added diagnostic value of an automated aD1 assay in antiphospholipid syndrome. AD1 IgG correctly classifies patients at risk for thrombosis. Agreement between aD1 and aβ2GPI IgG is high, limiting the added value of aD1 in our setting. Click to hear Professor de Groot's perspective on new mechanistic understanding in antiphospholipid syndrome Background Laboratory diagnosis of antiphospholipid syndrome (APS) includes lupus anticoagulant (LAC), anticardiolipin (aCL) or anti-β2 glycoprotein I (aβ2 GPI) antibodies. Antibodies targeting domain 1 of β2 GPI (aD1) constitute a pathogenic subset of autoantibodies. Objectives In this cohort study, we determined the clinical performance characteristics, additional diagnostic value and the contribution to APS risk stratification of an automated aD1 assay. Patients/Methods LAC, aCL, aβ2 GPI and aD1 IgG were measured in 101 APS patients, 123 patients with autoimmune disorders, 82 diseased controls and 120 healthy controls. aD1 antibodies were detected by QUANTA Flash(®) Beta2GPI-Domain 1 chemiluminescence immunoassay. Results With a cut-off value of 20.0 CU, the aD1 IgG assay identifies APS patients in a clinically affected patient cohort with a sensitivity of 53.5% and specificity of 98.8%. It implied a high odds ratio (OR) for clinical events (OR, 17.0; 95% confidence interval [CI], 7.1-40.5). aD1 IgG did not add diagnostic value to the formal aPL panel because aβ2 GPI IgG was nearly as specific but more sensitive for APS (sensitivity 56.4%) with a higher OR for clinical events (36.2; 95% CI, 11.1-117.9). High aD1 titers identify triple-positive patients and patients with thrombosis in a β2 GPI-dependent LAC-positive population. Agreement between aD1 IgG and aβ2 GPI IgG was high (positive and negative agreement 91.7% and 98.4%, respectively). Conclusion Detection of aD1 IgG correctly classifies

Prehypertension: risk stratification and management considerations.

Science.gov (United States)

Egan, Brent M; Julius, Stevo

2008-10-01

Approximately 37% of US adults are prehypertensive; about 31 million have blood pressures in the range of 130-139/85-89 mm Hg. These stage 2 prehypertensives have threefold greater risk for developing hypertension and twofold higher risk for cardiovascular events than normotensives. Lifestyle changes only are recommended for most prehypertensives, but evidence for community-wide effectiveness is limited. Projected numbers needed to treat to prevent a cardiovascular event are similar for stage 2 prehypertension and stage 1 hypertension when both groups are matched for concomitant risk factors. However, no clinical trials document that pharmacotherapy reduces cardiovascular events in stage 2 prehypertension. The Trial of Preventing Hypertension demonstrated that angiotensin receptor blockade safely lowers blood pressure and prevents or delays progression to hypertension in stage 2 prehypertensives. We believe it is reasonable for clinicians to identify stage 2 prehypertensives at high absolute risk for progression to hypertension and cardiovascular events, and to treat them with a renin-angiotensin system blocker when lifestyle changes alone are ineffective.

Developing a risk stratification tool for audit of outcome after surgery for head and neck squamous cell carcinoma.

Science.gov (United States)

Tighe, David F; Thomas, Alan J; Sassoon, Isabel; Kinsman, Robin; McGurk, Mark

2017-07-01

Patients treated surgically for head and neck squamous cell carcinoma (HNSCC) represent a heterogeneous group. Adjusting for patient case mix and complexity of surgery is essential if reporting outcomes represent surgical performance and quality of care. A case note audit totaling 1075 patients receiving 1218 operations done for HNSCC in 4 cancer networks was completed. Logistic regression, decision tree analysis, an artificial neural network, and Naïve Bayes Classifier were used to adjust for patient case-mix using pertinent preoperative variables. Thirty-day complication rates varied widely (34%-51%; P risk stratification. The artificial neural network demonstrated the best predictive performance (area under the curve [AUC] 0.85). Early postoperative complications are a measurable outcome that can be used to benchmark surgical performance and quality of care. Surgical outcome reporting in national clinical audits should be taking account of the patient case mix. © 2017 Wiley Periodicals, Inc.

Water-Column Stratification Observed along an AUV-Tracked Isotherm

Science.gov (United States)

Zhang, Y.; Messié, M.; Ryan, J. P.; Kieft, B.; Stanway, M. J.; Hobson, B.; O'Reilly, T. C.; Raanan, B. Y.; Smith, J. M.; Chavez, F.

2016-02-01

Studies of marine physical, chemical and microbiological processes benefit from observing in a Lagrangian frame of reference, i.e. drifting with ambient water. Because these processes can be organized relative to specific density or temperature ranges, maintaining observing platforms within targeted environmental ranges is an important observing strategy. We have developed a novel method to enable a Tethys-class long-range autonomous underwater vehicle (AUV) (which has a propeller and a buoyancy engine) to track a target isotherm in buoyancy-controlled drift mode. In this mode, the vehicle shuts off its propeller and autonomously detects the isotherm and stays with it by actively controlling the vehicle's buoyancy. In the June 2015 CANON (Controlled, Agile, and Novel Observing Network) Experiment in Monterey Bay, California, AUV Makai tracked a target isotherm for 13 hours to study the coastal upwelling system. The tracked isotherm started from 33 m depth, shoaled to 10 m, and then deepened to 29 m. The thickness of the tracked isotherm layer (within 0.3°C error from the target temperature) increased over this duration, reflecting weakened stratification around the isotherm. During Makai's isotherm tracking, another long-range AUV, Daphne, acoustically tracked Makai on a circular yo-yo trajectory, measuring water-column profiles in Makai's vicinity. A wave glider also acoustically tracked Makai, providing sea surface measurements on the track. The presented method is a new approach for studying water-column stratification, but requires careful analysis of the temporal and spatial variations mingled in the vehicles' measurements. We will present a synthesis of the water column's stratification in relation to the upwelling conditions, based on the in situ measurements by the mobile platforms, as well as remote sensing and mooring data.

Non-Rhabdomyosarcoma Soft Tissue Sarcomas in Children: A Surveillance, Epidemiology, and End Results Analysis Validating COG Risk Stratifications

Energy Technology Data Exchange (ETDEWEB)

Waxweiler, Timothy V., E-mail: timothy.waxweiler@ucdenver.edu [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States); Rusthoven, Chad G. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States); Proper, Michelle S. [Department of Radiation Oncology, Billings Clinic, Billings, Montana (United States); Cost, Carrye R. [Division of Hematology and Oncology, Department of Pediatrics, University of Colorado Denver School of Medicine, Aurora, Colorado (United States); Cost, Nicholas G. [Division of Urology, Department of Surgery, University of Colorado Denver School of Medicine, Aurora, Colorado (United States); Donaldson, Nathan [Department of Orthopedics, University of Colorado Denver School of Medicine, Aurora, Colorado (United States); Garrington, Timothy; Greffe, Brian S. [Division of Hematology and Oncology, Department of Pediatrics, University of Colorado Denver School of Medicine, Aurora, Colorado (United States); Heare, Travis [Department of Orthopedics, University of Colorado Denver School of Medicine, Aurora, Colorado (United States); Macy, Margaret E. [Division of Hematology and Oncology, Department of Pediatrics, University of Colorado Denver School of Medicine, Aurora, Colorado (United States); Liu, Arthur K. [Department of Radiation Oncology, University of Colorado School of Medicine, Aurora, Colorado (United States)

2015-06-01

Purpose: Non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) are a heterogeneous group of sarcomas that encompass over 35 histologies. With an incidence of ∼500 cases per year in the United States in those <20 years of age, NRSTS are rare and therefore difficult to study in pediatric populations. We used the large Surveillance, Epidemiology, and End Results (SEER) database to validate the prognostic ability of the Children's Oncology Group (COG) risk classification system and to define patient, tumor, and treatment characteristics. Methods and Materials: From SEER data from 1988 to 2007, we identified patients ≤18 years of age with NRSTS. Data for age, sex, year of diagnosis, race, registry, histology, grade, primary size, primary site, stage, radiation therapy, and survival outcomes were analyzed. Patients with nonmetastatic grossly resected low-grade tumors of any size or high-grade tumors ≤5 cm were considered low risk. Cases of nonmetastatic tumors that were high grade, >5 cm, or unresectable were considered intermediate risk. Patients with nodal or distant metastases were considered high risk. Results: A total of 941 patients met the review criteria. On univariate analysis, black race, malignant peripheral nerve sheath (MPNST) histology, tumors >5 cm, nonextremity primary, lymph node involvement, radiation therapy, and higher risk group were associated with significantly worse overall survival (OS) and cancer-specific survival (CSS). On multivariate analysis, MPNST histology, chemotherapy-resistant histology, and higher risk group were significantly poor prognostic factors for OS and CSS. Compared to low-risk patients, intermediate patients showed poorer OS (hazard ratio [HR]: 6.08, 95% confidence interval [CI]: 3.53-10.47, P<.001) and CSS (HR: 6.27; 95% CI: 3.44-11.43, P<.001), and high-risk patients had the worst OS (HR: 13.35, 95% CI: 8.18-21.76, P<.001) and CSS (HR: 14.65, 95% CI: 8.49-25.28, P<.001). Conclusions: The current COG risk group

A new stratification of mourning dove call-count routes

Science.gov (United States)

Blankenship, L.H.; Humphrey, A.B.; MacDonald, D.

1971-01-01

The mourning dove (Zenaidura macroura) call-count survey is a nationwide audio-census of breeding mourning doves. Recent analyses of the call-count routes have utilized a stratification based upon physiographic regions of the United States. An analysis of 5 years of call-count data, based upon stratification using potential natural vegetation, has demonstrated that this uew stratification results in strata with greater homogeneity than the physiographic strata, provides lower error variance, and hence generates greatet precision in the analysis without an increase in call-count routes. Error variance was reduced approximately 30 percent for the contiguous United States. This indicates that future analysis based upon the new stratification will result in an increased ability to detect significant year-to-year changes.

Validation of a risk stratification tool for fall-related injury in a state-wide cohort.

Science.gov (United States)

McCoy, Thomas H; Castro, Victor M; Cagan, Andrew; Roberson, Ashlee M; Perlis, Roy H

2017-02-06

A major preventable contributor to healthcare costs among older individuals is fall-related injury. We sought to validate a tool to stratify such risk based on readily available clinical data, including projected medication adverse effects, using state-wide medical claims data. Sociodemographic and clinical features were drawn from health claims paid in the state of Massachusetts for individuals aged 35-65 with a hospital admission for a period spanning January-December 2012. Previously developed logistic regression models of hospital readmission for fall-related injury were refit in a testing set including a randomly selected 70% of individuals, and examined in a training set comprised of the remaining 30%. Medications at admission were summarised based on reported adverse effect frequencies in published medication labelling. The Massachusetts health system. A total of 68 764 hospitalised individuals aged 35-65 years. Hospital readmission for fall-related injury defined by claims code. A total of 2052 individuals (3.0%) were hospitalised for fall-related injury within 90 days of discharge, and 3391 (4.9%) within 180 days. After recalibrating the model in a training data set comprised of 48 136 individuals (70%), model discrimination in the remaining 30% test set yielded an area under the receiver operating characteristic curve (AUC) of 0.74 (95% CI 0.72 to 0.76). AUCs were similar across age decades (0.71 to 0.78) and sex (0.72 male, 0.76 female), and across most common diagnostic categories other than psychiatry. For individuals in the highest risk quartile, 11.4% experienced fall within 180 days versus 1.2% in the lowest risk quartile; 57.6% of falls occurred in the highest risk quartile. This analysis of state-wide claims data demonstrates the feasibility of predicting fall-related injury requiring hospitalisation using readily available sociodemographic and clinical details. This translatable approach to stratification allows for identification of

The role stratification on Indian ocean mixing under global warming

Science.gov (United States)

Praveen, V.; Valsala, V.; Ravindran, A. M.

2017-12-01

The impact of changes in Indian ocean stratification on mixing under global warming is examined. Previous studies on global warming and associated weakening of winds reported to increase the stratification of the world ocean leading to a reduction in mixing, increased acidity, reduced oxygen and there by a reduction in productivity. However this processes is not uniform and are also modulated by changes in wind pattern of the future. Our study evaluate the role of stratification and surface fluxes on mixing focusing northern Indian ocean. A dynamical downscaling study using Regional ocean Modelling system (ROMS) forced with stratification and surface fluxes from selected CMIP5 models are presented. Results from an extensive set of historical and Representative Concentration Pathways 8.5 (rcp8.5) scenario simulations are used to quantify the distinctive role of stratification on mixing.

Patient characteristics and stratification in medical treatment studies for metastatic colorectal cancer: a proposal for standardization of patient characteristic reporting and stratification.

Science.gov (United States)

Sorbye, H; Köhne, C-H; Sargent, D J; Glimelius, B

2007-10-01

Prognostic factors have the potential to determine the survival of patients to a greater extent than current antineoplastic agents. Despite this knowledge, there is no consensus on, first, what patient characteristics to report and, second, what stratification factors to use in metastatic colorectal cancer trials. Seven leading oncology and medical journals were reviewed for phase II and III publications reporting on medical treatment of metastatic colorectal cancer patients during 2001-2005. One hundred and forty-three studies with 21 214 patients were identified. The reporting of patient characteristics and use of stratification was noted. Age, gender, performance status, metastases location, sites and adjuvant chemotherapy were often reported (99-63%). Laboratory values as alkaline phosphatase, lactate dehydrogenase and white blood cell count, repeatedly found to be of prognostic relevance, were rarely reported (5-9%). Stratification was used in all phase III trials; however, only study centre was used with any consistency. There is considerable inconsistency in the reporting of patient characteristics and use of stratification factors in metastatic colorectal cancer trials. We propose a standardization of patient characteristics reporting and stratification factors. A common set of characteristics and strata will aid in trial reporting, interpretation and future meta-analyses.

Risk stratification of patients with combined acute pulmonary embolism and pulmonary hypertension using dynamic and regular pulmonary perfusion imaging

International Nuclear Information System (INIS)

Wang Xuemei; Wang Jing; Li Guohua; Wang Xiangcheng; Zhang Kaixiu; Liu Caiping

2010-01-01

Objective: To stratify the risks of patients with acute pulmonary embolism (APE) and pulmonary hypertension (PH) by dynamic pulmonary perfusion imaging (DPPI) and pulmonary perfusion imaging (PPI). Methods: From October 2007 to February 2009, 20 healthy volunteers (12 males, 8 females; mean age =48.47±13.47 years) and 31 APE patients (21 males, 10 females; mean age =47.68±18.06 years; from October 2007 to July 2009) were included in the study. DPPI and PPI were performed in all subjects. Percentage of perfusion defect scores (PPDs%) were calculated by semi-quantitative analysis of PPI. Risk levels were defined according to PPDs% calculated from PPI: normal (PPDs% =0); very low risk (0 60%). Lung equilibrium time (LET) was calculated on region of interest (ROI) drawn over DPPI. Clinical risk was scored by Aujesky method.The t-test, ANOVA and correlation analysis were used with SPSS 13.0 software. Results: (1) LET in healthy volunteers and APE patients was (12.18±3.28) and (32.90±14.29) s respectively (t = 6.81, P<0.01). (2) The correlation coefficient, coefficient of determination between LET and PPDs% in APE patients were 0.93 and 0.87, respectively. The correlation coefficient between LET and clinical risk score was 0.86. (3) The mean LET of APE patients in very low risk (n =5), low risk (n = 12), moderate risk (n=9), high risk (n=4) and very high risk groups (n=1) were (19.59 ±0.04), (25.03±0.08), (36.07±0.10), (57.15±0.06) and (70±0.00) s, respectively. There was significant difference among APE patients with different risk levels (F =16.78, P<0.01). Conclusions: (1) DPPI was a reliable, convenient and non-invasive method for the evaluation of PH in APE. (2) Combined LET of DPPI and PPDs% of PPI was valuable for risk stratification and prognosis estimation in APE patients. (authors)

Vertical Stratification of Soil Phosphorus as a Concern for Dissolved Phosphorus Runoff in the Lake Erie Basin.

Science.gov (United States)

Baker, David B; Johnson, Laura T; Confesor, Remegio B; Crumrine, John P

2017-11-01

During the re-eutrophication of Lake Erie, dissolved reactive phosphorus (DRP) loading and concentrations to the lake have nearly doubled, while particulate phosphorus (PP) has remained relatively constant. One potential cause of increased DRP concentrations is P stratification, or the buildup of soil-test P (STP) in the upper soil layer (soil samples (0-5 or 0-2.5 cm) alongside their normal agronomic samples (0-20 cm) ( = 1758 fields). The mean STP level in the upper 2.5 cm was 55% higher than the mean of agronomic samples used for fertilizer recommendations. The amounts of stratification were highly variable and did not correlate with agronomic STPs (Spearman's = 0.039, = 0.178). Agronomic STP in 70% of the fields was within the buildup or maintenance ranges for corn ( L.) and soybeans [ (L.) Merr.] (0-46 mg kg Mehlich-3 P). The cumulative risks for DRP runoff from the large number of fields in the buildup and maintenance ranges exceeded the risks from fields above those ranges. Reducing stratification by a one-time soil inversion has the potential for larger and quicker reductions in DRP runoff risk than practices related to drawing down agronomic STP levels. Periodic soil inversion and mixing, targeted by stratified STP data, should be considered a viable practice to reduce DRP loading to Lake Erie. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

The impact of social stratification on cultural consumption

Directory of Open Access Journals (Sweden)

Tomić Marta

2016-01-01

Full Text Available This paper examines theoretical perspectives, research approaches and research results about the relationship between social stratification and cultural consumption. Paper presents main representatives of three sociological discourses: those who believe that class divisions still exist and that thay had an influence on the social inequalities, especially in the domain of cultural consumption and tastes; authors and researchers who emphasize the impact of social stratification on the formation of cultural stratification, and the third group which consists of those who are advocates of cultural consumptions theories and individualization and cultural tastes which means that membership of a particular social class are not by any cultural influences.

Development of a modified prognostic index for patients with aggressive adult T-cell leukemia-lymphoma aged 70 years or younger: possible risk-adapted management strategies including allogeneic transplantation.

Science.gov (United States)

Fuji, Shigeo; Yamaguchi, Takuhiro; Inoue, Yoshitaka; Utsunomiya, Atae; Moriuchi, Yukiyoshi; Uchimaru, Kaoru; Owatari, Satsuki; Miyagi, Takashi; Taguchi, Jun; Choi, Ilseung; Otsuka, Eiichi; Nakachi, Sawako; Yamamoto, Hisashi; Kurosawa, Saiko; Tobinai, Kensei; Fukuda, Takahiro

2017-07-01

Adult T-cell leukemia-lymphoma is a distinct type of peripheral T-cell lymphoma caused by human T-cell lymphotropic virus type I. Although allogeneic stem cell transplantation after chemotherapy is a recommended treatment option for patients with aggressive adult T-cell leukemia-lymphoma, there is no consensus about indications for allogeneic stem cell transplantation because there is no established risk stratification system for transplant eligible patients. We conducted a nationwide survey of patients with aggressive adult T-cell leukemia-lymphoma in order to construct a new, large database that includes 1,792 patients aged 70 years or younger with aggressive adult T-cell leukemia-lymphoma who were diagnosed between 2000 and 2013 and received intensive first-line chemotherapy. We randomly divided patients into two groups (training and validation sets). Acute type, poor performance status, high soluble interleukin-2 receptor levels (> 5,000 U/mL), high adjusted calcium levels (≥ 12 mg/dL), and high C-reactive protein levels (≥ 2.5 mg/dL) were independent adverse prognostic factors used in the training set. We used these five variables to divide patients into three risk groups. In the validation set, median overall survival for the low-, intermediate-, and high-risk groups was 626 days, 322 days, and 197 days, respectively. In the intermediate- and high-risk groups, transplanted recipients had significantly better overall survival than non-transplanted patients. We developed a promising new risk stratification system to identify patients aged 70 years or younger with aggressive adult T-cell leukemia-lymphoma who may benefit from upfront allogeneic stem cell transplantation. Prospective studies are warranted to confirm the benefit of this treatment strategy. Copyright© 2017 Ferrata Storti Foundation.

Experimental studies on the thermal stratification and its influence on BLEVEs

Energy Technology Data Exchange (ETDEWEB)

Lin, Wensheng; Gong, Yanwu; Gao, Ting; Gu, Anzhong; Lu, Xuesheng [Institute of Refrigeration and Cryogenics, Shanghai Jiao Tong University, Shanghai 200240 (China)

2010-10-15

The thermal stratification of Liquefied Petroleum Gas (LPG) and its effect on the occurrence of the boiling liquid expanding vapor explosion (BLEVE) have been investigated experimentally. Stratifications in liquid and vapor occur when the LPG tank is heated. The degree of the liquid stratification {beta} increases with an increasing heat flux and decreasing filling ratio. The effect of stratification on the BLEVE has been examined with depressurization tests of LPG. The results show that the pressure recovery for the stratified LPG ({beta} = 1.4) upon sudden depressurization is much lower than that for the isothermal LPG ({beta} = 1). It can be concluded that the liquid stratification decreases the liquid energy and the occurrence of the BLEVE. (author)

Export strategy risks and governance in the clothing industry

Directory of Open Access Journals (Sweden)

Arthur Mapanga

2016-08-01

Full Text Available This paper investigates the export strategy implementation risks in Zimbabwe’s clothing sector with a view to build a framework for improving strategy implementation and governance. The government of Zimbabwe has formulated a five year export strategic blue-print to resuscitate the clothing value chain. However, to date, no visible movement towards implementing the export strategy has materialised. The sector is on the brink of collapse putting the welfare and livelihood of over two million people dependent on the sector at risk. A desk research and key informant interviews were conducted to understand the barriers causing inertia in the implementation of the export strategy. Cotton farmers’ unions’ representatives, the cotton ginners association members, the spinning industry members and garment manufacturers representatives, clothing retailers’ representatives, workers’ unions’ members and government officials were important sources of information towards the discovery of the risks. From the research, six of the strategy implementation risks were linked to human elements. Leadership, consensus and commitment deficiencies militated against the implementation of the export strategy in the clothing value chain. There is also a lack of trust among the value chain actors leading to the dislocation of efforts to resuscitate the sector

Cancer Stratification by Molecular Imaging

Directory of Open Access Journals (Sweden)

Justus Weber

2015-03-01

Full Text Available The lack of specificity of traditional cytotoxic drugs has triggered the development of anticancer agents that selectively address specific molecular targets. An intrinsic property of these specialized drugs is their limited applicability for specific patient subgroups. Consequently, the generation of information about tumor characteristics is the key to exploit the potential of these drugs. Currently, cancer stratification relies on three approaches: Gene expression analysis and cancer proteomics, immunohistochemistry and molecular imaging. In order to enable the precise localization of functionally expressed targets, molecular imaging combines highly selective biomarkers and intense signal sources. Thus, cancer stratification and localization are performed simultaneously. Many cancer types are characterized by altered receptor expression, such as somatostatin receptors, folate receptors or Her2 (human epidermal growth factor receptor 2. Similar correlations are also known for a multitude of transporters, such as glucose transporters, amino acid transporters or hNIS (human sodium iodide symporter, as well as cell specific proteins, such as the prostate specific membrane antigen, integrins, and CD20. This review provides a comprehensive description of the methods, targets and agents used in molecular imaging, to outline their application for cancer stratification. Emphasis is placed on radiotracers which are used to identify altered expression patterns of cancer associated markers.

Sudden Cardiac Risk Stratification with Electrocardiographic Indices - A Review on Computational Processing, Technology Transfer, and Scientific Evidence

Directory of Open Access Journals (Sweden)

Francisco Javier eGimeno-Blanes

2016-03-01

Full Text Available Great effort has been devoted in recent years to the development of sudden cardiac risk predictors as a function of electric cardiac signals, mainly obtained from the electrocardiogram (ECG analysis. But these prediction techniques are still seldom used in clinical practice, partly due to its limited diagnostic accuracy and to the lack of consensus about the appropriate computational signal processing implementation. This paper addresses a three-fold approach, based on ECG indexes, to structure this review on sudden cardiac risk stratification. First, throughout the computational techniques that had been widely proposed for obtaining these indexes in technical literature. Second, over the scientific evidence, that although is supported by observational clinical studies, they are not always representative enough. And third, via the limited technology transfer of academy-accepted algorithms, requiring further meditation for future systems. We focus on three families of ECG derived indexes which are tackled from the aforementioned viewpoints, namely, heart rate turbulence, heart rate variability, and T-wave alternans. In terms of computational algorithms, we still need clearer scientific evidence, standardizing, and benchmarking, siting on advanced algorithms applied over large and representative datasets. New scenarios like electronic health recordings, big data, long-term monitoring, and cloud databases, will eventually open new frameworks to foresee suitable new paradigms in the near future.

The contracting risks of nuclear power engineering and the risk management strategies

International Nuclear Information System (INIS)

Ding Shuying

2010-01-01

With the trend of professional operation on the nuclear power engineering (thereafter using NPE for short) construction, the companies specialized on NPE whole-contracting are established one after the other, the mode of NPE whole-contracting has been wide adopted domestically. As people always concern for the safety of nuclear power, the risks exposed to NPE contractors are also concerned with the operator, the NPE corporations and the society. Therefore, it is very meaningful to analyze on the risks exposed to NPE contractors and the strategies they should take, for it not only determines whether the NPE construction will be finished on time, but also related to sustainable development of the NPE contracting corporations. The main content of this paper includes the analysis on the features and advantages of NPE whole contracting, the major NPE contracting risks, such as nuclear safety risks, strategic risks, market risks, legal risks, financial risks and operation risks, and the strategies to prevent or to control these risks. The paper focuses on identifying those business processes which risks may frequently take place, and how to manage them, illustrating practice cases to explain the theory, in order to make reference to NPE corporations. (author)

Numerical investigation of potential stratification caused by a cryogenic helium spill inside a tunnel

Science.gov (United States)

Sinclair, Cameron; Malecha, Ziemowit; Jedrusyna, Artur

2018-04-01

The sudden release of cryogenic fluid into an accelerator tunnel can pose a significant health and safety risk. For this reason, it is important to evaluate the consequences of such a spill. Previous publications concentrated on either Oxygen Deficiency Hazard or the evaluation of mathematical models using experimental data. No studies to date have focussed on the influence of cryogen inlet conditions on flow development. In this paper, the stratification behaviour of low-temperature helium released into an air-filled accelerator tunnel is investigated for varying helium inlet diameters. A numerical model was constructed using the OpenFOAM Toolbox of a generalised 3D geometry, with similar hydraulic characteristics to the CERN and SLAC tunnels. This model has been validated against published experimental and numerical data. A dimensionless parameter, based on Bakke number, was then determined for the onset of stratification, taking into account the helium inlet diameter; a dimensionless parameter for the degree of stratification was also employed. The simulated flow behaviour is described in terms of these dimensionless parameters, as well as the temperature and oxygen concentration at various heights throughout the tunnel.

Awortwi et al.: Mixing and stratification relationship on phytoplankton ...

African Journals Online (AJOL)

Awortwi et al.: Mixing and stratification relationship on phytoplankton of Lake Bosomtwe (Ghana) 43 West African Journal of Applied Ecology, vol. 23(2), 2015: 43–62. The Relationship Between Mixing and Stratification Regime on the Phytoplankton of Lake Bo.

Has climate change disrupted stratification patterns in Lake Victoria ...

African Journals Online (AJOL)

Has climate change disrupted stratification patterns in Lake Victoria, East Africa? ... Climate change may threaten the fisheries of Lake Victoria by increasing density differentials in the water column, thereby strengthening stratification and increasing the ... Keywords: deoxygenation, fisheries, global warming, thermocline

Thermal stratification and fatigue stress analysis for pressurizer surge line

International Nuclear Information System (INIS)

Yu Xiaofei; Zhang Yixiong

2011-01-01

Thermal stratification of pressurizer surge line induced by the inside fluid results in the global bending moments, local thermal stresses, unexpected displacements and support loadings of the pipe system. In order to avoid a costly three-dimensional computation, a combined 1D/2D technique has been developed and implemented to analyze the thermal stratification and fatigue stress of pressurize surge line of QINSHAN Phase II Extension Nuclear Power Project in this paper, using the computer codes SYSTUS and ROCOCO. According to the mechanical analysis results of stratification, the maximum stress and cumulative usage factor are obtained. The results indicate that the stress and fatigue intensity considering thermal stratification satisfies RCC-M criterion. (authors)

Gastrointestinal stromal tumours: Correlation of modified NIH risk stratification with diffusion-weighted MR imaging as an imaging biomarker

International Nuclear Information System (INIS)

Kang, Tae Wook; Kim, Seong Hyun; Jang, Kyung Mi; Choi, Dongil; Ha, Sang Yun; Kim, Kyoung-Mee; Kang, Won Ki; Kim, Min Ji

2015-01-01

Highlights: • Except size and necrosis, conventional MR findings of GISTs were not significantly different according to the modified NIH criteria. • The ADC values of GISTs were negatively correlated with the modified NIH criteria. • The ADC value can be helpful for the determination of intermediate or high-risk GISTs. - Abstract: Purpose: To evaluate the correlation of risk grade of gastrointestinal stromal tumours (GISTs) based on modified National Institutes of Health (NIH) criteria with conventional magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging. Methods: We included 22 patients with histopathologically proven GISTs in the stomach or small bowel who underwent pre-operative gadoxetic acid-enhanced MR imaging and DW imaging. We retrospectively assessed correlations between morphologic findings, qualitative (signal intensity, consensus from two observers) and quantitative (degree of dynamic enhancement using signal intensity of tumour/muscle ratio and apparent diffusion coefficient [ADC]) values, and the modified NIH criteria for risk stratification. Spearman partial correlation analysis was used to control for tumour size as a confounding factor. The optimal cut-off level of ADC values for intermediate or high risk GISTs was analyzed using a receiver operating characteristic analysis. Results: Except tumour size and necrosis, conventional MR imaging findings, including the degree of dynamic enhancement, were not significantly different according to the modified NIH criteria (p > 0.05). Tumour ADC values were negatively correlated with the modified NIH criteria, before and after adjustment of tumour size (ρ = −0.754; p < 0.001 and ρ = −0.513; p = 0.017, respectively). The optimal cut-off value for the determination of intermediate or high-risk GISTs was 1.279 × 10 −3 mm 2 /s (100% sensitivity, 69.2% specificity, 81.8% accuracy). Conclusion: Except tumour size and necrosis, conventional MR imaging findings did not correlate with

Gastrointestinal stromal tumours: Correlation of modified NIH risk stratification with diffusion-weighted MR imaging as an imaging biomarker

Energy Technology Data Exchange (ETDEWEB)

Kang, Tae Wook [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Kim, Seong Hyun, E-mail: kshyun@skku.edu [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Jang, Kyung Mi; Choi, Dongil [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Ha, Sang Yun; Kim, Kyoung-Mee [Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Kang, Won Ki [Division of Oncology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 135-710 (Korea, Republic of); Kim, Min Ji [Biostatics Unit, Samsung Biomedical Research Institute, Samsung Medical Center, Seoul 135-710 (Korea, Republic of)

2015-01-15

Highlights: • Except size and necrosis, conventional MR findings of GISTs were not significantly different according to the modified NIH criteria. • The ADC values of GISTs were negatively correlated with the modified NIH criteria. • The ADC value can be helpful for the determination of intermediate or high-risk GISTs. - Abstract: Purpose: To evaluate the correlation of risk grade of gastrointestinal stromal tumours (GISTs) based on modified National Institutes of Health (NIH) criteria with conventional magnetic resonance (MR) imaging and diffusion-weighted (DW) imaging. Methods: We included 22 patients with histopathologically proven GISTs in the stomach or small bowel who underwent pre-operative gadoxetic acid-enhanced MR imaging and DW imaging. We retrospectively assessed correlations between morphologic findings, qualitative (signal intensity, consensus from two observers) and quantitative (degree of dynamic enhancement using signal intensity of tumour/muscle ratio and apparent diffusion coefficient [ADC]) values, and the modified NIH criteria for risk stratification. Spearman partial correlation analysis was used to control for tumour size as a confounding factor. The optimal cut-off level of ADC values for intermediate or high risk GISTs was analyzed using a receiver operating characteristic analysis. Results: Except tumour size and necrosis, conventional MR imaging findings, including the degree of dynamic enhancement, were not significantly different according to the modified NIH criteria (p > 0.05). Tumour ADC values were negatively correlated with the modified NIH criteria, before and after adjustment of tumour size (ρ = −0.754; p < 0.001 and ρ = −0.513; p = 0.017, respectively). The optimal cut-off value for the determination of intermediate or high-risk GISTs was 1.279 × 10{sup −3} mm{sup 2}/s (100% sensitivity, 69.2% specificity, 81.8% accuracy). Conclusion: Except tumour size and necrosis, conventional MR imaging findings did not

Communicating cardiovascular disease risk: an interview study of General Practitioners' use of absolute risk within tailored communication strategies.

Science.gov (United States)

Bonner, Carissa; Jansen, Jesse; McKinn, Shannon; Irwig, Les; Doust, Jenny; Glasziou, Paul; McCaffery, Kirsten

2014-05-29

Cardiovascular disease (CVD) prevention guidelines encourage assessment of absolute CVD risk - the probability of a CVD event within a fixed time period, based on the most predictive risk factors. However, few General Practitioners (GPs) use absolute CVD risk consistently, and communication difficulties have been identified as a barrier to changing practice. This study aimed to explore GPs' descriptions of their CVD risk communication strategies, including the role of absolute risk. Semi-structured interviews were conducted with a purposive sample of 25 GPs in New South Wales, Australia. Transcribed audio-recordings were thematically coded, using the Framework Analysis method to ensure rigour. GPs used absolute CVD risk within three different communication strategies: 'positive', 'scare tactic', and 'indirect'. A 'positive' strategy, which aimed to reassure and motivate, was used for patients with low risk, determination to change lifestyle, and some concern about CVD risk. Absolute risk was used to show how they could reduce risk. A 'scare tactic' strategy was used for patients with high risk, lack of motivation, and a dismissive attitude. Absolute risk was used to 'scare' them into taking action. An 'indirect' strategy, where CVD risk was not the main focus, was used for patients with low risk but some lifestyle risk factors, high anxiety, high resistance to change, or difficulty understanding probabilities. Non-quantitative absolute risk formats were found to be helpful in these situations. This study demonstrated how GPs use three different communication strategies to address the issue of CVD risk, depending on their perception of patient risk, motivation and anxiety. Absolute risk played a different role within each strategy. Providing GPs with alternative ways of explaining absolute risk, in order to achieve different communication aims, may improve their use of absolute CVD risk assessment in practice.

European environmental stratifications and typologies

DEFF Research Database (Denmark)

Hazeu, G.W,; Metzger, M.J.; Mücher, C.A.

2011-01-01

their limitations and challenges. As such, they provide a sound basis for describing the factors affecting the robustness of such datasets. The latter is especially relevant, since there is likely to be further interest in European environmental assessment. In addition, advances in data availability and analysis......A range of new spatial datasets classifying the European environment has been constructed over the last few years. These datasets share the common objective of dividing European environmental gradients into convenient units, within which objects and variables of interest have relatively homogeneous...... scale. This paper provides an overview of five recent European stratifications and typologies, constructed for contrasting objectives, and differing in spatial and thematic detail. These datasets are: the Environmental Stratification (EnS), the European Landscape Classification (LANMAP), the Spatial...

Experiments and MPS analysis of stratification behavior of two immiscible fluids

Energy Technology Data Exchange (ETDEWEB)

Li, Gen, E-mail: ligen@fuji.waseda.jp [Cooperative Major in Nuclear Energy, Waseda University, 3-4-1, Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Oka, Yoshiaki [Cooperative Major in Nuclear Energy, Waseda University, 3-4-1, Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Furuya, Masahiro; Kondo, Masahiro [Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwado-kita, Komae, Tokyo 201-8511 (Japan)

2013-12-15

Highlights: • Improving numerical stability of MPS method. • Implicitly calculating viscous term in momentum equation for highly viscous fluids. • Validation of the enhanced MPS method by analyzing dam break problem. • Various stratification behavior analysis by experiments and simulations. • Sensitivity analysis of the effects of the fluid viscosity and density difference. - Abstract: Stratification behavior is of great significance in the late in-vessel stage of core melt severe accident of a nuclear reactor. Conventional numerical methods have difficulties in analyzing stratification process accompanying with free surface without depending on empirical correlations. The Moving Particle Semi-implicit (MPS) method, which calculates free surface and multiphase flow without empirical equations, is applicable for analyzing the stratification behavior of fluids. In the present study, the original MPS method was improved to simulate the stratification behavior of two immiscible fluids. The improved MPS method was validated through simulating classical dam break problem. Then, the stratification processes of two fluid columns and injected fluid were investigated through experiments and simulations, using silicone oil and salt water as the simulant materials. The effects of fluid viscosity and density difference on stratification behavior were also sensitively investigated by simulations. Typical fluid configurations at various parametric and geometrical conditions were observed and well predicted by improved MPS method.

The value of the CHA2DS2-VASc score for refining stroke risk stratification in patients with atrial fibrillation with a CHADS2 score 0-1

DEFF Research Database (Denmark)

Olesen, Jonas Bjerring; Torp-Pedersen, Christian; Hansen, Morten Lock

2012-01-01

associated with increasing CHA2DS2-VASc score was estimated in Cox regression models adjusted for year of inclusion and antiplatelet therapy. The value of adding the extra CHA2DS2-VASc risk factors to the CHADS2 score was evaluated by c-statistics, Net Reclassification Improvement (NRI) and Integrated......DS2-VASc score significantly improved the predictive value of the CHADS2 score alone and a CHA2DS2-VASc score=0 could clearly identify 'truly low risk' subjects. Use of the CHA2DS2-VASc score would significantly improve classification of AF patients at low and intermediate risk of stroke, compared......North American and European guidelines on atrial fibrillation (AF) are conflicting regarding the classification of patients at low/intermediate risk of stroke. We aimed to investigate if the CHA2DS2-VASc score improved risk stratification of AF patients with a CHADS2 score of 0-1. Using individual...

Fuel and combustion stratification study of Partially Premixed Combustion

NARCIS (Netherlands)

Izadi Najafabadi, M.; Dam, N.; Somers, B.; Johansson, B.

2016-01-01

Relatively high levels of stratification is one of the main advantages of Partially Premixed Combustion (PPC) over the Homogeneous Charge Compression Ignition (HCCI) concept. Fuel stratification smoothens heat release and improves controllability of this kind of combustion. However, the lack of a

Relationship between thermal stratification and flow patterns in steam-quenching suppression pool

International Nuclear Information System (INIS)

Song, Daehun; Erkan, Nejdet; Jo, Byeongnam; Okamoto, Koji

2015-01-01

Highlights: • Thermal stratification mechanism by direct contact condensation is investigated. • Thermal stratification condition changes according to the flow pattern. • Thermal stratification depends on the force balance between buoyancy and momentum. • Flow pattern change was observed even in the same regime. • Flow pattern is affected by the sensitive force balance. - Abstract: This study aims to examine the relationship between thermal stratification and flow patterns in a steam-quenching suppression pool using particle image velocimetry. Thermal stratification was experimentally evaluated in a depressurized water pool under different steam mass flux conditions. The time evolution of the temperature profile of the suppression pool was presented with the variation of condensation regimes, and steam condensation processes were visualized using a high-speed camera. The thermal stratification condition was classified into full mixing, gradual thermal stratification, and developed thermal stratification. It was found that the condition was determined by the flow patterns depending on the force balance between buoyancy and momentum. The force balance affected both the condensation regime and the flow pattern, and hence, the flow pattern was changed with the condensation regime. However, the force balance had a sensitive influence on the flow in the pool; therefore, distinct flow patterns were observed even in the same condensation regime.

Managing price risk - setting and implementing strategies

International Nuclear Information System (INIS)

Haines, D.

1999-01-01

The three hedging strategies for price risk management within the natural gas industry are described. The three strategies are: (1) speculative trader (characterized by 'trading for profit, i.e. small margin/large volumes); (2) price optimizer (the objective here is to outperform the market in the establishment of a price); and (3) strategic hedger( the characteristic concern in this strategy is to manage long-term company goals, i.e. balance sheet orientation). The strategies are not mutually exclusive, but overlapping areas can be the source of considerable confusion. Any firm can enter into more than one of these strategies. Integrated companies will adopt very different strategies for upstream versus downstream operations. Details of the three strategies are provided

Risk evaluation mitigation strategies: the evolution of risk management policy.

Science.gov (United States)

Hollingsworth, Kristen; Toscani, Michael

2013-04-01

The United States Food and Drug Administration (FDA) has the primary regulatory responsibility to ensure that medications are safe and effective both prior to drug approval and while the medication is being actively marketed by manufacturers. The responsibility for safe medications prior to marketing was signed into law in 1938 under the Federal Food, Drug, and Cosmetic Act; however, a significant risk management evolution has taken place since 1938. Additional federal rules, entitled the Food and Drug Administration Amendments Act, were established in 2007 and extended the government's oversight through the addition of a Risk Evaluation and Mitigation Strategy (REMS) for certain drugs. REMS is a mandated strategy to manage a known or potentially serious risk associated with a medication or biological product. Reasons for this extension of oversight were driven primarily by the FDA's movement to ensure that patients and providers are better informed of drug therapies and their specific benefits and risks prior to initiation. This article provides an historical perspective of the evolution of medication risk management policy and includes a review of REMS programs, an assessment of the positive and negative aspects of REMS, and provides suggestions for planning and measuring outcomes. In particular, this publication presents an overview of the evolution of the REMS program and its implications.

Polar ocean stratification in a cold climate.

Science.gov (United States)

Sigman, Daniel M; Jaccard, Samuel L; Haug, Gerald H

2004-03-04

The low-latitude ocean is strongly stratified by the warmth of its surface water. As a result, the great volume of the deep ocean has easiest access to the atmosphere through the polar surface ocean. In the modern polar ocean during the winter, the vertical distribution of temperature promotes overturning, with colder water over warmer, while the salinity distribution typically promotes stratification, with fresher water over saltier. However, the sensitivity of seawater density to temperature is reduced as temperature approaches the freezing point, with potential consequences for global ocean circulation under cold climates. Here we present deep-sea records of biogenic opal accumulation and sedimentary nitrogen isotopic composition from the Subarctic North Pacific Ocean and the Southern Ocean. These records indicate that vertical stratification increased in both northern and southern high latitudes 2.7 million years ago, when Northern Hemisphere glaciation intensified in association with global cooling during the late Pliocene epoch. We propose that the cooling caused this increased stratification by weakening the role of temperature in polar ocean density structure so as to reduce its opposition to the stratifying effect of the vertical salinity distribution. The shift towards stratification in the polar ocean 2.7 million years ago may have increased the quantity of carbon dioxide trapped in the abyss, amplifying the global cooling.

Breakup of last glacial deep stratification in the South Pacific

Science.gov (United States)

Basak, Chandranath; Fröllje, Henning; Lamy, Frank; Gersonde, Rainer; Benz, Verena; Anderson, Robert F.; Molina-Kescher, Mario; Pahnke, Katharina

2018-02-01

Stratification of the deep Southern Ocean during the Last Glacial Maximum is thought to have facilitated carbon storage and subsequent release during the deglaciation as stratification broke down, contributing to atmospheric CO2 rise. Here, we present neodymium isotope evidence from deep to abyssal waters in the South Pacific that confirms stratification of the deepwater column during the Last Glacial Maximum. The results indicate a glacial northward expansion of Ross Sea Bottom Water and a Southern Hemisphere climate trigger for the deglacial breakup of deep stratification. It highlights the important role of abyssal waters in sustaining a deep glacial carbon reservoir and Southern Hemisphere climate change as a prerequisite for the destabilization of the water column and hence the deglacial release of sequestered CO2 through upwelling.

GOTHIC code simulation of thermal stratification in POOLEX facility

International Nuclear Information System (INIS)

Li, H.; Kudinov, P.

2009-07-01

Pressure suppression pool is an important element of BWR containment. It serves as a heat sink and steam condenser to prevent containment pressure buildup during loss of coolant accident or safety relief valve opening during normal operations of a BWR. Insufficient mixing in the pool, in case of low mass flow rate of steam, can cause development of thermal stratification and reduction of pressure suppression pool capacity. For reliable prediction of mixing and stratification phenomena validation of simulation tools has to be performed. Data produced in POOLEX/PPOOLEX facility at Lappeenranta University of Technology about development of thermal stratification in a large scale model of a pressure suppression pool is used for GOTHIC lumped and distributed parameter validation. Sensitivity of GOTHIC solution to different boundary conditions and grid convergence study for 2D simulations of POOLEX STB-20 experiment are performed in the present study. CFD simulation was carried out with FLUENT code in order to get additional insights into physics of stratification phenomena. In order to support development of experimental procedures for new tests in the PPOOLEX facility lumped parameter pre-test GOTHIC simulations were performed. Simulations show that drywell and wetwell pressures can be kept within safety margins during a long transient necessary for development of thermal stratification. (au)

GOTHIC code simulation of thermal stratification in POOLEX facility

Energy Technology Data Exchange (ETDEWEB)

Li, H.; Kudinov, P. (Royal Institute of Technology (KTH) (Sweden))

2009-07-15

Pressure suppression pool is an important element of BWR containment. It serves as a heat sink and steam condenser to prevent containment pressure buildup during loss of coolant accident or safety relief valve opening during normal operations of a BWR. Insufficient mixing in the pool, in case of low mass flow rate of steam, can cause development of thermal stratification and reduction of pressure suppression pool capacity. For reliable prediction of mixing and stratification phenomena validation of simulation tools has to be performed. Data produced in POOLEX/PPOOLEX facility at Lappeenranta University of Technology about development of thermal stratification in a large scale model of a pressure suppression pool is used for GOTHIC lumped and distributed parameter validation. Sensitivity of GOTHIC solution to different boundary conditions and grid convergence study for 2D simulations of POOLEX STB-20 experiment are performed in the present study. CFD simulation was carried out with FLUENT code in order to get additional insights into physics of stratification phenomena. In order to support development of experimental procedures for new tests in the PPOOLEX facility lumped parameter pre-test GOTHIC simulations were performed. Simulations show that drywell and wetwell pressures can be kept within safety margins during a long transient necessary for development of thermal stratification. (au)

Non-muscle invasive bladder cancer risk stratification

Directory of Open Access Journals (Sweden)

Sumit Isharwal

2015-01-01

Conclusion: EORTC and CUETO risk tables are the two best-established models to predict recurrence and progression in patients with NMIBC though they tend to overestimate risk and have poor discrimination for prognostic outcomes in external validation. Future research should focus on enhancing the predictive accuracy of risk assessment tools by incorporating additional prognostic factors such as depth of lamina propria invasion and molecular biomarkers after rigorous validation in multi-institutional cohorts.

Coping strategies, stress and risk perception in a natural and industrial catastrophe risk situation

International Nuclear Information System (INIS)

Lopez Vasquez, E.

1998-01-01

People are exposed to different environmental risks, their manifestations harm people according to the magnitude, intensity and the number of people concerned. This subject is very ample, therefore we consider only two kinds of risks: the natural risks (especially earthquakes) that have always threatened humanity, and the industrial risks that characterise our modern society. We are interested in risk perception, stress and coping strategies in these two kinds of extreme situations. We concentrate our study on two Mexican events: an industrial explosion accident in 1984 and 1985 (big earthquake, both devastated big urban zones. The consequences were enormous at all levels: personal, psychological, social, political and economical. Facing risk situations people can have stress reactions when a sign of danger appears. According to Jean RIVOLIER (1994), these situations must not be confounded with banal events of everyday life. Stress in those cases is not the stress we confront everyday, so people have to apply other strategies to face she stress and the incidents of the kind of extreme situations. To tackle our subject we are going to review some concepts used in our study: stress, coping strategies and risk perception. (author)

Approved Risk Evaluation and Mitigation Strategies

Data.gov (United States)

U.S. Department of Health & Human Services — The Food and Drug Administration Amendments Act of 2007 gave FDA the authority to require a Risk Evaluation and Mitigation Strategy (REMS) from manufacturers to...

Risk evaluation and mitigation strategies: a focus on belatacept.

Science.gov (United States)

Sam, Teena; Gabardi, Steven; Tichy, Eric M

2013-03-01

To review the elements and components of the risk evaluation and mitigation strategies (REMS) for the costimulation blocker belatacept and associated implications for health care providers working with transplant recipients. The MEDLINE and EMBASE databases (January 1990 to March 2012) were searched by using risk evaluation and mitigation strategies, REMS, belatacept, and organ transplant as search terms (individual organs were also searched). Retrieved articles were supplemented with analysis of information obtained from the Federal Register, the Food and Drug Administration, and the manufacturer of belatacept. REMS are risk-management strategies implemented to ensure that a product's benefits outweigh its known safety risks. Although belatacept offers a novel strategy in maintenance immunosuppression and was associated with superior renal function compared with cyclosporine in phase 2 and 3 trials, belatacept is also associated with increased risk of posttransplant lymphoproliferative disorder and central nervous system infections. The Food and Drug Administration required development of a REMS program as part of belatacept's approval process to ensure safe and appropriate use of the medication and optimization of its risk-benefit profile. Elements of the belatacept REMS include a medication guide that must be dispensed with each infusion and a communication plan. In the management of a complex population of patients, it is essential that those who care for transplant recipients, and patients, recognize the implications of potential and known risks of belatacept. The REMS program aims to facilitate careful selection and education of patients and vigilant monitoring.

COOPERATION, STRATIFICATION AND RESEARCH DESIGN IN STRATEGY STUDIES IN BRAZIL [doi: 10.5329/RECADM.20100902005] COOPERAÇÃO, ESTRATIFICAÇÃO E PERFIL DA PESQUISA EM ESTRATÉGIA NO BRASIL [doi: 10.5329/RECADM.20100902005

Directory of Open Access Journals (Sweden)

José Bonfim Albuquerque Filho

2010-11-01

Full Text Available The documentary analysis of publications permits to identify scientific production standards associated with characteristics and tendencies expressed in a certain area of knowledge. Considering the area of Strategy in Organizations and its thematic axes, this study analyzed 765 articles published between 2001 and 2006, in the proceedings of EnAnpad’s and 3Es in order to evaluate quantitatively the research design mostly used throughout the period. Moreover, tendencies expressed in terms of stratification standards and cooperation in the area were also investigated. The data were treated in a descriptive-quantitative way, through statistic procedures and multivariate technique of analysis of multiple correspondence. The findings indicated a predominance of a scientific production focused on empirical articles, mainly case studies and surveys. Additionally, the results revealed the growth of the area concerning the number of articles, authors and institutions, accompanied by greater cooperation in scientific production and changes regarding the regional and institutional stratification standards.   Keywords Strategy; scientific production; methodology; cooperation and academic productivity; management Diego M. Coraiola 12.00 Normal 0 21 false false false PT-BR X-NONE X-NONE RESUMO A análise documental de publicações permite identificar características e tendências expressas em determinada área do conhecimento científico. Tendo em vista a área de Estratégia em Organizações, este estudo analisou 765 artigos, publicados entre 2001 e 2006, nos anais dos EnAnpad e 3Es, objetivando avaliar quantitativamente os delineamentos de pesquisa utilizados e analisar tendências acerca dos padrões de estratificação e cooperação na área. Por meio de procedimentos estatísticos e da técnica multivariada de análise de correspondência múltipla, verificou-se a predominância de uma produção científica voltada para artigos empíricos apoiados

The alignment of organisation strategy and risk appetite in the financial services industry

OpenAIRE

2014-01-01

M.Com. (Business Management) This study concerns itself with the concepts of strategy, risk management and risk appetite. Strategy and risk management playa very important role in any business, but it is very difficult to determine the interrelationship between strategy and risk. There is no scientific/academic proof and there is no model or framework on what the alignment between an organisation's strategy and risk appetite is. Therefore, the purpose of this study is to develop a risk app...

Effect of layout on surge line thermal stratification

International Nuclear Information System (INIS)

Lai Jianyong; Huang Wei

2011-01-01

In order to analyze and evaluate the effect of layout on the thermal stratification for PWR Pressurizer surge line, numerical simulation by Computational Fluid Dynamics (CFD) method is taken on 6 kinds of layout improvement with 2 improvement schemes, i.e., increasing the obliquity of quasi horizontal section and adding a vertical pipe between the quasi horizontal section and next elbow, and the maximum temperature differences of quasi horizontal section of surge line of various layouts under different flowrate are obtained. The comparison shows that, the increasing of the obliquity of quasi horizontal section can mitigate the thermal stratification phenomena but can not eliminate this phenomena, while the adding of a vertical pipe between the quasi horizontal section and next elbow can effectively mitigate and eliminate the thermal stratification phenomena. (authors)

Horizontal Stratification in Access to Danish University Programmes

DEFF Research Database (Denmark)

Munk, Martin D.; Thomsen, Jens Peter

2018-01-01

a relatively detailed classification of parents’ occupations to determine how students are endowed with different forms of capital, even when their parents would typically be characterised as belonging to the same social group. Second, we distinguish among disciplines and among university institutions...... to explain the dynamics of horizontal stratification in the Danish university system. Using unique and exhaustive register data, including all higher education institutions and the entire 1984 cohort as of the age of 24, we uncover distinct differences in the magnitude and type of horizontal stratification...... in different fields of study and university institutions. Most importantly, we find distinct patterns of horizontal stratification by field of study and parental occupation that would have remained hidden had we used more aggregated classifications for field of study and social origin....

Cardiovascular risk prediction

DEFF Research Database (Denmark)

Graversen, Peter; Abildstrøm, Steen Z.; Jespersen, Lasse

2016-01-01

Aim European society of cardiology (ESC) guidelines recommend that cardiovascular disease (CVD) risk stratification in asymptomatic individuals is based on the Systematic Coronary Risk Evaluation (SCORE) algorithm, which estimates individual 10-year risk of death from CVD. We assessed the potential...

Stratification in SNR-300 outlet plenum

International Nuclear Information System (INIS)

Reinders, R.

1983-01-01

In the inner outlet plenum of the SNR-300 under steady state conditions a large toroidal vortex is expected. The main flow passes through the gap between dipplate and shield vessel to the outer annular space. Only 3% of the flow pass the 24 emergency cooling holes, situated in the shield vessel. The sodium leaves the reactor tank through the 3 symmetrically arranged outlet nozzles. For a scram flow rates and temperatures are decreased simultaneously, so it is expected, that stratification occurs in the inner outlet plenum. A measure of stratification effects is the Archimedes Number Ar, which is the relation of buoyancy forces (negative) to kinetic energy. (The Archimedes Number is nearly identical with the Richardson Number). For values Ar>1 stratification can occur. Under the assumption of stratification the code TIRE was developed, which is only applicable for the period of time after some 50 sec after scram. This code serves for long term calculations. As the equations are very simple, it is a very fast code which gives the possibility to calculate transients for some hours real time. This code mainly has to take into account the pressure difference between inner plenum and outlet annulus caused by geodatic pressure. That force is in equilibrium with the pressure drop over the gap and holes in the shield vessel. For more detailed calculations of flow pattern and temperature distribution the code MIX and INKO 2T are applied. MIX was developed and validated at ANL, INKO 2T is a development of INTERATOM. INKO 2T is under validation. Mock up experiments were carried out with water to simulate the transient behavior of the SNR-300 outlet plenum. Calculations obtained by INKO 2T for steady state and the transient are shown for the flow pattern. Results of measurements also prove that stratification begins after about 30 sec. Measurements and detailed calculations show that it is admissible to use the code TIRE for the long term calculations. Calculations for a scram

Principal stratification in causal inference.

Science.gov (United States)

Frangakis, Constantine E; Rubin, Donald B

2002-03-01

Many scientific problems require that treatment comparisons be adjusted for posttreatment variables, but the estimands underlying standard methods are not causal effects. To address this deficiency, we propose a general framework for comparing treatments adjusting for posttreatment variables that yields principal effects based on principal stratification. Principal stratification with respect to a posttreatment variable is a cross-classification of subjects defined by the joint potential values of that posttreatment variable tinder each of the treatments being compared. Principal effects are causal effects within a principal stratum. The key property of principal strata is that they are not affected by treatment assignment and therefore can be used just as any pretreatment covariate. such as age category. As a result, the central property of our principal effects is that they are always causal effects and do not suffer from the complications of standard posttreatment-adjusted estimands. We discuss briefly that such principal causal effects are the link between three recent applications with adjustment for posttreatment variables: (i) treatment noncompliance, (ii) missing outcomes (dropout) following treatment noncompliance. and (iii) censoring by death. We then attack the problem of surrogate or biomarker endpoints, where we show, using principal causal effects, that all current definitions of surrogacy, even when perfectly true, do not generally have the desired interpretation as causal effects of treatment on outcome. We go on to forrmulate estimands based on principal stratification and principal causal effects and show their superiority.

Risk mitigation strategy for the ITER electron cyclotron upper port launcher

International Nuclear Information System (INIS)

Goede, A.P.H.; Bongers, W.A.; Elzendoorn, B.S.Q.; Graswinckel, M.F.; Baar, M.R. de

2010-01-01

A basic requirement for ITER equipment to meet is a high level of reliability, because ITER operation time is precious and radioactive operation leaves limited scope for repair. In order to reduce the risk of failure during ITER operation an effective risk mitigation strategy is necessary. This paper presents such strategy for the ITER electron cyclotron upper port launcher (ECUPL). A preliminary ECUPL risk analysis identifies possible failure modes. A probabilistic risk assessment quantifies the risk of failure using a 4 x 4 impact-likelihood matrix. Impact is quantified through technical, cost and schedule elements. Likelihood depends on the risk mitigation strategy adopted. A cost benefit analysis determines the most cost effective risk mitigation strategy. An essential element in risk mitigation is the testing of equipment prior to installation on the ITER machine. This paper argues the need for low- and highpower millimetre wave tests carried out on the fully assembled ECUPL. It presents a conceptual design for a dedicated on-site test bed that can handle 2 of 8 microwave beams at 2 MW long pulse operation.

Predictions of stratification in cold leg components using virtual noding schemes

International Nuclear Information System (INIS)

Piper, R.B.; Hassan, Y.A.; Banerjee, S.S.; Barsamian, H.R.; Cebull, P.P.

1996-01-01

In this investigation, a virtual noding scheme is used with RELAP5/MOD3.2 to capture thermal stratification effects in a small-break loss-of-coolant accident (LOCA) simulation. A three-dimensional code (CFD-ACE) has also been used to observe the stratification effects in a similar situation. Stratification temperature differences of the simulations compare well with that of the experiment. The Froude number was also evaluated

CONSIDERATIONS REGARDING THE MANAGEMENT STRATEGIES OF BANK RISKS

Directory of Open Access Journals (Sweden)

NICOLETA GEORGETA PANAIT

2015-12-01

Full Text Available The study summarizes what it means banking risks, the main risk management strategies. The complexity of the business environment, liberalization and internationalization of financial flows, brings rapid innovation, diversified financial markets, new opportunities but multiplied risks. Banks establish the types of risks they are prepared to take and the threshold at which risk is considered significant. The process of determining the risks that are taken includes the nature, the scale and the complexity of banks.

Current indications for transplantation: stratification of severe heart failure and shared decision-making.

Science.gov (United States)

Vucicevic, Darko; Honoris, Lily; Raia, Federica; Deng, Mario

2018-01-01

Heart failure (HF) is a complex clinical syndrome that results from structural or functional cardiovascular disorders causing a mismatch between demand and supply of oxygenated blood and consecutive failure of the body's organs. For those patients with stage D HF, advanced therapies, such as mechanical circulatory support (MCS) or heart transplantation (HTx), are potentially life-saving options. The role of risk stratification of patients with stage D HF in a value-based healthcare framework is to predict which subset might benefit from advanced HF (AdHF) therapies, to improve outcomes related to the individual patient including mortality, morbidity and patient experience as well as to optimize health care delivery system outcomes such as cost-effectiveness. Risk stratification and subsequent outcome prediction as well as therapeutic recommendation-making need to be based on the comparative survival benefit rationale. A robust model needs to (I) have the power to discriminate (i.e., to correctly risk stratify patients); (II) calibrate (i.e., to show agreement between the predicted and observed risk); (III) to be applicable to the general population; and (IV) provide good external validation. The Seattle Heart Failure Model (SHFM) and the Heart Failure Survival Score (HFSS) are two of the most widely utilized scores. However, outcomes for patients with HF are highly variable which make clinical predictions challenging. Despite our clinical expertise and current prediction tools, the best short- and long-term survival for the individual patient, particularly the sickest patient, is not easy to identify because among the most severely ill, elderly and frail patients, most preoperative prediction tools have the tendency to be imprecise in estimating risk. They should be used as a guide in a clinical encounter grounded in a culture of shared decision-making, with the expert healthcare professional team as consultants and the patient as an empowered decision-maker in a

Risk evaluation and control strategies for indoor radon: a brief discussion

International Nuclear Information System (INIS)

Nero, A.V. Jr.

1994-01-01

Average risks of death estimated for radon are larger than those for many exposures in the outdoor environment, but similar to some in industrial settings. However, the indoor environment differs in regard to cost, benefit, responsibility, and distribution of risks from the outdoor and occupational settings, where frameworks for setting risk-limiting objectives and strategies have already been developed substantially. This indicates the need to develop a conceptual framework for evaluating risks in the indoor environment, within which the objectives of radon control strategies can be sensibly chosen. Nevertheless, the range of estimated radon risks and of recent radon control strategies suggest near-term elements of any strategy, i.e. accurate and effective public information, as well as reliable monitoring and control capabilities, and a focus on areas where most high residential levels occur. Developing a conceptual framework for evaluating indoor risks will permit the formulation of suitable aims on average indoor exposures and lower exposure situations. (author)

Temperature Stratification in a Cryogenic Fuel Tank

Science.gov (United States)

Daigle, Matthew John; Smelyanskiy, Vadim; Boschee, Jacob; Foygel, Michael Gregory

2013-01-01

A reduced dynamical model describing temperature stratification effects driven by natural convection in a liquid hydrogen cryogenic fuel tank has been developed. It accounts for cryogenic propellant loading, storage, and unloading in the conditions of normal, increased, and micro- gravity. The model involves multiple horizontal control volumes in both liquid and ullage spaces. Temperature and velocity boundary layers at the tank walls are taken into account by using correlation relations. Heat exchange involving the tank wall is considered by means of the lumped-parameter method. By employing basic conservation laws, the model takes into consideration the major multi-phase mass and energy exchange processes involved, such as condensation-evaporation of the hydrogen, as well as flows of hydrogen liquid and vapor in the presence of pressurizing helium gas. The model involves a liquid hydrogen feed line and a tank ullage vent valve for pressure control. The temperature stratification effects are investigated, including in the presence of vent valve oscillations. A simulation of temperature stratification effects in a generic cryogenic tank has been implemented in Matlab and results are presented for various tank conditions.

Drainage and Stratification Kinetics of Foam Films

Science.gov (United States)

Zhang, Yiran; Sharma, Vivek

2014-03-01

Baking bread, brewing cappuccino, pouring beer, washing dishes, shaving, shampooing, whipping eggs and blowing bubbles all involve creation of aqueous foam films. Foam lifetime, drainage kinetics and stability are strongly influenced by surfactant type (ionic vs non-ionic), and added proteins, particles or polymers modify typical responses. The rate at which fluid drains out from a foam film, i.e. drainage kinetics, is determined in the last stages primarily by molecular interactions and capillarity. Interestingly, for certain low molecular weight surfactants, colloids and polyelectrolyte-surfactant mixtures, a layered ordering of molecules, micelles or particles inside the foam films leads to a stepwise thinning phenomena called stratification. Though stratification is observed in many confined systems including foam films containing particles or polyelectrolytes, films containing globular proteins seem not to show this behavior. Using a Scheludko-type cell, we experimentally study the drainage and stratification kinetics of horizontal foam films formed by protein-surfactant mixtures, and carefully determine how the presence of proteins influences the hydrodynamics and thermodynamics of foam films.

Comparison of EHR-based diagnosis documentation locations to a gold standard for risk stratification in patients with multiple chronic conditions.

Science.gov (United States)

Martin, Shelby; Wagner, Jesse; Lupulescu-Mann, Nicoleta; Ramsey, Katrina; Cohen, Aaron; Graven, Peter; Weiskopf, Nicole G; Dorr, David A

2017-08-02

To measure variation among four different Electronic Health Record (EHR) system documentation locations versus 'gold standard' manual chart review for risk stratification in patients with multiple chronic illnesses. Adults seen in primary care with EHR evidence of at least one of 13 conditions were included. EHRs were manually reviewed to determine presence of active diagnoses, and risk scores were calculated using three different methodologies and five EHR documentation locations. Claims data were used to assess cost and utilization for the following year. Descriptive and diagnostic statistics were calculated for each EHR location. Criterion validity testing compared the gold standard verified diagnoses versus other EHR locations and risk scores in predicting future cost and utilization. Nine hundred patients had 2,179 probable diagnoses. About 70% of the diagnoses from the EHR were verified by gold standard. For a subset of patients having baseline and prediction year data (n=750), modeling showed that the gold standard was the best predictor of outcomes on average for a subset of patients that had these data. However, combining all data sources together had nearly equivalent performance for prediction as the gold standard. EHR data locations were inaccurate 30% of the time, leading to improvement in overall modeling from a gold standard from chart review for individual diagnoses. However, the impact on identification of the highest risk patients was minor, and combining data from different EHR locations was equivalent to gold standard performance. The reviewer's ability to identify a diagnosis as correct was influenced by a variety of factors, including completeness, temporality, and perceived accuracy of chart data.

Identification and risk estimation of movement strategies during cutting maneuvers.

Science.gov (United States)

David, Sina; Komnik, Igor; Peters, Markus; Funken, Johannes; Potthast, Wolfgang

2017-12-01

Approximately 70% of anterior cruciate ligament (ACL) injuries occur in non-contact situations during cutting and landing maneuvers. Parameters such as footstrike patterns and trunk orientation were found to influence ACL relevant knee loading, however, the relationship between the whole body movement and injury risk is debated. This study identifies whole body movement strategies that increase injury risk, and provides training recommendations to reduce this risk or enable a save return to sports after injury. Experimental cross-sectional study design. Three dimensional movement analysis was carried out to investigate 50 participants performing anticipated 90° cutting maneuvers. To identify and characterize movement strategies, footstrike pattern, knee valgus moment, knee internal rotation moment, angle of attack, shoulder and pelvis axis were analyzed using statistical parametric mapping. Three different movement strategies were identified. One strategy included rearfoot striking in combination with a relatively upright body position which generated higher knee joint loads than the second strategy, forefoot striking in combination with more backwards leaning and pre-rotation of the trunk towards the new movement direction. A third strategy combined forefoot striking with less preorientation which increased the ACL relevant knee joint load compared to the second strategy. The identified movement strategies clearly pre-determine the injury risk during non-contact situations with the third strategy as the most unfavorable one. Compared to the study of isolated parameters, the analysis of the whole body movement allowed for detailed separation of more risky from less risky cutting strategies. These results give practical recommendations for the prevention of ACL injury. Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

A risk hedging strategy under the nonparallel-shift yield curve

Science.gov (United States)

Gong, Pu; He, Xubiao

2005-08-01

Under the assumption of the movement of rigid, a nonparallel-shift model in the term structure of interest rates is developed by introducing Fisher & Weil duration which is a well-known concept in the area of interest risk management. This paper has studied the hedge and replication for portfolio immunization to minimize the risk exposure. Throughout the experiment of numerical simulation, the risk exposures of the portfolio under the different risk hedging strategies are quantitatively evaluated by the method of value at risk (VaR) order statistics (OS) estimation. The results show that the risk hedging strategy proposed in this paper is very effective for the interest risk management of the default-free bond.

Understanding PSA and its derivatives in prediction of tumor volume: Addressing health disparities in prostate cancer risk stratification.

Science.gov (United States)

Chinea, Felix M; Lyapichev, Kirill; Epstein, Jonathan I; Kwon, Deukwoo; Smith, Paul Taylor; Pollack, Alan; Cote, Richard J; Kryvenko, Oleksandr N

2017-03-28

To address health disparities in risk stratification of U.S. Hispanic/Latino men by characterizing influences of prostate weight, body mass index, and race/ethnicity on the correlation of PSA derivatives with Gleason score 6 (Grade Group 1) tumor volume in a diverse cohort. Using published PSA density and PSA mass density cutoff values, men with higher body mass indices and prostate weights were less likely to have a tumor volume PSA derivatives when predicting for tumor volume. In receiver operator characteristic analysis, area under the curve values for all PSA derivatives varied across race/ethnicity with lower optimal cutoff values for Hispanic/Latino (PSA=2.79, PSA density=0.06, PSA mass=0.37, PSA mass density=0.011) and Non-Hispanic Black (PSA=3.75, PSA density=0.07, PSA mass=0.46, PSA mass density=0.008) compared to Non-Hispanic White men (PSA=4.20, PSA density=0.11 PSA mass=0.53, PSA mass density=0.014). We retrospectively analyzed 589 patients with low-risk prostate cancer at radical prostatectomy. Pre-operative PSA, patient height, body weight, and prostate weight were used to calculate all PSA derivatives. Receiver operating characteristic curves were constructed for each PSA derivative per racial/ethnic group to establish optimal cutoff values predicting for tumor volume ≥0.5 cm3. Increasing prostate weight and body mass index negatively influence PSA derivatives for predicting tumor volume. PSA derivatives' ability to predict tumor volume varies significantly across race/ethnicity. Hispanic/Latino and Non-Hispanic Black men have lower optimal cutoff values for all PSA derivatives, which may impact risk assessment for prostate cancer.

Germination and development of pecan cultivar seedlings by seed stratification

Directory of Open Access Journals (Sweden)

Igor Poletto

2015-12-01

Full Text Available Abstract: The objective of this work was to evaluate the effect of seed stratification on germination rate, germination speed, and initial development of seedlings of six pecan (Carya illinoinensis cultivars under subtropical climatic conditions in southern Brazil. For stratification, the seeds were placed in boxes with moist sand, in a cold chamber at 4°C, for 90 days. In the fourteenth week after sowing, the emergence speed index, total emergence, plant height, stem diameter, and number of leaves were evaluated. Seed stratification significantly improves the germination potential and morphological traits of the evaluated cultivars.

Evaluation of different hedging strategies for commodity price risks of industrial cogeneration plants

International Nuclear Information System (INIS)

Palzer, Andreas; Westner, Günther; Madlener, Reinhard

2013-01-01

In this paper, we design and evaluate eight different strategies for hedging commodity price risks of industrial cogeneration plants. Price developments are parameterized based on EEX data from 2008 to 2011. The probability distributions derived are used to determine the value-at-risk (VaR) of the individual strategies, which are in a final step combined in a mean-variance portfolio analysis for determining the most efficient hedging strategy. We find that the strategy adopted can have a marked influence on the remaining price risk. Quarter futures are found to be particularly well suited for reducing market price risk. In contrast, spot trading of CO 2 certificates is found to be preferable compared to forward market trading. Finally, portfolio optimization shows that a mix of various hedging strategies can further improve the profitability of a heat-based cogeneration plant. - Highlights: • Evaluation of commodity price risk hedging strategies for industrial cogeneration. • Value-at-risk analysis of eight different hedging strategies. • Mean-variance portfolio analysis for determining the optimal hedging strategy mix. • A mix of hedging strategies further improves profitability of heat-based CHP

Eddy-driven stratification initiates North Atlantic spring phytoplankton blooms.

Science.gov (United States)

Mahadevan, Amala; D'Asaro, Eric; Lee, Craig; Perry, Mary Jane

2012-07-06

Springtime phytoplankton blooms photosynthetically fix carbon and export it from the surface ocean at globally important rates. These blooms are triggered by increased light exposure of the phytoplankton due to both seasonal light increase and the development of a near-surface vertical density gradient (stratification) that inhibits vertical mixing of the phytoplankton. Classically and in current climate models, that stratification is ascribed to a springtime warming of the sea surface. Here, using observations from the subpolar North Atlantic and a three-dimensional biophysical model, we show that the initial stratification and resulting bloom are instead caused by eddy-driven slumping of the basin-scale north-south density gradient, resulting in a patchy bloom beginning 20 to 30 days earlier than would occur by warming.

Near-Surface Effects of Free Atmosphere Stratification in Free Convection

NARCIS (Netherlands)

Mellado, Juan Pedro; Heerwaarden, van C.C.; Garcia, Jade Rachele

2016-01-01

The effect of a linear stratification in the free atmosphere on near-surface properties in a free convective boundary layer (CBL) is investigated by means of direct numerical simulation. We consider two regimes: a neutral stratification regime, which represents a CBL that grows into a residual

Histological Stratification of Thick and Thin Plaque Psoriasis Explores Molecular Phenotypes with Clinical Implications

Science.gov (United States)

Kim, Dong Joo; Brodmerkel, Carrie; Correa da Rosa, Joel; Krueger, James G.; Suárez-Fariñas, Mayte

2015-01-01

Psoriasis, which presents as red, scaly patches on the body, is a common, autoimmune skin disease that affects 2 to 3 percent of the world population. To leverage recent molecular findings into the personalized treatment of psoriasis, we need a strategy that integrates clinical stratification with molecular phenotyping. In this study, we sought to stratify psoriasis patients by histological measurements of epidermal thickness, and to compare their molecular characterizations by gene expression, serum cytokines, and response to biologics. We obtained histological measures of epidermal thickness in a cohort of 609 psoriasis patients, and identified a mixture of two subpopulations—thick and thin plaque psoriasis—from which they were derived. This stratification was verified in a subcohort of 65 patients from a previously published study with significant differences in inflammatory cell infiltrates in the psoriatic skin. Thick and thin plaque psoriasis shared 84.8% of the meta-analysis-derived psoriasis transcriptome, but a stronger dysregulation of the meta-analysis-derived psoriasis transcriptome was seen in thick plaque psoriasis on microarray. RT-PCR revealed that gene expression in thick and thin plaque psoriasis was different not only within psoriatic lesional skin but also in peripheral non-lesional skin. Additionally, differences in circulating cytokines and their changes in response to biologic treatments were found between the two subgroups. All together, we were able to integrate histological stratification with molecular phenotyping as a way of exploring clinical phenotypes with different expression levels of the psoriasis transcriptome and circulating cytokines. PMID:26176783

PORTFOLIO INSURANCE INVESTMENT STRATEGIES: A RISK-MANAGEMENT TOOL

Directory of Open Access Journals (Sweden)

Elma Agic-Sabeta

2017-06-01

Full Text Available Unsystemic risks in financial markets may be reduced through diversification. Systemic risks relate to the overall economy, cannot be influenced by a single company, and require special attention. Empirical research on return distributions in the long-term shows that investing under the assumption of normal distribution of returns may be dangerous. The main objectives of this article are to describe portfolio insurance strategies and investigate their advantages and disadvantages. Furthermore, their use in financial markets in both developed and emerging markets is explored, with special consideration placed on southeast European markets. Theoretical models are reviewed, including recent research articles in the field. The results are analyzed, summarized, and presented in the form of tables and graphs. The main finding of the article is identification of strategies that could be used in southeast Europe. It concludes that implementation of portfolio insurance strategies by asset managers may reduce financial risks in southeast European markets if implementation is done professionally and, simultaneously, it is monitored during the entire investment horizon.

Improving risk stratification for cardiovascular disease

NARCIS (Netherlands)

van Wijk, Diederik F.; Boekholdt, S. Matthijs

2010-01-01

Evaluation of: Heslop CL, Frohlich JJ, Hill JS. Myeloperoxidase and C-reactive protein have combined utility for long-term prediction of cardiovascular mortality after coronary angiography. J. Am. Coll. Cardiol. 55(11), 1102-1109 (2010). Identifying people at high risk of cardiovascular events is

The Effect of Barotropic and Baroclinic Tides on Coastal Stratification and Mixing

Science.gov (United States)

Suanda, S. H.; Feddersen, F.; Kumar, N.

2017-12-01

The effects of barotropic and baroclinic tides on subtidal stratification and vertical mixing are examined with high-resolution, three-dimensional numerical simulations of the Central Californian coastal upwelling region. A base simulation with realistic atmospheric and regional-scale boundary forcing but no tides (NT) is compared to two simulations with the addition of predominantly barotropic local tides (LT) and with combined barotropic and remotely generated, baroclinic tides (WT) with ≈ 100 W m-1 onshore baroclinic energy flux. During a 10 day period of coastal upwelling when the domain volume-averaged temperature is similar in all three simulations, LT has little difference in subtidal temperature and stratification compared to NT. In contrast, the addition of remote baroclinic tides (WT) reduces the subtidal continental shelf stratification up to 50% relative to NT. Idealized simulations to isolate barotropic and baroclinic effects demonstrate that within a parameter space of typical U.S. West Coast continental shelf slopes, barotropic tidal currents, incident energy flux, and subtidal stratification, the dissipating baroclinic tide destroys stratification an order of magnitude faster than barotropic tides. In WT, the modeled vertical temperature diffusivity at the top (base) of the bottom (surface) boundary layer is increased up to 20 times relative to NT. Therefore, the width of the inner-shelf (region of surface and bottom boundary layer overlap) is increased approximately 4 times relative to NT. The change in stratification due to dissipating baroclinic tides is comparable to the magnitude of the observed seasonal cycle of stratification.

Revealing the timing of ocean stratification using remotely-sensed ocean fronts: links with marine predators

Science.gov (United States)

Miller, P. I.; Loveday, B. R.

2016-02-01

Stratification is of critical importance to the mixing and productivity of the ocean, though currently it can only be measured using in situ sampling, profiling buoys or underwater autonomous vehicles. Stratification is understood to affect the surface aggregation of pelagic fish and hence the foraging behaviour and distribution of their predators such as seabirds and cetaceans. Satellite Earth observation sensors cannot directly detect stratification, but can observe surface features related to the presence of stratification, for example shelf-sea fronts that separate tidally-mixed water from seasonally stratified water. This presentation describes a novel algorithm that accumulates evidence for stratification from a sequence of oceanic front maps, and in certain regions can reveal the timing of the seasonal onset and breakdown of stratification. Initial comparisons will be made with seabird locations acquired through GPS tagging. If successful, a remotely-sensed stratification timing index would augment the ocean front metrics already developed at PML, that have been applied in over 20 journal articles relating marine predators to ocean fronts. The figure below shows a preliminary remotely-sensed 'stratification' index, for 25-31 Jul. 2010, where red indicates water with stronger evidence for stratification.

PPOOLEX experiments on thermal stratification and mixing

Energy Technology Data Exchange (ETDEWEB)

Puustinen, M.; Laine, J.; Raesaenen, A. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

2009-08-15

The results of the thermal stratification experiments in 2008 with the PPOOLEX test facility are presented. PPOOLEX is a closed vessel divided into two compartments, dry well and wet well. Extra temperature measurements for capturing different aspects of the investigated phenomena were added before the experiments. The main purpose of the experiment series was to generate verification data for evaluating the capability of GOTHIC code to predict stratification and mixing phenomena. Altogether six experiments were carried out. Heat-up periods of several thousand seconds by steam injection into the dry well compartment and from there into the wet well water pool were recorded. The initial water bulk temperature was 20 deg. C. Cooling periods of several days were included in three experiments. A large difference between the pool bottom and top layer temperature was measured when small steam flow rates were used. With higher flow rates the mixing effect of steam discharge delayed the start of stratification until the pool bulk temperature exceeded 50 deg. C. The stratification process was also different in these two cases. With a small flow rate stratification was observed only above and just below the blowdown pipe outlet elevation. With a higher flow rate over a 30 deg. C temperature difference between the pool bottom and pipe outlet elevation was measured. Elevations above the pipe outlet indicated almost linear rise until the end of steam discharge. During the cooling periods the measurements of the bottom third of the pool first had an increasing trend although there was no heat input from outside. This was due to thermal diffusion downwards from the higher elevations. Heat-up in the gas space of the wet well was quite strong, first due to compression by pressure build-up and then by heat conduction from the hot dry well compartment via the intermediate floor and test vessel walls and by convection from the upper layers of the hot pool water. The gas space

PPOOLEX experiments on thermal stratification and mixing

International Nuclear Information System (INIS)

Puustinen, M.; Laine, J.; Raesaenen, A.

2009-08-01

The results of the thermal stratification experiments in 2008 with the PPOOLEX test facility are presented. PPOOLEX is a closed vessel divided into two compartments, dry well and wet well. Extra temperature measurements for capturing different aspects of the investigated phenomena were added before the experiments. The main purpose of the experiment series was to generate verification data for evaluating the capability of GOTHIC code to predict stratification and mixing phenomena. Altogether six experiments were carried out. Heat-up periods of several thousand seconds by steam injection into the dry well compartment and from there into the wet well water pool were recorded. The initial water bulk temperature was 20 deg. C. Cooling periods of several days were included in three experiments. A large difference between the pool bottom and top layer temperature was measured when small steam flow rates were used. With higher flow rates the mixing effect of steam discharge delayed the start of stratification until the pool bulk temperature exceeded 50 deg. C. The stratification process was also different in these two cases. With a small flow rate stratification was observed only above and just below the blowdown pipe outlet elevation. With a higher flow rate over a 30 deg. C temperature difference between the pool bottom and pipe outlet elevation was measured. Elevations above the pipe outlet indicated almost linear rise until the end of steam discharge. During the cooling periods the measurements of the bottom third of the pool first had an increasing trend although there was no heat input from outside. This was due to thermal diffusion downwards from the higher elevations. Heat-up in the gas space of the wet well was quite strong, first due to compression by pressure build-up and then by heat conduction from the hot dry well compartment via the intermediate floor and test vessel walls and by convection from the upper layers of the hot pool water. The gas space

Strain Echocardiography Improves Risk Prediction of Ventricular Arrhythmias After Myocardial Infarction

DEFF Research Database (Denmark)

Haugaa, Kristina H; Grenne, Bjørnar L; Eek, Christian H

2013-01-01

The aim of this study was to test the hypothesis that strain echocardiography might improve arrhythmic risk stratification in patients after myocardial infarction (MI).......The aim of this study was to test the hypothesis that strain echocardiography might improve arrhythmic risk stratification in patients after myocardial infarction (MI)....

Temperature stratification in a hot water tank with circulation pipe

DEFF Research Database (Denmark)

Andersen, Elsa

1998-01-01

The aim of the project is to investigate the change in temperature stratification due to the operation of a circulation pipe. Further, putting forward rules for design of pipe inlet in order not to disturb the temperature stratification in the hot water tank. A validated computer model based on t...

Biological Risks to Public Health: Lessons from an International Conference to Inform the Development of National Risk Communication Strategies.

Science.gov (United States)

Dickmann, Petra; Bhatiasevi, Aphaluck; Chaib, Fadela; Baggio, Ombretta; Banluta, Christina; Hollenweger, Lilian; Maaroufi, Abderrahmane

Biological risk management in public health focuses on the impact of outbreaks on health, the economy, and other systems and on ensuring biosafety and biosecurity. To address this broad range of risks, the International Health Regulations (IHR, 2005) request that all member states build defined core capacities, risk communication being one of them. While there is existing guidance on the communication process and on what health authorities need to consider to design risk communication strategies that meet the requirements on a governance level, little has been done on implementation because of a number of factors, including lack of resources (human, financial, and others) and systems to support effective and consistent capacity for risk communication. The international conference on "Risk communication strategies before, during and after public health emergencies" provided a platform to present current strategies, facilitate learning from recent outbreaks of infectious diseases, and discuss recommendations to inform risk communication strategy development. The discussion concluded with 4 key areas for improvement in risk communication: consider communication as a multidimensional process in risk communication, broaden the biomedical paradigm by integrating social science intelligence into epidemiologic risk assessments, strengthen multisectoral collaboration including with local organizations, and spearhead changes in organizations for better risk communication governance. National strategies should design risk communication to be proactive, participatory, and multisectoral, facilitating the connection between sectors and strengthening collaboration.

Environmental stratification framework and water-quality monitoring design strategy for the Islamic Republic of Mauritania, Africa

Science.gov (United States)

Friedel, Michael J.

2008-01-01

Mauritania anticipates an increase in mining activities throughout the country and into the foreseeable future. Because mining-induced changes in the landscape are likely to affect their limited ground-water resources and sensitive aquatic ecosystems, a water-quality assessment program was designed for Mauritania that is based on a nationally consistent environmental stratification framework. The primary objectives of this program are to ensure that the environmental monitoring systems can quantify near real-time changes in surface-water chemistry at a local scale, and quantify intermediate- to long-term changes in groundwater and aquatic ecosystems over multiple scales.

Experimental study on the thermal stratification in the branch of NPP

Energy Technology Data Exchange (ETDEWEB)

Kim, Sang Nyung; Hwang, Seong Hong [Kyunghee Univ., Seoul (Korea, Republic of)

2004-02-15

As more experience is accumulated in the operation of existing nuclear power plants, the long term effects of thermal-hydraulic phenomena, unaccounted in the original designs, have been observed. One such phenomenon is thermal stratification, which has caused through-wall cracks, thermal fatigue, unexpected piping displacements and pipe support damage. Thermal stratification is a phenomenon as temperature layers are formed in the component or piping due to the density difference between hot and cold water. The thermal stratification phenomena in nuclear power plant observed in the pressurizer surge line, and in the piping of feedwater system, Safety Injection System(SIS), residual heat removal system (or shutdown cooling system), and chemical and volume control system during the design transients. A set of experiment has been performed to predict the temperature distribution in the branch piping of nuclear power plant(Ulchin unit 3 and 4) due to the turbulent penetration, the heat transfer through valve disk and valve leakage. The test facility scaled down to 1/10 has been designed and constructed to simulate the thermal stratification in the piping of safety injection system and shutdown cooling system of Ulchin 3 and 4. The experimental results show that the turbulent penetration depth could be : extended to the end of the vertical pipe, and thermal stratification due to the heat transfer through the valve disk to the end of horizontal pipe behind the valve disk. Finally, thermal stratification could effected by the location of valve leakage.

Molecular reclassification of Crohn's disease: a cautionary note on population stratification.

Science.gov (United States)

Maus, Bärbel; Jung, Camille; Mahachie John, Jestinah M; Hugot, Jean-Pierre; Génin, Emmanuelle; Van Steen, Kristel

2013-01-01

Complex human diseases commonly differ in their phenotypic characteristics, e.g., Crohn's disease (CD) patients are heterogeneous with regard to disease location and disease extent. The genetic susceptibility to Crohn's disease is widely acknowledged and has been demonstrated by identification of over 100 CD associated genetic loci. However, relating CD subphenotypes to disease susceptible loci has proven to be a difficult task. In this paper we discuss the use of cluster analysis on genetic markers to identify genetic-based subgroups while taking into account possible confounding by population stratification. We show that it is highly relevant to consider the confounding nature of population stratification in order to avoid that detected clusters are strongly related to population groups instead of disease-specific groups. Therefore, we explain the use of principal components to correct for population stratification while clustering affected individuals into genetic-based subgroups. The principal components are obtained using 30 ancestry informative markers (AIM), and the first two PCs are determined to discriminate between continental origins of the affected individuals. Genotypes on 51 CD associated single nucleotide polymorphisms (SNPs) are used to perform latent class analysis, hierarchical and Partitioning Around Medoids (PAM) cluster analysis within a sample of affected individuals with and without the use of principal components to adjust for population stratification. It is seen that without correction for population stratification clusters seem to be influenced by population stratification while with correction clusters are unrelated to continental origin of individuals.

Molecular reclassification of Crohn's disease: a cautionary note on population stratification.

Directory of Open Access Journals (Sweden)

Bärbel Maus

Full Text Available Complex human diseases commonly differ in their phenotypic characteristics, e.g., Crohn's disease (CD patients are heterogeneous with regard to disease location and disease extent. The genetic susceptibility to Crohn's disease is widely acknowledged and has been demonstrated by identification of over 100 CD associated genetic loci. However, relating CD subphenotypes to disease susceptible loci has proven to be a difficult task. In this paper we discuss the use of cluster analysis on genetic markers to identify genetic-based subgroups while taking into account possible confounding by population stratification. We show that it is highly relevant to consider the confounding nature of population stratification in order to avoid that detected clusters are strongly related to population groups instead of disease-specific groups. Therefore, we explain the use of principal components to correct for population stratification while clustering affected individuals into genetic-based subgroups. The principal components are obtained using 30 ancestry informative markers (AIM, and the first two PCs are determined to discriminate between continental origins of the affected individuals. Genotypes on 51 CD associated single nucleotide polymorphisms (SNPs are used to perform latent class analysis, hierarchical and Partitioning Around Medoids (PAM cluster analysis within a sample of affected individuals with and without the use of principal components to adjust for population stratification. It is seen that without correction for population stratification clusters seem to be influenced by population stratification while with correction clusters are unrelated to continental origin of individuals.

Is the high-risk strategy to prevent cardiovascular disease equitable?

DEFF Research Database (Denmark)

Wallach Kildemoes, Helle; Diderichsen, Finn; Krasnik, Allan

2012-01-01

ABSTRACT: BACKGROUND: Statins are increasingly prescribed to prevent cardiovascular disease (CVD) in asymptomatic individuals. Yet, it is unknown whether those at higher CVD risk - i.e. individuals in lower socio-economic position (SEP) - are adequately reached by this high-risk strategy. Aim......: To examine whether the Danish implementation of the strategy to prevent cardiovascular disease (CVD) by initiating statin (HMG-CoA reductase inhibitor) therapy in high-risk individuals is equitable across socioeconomic groups. METHODS: Design: Cohort study. Setting and participants: Applying individual...

[Prediction value of deceleration capacity of rate and GRACE risk score on major adverse cardiac events in patients with acute myocardial infarction].

Science.gov (United States)

Gao, L; Chen, Y D; Shi, Y J; Xue, H; Wang, J L

2016-07-24

To investigate the prediction value of deceleration capacity of rate (DC) and GRACE risk score for cardiovascular events in AMI patients. Consecutive AMI patients with sinus rhythm hospitalized in our department during August 2012 to August 2013 were included in this prospective study. 24-hour ECG Holter monitoring was performed within 1 week, and the DC value was analyzed, GRACE risk score was acquired with the application of GRACE risk score calculator. Patients were followed up for more than 1 year and major adverse cardiac events (MACE) were obtained. Analysised the Kaplan Meier survival according to DC and GRACE score risk stratification respectively. A total of 157 patients were enrolled in the study (average age: (58.9±12.7)years old). The average follow-up was (20.54±2.85) months. Mortality during follow-up was significantly higher in patients with DC>2.5 compared to patients with DC≤2.5 (Prisk stratification was 0.898 (95%CI 0.840-0.940, Prisk stratification was 0.786 (95%CI 0.714-0.847, Prisk stratification was 0.708 (95%CI 0.652-0.769, Prisk patients than those with intermediate and low risk patients according to DC risk stratification in intermediate and low risk patients by GRACE risk stratification (Prisk stratification is superior to GRACE risk score on outcome assessment in this AMI patient cohort.

EPA'S strategy to reduce risk of radon

International Nuclear Information System (INIS)

Page, S.

1993-01-01

The Indoor Radon Abatement Act of 1988 (IRAA) directed EPA to undertake a variety of activities to address the growing public concern over dangers posed by exposure to indoor radon. Among other requirements, the law directed the Agency to study radon levels, evaluate mitigation methods, establish proficiency programs, assist states with program development, develop training centers, and provide public information. EPA has developed and implemented programs to address each of the key provisions of this statute. This paper presents EPA's broad national strategy to reduce radon risks. It combines and reinforces EPA's basic foundation, including its guiding policies and cooperative partnerships, with an overall management approach and focus for the future. The paper starts with an overview that introduces the strategy's four key elements: underlying policies and scientific principles, a decentralized system of states and other partners for targeting the public, multiple strategies for achieving radon risk reduction, and a strong focus on five key program priorities. This paper then discusses each of these elements in more detail and describes how they interact to guide future efforts and directions of the Agency

Glaucoma and quality of life: fall and driving risk.

Science.gov (United States)

Montana, Cynthia L; Bhorade, Anjali M

2018-03-01

Numerous population-based studies suggest that glaucoma is an independent risk factor for falling and motor vehicle collisions, particularly for older adults. These adverse events lead to increased healthcare expenditures and decreased quality of life. Current research priorities, therefore, include identifying factors that predispose glaucoma patients to falling and unsafe driving, and developing screening strategies and targeted rehabilitation. The purpose of this article is to review recent studies that address these priorities. Studies continue to support that glaucoma patients, particularly those with advanced disease, have an increased risk of falling or unsafe driving. Risk factors, however, remain variable and include severity and location of visual field defects, contrast sensitivity, and performance on divided attention tasks. Such variability is likely because of the multifactorial nature of ambulating and driving and compensatory strategies used by patients. Falls and unsafe driving remain a serious public health issue for older adults with glaucoma. Ambulation and driving are complex tasks and there is no consensus yet, regarding the best methods for risk stratification and targeted interventions to increase safety. Therefore, comprehensive and individualized assessments are recommended to most effectively evaluate a patient's risk for falling or unsafe driving.

Risk Level Based Management System: a control banding model for occupational health and safety risk management in a highly regulated environment

Energy Technology Data Exchange (ETDEWEB)

Zalk, D; Kamerzell, R; Paik, S; Kapp, J; Harrington, D; Swuste, P

2009-05-27

The Risk Level Based Management System (RLBMS) is an occupational risk management (ORM) model that focuses occupational safety, hygeiene, and health (OSHH) resources on the highest risk procedures at work. This article demonstrates the model's simplicity through an implementation within a heavily regulated research institution. The model utilizes control banding strategies with a stratification of four risk levels (RLs) for many commonly performed maintenance and support activities, characterizing risk consistently for comparable tasks. RLBMS creates an auditable tracking of activities, maximizes OSHH professional field time, and standardizes documentation and control commensurate to a given task's RL. Validation of RLs and their exposure control effectiveness is collected in a traditional quantitative collection regime for regulatory auditing. However, qualitative risk assessment methods are also used within this validation process. Participatory approaches are used throughout the RLBMS process. Workers are involved in all phases of building, maintaining, and improving this model. This work participation also improves the implementation of established controls.

Risk management strategies by Australian farmers: two case studies

OpenAIRE

Nguyen, Nam C.; Wegener, Malcolm K.; Russell, Iean W.; Cameron, Donald; Coventry, David; Cooper, Ian M.

2007-01-01

Australian farmers operate in one of the most risky farming environments in the world. They have to cope with numerous sources of risk including weather uncertainty, variable market prices, and institutional changes in their business management. This paper reports results from two case studies undertaken to examine the issues of farming risks and risk management strategies in Australia. The first case study found that unpredictable weather, financial risk, marketing risk, and personal risk we...

Similarity rules of thermal stratification phenomena for water and sodium

International Nuclear Information System (INIS)

Ohtsuka, M.; Ikeda, T.; Yamakawa, M.; Shibata, Y.; Moriya, S.; Ushijima, S.; Fujimoto, K.

1988-01-01

Similarity rules for thermal stratification phenomena were studied using sodium and water experiments with scaled cylindrical vessels. The vessel dimensions were identical to focus on the effect of differences in fluid properties upon the phenomena. Comparisons of test results between sodium and water elucidated similar and dissimilar characteristics for thermal stratification phenomena which appeared in the scaled vessels. Results were as follows: (1) The dimensionless upward velocity of the thermal stratification interface was proportional to Ri -0.74 for water and sodium during the period when the buoyancy effect was dominant. (2) Dimensionless temperature transient rate at the outlet slit decreased with Ri for sodium and remained constant for water where Ri>0.2. The applicability of the scaled test results to an actual power plant was also studied by using multi-dimensional numerical analysis which was verified by the water and sodium experiments. Water experiments could simulate liquid metal fast breeder reactor flows more accurately than sodium experiments for dimensionless temperature gradient at the thermal stratification interface and dimensionless temperature transient rate at the intermediate heat exchanger inlet

Risk-related 18F-FDG PET/CT and new diagnostic strategies in patients with solitary pulmonary nodule: the ITALIAN multicenter trial.

Science.gov (United States)

Spadafora, Marco; Pace, Leonardo; Evangelista, Laura; Mansi, Luigi; Del Prete, Francesco; Saladini, Giorgio; Miletto, Paolo; Fanti, Stefano; Del Vecchio, Silvana; Guerra, Luca; Pepe, Giovanna; Peluso, Giuseppina; Nicolai, Emanuele; Storto, Giovanni; Ferdeghini, Marco; Giordano, Alessandro; Farsad, Mohsen; Schillaci, Orazio; Gridelli, Cesare; Cuocolo, Alberto

2018-05-05

Diagnosis of solitary pulmonary nodule (SPN) is an important public health issue and 18 F-FDG PET/CT has proven to be more effective than CT alone. Pre-test risk stratification and clinical presentation of SPN could affect the diagnostic strategy. A relevant issue is whether thoracic segmental (s)-PET/CT could be implemented in patients with SPN. This retrospective multicenter study compared the results of FDG whole-body (wb)-PET/CT to those of s-PET/CT. 18 F-FDG PET/CT of 502 patients, stratified for pre-test cancer risk, were retrospectively analyzed. The thoracic part of wb-PET/CT, considered s-PET/CT, was compared to wb-PET/CT. Clinical and PET/CT variables were investigated for SPN characterization as well as for identification of patients in whom s-PET/CT could be performed. Histopathology or follow-up data were used as a reference. In the study population, 36% had malignant, 35% benign, and 29% indeterminate SPN. 18 F-FDG uptake indicative of thoracic and extra-thoracic lesions was detectable in 13% and 3% of the patients. All patients with extra-thoracic metastases (n = 13) had thoracic lymph node involvement and highest 18 F-FDG uptake at level of SPN (negative predictive value 100%). Compared to wb-PET/CT, s-PET/CT could save about 2/3 of 18 F-FDG dose, radiation exposure or scan-time, without affecting the clinical impact of PET/CT. Pre-test probability of malignancy can guide the diagnostic strategy of 18 FDG-PET/CT in patients with SPN. In subjects with low-intermediate pretest probability s-PET/CT imaging might be planned in advance, while in those at high risk and with thoracic lymph node involvement a wb-PET/CT is necessary.

Reassessment of Ambulatory Blood Pressure Improves Renal Risk Stratification in Nondialysis Chronic Kidney Disease: Long-Term Cohort Study.

Science.gov (United States)

Minutolo, Roberto; Gabbai, Francis B; Chiodini, Paolo; Garofalo, Carlo; Stanzione, Giovanna; Liberti, Maria Elena; Pacilio, Mario; Borrelli, Silvio; Provenzano, Michele; Conte, Giuseppe; De Nicola, Luca

2015-09-01

In nondialysis chronic kidney disease, ambulatory blood pressure (ABP) performs better than clinic BP in predicting outcome, but whether repeated assessment of ABP further refines prognosis remains ill-defined. We recruited 182 consecutive hypertensive patients with nondialysis chronic kidney disease who underwent 2 ABPs 12 months apart to evaluate the enhancement in risk stratification provided by a second ABP obtained 1 year after baseline on the risk (hazard ratio and 95% confidence interval) of composite renal end point (death, chronic dialysis, and estimated glomerular filtration rate decline ≥40%). The difference in daytime and nighttime systolic BP between the 2 ABPs (daytime and nighttime bias) was added to a survival model including baseline ABP. Net reclassification improvement was also calculated. Age was 65.6±13.4 years; 36% had diabetes mellitus and 36% had previous cardiovascular event; estimated glomerular filtration rate was 42.2±19.6 mL/min per 1.73 m(2), and clinic BP was 145±18/80±11 mm Hg. Baseline ABP (daytime, 131±16/75±10 and nighttime, 122±18/66±10 mm Hg) and daytime/nighttime BP goals (58.2% and 43.4%) did not change at month 12. Besides baseline ABP values, bias for daytime and nighttime systolic BP linearly associated with renal outcome (1.12, 1.04-1.21 and 1.18, 1.08-1.29 for every 5-mm Hg increase, respectively). Classification of patients at risk improved when considering nighttime systolic level at second ABP (net reclassification improvement, 0.224; 95% confidence interval, 0.005-0.435). Patients with first and second ABPs above target showed greater renal risk (2.15, 1.29-3.59 and 1.71, 1.07-2.72, for daytime and nighttime, respectively). In nondialysis chronic kidney disease, reassessment of ABP at 1 year further refines renal prognosis; such reassessment should specifically be considered in patients with uncontrolled BP at baseline. © 2015 American Heart Association, Inc.

CFD modelling of hydrogen stratification in enclosures: Model validation and application to PAR performance

Energy Technology Data Exchange (ETDEWEB)

Hoyes, J.R., E-mail: james.hoyes@hsl.gsi.gov.uk; Ivings, M.J.

2016-12-15

Highlights: • The ability of CFD to predict hydrogen stratification phenomena is investigated. • Contrary to expectation, simulations on tetrahedral meshes under-predict mixing. • Simulations on structured meshes give good agreement with experimental data. • CFD model used to investigate the effects of stratification on PAR performance. • Results show stratification can have a significant effect on PAR performance. - Abstract: Computational Fluid Dynamics (CFD) models are maturing into useful tools for supporting safety analyses. This paper investigates the capabilities of CFD models for predicting hydrogen stratification in a containment vessel using data from the NEA/OECD SETH2 MISTRA experiments. Further simulations are then carried out to illustrate the qualitative effects of hydrogen stratification on the performance of Passive Autocatalytic Recombiner (PAR) units. The MISTRA experiments have well-defined initial and boundary conditions which makes them well suited for use in a validation study. Results are presented for the sensitivity to mesh resolution and mesh type. Whilst the predictions are shown to be largely insensitive to the mesh resolution they are surprisingly sensitive to the mesh type. In particular, tetrahedral meshes are found to induce small unphysical convection currents that result in molecular diffusion and turbulent mixing being under-predicted. This behaviour is not unique to the CFD model used here (ANSYS CFX) and furthermore, it may affect simulations run on other non-aligned meshes (meshes that are not aligned perpendicular to gravity), including non-aligned structured meshes. Following existing best practice guidelines can help to identify potential unphysical predictions, but as an additional precaution consideration should be given to using gravity-aligned meshes for modelling stratified flows. CFD simulations of hydrogen recombination in the Becker Technologies THAI facility are presented with high and low PAR positions

An Assessment of risk response strategies practiced in software projects

Directory of Open Access Journals (Sweden)

Vanita Bhoola

2014-11-01

Full Text Available Risk management and success in projects are highly intertwined – better approaches to project risk management tend to increase chances of project success in terms of achieving scope & quality, schedule and cost targets. The process of responding to risk factors during a project’s life cycle is a crucial aspect of risk management referred to as risk response strategies, in this paper. The current research explores the status of risk response strategies applied in the software development projects in India. India provides a young IT-savvy English-speaking population, which is also cost effective. Other than the workforce, the environment for implementation of software projects in India is different from the matured economies. Risk management process is a commonly discussed theme, though its implementation in practice has a huge scope for improvement in India. The paper talks about four fundamental treatments to risk response – Avoidance, Transference, Mitigation and Acceptance (ATMA. From a primary data of 302 project managers, the paper attempts to address the risk response factors that lead to successful achievement of project scope & quality, schedule and cost targets, by using a series of regressions followed with Seemingly Unrelated Regression Equations (SURE modelling. Mitigation emerged as the most significant risk response strategy to achieve project targets. Acceptance, transference, and avoidance of risk were mostly manifested in the forms of transparency in communication across stakeholders, careful study of the nature of risks and close coordination between project team, customers/end-users and top management.

TP53 mutational status is a potential marker for risk stratification in Wilms tumour with diffuse anaplasia.

Directory of Open Access Journals (Sweden)

Mariana Maschietto

Full Text Available The presence of diffuse anaplasia in Wilms tumours (DAWT is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information.We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n = 32 and gene expression (n = 36 arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling.From the 40 cases, 22 (55% had TP53 mutations (2 detected only after deep-sequencing, 20 of which also had 17p loss (91%; 18 (45% cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n = 25 had an increased risk of recurrence as a first event (p = 0.03, hazard ratio (HR, 3.89; 95% confidence interval (CI, 1.26-16.0 and death (p = 0.04, HR, 4.95; 95% CI, 1.36-31.7 compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p = 0.03. These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes.This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker.

TP53 mutational status is a potential marker for risk stratification in Wilms tumour with diffuse anaplasia.

Science.gov (United States)

Maschietto, Mariana; Williams, Richard D; Chagtai, Tasnim; Popov, Sergey D; Sebire, Neil J; Vujanic, Gordan; Perlman, Elizabeth; Anderson, James R; Grundy, Paul; Dome, Jeffrey S; Pritchard-Jones, Kathy

2014-01-01

The presence of diffuse anaplasia in Wilms tumours (DAWT) is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information. We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n = 32) and gene expression (n = 36) arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling. From the 40 cases, 22 (55%) had TP53 mutations (2 detected only after deep-sequencing), 20 of which also had 17p loss (91%); 18 (45%) cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n = 25) had an increased risk of recurrence as a first event (p = 0.03, hazard ratio (HR), 3.89; 95% confidence interval (CI), 1.26-16.0) and death (p = 0.04, HR, 4.95; 95% CI, 1.36-31.7) compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p = 0.03). These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes. This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker.

Concepts of investment risks and strategies in electricity generation

International Nuclear Information System (INIS)

De Joode, J.; Boots, M.G.

2005-06-01

This report deals with the specific investment risks in electricity generation and discusses the problems associated with energy investments in general and focus on the additional or changing risks resulting from electricity market liberalisation. The focus is on (1) risks under the control of the electricity company, and on (2) market risks, such as the risk of price changes. Ultimately, some of the approaches and strategies that enable electricity producers to counter or mitigate these risks are discussed

Risk stratification after paracetamol overdose using mechanistic biomarkers: results from two prospective cohort studies.

Science.gov (United States)

Dear, James W; Clarke, Joanna I; Francis, Ben; Allen, Lowri; Wraight, Jonathan; Shen, Jasmine; Dargan, Paul I; Wood, David; Cooper, Jamie; Thomas, Simon H L; Jorgensen, Andrea L; Pirmohamed, Munir; Park, B Kevin; Antoine, Daniel J

2018-02-01

Paracetamol overdose is common but patient stratification is suboptimal. We investigated the usefulness of new biomarkers that have either enhanced liver specificity (microRNA-122 [miR-122]) or provide mechanistic insights (keratin-18 [K18], high mobility group box-1 [HMGB1], and glutamate dehydrogenase [GLDH]). The use of these biomarkers could help stratify patients for their risk of liver injury at hospital presentation. Using data from two prospective cohort studies, we assessed the potential for biomarkers to stratify patients who overdose with paracetamol. We completed two independent prospective studies: a derivation study (MAPP) in eight UK hospitals and a validation study (BIOPAR) in ten UK hospitals. Patients in both cohorts were adults (≥18 years in England, ≥16 years in Scotland), were diagnosed with paracetamol overdose, and gave written informed consent. Patients who needed intravenous acetylcysteine treatment for paracetamol overdose had circulating biomarkers measured at hospital presentation. The primary endpoint was acute liver injury indicating need for continued acetylcysteine treatment beyond the standard course (alanine aminotransferase [ALT] activity >100 U/L). Receiver operating characteristic (ROC) curves, category-free net reclassification index (cfNRI), and integrated discrimination index (IDI) were applied to assess endpoint prediction. Between June 2, 2010, and May 29, 2014, 1187 patients who required acetylcysteine treatment for paracetamol overdose were recruited (985 in the MAPP cohort; 202 in the BIOPAR cohort). In the derivation and validation cohorts, acute liver injury was predicted at hospital presentation by miR-122 (derivation cohort ROC-area under the curve [AUC] 0·97 [95% CI 0·95-0·98]), HMGB1 (0·95 [0·93-0·98]), and full-length K18 (0·95 [0·92-0·97]). Results were similar in the validation cohort (miR-122 AUC 0·97 [95% CI 0·95-0·99], HMGB1 0·98 [0·96-0·99], and full-length K18 0·93 [0·86-0·99]). A

Experiments and numerical simulations of fluctuating thermal stratification in a branch pipe

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Akira; Murase, Michio; Sasaki, Toru [Inst. of Nuclear Safety System Inc., Mihama, Fukui (Japan); Takenaka, Nobuyuki; Hamatani, Daisuke [Kobe Univ. (Japan)

2002-09-01

Many pipes branch off from the main pipe in plants. When the main flow in the main pipe is hotter than a branch pipe that branches off downward, the hot water penetrates into the branch pipe with the cavity flow that is induced by the main flow and causes thermal stratification. If the interface of the stratification fluctuates in an occluded branch pipe, thermal fatigue may occur in pipe wall. Some experiments and numerical simulations were conducted to elucidate the mechanism of this fluctuating thermal stratification. The vortex structures were observed in the experiments of straight or bent branch pipes. When the main flow was heated and the thermal stratification interface was at the elbow, a ''burst'' phenomenon occurred in the interface in connection with large heat fluctuation. The effects of pipe shape on the length of penetration were investigated in order to modify simulation conditions. The vortex structures and the fluctuating thermal stratification at elbow in the numerical simulation showed good agreement with experiments. (author)

Cardiometabolic risk in Canada: a detailed analysis and position paper by the cardiometabolic risk working group.

Science.gov (United States)

Leiter, Lawrence A; Fitchett, David H; Gilbert, Richard E; Gupta, Milan; Mancini, G B John; McFarlane, Philip A; Ross, Robert; Teoh, Hwee; Verma, Subodh; Anand, Sonia; Camelon, Kathryn; Chow, Chi-Ming; Cox, Jafna L; Després, Jean-Pierre; Genest, Jacques; Harris, Stewart B; Lau, David C W; Lewanczuk, Richard; Liu, Peter P; Lonn, Eva M; McPherson, Ruth; Poirier, Paul; Qaadri, Shafiq; Rabasa-Lhoret, Rémi; Rabkin, Simon W; Sharma, Arya M; Steele, Andrew W; Stone, James A; Tardif, Jean-Claude; Tobe, Sheldon; Ur, Ehud

2011-01-01

The concepts of "cardiometabolic risk," "metabolic syndrome," and "risk stratification" overlap and relate to the atherogenic process and development of type 2 diabetes. There is confusion about what these terms mean and how they can best be used to improve our understanding of cardiovascular disease treatment and prevention. With the objectives of clarifying these concepts and presenting practical strategies to identify and reduce cardiovascular risk in multiethnic patient populations, the Cardiometabolic Working Group reviewed the evidence related to emerging cardiovascular risk factors and Canadian guideline recommendations in order to present a detailed analysis and consolidated approach to the identification and management of cardiometabolic risk. The concepts related to cardiometabolic risk, pathophysiology, and strategies for identification and management (including health behaviours, pharmacotherapy, and surgery) in the multiethnic Canadian population are presented. "Global cardiometabolic risk" is proposed as an umbrella term for a comprehensive list of existing and emerging factors that predict cardiovascular disease and/or type 2 diabetes. Health behaviour interventions (weight loss, physical activity, diet, smoking cessation) in people identified at high cardiometabolic risk are of critical importance given the emerging crisis of obesity and the consequent epidemic of type 2 diabetes. Vascular protective measures (health behaviours for all patients and pharmacotherapy in appropriate patients) are essential to reduce cardiometabolic risk, and there is growing consensus that a multidisciplinary approach is needed to adequately address cardiometabolic risk factors. Health care professionals must also consider risk factors related to ethnicity in order to appropriately evaluate everyone in their diverse patient populations. Copyright © 2011 Elsevier Inc. All rights reserved.

The bio-optical properties of CDOM as descriptor of lake stratification.

Science.gov (United States)

Bracchini, Luca; Dattilo, Arduino Massimo; Hull, Vincent; Loiselle, Steven Arthur; Martini, Silvia; Rossi, Claudio; Santinelli, Chiara; Seritti, Alfredo

2006-11-01

Multivariate statistical techniques are used to demonstrate the fundamental role of CDOM optical properties in the description of water masses during the summer stratification of a deep lake. PC1 was linked with dissolved species and PC2 with suspended particles. In the first principal component that the role of CDOM bio-optical properties give a better description of the stratification of the Salto Lake with respect to temperature. The proposed multivariate approach can be used for the analysis of different stratified aquatic ecosystems in relation to interaction between bio-optical properties and stratification of the water body.

Experimental study on the fluid stratification mechanism in the density lock

International Nuclear Information System (INIS)

Gu Haifeng; Yan Changqi; Sun Licheng

2009-01-01

Visualized experiments were conducted on the forming process of stratification between hot and cold fluids in three tubes with different diameters. The results show that the working fluids were divided into three layers from top to bottom: convective, interfacial, and constant temperature layers. The working fluid in the convective layer always retains the property of a high rate of temperature increase. The rate of temperature increase in the interfacial layer gradually decreased from top to bottom and was less than that in the convective layer. The working fluid temperature in the constant-temperature layer remained stable. Based on the experimental study, we built a simplified theoretical model and analyzed the stratification mechanism. The results indicate the following stratification mechanism: because of the existence of the transition points in the heat transfer modes, the differences in the rates of temperature increase appear. These differences result in the appearance of fluid stratification. In addition, research on the process of stratification under different conditions tells us that the structure of the density lock influences the position of the transition point. The density lock with a structure of variable cross-sectional grids can effectively control the position of the transition points of the heat transfer modes. (author)

On the gauge orbit space stratification: a review

International Nuclear Information System (INIS)

Rudolph, G.; Schmidt, M.; Volobuev, I.P.

2002-01-01

First, we review the basic mathematical structures and results concerning the gauge orbit space stratification. This includes general properties of the gauge group action, fibre bundle structures induced by this action, basic properties of the stratification and the natural Riemannian structures of the strata. In the second part, we study the stratification for theories with gauge group SU(n) in spacetime dimension 4. We develop a general method for determining the orbit types and their partial ordering, based on the 1-1 correspondence between orbit types and holonomy-induced Howe subbundles of the underlying principal SU(n)-bundle. We show that the orbit types are classified by certain cohomology elements of spacetime satisfying two relations and that the partial ordering is characterized by a system of algebraic equations. Moreover, operations for generating direct successors and direct predecessors are formulated, which allow one to construct the set of orbit types, starting from the principal type. Finally, we discuss an application to nodal configurations in Yang-Mills-Chern-Simons theory. (author)

Integrated collector storage solar water heater: Temperature stratification

International Nuclear Information System (INIS)

Garnier, C.; Currie, J.; Muneer, T.

2009-01-01

An analysis of the temperature stratification inside an Integrated Collector Storage Solar Water Heater (ICS-SWH) was carried out. The system takes the form of a rectangular-shaped box incorporating the solar collector and storage tank into a single unit and was optimised for simulation in Scottish weather conditions. A 3-month experimental study on the ICS-SWH was undertaken in order to provide empirical data for comparison with the computed results. Using a previously developed macro model; a number of improvements were made. The initial macro model was able to generate corresponding water bulk temperature in the collector with a given hourly incident solar radiation, ambient temperature and inlet water temperature and therefore able to predict ICS-SWH performance. The new model was able to compute the bulk water temperature variation in different SWH collectors for a given aspect ratio and the water temperature along the height of the collector (temperature stratification). Computed longitudinal temperature stratification results obtained were found to be in close agreement with the experimental data.

Rotating compressible fluids under strong stratification

Czech Academy of Sciences Publication Activity Database

Feireisl, Eduard; Lu, Y.; Novotný, A.

2014-01-01

Roč. 19, October (2014), s. 11-18 ISSN 1468-1218 Keywords : rotating fluid * compressible Navier-Stokes * strong stratification Subject RIV: BA - General Mathematics Impact factor: 2.519, year: 2014 http://www.sciencedirect.com/science/article/pii/S1468121814000212#

The efficiency of asset management strategies to reduce urban flood risk.

Science.gov (United States)

ten Veldhuis, J A E; Clemens, F H L R

2011-01-01

In this study, three asset management strategies were compared with respect to their efficiency to reduce flood risk. Data from call centres at two municipalities were used to quantify urban flood risks associated with three causes of urban flooding: gully pot blockage, sewer pipe blockage and sewer overloading. The efficiency of three flood reduction strategies was assessed based on their effect on the causes contributing to flood risk. The sensitivity of the results to uncertainty in the data source, citizens' calls, was analysed through incorporation of uncertainty ranges taken from customer complaint literature. Based on the available data it could be shown that increasing gully pot blockage is the most efficient action to reduce flood risk, given data uncertainty. If differences between cause incidences are large, as in the presented case study, call data are sufficient to decide how flood risk can be most efficiently reduced. According to the results of this analysis, enlargement of sewer pipes is not an efficient strategy to reduce flood risk, because flood risk associated with sewer overloading is small compared to other failure mechanisms.

Precommitted Investment Strategy versus Time-Consistent Investment Strategy for a General Risk Model with Diffusion

Directory of Open Access Journals (Sweden)

Lidong Zhang

2014-01-01

Full Text Available We mainly study a general risk model and investigate the precommitted strategy and the time-consistent strategy under mean-variance criterion, respectively. A lagrange method is proposed to derive the precommitted investment strategy. Meanwhile from the game theoretical perspective, we find the time-consistent investment strategy by solving the extended Hamilton-Jacobi-Bellman equations. By comparing the precommitted strategy with the time-consistent strategy, we find that the company under the time-consistent strategy has to give up the better current utility in order to keep a consistent satisfaction over the whole time horizon. Furthermore, we theoretically and numerically provide the effect of the parameters on these two optimal strategies and the corresponding value functions.

Does computer-assisted detection of pulmonary emboli enhance severity assessment and risk stratification in acute pulmonary embolism?

International Nuclear Information System (INIS)

Engelke, C.; Schmidt, S.; Auer, F.; Rummeny, E.J.; Marten, K.

2010-01-01

Aim: To prospectively assess the value of computer-aided detection (CAD) for the computed tomography (CT) severity assessment of acute pulmonary embolism (PE). Materials and methods: CT angiographic scans of 58 PE-positive patients (34-89 years, mean 66 years) were analysed by four observers for PE severity using the Mastora index, and by CAD. Patients were stratified to three PE risk groups and results compared to an independent reference standard. Interobserver agreement was tested by Bland and Altman and extended kappa (Ke) statistics. Mastora index changes after CAD data review were tested by Wilcoxon signed ranks. Results: CAD detected 343 out of 1118 emboli within given arterial segments and a total of 155 out of 218 polysegmental emboli (segmental vessel-based sensitivity = 30.7%, embolus-based sensitivity = 71.2% false-positive rate = 4.1/scan). Interobserver agreement on PE severity [95% limits of agreement (LOA) = -19.7-7.5% and-5.5-3% for reader pairs 1 versus 2 and 3 versus 4, respectively was enhanced by consensus with CAD data (LOA = -6.5-5.4% and-3.7-2% for reader pairs 1 versus 2 and 3 versus 4, respectively). Simultaneously, the percentual scoring errors (PSE) were significantly decreased (PSE = 35.4 ± 31.8% and 5.1 ± 8.9% for readers1/2 and 2/3, respectively, and PSE = 27.6 ± 31% and 3.8 ± 6.2%, respectively, after CAD consensus; p ≤ 0.005). Misclassifications to PE risk groups occurred in 27.6, 24.1, 5.2, and 5.2% of patients for readers 1-4, respectively, (Ke = 0.74) and were corrected by CAD consensus in 56.3, 36, 33.3, and 33.3% of misclassified patients, respectively (Ke = 0.83; p < 0.05). Conclusion: Radiologists may benefit from consensus with CAD data that improve PE severity scores and stratification to PE risk groups.

Acoustic study of stratification region of melts in In-Se system

International Nuclear Information System (INIS)

Glazov, V.M.; Kim, S.G.; Nurova, K.B.

1989-01-01

Stratification region of melts in In-Se system was studied in detail with the use of the method of measuring ultrasound velocity. The curve, limiting the region of stratification into two liquid solutions was plotted. It is shown that the curve is characterized as symmetrical finodal

Methods to determine stratification efficiency of thermal energy storage processes–Review and theoretical comparison

DEFF Research Database (Denmark)

Haller, Michel; Cruickshank, Chynthia; Streicher, Wolfgang

2009-01-01

This paper reviews different methods that have been proposed to characterize thermal stratification in energy storages from a theoretical point of view. Specifically, this paper focuses on the methods that can be used to determine the ability of a storage to promote and maintain stratification...... during charging, storing and discharging, and represent this ability with a single numerical value in terms of a stratification efficiency for a given experiment or under given boundary conditions. Existing methods for calculating stratification efficiencies have been applied to hypothetical storage...

Mitigating Corporate Water Risk: Financial Market Tools and Supply Management Strategies

Directory of Open Access Journals (Sweden)

Wendy M. Larson

2012-10-01

Full Text Available A decision framework for business water-risk response is proposed that considers financial instruments and supply management strategies. Based on available and emergent programmes, companies in the agricultural, commodities, and energy sectors may choose to hedge against financial risks by purchasing futures contracts or insurance products. These strategies address financial impacts such as revenue protection due to scarcity and disruption of direct operations or in the supply chain, but they do not directly serve to maintain available supplies to continue production. In contrast, companies can undertake actions in the watershed to enhance supply reliability and/or they can reduce demand to mitigate risk. Intermediate strategies such as purchasing of water rights or water trading involving financial transactions change the allocation of water but do not reduce overall watershed demand or increase water supply. The financial services industry is playing an increasingly important role, by considering how water risks impact decision making on corporate growth and market valuation, corporate creditworthiness, and bond rating. Risk assessment informed by Conditional Value-at-Risk (CVaR measures is described, and the role of the financial services industry is characterised. A corporate decision framework is discussed in the context of water resources management strategies under complex uncertainties.

Investigation of the Solvis stratification inlet pipe for solar tanks

DEFF Research Database (Denmark)

Andersen, Elsa; Jordan, Ulrike; Shah, Louise Jivan

2004-01-01

Since the 1960’ties the influence of the thermal stratification in hot water tanks on the thermal performance of solar heating systems has been studied intensively. It was found, that the thermal performance of a solar heating system is increasing for increasing thermal stratification in the hot...... water tank. The temperature of the storage water heated by the solar collector loop usually varies strongly during the day. In order to reach a good thermal stratification in the tank, different types of pipes, plates, diffusers and other devices have been investigated in the past (e.g. Loehrke, 1979...... conditions. Temperature measurements were carried out and an optical method called Particle Image Velocimetry (PIV) was used to visualize the flow around the flaps....

Risk management strategy to increase the safety of workers in the nanomaterials industry

Energy Technology Data Exchange (ETDEWEB)

Ling, Min-Pei, E-mail: lingmp@mail.cmu.edu.tw [Department of Health Risk Management, China Medical University, Taichung 40402, Taiwan, ROC (China); Lin, Wei-Chao; Liu, Chia-Chyuan [Department of Cosmetic Science, Chia Nan University of Pharmacy and Science, Tainan 71710, Taiwan, ROC (China); Huang, Yi-Shiao; Chueh, Miao-Ju [Industrial Safety and Health Association of the ROC, Taipei 11670, Taiwan, ROC (China); Shih, Tung-Sheng [Institute of Occupational Safety and Health, Council of Labor Affairs, Taipei 22143, Taiwan, ROC (China)

2012-08-30

Highlights: Black-Right-Pointing-Pointer On-site assessment of nanomaterials using physiochemical and cytotoxic analysis can help identify risks for each nanomaterials manufacturing plant. Black-Right-Pointing-Pointer The risk of the nanomaterials manufacturing plants can be divided into three levels based on exposure routes (tier 1), aspect identification (tier 2), and toxicological screening (tier 3). Black-Right-Pointing-Pointer According to the different risk levels, the precautionary risk management (PRM) such as technology control, engineering control, and personal protective equipment were applied. Black-Right-Pointing-Pointer The PRM strategy can be effectively reduced workers risks for nanomaterial industries. - Abstract: In recent years, many engineered nanomaterials (NMs) have been produced, but increasing research has revealed that these may have toxicities far greater than conventional materials and cause significant adverse health effects. At present, there is insufficient data to determine the permissible concentrations of NMs in the workplace. There is also a lack of toxicity data and environmental monitoring results relating to complete health risk assessment. In view of this, we believe that workers in the NMs industry should be provided with simple and practical risk management strategy to ensure occupational health and safety. In this study, we developed a risk management strategy based on the precautionary risk management (PRM). The risk of the engineered NMs manufacturing plants can be divided into three levels based on aspect identification, solubility tests, dermal absorption, and cytotoxic analyses. The risk management strategies include aspects relating to technology control, engineering control, personal protective equipment, and monitoring of the working environment for each level. Here we report the first case in which a simple and practical risk management strategy applying in specific engineered NMs manufacturing plants. We are

Risk management strategy to increase the safety of workers in the nanomaterials industry

International Nuclear Information System (INIS)

Ling, Min-Pei; Lin, Wei-Chao; Liu, Chia-Chyuan; Huang, Yi-Shiao; Chueh, Miao-Ju; Shih, Tung-Sheng

2012-01-01

Highlights: ► On-site assessment of nanomaterials using physiochemical and cytotoxic analysis can help identify risks for each nanomaterials manufacturing plant. ► The risk of the nanomaterials manufacturing plants can be divided into three levels based on exposure routes (tier 1), aspect identification (tier 2), and toxicological screening (tier 3). ► According to the different risk levels, the precautionary risk management (PRM) such as technology control, engineering control, and personal protective equipment were applied. ► The PRM strategy can be effectively reduced workers risks for nanomaterial industries. - Abstract: In recent years, many engineered nanomaterials (NMs) have been produced, but increasing research has revealed that these may have toxicities far greater than conventional materials and cause significant adverse health effects. At present, there is insufficient data to determine the permissible concentrations of NMs in the workplace. There is also a lack of toxicity data and environmental monitoring results relating to complete health risk assessment. In view of this, we believe that workers in the NMs industry should be provided with simple and practical risk management strategy to ensure occupational health and safety. In this study, we developed a risk management strategy based on the precautionary risk management (PRM). The risk of the engineered NMs manufacturing plants can be divided into three levels based on aspect identification, solubility tests, dermal absorption, and cytotoxic analyses. The risk management strategies include aspects relating to technology control, engineering control, personal protective equipment, and monitoring of the working environment for each level. Here we report the first case in which a simple and practical risk management strategy applying in specific engineered NMs manufacturing plants. We are confident that our risk management strategy can be effectively reduced engineered NM industries risks for

Cost-effectiveness and harm-benefit analyses of risk-based screening strategies for breast cancer.

Directory of Open Access Journals (Sweden)

Ester Vilaprinyo

Full Text Available The one-size-fits-all paradigm in organized screening of breast cancer is shifting towards a personalized approach. The present study has two objectives: 1 To perform an economic evaluation and to assess the harm-benefit ratios of screening strategies that vary in their intensity and interval ages based on breast cancer risk; and 2 To estimate the gain in terms of cost and harm reductions using risk-based screening with respect to the usual practice. We used a probabilistic model and input data from Spanish population registries and screening programs, as well as from clinical studies, to estimate the benefit, harm, and costs over time of 2,624 screening strategies, uniform or risk-based. We defined four risk groups, low, moderate-low, moderate-high and high, based on breast density, family history of breast cancer and personal history of breast biopsy. The risk-based strategies were obtained combining the exam periodicity (annual, biennial, triennial and quinquennial, the starting ages (40, 45 and 50 years and the ending ages (69 and 74 years in the four risk groups. Incremental cost-effectiveness and harm-benefit ratios were used to select the optimal strategies. Compared to risk-based strategies, the uniform ones result in a much lower benefit for a specific cost. Reductions close to 10% in costs and higher than 20% in false-positive results and overdiagnosed cases were obtained for risk-based strategies. Optimal screening is characterized by quinquennial or triennial periodicities for the low or moderate risk-groups and annual periodicity for the high-risk group. Risk-based strategies can reduce harm and costs. It is necessary to develop accurate measures of individual risk and to work on how to implement risk-based screening strategies.

Strategies and criteria for risk-based configuration control

International Nuclear Information System (INIS)

Samanta, P.K.; Kim, I.S.; Vesely, W.E.

1991-01-01

A configuration, as used here, is a set of component operability or statuses that define the state of a nuclear power plant. Risk-based configuration control is the management of component configurations using a risk perspective to control risk and assure safety. If the component configurations that have high risk implications do not occur then the risk from the operation of nuclear power plants would be minimal. The control of component configurations, i.e., the management of component statuses, so that the risk from components being unavailable is minimized, becomes difficult because the status of a standby safety system component is often not apparent unless it is tested. In this paper, we discuss the strategies and criteria for risk-based configuration control in nuclear power plants. In developing these strategies and criteria, the primary objective is to obtain more direct risk control but the added benefit is the effective use of plant resources. Implementation of such approaches can result in replacement/modification of parts of Technical Specifications. Specifically, the risk impact or safety impact of a configuration depends upon four factors: (1) The configuration components which are simultaneously down (i.e., inoperable); (2) the backup components which are known to be up (i.e., operable); (3) the duration of time the configuration exists (the outage time); and (4) the frequency at which the configuration occurs. Risk-based configuration control involves managing these factors using risk analyses and risk insights. In this paper, we discuss each of the factors and illustrate how they can be controlled. The information and the tools needed in implementing configuration control are also discussed. The risk-based calculation requirements in achieving the control are also delineated. 4 refs., 4 figs., 1 tab

Temperature Stratification in a Cryogenic Fuel Tank

Data.gov (United States)

National Aeronautics and Space Administration — A reduced dynamical model describing temperature stratification effects driven by natural convection in a liquid hydrogen cryogenic fuel tank has been developed. It...

On Stratification in Changing Higher Education: The "Analysis of Status" Revisited

Science.gov (United States)

Bloch, Roland; Mitterle, Alexander

2017-01-01

This article seeks to shed light on current dynamics of stratification in changing higher education and proposes an analytical perspective to account for these dynamics based on Martin Trow's work on "the analysis of status." In research on higher education, the term "stratification" is generally understood as a metaphor that…

Optimal combined purchasing strategies for a risk-averse manufacturer under price uncertainty

Directory of Open Access Journals (Sweden)

Qiao Wu

2015-09-01

Full Text Available Purpose: The purpose of our paper is to analyze optimal purchasing strategies when a manufacturer can buy raw materials from a long-term contract supplier and a spot market under spot price uncertainty. Design/methodology/approach: This procurement model can be solved by using dynamic programming. First, we maximize the DM’s utility of the second period, obtaining the optimal contract quantity and spot quantity for the second period. Then, maximize the DM’s utility of both periods, obtaining the optimal purchasing strategy for the first period. We use a numerical method to compare the performance level of a pure spot sourcing strategy with that of a mixed strategy. Findings: Our results show that optimal purchasing strategies vary with the trend of contract prices. If the contract price falls, the total quantity purchased in period 1 will decrease in the degree of risk aversion. If the contract price increases, the total quantity purchased in period 1 will increase in the degree of risk aversion. The relationship between the optimal contract quantity and the degree of risk aversion depends on whether the expected spot price or the contract price is larger in period 2. Finally, we compare the performance levels between a combined strategy and a spot sourcing strategy. It shows that a combined strategy is optimal for a risk-averse buyer. Originality/value: It’s challenging to deal with a two-period procurement problem with risk consideration. We have obtained results of a two-period procurement problem with two sourcing options, namely contract procurement and spot purchases. Our model incorporates the buyer’s risk aversion factor and the change of contract prices, which are not addressed in early studies.

Preoperative B-type natriuretic peptide risk stratification: Do ...

African Journals Online (AJOL)

Objectives: It is unclear if there is value in measuring postoperative B-type natriuretic peptide (BNP) in patients risk-stratified using preoperative BNP. Design: Prospective observational study. Setting and subjects: Patients undergoing vascular surgery at Inkosi Albert Luthuli Hospital, Durban. Data on intraoperative risk ...

Communicating about risk: strategies for situations where public concern is high but the risk is low

Directory of Open Access Journals (Sweden)

Claire Hooker

2017-02-01

Full Text Available In this article, we summarise research that identifies best practice for communicating about hazards where the risk is low but public concern is high. We apply Peter Sandman’s ‘risk = hazard + outrage’ formulation to these risks, and review factors associated with the amplification of risk signals. We discuss the structures that determine the success of risk communication strategies, such as the capacity for early communication to ‘capture’ the dominant representation of risk issues, the importance of communicating uncertainty, and the usefulness of engaging with communities. We argue that, when facing trade-offs in probable outcomes from communication, it is always best to choose strategies that maintain or build trust, even at the cost of initial overreactions. We discuss these features of successful risk communication in relation to a range of specific examples, particularly opposition to community water fluoridation, Ebola, and routine childhood immunisation.

Performance of the 2015 International Task Force Consensus Statement Risk Stratification Algorithm for Implantable Cardioverter-Defibrillator Placement in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy.

Science.gov (United States)

Orgeron, Gabriela M; Te Riele, Anneline; Tichnell, Crystal; Wang, Weijia; Murray, Brittney; Bhonsale, Aditya; Judge, Daniel P; Kamel, Ihab R; Zimmerman, Stephan L; Tandri, Harikrishna; Calkins, Hugh; James, Cynthia A

2018-02-01

Ventricular arrhythmias are a feared complication of arrhythmogenic right ventricular dysplasia/cardiomyopathy. In 2015, an International Task Force Consensus Statement proposed a risk stratification algorithm for implantable cardioverter-defibrillator placement in arrhythmogenic right ventricular dysplasia/cardiomyopathy. To evaluate performance of the algorithm, 365 arrhythmogenic right ventricular dysplasia/cardiomyopathy patients were classified as having a Class I, IIa, IIb, or III indication per the algorithm at baseline. Survival free from sustained ventricular arrhythmia (VT/VF) in follow-up was the primary outcome. Incidence of ventricular fibrillation/flutter cycle length the algorithm appropriately differentiated risk of VT/VF, incidence of VT/VF was underestimated (observed versus expected: 29.6 [95% confidence interval, 25.2-34.0] versus >10%/year Class I; 15.5 [confidence interval 11.1-21.6] versus 1% to 10%/year Class IIa). In addition, the algorithm did not differentiate survival free from ventricular fibrillation/flutter between Class I and IIa patients ( P =0.97) or for VT/VF in Class I and IIa primary prevention patients ( P =0.22). Adding Holter results (the algorithm differentiates arrhythmic risk well overall, it did not distinguish ventricular fibrillation/flutter risks of patients with Class I and IIa implantable cardioverter-defibrillator indications. Limited differentiation was seen for primary prevention cases. As these are vital uncertainties in clinical decision-making, refinements to the algorithm are suggested prior to implementation. © 2018 American Heart Association, Inc.

Propagation of 3D internal gravity wave beams in a slowly varying stratification

Science.gov (United States)

Fan, Boyu; Akylas, T. R.

2017-11-01

The time-mean flows induced by internal gravity wave beams (IGWB) with 3D variations have been shown to have dramatic implications for long-term IGWB dynamics. While uniform stratifications are convenient both theoretically and in the laboratory, stratifications in the ocean can vary by more than an order of magnitude over the ocean depth. Here, in view of this fact, we study the propagation of a 3D IGWB in a slowly varying stratification. We assume that the stratification varies slowly relative to the local variations in the wave profile. In the 2D case, the IGWB bends in response to the changing stratification, but nonlinear effects are minor even in the finite amplitude regime. For a 3D IGWB, in addition to bending, we find that nonlinearity results in the transfer of energy from waves to a large-scale time-mean flow associated with the mean potential vorticity, similar to IGWB behavior in a uniform stratification. In a weakly nonlinear setting, we derive coupled evolution equations that govern this process. We also use these equations to determine the stability properties of 2D IGWB to 3D perturbations. These findings indicate that 3D effects may be relevant and possibly fundamental to IGWB dynamics in nature. Supported by NSF Grant DMS-1512925.

Distribution of Cervical Lymph Node Metastases From Squamous Cell Carcinoma of the Oropharynx in the Era of Risk Stratification Using Human Papillomavirus and Smoking Status.

Science.gov (United States)

Amsbaugh, Mark J; Yusuf, Mehran; Cash, Elizabeth; Silverman, Craig; Wilson, Elizabeth; Bumpous, Jeffrey; Potts, Kevin; Perez, Cesar; Bert, Robert; Redman, Rebecca; Dunlap, Neal

2016-10-01

To investigate the factors contributing to the clinical presentation of oropharyngeal squamous cell carcinoma (OPSCC) in the era of risk stratification using human papilloma virus (HPV) and smoking status. All patients with OPSCC presenting to our institutional multidisciplinary clinic from January 2009 to June 2015 were reviewed from a prospective database. The patients were grouped as being at low risk, intermediate risk, and high risk in the manner described by Ang et al. Variance in clinical presentation was examined using χ(2), Kruskal-Wallis, Mann-Whitney, and logistic regression analyses. The rates of HPV/p16 positivity (Phigh-risk patients presented with tumor stage T4 at a much higher than expected frequency (P=.003). Patients with BOT primary tumors who were never-smokers were less likely to have clinically involved ipsilateral neck disease than were former smokers (odds ratio 1.8; P=.038). The distribution of cervical lymph node metastases was not associated with HPV/p16 positivity, risk group, or subsite. When these data were compared with those in historical series, no significant differences were seen in the patterns of cervical lymph node metastases for patients with OPSCC. For patients with OPSCC differences in HPV status, smoking history and anatomic subsite were associated with differences in clinical presentation but not with distribution of cervical lymph node metastases. Historical series describing the patterns of cervical lymph node metastases in patients with OPSCC remain clinically relevant. Copyright © 2016 Elsevier Inc. All rights reserved.

Predictive value of routine point-of-care cardiac troponin T measurement for prehospital diagnosis and risk-stratification in patients with suspected acute myocardial infarction

DEFF Research Database (Denmark)

Rasmussen, Martin B; Stengaard, Carsten; Sørensen, Jacob T

2017-01-01

-of-care cardiac troponin T measurements (11.0%) had a value ≥50 ng/l, including 966 with acute myocardial infarction (sensitivity: 44.2%, specificity: 92.8%). Patients presenting with a prehospital point-of-care cardiac troponin T value ≥50 ng/l had a one-year mortality of 24% compared with 4.8% in those...... with values analysis: point-of-care cardiac troponin T≥50 ng/l (hazard ratio 2.10, 95% confidence interval: 1.90-2.33), congestive heart failure (hazard ratio 1.93, 95% confidence interval: 1......OBJECTIVE: The purpose of this study was to determine the predictive value of routine prehospital point-of-care cardiac troponin T measurement for diagnosis and risk stratification of patients with suspected acute myocardial infarction. METHODS AND RESULTS: All prehospital emergency medical service...

Thermal stratification in storage tanks of integrated collector storage solar water heaters

International Nuclear Information System (INIS)

Oshchepkov, M.Y.; Frid, S.E.

2015-01-01

To determine the influence of the shape of the tank, the installation angle, and the magnitude of the absorbed heat flux on thermal stratification in integrated collector-storage solar water heaters, numerical simulation of thermal convection in tanks of different shapes and same volume was carried out. Idealized two-dimensional models were studied; auto model stratification profiles were obtained at the constant heat flux. The shape of the tank, the pattern of the heat flux dynamics, the adiabatic mixing on the circulation rate and the degree of stratification were shown to have significant influence. (authors)

Market transition, educational disparities, and family strategies in rural China: new evidence on gender stratification and development.

Science.gov (United States)

Hannum, Emily

2005-05-01

Two theoretical perspectives have dominated debates about the impact of development on gender stratification: modernization theory, which argues that gender inequalities decline with economic growth, and the "women in development" perspective, which argues that development may initially widen gender gaps. Analyzing cross-sectional surveys and time-series data from China, this article indicates the relevance of both perspectives: while girls' educational opportunities were clearly more responsive than boys' to better household economic circumstances, the era of market transition in the late 1970s and early 1980s failed to accelerate and, in fact, may have temporarily slowed progress toward gender equity.

An Improved Model of Cryogenic Propellant Stratification in a Rotating, Reduced Gravity Environment

Science.gov (United States)

Oliveira, Justin; Kirk, Daniel R.; Schallhorn, Paul A.; Piquero, Jorge L.; Campbell, Mike; Chase, Sukhdeep

2007-01-01

This paper builds on a series of analytical literature models used to predict thermal stratification within rocket propellant tanks. The primary contribution to the literature is to add the effect of tank rotation and to demonstrate the influence of rotation on stratification times and temperatures. This work also looks levels of thermal stratification for generic propellant tanks (cylindrical shapes) over a parametric range of upper-stage coast times, heating levels, rotation rates, and gravity levels.

Application of adversarial risk analysis model in pricing strategies with remanufacturing

Directory of Open Access Journals (Sweden)

Liurui Deng

2015-01-01

Full Text Available Purpose: Purpose: This paper mainly focus on the application of adversarial risk analysis (ARA in pricing strategy with remanufacturing. We hope to obtain more realistic results than classical model. Moreover, we also wish that our research improve the development of ARA in pricing strategy of manufacturing or remanufacturing. Approach: In order to gain more actual research, combining adversarial risk analysis, we explore the pricing strategy with remanufacturing based on Stackelberg model. Especially, we build OEM’s 1-order ARA model and further study on manufacturers and remanufacturers’ pricing strategy. Findings: We find the OEM’s 1-order ARA model for the OEM’s product cost C. Besides, we get according manufacturers and remanufacturers’ pricing strategies. Besides, the pricing strategies based on 1-order ARA model have advantage over than the classical model regardless of OEMs and remanufacturers. Research implications: The research on application of ARA imply that we can get more actual results with this kind of modern risk analysis method and ARA can be extensively in pricing strategies of supply chain. Value: Our research improves the application of ARA in remanufacturing industry. Meanwhile, inspired by this analysis, we can also create different ARA models for different parameters. Furthermore, some results and analysis methods can be applied to other pricing strategies of supply chain.

Risk management: a proposal for communication strategies

Directory of Open Access Journals (Sweden)

Michele Fontana

2012-07-01

Full Text Available Disasters related to natural hazards have increased in the last few decades. This increment makes it necessary to develop non-structural risk prevention and mitigation measures to improve people’s safety. An effective non-structural measure that can improve the preparedness of the population is a locally adapted communication campaign that is focused on natural hazards. We have developed a hypothetical communication campaign for a specific area in the north of Italy, in which hydro-geological risk is of considerable importance. The content of the campaign is defined by the combination of the requirements of the law with the results of a survey conducted in the study area. The aim of the survey is to evaluate the level of risk perception among the residents, and their attitudes towards prevention activities. The operative procedure of the campaign is modeled on advertising strategies. The campaign is designed to reach each family, and it is aimed at affecting people’s everyday life through a horizontal communication strategy that involves flyers, billboards, umbrellas and a website. The use of umbrellas as a medium for the campaign is the key. People mostly use umbrellas when it rains. Rain is linked with hydrogeological risk. As the content of the campaign is printed on the umbrellas, each time people use these umbrellas, they remember the campaign. The campaign is integrated into a broader communication program that includes meetings with stakeholders, activities in schools, and public conferences. The final goal is to foster the creation of a shared knowledge about risk in the whole population.

Risk management strategies utilized by small scale poultry farmers ...

African Journals Online (AJOL)

Birds can only tolerate narrow temperature changes; therefore, poultry flocks are vulnerable to climate induced risk. This study investigated risk management strategies utilized by small scale poultry farmers in Oyo state. A total of 118 respondents were sampled using multi stage sampling procedure. Interview schedule was ...

Characteristics of multiple auroral inverted-V structures and the problem of magnetospheric plasma stratification

International Nuclear Information System (INIS)

Antonova, E.E.; Stepanova, M.V.; Teltzov, M.V.; Tverskoy, B.A.

1993-01-01

The concept of hot stratification of magnetospheric plasma is presented. The stratification mechanism is based on the assumption that in the center of plasma sheet the pressure is approximately isotropic and under steady state conditions the gradient and curvature drift currents play the principal role. The number of formed structures is determined by the parameter of stratification. 7 figs., 2 tabs

Thermal stratification built up in hot water tank with different inlet stratifiers

DEFF Research Database (Denmark)

Dragsted, Janne; Furbo, Simon; Dannemand, Mark

2017-01-01

Thermal stratification in a water storage tank can strongly increase the thermal performance of solar heating systems. Thermal stratification can be built up in a storage tank during charge, if the heated water enters through an inlet stratifier. Experiments with a test tank have been carried out...... in order to elucidate how well thermal stratification is established in the tank with differently designed inlet stratifiers under different controlled laboratory conditions. The investigated inlet stratifiers are from Solvis GmbH & Co KG and EyeCular Technologies ApS. The inlet stratifier from Solvis Gmb...... for Solvis GmbH & Co KG had a better performance at 4 l/min. In the intermediate charge test the stratifier from EyeCular Technologies ApS had a better performance in terms of maintaining the thermal stratification in the storage tank while charging with a relative low temperature. [All rights reserved...

Risk perception influences athletic pacing strategy.

Science.gov (United States)

Micklewright, Dominic; Parry, David; Robinson, Tracy; Deacon, Greg; Renfree, Andrew; St Clair Gibson, Alan; Matthews, William J

2015-05-01

The objective of this study is to examine risk taking and risk perception associations with perceived exertion, pacing, and performance in athletes. Two experiments were conducted in which risk perception was assessed using the domain-specific risk taking (DOSPERT) scale in 20 novice cyclists (experiment 1) and 32 experienced ultramarathon runners (experiment 2). In experiment 1, participants predicted their pace and then performed a 5-km maximum effort cycling time trial on a calibrated Kingcycle mounted bicycle. Split times and perceived exertion were recorded every kilometer. In experiment 2, each participant predicted their split times before running a 100-km ultramarathon. Split times and perceived exertion were recorded at seven checkpoints. In both experiments, higher and lower risk perception groups were created using median split of DOSPERT scores. In experiment 1, pace during the first kilometer was faster among lower risk perceivers compared with higher risk perceivers (t(18) = 2.0, P = 0.03) and faster among higher risk takers compared with lower risk takers (t(18) = 2.2, P = 0.02). Actual pace was slower than predicted pace during the first kilometer in both the higher risk perceivers (t(9) = -4.2, P = 0.001) and lower risk perceivers (t(9) = -1.8, P = 0.049). In experiment 2, pace during the first 36 km was faster among lower risk perceivers compared with higher risk perceivers (t(16) = 2.0, P = 0.03). Irrespective of risk perception group, actual pace was slower than predicted pace during the first 18 km (t(16) = 8.9, P risk perception groups. Initial pace is associated with an individual's perception of risk, with low perceptions of risk being associated with a faster starting pace. Large differences between predicted and actual pace suggest that the performance template lacks accuracy, perhaps indicating greater reliance on momentary pacing decisions rather than preplanned strategy.

Glacial ocean circulation and stratification explained by reduced atmospheric temperature.

Science.gov (United States)

Jansen, Malte F

2017-01-03

Earth's climate has undergone dramatic shifts between glacial and interglacial time periods, with high-latitude temperature changes on the order of 5-10 °C. These climatic shifts have been associated with major rearrangements in the deep ocean circulation and stratification, which have likely played an important role in the observed atmospheric carbon dioxide swings by affecting the partitioning of carbon between the atmosphere and the ocean. The mechanisms by which the deep ocean circulation changed, however, are still unclear and represent a major challenge to our understanding of glacial climates. This study shows that various inferred changes in the deep ocean circulation and stratification between glacial and interglacial climates can be interpreted as a direct consequence of atmospheric temperature differences. Colder atmospheric temperatures lead to increased sea ice cover and formation rate around Antarctica. The associated enhanced brine rejection leads to a strongly increased deep ocean stratification, consistent with high abyssal salinities inferred for the last glacial maximum. The increased stratification goes together with a weakening and shoaling of the interhemispheric overturning circulation, again consistent with proxy evidence for the last glacial. The shallower interhemispheric overturning circulation makes room for slowly moving water of Antarctic origin, which explains the observed middepth radiocarbon age maximum and may play an important role in ocean carbon storage.

At-admission risk stratification for in-hospital life-threatening ventricular arrhythmias and death in non-ST elevation myocardial infarction patients.

Science.gov (United States)

Zorzi, Alessandro; Turri, Riccardo; Zilio, Filippo; Spadotto, Veronica; Baritussio, Anna; Peruzza, Francesco; Gasparetto, Nicola; Marra, Martina Perazzolo; Cacciavillani, Luisa; Marzari, Armando; Tarantini, Giuseppe; Iliceto, Sabino; Corrado, Domenico

2014-12-01

Identification of patients with non-ST elevation acute myocardial infarction (NSTEMI) at higher risk of in-hospital life-threatening ventricular arrhythmias (LT-VA) and death is crucial for determining appropriate levels of care/monitoring during hospitalisation. We assessed predictors of in-hospital LT-VA and all-cause mortality in a consecutive series of NSTEMI patients. We prospectively studied 1325 consecutive patients (69.7% males, median age 70 (61-79) years) presenting with NSTEMI and undergoing continuous electrocardiographic monitoring. The primary study end-point was the occurrence of spontaneous (unrelated to coronary interventions) in-hospital LT-VA, including sustained ventricular tachycardia and ventricular fibrillation; the secondary end-point was in-hospital mortality from all causes. Of 1325 patients, 21 (1.5%) experienced LT-VA and 62 (4.7%) died from either arrhythmias (n=1) or other causes (n=61). Seven of the 20 patients who survived LT-VA subsequently died of heart failure. Independent predictors of in-hospital LT-VA were the Global Registry of Acute Coronary Events (GRACE) score >140 (odds ratio (OR)=7.5; 95% confidence interval (CI) 1.7-33.3; p=0.008) and left ventricular ejection fraction (LV-EF)140 (OR=14.6; 95% CI 3.4-62) and LV-EF 140 and LV-EF<35%, while it was respectively 0.2% and 0% among the 627 (47.3%) with GRACE score ≤140 and LV-EF ≥35%. Simple risk stratification at admission based on GRACE score and echocardiographic LV-EF allows early identification of NSTEMI patients at higher risk of both in-hospital LT-VA and all-cause mortality. © The European Society of Cardiology 2014.

Acute Kidney Injury Risk Assessment: Differences and Similarities Between Resource-Limited and Resource-Rich Countries

Directory of Open Access Journals (Sweden)

Kianoush Kashani

2017-07-01

Full Text Available The incidence of acute kidney injury (AKI among acutely ill patients is reportedly very high and has vexing consequences on patient outcomes and health care systems. The risks and impact of AKI differ between developed and developing countries. Among developing countries, AKI occurs in young individuals with no or limited comorbidities, and is usually due to environmental causes, including infectious diseases. Although several risk factors have been identified for AKI in different settings, there is limited information on how risk assessment can be used at population and patient levels to improve care in patients with AKI, particularly in developing countries where significant health disparities may exist. The Acute Disease Quality Initiative consensus conference work group addressed the issue of identifying risk factors for AKI and provided recommendations for developing individualized risk stratification strategies to improve care. We proposed a 5-dimension, evidence-based categorization of AKI risk that allows clinicians and investigators to study, define, and implement individualized risk assessment tools for the region or country where they practice. These dimensions include environmental, socioeconomic and cultural factors, processes of care, exposures, and the inherent risks of AKI. We provide examples of these risks and describe approaches for risk assessments in the developing world. We anticipate that these recommendations will be useful for health care providers to plan and execute interventions to limit the impact of AKI on society and each individual patient. Using a modified Delphi process, this group reached consensus regarding several aspects of AKI risk stratification.

Economic Stratification Differentiates Home Gardens in the Maya Village of Pomuch, Mexico

NARCIS (Netherlands)

Poot-Pool, W.S.; Wal, van der J.C.; Flores-Guido, S.; Pat-Fernández, J.M.; Esparza-Olguín, L.

2012-01-01

Economic Stratification Differentiates Home Gardens in the Maya Village of Pomuch, Mexico. In this paper, we analyze if economic stratification of peasant families in a Maya village in the Yucatán Peninsula of Mexico influences species composition and structure of home gardens. Our general

From institutional segmentation to market fragmentation: Institutional transformation and the shifting stratification order in urban China.

Science.gov (United States)

Zhao, Wei; Zhou, Xueguang

2017-03-01

Focusing on the changing roles of organizations, this study develops an institutional framework to examine the shifting stratification order since the mid-1990s in urban China. We argue that, after the mid-1990s, the Chinese state led a dual process of institutional transformation. On the one hand, the state dismantled the socialist redistributive system and broke down institutional segmentation based on organizational ownership and bureaucratic rank. On the other hand, the state developed different markets with various paces and strategies, resulting in fragmented market environments. In this context, reformed organizations interacted with heterogeneous market conditions to exert different impacts on multiple dimensions of social inequality. We draw empirical evidence from two national survey data collected in 1994 and 2003 during a critical period. Our findings show that the foundation of the stratification order has shifted from institutional segmentation to market fragmentation in urban China. This study calls for substantive institutional analysis to better understand the intricate landscape of social inequality in transitional economies. Copyright © 2016 Elsevier Inc. All rights reserved.

Analysis of ABC (D) stratification for screening patients with gastric cancer.

Science.gov (United States)

Kudo, Tomohiro; Kakizaki, Satoru; Sohara, Naondo; Onozato, Yasuhiro; Okamura, Shinichi; Inui, Yoshikatsu; Mori, Masatomo

2011-11-21

To evaluate the value of ABC (D) stratification [combination of serum pepsinogen and Helicobacter pylori (H. pylori) antibody] of patients with gastric cancer. Ninety-five consecutive patients with gastric cancer were enrolled into the study. The serum pepsinogen I (PG I)/pepsinogen II (PG II) and H. pylori antibody levels were measured. Patients were classified into five groups of ABC (D) stratification according to their serological status. Endoscopic findings of atrophic gastritis and histological differentiation were also analyzed in relation to the ABC (D) stratification. The mean patient age was (67.9 ± 8.9) years. Three patients (3.2%) were classified into group A, 7 patients (7.4%) into group A', 27 patients (28.4%) into group B, 54 patients (56.8%) into group C, and 4 patients (4.2%) into group D, respectively. There were only three cases in group A when the patients taking acid proton pump inhibitors and those who had undergone eradication therapy for H. pylori (group A') were excluded. These three cases had mucosal atrophy in the grey zone according to the diagnostic manual of ABC (D) stratification. Histologically, the mean age of the patients with well differentiated adenocarcinoma was significantly higher than that of the patients with poorly differentiated adenocarcinoma (P ABC (D) stratification is a good method for screening patients with gastric cancers. Endoscopy is needed for grey zone cases to check the extent of mucosal atrophy.

3 for the Price of 1: Teaching Chest Pain Risk Stratification in a Multidisciplinary, Problem-based Learning Workshop

Directory of Open Access Journals (Sweden)

Cynthia Burns

2018-03-01

Full Text Available Introduction: Chest pain is a common chief complaint among patients presenting to health systems and often leads to complex and intensive evaluations. While these patients are often cared for by a multidisciplinary team (primary care, emergency medicine, and cardiology, medical students usually learn about the care of these patients in a fragmented, single-specialty paradigm. The present and future care of patients with chest pain is multidisciplinary, and the education of medical students on the subject should be as well. Our objective was to evaluate the effectiveness of a multidisciplinary, problem-based learning workshop to teach third-year medical students about risk assessment for patients presenting with chest pain, specifically focusing on acute coronary syndromes. Methods: To create an educational experience consistent with multidisciplinary team-based care, we designed a multidisciplinary, problem-based learning workshop to provide medical students with an understanding of how patients with chest pain are cared for in a systems-based manner to improve outcomes. Participants included third-year medical students (n=219 at a single, tertiary care, academic medical center. Knowledge acquisition was tested in a pre-/post-retention test study design. Results: Following the workshop, students achieved a 19.7% (95% confidence interval [CI] [17.3–22.2%] absolute increase in scores on post-testing as compared to pre-testing. In addition, students maintained an 11.1% (95% CI [7.2–15.0%] increase on a retention test vs. the pre-test. Conclusion: A multidisciplinary, problem-based learning workshop is an effective method of producing lasting gains in student knowledge about chest pain risk stratification.

Inhibitor Risk Stratification and Individualized Treatment in Patients With Nonsevere Hemophilia A: A Single-Institution Practice Audit.

Science.gov (United States)

Sun, Haowei Linda; Chan, Stella; Yenson, Paul; Jackson, Shannon

2018-03-01

Inhibitor risk in nonsevere hemophilia A increases with cumulative factor VIII (FVIII) exposure days and high-risk mutations. A standardized approach to minimize inhibitor risk is warranted. Following establishment of a systematic approach to reduce inhibitor risk in nonsevere hemophilia, we evaluated the uptake of these strategies into clinical practice. All adult males with nonsevere hemophilia A followed by British Columbia Adult Hemophilia Program from 2004 to 2016 were included in this retrospective audit. Quality-of-care indicators on inhibitor prevention were examined. Of 108 patients, 18 patients had high-risk FVIII mutations for inhibitor development. Rates of FVIII genotyping and 1-deamino-8-d-arginine-vasopressin (DDAVP) testing in mild patients without contraindications were both over 90%, although DDAVP was used for surgical prophylaxis in only 70% of procedures. Inhibitor testing and clinic visits occurred at a median interval of 22 months. Over 80% of patients with high-risk mutations had documentation and education on their inhibitor risk. Our practice audit demonstrated a high level of recognition and patient education of individual inhibitor risk. Impact of our standardized approach on the incidence of inhibitor development is yet to be determined.

Thermal stratification in sodium. Proceedings of an International Atomic Energy Agency specialists' meeting

Energy Technology Data Exchange (ETDEWEB)

Costa, J [Commissariat a l' Energie Atomique, Centre d' Etudes Nucleaires de Grenoble, Grenoble (France)

1983-07-01

The purpose of the meeting was to discuss and exchange views on thermal stratification existing in sodium of the main vessel, secondary circuits and large components of LMFBRs under various operating conditions. The meeting was divided into four sessions: national position presentations; fundamental studies on theory and application of stratification problems, numerical and experimental investigations applied to stratified flow phenomena; computer codes for evaluation of thermal stratification; applied studies covering the computer codes and experimental studies for prediction of temperature velocity field.

Thermal stratification in sodium. Proceedings of an International Atomic Energy Agency specialists' meeting

International Nuclear Information System (INIS)

Costa, J.

1983-07-01

The purpose of the meeting was to discuss and exchange views on thermal stratification existing in sodium of the main vessel, secondary circuits and large components of LMFBRs under various operating conditions. The meeting was divided into four sessions: national position presentations; fundamental studies on theory and application of stratification problems, numerical and experimental investigations applied to stratified flow phenomena; computer codes for evaluation of thermal stratification; applied studies covering the computer codes and experimental studies for prediction of temperature velocity field

Structural evaluation method study and procedure development for pressurizer surge line subjected to thermal stratification phenomenon

International Nuclear Information System (INIS)

Zhang Yixiong; Yu Xiaofei; Ai Honglei

2014-01-01

Thermal stratification phenomenon of pressurizer surge line can lead potential threaten to plant safety. Base on the mechanism of thermal stratification occurrence, Fr number is used to judge whether the stratification occurs or not. Also the method of calculating heat transfer coefficient is investigated. Theoretically the 3-dimension thermal stress induced by thermal stratification is decoupled to 1-dimension global stress and 2-dimension local stress, and the complex 3-dimension problem is simplified into a combination of 1-dimension and 2-dimension to compute the stress. Comply with criterion RCC-M, the complete structure integrity evaluation is accomplished after combining the stress produced by thermal stratification and the stresses produced by the other loadings. In order to match the above combined analysis method, Code SYSTUS and ROCOCO are developed. By means of aforesaid evaluation method and corresponding analysis program, surge line thermal stratification of Qinshan Phase II Extension project is investigated in this paper. And the results show that structural integrity of the pressurizer surge line affected by thermal stratification still satisfies criterion RCC-M. (authors)

A Personalized Risk Stratification Platform for Population Lifetime Healthcare.

Science.gov (United States)

Daowd, Ali; Abidi, Samina Raza; Abusharekh, Ashraf; Abidi, Syed Sibte Raza

2018-01-01

Chronic diseases are the leading cause of death worldwide. It is well understood that if modifiable risk factors are targeted, most chronic diseases can be prevented. Lifetime health is an emerging health paradigm that aims to assist individuals to achieve desired health targets, and avoid harmful lifecycle choices to mitigate the risk of chronic diseases. Early risk identification is central to lifetime health. In this paper, we present a digital health-based platform (PRISM) that leverages artificial intelligence, data visualization and mobile health technologies to empower citizens to self-assess, self-monitor and self-manage their overall risk of major chronic diseases and pursue personalized chronic disease prevention programs. PRISM offers risk assessment tools for 5 chronic conditions, 2 psychiatric disorders and 8 different cancers.

Mean platelet volume as a risk stratification tool in the Emergency Department for evaluating patients with ischaemic stroke and TIA

International Nuclear Information System (INIS)

Dogan, N.O.; Karakurt, K.

2013-01-01

Objective: To investigate the variations of mean platelet volume in patients with ischaemic cerebrovascular complaints, and to find out its diagnostic utility in an acute setting to help risk stratification in patients with ischaemic stroke and transient ischaemic attacks. Methods: The prospective cross-sectional study was conducted at the Gazi University Hospital, Ankara, Turkey, from November 2009 to June 2010. It comprised 143 consecutive patients of acute ischaemic stroke, 39 patients of transient ischaemic attacks and 60 healthy volunteers. SPSS 13 was used for statistical analysis, and so were t-test, one-way analysis of variance test and correlation analysis. Statistical significance was accepted at p <0.05. Results: Mean platelet volume results were significantly higher in patients with cortical infarction and transient ischaemic attack compared to the control group (p <0.001 and p <0.002). A statistically significant increase was also noted in hospitalised patients when compared with discharged patients from the emergency department (p <0.036). A weak positive correlation was identified between the National Institute of Health Stroke Scores and mean platelet volume levels (r=0.207; p <0.001). A significant relationship was identified between mean platelet volume levels and previous stroke (p <0.005). Conclusion: The measurement of mean platelet volume levels may provide useful diagnostic and prognostic information to emergency physicians caring for patients with transient ischaemic attack and ischaemic stroke. In patients with suspected neurological ischaemic symptoms, high levels may be considered as an atherosclerotic risk factor. (author)

Strategy for prioritizing whistleblowing with potential risks related to health services

Directory of Open Access Journals (Sweden)

Rafael Fernandes Barros

2017-11-01

Full Text Available Introduction: The Sanitary Surveillance of Health Services receives daily denunciations that refer to situations of risk that can hardly be measured quantitatively and attribute to some type of specific damage, in a context of great uncertainty. Objective: Considering such situations should be adequately addressed under the health risk paradigm, this work had as objective identifying notions about risk and its forms of analysis in the scope of Sanitary Surveillance of Health Services, as well as the existence of strategies and models in the analysis and treatment of denunciations. Method: An extensive literature review (through the Regional Portal of the BVS, databases SciELO and SciELO Books, and the journal Visa em Debate was conducted. Results: Although the results point to a relatively recent discussion regarding the model of potential risk analysis as an operational concept for the field of health surveillance in health services, there is no description of strategies or models applied to the analysis or treatment of whistleblowing. Thus, it is discussed and proposed a strategy for the initial analysis of reports with potential risk, which seeks to bring minimally objective criteria, in a field marked by enormous subjectivity. Conclusions: We conclude by indicating that the presented strategy is an initial instrument for the management of whistleblowing that must be discussed and adapted to the reality and context of health surveillance agencies.

Fertility drugs, reproductive strategies and ovarian cancer risk

OpenAIRE

Tomao, Federica; Lo Russo, Giuseppe; Spinelli, Gian Paolo; Stati, Valeria; Prete, Alessandra Anna; Prinzi, Natalie; Sinjari, Marsela; Vici, Patrizia; Papa, Anselmo; Chiotti, Maria Stefania; Benedetti Panici, Pierluigi; Tomao, Silverio

2014-01-01

Several adverse effects have been related to infertility treatments, such as cancer development. In particular, the relationship between infertility, reproductive strategies, and risk of gynecological cancers has aroused much interest in recent years. The evaluation of cancer risk among women treated for infertility is very complex, mainly because of many factors that can contribute to occurrence of cancer in these patients (including parity status). This article addresses the possible associ...

Simulation of atmosphere stratification in the HDR test facility with the CONTAIN code

International Nuclear Information System (INIS)

Skerlavaj, A.; Mavko, B.; Kljenak, I.

2001-01-01

The test E11.2 'Hydrogen distribution in loop flow geometry', which was performed in the Heissdampf Reaktor containment test facility in Germany, was simulated with the CONTAIN computer code. The predicted pressure history and thermal stratification are in relatively good agreement with the measurements. The compositional stratification within the containment was qualitatively well predicted, although the degree of the stratification in the dome area was slightly underestimated. The analysis of simulation results enabled a better understanding of the physical phenomena during the test.(author)

Social Stratification and Cooperative Behavior in Spatial Prisoners' Dilemma Games.

Directory of Open Access Journals (Sweden)

Peng Lu

Full Text Available It has been a long-lasting pursuit to promote cooperation, and this study aims to promote cooperation via the combination of social stratification and the spatial prisoners' dilemma game. It is previously assumed that agents share the identical payoff matrix, but the stratification or diversity exists and exerts influences in real societies. Thus, two additional classes, elites and scoundrels, derive from and coexist with the existing class, commons. Three classes have different payoff matrices. We construct a model where agents play the prisoners' dilemma game with neighbors. It indicates that stratification and temptation jointly influence cooperation. Temptation permanently reduces cooperation; elites play a positive role in promoting cooperation while scoundrels undermine it. As the temptation getting larger and larger, elites play a more and more positive and critical role while scoundrels' negative effect becomes weaker and weaker, and it is more obvious when temptation goes beyond its threshold.

Identification and management of cardiometabolic risk in Canada: a position paper by the cardiometabolic risk working group (executive summary).

Science.gov (United States)

Leiter, Lawrence A; Fitchett, David H; Gilbert, Richard E; Gupta, Milan; Mancini, G B John; McFarlane, Philip A; Ross, Robert; Teoh, Hwee; Verma, Subodh; Anand, Sonia; Camelon, Kathryn; Chow, Chi-Ming; Cox, Jafna L; Després, Jean-Pierre; Genest, Jacques; Harris, Stewart B; Lau, David C W; Lewanczuk, Richard; Liu, Peter P; Lonn, Eva M; McPherson, Ruth; Poirier, Paul; Qaadri, Shafiq; Rabasa-Lhoret, Rémi; Rabkin, Simon W; Sharma, Arya M; Steele, Andrew W; Stone, James A; Tardif, Jean-Claude; Tobe, Sheldon; Ur, Ehud

2011-01-01

With the objectives of clarifying the concepts related to "cardiometabolic risk," "metabolic syndrome" and "risk stratification" and presenting practical strategies to identify and reduce cardiovascular risk in multiethnic patient populations, the Cardiometabolic Working Group presents an executive summary of a detailed analysis and position paper that offers a comprehensive and consolidated approach to the identification and management of cardiometabolic risk. The above concepts overlap and relate to the atherogenic process and development of type 2 diabetes. However, there is confusion about what these terms mean and how they can best be used to improve our understanding of cardiovascular disease treatment and prevention. The concepts related to cardiometabolic risk, pathophysiology, and strategies for identification and management (including health behaviours, pharmacotherapy, and surgery) in the multiethnic Canadian population are presented. "Global cardiometabolic risk" is proposed as an umbrella term for a comprehensive list of existing and emerging factors that predict cardiovascular disease and/or type 2 diabetes. Health behaviour interventions (weight loss, physical activity, diet, smoking cessation) in people identified at high cardiometabolic risk are of critical importance given the emerging crisis of obesity and the consequent epidemic of type 2 diabetes. Vascular protective measures (health behaviours for all patients and pharmacotherapy in appropriate patients) are essential to reduce cardiometabolic risk, and there is growing consensus that a multidisciplinary approach is needed to adequately address cardiometabolic risk factors. Health care professionals must also consider ethnicity-related risk factors in order to appropriately evaluate all individuals in their diverse patient populations. Copyright © 2011 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Representing Reservoir Stratification in Land Surface and Earth System Models

Science.gov (United States)

Yigzaw, W.; Li, H. Y.; Leung, L. R.; Hejazi, M. I.; Voisin, N.; Payn, R. A.; Demissie, Y.

2017-12-01

A one-dimensional reservoir stratification modeling has been developed as part of Model for Scale Adaptive River Transport (MOSART), which is the river transport model used in the Accelerated Climate Modeling for Energy (ACME) and Community Earth System Model (CESM). Reservoirs play an important role in modulating the dynamic water, energy and biogeochemical cycles in the riverine system through nutrient sequestration and stratification. However, most earth system models include lake models that assume a simplified geometry featuring a constant depth and a constant surface area. As reservoir geometry has important effects on thermal stratification, we developed a new algorithm for deriving generic, stratified area-elevation-storage relationships that are applicable at regional and global scales using data from Global Reservoir and Dam database (GRanD). This new reservoir geometry dataset is then used to support the development of a reservoir stratification module within MOSART. The mixing of layers (energy and mass) in the reservoir is driven by eddy diffusion, vertical advection, and reservoir inflow and outflow. Upstream inflow into a reservoir is treated as an additional source/sink of energy, while downstream outflow represented a sink. Hourly atmospheric forcing from North American Land Assimilation System (NLDAS) Phase II and simulated daily runoff by ACME land component are used as inputs for the model over the contiguous United States for simulations between 2001-2010. The model is validated using selected observed temperature profile data in a number of reservoirs that are subject to various levels of regulation. The reservoir stratification module completes the representation of riverine mass and heat transfer in earth system models, which is a major step towards quantitative understanding of human influences on the terrestrial hydrological, ecological and biogeochemical cycles.

GFC-Robust Risk Management Strategies under the Basel Accord

NARCIS (Netherlands)

M.J. McAleer (Michael); J.A. Jiménez-Martín (Juan-Ángel); T. Pérez-Amaral (Teodosio)

2010-01-01

textabstractA risk management strategy is proposed as being robust to the Global Financial Crisis (GFC) by selecting a Value-at-Risk (VaR) forecast that combines the forecasts of different VaR models. The robust forecast is based on the median of the point VaR forecasts of a set of conditional

Risk communication strategy development using the aerospace systems engineering process

Science.gov (United States)

Dawson, S.; Sklar, M.

2004-01-01

This paper explains the goals and challenges of NASA's risk communication efforts and how the Aerospace Systems Engineering Process (ASEP) was used to map the risk communication strategy used at the Jet Propulsion Laboratory to achieve these goals.

MANAGING RISK BY COORDINATING INVESTMENT, MARKETING, AND PRODUCTION STRATEGIES

OpenAIRE

Johnson, Donald A.; Boehlje, Michael

1983-01-01

This study of the farm firm integrates long run investment and financial decisions, and short-run production and marketing decisions into a single decision framework that includes both time and risk. The results suggest that the use of various strategies for managing market risks allow the entrepreneur to accept mores risk in investing and producing; and that an integrated analysis of production, marketing and investment-financing alternatives is essential to make accurate recommendations abo...

Numerical investigation on thermal stratification and striping phenomena in various coolants

International Nuclear Information System (INIS)

Zumao Yang; Muramatsu, Toshiharu

2000-02-01

It is important to study thermal stratification and striping phenomena for they can induce thermal fatigue failure of structures. This presentation uses the AQUA code, which has been developed in Japan Nuclear Cycle Development Institute (JNC), to investigate the characteristics of these thermal phenomena in water, liquid sodium, liquid lead and carbon dioxide gas. There are altogether eight calculated cases with same Richardson number and initial inlet hot velocity in thermal stratification calculations, in which four cases have same velocity difference between inlet hot and cold fluid, the other four cases with same temperature difference. The calculated results show: (1) The fluid's properties and initial conditions have considerable effects on thermal stratification, which is decided by the combination of such as thermal conduction, viscous dissipation and buoyant force, etc., and (2) The gas has distinctive thermal stratification characteristics from those of liquid because for horizontal flow in the transportation of momentum and energy, the drastic exchange usually happens at the hot-cold interface for liquid, however, the buoyancy and natural convection make the quick exchange position depart from the hot-cold interface for gas. In thermal striping analysis, only the first step work has been finished. The calculated results show: (1) the vertical flow has some difference in thermal stratification characteristics from those of horizontal flow, and (2) For deep thermal striping analysis in the calculated area, more attention should be paid to the center area along Z-direction for liquid and small velocity area for gas. (author)

Vertical mixing and coherent anticyclones in the ocean: the role of stratification

Directory of Open Access Journals (Sweden)

I. Koszalka

2010-01-01

Full Text Available The role played by wind-forced anticyclones in the vertical transport and mixing at the ocean mesoscale is investigated with a primitive-equation numerical model in an idealized configuration. The focus of this work is to determine how the stratification impacts such transport.

The flows, forced only at the surface by an idealized wind forcing, are predominantly horizontal and, on average, quasigeostrophic. Inside vortex cores and intense filaments, however, the dynamics is strongly ageostrophic.

Mesoscale anticyclones appear as "islands" of increased penetration of wind energy into the ocean interior and they represent the maxima of available potential energy. The amount of available potential energy is directly correlated with the degree of stratification.

The wind energy injected at the surface is transferred at depth through the generation and subsequent straining effect of Vortex Rossby Waves (VRWs, and through near-inertial internal oscillations trapped inside anticyclonic vortices. Both these mechanisms are affected by stratification. Stronger transfer but larger confinement close to the surface is found when the stratification is stronger. For weaker stratification, vertical mixing close to the surface is less intense but below about 150 m attains substantially higher values due to an increased contribution of both VRWs, whose time scale is on the order of few days, and of near-inertial motions, with a time scale of few hours.

Thermal stratification in a scaled-down suppression pool of the Fukushima Daiichi nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Jo, Byeongnam, E-mail: jo@vis.t.u-tokyo.ac.jp [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan); Erkan, Nejdet [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan); Takahashi, Shinji [Department of Nuclear Engineering and Management, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Song, Daehun [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan); Hyundai and Kia Corporate R& D Division, Hyundai Motors, 772-1, Jangduk-dong, Hwaseong-Si, Gyeonggi-Do 445-706 (Korea, Republic of); Sagawa, Wataru; Okamoto, Koji [Nuclear Professional School, The University of Tokyo, 2-22 Shirakata, Tokai-mura, Ibaraki 319-1188 (Japan)

2016-08-15

Highlights: • Thermal stratification was reproduced in a scaled-down suppression pool of the Fukushima Daiichi nuclear power plants. • Horizontal temperature profiles were uniform in the toroidal suppression pool. • Subcooling-steam flow rate map of thermal stratification was obtained. • Steam bubble-induced flow model in suppression pool was suggested. • Bubble frequency strongly depends on the steam flow rate. - Abstract: Thermal stratification in the suppression pool of the Fukushima Daiichi nuclear power plants was experimentally investigated in sub-atmospheric pressure conditions using a 1/20 scale torus shaped setup. The thermal stratification was reproduced in the scaled-down suppression pool and the effect of the steam flow rate on different thermal stratification behaviors was examined for a wide range of steam flow rates. A sparger-type steam injection pipe that emulated Fukushima Daiichi Unit 3 (F1U3) was used. The steam was injected horizontally through 132 holes. The development (formation and disappearance) of thermal stratification was significantly affected by the steam flow rate. Interestingly, the thermal stratification in the suppression pool vanished when subcooling became lower than approximately 5 °C. This occurred because steam bubbles are not well condensed at low subcooling temperatures; therefore, those bubbles generate significant upward momentum, leading to mixing of the water in the suppression pool.

Role of imaging in evaluation of sudden cardiac death risk in hypertrophic cardiomyopathy.

Science.gov (United States)

Geske, Jeffrey B; Ommen, Steve R

2015-09-01

Hypertrophic cardiomyopathy (HCM) is the most common heritable cardiomyopathy and is associated with sudden cardiac death (SCD) - an uncommon but devastating clinical outcome. This review is designed to assess the role of imaging in established risk factor assessment and its role in emerging SCD risk stratification. Recent publications have highlighted the crucial role of imaging in HCM SCD risk stratification. Left ventricular hypertrophy assessment remains the key imaging determinant of risk. Data continue to emerge on the role of systolic dysfunction, apical aneurysms, left atrial enlargement and left ventricular outflow tract obstruction as markers of risk. Quantitative assessment of delayed myocardial enhancement and T1 mapping on cardiac MRI continue to evolve. Recent multicenter trials have allowed multivariate SCD risk assessment in large HCM cohorts. Given aggregate risk with presence of multiple risk factors, a single parameter should not be used in isolation to determine implantable cardiac defibrillator candidacy. Use of all available imaging data, including cardiac magnetic resonance tissue characterization, allows a comprehensive approach to SCD stratification and implantable cardiac defibrillator decision-making.

Mathematics, Pricing, Market Risk Management and Trading Strategies for Financial Derivatives (2/3)

CERN Multimedia

CERN. Geneva; Coffey, Brian

2009-01-01

Market Trading and Risk Management of Vanilla FX Options - Measures of Market Risk - Implied Volatility - FX Risk Reversals, FX Strangles - Valuation and Risk Calculations - Risk Management - Market Trading Strategies

Stratification of living organisms in ballast tanks: how do organism concentrations vary as ballast water is discharged?

Science.gov (United States)

First, Matthew R; Robbins-Wamsley, Stephanie H; Riley, Scott C; Moser, Cameron S; Smith, George E; Tamburri, Mario N; Drake, Lisa A

2013-05-07

Vertical migrations of living organisms and settling of particle-attached organisms lead to uneven distributions of biota at different depths in the water column. In ballast tanks, heterogeneity could lead to different population estimates depending on the portion of the discharge sampled. For example, concentrations of organisms exceeding a discharge standard may not be detected if sampling occurs during periods of the discharge when concentrations are low. To determine the degree of stratification, water from ballast tanks was sampled at two experimental facilities as the tanks were drained after water was held for 1 or 5 days. Living organisms ≥50 μm were counted in discrete segments of the drain (e.g., the first 20 min of the drain operation, the second 20 min interval, etc.), thus representing different strata in the tank. In 1 and 5 day trials at both facilities, concentrations of organisms varied among drain segments, and the patterns of stratification varied among replicate trials. From numerical simulations, the optimal sampling strategy for stratified tanks is to collect multiple time-integrated samples spaced relatively evenly throughout the discharge event.

The formation of low-angle eolian stratification through the migration of protodunes

Science.gov (United States)

Ewing, R. C.; Phillips, J. D.; Weymer, B. A.; Barrineaux, P.; Bowling, R.; Nittrouer, J. A.

2017-12-01

Protodunes are low-relief, slipfaceless migrating bed forms that represent the emergent form of eolian sand dunes. Protodunes develop as cm-scale topography out of a flat bed of sand and evolve spatially and temporally into dunes with angle-of-repose slipfaces. Protodunes at White Sands Dune Field in New Mexico form at the upwind, trailing margin of the field, on dune stoss slopes, and in interdune areas. Here we analyze protodunes at the upwind margin of White Sands by coupling 200 mHz ground penetrating radar (GPR) with time-series high-resolution topography to characterize the origin and evolution of protodune stratification and the stratigraphic transition into fully developed dunes. We surveyed a 780m transect in the resultant transport direction of the dune field from SW to NE from sand patches through protodunes and into the first dune. We used airborne lidar surveys and structure-from-motion photogrammetry from 2007, 2008, 2009, 2010, 2015, and 2016. We find that protodune stratification forms at angles between 0-10 degrees by protodune migration. Dip angles increase as protodune amplitude increases along the transect. Accumulation of low-angle stratification increases across the first 650m and ranges from none to subcritical. Nearly aggradational accumulation of low-angle stratification occurs over the last 100m and is a precursor to angle-of-repose slipface formation. The origins of the aggradation and slipface development appear to be linked to protodune merging, dune interactions, and possibly to the development of a dune field-scale boundary layer. Protodunes and the formation of low-angle stratification at the upwind margin of White Sands are a good analog to the initiation of dune field development from sand sheets and the formation of low-angle stratification found at the base of eolian successions in the stratigraphic record.

Fatigue of LMFBR piping due to flow stratification

International Nuclear Information System (INIS)

Woodward, W.S.

1983-01-01

Flow stratification due to reverse flow was simulated in a 1/5-scale water model of a LMFBR primary pipe loop. The stratified flow was observed to have a dynamic interface region which oscillated in a wave pattern. The behavior of the interface was characterized in terms of location, local temperature fluctuation and duration for various reverse flow conditions. A structural assessment was performed to determine the effects of stratified flow on the fatigue life of the pipe. Both the static and dynamic aspects of flow stratification were examined. The dynamic interface produces thermal striping on the inside of the pipe wall which is shown to have the most deleterious effect on the pipe wall and produce significant fatigue damage relative to a static interface

Fatigue of LMFBR piping due to flow stratification

Energy Technology Data Exchange (ETDEWEB)

Woodward, W.S.

1983-01-01

Flow stratification due to reverse flow was simulated in a 1/5-scale water model of a LMFBR primary pipe loop. The stratified flow was observed to have a dynamic interface region which oscillated in a wave pattern. The behavior of the interface was characterized in terms of location, local temperature fluctuation and duration for various reverse flow conditions. A structural assessment was performed to determine the effects of stratified flow on the fatigue life of the pipe. Both the static and dynamic aspects of flow stratification were examined. The dynamic interface produces thermal striping on the inside of the pipe wall which is shown to have the most deleterious effect on the pipe wall and produce significant fatigue damage relative to a static interface.

Cornerstones of the Austrian radon risk communication strategy

International Nuclear Information System (INIS)

Kunte, A.; Ringer, W.

2015-01-01

On behalf of the Federal Ministry of Agriculture, Forestry, Environment and Water Management (BMLFUW), the National Radon Centre of Austria developed the National Radon Risk Communication Strategy. The superior goal is the reduction of the radon exposure of Austrian citizens as well as the reduction of radon-related lung cancer deaths. Austria, like many other countries, follows the approach to raise awareness and to inform the public to achieve this goal. The presented strategy deals with the question of how radon protection issues can be communicated to the public, existing fears can be reduced and affected people can be motivated to take action (perform a radon test, if necessary, mitigate or install preventive measures in new buildings). The cornerstones of the National Radon Risk Communication Strategy can be summarized as follows: - Definition of communication goals - Identification and categorization of target groups - Development of specific key messages for each of the target groups - Determination of communication channels and assessment of their efficiency - Integration of the radon issue in education and training - Cooperation with relevant organizations and platforms. The communication objectives, target groups and communication paths (and their evaluation) will be discussed during the presentation in detail.

Formulation parameters influencing self-stratification of coatings

NARCIS (Netherlands)

Vink, P.; Bots, T.L.

1996-01-01

Research was carried out aimed at the development of self-stratifying paints for steel which after application during film formation spontaneously form two well established layers of primer and top coat. The parameters affecting stratification were investigated for combinations of epoxy resins and

Estratificación epidemiológica en el control de los factores de riesgo de la tuberculosis Epidemiological stratification to control the risk factors of tuberculosis

Directory of Open Access Journals (Sweden)

Elba Nieves Moreno Díaz

2011-12-01

Full Text Available Se realizó un estudio descriptivo longitudinal, con el objetivo de implementar la estratificación epidemiológica en el control de los factores de riesgo de la tuberculosis, provincia Pinar del Río, 2008-2010. El universo de estudio lo constituyó, los habitantes de la provincia en cada uno de los años estudiados. Se revisó el registro de dispensarización y las encuestas epidemiológicas; de ellos se obtuvieron los factores de riesgo: alcoholismo, hábito de fumar, diabetes mellitus, ancianos solos, desnutrición, inmunodeprimidos y casos viviendo con VIH/Sida. Para el procesamiento de la información se trabajó con Microsoft Excel y MapInfo Professional. Se utilizó la metodología estratificación epidemiológica de riesgo hasta nivel municipal; los estratos para los factores de riesgo como para la enfermedad, se clasificaron en: muy alto, alto, mediano y bajo riesgo. Para determinar la significación de cambios se utilizó la prueba Mc Nemar. Los resultados mostraron que en el 2009, el 50% de los municipios que en la estratificación del 2008 estaban en el estrato de muy alto y alto riesgo, el 85,7% cambiaran de estratos, lo que indica un mejor control de los factores de riesgo. El proceso de estratificación en el 2010, no logró cambios favorables en los municipios con mayor riesgo en el 2008, estando el 65% clasificado en estratos de muy alto y alto riesgo, pues el plan de acción previsto, no fue ejecutado con efectividad y seriedad por los jefes de programa, debido a inestabilidad y ausencia de los mismos en los municipios de mayor riesgo.A descriptive, longitudinal study aimed at implementing epidemiological stratification to control the risk factors of tuberculosis in Pinar del Rio province was carried out form 2008 to 2010. The target group was comprised of the inhabitants of the province for each of the years under study. Records and epidemiological survey were revised; taking into account the risk factors of alcoholism

Investigating Summer Thermal Stratification in Lake Ontario

Science.gov (United States)

James, S. C.; Arifin, R. R.; Craig, P. M.; Hamlet, A. F.

2017-12-01

Seasonal temperature variations establish strong vertical density gradients (thermoclines) between the epilimnion and hypolimnion. Accurate simulation of vertical mixing and seasonal stratification of large lakes is a crucial element of the thermodynamic coupling between lakes and the atmosphere in integrated models. Time-varying thermal stratification patterns can be accurately simulated with the versatile Environmental Fluid Dynamics Code (EFDC). Lake Ontario bathymetry was interpolated onto a 2-km-resolution curvilinear grid with vertical layering using a new approach in EFDC+, the so-called "sigma-zed" coordinate system which allows the number of vertical layers to be varied based on water depth. Inflow from the Niagara River and outflow to the St. Lawrence River in conjunction with hourly meteorological data from seven local weather stations plus three-hourly data from the North American Regional Reanalysis govern the hydrodynamic and thermodynamic responses of the Lake. EFDC+'s evaporation algorithm was updated to more accurately simulate net surface heat fluxes. A new vertical mixing scheme from Vinçon-Leite that implements different eddy diffusivity formulations above and below the thermocline was compared to results from the original Mellor-Yamada vertical mixing scheme. The model was calibrated by adjusting solar-radiation absorption coefficients in addition to background horizontal and vertical mixing parameters. Model skill was evaluated by comparing measured and simulated vertical temperature profiles at shallow (20 m) and deep (180 m) locations on the Lake. These model improvements, especially the new sigma-zed vertical discretization, accurately capture thermal-stratification patterns with low root-mean-squared errors when using the Vinçon-Leite vertical mixing scheme.

Determining the core stratification in white dwarfs with asteroseismology

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Charpinet S.

2017-01-01

Full Text Available Using the forward modeling approach and a new parameterization for the core chemical stratification in ZZ Ceti stars, we test several situations typical of the usually limited constraints available, such as small numbers of observed independent modes, to carry out asteroseismology of these stars. We find that, even with a limited number of modes, the core chemical stratification (in particular, the location of the steep chemical transitions expected in the oxygen profile can be determined quite precisely due to the significant sensitivity of some confined modes to partial reflexion (trapping effects. These effects are similar to the well known trapping induced by the shallower chemical transitions at the edge of the core and at the bottom of the H-rich envelope. We also find that success to unravel the core structure depends on the information content of the available seismic data. In some cases, it may not be possible to isolate a unique, well-defined seismic solution and the problem remains degenerate. Our results establish that constraining the core chemical stratification in white dwarf stars based solely on asteroseismology is possible, an opportunity that we have started to exploit.

[Strategies for reducing risks in smoking: opportunity or threat].

Science.gov (United States)

Córdoba, Rodrigo; Nerín, Isabel

2009-12-01

The smoking control policies recommended by the World Health Organisation have achieved a slight decrease in smoking prevalence in the developed countries, although associated mortality is still very high. The use of tobacco products other than cigarettes and even medicinal nicotine (known as nicotine replacement therapy (NRT)) has been proposed as a risk reduction strategy. Among the tobacco products with less individual risk than cigarettes would be any type of tobacco without smoke (smokeless) with a low content in nitrosamines and modified cigarettes; both forms included under the PREP (Potentially Reduced Exposure Products) concept. The idea would be to promote these products among those who cannot quit smoking or wish to reduce their risk without giving up nicotine intake. The possible effects of risk reduction strategies, including PREP, on the decreased prevalence and morbidity and mortality are reviewed, and the possible implications that this measure could have in our country are analysed. Tobacco control measures in Spain are recent and still insufficient. Therefore, the current priority in Spain is the development of policies of control that have shown to more than effective. The marketing and advertising of new tobacco products, even with reduced potential risk, seems more a serious threat than an opportunity for the development of smoking control policies.

Risk management - unappreciated instrument of supply chain management strategy

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Wojciech Machowiak

2012-12-01

Full Text Available Background: Unlike Enterprise Risk Management, which is certainly quite well rooted in business practice, Supply Chain Risk Management (SCRM still continues to be dynamically developing subject of academic research, whereas its practical applications are rather scarce. Material and methods: On the basis of broad review of the current state of the art in world literature, significant  relevancies to the core processes and enterprise strategy are discussed.   Results: The paper shows some interesting from the enterprise's performance and competitiveness point of view additional benefits, potentially resulting from the proactive, consistent and effective implementation of the SCRM system. Conclusions: Some additional advantages from proactive supply chain risk management account for perceiving SCRM as multifunctional instrument of strategic SC management, exceeding established understanding RM as security and threat-prevention  tool only. Positive influence from SCRM onto SC performance and competitiveness can make reasonable to enhance its position within SCM strategy.

Coolant stratification and its thermohydrodynamic specificity under natural circulation in horizontal steam generator collectors

Energy Technology Data Exchange (ETDEWEB)

Blagovechtchenski, A.; Leontieva, V.; Mitriukhin, A. [Saint-Petersburg Technical Univ. (Russian Federation)

1997-12-31

The experiments and the test facilities for the study of the stratification phenomenon in the hot plenum of reactor and the upper parts of the steam generator collectors in a nuclear power plant are described. The aim of the experiments was to define the conditions of the stratification initiation, to study the temperature field in the upper part, the definition of the characteristics in the stratification layer, and also to study the factors which cause the intensity of the stagnant volume cooling.

Coolant stratification and its thermohydrodynamic specificity under natural circulation in horizontal steam generator collectors

Energy Technology Data Exchange (ETDEWEB)

Blagovechtchenski, A; Leontieva, V; Mitriukhin, A [Saint-Petersburg Technical Univ. (Russian Federation)

1998-12-31

The experiments and the test facilities for the study of the stratification phenomenon in the hot plenum of reactor and the upper parts of the steam generator collectors in a nuclear power plant are described. The aim of the experiments was to define the conditions of the stratification initiation, to study the temperature field in the upper part, the definition of the characteristics in the stratification layer, and also to study the factors which cause the intensity of the stagnant volume cooling.

Risk comparison of different treatment and disposal strategies of high level liquid radioactive waste

International Nuclear Information System (INIS)

Fang Dong

1997-01-01

The risk of different treatment and disposal strategies of high level liquid radioactive waste from spent fuel reprocessing is estimated and compared. The conclusions obtained are that risk difference from these strategies is very small and high level liquid waste can be reduced to middle and low level waste, if the decontamination factor for 99 Tc is large enough, which is the largest risk contributor in the high level radioactive waste from spent fuel reprocessing. It is also shown that the risk of high level radioactive waste could be reduced by the technical strategy of combining partitioning and transmutation

Randomization in clinical trials: stratification or minimization? The HERMES free simulation software.

Science.gov (United States)

Fron Chabouis, Hélène; Chabouis, Francis; Gillaizeau, Florence; Durieux, Pierre; Chatellier, Gilles; Ruse, N Dorin; Attal, Jean-Pierre

2014-01-01

Operative clinical trials are often small and open-label. Randomization is therefore very important. Stratification and minimization are two randomization options in such trials. The first aim of this study was to compare stratification and minimization in terms of predictability and balance in order to help investigators choose the most appropriate allocation method. Our second aim was to evaluate the influence of various parameters on the performance of these techniques. The created software generated patients according to chosen trial parameters (e.g., number of important prognostic factors, number of operators or centers, etc.) and computed predictability and balance indicators for several stratification and minimization methods over a given number of simulations. Block size and proportion of random allocations could be chosen. A reference trial was chosen (50 patients, 1 prognostic factor, and 2 operators) and eight other trials derived from this reference trial were modeled. Predictability and balance indicators were calculated from 10,000 simulations per trial. Minimization performed better with complex trials (e.g., smaller sample size, increasing number of prognostic factors, and operators); stratification imbalance increased when the number of strata increased. An inverse correlation between imbalance and predictability was observed. A compromise between predictability and imbalance still has to be found by the investigator but our software (HERMES) gives concrete reasons for choosing between stratification and minimization; it can be downloaded free of charge. This software will help investigators choose the appropriate randomization method in future two-arm trials.

Improving Fall Risk Factor Identification and Documentation of Risk Reduction Strategies by Rehabilitation Therapists through Continuing Education

Science.gov (United States)

Karnes, Michele J.

2011-01-01

This static group comparison study determined that an educational intervention was effective in increasing fall risk factor assessment, documentation of fall risk factors, and strategies devised to reduce fall risk factors by rehabilitation therapists for their older adult outpatients in clinics. Results showed that experimental group identified…

Síndromes coronarianas agudas: tratamento e estratificação de risco Acute coronary syndromes: treatment and risk stratification

Directory of Open Access Journals (Sweden)

Antonio Eduardo Pereira Pesaro

2008-06-01

variable degrees of coronary obstruction. Patients with total occlusion may present with acute ST Elevation Myocardial Infarction (STEMI. Partial vessel obstruction may result in Non-ST-Elevation Acute Myocardial Infarction (NSTEMI or unstable angina (UA. Clinical symptoms and electrocardiographic changes are the main components of identification of ACS. The rapid and effective triage of such patients regarding presence or absence of ST-segment elevation is critical to dictate further therapeutic strategies. The objective of this chapter was to review current evidence and recommendations for the evaluation and early treatment of acute coronary syndromes. CONTENTS: We performed a clinical review using the electronic databases MedLine and LILACS from January 1990 to September 2007. CONCLUSIONS: Reperfusion of the infarct-related artery is the cornerstone of therapy for STEMI. Fibrinolysis and percutaneous coronary intervention are both well established as effective options. Management of UA/NSTEMI patients requires early risk stratification. High-risk patients should undergo an early invasive strategy that consists in performance of cardiac catheterization in the first 24 to 48 hours of presentation.

Evolving Use of Natriuretic Peptides as Part of Strategies for Heart Failure Prevention.

Science.gov (United States)

McDonald, Ken; Wilkinson, Mark

2017-01-01

Heart failure (HF) remains one of the major cardiovascular challenges to the Western world. Once established, HF is characterized by compromised life expectancy and quality of life with considerable dependence on hospital care for episodic clinical deterioration. Much is understood about the risk factors that predispose to the development of HF. With such a broad range of factors, it is clear that there is a large population at risk, potentially in excess of 25% of the adult population. Therein lies the major challenge at the outset of our efforts to prevent HF. With such a large population at risk, how do we develop an effective prevention strategy? HF prevention requires a multimodal approach. In this review, we focus primarily on the role of natriuretic peptide (NP) as a tool in a prevention strategy. Prevention of HF is a major public health challenge, underlined by the concerning epidemiological trends, the associated costs, and the continued difficulty to find effective therapies for the growing number of patients with preserved systolic function HF. Population-based approaches focusing on lifestyle and risk factor control have made some impact but not to a satisfactory level and also tend to result in a uniform approach across a population with different risk profiles. Individualizing risk is therefore required, with emerging data indicating that NP-guided risk stratification and intervention can reduce downstream incident HF and other cardiovascular events. © 2016 American Association for Clinical Chemistry.

Dependence of offshore wind turbine fatigue loads on atmospheric stratification

DEFF Research Database (Denmark)