The Rey Auditory Verbal Learning Test forced-choice recognition task: Base-rate data and norms.

PubMed

Poreh, Amir; Bezdicek, Ondrej; Korobkova, Irina; Levin, Jennifer B; Dines, Philipp

2016-01-01

The present study describes a novel Forced-Choice Response (FCR) index for detecting poor effort on the Rey Auditory Verbal Learning Test (RAVLT). This retrospective study analyzes the performance of 4 groups on the new index: clinically referred patients with suspected dementia, forensic patients identified as not exhibiting adequate effort on other measures of response bias, students who simulated poor effort, and a large normative sample collected in the Gulf State of Oman. Using sensitivity and specificity analyses, the study shows that much like the California Verbal Learning Test-Second Edition FCR index, the RAVLT FCR index misses a proportion of individuals with inadequate effort (low sensitivity), but those who fail this measure are highly likely to be exhibiting poor effort (high specificity). The limitations and benefits of utilizing the RAVLT FCR index in clinical practice are discussed.

Fatty liver index vs waist circumference for predicting non-alcoholic fatty liver disease.

PubMed

Motamed, Nima; Sohrabi, Masoudreza; Ajdarkosh, Hossein; Hemmasi, Gholamreza; Maadi, Mansooreh; Sayeedian, Fatemeh Sima; Pirzad, Reza; Abedi, Khadijeh; Aghapour, Sivil; Fallahnezhad, Mojtaba; Zamani, Farhad

2016-03-14

To determine the discriminatory performance of fatty liver index (FLI) for non-alcoholic fatty liver disease (NAFLD). The data of 5052 subjects aged over 18 years were analyzed. FLI was calculated from body mass index, waist circumference (WC), triglyceride, and gamma glutamyl transferase data. Logistic regression analysis was conducted to determine the association between FLI and NAFLD. The discriminatory performance of FLI in the diagnosis of NAFLD was evaluated by receiver operating characteristic analysis. Area under the curves (AUCs) and related confidence intervals were estimated. Optimal cutoff points of FLI in the diagnosis of NAFLD were determined based on the maximum values of Youden's index. The mean age of men and women in the study population were 44.8 ± 16.8 and 43.78 ± 15.43, respectively (P = 0.0216). The prevalence of NAFLD was 40.1% in men and 44.2% in women (P < 0.0017). FLI was strongly associated with NAFLD, so that even a one unit increase in FLI increased the chance of developing NAFLD by 5.8% (OR = 1.058, 95%CI: 1.054-1.063, P < 0.0001). Although FLI showed good performance in the diagnosis of NAFLD (AUC = 0.8656 (95%CI: 0.8548-0.8764), there was no significant difference with regards to WC (AUC = 0.8533, 95%CI: 0.8419-0.8646). The performance of FLI was not significantly different between men (AUC = 0.8648, 95%CI: 0.8505-0.8791) and women (AUC = 0.8682, 95%CI: 0.8513-0.8851). The highest performance with regards to age was related to the 18-39 age group (AUC = 0.8930, 95%CI: 0.8766-0.9093). The optimal cutoff points of FLI were 46.9 in men (sensitivity = 0.8242, specificity = 0.7687, Youden's index = 0.5929) and 53.8 in women (sensitivity = 0.8233, specificity = 0.7655, Youden's index = 0.5888). Although FLI had acceptable discriminatory power in the diagnosis of NAFLD, WC was a simpler and more accessible index with a similar performance.

Continued Evaluation of Gear Condition Indicator Performance on Rotorcraft Fleet

NASA Technical Reports Server (NTRS)

Delgado, Irebert R.; Dempsey, Paula J.; Antolick, Lance J.; Wade, Daniel R.

2013-01-01

This paper details analyses of condition indicator performance for the helicopter nose gearbox within the U.S. Army's Condition-Based Maintenance Program. Ten nose gearbox data sets underwent two specific analyses. A mean condition indicator level analysis was performed where condition indicator performance was based on a 'batting average' measured before and after part replacement. Two specific condition indicators, Diagnostic Algorithm 1 and Sideband Index, were found to perform well for the data sets studied. A condition indicator versus gear wear analysis was also performed, where gear wear photographs and descriptions from Army tear-down analyses were categorized based on ANSI/AGMA 1010-E95 standards. Seven nose gearbox data sets were analyzed and correlated with condition indicators Diagnostic Algorithm 1 and Sideband Index. Both were found to be most responsive to gear wear cases of micropitting and spalling. Input pinion nose gear box condition indicators were found to be more responsive to part replacement during overhaul than their corresponding output gear nose gear box condition indicators.

Rock Drilling Performance Evaluation by an Energy Dissipation Based Rock Brittleness Index

NASA Astrophysics Data System (ADS)

Munoz, H.; Taheri, A.; Chanda, E. K.

2016-08-01

To reliably estimate drilling performance both tool-rock interaction laws along with a proper rock brittleness index are required to be implemented. In this study, the performance of a single polycrystalline diamond compact (PDC) cutter cutting and different drilling methods including PDC rotary drilling, roller-cone rotary drilling and percussive drilling were investigated. To investigate drilling performance by rock strength properties, laboratory PDC cutting tests were performed on different rocks to obtain cutting parameters. In addition, results of laboratory and field drilling on different rocks found elsewhere in literature were used. Laboratory and field cutting and drilling test results were coupled with values of a new rock brittleness index proposed herein and developed based on energy dissipation withdrawn from the complete stress-strain curve in uniaxial compression. To quantify cutting and drilling performance, the intrinsic specific energy in rotary-cutting action, i.e. the energy consumed in pure cutting action, and drilling penetration rate values in percussive action were used. The results show that the new energy-based brittleness index successfully describes the performance of different cutting and drilling methods and therefore is relevant to assess drilling performance for engineering applications.

Diagnostic performance of neck circumference to identify overweight and obesity as defined by body mass index in children and adolescents: systematic review and meta-analysis.

PubMed

Ma, Chunming; Wang, Rui; Liu, Yue; Lu, Qiang; Liu, Xiaoli; Yin, Fuzai

2017-05-01

The neck circumference (NC) has been shown to be an accurate index for screening overweight and obesity in children and adolescents. To perform a meta-analysis to assess the performance of NC for the assessment of overweight and obesity. Data sources were PubMed and EMBASE up to March 2016. Studies providing measures of diagnostic performance of NC and using body mass index as reference standard were included. Six eligible studies that evaluated 11 214 children and adolescents aged 6-18 years were included in the meta-analysis. NC showed pooled sensitivity to detect high body mass index of 0.780 (95% confidence interval [CI] = 0.765-0.794), specificity of 0.746 (95% CI =  0.736-0.756) and a diagnostic odds ratio of 17.343 (95% CI =  8.743-34.405). The NC had moderate diagnostic accuracy for identifying overweight and obesity in children and adolescents.

Diagnosis-Specific Prognostic Factors, Indexes, and Treatment Outcomes for Patients With Newly Diagnosed Brain Metastases: A Multi-Institutional Analysis of 4,259 Patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sperduto, Paul W., E-mail: psperduto@mropa.co; Chao, Samuel T.; Sneed, Penny K.

2010-07-01

Purpose: Controversy endures regarding the optimal treatment of patients with brain metastases (BMs). Debate persists, despite many randomized trials, perhaps because BM patients are a heterogeneous population. The purpose of the present study was to identify significant diagnosis-specific prognostic factors and indexes (Diagnosis-Specific Graded Prognostic Assessment [DS-GPA]). Methods and Materials: A retrospective database of 5,067 patients treated for BMs between 1985 and 2007 was generated from 11 institutions. After exclusion of the patients with recurrent BMs or incomplete data, 4,259 patients with newly diagnosed BMs remained eligible for analysis. Univariate and multivariate analyses of the prognostic factors and outcomes bymore » primary site and treatment were performed. The significant prognostic factors were determined and used to define the DS-GPA prognostic indexes. The DS-GPA scores were calculated and correlated with the outcomes, stratified by diagnosis and treatment. Results: The significant prognostic factors varied by diagnosis. For non-small-cell lung cancer and small-cell lung cancer, the significant prognostic factors were Karnofsky performance status, age, presence of extracranial metastases, and number of BMs, confirming the original GPA for these diagnoses. For melanoma and renal cell cancer, the significant prognostic factors were Karnofsky performance status and the number of BMs. For breast and gastrointestinal cancer, the only significant prognostic factor was the Karnofsky performance status. Two new DS-GPA indexes were thus designed for breast/gastrointestinal cancer and melanoma/renal cell carcinoma. The median survival by GPA score, diagnosis, and treatment were determined. Conclusion: The prognostic factors for BM patients varied by diagnosis. The original GPA was confirmed for non-small-cell lung cancer and small-cell lung cancer. New DS-GPA indexes were determined for other histologic types and correlated with the outcome, and statistical separation between the groups was confirmed. These data should be considered in the design of future randomized trials and in clinical decision-making.« less

Diagnostic performance of body mass index to identify excess body fat in children with cerebral palsy.

PubMed

Duran, Ibrahim; Schulze, Josefa; Martakis, KyriakoS; Stark, Christina; Schoenau, Eckhard

2018-03-07

To assess the diagnostic performance of body mass index (BMI) cut-off values according to recommendations of the World Health Organization (WHO), the World Obesity Federation (WOF), and the German Society for Adiposity (DAG) to identify excess body fat in children with cerebral palsy (CP). The present study was a monocentric retrospective analysis of prospectively collected data among children and adolescents with CP participating in a rehabilitation programme. Excess body fat was defined as a body fat percentage above the 85th centile assessed by dual-energy X-ray absorptiometry. In total, 329 children (181 males, 148 females) with CP were eligible for analysis. The mean age was 12 years 4 months (standard deviation 2y 9mo). The BMI cut-off values for 'overweight' according to the WHO, WOF, and DAG showed the following sensitivities and specificities for the prediction of excess body fat in our population: WHO: sensitivity 0.768 (95% confidence interval [CI] 0.636-0.870), specificity 0.894 (95% CI 0.851-0.928); WOF: sensitivity 0.696 (95% CI 0.559-0.812), specificity 0.934 (95% CI 0.898-0.960); DAG: sensitivity 0.411 (95% CI 0.281-0.550), specificity 0.993 (95% CI 0.974-0.999). Body mass index showed high specificity, but low sensitivity in children with CP. Thus, 'normal-weight obese' children with CP were overlooked, when assessing excess body fat only using BMI. Excess body fat in children with cerebral palsy (CP) is less common than previously reported. Body mass index (BMI) had high specificity but low sensitivity in detecting excess body fat in children with CP. BMI evaluation criteria of the German Society for Adiposity could be improved in children with CP. © 2018 Mac Keith Press.

Validation of the National Aeronautics and Space Administration Task Load Index as a tool to evaluate the learning curve for endoscopy training.

PubMed

Mohamed, Rachid; Raman, Maitreyi; Anderson, John; McLaughlin, Kevin; Rostom, Alaa; Coderre, Sylvain

2014-03-01

Although workplace workload assessments exist in different fields, an endoscopy-specific workload assessment tool is lacking. To validate such a workload tool and use it to map the progression of novice trainees in gastroenterology in performing their first endoscopies. The National Aeronautics and Space Administration Task Load Index (NASA-TLX) workload assessment tool was completed by eight novice trainees in gastroenterology and 10 practicing gastroenterologists⁄surgeons. An exploratory factor analysis was performed to construct a streamlined endoscopy-specific task load index, which was subsequently validated. The 'Endoscopy Task Load Index' was used to monitor progression of trainee exertion and self-assessed performance over their first 40 procedures. From the factor analysis of the NASA-TLX, two principal components emerged: a measure of exertion and a measure of self-efficacy. These items became the components of the newly validated Endoscopy Task Load Index. There was a steady decline in self-perceived exertion over the training period, which was more rapid for gastroscopy than colonoscopy. The self-efficacy scores for gastroscopy rapidly increased over the first few procedures, reaching a plateau after this period of time. For colonoscopy, there was a progressive increase in reported self-efficacy over the first three quartiles of procedures, followed by a drop in self-efficacy scores over the final quartile. The present study validated an Endoscopy Task Load Index that can be completed in <1 min. Practical implications of such a tool in endoscopy education include identifying periods of higher perceived exertion among novice endoscopists, facilitating appropriate levels of guidance from trainers.

Assessing the impact of biomedical research in academic institutions of disparate sizes

PubMed Central

2009-01-01

Background The evaluation of academic research performance is nowadays a priority issue. Bibliometric indicators such as the number of publications, total citation counts and h-index are an indispensable tool in this task but their inherent association with the size of the research output may result in rewarding high production when evaluating institutions of disparate sizes. The aim of this study is to propose an indicator that may facilitate the comparison of institutions of disparate sizes. Methods The Modified Impact Index (MII) was defined as the ratio of the observed h-index (h) of an institution over the h-index anticipated for that institution on average, given the number of publications (N) it produces i.e. (α and β denote the intercept and the slope, respectively, of the line describing the dependence of the h-index on the number of publications in log10 scale). MII values higher than 1 indicate that an institution performs better than the average, in terms of its h-index. Data on scientific papers published during 2002–2006 and within 36 medical fields for 219 Academic Medical Institutions from 16 European countries were used to estimate α and β and to calculate the MII of their total and field-specific production. Results From our biomedical research data, the slope β governing the dependence of h-index on the number of publications in biomedical research was found to be similar to that estimated in other disciplines (≈0.4). The MII was positively associated with the average number of citations/publication (r = 0.653, p < 0.001), the h-index (r = 0.213, p = 0.002), the number of publications with ≥ 100 citations (r = 0.211, p = 0.004) but not with the number of publications (r = -0.020, p = 0.765). It was the most highly associated indicator with the share of country-specific government budget appropriations or outlays for research and development as % of GDP in 2004 (r = 0.229) followed by the average number of citations/publication (r = 0.153) whereas the corresponding correlation coefficient for the h-index was close to 0 (r = 0.029). MII was calculated for first 10 top-ranked European universities in life sciences and biomedicine, as provided by Times Higher Education ranking system, and their total and field-specific performance was compared. Conclusion The MII should complement the use of h-index when comparing the research output of institutions of disparate sizes. It has a conceptual interpretation and, with the data provided here, can be computed for the total research output as well as for field-specific publication sets of institutions in biomedicine. PMID:19480665

Assessing the impact of biomedical research in academic institutions of disparate sizes.

PubMed

Sypsa, Vana; Hatzakis, Angelos

2009-05-29

The evaluation of academic research performance is nowadays a priority issue. Bibliometric indicators such as the number of publications, total citation counts and h-index are an indispensable tool in this task but their inherent association with the size of the research output may result in rewarding high production when evaluating institutions of disparate sizes. The aim of this study is to propose an indicator that may facilitate the comparison of institutions of disparate sizes. The Modified Impact Index (MII) was defined as the ratio of the observed h-index (h) of an institution over the h-index anticipated for that institution on average, given the number of publications (N) it produces i.e. MII = h/10alphaNbeta (alpha and beta denote the intercept and the slope, respectively, of the line describing the dependence of the h-index on the number of publications in log10 scale). MII values higher than 1 indicate that an institution performs better than the average, in terms of its h-index. Data on scientific papers published during 2002-2006 and within 36 medical fields for 219 Academic Medical Institutions from 16 European countries were used to estimate alpha and beta and to calculate the MII of their total and field-specific production. From our biomedical research data, the slope beta governing the dependence of h-index on the number of publications in biomedical research was found to be similar to that estimated in other disciplines ( approximately 0.4). The MII was positively associated with the average number of citations/publication (r = 0.653, p < 0.001), the h-index (r = 0.213, p = 0.002), the number of publications with > or = 100 citations (r = 0.211, p = 0.004) but not with the number of publications (r = -0.020, p = 0.765). It was the most highly associated indicator with the share of country-specific government budget appropriations or outlays for research and development as % of GDP in 2004 (r = 0.229) followed by the average number of citations/publication (r = 0.153) whereas the corresponding correlation coefficient for the h-index was close to 0 (r = 0.029). MII was calculated for first 10 top-ranked European universities in life sciences and biomedicine, as provided by Times Higher Education ranking system, and their total and field-specific performance was compared. The MII should complement the use of h-index when comparing the research output of institutions of disparate sizes. It has a conceptual interpretation and, with the data provided here, can be computed for the total research output as well as for field-specific publication sets of institutions in biomedicine.

A Comparison of Objective Physical Performance Tests and Future Mortality in the Elderly People.

PubMed

Veronese, Nicola; Stubbs, Brendon; Fontana, Luigi; Trevisan, Caterina; Bolzetta, Francesco; Rui, Marina De; Sartori, Leonardo; Musacchio, Estella; Zambon, Sabina; Maggi, Stefania; Perissinotto, Egle; Corti, Maria Chiara; Crepaldi, Gaetano; Manzato, Enzo; Sergi, Giuseppe

2017-03-01

Physical performance is an important predictor of mortality, but little is known on the comparative prognostic utility of different objective physical performance tests in community-dwelling older adults. We compared the prognostic usefulness of several objective physical performance tests on mortality, adjusting our analyses for potential confounders. Among 3,099 older community-dwelling participants included in the Progetto Veneto Anziani study, 2,096 were followed for a mean of 4.4 years. Physical performance tests measured were Short Physical Performance Battery (SPPB), 4-meter gait speed, chair stands time, leg extension and flexion, handgrip strength, and 6-Minute Walking Test (6MWT), treated as continuous variables and categorized in gender-specific quartiles. The main outcome was mortality assessed with death certificates. Participants who died during the follow-up (n = 327) scored significantly worse in all physical performance tests measured at baseline than those who survived (n = 1,769). Using a Harrell's C-index, the highest C-index was observed for 6MWT in men (C-index = 0.735; 95% confidence interval [CI]: 0.701-0.770, p < .0001) and SPPB in women (C-index = 0.781; 95% CI: 0.740-0.822, p = .0009). However, in both genders, only SPPB, 4-meter walking speed, and 6MWT are significant predictors of mortality. Analyses using sex-specific quartiles substantially confirmed these findings. Slow gait speed, 6MWT, and SPPB are significant predictors for mortality in community-dwelling older men and women. Physicians should consider using these tests to identify elderly individuals who are at higher risk of death to improve clinical decision making. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Unidirectional transmission using array of zero-refractive-index metamaterials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fu, Yangyang; Xu, Lin; Hong Hang, Zhi

2014-05-12

In this Letter, we find that high efficient unidirectional transmission occurs for an array of prisms made of zero-refractive-index metamaterials. As a specific demonstration, we further design the device using Dirac-cone-like photonic crystals. The device can function for a broadband of spectrum. Numerical simulations are performed to verify the one-way wave functionality.

The potential benefits of location-specific biometeorological indexes

NASA Astrophysics Data System (ADS)

Wong, Ho Ting; Wang, Jinfeng; Yin, Qian; Chen, Si; Lai, Poh Chin

2017-09-01

It is becoming popular to use biometeorological indexes to study the effects of weather on human health. Most of the biometeorological indexes were developed decades ago and only applicable to certain locations because of different climate types. Merely using standard biometeorological indexes to replace typical weather factors in biometeorological studies of different locations may not be an ideal research direction. This research is aimed at assessing the difference of statistical power between using standard biometeorological indexes and typical weather factors on describing the effects of extreme weather conditions on daily ambulance demands in Hong Kong. Results showed that net effective temperature and apparent temperature did not perform better than typical weather factors in describing daily ambulance demands in this study. The maximum adj- R 2 improvement was only 0.08, whereas the maximum adj- R 2 deterioration was 0.07. In this study, biometeorological indexes did not perform better than typical weather factors, possibly due to the differences of built environments and lifestyles in different locations and eras. Regarding built environments, the original parameters for calculating the index values may not be applicable to Hong Kong as buildings in Hong Kong are extremely dense and most are equipped with air conditioners. Regarding lifestyles, the parameters, which were set decades ago, may be outdated and not suitable to modern lifestyles as using hand-held electrical fans on the street to help reduce heat stress are popular. Hence, it is ideal to have tailor-made updated location-specific biometeorological indexes to study the effects of weather on human health.

The recomBead Borrelia antibody index, CXCL13 and total IgM index for laboratory diagnosis of Lyme neuroborreliosis in children.

PubMed

Skogman, B H; Lager, M; Henningsson, A J; Tjernberg, I

2017-11-01

For laboratory diagnostics of Lyme neuroborreliosis (LNB), the recomBead Borrelia antibody index (AI) assay has shown promising results in a mixed age population, but has not previously been evaluated with specific focus on paediatric patients. The aim of the study was to evaluate the recomBead Borrelia AI assay in cerebrospinal fluid (CSF) for the laboratory diagnosis of LNB in children. We also wanted to explore whether early markers, such as CXCL13 in CSF and/or total IgM index could be useful as complementary diagnostic tools. Children being evaluated for LNB in a Swedish Lyme endemic area were included in the study (n = 146). Serum and CSF were collected on admission. Patients with other specific diagnoses were controls (n = 15). The recomBead Borrelia AI assay and the recomBead CXCL13 assay (Mikrogen) were applied together with total IgM index. The overall sensitivity for recomBead Borrelia AI (IgM and IgG together) was 74% and the specificity was 97%. However, the highest sensitivity (91%) at an acceptable level of specificity (90%) was obtained by recomBead Borrelia AI together with CXCL13 and total IgM index, showing a positive predictive value of 84% and a negative predictive value of 95%. Thus, the recomBead Borrelia AI assay performs with moderate sensitivity and high specificity in paediatric LNB patients. The major advantage seems to be increased sensitivity in the possible LNB group compared to the IDEIA assay. The diagnostic sensitivity may be further increased by using a combination of early markers, such as CXCL13 in CSF and total IgM index.

Method for indexing and retrieving manufacturing-specific digital imagery based on image content

DOEpatents

Ferrell, Regina K.; Karnowski, Thomas P.; Tobin, Jr., Kenneth W.

2004-06-15

A method for indexing and retrieving manufacturing-specific digital images based on image content comprises three steps. First, at least one feature vector can be extracted from a manufacturing-specific digital image stored in an image database. In particular, each extracted feature vector corresponds to a particular characteristic of the manufacturing-specific digital image, for instance, a digital image modality and overall characteristic, a substrate/background characteristic, and an anomaly/defect characteristic. Notably, the extracting step includes generating a defect mask using a detection process. Second, using an unsupervised clustering method, each extracted feature vector can be indexed in a hierarchical search tree. Third, a manufacturing-specific digital image associated with a feature vector stored in the hierarchicial search tree can be retrieved, wherein the manufacturing-specific digital image has image content comparably related to the image content of the query image. More particularly, can include two data reductions, the first performed based upon a query vector extracted from a query image. Subsequently, a user can select relevant images resulting from the first data reduction. From the selection, a prototype vector can be calculated, from which a second-level data reduction can be performed. The second-level data reduction can result in a subset of feature vectors comparable to the prototype vector, and further comparable to the query vector. An additional fourth step can include managing the hierarchical search tree by substituting a vector average for several redundant feature vectors encapsulated by nodes in the hierarchical search tree.

A comparison of four embedded validity indices for the RBANS in a memory disorders clinic.

PubMed

Paulson, Daniel; Horner, Michael David; Bachman, David

2015-05-01

This examination of four embedded validity indices for the Repeated Battery for the Assessment of Neuropsychological Status (RBANS) explores the potential utility of integrating cognitive and self-reported depressive measures. Examined indices include the proposed RBANS Performance Validity Index (RBANS PVI) and the Charleston Revised Index of Effort for the RBANS (CRIER). The CRIER represented the novel integration of cognitive test performance and depression self-report information. The sample included 234 patients without dementia who could be identified as having demonstrated either valid or invalid responding, based on standardized criteria. Sensitivity and specificity for invalid responding varied widely, with the CRIER emerging as the best all-around index (sensitivity = 0.84, specificity = 0.90, AUC = 0.94). Findings support the use of embedded response validity indices, and suggest that the integration of cognitive and self-report depression data may optimize detection of invalid responding among older Veterans. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Measurement of refractive index of hemoglobin in the visible/NIR spectral range

NASA Astrophysics Data System (ADS)

Lazareva, Ekaterina N.; Tuchin, Valery V.

2018-03-01

This study is focused on the measurements of the refractive index of hemoglobin solutions in the visible/near-infrared (NIR) spectral range at room temperature for characteristic laser wavelengths: 480, 486, 546, 589, 644, 656, 680, 930, 1100, 1300, and 1550 nm. Measurements were performed using the multiwavelength Abbe refractometer. Aqua hemoglobin solutions of different concentrations obtained from human whole blood were investigated. The specific increment of refractive index on hemoglobin concentration and the Sellmeier coefficients were calculated.

Validation of nomograms for overall survival, cancer-specific survival, and recurrence in carcinoma of the major salivary glands.

PubMed

Hay, Ashley; Migliacci, Jocelyn; Zanoni, Daniella Karassawa; Patel, Snehal; Yu, Changhong; Kattan, Michael W; Ganly, Ian

2018-05-01

The purpose of this study was to investigate the performance of the Memorial Sloan Kettering Cancer Center salivary carcinoma nomograms predicting overall survival, cancer-specific survival, and recurrence with an external validation dataset. The validation dataset comprised 123 patients treated between 2010 and 2015 at our institution. They were evaluated by assessing discrimination (concordance index [C-index]) and calibration (plotting predicted vs actual probabilities for quintiles). The validation cohort (n = 123) showed some differences to the original cohort (n = 301). The validation cohort had less high-grade cancers (P = .006), less lymphovascular invasion (LVI; P < .001) and shorter follow-up of 19 months versus 45.6 months. Validation showed a C-index of 0.833 (95% confidence interval [CI] 0.758-0.908), 0.807 (95% CI 0.717-0.898), and 0.844 (95% CI 0.768-0.920) for overall survival, cancer-specific survival, and recurrence, respectively. The 3 salivary gland nomograms performed well using a contemporary validation dataset, despite limitations related to sample size, follow-up, and differences in clinical and pathology characteristics between the original and validation cohorts. © 2018 Wiley Periodicals, Inc.

CD64 Index Provides Simple and Predictive Testing for Detection and Monitoring of Sepsis and Bacterial Infection in Hospital Patients ▿ †

PubMed Central

Icardi, M.; Erickson, Y.; Kilborn, S.; Stewart, B.; Grief, B.; Scharnweber, G.

2009-01-01

The rapid diagnosis and management of bacterial infection are heavily dependent upon clinical assessment. Blood culture may take up to 2 days for results and may be suspect. Surface neutrophil CD64 expression has been shown to be upregulated in cases of bacterial infection. Recently, a standardized kit for the CD64 index was used in neonatal intensive care units, showing high sensitivity and specificity for bacterial infections. Our study was designed to confirm and extend these results to adult hospital patients and to determine the impact of this testing on a clinical laboratory's finances and staffing. CD64 indices were performed with peripheral blood drawn in tandem with blood cultures from 109 patients over a 2-month period. We found that a CD64 index of ≤1.19 was predictive of “no growth” blood culture results. An index of >1.19 was predictive of an ultimate clinical and/or culture diagnosis of infection with a sensitivity and specificity of 94.6% and 88.7%, respectively. Positive and negative predictive values were 89.8% and 94%, respectively. The CD64 index was easily performed using our flow cytometer and staff, producing minimal alteration in clinical workflow. A 7-day-a-week testing schedule will result in some additional expense but will be more than offset by the expected cost savings. The CD64 index is a useful and inexpensive test for improving the diagnosis and management of hospital patients with bacterial infection. It can be readily performed by clinical laboratories and could result in considerable savings for the institution. PMID:19846647

[Use of [-2] pro PSA and phi index for early detection of prostate cancer: a prospective of 452 patients].

PubMed

Houlgatte, A; Vincendeau, S; Desfemmes, F; Ramirez, J; Benoist, N; Bensalah, K; Durand, X

2012-05-01

Early detection of prostate cancer (Pca) is a real challenge to reduce morbidity and mortality while avoiding over-diagnosis and over-treatment. The prostate specific antigen (PSA) is characterized by its imperfections justifying the evaluation of new serum or urinary specific markers allowing a better selection of patients at risk of developing aggressive Pca. To compare the value of -2pro PSA and phi index to total and free PSA. Serum sampled from 452 patients from two university centers were used to determine levels of PSA before performing biopsies. The patients were included in this study based on the PSA serum concentration between 1.6 ng/mL and 8 ng/mL according to the WHO international standard. All biopsies were performed according to a standardized protocol consisting of 12 cores or more. Sera were analyzed centrally in one of the two institutions with on a single analyzer. Sera from 243 prostate cancer and 208 negative biopsies patients have been taken into account. Sera were analyzed blinded for total PSA, free PSA and [-2] proPSA using Access(®) immunoassay method from Beckman Coulter. The Prostate Health Index (phi) was calculated using the formula phi=([-2] proPSA/fPSA)×sqrt (PSA). The median value of the phi index is significantly (P>0.0001) higher for patients with cancer (phi=65.8) compared to patients with negative biopsies (phi=40.6). At a given sensitivity, the phi index significantly increases the specificity of detection of prostate cancer compared to other markers. The phi index currently appears as the best predictor of prostate cancer for patients with a total PSA between 1.6 and 8 ng/mL according to the WHO standard. The improvement in specificity of the phi index over tPSA could reduce significantly the numbers of unnecessary biopsies. Whether this new biomarker could be an indicator of aggressive prostate cancer remains to be confirmed. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

An Introduction to a Head and Neck Cancer-Specific Frailty Index and Its Clinical Implications in Elderly Patients: A Prospective Observational Study Focusing on Respiratory and Swallowing Functions

PubMed Central

Kwon, Minsu; Kim, Shin-Ae; Lee, Sang-Wook; Kim, Sung-Bae; Choi, Seung-Ho; Nam, Soon Yuhl; Kim, Sang Yoon

2016-01-01

Introduction. Frailty refers to a decreased physiologic reserve in geriatric patients and its importance in terms of treatment planning and outcome prediction has been emphasized in oncologic practices for older patients with cancer. We investigated the clinical implications of a head and neck cancer (HNC)-specific frailty index suggested by prospective clinical and functional evaluations of HNC patients. Materials and Methods. We analyzed data on 165 elderly patients with HNC who were prospectively enrolled in our hospital from 2010 to 2013. Pretreatment functional evaluations were performed according to all comprehensive geriatric assessment (CGA) domains. We additionally evaluated the patients’ respiratory and swallowing functions using pulmonary function tests, voice handicap index (VHI), MD Anderson Dysphagia Inventory (MDADI), and other associated tests. Factors affecting the 2-year morbidity and mortality were also analyzed. Results. Respiratory and swallowing problems were major causes of 2-year morbidity. Pretreatment performance status, VHI ≥8, MDADI <70, dental problems, and chemotherapy were significantly associated with early morbidity and mortality (all p < .05). CGA-assessed frailty was found in 72 patients (43.6%) and was significantly associated with 2-year mortality (p = .027) but not with morbidity (p = .716). The high-risk group according to our new HNC-specific frailty index that included functional evaluations of respiration and swallowing showed significantly higher 2-year morbidity (p = .043) and mortality (p < .001). Conclusion. Pretreatment functional disabilities related to respiration and swallowing were significantly associated with early morbidity and mortality. The suggested index would be more useful for assessing frailty in elderly HNC patients. Implications for Practice: This study is the first report in terms of suggesting a new frailty index focusing on respiratory and swallowing functions in elderly patients with head and neck cancer. This study shows that functional disabilities associated with respiration and swallowing significantly affected early morbidity and mortality in these elderly patients. The head and neck cancer-specific frailty index described in this report, which includes functional evaluations of respiration and swallowing, significantly predicted both early morbidity and mortality. PMID:27368883

MPEG-7 audio-visual indexing test-bed for video retrieval

NASA Astrophysics Data System (ADS)

Gagnon, Langis; Foucher, Samuel; Gouaillier, Valerie; Brun, Christelle; Brousseau, Julie; Boulianne, Gilles; Osterrath, Frederic; Chapdelaine, Claude; Dutrisac, Julie; St-Onge, Francis; Champagne, Benoit; Lu, Xiaojian

2003-12-01

This paper reports on the development status of a Multimedia Asset Management (MAM) test-bed for content-based indexing and retrieval of audio-visual documents within the MPEG-7 standard. The project, called "MPEG-7 Audio-Visual Document Indexing System" (MADIS), specifically targets the indexing and retrieval of video shots and key frames from documentary film archives, based on audio-visual content like face recognition, motion activity, speech recognition and semantic clustering. The MPEG-7/XML encoding of the film database is done off-line. The description decomposition is based on a temporal decomposition into visual segments (shots), key frames and audio/speech sub-segments. The visible outcome will be a web site that allows video retrieval using a proprietary XQuery-based search engine and accessible to members at the Canadian National Film Board (NFB) Cineroute site. For example, end-user will be able to ask to point on movie shots in the database that have been produced in a specific year, that contain the face of a specific actor who tells a specific word and in which there is no motion activity. Video streaming is performed over the high bandwidth CA*net network deployed by CANARIE, a public Canadian Internet development organization.

KWOC (Key-Word-Out-of-Context) Index of US Nuclear Regulatory Commission Regulatory Guide Series

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jennings, S.D.

1990-04-01

To meet the objectives of the program funded by the Department of Energy (DOE)-Nuclear Energy (NE) Technology Support Programs, the Performance Assurance Project Office (PAPO) administers a Performance Assurance Information Program that collects, compiles, and distributes program-related information, reports, and publications for the benefit of the DOE-NE program participants. THE KWOC Index of US Nuclear Regulatory Commission Regulatory Guide Series'' is prepared as an aid in searching for specific topics in the US Nuclear Regulatory Commission, Regulatory Guide Series.

Effect of different warm-up procedures on the performance of resistance training exercises.

PubMed

Ribeiro, Alex S; Romanzini, Marcelo; Schoenfeld, Brad J; Souza, Mariana F; Avelar, Ademar; Cyrino, Edilson S

2014-08-01

Warm-up has been shown to mediate numerous acute physiological alterations that have been purported to confer beneficial effects on performance. This study investigated the acute effects of different warm-up procedures on resistance training performance. Employing a randomized, counterbalanced crossover design, 15 men performed 3 exercises (4 sets of bench press, squat, and arm curl at 80% of 1RM) to failure in 4 conditions (control, specific, aerobic, and combined). Outcome measures included the sum of repetitions and a fatigue index measuring the decline between sets. There was no significant difference for the sum of repetitions or for fatigue index among conditions for the 3 exercises. Performance in the resistance training exercises was not influenced by warm-up.

Multiparametric ultrasonography and ultrasound elastography in the differentiation of parathyroid lesions from ectopic thyroid lesions or lymphadenopathies.

PubMed

Isidori, Andrea M; Cantisani, Vito; Giannetta, Elisa; Diacinti, Daniele; David, Emanuele; Forte, Valerio; Elia, Daniela; De Vito, Corrado; Sbardella, Emilia; Gianfrilli, Daniele; Monteleone, Francesco; Pepe, Jessica; Minisola, Salvatore; Ascenti, Giorgio; D'Andrea, Vito; Catalano, Carlo; D'Ambrosio, Ferdinando

2017-08-01

To evaluate the accuracy of ultrasound elastography with Elastoscan TM Core Index in the differential diagnosis of parathyroid lesions from ectopic thyroid nodules and lymph nodes. Seventy nine patients with repeatedly high levels of circulating intact parathyroid hormone, normal vitamin D and renal function tests, with an ultrasound scan showing a neck lesion, sharply demarcated from the thyroid lobules, were consecutively enrolled. Ultrasound with and without Color Doppler and ultrasound elastography were performed before histological examination. All ultrasound features, vascularization and ultrasound elastography diagnostic performance were assessed using ROC curves. Histological examination confirmed 47 parathyroid lesions, 18 thyroid ectopic nodules and 14 reactive lymph nodes. In distinguishing parathyroid from thyroid nodules, shape had a 100 % sensitivity (95 % CI 92.4-100) and 50 % specificity (95 % CI 37.2-64.7), cleavage had a 85.1 % sensitivity (95 % CI 72.3-92.6) and 77.8 % specificity (95 % CI 65.1-88) while peripheral vascularization had a sensitivity of 91.5 (95 % CI 79.6-97.6) and specificity of 72.2 (95 % CI 46.5-90.3). An Elastoscan TM Core Indexof 1.28 was 46 % sensitive (95 % CI 33.4-58.7) and 77 % specific (95 % CI 66.2-89.1) in discriminating parathyroid lesions from thyroid nodules. An Elastoscan TM Core Index of 1.0 was 78 % sensitive (95 % CI 65.1-88) and 71 % specific (95 % CI 56-81.3) in discriminating parathyroid lesions from lymph nodes (p = 0.045). An Elastoscan TM Core Index greater than 2.58 had a 100 % sensitivity (95 % CI 43.8-100) and 95.4 % specificity (95 % CI 38.3-99.7) in discriminating malignant from benign parathyroid nodules. Elastoscan TM Core Index was significantly higher in thyroid nodules than in reactive lymph nodes (1.18 ± 0.62, p = 0.008). The ultrasound features of cleavage and peripheral vascularization help to differentiate parathyroid from thyroid nodules. Elastoscan TM Core Index can improve ultrasound discrimination of parathyroid lesions from lymph nodes. The Elastoscan TM Core Index is significantly higher in malignant than in benign parathyroid lesions.

Performance determinants of fixed gear cycling during criteriums.

PubMed

Babault, Nicolas; Poisson, Maxime; Cimadoro, Guiseppe; Cometti, Carole; Païzis, Christos

2018-06-17

Nowadays, fixed gear competitions on outdoor circuits such as criteriums are regularly organized worldwide. To date, no study has investigated this alternative form of cycling. The purpose of the present study was to examine fixed gear performance indexes and to characterize physiological determinants of fixed gear cyclists. This study was carried out in two parts. Part 1 (n = 36) examined correlations between performance indexes obtained during a real fixed gear criterium (time trial, fastest laps, averaged lap time during races, fatigue indexes) and during a sprint track time trial. Part 2 (n = 9) examined correlations between the recorded performance indexes and some aerobic and anaerobic performance outputs (VO 2max , maximal aerobic power, knee extensor and knee flexor maximal voluntary torque, vertical jump height and performance during a modified Wingate test). Results from Part 1 indicated significant correlations between fixed gear final performance (i.e. average lap time during the finals) and single lap time (time trial, fastest lap during races and sprint track time trial). In addition, results from Part 2 revealed significant correlations between fixed gear performance and aerobic indicators (VO 2max and maximal aerobic power). However, no significant relationship was obtained between fixed gear cycling and anaerobic qualities such as strength. Similarly to traditional cycling disciplines, we concluded that fixed gear cycling is mainly limited by aerobic capacity, particularly criteriums final performance. However, specific skills including technical competency should be considered.

Performance indicators and decision making for outsourcing public health laboratory services.

PubMed

Santos, Maria Angelica Borges dos; Moraes, Ricardo Montes de; Passos, Sonia Regina Lambert

2012-06-01

To develop performance indicators for outsourcing clinical laboratory services, based on information systems and public administrative records. In the municipality of Rio de Janeiro, Southern Brazil, the public health laboratory network comprised 33 laboratories with automated equipment (but no integrated information system), 90 primary care units (where sample collection was performed) and 983 employees. Information records were obtained from the administrative records of the Budget Information System for Public Health and the Outpatient and Hospital Information System of the Unified Health System. Performance indicators (production, productivity, usage and costs) were generated from data collected routinely from 2006 to 2008. The variations in production, costs and unit prices for tests were analyzed by Laspeyres and Paasche indices, which specifically measure laboratory activity, and by the Consumer Price Index from the Brazilian Institute of Geography and Statistics. A total of 10,359,111 tests were performed in 2008 (10.6% increase over 2006), and the test/employee ratio grew by 8.6%. The costs of supplies, wages and providers increased by 2.3%, 45.4% and 18.3%, respectively. The laboratory tests per visit and hospitalizations increased by 10% and 20%, respectively. The direct costs totaled R$ 63.2 million in 2008, representing an increase of 22.2% in current values during the period analyzed. The direct costs deflated by the Brazilian National Consumer Price Index (9.5% for the period) showed an 11.6% increase in production volumes. The activity-specific volume index, which considers changes in the mix of tests, showed increases of 18.5% in the test price and 3.1% in the production volume. The performance indicators, particularly the specific indices for volume and price of activity, constitute a baseline of performance potential for monitoring private laboratories and contractors. The economic performance indicators demonstrated the need for network information system integration prior to an outsourcing decision.

Validation of Ten Noninvasive Diagnostic Models for Prediction of Liver Fibrosis in Patients with Chronic Hepatitis B

PubMed Central

Cheng, Jieyao; Hou, Jinlin; Ding, Huiguo; Chen, Guofeng; Xie, Qing; Wang, Yuming; Zeng, Minde; Ou, Xiaojuan; Ma, Hong; Jia, Jidong

2015-01-01

Background and Aims Noninvasive models have been developed for fibrosis assessment in patients with chronic hepatitis B. However, the sensitivity, specificity and diagnostic accuracy in evaluating liver fibrosis of these methods have not been validated and compared in the same group of patients. The aim of this study was to verify the diagnostic performance and reproducibility of ten reported noninvasive models in a large cohort of Asian CHB patients. Methods The diagnostic performance of ten noninvasive models (HALF index, FibroScan, S index, Zeng model, Youyi model, Hui model, APAG, APRI, FIB-4 and FibroTest) was assessed against the liver histology by ROC curve analysis in CHB patients. The reproducibility of the ten models were evaluated by recalculating the diagnostic values at the given cut-off values defined by the original studies. Results Six models (HALF index, FibroScan, Zeng model, Youyi model, S index and FibroTest) had AUROCs higher than 0.70 in predicting any fibrosis stage and 2 of them had best diagnostic performance with AUROCs to predict F≥2, F≥3 and F4 being 0.83, 0.89 and 0.89 for HALF index, 0.82, 0.87 and 0.87 for FibroScan, respectively. Four models (HALF index, FibroScan, Zeng model and Youyi model) showed good diagnostic values at given cut-offs. Conclusions HALF index, FibroScan, Zeng model, Youyi model, S index and FibroTest show a good diagnostic performance and all of them, except S index and FibroTest, have good reproducibility for evaluating liver fibrosis in CHB patients. Registration Number ChiCTR-DCS-07000039. PMID:26709706

The imperative of culture: a quantitative analysis of the impact of culture on workforce engagement, patient experience, physician engagement, value-based purchasing, and turnover.

PubMed

Owens, Katie; Eggers, Jim; Keller, Stephanie; McDonald, Audrey

2017-01-01

Current uncertainty for the future of the health care landscape is placing an increasing amount of pressure on leadership teams to be prepared to steer their organization forward in a number of potential directions. It is commonly recognized among health care leaders that culture will either enable or disable organizational success. However, very few studies empirically link culture to health care-specific performance outcomes. Nearly every health care organization in the US specifies its cultural aspirations through mission and vision statements and values. Ambitions of patient-centeredness, care for the community, workplace of choice, and world-class quality are frequently cited; yet, little definitive research exists to quantify the importance of building high-performing cultures. Our study examined the impact of cultural attributes defined by a culture index (Cronbach's alpha = 0.88) on corresponding performance with key health care measures. We mapped results of the culture index across data sets, compared results, and evaluated variations in performance among key indicators for leaders. Organizations that perform in the top quartile for our culture index statistically significantly outperformed those in the bottom quartile on all but one key performance indicator tested. The culture top quartile organizations outperformed every domain for employee engagement, physician engagement, patient experience, and overall value-based purchasing performance with statistical significance. Culture index top quartile performers also had a 3.4% lower turnover rate than the bottom quartile performers. Finally, culture index top quartile performers earned an additional 1% on value-based purchasing. Our findings demonstrate a meaningful connection between performance in the culture index and organizational performance. To best impact these key performance outcomes, health care leaders should pay attention to culture and actively steer workforce engagement in attributes that represent the culture index, such as treating patients as valued customers, having congruency between employee and organizational values, promoting employee pride, and encouraging the feeling that being a member of the organization is rewarding, in order to leverage culture as a competitive advantage.

The imperative of culture: a quantitative analysis of the impact of culture on workforce engagement, patient experience, physician engagement, value-based purchasing, and turnover

PubMed Central

Owens, Katie; Eggers, Jim; Keller, Stephanie; McDonald, Audrey

2017-01-01

Current uncertainty for the future of the health care landscape is placing an increasing amount of pressure on leadership teams to be prepared to steer their organization forward in a number of potential directions. It is commonly recognized among health care leaders that culture will either enable or disable organizational success. However, very few studies empirically link culture to health care-specific performance outcomes. Nearly every health care organization in the US specifies its cultural aspirations through mission and vision statements and values. Ambitions of patient-centeredness, care for the community, workplace of choice, and world-class quality are frequently cited; yet, little definitive research exists to quantify the importance of building high-performing cultures. Our study examined the impact of cultural attributes defined by a culture index (Cronbach’s alpha = 0.88) on corresponding performance with key health care measures. We mapped results of the culture index across data sets, compared results, and evaluated variations in performance among key indicators for leaders. Organizations that perform in the top quartile for our culture index statistically significantly outperformed those in the bottom quartile on all but one key performance indicator tested. The culture top quartile organizations outperformed every domain for employee engagement, physician engagement, patient experience, and overall value-based purchasing performance with statistical significance. Culture index top quartile performers also had a 3.4% lower turnover rate than the bottom quartile performers. Finally, culture index top quartile performers earned an additional 1% on value-based purchasing. Our findings demonstrate a meaningful connection between performance in the culture index and organizational performance. To best impact these key performance outcomes, health care leaders should pay attention to culture and actively steer workforce engagement in attributes that represent the culture index, such as treating patients as valued customers, having congruency between employee and organizational values, promoting employee pride, and encouraging the feeling that being a member of the organization is rewarding, in order to leverage culture as a competitive advantage. PMID:29355220

A bottom-up approach to MEDLINE indexing recommendations.

PubMed

Jimeno-Yepes, Antonio; Wilkowski, Bartłomiej; Mork, James G; Van Lenten, Elizabeth; Fushman, Dina Demner; Aronson, Alan R

2011-01-01

MEDLINE indexing performed by the US National Library of Medicine staff describes the essence of a biomedical publication in about 14 Medical Subject Headings (MeSH). Since 2002, this task is assisted by the Medical Text Indexer (MTI) program. We present a bottom-up approach to MEDLINE indexing in which the abstract is searched for indicators for a specific MeSH recommendation in a two-step process. Supervised machine learning combined with triage rules improves sensitivity of recommendations while keeping the number of recommended terms relatively small. Improvement in recommendations observed in this work warrants further exploration of this approach to MTI recommendations on a larger set of MeSH headings.

Measurement of refractive index of hemoglobin in the visible/NIR spectral range.

PubMed

Lazareva, Ekaterina N; Tuchin, Valery V

2018-03-01

This study is focused on the measurements of the refractive index of hemoglobin solutions in the visible/near-infrared (NIR) spectral range at room temperature for characteristic laser wavelengths: 480, 486, 546, 589, 644, 656, 680, 930, 1100, 1300, and 1550 nm. Measurements were performed using the multiwavelength Abbe refractometer. Aqua hemoglobin solutions of different concentrations obtained from human whole blood were investigated. The specific increment of refractive index on hemoglobin concentration and the Sellmeier coefficients were calculated. (2018) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE).

The product of triglycerides and glucose, a simple measure of insulin sensitivity. Comparison with the euglycemic-hyperinsulinemic clamp.

PubMed

Guerrero-Romero, Fernando; Simental-Mendía, Luis E; González-Ortiz, Manuel; Martínez-Abundis, Esperanza; Ramos-Zavala, María G; Hernández-González, Sandra O; Jacques-Camarena, Omar; Rodríguez-Morán, Martha

2010-07-01

To meet the worldwide challenge of emerging diabetes, accessible and inexpensive tests to identify insulin resistance are needed. To evaluate the sensitivity and specificity of the product of fasting, we compared the triglycerides and glucose (TyG) index, a simple measure of insulin resistance, with the euglycemic-hyperinsulinemic clamp test. We conducted a cross-sectional study of the general population and outpatients of the Internal Medicine Department at the Medical Unit of High Specialty of the Specialty Hospital at the West National Medical Center in Guadalajara, Mexico. Eleven nonobese healthy subjects, 34 obese normal glucose tolerance individuals, 22 subjects with prediabetes, and 32 diabetic patients participated in the study. We performed a euglycemic-hyperinsulinemic clamp test. Sensitivity and specificity of the TyG index [Ln(fasting triglycerides) (mg/dl) x fasting glucose (mg/dl)/2] were measured, as well as the area under the curve of the receiver operating characteristic scatter plot and the correlation between the TyG index and the total glucose metabolism (M) rates. Pearson's correlation coefficient between the TyG index and M rates was -0.681 (P < 0.005). Correlation between the TyG index and M rates was similar between men (-0.740) and women (-0.730), nonobese (-0.705) and obese (-0.710), and nondiabetic (-0.670) and diabetic (-0.690) individuals. The best value of the TyG index for diagnosis of insulin resistance was 4.68, which showed the highest sensitivity (96.5%) and specificity (85.0%; area under the curve + 0.858). The TyG index has high sensitivity and specificity, suggesting that it could be useful for identification of subjects with decreased insulin sensitivity.

The heat rate index indicator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lasasso, M.; Runyan, B.; Napoli, J.

1995-06-01

This paper describes a method of tracking unit performance through the use of a reference number called the Heat Rate Index Indicator. The ABB Power Plant Controls OTIS performance monitor is used to determine when steady load conditions exist and then to collect controllable and equipment loss data which significantly impact thermal efficiency. By comparing these loss parameters to those found during the previous heat balance, it is possible to develop a new adjusted heat rate curve. These impacts on heat rate are used to changes the shape of the tested heat rate curve by the appropriate percentages over amore » specified load range. Mathcad is used to determine the Heat Rate Index by integrating for the areas beneath the adjusted heat rate curve and a heat rate curve that represents the unit`s ideal heat rate curve is the Heat Rate Index. An index of 1.0 indicates that the unit is operating at an ideal efficiency, while an index of less than 1.0 indicates that the unit is operating at less than ideal conditions. A one per cent change in the Heat Rate Index is equivalent to a one percent change in heat rate. The new shape of the adjusted heat rate curve and the individual curves generated from the controllable and equipment loss parameters are useful for determining performance problems in specific load ranges.« less

A randomized controlled trial of an activity specific exercise program for individuals with Alzheimer disease in long-term care settings.

PubMed

Roach, Kathryn E; Tappen, Ruth M; Kirk-Sanchez, Neva; Williams, Christine L; Loewenstein, David

2011-01-01

To determine whether an activity specific exercise program could improve ability to perform basic mobility activities in long-term care residents with Alzheimer disease (AD). Randomized, controlled, single-blinded clinical trial. Residents of 7 long-term care facilities. Eighty-two long-term care residents with mild to severe AD. An activity specific exercise program was compared to a walking program and to an attention control. Ability to perform bed mobility and transfers was assessed using the subscales of the Acute Care Index of Function; functional mobility was measured using the 6-Minute Walk test. Subjects receiving the activity specific exercise program improved in ability to perform transfers, whereas subjects in the other 2 groups declined.

[Simultaneous determination of five main index components and specific chromatograms analysis in Xiaochaihu granules].

PubMed

Zhuang, Yan-Shuang; Cai, Hao; Liu, Xiao; Cai, Bao-Chang

2012-01-01

Reversed phase high performance liquid chromatography with diode array detector was employed for simultaneous determination of five main index components and specific chromatograms analysis in Xiaochaihu granules with a linear gradient elution of acetonitrile-water (containing 0.1% phosphoric acid) as mobile phase. The results showed that five main index components (baicalin, baicalein, wogonoside, wogonin, enoxolone) were separated well under the analytical condition. The linear ranges of five components were 0.518 - 16.576, 0.069 - 2.197, 0.167 - 5.333, 0.009 - 0.297 and 0.006 - 0.270 mg x g(-1), respectively. The correlation coefficients were 0.999 9, and the average recoveries ranged from 95% to 105%. Twelve common peaks were selected as the specific chromatograms of Xiaochaihu granules with baicalin as the reference peak. There were good similarities between the reference and the ten batches of samples. The similarity coefficients were no less than 0.9. The analytical method established is highly sensitive with strong specificity and it can be used efficiently in the quality control of Xiaochaihu granules.

Audiometric asymmetry and tinnitus laterality.

PubMed

Tsai, Betty S; Sweetow, Robert W; Cheung, Steven W

2012-05-01

To identify an optimal audiometric asymmetry index for predicting tinnitus laterality. Retrospective medical record review. Data from adult tinnitus patients (80 men and 44 women) were extracted for demographic, audiometric, tinnitus laterality, and related information. The main measures were sensitivity, specificity, positive predictive value (PPV), and receiver operating characteristic (ROC) curves. Three audiometric asymmetry indices were constructed using one, two, or three frequency elements to compute the average interaural threshold difference (aITD). Tinnitus laterality predictive performance of a particular index was assessed by increasing the cutoff or minimum magnitude of the aITD from 10 to 35 dB in 5-dB steps to determine its ROC curve. Single frequency index performance was inferior to the other two (P < .05). Double and triple frequency indices were indistinguishable (P > .05). Two adjoining frequency elements with aITD ≥ 15 dB performed optimally for predicting tinnitus laterality (sensitivity = 0.59, specificity = 0.71, and PPV = 0.76). Absolute and relative magnitudes of hearing loss in the poorer ear were uncorrelated with tinnitus distress. An optimal audiometric asymmetry index to predict tinnitus laterality is one whereby 15 dB is the minimum aITD of two adjoining frequencies, inclusive of the maximal ITD. Tinnitus laterality dependency on magnitude of interaural asymmetry may inform design and interpretation of neuroimaging studies. Monaural acoustic tinnitus therapy may be an initial consideration for asymmetric hearing loss meeting the criterion of aITD ≥ 15 dB. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Precision, accuracy, cross reactivity and comparability of serum indices measurement on Abbott Architect c8000, Beckman Coulter AU5800 and Roche Cobas 6000 c501 clinical chemistry analyzers.

PubMed

Nikolac Gabaj, Nora; Miler, Marijana; Vrtarić, Alen; Hemar, Marina; Filipi, Petra; Kocijančić, Marija; Šupak Smolčić, Vesna; Ćelap, Ivana; Šimundić, Ana-Maria

2018-04-25

The aim of our study was to perform verification of serum indices on three clinical chemistry platforms. This study was done on three analyzers: Abbott Architect c8000, Beckman Coulter AU5800 (BC) and Roche Cobas 6000 c501. The following analytical specifications were verified: precision (two patient samples), accuracy (sample with the highest concentration of interferent was serially diluted and measured values compared to theoretical values), comparability (120 patients samples) and cross reactivity (samples with increasing concentrations of interferent were divided in two aliquots and remaining interferents were added in each aliquot. Measurements were done before and after adding interferents). Best results for precision were obtained for the H index (0.72%-2.08%). Accuracy for the H index was acceptable for Cobas and BC, while on Architect, deviations in the high concentration range were observed (y=0.02 [0.01-0.07]+1.07 [1.06-1.08]x). All three analyzers showed acceptable results in evaluating accuracy of L index and unacceptable results for I index. The H index was comparable between BC and both, Architect (Cohen's κ [95% CI]=0.795 [0.692-0.898]) and Roche (Cohen's κ [95% CI]=0.825 [0.729-0.922]), while Roche and Architect were not comparable. The I index was not comparable between all analyzer combinations, while the L index was only comparable between Abbott and BC. Cross reactivity analysis mostly showed that serum indices measurement is affected when a combination of interferences is present. There is heterogeneity between analyzers in the hemolysis, icteria, lipemia (HIL) quality performance. Verification of serum indices in routine work is necessary to establish analytical specifications.

Assessing the driving performance of older adult drivers: on-road versus simulated driving.

PubMed

Lee, Hoe C; Cameron, Don; Lee, Andy H

2003-09-01

To validate a laboratory-based driving simulator in measuring on-road driving performance, 129 older adult drivers were assessed with both the simulator and an on-road test. The driving performance of the participants was gauged by appropriate and reliable age-specific assessment criteria, which were found to be negatively correlated with age. Using principal component analysis, two performance indices were developed from the criteria to represent the overall performance in simulated driving and the on-road assessment. There was significant positive association between the two indices, with the simulated driving performance index explaining over two-thirds of the variability of the on-road driving performance index, after adjustment for age and gender of the drivers. The results supported the validity of the driving simulator and it is a safer and more economical method than the on-road testing to assess the driving performance of older adult drivers.

Validation of the National Aeronautics and Space Administration Task Load Index as a tool to evaluate-the learning curve for endoscopy training

PubMed Central

Mohamed, Rachid; Raman, Maitreyi; Anderson, John; McLaughlin, Kevin; Rostom, Alaa; Coderre, Sylvain

2014-01-01

BACKGROUND: Although workplace workload assessments exist in different fields, an endoscopy-specific workload assessment tool is lacking. OBJECTIVE: To validate such a workload tool and use it to map the progression of novice trainees in gastroenterology in performing their first endoscopies. METHODS: The National Aeronautics and Space Administration Task Load Index (NASA-TLX) workload assessment tool was completed by eight novice trainees in gastroenterology and 10 practicing gastroenterologists/surgeons. An exploratory factor analysis was performed to construct a streamlined endoscopy-specific task load index, which was subsequently validated. The ‘Endoscopy Task Load Index’ was used to monitor progression of trainee exertion and self-assessed performance over their first 40 procedures. RESULTS: From the factor analysis of the NASA-TLX, two principal components emerged: a measure of exertion and a measure of self-efficacy. These items became the components of the newly validated Endoscopy Task Load Index. There was a steady decline in self-perceived exertion over the training period, which was more rapid for gastroscopy than colonoscopy. The self-efficacy scores for gastroscopy rapidly increased over the first few procedures, reaching a plateau after this period of time. For colonoscopy, there was a progressive increase in reported self-efficacy over the first three quartiles of procedures, followed by a drop in self-efficacy scores over the final quartile. DISCUSSION: The present study validated an Endoscopy Task Load Index that can be completed in <1 min. Practical implications of such a tool in endoscopy education include identifying periods of higher perceived exertion among novice endoscopists, facilitating appropriate levels of guidance from trainers. PMID:24619638

Validation of a quality-of-life instrument for patients with nonmelanoma skin cancer.

PubMed

Rhee, John S; Matthews, B Alex; Neuburg, Marcy; Logan, Brent R; Burzynski, Mary; Nattinger, Ann B

2006-01-01

To validate a disease-specific quality-of-life instrument--the Skin Cancer Index--intended to measure quality-of-life issues relevant to patients with nonmelanoma skin cancer. Internal reliability, convergent and divergent validity with existing scales, and factor analyses were performed in a cross-sectional study of 211 patients presenting with cervicofacial nonmelanoma skin cancer to a dermatologic surgery clinic. Factor analyses of the Skin Cancer Index confirmed a multidimensional scale with 3 distinct subscales-emotional, social, and appearance. Excellent internal validity of the 3 subscales was demonstrated. Substantial evidence was observed for convergent validity with the Dermatology Life Quality Index, Rosenberg Self-Esteem Scale, Lerman's Cancer Worry Scale, and Medical Outcomes Survey Short-Form 12 domains for vitality, emotion, social function, and mental health. These findings validate a new disease-specific quality-of-life instrument for patients with cervicofacial nonmelanoma skin cancer. Studies on the responsiveness of the Skin Cancer Index to clinical intervention are currently under way.

Non-parametric early seizure detection in an animal model of temporal lobe epilepsy

NASA Astrophysics Data System (ADS)

Talathi, Sachin S.; Hwang, Dong-Uk; Spano, Mark L.; Simonotto, Jennifer; Furman, Michael D.; Myers, Stephen M.; Winters, Jason T.; Ditto, William L.; Carney, Paul R.

2008-03-01

The performance of five non-parametric, univariate seizure detection schemes (embedding delay, Hurst scale, wavelet scale, nonlinear autocorrelation and variance energy) were evaluated as a function of the sampling rate of EEG recordings, the electrode types used for EEG acquisition, and the spatial location of the EEG electrodes in order to determine the applicability of the measures in real-time closed-loop seizure intervention. The criteria chosen for evaluating the performance were high statistical robustness (as determined through the sensitivity and the specificity of a given measure in detecting a seizure) and the lag in seizure detection with respect to the seizure onset time (as determined by visual inspection of the EEG signal by a trained epileptologist). An optimality index was designed to evaluate the overall performance of each measure. For the EEG data recorded with microwire electrode array at a sampling rate of 12 kHz, the wavelet scale measure exhibited better overall performance in terms of its ability to detect a seizure with high optimality index value and high statistics in terms of sensitivity and specificity.

Lateral variation in pavement smoothness

DOT National Transportation Integrated Search

2002-12-01

Current performance-based contracting specifications employ International Roughness Index (IRI) to measure the smoothness of a pavement as perceived by the motorist. This parameter is measured in the outer or right-hand traffic lane and requires an u...

Groundwater vulnerability and risk mapping using GIS, modeling and a fuzzy logic tool.

PubMed

Nobre, R C M; Rotunno Filho, O C; Mansur, W J; Nobre, M M M; Cosenza, C A N

2007-12-07

A groundwater vulnerability and risk mapping assessment, based on a source-pathway-receptor approach, is presented for an urban coastal aquifer in northeastern Brazil. A modified version of the DRASTIC methodology was used to map the intrinsic and specific groundwater vulnerability of a 292 km(2) study area. A fuzzy hierarchy methodology was adopted to evaluate the potential contaminant source index, including diffuse and point sources. Numerical modeling was performed for delineation of well capture zones, using MODFLOW and MODPATH. The integration of these elements provided the mechanism to assess groundwater pollution risks and identify areas that must be prioritized in terms of groundwater monitoring and restriction on use. A groundwater quality index based on nitrate and chloride concentrations was calculated, which had a positive correlation with the specific vulnerability index.

CSF free light chain identification of demyelinating disease: comparison with oligoclonal banding and other CSF indexes.

PubMed

Gurtner, Kari M; Shosha, Eslam; Bryant, Sandra C; Andreguetto, Bruna D; Murray, David L; Pittock, Sean J; Willrich, Maria Alice V

2018-02-19

Cerebrospinal fluid (CSF) used in immunoglobulin gamma (IgG) index testing and oligoclonal bands (OCBs) are common laboratory tests used in the diagnosis of multiple sclerosis. The measurement of CSF free light chains (FLC) could pose as an alternative to the labor-intensive isoelectric-focusing (IEF) gels used for OCBs. A total of 325 residual paired CSF and serum specimens were obtained after physician-ordered OCB IEF testing. CSF kappa (cKFLC) and lambda FLC (cLFLC), albumin and total IgG were measured. Calculations were performed based on combinations of analytes: CSF sum of kappa and lambda ([cKFLC+cLFLC]), kappa-index (K-index) ([cKFLC/sKFLC]/[CSF albumin/serum albumin]), kappa intrathecal fraction (KFLCIF) {([cKFLC/sKFLC]-[0.9358×CSF albumin/serum albumin]^[0.6687×sKFLC]/cKFLC)} and IgG-index ([CSF IgG/CSF albumin]/[serum IgG/serum albumin]). Patients were categorized as: demyelination (n=67), autoimmunity (n=53), non-inflammatory (n=50), inflammation (n=38), degeneration (n=28), peripheral neuropathy (n=24), infection (n=13), cancer (n=11), neuromyelitis optica (n=10) and others (n=31). cKFLC measurement used alone at a cutoff of 0.0611 mg/dL showed >90% agreement to OCBs, similar or better performance than all other calculations, reducing the number of analytes and variables. When cases of demyelinating disease were reviewed, cKFLC measurements showed 86% clinical sensitivity/77% specificity. cKFLC alone demonstrates comparable performance to OCBs along with increased sensitivity for demyelinating diseases. Replacing OCB with cKFLC would alleviate the need for serum and CSF IgG and albumin and calculated conversions. cKFLC can overcome challenges associated with performance, interpretation, and cost of traditional OCBs, reducing costs and maintaining sensitivity and specificity supporting MS diagnosis.

48 CFR 1252.211-70 - Index for specifications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Index for specifications... Index for specifications. As prescribed in (TAR) 48 CFR 1211.204-70, insert the following clause: Index for Specifications (APR 2005) If an index or table of contents is furnished in connection with...

48 CFR 3052.211-70 - Index for specifications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 48 Federal Acquisition Regulations System 7 2010-10-01 2010-10-01 false Index for specifications... CLAUSES Text of Provisions and Clauses 3052.211-70 Index for specifications. As prescribed in (HSAR) 48 CFR 3011.204-70 insert the following clause: Index for Specifications (DEC 2003) If an index or table...

Left Ventricular Isovolumetric Relaxation Time Is Prolonged in Fetal Long-QT Syndrome.

PubMed

Clur, Sally-Ann B; Vink, Arja S; Etheridge, Susan P; Robles de Medina, Pascale G; Rydberg, Annika; Ackerman, Michael J; Wilde, Arthur A; Blom, Nico A; Benson, D Woodrow; Herberg, Ulrike; Donofrio, Mary T; Cuneo, Bettina F

2018-04-01

Long-QT syndrome (LQTS), an inherited cardiac repolarization disorder, is an important cause of fetal and neonatal mortality. Detecting LQTS prenatally is challenging. A fetal heart rate (FHR) less than third percentile for gestational age is specific for LQTS, but the sensitivity is only ≈50%. Left ventricular isovolumetric relaxation time (LVIRT) was evaluated as a potential diagnostic marker for fetal LQTS. LV isovolumetric contraction time, LV ejection time, LVIRT, cycle length, and FHR were measured using pulsed Doppler waveforms in fetuses. Time intervals were expressed as percentages of cycle length, and the LV myocardial performance index was calculated. Single measurements were stratified by gestational age and compared between LQTS fetuses and controls. Receiver-operator curves were performed for FHR and normalized LVIRT (N-LVIRT). A linear mixed-effect model including multiple measurements was used to analyze trends in FHR, N-LVIRT, and LV myocardial performance index. There were 33 LQTS fetuses and 469 controls included. In LQTS fetuses, the LVIRT was prolonged in all gestational age groups ( P <0.001), as was the N-LVIRT. The best cutoff to diagnose LQTS was N-LVIRT ≥11.3 at ≤20 weeks (92% sensitivity, 70% specificity). Simultaneous analysis of N-LVIRT and FHR improved the sensitivity and specificity for LQTS (area under the curve=0.96; 95% confidence interval, 0.82-1.00 at 21-30 weeks). N-LVIRT, LV myocardial performance index, and FHR trends differed significantly between LQTS fetuses and controls through gestation. The LVIRT is prolonged in LQTS fetuses. Findings of a prolonged N-LVIRT and sinus bradycardia can improve the prenatal detection of fetal LQTS. © 2018 American Heart Association, Inc.

The Surgeon Volume-outcome Relationship: Not Yet Ready for Policy.

PubMed

Modrall, J Gregory; Minter, Rebecca M; Minhajuddin, Abu; Eslava-Schmalbach, Javier; Joshi, Girish P; Patel, Shivani; Rosero, Eric B

2018-05-01

Increasing surgeon volume may improve outcomes for index operations. We hypothesized that there may be surrogate operative experiences that yield similar outcomes for surgeons with a low-volume experience with a specific index operation, such as esophagectomy. The relationship between surgeon volume and outcomes has potential implications for credentialing of surgeons. Restrictions of privileges based on surgeon volume are only reasonable if there is no substitute for direct experience with the index operation. This study was aimed at determining whether there are valid surrogates for direct experience with a sample index operation-open esophagectomy. The Nationwide Inpatient Sample (2003-2009) was utilized. Surgeons were stratified into low and high-volume groups based on annual volume of esophagectomy. Surrogate volume was defined as the aggregate annual volume per surgeon of upper gastrointestinal operations including excision of esophageal diverticulum, gastrectomy, gastroduodenectomy, and repair of diaphragmatic hernia. In all, 26,795 esophagectomies were performed nationwide (2003-2009), with a crude inhospital mortality rate of 5.2%. Inhospital mortality decreased with increasing volume of esophagectomies performed annually: 7.7% and 3.8% for low and high-volume surgeons, respectively (P < 0.0001). Among surgeons with a low-volume esophagectomy experience, increasing volume of surrogate operations improved the outcomes observed for esophagectomy: 9.7%, 7.1%, and 4.3% for low, medium, and high-surrogate-volume surgeons, respectively (P = 0.016). Both operation-specific volume and surrogate volume are significant predictors of inhospital mortality for esophagectomy. Based on these observations, it would be premature to limit hospital privileges based solely on operation-specific surgeon volume criteria.

Evaluation of Fourier transform coefficients for the diagnosis of rheumatoid arthritis from diffuse optical tomography images

NASA Astrophysics Data System (ADS)

Montejo, Ludguier D.; Jia, Jingfei; Kim, Hyun K.; Hielscher, Andreas H.

2013-03-01

We apply the Fourier Transform to absorption and scattering coefficient images of proximal interphalangeal (PIP) joints and evaluate the performance of these coefficients as classifiers using receiver operator characteristic (ROC) curve analysis. We find 25 features that yield a Youden index over 0.7, 3 features that yield a Youden index over 0.8, and 1 feature that yields a Youden index over 0.9 (90.0% sensitivity and 100% specificity). In general, scattering coefficient images yield better one-dimensional classifiers compared to absorption coefficient images. Using features derived from scattering coefficient images we obtain an average Youden index of 0.58 +/- 0.16, and an average Youden index of 0.45 +/- 0.15 when using features from absorption coefficient images.

High reliability solid refractive index matching materials for field installable connections in FTTH network

NASA Astrophysics Data System (ADS)

Saito, Kotaro; Kihara, Mitsuru; Shimizu, Tomoya; Yoneda, Keisuke; Kurashima, Toshio

2015-06-01

We performed environmental and accelerated aging tests to ensure the long-term reliability of solid type refractive index matching material at a splice point. Stable optical characteristics were confirmed in environmental tests based on an IEC standard. In an accelerated aging test at 140 °C, which is very much higher than the specification test temperature, the index matching material itself and spliced fibers passing through it had steady optical characteristics. Then we performed an accelerated aging test on an index matching material attached to a built-in fiber before splicing it in the worst condition, which is different from the normal use configuration. As a result, we confirmed that the repeated insertion and removal of fiber for splicing resulted in failure. We consider that the repetition of adhesion between index matching material and fibers causes the splice to degrade. With this result, we used the Arrhenius model to estimate a median lifetime of about 68 years in a high temperature environment of 60 °C. Thus solid type index matching material at a splice point is highly reliable over long periods under normal conditions of use.

Body mass index and physical fitness in Brazilian adolescents.

PubMed

Lopes, Vitor P; Malina, Robert M; Gomez-Campos, Rossana; Cossio-Bolaños, Marco; Arruda, Miguel de; Hobold, Edilson

2018-05-05

Evaluate the relationship between body mass index and physical fitness in a cross-sectional sample of Brazilian youth. Participants were 3849 adolescents (2027 girls) aged 10-17 years. Weight and height were measured; body mass index was calculated. Physical fitness was evaluated with a multistage 20m shuttle run (cardiovascular endurance), standing long jump (power), and push-ups (upper body strength). Participants were grouped by sex into four age groups: 10-11, 12-13, 14-15, and 16-17 years. Sex-specific ANOVA was used to evaluate differences in each physical fitness item among weight status categories by age group. Relationships between body mass index and each physical fitness item were evaluated with quadratic regression models by age group within each sex. The physical fitness of thin and normal youth was, with few exceptions, significantly better than the physical fitness of overweight and obese youth in each age group by sex. On the other hand, physical fitness performances did not consistently differ, on average, between thin and normal weight and between overweight and obese youths. Results of the quadratic regressions indicated a curvilinear (parabolic) relationship between body mass index and each physical fitness item in most age groups. Better performances were attained by adolescents in the mid-range of the body mass index distribution, while performances of youth at the low and high ends of the body mass index distribution were lower. Relationships between the body mass index and physical fitness were generally nonlinear (parabolic) in youth 10-17 years. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Comparison of special judo fitness test and dynamic and isometric judo chin-up tests’ performance and classificatory tables’ development for cadet and junior athletes

PubMed Central

Agostinho, Marcus Fábio; Junior, José Alfredo Olivio; Stankovic, Nemanja; Escobar-Molina, Raquel; Franchini, Emerson

2018-01-01

The aims of this work were to compare the performances of male and female cadet and junior judo athletes and to develop classificatory tables to these judo-specific tests for international-level from these ages. Data collected during training camps of male and female cadet and junior judo teams from three nations (Brazil, Serbia, and Spain) were analyzed, totalizing 252 individual results of special judo fitness test (SJFT), and 222 and 208 of dynamic and isometric judogi chin-up tests, respectively. Juniors performed better than cadets in the SJFT, with higher number of throws in A, B, C, and total (P<0.001 for all comparisons), lower final heart rate (P=0.021), and lower index (P<0.001), as well as higher relative performance in the dynamic chin-up test (P<0.001). Furthermore, male athletes presented better performance compared to female athletes in the SJFT (higher number of throws in A, B and total, and lower index) and in the isometric and dynamic chin-up tests (higher absolute and relative performances) (P<0.001 for all comparisons). Considering these differences, tables were established by sex and age groups, using percentile values. Thereby, each of the parameters of the SJFT (number of throws, heart rate after and 1 min after the test, and SJFT index), as well as absolute and relative results in chin-up judogi tests, were classified by sex and age. These classificatory tables can be useful for judo coaches to monitor specific physical performance during different phases of periodization process. PMID:29740559

Measuring Academic Performance for Healthcare Researchers with the H Index: Which Search Tool Should Be Used?

PubMed Central

Patel, Vanash M.; Ashrafian, Hutan; Almoudaris, Alex; Makanjuola, Jonathan; Bucciarelli-Ducci, Chiara; Darzi, Ara; Athanasiou, Thanos

2013-01-01

Objectives To compare H index scores for healthcare researchers returned by Google Scholar, Web of Science and Scopus databases, and to assess whether a researcher's age, country of institutional affiliation and physician status influences calculations. Subjects and Methods One hundred and ninety-five Nobel laureates in Physiology and Medicine from 1901 to 2009 were considered. Year of first and last publications, total publications and citation counts, and the H index for each laureate were calculated from each database. Cronbach's alpha statistics was used to measure the reliability of H index scores between the databases. Laureate characteristic influence on the H index was analysed using linear regression. Results There was no concordance between the databases when considering the number of publications and citations count per laureate. The H index was the most reliably calculated bibliometric across the three databases (Cronbach's alpha = 0.900). All databases returned significantly higher H index scores for younger laureates (p < 0.0001). Google Scholar and Web of Science returned significantly higher H index for physician laureates (p = 0.025 and p = 0.029, respectively). Country of institutional affiliation did not influence the H index in any database. Conclusion The H index appeared to be the most consistently calculated bibliometric between the databases for Nobel laureates in Physiology and Medicine. Researcher-specific characteristics constituted an important component of objective research assessment. The findings of this study call to question the choice of current and future academic performance databases. PMID:22964880

Measurement of the relationship between perceived and computed color differences

NASA Astrophysics Data System (ADS)

García, Pedro A.; Huertas, Rafael; Melgosa, Manuel; Cui, Guihua

2007-07-01

Using simulated data sets, we have analyzed some mathematical properties of different statistical measurements that have been employed in previous literature to test the performance of different color-difference formulas. Specifically, the properties of the combined index PF/3 (performance factor obtained as average of three terms), widely employed in current literature, have been considered. A new index named standardized residual sum of squares (STRESS), employed in multidimensional scaling techniques, is recommended. The main difference between PF/3 and STRESS is that the latter is simpler and allows inferences on the statistical significance of two color-difference formulas with respect to a given set of visual data.

Ga-67 uptake in the lung in sarcoidosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, D.G.; Johnson, S.M.; Harris, C.C.

1984-02-01

Images were obtained with Ga-67 and bronchopulmonary lavage performed in 21 patients with sarcoidosis (31 studies). The Ga-67 index, a semiquantitative criterion, was compared to a quantitative computer index based on lung:liver activity ratios; accuracy in predicting active alveolitis (defined by lavage lymphocyte counts) was assessed and differences between 24- and 48-hour studies examined. Computer activity ratios correlated well with the Ga-67 index, which had a sensitivity of 64%, specificity of 71%, 82%, and 77%, respectively, for the computer scores. Scores at 24 and 48 hours were similar. These results suggest that (a) Ga-67 scanning is useful in staging activitymore » in pulmonary sarcoidosis, (b) quantitative computer scores are accurate in predicting disease activity, and (c) scanning can be performed 24 or 48 hours after injection.« less

The Marriage of Residential Energy Codes and Rating Systems: Conflict Resolution or Just Conflict?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, Zachary T.; Mendon, Vrushali V.

2014-08-21

After three decades of coexistence at a distance, model residential energy codes and residential energy rating systems have come together in the 2015 International Energy Conservation Code. At the October, 2013, International Code Council’s Public Comment Hearing, a new compliance path based on an Energy Rating Index was added to the IECC. Although not specifically named in the code, RESNET’s HERS rating system is the likely candidate Index for most jurisdictions. While HERS has been a mainstay in various beyond-code programs for many years, its direct incorporation into the most popular model energy code raises questions about the equivalence ofmore » a HERS-based compliance path and the traditional IECC performance compliance path, especially because the two approaches use different efficiency metrics, are governed by different simulation rules, and have different scopes with regard to energy impacting house features. A detailed simulation analysis of more than 15,000 house configurations reveals a very large range of HERS Index values that achieve equivalence with the IECC’s performance path. This paper summarizes the results of that analysis and evaluates those results against the specific Energy Rating Index values required by the 2015 IECC. Based on the home characteristics most likely to result in disparities between HERS-based compliance and performance path compliance, potential impacts on the compliance process, state and local adoption of the new code, energy efficiency in the next generation of homes subject to this new code, and future evolution of model code formats are discussed.« less

Characterization of Chronic Aortic and Mitral Regurgitation Undergoing Valve Surgery Using Cardiovascular Magnetic Resonance.

PubMed

Polte, Christian L; Gao, Sinsia A; Johnsson, Åse A; Lagerstrand, Kerstin M; Bech-Hanssen, Odd

2017-06-15

Grading of chronic aortic regurgitation (AR) and mitral regurgitation (MR) by cardiovascular magnetic resonance (CMR) is currently based on thresholds, which are neither modality nor quantification method specific. Accordingly, this study sought to identify CMR-specific and quantification method-specific thresholds for regurgitant volumes (RVols), RVol indexes, and regurgitant fractions (RFs), which denote severe chronic AR or MR with an indication for surgery. The study comprised patients with moderate and severe chronic AR (n = 38) and MR (n = 40). Echocardiography and CMR was performed at baseline and in all operated AR/MR patients (n = 23/25) 10 ± 1 months after surgery. CMR quantification of AR: direct (aortic flow) and indirect method (left ventricular stroke volume [LVSV] - pulmonary stroke volume [PuSV]); MR: 2 indirect methods (LVSV - aortic forward flow [AoFF]; mitral inflow [MiIF] - AoFF). All operated patients had severe regurgitation and benefited from surgery, indicated by a significant postsurgical reduction in end-diastolic volume index and improvement or relief of symptoms. The discriminatory ability between moderate and severe AR was strong for RVol >40 ml, RVol index >20 ml/m 2 , and RF >30% (direct method) and RVol >62 ml, RVol index >31 ml/m 2 , and RF >36% (LVSV-PuSV) with a negative likelihood ratio ≤ 0.2. In MR, the discriminatory ability was very strong for RVol >64 ml, RVol index >32 ml/m 2 , and RF >41% (LVSV-AoFF) and RVol >40 ml, RVol index >20 ml/m 2 , and RF >30% (MiIF-AoFF) with a negative likelihood ratio < 0.1. In conclusion, CMR grading of chronic AR and MR should be based on modality-specific and quantification method-specific thresholds, as they differ largely from recognized guideline criteria, to assure appropriate clinical decision-making and timing of surgery. Copyright © 2017 Elsevier Inc. All rights reserved.

The Development of Statistical Models for Predicting Surgical Site Infections in Japan: Toward a Statistical Model-Based Standardized Infection Ratio.

PubMed

Fukuda, Haruhisa; Kuroki, Manabu

2016-03-01

To develop and internally validate a surgical site infection (SSI) prediction model for Japan. Retrospective observational cohort study. We analyzed surveillance data submitted to the Japan Nosocomial Infections Surveillance system for patients who had undergone target surgical procedures from January 1, 2010, through December 31, 2012. Logistic regression analyses were used to develop statistical models for predicting SSIs. An SSI prediction model was constructed for each of the procedure categories by statistically selecting the appropriate risk factors from among the collected surveillance data and determining their optimal categorization. Standard bootstrapping techniques were applied to assess potential overfitting. The C-index was used to compare the predictive performances of the new statistical models with those of models based on conventional risk index variables. The study sample comprised 349,987 cases from 428 participant hospitals throughout Japan, and the overall SSI incidence was 7.0%. The C-indices of the new statistical models were significantly higher than those of the conventional risk index models in 21 (67.7%) of the 31 procedure categories (P<.05). No significant overfitting was detected. Japan-specific SSI prediction models were shown to generally have higher accuracy than conventional risk index models. These new models may have applications in assessing hospital performance and identifying high-risk patients in specific procedure categories.

Medical Subject Headings (MeSH) for indexing and retrieving open-source healthcare data.

PubMed

Marc, David T; Khairat, Saif S

2014-01-01

The US federal government initiated the Open Government Directive where federal agencies are required to publish high value datasets so that they are available to the public. Data.gov and the community site Healthdata.gov were initiated to disperse such datasets. However, data searches and retrieval for these sites are keyword driven and severely limited in performance. The purpose of this paper is to address the issue of extracting relevant open-source data by proposing a method of adopting the MeSH framework for indexing and data retrieval. A pilot study was conducted to compare the performance of traditional keywords to MeSH terms for retrieving relevant open-source datasets related to "mortality". The MeSH framework resulted in greater sensitivity with comparable specificity to the keyword search. MeSH showed promise as a method for indexing and retrieving data, yet future research should conduct a larger scale evaluation of the performance of the MeSH framework for retrieving relevant open-source healthcare datasets.

A hospital-specific template for benchmarking its cost and quality.

PubMed

Silber, Jeffrey H; Rosenbaum, Paul R; Ross, Richard N; Ludwig, Justin M; Wang, Wei; Niknam, Bijan A; Saynisch, Philip A; Even-Shoshan, Orit; Kelz, Rachel R; Fleisher, Lee A

2014-10-01

Develop an improved method for auditing hospital cost and quality tailored to a specific hospital's patient population. Medicare claims in general, gynecologic and urologic surgery, and orthopedics from Illinois, New York, and Texas between 2004 and 2006. A template of 300 representative patients from a single index hospital was constructed and used to match 300 patients at 43 hospitals that had a minimum of 500 patients over a 3-year study period. From each of 43 hospitals we chose 300 patients most resembling the template using multivariate matching. We found close matches on procedures and patient characteristics, far more balanced than would be expected in a randomized trial. There were little to no differences between the index hospital's template and the 43 hospitals on most patient characteristics yet large and significant differences in mortality, failure-to-rescue, and cost. Matching can produce fair, directly standardized audits. From the perspective of the index hospital, "hospital-specific" template matching provides the fairness of direct standardization with the specific institutional relevance of indirect standardization. Using this approach, hospitals will be better able to examine their performance, and better determine why they are achieving the results they observe. © Health Research and Educational Trust.

Assessment of circumferential angle-closure by the iris-trabecular contact index with swept-source optical coherence tomography.

PubMed

Baskaran, Mani; Ho, Sue-Wei; Tun, Tin A; How, Alicia C; Perera, Shamira A; Friedman, David S; Aung, Tin

2013-11-01

To evaluate the diagnostic performance of the iris-trabecular contact (ITC) index, a measure of the degree of angle-closure, using swept-source optical coherence tomography (SSOCT, CASIA SS-1000, Tomey Corporation, Nagoya, Japan) in comparison with gonioscopy. Prospective observational study. A total of 108 normal subjects and 32 subjects with angle-closure. The SSOCT 3-dimensional angle scans, which obtain radial scans for the entire circumference of the angle, were performed under dark conditions and analyzed using customized software by a single examiner masked to the subjects' clinical details. The ITC index was calculated as a percentage of the angle that was closed on SSOCT images. First-order agreement coefficient (AC1) statistics and area under the receiver operating characteristic curve (AUC) analyses were performed for angle-closure on the basis of the ITC index in comparison with gonioscopy. Angle-closure on gonioscopy was defined as nonvisibility of posterior trabecular meshwork for at least 2 quadrants. Agreement of the ITC index with gonioscopically defined angle-closure was assessed using the AC1 statistic. Study subjects were predominantly Chinese (95.7%) and female (70.7%), with a mean age of 59.2 (standard deviation, 8.9) years. The median ITC index was 15.24% for gonioscopically open-angle eyes (n = 108) and 48.5% for closed-angle eyes (n = 32) (P = 0.0001). The agreement for angle-closure based on ITC index cutoffs (>35% and ≥50%) and gonioscopic angle-closure was 0.699 and 0.718, respectively. The AUC for angle-closure detection using the ITC index was 0.83 (95% confidence interval, 0.76-0.89), with an ITC index >35% having a sensitivity of 71.9% and specificity of 84.3%. The ITC index is a summary measure of the circumferential extent of angle-closure as imaged with SSOCT. The index had moderate agreement and good diagnostic performance for angle-closure with gonioscopy as the reference standard. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

A Randomized Controlled Trial of an Activity Specific Exercise Program for Individuals With Alzheimer Disease in Long-term Care Settings

PubMed Central

Roach, Kathryn E.; Tappen, Ruth M.; Kirk-Sanchez, Neva; Williams, Christine L.; Loewenstein, David

2011-01-01

Objective To determine whether an activity specific exercise program could improve ability to perform basic mobility activities in long-term care residents with Alzheimer disease (AD). Design Randomized, controlled, single-blinded clinical trial. Setting Residents of 7 long-term care facilities. Participants Eighty-two long-term care residents with mild to severe AD. Intervention An activity specific exercise program was compared to a walking program and to an attention control. Measurements Ability to perform bed mobility and transfers were assessed using the subscales of the Acute Care Index of Function; functional mobility was measured using the 6-Minute Walk test. Results Subjects receiving the activity specific exercise program improved in ability to perform transfers, whereas subjects in the other 2 groups declined. PMID:21937893

A simple bedside blood test (Fibrofast; FIB-5) is superior to FIB-4 index for the differentiation between non-significant and significant fibrosis in patients with chronic hepatitis C.

PubMed

Shiha, G; Seif, S; Eldesoky, A; Elbasiony, M; Soliman, R; Metwally, A; Zalata, K; Mikhail, N

2017-05-01

A simple non-invasive score (Fibrofast, FIB-5) was developed using five routine laboratory tests (ALT, AST, alkaline phosphatase, albumin and platelets count) for the detection of significant hepatic fibrosis in patients with chronic hepatitis C. The FIB-4 index is a non-invasive test for the assessment of liver fibrosis, and a score of ≤1.45 enables the correct identification of patients who have non-significant (F0-1) from significant fibrosis (F2-4), and could avoid liver biopsy. The aim of this study was to compare the performance characteristics of FIB-5 and FIB-4 to differentiate between non-significant and significant fibrosis. A cross-sectional study included 604 chronic HCV patients. All liver biopsies were scored using the METAVIR system. Both FIB-5 and FIB-4 scores were measured and the performance characteristics were calculated using the ROC curve. The performance characteristics of FIB-5 at ≥7.5 and FIB-4 at ≤1.45 for the differentiation between non-significant fibrosis and significant fibrosis were: specificity 94.4%, PPV 85.7%, and specificity 54.9%, PPV 55.7% respectively. FIB-5 score at the new cutoff is superior to FIB-4 index for the differentiation between non-significant and significant fibrosis.

Value of Egy-Score in diagnosis of significant, advanced hepatic fibrosis and cirrhosis compared to aspartate aminotransferase-to-platelet ratio index, FIB-4 and Forns' index in chronic hepatitis C virus.

PubMed

Alboraie, Mohamed; Khairy, Marwa; Elsharkawy, Marwa; Asem, Noha; Elsharkawy, Aisha; Esmat, Gamal

2015-05-01

Serum markers and developed scores are of rising importance in non-invasive diagnosis of hepatic fibrosis. Aspartate aminotransferase-to-platelet ratio index (APRI), FIB-4 and Forns' index are validated scores used for diagnosis of liver fibrosis. The Egy-Score is a newly developed score for detection of hepatic fibrosis with promising results. We aimed to assess the accuracy of the Egy-Score in the diagnosis of significant fibrosis, advanced fibrosis and cirrhosis compared to APRI, FIB-4 and Forns' in chronic hepatitis C virus (HCV) patients. A retrospective study including 100 chronic hepatitis C naïve Egyptian patients was performed. Patients were classified according to stages of fibrosis into three groups: significant fibrosis (≥ F2), advanced fibrosis (≥ F3) and cirrhosis (F4). Egy-Score, APRI, FIB-4 and Forns' index were calculated. Regression analysis and receiver-operator curves were plotted to assess the sensitivity, specificity and predictive values for the significant scores with the best cut-off for diagnosis. An Egy-Score of 3.28 or more was superior to APRI, FIB-4 and Forns' index for detecting advanced fibrosis with a sensitivity of 91% and specificity of 78%. An Egy-Score of 3.67 or more was superior to APRI, FIB-4 and Forns' index for detecting cirrhosis with a sensitivity of 82% and specificity of 87%. Forns' index was superior to Egy-Score, FIB-4 and APRI for detecting significant fibrosis. The Egy-Score is a promising, accurate, easily calculated, cost-effective score in the prediction of hepatic fibrosis in chronic HCV patients with superiority over APRI, FIB-4 and Forns' index in advanced hepatic fibrosis and cirrhosis. © 2014 The Japan Society of Hepatology.

Body mass index predicts selected physical fitness attributes but is not associated with performance on military relevant tasks in U.S. Army Soldiers.

PubMed

Pierce, Joseph R; DeGroot, David W; Grier, Tyson L; Hauret, Keith G; Nindl, Bradley C; East, Whitfield B; McGurk, Michael S; Jones, Bruce H

2017-11-01

Army body composition standards are based upon validated criteria; however, certain field-expedient methodologies (e.g., weight-for-height, body mass index [BMI]) may disqualify individuals from service who may otherwise excel on physical performance and military-relevant tasks. The purpose was to assess soldier physical performance and military-specific task/fitness performance stratified by BMI. Cross-sectional observational study. Male (n=275) and female (n=46) soldiers performed a wide-array of physical fitness tests and military-specific tasks, including the Army physical fitness test (APFT). Within-sex performance data were analyzed by BMI tertile stratification or by Army Body Composition Program (ABCP) weight-for-height (calculated BMI) screening standards using ANOVA/Tukey post-hoc or independent t-tests, respectively. BMI stratification (higher vs. lower BMI) was associated with significant improvements in muscular strength and power, but also with decrements in speed/agility in male and female soldiers. Within the military specific tasks, a higher BMI was associated with an increased APFT 2-Mile Run time; however, performance on a 1600-m Loaded March or a Warrior Task and Battle Drill obstacle course was not related to BMI in either sex. Male and Female soldiers who did not meet ABCP screening standards demonstrated a slower 2-Mile Run time; however, not meeting the ABCP BMI standard only affected a minimal number (∼6%) of soldiers' ability to pass the APFT. Military body composition standards require a careful balance between physical performance, health, and military readiness. Allowances should be considered where tradeoffs exist between body composition classifications and performance on physical tasks with high military relevance. Published by Elsevier Ltd.

Testing of optical components to assure performance in a high-average-power environment

NASA Astrophysics Data System (ADS)

Chow, Robert; Taylor, John R.; Eickelberg, William K.; Primdahl, Keith A.

1997-11-01

Evaluation and testing of the optical components used in the atomic vapor laser isotope separation plant is critical for qualification of suppliers, developments of new optical multilayer designs and manufacturing processes, and assurance of performance in the production cycle. The range of specifications requires development of specialized test equipment and methods which are not routine or readily available in industry. Specifications are given on material characteristics such as index homogeneity, subsurface damage left after polishing, microscopic surface defects and contamination, coating absorption, and high average power laser damage. The approach to testing these performance characteristics and assuring the quality throughout the production cycle is described.

Real-time shear wave elastography may predict autoimmune thyroid disease.

PubMed

Vlad, Mihaela; Golu, Ioana; Bota, Simona; Vlad, Adrian; Timar, Bogdan; Timar, Romulus; Sporea, Ioan

2015-05-01

To evaluate and compare the values of the elasticity index as measured by shear wave elastography in healthy subjects and in patients with autoimmune thyroid disease, in order to establish if this investigation can predict the occurrence of autoimmune thyroid disease. A total of 104 cases were included in the study group: 91 women (87.5%), out of which 52 (50%) with autoimmune thyroid disease diagnosed by specific tests and 52 (50%) healthy volunteers, matched for age and gender. For all the subjects, three measurements were performed on each thyroid lobe and a mean value was calculated. The data were expressed in kPa. The investigation was performed with an Aixplorer system (SuperSonic Imagine, France), using a linear high-resolution 15-4 MHz transducer. The mean value for the elasticity index was similar in the right and the left thyroid lobes, both in normal subjects and in patients with autoimmune thyroid disease: 19.6 ± 6.6 vs. 19.5 ± 6.8 kPa, p = 0.92, and 26.6 ± 10.0 vs. 25.8 ± 11.7 kPa, p = 0.71, respectively. This parameter was significantly higher in patients with autoimmune thyroid disease than in controls (p < 0.001). For a cut-off value of 22.3 kPa, which resulted in the highest sum of sensitivity and specificity, the elasticity index assessed by shear wave elastography had a sensitivity of 59.6% and a specificity of 76.9% (AUROC = 0.71; p < 0.001) for predicting the presence of autoimmune thyroid disease. Quantitative elasticity index measured by shear wave elastography was significantly higher in autoimmune thyroid disease than in normal thyroid parenchyma and may predict the presence of autoimmune thyroid disease.

A new analysis of heart rate variability in the assessment of fetal parasympathetic activity: An experimental study in a fetal sheep model.

PubMed

Garabedian, C; Champion, C; Servan-Schreiber, E; Butruille, L; Aubry, E; Sharma, D; Logier, R; Deruelle, P; Storme, L; Houfflin-Debarge, V; De Jonckheere, J

2017-01-01

Analysis of heart rate variability (HRV) is a recognized tool in the assessment of autonomic nervous system (ANS) activity. Indeed, both time and spectral analysis techniques enable us to obtain indexes that are related to the way the ANS regulates the heart rate. However, these techniques are limited in terms of the lack of thresholds of the numerical indexes, which is primarily due to high inter-subject variability. We proposed a new fetal HRV analysis method related to the parasympathetic activity of the ANS. The aim of this study was to evaluate the performance of our method compared to commonly used HRV analysis, with regard to i) the ability to detect changes in ANS activity and ii) inter-subject variability. This study was performed in seven sheep fetuses. In order to evaluate the sensitivity and specificity of our index in evaluating parasympathetic activity, we directly administered 2.5 mg intravenous atropine, to inhibit parasympathetic tone, and 5 mg propranolol to block sympathetic activity. Our index, as well as time analysis (root mean square of the successive differences; RMSSD) and spectral analysis (high frequency (HF) and low frequency (LF) spectral components obtained via fast Fourier transform), were measured before and after injection. Inter-subject variability was estimated by the coefficient of variance (%CV). In order to evaluate the ability of HRV parameters to detect fetal parasympathetic decrease, we also estimated the effect size for each HRV parameter before and after injections. As expected, our index, the HF spectral component, and the RMSSD were reduced after the atropine injection. Moreover, our index presented a higher effect size. The %CV was far lower for our index than for RMSSD, HF, and LF. Although LF decreased after propranolol administration, fetal stress index, RMSSD, and HF were not significantly different, confirming the fact that those indexes are specific to the parasympathetic nervous system. In conclusion, our method appeared to be effective in detecting parasympathetic inhibition. Moreover, inter-subject variability was much lower, and effect size higher, with our method compared to other HRV analysis methods.

A pragmatic approach for mortality prediction after surgery in infective endocarditis: optimizing and refining EuroSCORE.

PubMed

Fernández-Hidalgo, N; Ferreria-González, I; Marsal, J R; Ribera, A; Aznar, M L; de Alarcón, A; García-Cabrera, E; Gálvez-Acebal, J; Sánchez-Espín, G; Reguera-Iglesias, J M; De La Torre-Lima, J; Lomas, J M; Hidalgo-Tenorio, C; Vallejo, N; Miranda, B; Santos-Ortega, A; Castro, M A; Tornos, P; García-Dorado, D; Almirante, B

2018-03-03

To simplify and optimize the ability of EuroSCORE I and II to predict early mortality after surgery for infective endocarditis (IE). Multicentre retrospective study (n = 775). Simplified scores, eliminating irrelevant variables, and new specific scores, adding specific IE variables, were created. The performance of the original, recalibrated and specific EuroSCOREs was assessed by Brier score, C-statistic and calibration plot in bootstrap samples. The Net Reclassification Index was quantified. Recalibrated scores including age, previous cardiac surgery, critical preoperative state, New York Heart Association >I, and emergent surgery (EuroSCORE I and II); renal failure and pulmonary hypertension (EuroSCORE I); and urgent surgery (EuroSCORE II) performed better than the original EuroSCOREs (Brier original and recalibrated: EuroSCORE I: 0.1770 and 0.1667; EuroSCORE II: 0.2307 and 0.1680). Performance improved with the addition of fistula, staphylococci and mitral location (EuroSCORE I and II) (Brier specific: EuroSCORE I 0.1587, EuroSCORE II 0.1592). Discrimination improved in specific models (C-statistic original, recalibrated and specific: EuroSCORE I: 0.7340, 0.7471 and 0.7728; EuroSCORE II: 0.7442, 0.7423 and 0.7700). Calibration improved in both EuroSCORE I models (intercept 0.295, slope 0.829 (original); intercept -0.094, slope 0.888 (recalibrated); intercept -0.059, slope 0.925 (specific)) but only in specific EuroSCORE II model (intercept 2.554, slope 1.114 (original); intercept -0.260, slope 0.703 (recalibrated); intercept -0.053, slope 0.930 (specific)). Net Reclassification Index was 5.1% and 20.3% for the specific EuroSCORE I and II CONCLUSIONS: The use of simplified EuroSCORE I and EuroSCORE II models in IE with the addition of specific variables may lead to simpler and more accurate models. Copyright © 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

The development of comparative bias index

NASA Astrophysics Data System (ADS)

Aimran, Ahmad Nazim; Ahmad, Sabri; Afthanorhan, Asyraf; Awang, Zainudin

2017-08-01

Structural Equation Modeling (SEM) is a second generation statistical analysis techniques developed for analyzing the inter-relationships among multiple variables in a model simultaneously. There are two most common used methods in SEM namely Covariance-Based Structural Equation Modeling (CB-SEM) and Partial Least Square Path Modeling (PLS-PM). There have been continuous debates among researchers in the use of PLS-PM over CB-SEM. While there is few studies were conducted to test the performance of CB-SEM and PLS-PM bias in estimating simulation data. This study intends to patch this problem by a) developing the Comparative Bias Index and b) testing the performance of CB-SEM and PLS-PM using developed index. Based on balanced experimental design, two multivariate normal simulation data with of distinct specifications of size 50, 100, 200 and 500 are generated and analyzed using CB-SEM and PLS-PM.

Towards An Improvement of Hospital Services and Streamlining of Health Care Costs: The DRG Analysis in Italy.

PubMed

Bellavia, M; Tomasello, G; Damiani, P; Damiani, F; Geraci, A; Accardo, Fm; Gioviale, Mc; Lo Monte, Ai

2012-01-01

The term Diagnosis-related Group (DRG) refers to a classification system used to assess hospital services with the aim of a better management of health care costs and improving performance. The DRG system focuses on the utilization of resources, and is not concerned with the specific type of care provided to the patient. This system highlights any diseconomies and eventual critical aspects of the hospital system. This article, starting from the history of heath care financing in Italy and pointing out the difficulty to define the "quality" of health care services, describes the variables used to evaluate correctly hospital performance based on the DRG system. These include Average Length of Stay, Average Daily Patient Load, Comparative Performance Index, and Case Mix Index.

Field variability and vulnerability index to identify precision agriculture opportunity

USDA-ARS?s Scientific Manuscript database

Innovations in precision agriculture (PA) have created opportunities to achieve a greater understanding of within-field variability. However, PA adoption has been hindered due to uncertainty about field-specific performance and return on investment. Uncertainty could be better addressed by analyzing...

Reactive Agility Performance in Handball; Development and Evaluation of a Sport-Specific Measurement Protocol

PubMed Central

Spasic, Miodrag; Krolo, Ante; Zenic, Natasa; Delextrat, Anne; Sekulic, Damir

2015-01-01

There is no current study that examined sport-specific tests of reactive-agility and change-of-direction-speed (CODS) to replicate real-sport environment in handball (team-handball). This investigation evaluated the reliability and validity of two novel tests designed to assess reactive-agility and CODS of handball players. Participants were female (25.14 ± 3.71 years of age; 1.77 ± 0.09 m and 74.1 ± 6.1 kg) and male handball players (26.9 ± 4.1 years of age; 1.90 ± 0.09 m and 93.90±4.6 kg). Variables included body height, body mass, body mass index, broad jump, 5-m sprint, CODS and reactive-agility tests. Results showed satisfactory reliability for reactive-agility-test and CODS-test (ICC of 0.85-0.93, and CV of 2.4-4.8%). The reactive-agility and CODS shared less than 20% of the common variance. The calculated index of perceptual and reactive capacity (P&RC; ratio between reactive-agility- and CODS-performance) is found to be valid measure in defining true-game reactive-agility performance in handball in both genders. Therefore, the handball athletes’ P&RC should be used in the evaluation of real-game reactive-agility performance. Future studies should explore other sport-specific reactive-agility tests and factors associated to such performance in sports involving agile maneuvers. Key points Reactive agility and change-of-direction-speed should be observed as independent qualities, even when tested over the same course and similar movement template The reactive-agility-performance of the handball athletes involved in defensive duties is closer to their non-reactive-agility-score than in their peers who are not involved in defensive duties The handball specific “true-game” reactive-agility-performance should be evaluated as the ratio between reactive-agility and corresponding CODS performance. PMID:26336335

Reactive Agility Performance in Handball; Development and Evaluation of a Sport-Specific Measurement Protocol.

PubMed

Spasic, Miodrag; Krolo, Ante; Zenic, Natasa; Delextrat, Anne; Sekulic, Damir

2015-09-01

There is no current study that examined sport-specific tests of reactive-agility and change-of-direction-speed (CODS) to replicate real-sport environment in handball (team-handball). This investigation evaluated the reliability and validity of two novel tests designed to assess reactive-agility and CODS of handball players. Participants were female (25.14 ± 3.71 years of age; 1.77 ± 0.09 m and 74.1 ± 6.1 kg) and male handball players (26.9 ± 4.1 years of age; 1.90 ± 0.09 m and 93.90±4.6 kg). Variables included body height, body mass, body mass index, broad jump, 5-m sprint, CODS and reactive-agility tests. Results showed satisfactory reliability for reactive-agility-test and CODS-test (ICC of 0.85-0.93, and CV of 2.4-4.8%). The reactive-agility and CODS shared less than 20% of the common variance. The calculated index of perceptual and reactive capacity (P&RC; ratio between reactive-agility- and CODS-performance) is found to be valid measure in defining true-game reactive-agility performance in handball in both genders. Therefore, the handball athletes' P&RC should be used in the evaluation of real-game reactive-agility performance. Future studies should explore other sport-specific reactive-agility tests and factors associated to such performance in sports involving agile maneuvers. Key pointsReactive agility and change-of-direction-speed should be observed as independent qualities, even when tested over the same course and similar movement templateThe reactive-agility-performance of the handball athletes involved in defensive duties is closer to their non-reactive-agility-score than in their peers who are not involved in defensive dutiesThe handball specific "true-game" reactive-agility-performance should be evaluated as the ratio between reactive-agility and corresponding CODS performance.

The effects of creatine supplementation on thermoregulation and isokinetic muscular performance following acute (3-day) supplementation.

PubMed

Rosene, J M; Matthews, T D; Mcbride, K J; Galla, A; Haun, M; Mcdonald, K; Gagne, N; Lea, J; Kasen, J; Farias, C

2015-12-01

The purpose of this investigation was to determine the effects of 3 d of creatine supplementation on thermoregulation and isokinetic muscular performance. Fourteen males performed two exercise bouts following 3 d of creatine supplementation and placebo. Subjects exercised for 60 min at 60-65% of VO2max in the heat followed by isokinetic muscular performance at 60, 180, and 300°·s(-1). Dependent variables for pre- and postexercise included nude body weight, urine specific gravity, and serum creatinine levels. Total body water, extracellular water and intracellular water were measured pre-exercise. Core temperature was assessed every 5 min during exercise. Peak torque and Fatigue Index were used to assess isokinetic muscular performance. Core temperature increased during the run for both conditions. Total body water and extracellular water were significantly greater (P<0.05) following creatine supplementation. No significant difference (P>0.05) was found between conditions for intracellular water, nude body weight, urine specific gravity, and serum creatinine. Pre-exercise scores for urine specific gravity and serum creatinine were significantly less (P<0.05) versus post-exercise. No significant differences (P>0.05) were found in peak torque values or Fatigue Index between conditions for each velocity. A significant (P<0.05) overall velocity effect was found for both flexion and extension. As velocity increased, mean peak torque values decreased. Three d of creatine supplementation does not affect thermoregulation during submaximal exercise in the heat and is not enough to elicit an ergogenic effect for isokinetic muscle performance following endurance activity.

Are Random Trading Strategies More Successful than Technical Ones?

PubMed Central

Biondo, Alessio Emanuele; Pluchino, Alessandro; Rapisarda, Andrea; Helbing, Dirk

2013-01-01

In this paper we explore the specific role of randomness in financial markets, inspired by the beneficial role of noise in many physical systems and in previous applications to complex socio-economic systems. After a short introduction, we study the performance of some of the most used trading strategies in predicting the dynamics of financial markets for different international stock exchange indexes, with the goal of comparing them to the performance of a completely random strategy. In this respect, historical data for FTSE-UK, FTSE-MIB, DAX, and S & P500 indexes are taken into account for a period of about 15–20 years (since their creation until today). PMID:23874594

Sensitivity and specificity of the Percentage of Consonants Correct-Revised in the identification of speech sound disorder.

PubMed

Barrozo, Tatiane Faria; Pagan-Neves, Luciana de Oliveira; Pinheiro da Silva, Joyce; Wertzner, Haydée Fiszbein

2017-05-22

The purpose of the study was to determine the sensitivity and specificity, and to establish cutoff points for the severity index Percentage of Consonants Correct - Revised (PCC-R) in Brazilian Portuguese-speaking children with and without speech sound disorders. 72 children between 5:00 and 7:11 years old - 36 children without speech and language complaints and 36 children with speech sound disorders. The PCC-R was applied to the figure naming and word imitation tasks that are part of the ABFW Child Language Test. Results were statistically analyzed. The ROC curve was performed and sensitivity and specificity values ​​of the index were verified. The group of children without speech sound disorders presented greater PCC-R values in both tasks, regardless of the gender of the participants. The cutoff value observed for the picture naming task was 93.4%, with a sensitivity value of 0.89 and specificity of 0.94 (age independent). For the word imitation task, results were age-dependent: for age group ≤6:5 years old, the cutoff value was 91.0% (sensitivity of 0.77 and specificity of 0.94) and for age group >6:5 years-old, the cutoff value was 93.9% (sensitivity of 0.93 and specificity of 0.94). Given the high sensitivity and specificity of PCC-R, we can conclude that the index was effective in discriminating and identifying children with and without speech sound disorders.

Use of the RSA/RCOD Index to Identify Training Priority in Soccer Players.

PubMed

Wong, Del P; Hjelde, Geir H; Cheng, Ching-Feng; Ngo, Jake K

2015-10-01

The use of RSA/RCOD index indicates the repeated change-of-direction (RCOD) performance relative to the repeated-sprint ability (RSA) and provides a standardized approach to prioritize training needs for RSA and RCOD. To compare the RSA/RCOD index among different age groups, RSA and RCOD were measured from 20 under-16 players (U16), 20 under-19 players (U19), and 17 first-team professional players (PRO) from a football (soccer) club that has regular participation in the UEFA Champions League. Each player performed the RSA and RCOD tests, during which the fastest time (FT), average time (AT), total time (TT), and percentage decrement score (%Dec) were recorded. No significant differences were found in RSA/RCOD index-FT, AT, TT, and %Dec among the 3 groups (p > 0.05) and between U19 and PRO in all RSA and RCOD measures (p > 0.05). Most values of RSA/RCOD index were 0.51 among the U16, U19, and PRO groups. Moreover, we concluded that the RSA/RCOD index might not be further changed after 16 years of age unless specific training programs for RSA and RCOD are prescribed. Therefore, this study provides an empirical case, and coaches can establish the RSA/RCOD index value relevant to their training system and monitor players' training needs of RSA and RCOD in a longer term.

Evaluating the potential of vegetation indices for winter wheat LAI estimation under different fertilization and water conditions

NASA Astrophysics Data System (ADS)

Xie, Qiaoyun; Huang, Wenjiang; Dash, Jadunandan; Song, Xiaoyu; Huang, Linsheng; Zhao, Jinling; Wang, Renhong

2015-12-01

Leaf area index (LAI) is an important indicator for monitoring crop growth conditions and forecasting grain yield. Many algorithms have been developed for remote estimation of the leaf area index of vegetation, such as using spectral vegetation indices, inversion of radiative transfer models, and supervised learning techniques. Spectral vegetation indices, mathematical combination of reflectance bands, are widely used for LAI estimation due to their computational simplicity and their applications ranged from the leaf scale to the entire globe. However, in many cases, their applicability is limited to specific vegetation types or local conditions due to species specific nature of the relationship used to transfer the vegetation indices to LAI. The overall objective of this study is to investigate the most suitable vegetation index for estimating winter wheat LAI under eight different types of fertilizer and irrigation conditions. Regression models were used to estimate LAI using hyperspectral reflectance data from the Pushbroom Hyperspectral Imager (PHI) and in-situ measurements. Our results showed that, among six vegetation indices investigated, the modified soil-adjusted vegetation index (MSAVI) and the normalized difference vegetation index (NDVI) exhibited strong and significant relationships with LAI, and thus were sensitive across different nitrogen and water treatments. The modified triangular vegetation index (MTVI2) confirmed its potential on crop LAI estimation, although second to MSAVI and NDVI in our study. The enhanced vegetation index (EVI) showed moderate performance. However, the ratio vegetation index (RVI) and the modified simple ratio index (MSR) predicted the least accurate estimations of LAI, exposing the simple band ratio index's weakness under different treatment conditions. The results support the use of vegetation indices for a quick and effective LAI mapping procedure that is suitable for winter wheat under different management practices.

Assessing the activity of sarcoidosis: quantitative /sup 67/Ga-citrate imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fajman, W.A.; Greenwald, L.V.; Staton, G.

1984-04-01

Three different methods of quantitating /sup 67/Ga-citrate lung images - a visual index, a computer-assisted index, and the total-lung-to-background ratio - were compared in 71 studies of patients with biopsy-proven sarcoidosis. Fifty consecutive cases were analyzed independently by two different observers using all three methods. In these studies, each index was correlated with the cell differential in the bronchoalveolar lavage fluid. The total-lung-to-background ratio proved to be the simplest to perform; correlated best with the original visual index and the percentage of lymphocytes obtained in bronchoalveolar lavage fluid. Sensitivity for detecting active disease was 84% compared with 64% and 58%more » for the visual and computer-assisted indices, respectively, with no sacrifice in specificity.« less

An index with improved diagnostic accuracy for the diagnosis of Crohn's disease derived from the Lennard-Jones criteria.

PubMed

Reinisch, S; Schweiger, K; Pablik, E; Collet-Fenetrier, B; Peyrin-Biroulet, L; Alfaro, I; Panés, J; Moayyedi, P; Reinisch, W

2016-09-01

The Lennard-Jones criteria are considered the gold standard for diagnosing Crohn's disease (CD) and include the items granuloma, macroscopic discontinuity, transmural inflammation, fibrosis, lymphoid aggregates and discontinuous inflammation on histology. The criteria have never been subjected to a formal validation process. To develop a validated and improved diagnostic index based on the items of Lennard-Jones criteria. Included were 328 adult patients with long-standing CD (median disease duration 10 years) from three centres and classified as 'established', 'probable' or 'non-CD' by Lennard-Jones criteria at time of diagnosis. Controls were patients with ulcerative colitis (n = 170). The performance of each of the six diagnostic items of Lennard-Jones criteria was modelled by logistic regression and a new index based on stepwise backward selection and cut-offs was developed. The diagnostic value of the new index was analysed by comparing sensitivity, specificity and accuracy vs. Lennard-Jones criteria. By Lennard-Jones criteria 49% (n = 162) of CD patients would have been diagnosed as 'non-CD' at time of diagnosis (sensitivity/specificity/accuracy, 'established' CD: 0.34/0.99/0.67; 'probable' CD: 0.51/0.95/0.73). A new index was derived from granuloma, fibrosis, transmural inflammation and macroscopic discontinuity, but excluded lymphoid aggregates and discontinuous inflammation on histology. Our index provided improved diagnostic accuracy for 'established' and 'probable' CD (sensitivity/specificity/accuracy, 'established' CD: 0.45/1/0.72; 'probable' CD: 0.8/0.85/0.82), including the subgroup isolated colonic CD ('probable' CD, new index: 0.73/0.85/0.79; Lennard-Jones criteria: 0.43/0.95/0.69). We developed an index based on items of Lennard-Jones criteria providing improved diagnostic accuracy for the differential diagnosis between CD and UC. © 2016 John Wiley & Sons Ltd.

Occupational heat strain in a hot underground metal mine.

PubMed

Lutz, Eric A; Reed, Rustin J; Turner, Dylan; Littau, Sally R

2014-04-01

In a hot underground metal mine, this study evaluated the relationship between job task, physical body type, work shift, and heat strain. Thirty-one miners were evaluated during 98 shifts while performing deep shaft-sinking tasks. Continuous core body temperature, heart rate, pre- and postshift urine specific gravity (USG), and body mass index were measured. Cutting and welding tasks were associated with significantly (P < 0.05) increased core body temperature, maximum heart rate, and increased postshift urine specific gravity. Miners in the obese level II and III body mass index categories, as well as those working night shift, had lower core body temperatures (P < 0.05). This study confirms that job task, body type, and shift are risk factors for heat strain.

Benefits of deep encoding in Alzheimer disease. Analysis of performance on a memory task using the Item Specific Deficit Approach.

PubMed

Oltra-Cucarella, J; Pérez-Elvira, R; Duque, P

2014-06-01

the aim of this study is to test the encoding deficit hypothesis in Alzheimer disease (AD) using a recent method for correcting memory tests. To this end, a Spanish-language adaptation of the Free and Cued Selective Reminding Test was interpreted using the Item Specific Deficit Approach (ISDA), which provides three indices: Encoding Deficit Index, Consolidation Deficit Index, and Retrieval Deficit Index. We compared the performances of 15 patients with AD and 20 healthy control subjects and analysed results using either the task instructions or the ISDA approach. patients with AD displayed deficient encoding of more than half the information, but items that were encoded properly could be retrieved later with the help of the same semantic clues provided individually during encoding. Virtually all the information retained over the long-term was retrieved by using semantic clues. Encoding was shown to be the most impaired process, followed by retrieval and consolidation. Discriminant function analyses showed that ISDA indices are more sensitive and specific for detecting memory impairments in AD than are raw scores. These results indicate that patients with AD present impaired information encoding, but they benefit from semantic hints that help them recover previously learned information. This should be taken into account for intervention techniques focusing on memory impairments in AD. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

A General Method for Automatic Computation of Equilibrium Compositions and Theoretical Rocket Performance of Propellants

NASA Technical Reports Server (NTRS)

Gordon, Sanford; Zeleznik, Frank J.; Huff, Vearl N.

1959-01-01

A general computer program for chemical equilibrium and rocket performance calculations was written for the IBM 650 computer with 2000 words of drum storage, 60 words of high-speed core storage, indexing registers, and floating point attachments. The program is capable of carrying out combustion and isentropic expansion calculations on a chemical system that may include as many as 10 different chemical elements, 30 reaction products, and 25 pressure ratios. In addition to the equilibrium composition, temperature, and pressure, the program calculates specific impulse, specific impulse in vacuum, characteristic velocity, thrust coefficient, area ratio, molecular weight, Mach number, specific heat, isentropic exponent, enthalpy, entropy, and several thermodynamic first derivatives.

Further Validation of the Conner's Adult Attention Deficit/Hyperactivity Rating Scale Infrequency Index (CII) for Detection of Non-Credible Report of Attention Deficit/Hyperactivity Disorder Symptoms.

PubMed

Cook, Carolyn M; Bolinger, Elizabeth; Suhr, Julie

2016-06-01

Attention deficit/hyperactivity disorder (ADHD) can be easily presented in a non-credible manner, through non-credible report of ADHD symptoms and/or by non-credible performance on neuropsychological tests. While most studies have focused on detection of non-credible performance using performance validity tests, there are few studies examining the ability to detect non-credible report of ADHD symptoms. We provide further validation data for a recently developed measure of non-credible ADHD symptom report, the Conner's Adult ADHD Rating Scales (CAARS) Infrequency Index (CII). Using archival data from 86 adults referred for concerns about ADHD, we examined the accuracy of the CII in detecting extreme scores on the CAARS and invalid reporting on validity indices of the Minnesota Multiphasic Personality Inventory-2 Restructured Format (MMPI-2-RF). We also examined the accuracy of the CII in detecting non-credible performance on standalone and embedded performance validity tests. The CII was 52% sensitive to extreme scores on CAARS DSM symptom subscales (with 97% specificity) and 20%-36% sensitive to invalid responding on MMPI-2-RF validity scales (with near 90% specificity), providing further evidence for the interpretation of the CII as an indicator of non-credible ADHD symptom report. However, the CII detected only 18% of individuals who failed a standalone performance validity test (Word Memory Test), with 87.8% specificity, and was not accurate in detecting non-credible performance using embedded digit span cutoffs. Future studies should continue to examine how best to assess for non-credible symptom report in ADHD referrals. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Application of the SAROTA index in real-life scenario

NASA Astrophysics Data System (ADS)

Rojatkar, A.; Monebhurrun, V.

2014-10-01

A unique parameter referred to as the SAROTA index which accounts for both the specific absorption rate (SAR) and the over-the-air (OTA) performance of a mobile phone was previously proposed to characterize the real-life exposure. The applicability of the SAROTA index was confirmed using SAR and total radiated power (TRP) data obtained under laboratory conditions wherein the power control (PC) enforced on the mobile phone was implemented artificially. Herein the investigation is extended to measurements conducted for the speech mode of operation in real-life scenarios. Based on the actual PC implemented during the communication with the base station, the instantaneous and average real-life exposure experienced by the mobile phone user is analyzed and compared to the predicted SAROTA index. To capture the PC in real-time, a set of hardware modified phones with embedded network monitoring software are used. The instantaneous uplink transmit power level (TX_LEV) along with various downlink parameters such as the receive signal level (RX_LEV) and received signal quality (RX_QUAL) of the communication link are thus available for performing a comprehensive RF exposure analysis.

Plan delivery quality assurance for CyberKnife: Statistical process control analysis of 350 film-based patient-specific QAs.

PubMed

Bellec, J; Delaby, N; Jouyaux, F; Perdrieux, M; Bouvier, J; Sorel, S; Henry, O; Lafond, C

2017-07-01

Robotic radiosurgery requires plan delivery quality assurance (DQA) but there has never been a published comprehensive analysis of a patient-specific DQA process in a clinic. We proposed to evaluate 350 consecutive film-based patient-specific DQAs using statistical process control. We evaluated the performance of the process to propose achievable tolerance criteria for DQA validation and we sought to identify suboptimal DQA using control charts. DQAs were performed on a CyberKnife-M6 using Gafchromic-EBT3 films. The signal-to-dose conversion was performed using a multichannel-correction and a scanning protocol that combined measurement and calibration in a single scan. The DQA analysis comprised a gamma-index analysis at 3%/1.5mm and a separate evaluation of spatial and dosimetric accuracy of the plan delivery. Each parameter was plotted on a control chart and control limits were calculated. A capability index (Cpm) was calculated to evaluate the ability of the process to produce results within specifications. The analysis of capability showed that a gamma pass rate of 85% at 3%/1.5mm was highly achievable as acceptance criteria for DQA validation using a film-based protocol (Cpm>1.33). 3.4% of DQA were outside a control limit of 88% for gamma pass-rate. The analysis of the out-of-control DQA helped identify a dosimetric error in our institute for a specific treatment type. We have defined initial tolerance criteria for DQA validations. We have shown that the implementation of a film-based patient-specific DQA protocol with the use of control charts is an effective method to improve patient treatment safety on CyberKnife. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Evaluating health of paddy rice field ecosystem with remote sensing and GIS in Lower Yangtze River Plain, China

NASA Astrophysics Data System (ADS)

Li, Jingjing; Qin, Zhihao; Li, Wenjuan; Lin, Lu

2008-10-01

A paddy rice ecosystem is a farming system composed of paddy, animals, microbes and other environmental factors in specific time and space, with particular temporal and spatial dynamics. Since paddy rice is a main grain crop to feed above half of population in China, the performance of paddy rice ecosystem is highly concerned to yield level of paddy and food supply safety in China. Therefore, monitoring the performance of paddy rice ecosystem is very important to obtain the required information for evaluation of ecosystem health. In the study we intend to develop an approach to monitor the ecosystem performance spatially and dynamically in a regional scale using MODIS remote sensing data and GIS spatial mapping. On the basis of key factors governing the paddy rice ecosystem, we accordingly develop the following three indicators for the evaluation: Crop growing index (CGI), environmental Index (EI), and pests-diseases index (PDI). Then, we integrated the three indicators into a model with different weight coefficients to calculate Comprehensive ecosystem health index (CEHI) to evaluate the performance and functioning of paddy rice ecosystem in a regional scale. CGI indicates the health status of paddy rice calculated from the normalizing enhanced vegetation Index (EVI) retrieved from MODIS data. EI is estimated from temperature Index (TI) and precipitation Index (PI) indicating heat and water stress on the rice field. PDI reflects the damage brought by pests and diseases, which can be estimated using the information obtained from governmental websites. Applying the approach to Lower Yangtze River Plain, we monitor and evaluate the performance of paddy rice ecosystem in various stages of rice growing period in 2006. The results indicated that the performance of the ecosystem was generally very encouraging. During booting stage and heading and blooming stage, the health level was the highest in Anhui province, which is the main paddy rice producer in the region. During stage of yellow ripeness, Jiangsu province had the lowest level of performance. Yield level of paddy rice in 2006 confirms that the applicability of the proposed approach for a rapid evaluation and monitoring of agricultural ecosystem performance in Lower Yangtze River Plain. As a result, the new approach could supply scientific basis for relevant departments taking policies and measures to make sure stable development of paddy yield.

[The study of establishment of the " Chinese provincial Blindness prevention technical guidance group performance evaluation system"].

PubMed

Lu, L N; He, X G; Zhu, J F; Xu, X; Zhang, R; Hu, X; Zou, H D

2016-11-11

Objective: To establish an assessment system, including indexes and scoring methods, that can be used for performance evaluation of the provincial blindness prevention technical guidance group properly and effectively . Methods: The indexes and scoring methods were set based on the core content of The " National Plan of Prevention and Treatment of Blindness (2012-2015)" , the specific requirement and target of the World Health Organization (WHO) "For the General Eye Health: Global plan of Action (2014-2019)" , and the current situation of the China's provinces and autonomous regions. These indexes should be of effectiveness, feasibility, comparability, guidance and advancing. Formed by a literature review of candidate indicators, the framework of the system is built by qualitative assessment. With the Delphi method, the system was further revised and improved. Empirical pilot study was then used to prove the feasibility, followed by the final qualitative analysis that establish the " Chinese provincial Blindness prevention technical guidance group performance evaluation system" . Results: Through the literature review and qualitative assessment, a six dimensional system framework was built, including 6 first-level indicators, 16 second-level indicators, and 29 third-level indicators through Delphi method evaluation. With the variation coefficient method, the coeffiences of the first-level index weight were calculated as: Organization and management 0.15, Development and implementation of blindness prevention plans 0.15, Implementation of blindness prevention projects 0.14, Training 0.17, Health education 0.18, and Cooperation and exchanges 0.21. The specific scoring method for this system is confirmed as: data and files check, field interview, and record interview, sampling investigation. Empirical pilot study was conducted in the Jilin, Guizhou and Gansu provinces, and the self-assessment results from local experts were consistent with the scores from the systems. Conclusion: This system established is appropriate at current time, and it can effectively evaluate the performance of the Chinese provincial Blindness prevention technical guidance group. (Chin J Ophthalmol, 2016, 52:814-824) .

Automatic indexing and retrieval of encounter-specific evidence for point-of-care support.

PubMed

O'Sullivan, Dympna M; Wilk, Szymon A; Michalowski, Wojtek J; Farion, Ken J

2010-08-01

Evidence-based medicine relies on repositories of empirical research evidence that can be used to support clinical decision making for improved patient care. However, retrieving evidence from such repositories at local sites presents many challenges. This paper describes a methodological framework for automatically indexing and retrieving empirical research evidence in the form of the systematic reviews and associated studies from The Cochrane Library, where retrieved documents are specific to a patient-physician encounter and thus can be used to support evidence-based decision making at the point of care. Such an encounter is defined by three pertinent groups of concepts - diagnosis, treatment, and patient, and the framework relies on these three groups to steer indexing and retrieval of reviews and associated studies. An evaluation of the indexing and retrieval components of the proposed framework was performed using documents relevant for the pediatric asthma domain. Precision and recall values for automatic indexing of systematic reviews and associated studies were 0.93 and 0.87, and 0.81 and 0.56, respectively. Moreover, precision and recall for the retrieval of relevant systematic reviews and associated studies were 0.89 and 0.81, and 0.92 and 0.89, respectively. With minor modifications, the proposed methodological framework can be customized for other evidence repositories. Copyright 2010 Elsevier Inc. All rights reserved.

Differences in the intellectual profile of children with intellectual vs. learning disability.

PubMed

Cornoldi, Cesare; Giofrè, David; Orsini, Arturo; Pezzuti, Lina

2014-09-01

The WISC-IV was used to compare the intellectual profile of two groups of children, one with specific learning disorders (SLDs), the other with intellectual disabilities (ID), with a view to identifying which of the four main factor indexes and two additional indexes can distinguish between the groups. We collected information on WISC-IV scores for 267 children (Mage=10.61 [SD=2.51], range 6-16 years, females=99) with a diagnosis of either SLD or ID. Children with SLD performed better than those with ID in all measures. Only the SLD children, not the ID children, revealed significant differences in the four main factor indexes, and their scores for the additional General Ability Index (GAI) were higher than for the Cognitive Proficiency Index (CPI). Children with a diagnosis of SLD whose Full-Scale Intelligence Quotient (FSIQ) was <85 showed a similar pattern. Our findings confirm the hypothesis that children with SLD generally obtain high GAI scores, but have specific deficiencies relating to working memory and processing speed, whereas children with ID have a general intellectual impairment. These findings have important diagnostic and clinical implications and should be considered when making diagnostic decisions in borderline cognitive cases. Copyright © 2014 Elsevier Ltd. All rights reserved.

Can transient elastography, Fib-4, Forns Index, and Lok Score predict esophageal varices in HCV-related cirrhotic patients?

PubMed

Hassan, Eman M; Omran, Dalia A; El Beshlawey, Mohamad L; Abdo, Mahmoud; El Askary, Ahmad

2014-02-01

Gastroesophageal varices are present in approximately 50% of patients with liver cirrhosis. The aim of this study was to evaluate liver stiffness measurement (LSM), Fib-4, Forns Index and Lok Score as noninvasive predictors of esophageal varices (EV). This prospective study included 65 patients with HCV-related liver cirrhosis. All patients underwent routine laboratory tests, transient elastograhy (TE) and esophagogastroduodenoscopy. FIB-4, Forns Index and Lok Score were calculated. The diagnostic performances of these methods were assessed using sensitivity, specificity, positive predictive value, negative predictive value, accuracy and receiver operating characteristic curves. All predictors (LSM, FIB-4, Forns Index and Lok Score) demonstrated statistically significant correlation with the presence and the grade of EV. TE could diagnose EV at a cutoff value of 18.2kPa. Fib-4, Forns Index, and Lok Score could diagnose EV at cutoff values of 2.8, 6.61 and 0.63, respectively. For prediction of large varices (grade 2, 3), LSM showed the highest accuracy (80%) with a cutoff of 22.4kPa and AUROC of 0.801. Its sensitivity was 84%, specificity 72%, PPV 84% and NPV 72%. The diagnostic accuracies of FIB-4, Forns Index and Lok Score were 70%, 70% and76%, respectively, at cutoffs of 3.3, 6.9 and 0.7, respectively. For diagnosis of large esophageal varices, adding TE to each of the other diagnostic indices (serum fibrosis scores) increased their sensitivities with little decrease in their specificities. Moreover, this combination decreased the LR- in all tests. Noninvasive predictors can restrict endoscopic screening. This is very important as non invasiveness is now a major goal in hepatology. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.

Nailfold videocapillaroscopy micro-haemorrhage and giant capillary counting as an accurate approach for a steady state definition of disease activity in systemic sclerosis.

PubMed

Sambataro, Domenico; Sambataro, Gianluca; Zaccara, Eleonora; Maglione, Wanda; Polosa, Riccardo; Afeltra, Antonella M V; Vitali, Claudio; Del Papa, Nicoletta

2014-10-09

Nailfold videocapillaroscopy (NVC) in systemic sclerosis (SSc) is a procedure commonly used for patient classification and subsetting, but not to define disease activity (DA). This study aimed to evaluate whether the number of micro-haemorrhages (MHE), micro-thrombosis (MT), giant capillaries (GC), and normal/dilated capillaries (Cs) in NVC could predict DA in SSc. Eight-finger NVC was performed in 107 patients with SSc, and the total number of MHE/MT, GC, and the mean number of Cs were counted and defined as number of micro-haemorrhages (NEMO), GC and Cs scores, respectively. The European Scleroderma Study Group (ESSG) index constituted the gold standard for DA assessment, and scores ≥ 3.5 and = 3 were considered indicative of high and moderate activity, respectively. NEMO and GC scores were positively correlated with ESSG index (R = 0.65, P < 0.0001, and R = 0.47, P <0.0001, respectively), whilst Cs score showed a negative correlation with that DA index (R = -0.30, P <0.001). The area under the curve (AUC) of receiver operating characteristic plots, obtained by NEMO score sensitivity and specificity values in classifying patients with ESSG index ≥ 3.5, was significantly higher than the corresponding AUC derived from either GC or Cs scores (P <0.03 and P <0.0006, respectively). A modified score, defined by the presence of a given number of MHE/MT and GC, had a good performance in classifying active patients (ESSG index ≥ 3, sensitivity 95.1%, specificity 84.8%, accuracy 88.7%). MHE/MT and GC appear to be good indicators of DA in SSc, and enhances the role of NVC as an easy technique to identify active patients.

Prognostic evaluation of febrile neutropenia in apparently stable adult cancer patients

PubMed Central

Carmona-Bayonas, A; Gómez, J; González-Billalabeitia, E; Canteras, M; Navarrete, A; Gonzálvez, M L; Vicente, V; Ayala de la Peña, F

2011-01-01

Background: Predictive models to identify low-risk febrile neutropenia (FN) have been developed with heterogeneous samples, which included stable and unstable patients, solid tumours, acute leukaemia and bone marrow transplantation. These models fail to recognise 5–15% of cases with unexpected complications, and literature specifically addressing apparently stable patients (ASPs) is scarce. Methods: We reviewed 861 episodes of FN in outpatients with solid tumours, including 692 (80%) episodes with apparent clinical stability. We aimed to investigate the prognosis of this latter group and explore the possibility of stratifying it according to the presenting features. A case–control study was performed and the MASCC index was evaluated. Results: The rates of complications and bacteraemia in ASPs were 7.3% and 6.2%, respectively. The MASCC index yielded a low sensitivity to detect complications (36%). Prognostic factors were identified: ECOG performance status ⩾2, chronic bronchitis, chronic heart failure, stomatitis NCI grade ⩾2, monocytes <200 mm−3 and stress hyperglycaemia. Conclusion: A very simple assessment is useful to classify the patients with FN according to the risk of complications. A few additional variables may predict the clinical course of the patients. We additionally show that the MASCC index applied to this specific group has a low sensitivity to predict complications. PMID:21811253

Benchmarking road safety performance: Identifying a meaningful reference (best-in-class).

PubMed

Chen, Faan; Wu, Jiaorong; Chen, Xiaohong; Wang, Jianjun; Wang, Di

2016-01-01

For road safety improvement, comparing and benchmarking performance are widely advocated as the emerging and preferred approaches. However, there is currently no universally agreed upon approach for the process of road safety benchmarking, and performing the practice successfully is by no means easy. This is especially true for the two core activities of which: (1) developing a set of road safety performance indicators (SPIs) and combining them into a composite index; and (2) identifying a meaningful reference (best-in-class), one which has already obtained outstanding road safety practices. To this end, a scientific technique that can combine the multi-dimensional safety performance indicators (SPIs) into an overall index, and subsequently can identify the 'best-in-class' is urgently required. In this paper, the Entropy-embedded RSR (Rank-sum ratio), an innovative, scientific and systematic methodology is investigated with the aim of conducting the above two core tasks in an integrative and concise procedure, more specifically in a 'one-stop' way. Using a combination of results from other methods (e.g. the SUNflower approach) and other measures (e.g. Human Development Index) as a relevant reference, a given set of European countries are robustly ranked and grouped into several classes based on the composite Road Safety Index. Within each class the 'best-in-class' is then identified. By benchmarking road safety performance, the results serve to promote best practice, encourage the adoption of successful road safety strategies and measures and, more importantly, inspire the kind of political leadership needed to create a road transport system that maximizes safety. Copyright © 2015 Elsevier Ltd. All rights reserved.

Specificity and Transfer in Learning How to Follow Navigation Instructions

NASA Technical Reports Server (NTRS)

Healy, Alice F.; Schneider, Vivian L.; Barshi, Immanuel

2012-01-01

We report a series of experiments that use a navigation task in which instructions for navigating in a space displayed as grids on a computer screen are given to subjects who then attempt to follow them by mouse clicking on the grids. The navigation task was broken down into component dimensions (e.g., presentation mode of the instructions, length of the instructions, characteristics of the display, size of the grids, response type). For each task dimension, one condition was used at training and the same or another condition was used at test. Each task dimension was examined in terms of two measures. One measure provided an index of transfer (i.e., better performance at test than at training when test and training involved different conditions), and the other provided an index of specificity (i.e., better performance at test when training and test conditions were the same than when training and test conditions were different). By and large, these two indices were complementary, so there was evidence of either transfer or specificity but not both. For one dimension transfer but no specificity was evident, and for another dimension specificity but no transfer was evident. For the remaining dimensions, however, there was asymmetrical transfer, with transfer evident for some conditions and specificity evident for others. The findings are interpreted within the procedural reinstatement framework. They have practical implications concerning how to optimize training and how much fidelity to the testing situation is necessary when training.

Optimization of the efficiency of search operations in the relational database of radio electronic systems

NASA Astrophysics Data System (ADS)

Wajszczyk, Bronisław; Biernacki, Konrad

2018-04-01

The increase of interoperability of radio electronic systems used in the Armed Forces requires the processing of very large amounts of data. Requirements for the integration of information from many systems and sensors, including radar recognition, electronic and optical recognition, force to look for more efficient methods to support information retrieval in even-larger database resources. This paper presents the results of research on methods of improving the efficiency of databases using various types of indexes. The data structure indexing technique is a solution used in RDBMS systems (relational database management system). However, the analysis of the performance of indices, the description of potential applications, and in particular the presentation of a specific scale of performance growth for individual indices are limited to few studies in this field. This paper contains analysis of methods affecting the work efficiency of a relational database management system. As a result of the research, a significant increase in the efficiency of operations on data was achieved through the strategy of indexing data structures. The presentation of the research topic discussed in this paper mainly consists of testing the operation of various indexes against the background of different queries and data structures. The conclusions from the conducted experiments allow to assess the effectiveness of the solutions proposed and applied in the research. The results of the research indicate the existence of a real increase in the performance of operations on data using indexation of data structures. In addition, the level of this growth is presented, broken down by index types.

Artificial neural network aided non-invasive grading evaluation of hepatic fibrosis by duplex ultrasonography

PubMed Central

2012-01-01

Background Artificial neural networks (ANNs) are widely studied for evaluating diseases. This paper discusses the intelligence mode of an ANN in grading the diagnosis of liver fibrosis by duplex ultrasonogaphy. Methods 239 patients who were confirmed as having liver fibrosis or cirrhosis by ultrasound guided liver biopsy were investigated in this study. We quantified ultrasonographic parameters as significant parameters using a data optimization procedure applied to an ANN. 179 patients were typed at random as the training group; 60 additional patients were consequently enrolled as the validating group. Performance of the ANN was evaluated according to accuracy, sensitivity, specificity, Youden’s index and receiver operating characteristic (ROC) analysis. Results 5 ultrasonographic parameters; i.e., the liver parenchyma, thickness of spleen, hepatic vein (HV) waveform, hepatic artery pulsatile index (HAPI) and HV damping index (HVDI), were enrolled as the input neurons in the ANN model. The sensitivity, specificity and accuracy of the ANN model for quantitative diagnosis of liver fibrosis were 95.0%, 85.0% and 88.3%, respectively. The Youden’s index (YI) was 0.80. Conclusions The established ANN model had good sensitivity and specificity in quantitative diagnosis of hepatic fibrosis or liver cirrhosis. Our study suggests that the ANN model based on duplex ultrasound may help non-invasive grading diagnosis of liver fibrosis in clinical practice. PMID:22716936

Influence of the measurement location on the resistance index in the umbilical arteries: a hemodynamic approach.

PubMed

Vieyres, P; Durand, A; Patat, F; Descamps, P; Gregoire, J M; Pourcelot, D; Pourcelot, L

1991-12-01

A computer model was used to study the primary factors generating the reduction in resistance index, (S-D)/S, values observed by ultrasonic Doppler measurements in the umbilical artery, from the fetal insertion to the placental insertion (S represents the amplitude of the systolic peak and D the amplitude of the diastolic peak). This hemodynamic approach shows that the placental resistance is the primary factor, the viscosity and the cord length playing secondary roles. Clinically, the position of the measurement along the cord is an important factor. To increase the sensitivity of the index, the Doppler measurement must be performed near the fetal insertion, whereas a measurement near the placental insertion will make the Doppler examination more specific.

Novel immunological and nutritional-based prognostic index for gastric cancer.

PubMed

Sun, Kai-Yu; Xu, Jian-Bo; Chen, Shu-Ling; Yuan, Yu-Jie; Wu, Hui; Peng, Jian-Jun; Chen, Chuang-Qi; Guo, Pi; Hao, Yuan-Tao; He, Yu-Long

2015-05-21

To assess the prognostic significance of immunological and nutritional-based indices, including the prognostic nutritional index (PNI), neutrophil-lymphocyte ratio (NLR), and platelet-lymphocyte ratio in gastric cancer. We retrospectively reviewed 632 gastric cancer patients who underwent gastrectomy between 1998 and 2008. Areas under the receiver operating characteristic curve were calculated to compare the predictive ability of the indices, together with estimating the sensitivity, specificity and agreement rate. Univariate and multivariate analyses were performed to identify risk factors for overall survival (OS). Propensity score analysis was performed to adjust variables to control for selection bias. Each index could predict OS in gastric cancer patients in univariate analysis, but only PNI had independent prognostic significance in multivariate analysis before and after adjustment with propensity scoring (hazard ratio, 1.668; 95% confidence interval: 1.368-2.035). In subgroup analysis, a low PNI predicted a significantly shorter OS in patients with stage II-III disease (P = 0.019, P < 0.001), T3-T4 tumors (P < 0.001), or lymph node metastasis (P < 0.001). Canton score, a combination of PNI, NLR, and platelet, was a better indicator for OS than PNI, with the largest area under the curve for 12-, 36-, 60-mo OS and overall OS (P = 0.022, P = 0.030, P < 0.001, and P = 0.024, respectively). The maximum sensitivity, specificity, and agreement rate of Canton score for predicting prognosis were 84.6%, 34.9%, and 70.1%, respectively. PNI is an independent prognostic factor for OS in gastric cancer. Canton score can be a novel preoperative prognostic index in gastric cancer.

[Neuropsychological performance in neurofibromatosis type 1].

PubMed

Hernández Del Castillo, Lilia; Martínez Bermejo, Antonio; Portellano Pérez, José Antonio; Tirado Requero, Pilar; Garriz Luis, Alexandra; Velázquez Fragua, Ramón

2017-08-01

Neurofibromatosis type 1 (NF1) is a genetic disorder with various clinical manifestations that affect the peripheral and central nervous system, as well as the skin, bones and endocrine and vascular system. There is still insufficient knowledge of neuropsychological effects of NF1 on children, and there is some controversy about the cognitive deficits that defines the cognitive profile of patients affected by this disorder. In this study an analysis is made of the neuropsychological performance of a group of patients affected by NF1, compared with a control group of healthy children. A comparison was made between the neuropsychological performance of a group of 23 boys and girls with a mean age of 8.7 years (+/-1.39) and diagnosed with NF1, and a control group consisting of 21 healthy children, with mean age of 8.9 years (+/- 1.41) and with similar socio-demographic characteristics. The Wechsler Intelligence Scale for Children (WISC) was applied to evaluate the subjects of both groups. The group of patients affected with NF1 showed a lower performance in every primary index of WISC IV: Verbal Comprehension Index, Fluid Reasoning Index, Working Memory Index, Processing Speed Index, and full Scale IQ. Only in two subscales were no statistically significant differences observed: similarities and coding. The results show subtle and generalised neuropsychological alterations in the sample of children affected with NF1, which affect most of cognitive domains that have been evaluated. Proper specific and early neuropsychological treatment should be provided in order to prevent the high risk for these children of presenting learning difficulties and school failure. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Using Receiver Operating Characteristic Curve to Define the Cutoff Points of Voice Handicap Index Applied to Young Adult Male Smokers.

PubMed

Tafiadis, Dionysios; Chronopoulos, Spyridon K; Kosma, Evangelia I; Voniati, Louiza; Raptis, Vasilis; Siafaka, Vasiliki; Ziavra, Nausica

2017-07-11

Voice performance is an inextricable key factor of everyday life. Obviously, the deterioration of voice quality can cause various problems to human communication and can therefore reduce the performance of social skills (relevant to voice). The deterioration could be originated from changes inside the system of the vocal tract and larynx. Various prognostic methods exist, and among them is the Voice Handicap Index (VHI). This tool includes self-reported questionnaires, used for determining the cutoff points of total score and of its three domains relevant to young male Greek smokers. The interpretation of the calculated cutoff points can serve as a strong indicator of imminent or future evaluation by a clinician. Consistent with previous calculation, the VHI can also act as a feedback for smokers' voice condition and as monitoring procedure toward smoking cessation. Specifically, the sample consisted of 130 male nondysphonic smokers (aged 18-33 years) who all participated in the VHI test procedure. The test results (through receiver operating characteristic analysis) concluded to a total cutoff point score of 19.50 (sensitivity: 0.838, 1-specificity: 0). Also, in terms of constructs, the Functional domain was equal to 7.50 (sensitivity: 0.676, 1-specificity: 0.032), the Physical domain was equal to 7.50 (sensitivity: 0.706, 1-specificity: 0.032), and the Emotional domain was equal to 6.50 (sensitivity: 0.809, 1-specificity: 0.048). Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Cognitive profiles in bilingual children born to immigrant parents and Italian monolingual native children with specific learning disorders.

PubMed

Riva, Anna; Nacinovich, Renata; Bertuletti, Nadia; Montrasi, Valentina; Marchetti, Sara; Neri, Francesca; Bomba, Monica

2017-01-01

The aim of this study is to compare the Wechsler Intelligence Scale for Children ® - fourth edition IV (WISC IV) intellectual profile of two groups of children with specific learning disorder, a group of bilingual children and a group of monolingual Italian children, in order to identify possible significant differences between them. A group of 48 bilingual children and a group of 48 Italian monolingual children were included in this study. A preliminary comparison showed the homogeneity of the two groups regarding learning disorder typology and sociodemographic characteristics (age at WISC IV assessment, sex and years of education in Italy) with the exception of socioeconomic status. Socioeconomic status was then used as a covariate in the analysis. Even if the two groups were comparable in specific learning disorder severity and, in particular, in the text comprehension performance, our findings showed that the WISC IV performances of the bilingual group were significantly worse than the Italian group in Full Scale Intelligence Quotient ( P =0.03), in General Ability Index ( P =0.03), in Working Memory Index ( P =0.009) and in some subtests and clusters requiring advanced linguistic abilities. These results support the hypothesis of a weakness in metalinguistic abilities in bilingual children with specific learning disorders than monolinguals. If confirmed, this result must be considered in the rehabilitation treatment.

Surgical Risk Preoperative Assessment System (SURPAS): II. Parsimonious Risk Models for Postoperative Adverse Outcomes Addressing Need for Laboratory Variables and Surgeon Specialty-specific Models.

PubMed

Meguid, Robert A; Bronsert, Michael R; Juarez-Colunga, Elizabeth; Hammermeister, Karl E; Henderson, William G

2016-07-01

To develop parsimonious prediction models for postoperative mortality, overall morbidity, and 6 complication clusters applicable to a broad range of surgical operations in adult patients. Quantitative risk assessment tools are not routinely used for preoperative patient assessment, shared decision making, informed consent, and preoperative patient optimization, likely due in part to the burden of data collection and the complexity of incorporation into routine surgical practice. Multivariable forward selection stepwise logistic regression analyses were used to develop predictive models for 30-day mortality, overall morbidity, and 6 postoperative complication clusters, using 40 preoperative variables from 2,275,240 surgical cases in the American College of Surgeons National Surgical Quality Improvement Program data set, 2005 to 2012. For the mortality and overall morbidity outcomes, prediction models were compared with and without preoperative laboratory variables, and generic models (based on all of the data from 9 surgical specialties) were compared with specialty-specific models. In each model, the cumulative c-index was used to examine the contribution of each added predictor variable. C-indexes, Hosmer-Lemeshow analyses, and Brier scores were used to compare discrimination and calibration between models. For the mortality and overall morbidity outcomes, the prediction models without the preoperative laboratory variables performed as well as the models with the laboratory variables, and the generic models performed as well as the specialty-specific models. The c-indexes were 0.938 for mortality, 0.810 for overall morbidity, and for the 6 complication clusters ranged from 0.757 for infectious to 0.897 for pulmonary complications. Across the 8 prediction models, the first 7 to 11 variables entered accounted for at least 99% of the c-index of the full model (using up to 28 nonlaboratory predictor variables). Our results suggest that it will be possible to develop parsimonious models to predict 8 important postoperative outcomes for a broad surgical population, without the need for surgeon specialty-specific models or inclusion of laboratory variables.

Municipal solid waste management: identification and analysis of engineering indexes representing demand and costs generated in virtuous Italian communities.

PubMed

Gamberini, R; Del Buono, D; Lolli, F; Rimini, B

2013-11-01

The definition and utilisation of engineering indexes in the field of Municipal Solid Waste Management (MSWM) is an issue of interest for technicians and scientists, which is widely discussed in literature. Specifically, the availability of consolidated engineering indexes is useful when new waste collection services are designed, along with when their performance is evaluated after a warm-up period. However, most published works in the field of MSWM complete their study with an analysis of isolated case studies. Conversely, decision makers require tools for information collection and exchange in order to trace the trends of these engineering indexes in large experiments. In this paper, common engineering indexes are presented and their values analysed in virtuous Italian communities, with the aim of contributing to the creation of a useful database whose data could be used during experiments, by indicating examples of MSWM demand profiles and the costs required to manage them. Copyright © 2013 Elsevier Ltd. All rights reserved.

Video quality assessment method motivated by human visual perception

NASA Astrophysics Data System (ADS)

He, Meiling; Jiang, Gangyi; Yu, Mei; Song, Yang; Peng, Zongju; Shao, Feng

2016-11-01

Research on video quality assessment (VQA) plays a crucial role in improving the efficiency of video coding and the performance of video processing. It is well acknowledged that the motion energy model generates motion energy responses in a middle temporal area by simulating the receptive field of neurons in V1 for the motion perception of the human visual system. Motivated by the biological evidence for the visual motion perception, a VQA method is proposed in this paper, which comprises the motion perception quality index and the spatial index. To be more specific, the motion energy model is applied to evaluate the temporal distortion severity of each frequency component generated from the difference of Gaussian filter bank, which produces the motion perception quality index, and the gradient similarity measure is used to evaluate the spatial distortion of the video sequence to get the spatial quality index. The experimental results of the LIVE, CSIQ, and IVP video databases demonstrate that the random forests regression technique trained by the generated quality indices is highly correspondent to human visual perception and has many significant improvements than comparable well-performing methods. The proposed method has higher consistency with subjective perception and higher generalization capability.

Solitary pulmonary nodules: Comparison of dynamic first-pass contrast-enhanced perfusion area-detector CT, dynamic first-pass contrast-enhanced MR imaging, and FDG PET/CT.

PubMed

Ohno, Yoshiharu; Nishio, Mizuho; Koyama, Hisanobu; Seki, Shinichiro; Tsubakimoto, Maho; Fujisawa, Yasuko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

2015-02-01

To prospectively compare the capabilities of dynamic perfusion area-detector computed tomography (CT), dynamic magnetic resonance (MR) imaging, and positron emission tomography (PET) combined with CT (PET/CT) with use of fluorine 18 fluorodeoxyglucose (FDG) for the diagnosis of solitary pulmonary nodules. The institutional review board approved this study, and written informed consent was obtained from each subject. A total of 198 consecutive patients with 218 nodules prospectively underwent dynamic perfusion area-detector CT, dynamic MR imaging, FDG PET/CT, and microbacterial and/or pathologic examinations. Nodules were classified into three groups: malignant nodules (n = 133) and benign nodules with low (n = 53) or high (n = 32) biologic activity. Total perfusion was determined with dual-input maximum slope models at area-detector CT, maximum and slope of enhancement ratio at MR imaging, and maximum standardized uptake value (SUVmax) at PET/CT. Next, all indexes for malignant and benign nodules were compared with the Tukey honest significant difference test. Then, receiver operating characteristic analysis was performed for each index. Finally, sensitivity, specificity, and accuracy were compared with the McNemar test. All indexes showed significant differences between malignant nodules and benign nodules with low biologic activity (P < .0001). The area under the receiver operating characteristic curve for total perfusion was significantly larger than that for other indexes (.0006 ≤ P ≤ .04). The specificity and accuracy of total perfusion were significantly higher than those of maximum relative enhancement ratio (specificity, P < .0001; accuracy, P < .0001), slope of enhancement ratio (specificity, P < .0001; accuracy, P < .0001), and SUVmax (specificity, P < .0001; accuracy, P < .0001). Dynamic perfusion area-detector CT is more specific and accurate than dynamic MR imaging and FDG PET/CT in the diagnosis of solitary pulmonary nodules in routine clinical practice. © RSNA, 2014.

A comparison of isomaltulose versus maltodextrin ingestion during soccer-specific exercise.

PubMed

Stevenson, Emma J; Watson, Anthony; Theis, Stephan; Holz, Anja; Harper, Liam D; Russell, Mark

2017-11-01

The performance and physiological effects of isomaltulose and maltodextrin consumed intermittently during prolonged soccer-specific exercise were investigated. University soccer players (n = 22) performed 120 min of intermittent exercise while consuming 8% carbohydrate-electrolyte drinks (equivalent to ~ 20 g h -1 ) containing maltodextrin (Glycaemic Index: 90-100), isomaltulose (Glycaemic Index: 32) or a carbohydrate-energy-free placebo in a manner replicating the practices of soccer players (i.e., during warm-up and half-time). Physical (sprinting, jumping) and technical (shooting, dribbling) performance was assessed. Blood glucose and plasma insulin (both P < 0.001) concentrations varied by trial with isomaltulose maintaining > 13% higher blood glucose concentrations between 75 and 90 min versus maltodextrin (P < 0.05). A decline in glycaemia at 60 min in maltodextrin was attenuated with isomaltulose (-19 versus -4%; P = 0.015). Carbohydrates attenuated elevations in plasma epinephrine concentrations (P < 0.05), but isomaltulose proved most effective at 90 and 120 min. Carbohydrates did not attenuate IL-6 increases or reductions in physical or technical performances (all P > 0.05). Ratings of abdominal discomfort were influenced by trial (P < 0.05) with lower values for both carbohydrates compared to PLA from 60 min onwards. Although carbohydrates (~ 20 g h -1 ) did not attenuate performance reductions throughout prolonged soccer-specific exercise, isomaltulose maintained higher blood glucose at 75-90 min, lessened the magnitude of the exercise-induced rebound glycaemic response and attenuated epinephrine increases whilst maintaining similar abdominal discomfort values relative to maltodextrin. When limited opportunities exist to consume carbohydrates on competition-day, low-glycaemic isomaltulose may offer an alternative nutritional strategy for exercising soccer players.

Development of multi-functional streetscape green infrastructure using a performance index approach.

PubMed

Tiwary, A; Williams, I D; Heidrich, O; Namdeo, A; Bandaru, V; Calfapietra, C

2016-01-01

This paper presents a performance evaluation framework for streetscape vegetation. A performance index (PI) is conceived using the following seven traits, specific to the street environments - Pollution Flux Potential (PFP), Carbon Sequestration Potential (CSP), Thermal Comfort Potential (TCP), Noise Attenuation Potential (NAP), Biomass Energy Potential (BEP), Environmental Stress Tolerance (EST) and Crown Projection Factor (CPF). Its application is demonstrated through a case study using fifteen street vegetation species from the UK, utilising a combination of direct field measurements and inventoried literature data. Our results indicate greater preference to small-to-medium size trees and evergreen shrubs over larger trees for streetscaping. The proposed PI approach can be potentially applied two-fold: one, for evaluation of the performance of the existing street vegetation, facilitating the prospects for further improving them through management strategies and better species selection; two, for planning new streetscapes and multi-functional biomass as part of extending the green urban infrastructure. Copyright © 2015 Elsevier Ltd. All rights reserved.

GeneRIF indexing: sentence selection based on machine learning.

PubMed

Jimeno-Yepes, Antonio J; Sticco, J Caitlin; Mork, James G; Aronson, Alan R

2013-05-31

A Gene Reference Into Function (GeneRIF) describes novel functionality of genes. GeneRIFs are available from the National Center for Biotechnology Information (NCBI) Gene database. GeneRIF indexing is performed manually, and the intention of our work is to provide methods to support creating the GeneRIF entries. The creation of GeneRIF entries involves the identification of the genes mentioned in MEDLINE®; citations and the sentences describing a novel function. We have compared several learning algorithms and several features extracted or derived from MEDLINE sentences to determine if a sentence should be selected for GeneRIF indexing. Features are derived from the sentences or using mechanisms to augment the information provided by them: assigning a discourse label using a previously trained model, for example. We show that machine learning approaches with specific feature combinations achieve results close to one of the annotators. We have evaluated different feature sets and learning algorithms. In particular, Naïve Bayes achieves better performance with a selection of features similar to one used in related work, which considers the location of the sentence, the discourse of the sentence and the functional terminology in it. The current performance is at a level similar to human annotation and it shows that machine learning can be used to automate the task of sentence selection for GeneRIF annotation. The current experiments are limited to the human species. We would like to see how the methodology can be extended to other species, specifically the normalization of gene mentions in other species.

On the necessity of new decision-making methods for cancer-associated, symptomatic, pulmonary embolism.

PubMed

Carmona-Bayonas, A; Font, C; Jiménez-Fonseca, P; Fenoy, Francisco; Otero, R; Beato, C; Plasencia, J; Biosca, M; Sánchez, M; Benegas, M; Calvo-Temprano, D; Varona, D; Faez, L; Vicente, M A; de la Haba, I; Antonio, M; Madridano, O; Ramchandani, A; Castañón, E; Marchena, P J; Martínez, M J; Martín, M; Marín, G; Ayala de la Peña, F; Vicente, V

2016-07-01

Acute symptomatic pulmonary embolism (PE) varies in its clinical manifestations in patients with cancer and entails specific issues. The objective is to assess the performance of five scores (PESI, sPESI, GPS, POMPE, and RIETE) and a clinical decision rule to predict 30-day mortality. This is an ambispective, observational, multicenter study that collected episodes of PE in patients with cancer from 13 Spanish centers. The main criterion for comparing scales was the c-indices and 95% confidence intervals (CIs) of the models for predicting 30-day mortality. 585 patients with acute symptomatic PE were recruited. The 30-day mortality rate was 21.3 (95% CI; 18.2-24.8%). The specific scales (POMPE-C and RIETE) were equally effective in discriminating prognosis (c-index of 0.775 and 0.757, respectively). None of these best performing scales was superior to the ECOG-PS with a c-index of 0.724. The remaining scores (PESI, sPESI, and GPS) performed worse, with c-indexes of 0.719, 0.705, and 0.722, respectively. The dichotomic "clinical decision rule" for ambulatory therapy was at least equally reliable in defining a low risk group: in the absence of all exclusion criteria, 30-day mortality was 2%, compared to 5% and 4% in the POMPE-C and RIETE low-risk categories, respectively. The accuracy of the five scales examined was not high enough to rely on to predict 30-day mortality and none of them contribute significantly to qualitative clinical judgment. Copyright © 2016 Elsevier Ltd. All rights reserved.

a Framework of Change Detection Based on Combined Morphologica Features and Multi-Index Classification

NASA Astrophysics Data System (ADS)

Li, S.; Zhang, S.; Yang, D.

2017-09-01

Remote sensing images are particularly well suited for analysis of land cover change. In this paper, we present a new framework for detection of changing land cover using satellite imagery. Morphological features and a multi-index are used to extract typical objects from the imagery, including vegetation, water, bare land, buildings, and roads. Our method, based on connected domains, is different from traditional methods; it uses image segmentation to extract morphological features, while the enhanced vegetation index (EVI), the differential water index (NDWI) are used to extract vegetation and water, and a fragmentation index is used to the correct extraction results of water. HSV transformation and threshold segmentation extract and remove the effects of shadows on extraction results. Change detection is performed on these results. One of the advantages of the proposed framework is that semantic information is extracted automatically using low-level morphological features and indexes. Another advantage is that the proposed method detects specific types of change without any training samples. A test on ZY-3 images demonstrates that our framework has a promising capability to detect change.

Modelling the meteorological forest fire niche in heterogeneous pyrologic conditions.

PubMed

De Angelis, Antonella; Ricotta, Carlo; Conedera, Marco; Pezzatti, Gianni Boris

2015-01-01

Fire regimes are strongly related to weather conditions that directly and indirectly influence fire ignition and propagation. Identifying the most important meteorological fire drivers is thus fundamental for daily fire risk forecasting. In this context, several fire weather indices have been developed focussing mainly on fire-related local weather conditions and fuel characteristics. The specificity of the conditions for which fire danger indices are developed makes its direct transfer and applicability problematic in different areas or with other fuel types. In this paper we used the low-to-intermediate fire-prone region of Canton Ticino as a case study to develop a new daily fire danger index by implementing a niche modelling approach (Maxent). In order to identify the most suitable weather conditions for fires, different combinations of input variables were tested (meteorological variables, existing fire danger indices or a combination of both). Our findings demonstrate that such combinations of input variables increase the predictive power of the resulting index and surprisingly even using meteorological variables only allows similar or better performances than using the complex Canadian Fire Weather Index (FWI). Furthermore, the niche modelling approach based on Maxent resulted in slightly improved model performance and in a reduced number of selected variables with respect to the classical logistic approach. Factors influencing final model robustness were the number of fire events considered and the specificity of the meteorological conditions leading to fire ignition.

Modelling the Meteorological Forest Fire Niche in Heterogeneous Pyrologic Conditions

PubMed Central

De Angelis, Antonella; Ricotta, Carlo; Conedera, Marco; Pezzatti, Gianni Boris

2015-01-01

Fire regimes are strongly related to weather conditions that directly and indirectly influence fire ignition and propagation. Identifying the most important meteorological fire drivers is thus fundamental for daily fire risk forecasting. In this context, several fire weather indices have been developed focussing mainly on fire-related local weather conditions and fuel characteristics. The specificity of the conditions for which fire danger indices are developed makes its direct transfer and applicability problematic in different areas or with other fuel types. In this paper we used the low-to-intermediate fire-prone region of Canton Ticino as a case study to develop a new daily fire danger index by implementing a niche modelling approach (Maxent). In order to identify the most suitable weather conditions for fires, different combinations of input variables were tested (meteorological variables, existing fire danger indices or a combination of both). Our findings demonstrate that such combinations of input variables increase the predictive power of the resulting index and surprisingly even using meteorological variables only allows similar or better performances than using the complex Canadian Fire Weather Index (FWI). Furthermore, the niche modelling approach based on Maxent resulted in slightly improved model performance and in a reduced number of selected variables with respect to the classical logistic approach. Factors influencing final model robustness were the number of fire events considered and the specificity of the meteorological conditions leading to fire ignition. PMID:25679957

Doppler-derived myocardial performance index in patients with impaired left ventricular relaxation and preserved systolic function.

PubMed

Fernandes, José Maria G; Rivera, Ivan Romero; de Oliveira Romão, Benício; Mendonça, Maria Alayde; Vasconcelos, Miriam Lira Castro; Carvalho, Antônio Carlos; Campos, Orlando; De Paola, Angelo Amato V; Moisés, Valdir A

2009-09-01

The Doppler-derived myocardial performance index (MPI) has been used in the evaluation of left ventricular (LV) function in several diseases. In patients with isolated diastolic dysfunction, the diagnostic utility of this index remains unclear. The aim of this study was to determine the diagnostic utility of MPI in patients with systemic hypertension, impaired LV relaxation, and normal ejection fraction. Thirty hypertensive patients with impaired LV relaxation were compared to 30 control subjects. MPI and its components, isovolumetric relaxation time (IRT), isovolumetric contraction time (ICT), and the ejection time (ET), were measured from LV outflow and mitral inflow Doppler velocity profiles. MPI was higher in patients than in control subjects (0.45 +/- 0.13 vs 0.37 +/- 0.07 P < 0.0029). The increase in MPI was due to the prolongation of IRT without significant change of ICT and ET. MPI cutoff value of > or =0.40 identified impaired LV relaxation with a sensitivity of 63% and specificity of 70% while an IRT >94 ms had a sensitivity of 67% and specificity of 80%. Multivariate analysis identified relative wall thickness, mitral early filling wave velocity (E), and systolic myocardial velocity (Sm) as independent predictors of MPI in patients with hypertension. MPI was increase in patients with hypertension, diastolic dysfunction, and normal ejection fraction but was not superior to IRT to detect impaired LV relaxation.

Assessing diabetic foot ulcer development risk with hyperspectral tissue oximetry

NASA Astrophysics Data System (ADS)

Yudovsky, Dmitry; Nouvong, Aksone; Schomacker, Kevin; Pilon, Laurent

2011-02-01

Foot ulceration remains a serious health concern for diabetic patients and has a major impact on the cost of diabetes treatment. Early detection and preventive care, such as offloading or improved hygiene, can greatly reduce the risk of further complications. We aim to assess the use of hyperspectral tissue oximetry in predicting the risk of diabetic foot ulcer formation. Tissue oximetry measurements are performed during several visits with hyperspectral imaging of the feet in type 1 and 2 diabetes mellitus subjects that are at risk for foot ulceration. The data are retrospectively analyzed at 21 sites that ulcerated during the course of our study and an ulceration prediction index is developed. Then, an image processing algorithm based on this index is implemented. This algorithm is able to predict tissue at risk of ulceration with a sensitivity and specificity of 95 and 80%, respectively, for images taken, on average, 58 days before tissue damage is apparent to the naked eye. Receiver operating characteristic analysis is also performed to give a range of sensitivity/specificity values resulting in a Q-value of 89%.

Evaluation of keratoconus progression.

PubMed

Shajari, Mehdi; Steinwender, Gernot; Herrmann, Kim; Kubiak, Kate Barbara; Pavlovic, Ivana; Plawetzki, Elena; Schmack, Ingo; Kohnen, Thomas

2018-06-01

To define variables for the evaluation of keratoconus progression and to determine cut-off values. In this retrospective cohort study (2010-2016), 265 eyes of 165 patients diagnosed with keratoconus underwent two Scheimpflug measurements (Pentacam) that took place 1 year apart ±3 months. Variables used for keratoconus detection were evaluated for progression and a correlation analysis was performed. By logistic regression analysis, a keratoconus progression index (KPI) was defined. Receiver-operating characteristic curve (ROC) analysis was performed and Youden Index calculated to determine cut-off values. Variables used for keratoconus detection showed a weak correlation with each other (eg, correlation r=0.245 between RPImin and Kmax, p<0.001). Therefore, we used parameters that took several variables into consideration (eg, D-index, index of surface variance, index for height asymmetry, KPI). KPI was defined by logistic regression and consisted of a Pachymin coefficient of -0.78 (p=0.001), a maximum elevation of back surface coefficient of 0.27 and coefficient of corneal curvature at the zone 3 mm away from the thinnest point on the posterior corneal surface of -12.44 (both p<0.001). The two variables with the highest Youden Index in the ROC analysis were D-index and KPI: D-index had a cut-off of 0.4175 (70.6% sensitivity) and Youden Index of 0.606. Cut-off for KPI was -0.78196 (84.7% sensitivity) and a Youden Index of 0.747; both 90% specificity. Keratoconus progression should be defined by evaluating parameters that consider several corneal changes; we suggest D-index and KPI to detect progression. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Aspergillus Galactomannan Enzyme Immunoassay and Quantitative PCR for Diagnosis of Invasive Aspergillosis with Bronchoalveolar Lavage Fluid

PubMed Central

Musher, Benjamin; Fredricks, David; Leisenring, Wendy; Balajee, S. Arunmozhi; Smith, Caitlin; Marr, Kieren A.

2004-01-01

Invasive pulmonary aspergillosis (IPA) is frequent and often fatal in hematopoietic stem cell transplant patients. Diagnosis requires microbiological or histopathologic demonstration of the organism in tissues; however, cultivation of Aspergillus species from respiratory secretions has low diagnostic sensitivity. Assays to detect Aspergillus antigen or DNA in bronchoalveolar lavage (BAL) fluid could facilitate earlier diagnosis, thereby guiding optimal therapy and obviating the need for additional costly and potentially morbid diagnostic evaluation. We evaluated the performance of a galactomannan enzyme immunoassay (GM EIA; Bio-Rad) by using a range of index cutoffs to define positivity and a quantitative PCR (qPCR) assay for the detection of Aspergillus species from BAL samples of patients with proven and probable IPA (case patients; n = 49) and without IPA (control patients; n = 50). The sensitivity of the GM EIA was 61% with an index cutoff of 1.0 and 76% with an index cutoff of 0.5; the corresponding specificities were 98 and 94%, respectively. The sensitivity and specificity of qPCR assay were 67 and 100%, respectively. The sensitivity with 22 culture-negative BAL specimens from patients with IPA was 41% for GM EIA with an index cutoff of 1.0, 59% for GM EIA with an index cutoff of 0.5, and 36% for qPCR assay. GM EIA indices and DNA quantities corresponded to BAL fungal burdens, with culture-positive samples having larger amounts of antigen and DNA compared to culture-negative samples. GM EIA and qPCR assay add to the sensitivity of BAL for diagnosing IPA in high-risk patients, with excellent specificity. Adjunctive use of these tests may reduce dependence on invasive diagnostic procedures. PMID:15583275

Load Index Metrics for an Optimized Management of Web Services: A Systematic Evaluation

PubMed Central

Souza, Paulo S. L.; Santana, Regina H. C.; Santana, Marcos J.; Zaluska, Ed; Faical, Bruno S.; Estrella, Julio C.

2013-01-01

The lack of precision to predict service performance through load indices may lead to wrong decisions regarding the use of web services, compromising service performance and raising platform cost unnecessarily. This paper presents experimental studies to qualify the behaviour of load indices in the web service context. The experiments consider three services that generate controlled and significant server demands, four levels of workload for each service and six distinct execution scenarios. The evaluation considers three relevant perspectives: the capability for representing recent workloads, the capability for predicting near-future performance and finally stability. Eight different load indices were analysed, including the JMX Average Time index (proposed in this paper) specifically designed to address the limitations of the other indices. A systematic approach is applied to evaluate the different load indices, considering a multiple linear regression model based on the stepwise-AIC method. The results show that the load indices studied represent the workload to some extent; however, in contrast to expectations, most of them do not exhibit a coherent correlation with service performance and this can result in stability problems. The JMX Average Time index is an exception, showing a stable behaviour which is tightly-coupled to the service runtime for all executions. Load indices are used to predict the service runtime and therefore their inappropriate use can lead to decisions that will impact negatively on both service performance and execution cost. PMID:23874776

Multi-objective engineering design using preferences

NASA Astrophysics Data System (ADS)

Sanchis, J.; Martinez, M.; Blasco, X.

2008-03-01

System design is a complex task when design parameters have to satisy a number of specifications and objectives which often conflict with those of others. This challenging problem is called multi-objective optimization (MOO). The most common approximation consists in optimizing a single cost index with a weighted sum of objectives. However, once weights are chosen the solution does not guarantee the best compromise among specifications, because there is an infinite number of solutions. A new approach can be stated, based on the designer's experience regarding the required specifications and the associated problems. This valuable information can be translated into preferences for design objectives, and will lead the search process to the best solution in terms of these preferences. This article presents a new method, which enumerates these a priori objective preferences. As a result, a single objective is built automatically and no weight selection need be performed. Problems occuring because of the multimodal nature of the generated single cost index are managed with genetic algorithms (GAs).

On the source of stochastic volatility: Evidence from CAC40 index options during the subprime crisis

NASA Astrophysics Data System (ADS)

Slim, Skander

2016-12-01

This paper investigates the performance of time-changed Lévy processes with distinct sources of return volatility variation for modeling cross-sectional option prices on the CAC40 index during the subprime crisis. Specifically, we propose a multi-factor stochastic volatility model: one factor captures the diffusion component dynamics and two factors capture positive and negative jump variations. In-sample and out-of-sample tests show that our full-fledged model significantly outperforms nested lower-dimensional specifications. We find that all three sources of return volatility variation, with different persistence, are needed to properly account for market pricing dynamics across moneyness, maturity and volatility level. Besides, the model estimation reveals negative risk premium for both diffusive volatility and downward jump intensity whereas a positive risk premium is found to be attributed to upward jump intensity.

Specificity of executive function and theory of mind performance in relation to attention-deficit/hyperactivity symptoms in autism spectrum disorders.

PubMed

Lukito, Steve; Jones, Catherine R G; Pickles, Andrew; Baird, Gillian; Happé, Francesca; Charman, Tony; Simonoff, Emily

2017-01-01

Individuals with autism spectrum disorder (ASD) frequently demonstrate symptoms of attention-deficit/hyperactivity disorder (ADHD). Previous findings in children with ASD have suggested that these symptoms are associated with an impairment in executive function (EF) abilities. However, studies rarely considered this association within a single framework that controls for other related factors such as Theory of Mind (ToM) abilities and ASD symptoms. We used structural equation modeling to explore the relations among EF, ToM, and symptoms of ASD and ADHD, using data from a population-based sample of 100 adolescents with ASD and full-scale IQ ≥ 50 (the Special Needs and Autism Project (SNAP) cohort). The study used a multi-measure and multi-informant approach, where performance of inhibition, planning, switching, and working memory tasks indexed EF and performance on tasks involving mentalizing indexed ToM. Measures of ASD and ADHD symptoms included parent and teacher reports and direct observation of the children. Shared source of symptom reporting was accounted for with a parental rating latent factor indexed by symptom measures reported by parents. Impairments in EF abilities were specifically associated with ADHD symptoms while impaired ToM was specifically associated with ASD symptoms, when accounting for the associations of each cognitive domain with the other factors. ASD and ADHD symptom latent factors were also correlated, but this association became nonsignificant once the shared source of reporting from parents was accounted for and within a model that also controlled for the correlated pathway between EF and ToM factors. The specific relations between the cognitive domains and behavioral symptoms remained even after controlling for IQ. In this ASD sample, symptoms of ADHD and ASD are underpinned by separate cognitive domains. The association between EF and ToM impairments is a likely partial explanation for the co-occurrence of ADHD symptoms in ASD, but the role of shared reporting effects is also important and supports the inclusion of independent informants and objective measures in future research.

Validation of simple indexes to assess insulin sensitivity during pregnancy in Wistar and Sprague-Dawley rats.

PubMed

Cacho, J; Sevillano, J; de Castro, J; Herrera, E; Ramos, M P

2008-11-01

Insulin resistance plays a role in the pathogenesis of diabetes, including gestational diabetes. The glucose clamp is considered the gold standard for determining in vivo insulin sensitivity, both in human and in animal models. However, the clamp is laborious, time consuming and, in animals, requires anesthesia and collection of multiple blood samples. In human studies, a number of simple indexes, derived from fasting glucose and insulin levels, have been obtained and validated against the glucose clamp. However, these indexes have not been validated in rats and their accuracy in predicting altered insulin sensitivity remains to be established. In the present study, we have evaluated whether indirect estimates based on fasting glucose and insulin levels are valid predictors of insulin sensitivity in nonpregnant and 20-day-pregnant Wistar and Sprague-Dawley rats. We have analyzed the homeostasis model assessment of insulin resistance (HOMA-IR), the quantitative insulin sensitivity check index (QUICKI), and the fasting glucose-to-insulin ratio (FGIR) by comparing them with the insulin sensitivity (SI(Clamp)) values obtained during the hyperinsulinemic-isoglycemic clamp. We have performed a calibration analysis to evaluate the ability of these indexes to accurately predict insulin sensitivity as determined by the reference glucose clamp. Finally, to assess the reliability of these indexes for the identification of animals with impaired insulin sensitivity, performance of the indexes was analyzed by receiver operating characteristic (ROC) curves in Wistar and Sprague-Dawley rats. We found that HOMA-IR, QUICKI, and FGIR correlated significantly with SI(Clamp), exhibited good sensitivity and specificity, accurately predicted SI(Clamp), and yielded lower insulin sensitivity in pregnant than in nonpregnant rats. Together, our data demonstrate that these indexes provide an easy and accurate measure of insulin sensitivity during pregnancy in the rat.

The skin aging index: a new approach for documenting anti-aging products or procedures.

PubMed

Nkengne, Alex; Roure, Romain; Rossi, Ana Beatriz; Bertin, Christiane

2013-08-01

The overall appearance of an aged skin is characterized by a combination of several attributes such as wrinkles, brown spots and sagging. Our objective was to develop and validate a statistical framework to assess the overall anti-ageing benefits of products/procedures. Different skin attributes were evaluated by a clinical grader and combined using a Principal Component Analysis (PCA). The Skin Ageing Index was defined as the normalized projection of the clinical grading values on the first PCA axis. Several Skin Indexes were built by grouping specific parameters related to a skin condition such as overall ageing, wrinkles and sagging. The method was validated following two steps. Firstly, a clinical study was performed on 173 Caucasian women and the correlation between the Skin Indexes and the volunteers' real and perceived age was estimated. Secondly, a double-blinded placebo-controlled randomized study was performed on 87 Caucasian women to assess the efficacy of an anti-wrinkle cream containing retinol, hyaluronic acid and dihydroxymethylchromone. Facial wrinkles were clinically evaluated and a Wrinkle Index was built. All indexes were highly correlated with the real and the perceived age (0.57 ≤ Pearson R ≤ 0.92, P-value ≤ 0.05). Finally, the Wrinkle Index provides documented evidence that the tested product significantly reduced the appearance of wrinkles versus the placebo and the baseline assessment (-23.53% after 4 weeks, -27.83% after 8 weeks). Skin ageing Indexes capture information relevant to the visual transformation of facial skin with age, while providing documented product benefits. These tools may enable a simpler and more consistent comparison of anti-ageing products/procedures. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Adiposity Indexes as Phenotype-Specific Markers of Preclinical Metabolic Alterations and Cardiovascular Risk in Polycystic Ovary Syndrome: A Cross-Sectional Study.

PubMed

Mario, Fernanda Missio; Graff, Scheila Karen; Spritzer, Poli Mara

2017-05-01

Polycystic ovary syndrome (PCOS) is a common condition in women of reproductive age. 2 PCOS phenotypes (classic and ovulatory) are currently recognized as the most prevalent, with important differences in terms of cardiometabolic features. We studied the performance of different adiposity indexes to predict preclinical metabolic alterations and cardiovascular risk in 234 women with PCOS (173 with classic and 61 with ovulatory PCOS) and 129 controls. Performance of waist circumference, waist-to-height ratio, conicity index, lipid accumulation product, and visceral adiposity index was assessed based on HOMA-IR ≥ 3.8 as reference standard for screening preclinical metabolic alterations and cardiovascular risk factors in each group. Lipid accumulation product had the best accuracy for classic PCOS, and visceral adiposity index had the best accuracy for ovulatory PCOS. By applying the cutoff point of lipid accumulation product<34, we identified a subgroup of patients without cardiometabolic alterations (P<0.05) in the group with classic PCOS, a population at higher risk for hypertension, dyslipidemia, and impaired glucose tolerance. In ovulatory PCOS, visceral adiposity index ≥ 1.32 was capable of detecting women with significantly higher blood pressure and less favorable glycemic and lipid variables as compared to ovulatory PCOS with lower visceral adiposity index (P<0.05). These results suggest LAP ≥ 34 as the best marker for classic PCOS, and VAI ≥ 1.32 for ovulatory PCOS women. Both indexes can be easily calculated with measures obtained in routine clinical practice and may be useful to detect cardiometabolic risk and secure early interventions. © Georg Thieme Verlag KG Stuttgart · New York.

Validation of the Pockit Dengue Virus Reagent Set for Rapid Detection of Dengue Virus in Human Serum on a Field-Deployable PCR System.

PubMed

Tsai, Jih-Jin; Liu, Li-Teh; Lin, Ping-Chang; Tsai, Ching-Yi; Chou, Pin-Hsing; Tsai, Yun-Long; Chang, Hsiao-Fen Grace; Lee, Pei-Yu Alison

2018-05-01

Dengue virus (DENV) infection, a mosquito-borne disease, is a major public health problem in tropical countries. Point-of-care DENV detection with good sensitivity and specificity enables timely early diagnosis of DENV infection, facilitating effective disease management and control, particularly in regions of low resources. The Pockit dengue virus reagent set (GeneReach Biotech), a reverse transcription insulated isothermal PCR (RT-iiPCR), is available to detect all four serotypes of DENV on the field-deployable Pockit system, which is ready for on-site applications. In this study, analytical and clinical performances of the assay were evaluated. The index assay did not react with 14 non-DENV human viruses, indicating good specificity. Compared to the U.S. CDC DENV-1-4 real-time quantitative RT-PCR (qRT-PCR) assay, testing with serial dilutions of virus-spiked human sera demonstrated that the index assay had detection endpoints that were separately comparable with the 4 serotypes. Excellent reproducibility was observed among repeat tests done by six operators at three sites. In clinical performance, 195 clinical sera collected around Kaohsiung city in 2012 and 21 DENV-4-spiked sera were tested with the RT-iiPCR and qRT-PCR assays in parallel. The 121 (11 DENV-1, 78 DENV-2, 11 DENV-3, and 21 DENV-4) qRT-PCR-positive and 95 qRT-PCR-negative samples were all positive and negative by the RT-iiPCR reagent results, respectively, demonstrating high (100%) interrater agreement (95% confidence interval [CI 95% ], ∼98.81% to 100%; κ = 1). With analytical and clinical performance equivalent to those of the reference qRT-PCR assay, the index PCR assay on the field-deployable system can serve as a highly sensitive and specific on-site tool for DENV detection. Copyright © 2018 American Society for Microbiology.

A Hospital-Specific Template for Benchmarking its Cost and Quality

PubMed Central

Silber, Jeffrey H; Rosenbaum, Paul R; Ross, Richard N; Ludwig, Justin M; Wang, Wei; Niknam, Bijan A; Saynisch, Philip A; Even-Shoshan, Orit; Kelz, Rachel R; Fleisher, Lee A

2014-01-01

Objective Develop an improved method for auditing hospital cost and quality tailored to a specific hospital’s patient population. Data Sources/Setting Medicare claims in general, gynecologic and urologic surgery, and orthopedics from Illinois, New York, and Texas between 2004 and 2006. Study Design A template of 300 representative patients from a single index hospital was constructed and used to match 300 patients at 43 hospitals that had a minimum of 500 patients over a 3-year study period. Data Collection/Extraction Methods From each of 43 hospitals we chose 300 patients most resembling the template using multivariate matching. Principal Findings We found close matches on procedures and patient characteristics, far more balanced than would be expected in a randomized trial. There were little to no differences between the index hospital’s template and the 43 hospitals on most patient characteristics yet large and significant differences in mortality, failure-to-rescue, and cost. Conclusion Matching can produce fair, directly standardized audits. From the perspective of the index hospital, “hospital-specific” template matching provides the fairness of direct standardization with the specific institutional relevance of indirect standardization. Using this approach, hospitals will be better able to examine their performance, and better determine why they are achieving the results they observe. PMID:25201167

Strategies to diagnose ovarian cancer: new evidence from phase 3 of the multicentre international IOTA study.

PubMed

Testa, A; Kaijser, J; Wynants, L; Fischerova, D; Van Holsbeke, C; Franchi, D; Savelli, L; Epstein, E; Czekierdowski, A; Guerriero, S; Fruscio, R; Leone, F P G; Vergote, I; Bourne, T; Valentin, L; Van Calster, B; Timmerman, D

2014-08-12

To compare different ultrasound-based international ovarian tumour analysis (IOTA) strategies and risk of malignancy index (RMI) for ovarian cancer diagnosis using a meta-analysis approach of centre-specific data from IOTA3. This prospective multicentre diagnostic accuracy study included 2403 patients with 1423 benign and 980 malignant adnexal masses from 2009 until 2012. All patients underwent standardised transvaginal ultrasonography. Test performance of RMI, subjective assessment (SA) of ultrasound findings, two IOTA risk models (LR1 and LR2), and strategies involving combinations of IOTA simple rules (SRs), simple descriptors (SDs) and LR2 with and without SA was estimated using a meta-analysis approach. Reference standard was histology after surgery. The areas under the receiver operator characteristic curves of LR1, LR2, SA and RMI were 0.930 (0.917-0.942), 0.918 (0.905-0.930), 0.914 (0.886-0.936) and 0.875 (0.853-0.894). Diagnostic one-step and two-step strategies using LR1, LR2, SR and SD achieved summary estimates for sensitivity 90-96%, specificity 74-79% and diagnostic odds ratio (DOR) 32.8-50.5. Adding SA when IOTA methods yielded equivocal results improved performance (DOR 57.6-75.7). Risk of Malignancy Index had sensitivity 67%, specificity 91% and DOR 17.5. This study shows all IOTA strategies had excellent diagnostic performance in comparison with RMI. The IOTA strategy chosen may be determined by clinical preference.

Fuzzy control for closed-loop, patient-specific hypnosis in intraoperative patients: a simulation study.

PubMed

Moore, Brett L; Pyeatt, Larry D; Doufas, Anthony G

2009-01-01

Research has demonstrated the efficacy of closed-loop control of anesthesia using bispectral index (BIS) as the controlled variable, and the recent development of model-based, patient-adaptive systems has considerably improved anesthetic control. To further explore the use of model-based control in anesthesia, we investigated the application of fuzzy control in the delivery of patient-specific propofol-induced hypnosis. In simulated intraoperative patients, the fuzzy controller demonstrated clinically acceptable performance, suggesting that further study is warranted.

Predicting the Performance of Chain Saw Machines Based on Shore Scleroscope Hardness

NASA Astrophysics Data System (ADS)

Tumac, Deniz

2014-03-01

Shore hardness has been used to estimate several physical and mechanical properties of rocks over the last few decades. However, the number of researches correlating Shore hardness with rock cutting performance is quite limited. Also, rather limited researches have been carried out on predicting the performance of chain saw machines. This study differs from the previous investigations in the way that Shore hardness values (SH1, SH2, and deformation coefficient) are used to determine the field performance of chain saw machines. The measured Shore hardness values are correlated with the physical and mechanical properties of natural stone samples, cutting parameters (normal force, cutting force, and specific energy) obtained from linear cutting tests in unrelieved cutting mode, and areal net cutting rate of chain saw machines. Two empirical models developed previously are improved for the prediction of the areal net cutting rate of chain saw machines. The first model is based on a revised chain saw penetration index, which uses SH1, machine weight, and useful arm cutting depth as predictors. The second model is based on the power consumed for only cutting the stone, arm thickness, and specific energy as a function of the deformation coefficient. While cutting force has a strong relationship with Shore hardness values, the normal force has a weak or moderate correlation. Uniaxial compressive strength, Cerchar abrasivity index, and density can also be predicted by Shore hardness values.

Comparative Approach of MRI-Based Brain Tumor Segmentation and Classification Using Genetic Algorithm.

PubMed

Bahadure, Nilesh Bhaskarrao; Ray, Arun Kumar; Thethi, Har Pal

2018-01-17

The detection of a brain tumor and its classification from modern imaging modalities is a primary concern, but a time-consuming and tedious work was performed by radiologists or clinical supervisors. The accuracy of detection and classification of tumor stages performed by radiologists is depended on their experience only, so the computer-aided technology is very important to aid with the diagnosis accuracy. In this study, to improve the performance of tumor detection, we investigated comparative approach of different segmentation techniques and selected the best one by comparing their segmentation score. Further, to improve the classification accuracy, the genetic algorithm is employed for the automatic classification of tumor stage. The decision of classification stage is supported by extracting relevant features and area calculation. The experimental results of proposed technique are evaluated and validated for performance and quality analysis on magnetic resonance brain images, based on segmentation score, accuracy, sensitivity, specificity, and dice similarity index coefficient. The experimental results achieved 92.03% accuracy, 91.42% specificity, 92.36% sensitivity, and an average segmentation score between 0.82 and 0.93 demonstrating the effectiveness of the proposed technique for identifying normal and abnormal tissues from brain MR images. The experimental results also obtained an average of 93.79% dice similarity index coefficient, which indicates better overlap between the automated extracted tumor regions with manually extracted tumor region by radiologists.

Quality of pharmacy-specific Medical Subject Headings (MeSH) assignment in pharmacy journals indexed in MEDLINE.

PubMed

Minguet, Fernando; Salgado, Teresa M; van den Boogerd, Lucienne; Fernandez-Llimos, Fernando

2015-01-01

The Medical Subject Headings (MeSH) is the National Library of Medicine (NLM) controlled vocabulary for indexing articles. Inaccuracies in the MeSH thesaurus have been reported for several areas including pharmacy. To assess the quality of pharmacy-specific MeSH assignment to articles indexed in pharmacy journals. The 10 journals containing the highest number of articles published in 2012 indexed under the MeSH 'Pharmacists' were identified. All articles published over a 5-year period (2008-2012) in the 10 previously selected journals were retrieved from PubMed. MeSH terms used to index these articles were extracted and pharmacy-specific MeSH terms were identified. The frequency of use of pharmacy-specific MeSH terms was calculated across journals. A total of 6989 articles were retrieved from the 10 pharmacy journals, of which 328 (4.7%) were articles not fully indexed and therefore did not contain any MeSH terms assigned. Among the 6661 articles fully indexed, the mean number of MeSH terms was 10.1 (SD = 4.0), being 1.0 (SD = 1.3) considered as Major MeSH. Both values significantly varied across journals. The mean number of pharmacy-specific MeSH terms per article was 0.9 (SD = 1.2). A total of 3490 (52.4%) of the 6661 articles were indexed in pharmacy journals without a single pharmacy-specific MeSH. Of the total 67193 MeSH terms assigned to articles, on average 10.5% (SD = 13.9) were pharmacy-specific MeSH. A statistically significant different pattern of pharmacy-specific MeSH assignment was identified across journals (Kruskal-Wallis P < 0.001). The quality of assignment of the existing pharmacy-specific MeSH terms to articles indexed in pharmacy journals can be improved to further enhance evidence gathering in pharmacy. Over half of the articles published in the top-10 journals publishing pharmacy literature were indexed without a single pharmacy-specific MeSH. Copyright © 2015 Elsevier Inc. All rights reserved.

Adiponectin/(FBG × FIns) as a predictor of insulin sensitivity and metabolic syndrome in patients with polycystic ovary syndrome.

PubMed

Xu, Xiaohui; Lai, Yerui; Yang, Gangyi; Yang, Mengliu; Li, Ling; Zhang, Qin; Liu, Hua; Zheng, Hongting; Zhu, Danping

2016-12-01

The euglycemic-hyperinsulinemic clamp is not available in most clinical settings. An accessible and inexpensive measurement for identifying insulin resistance (IR) is necessary. Our aim is to assess whether the adiponectin (ADI) index (ADI/[FBG × FIns]) is a better surrogate index for the assessment of IR or metabolic syndrome (MetS).A population-based cross-sectional study was conducted including 100 healthy women and 99 polycystic ovary syndrome patients. The euglycemic-hyperinsulinemic clamp was performed. Circulating ADI levels were determined by ELISA.Polycystic ovary syndrome and polycystic ovary syndrome plus MetS subjects had higher products of fasting triglycerides and glucose (TyG), Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), increased ratios of the area under the curve for insulin/the area under the curve for glucose (AUCi/AUCg), but lower ADI index as compared with healthy subjects. Partial correlation analysis in all populations showed that the M-value was significantly negatively correlated with HOMA-IR, TyG, TG/HDL, and AUCi/AUCg, and correlated positively with the ADI index. The r value of Pearson correlation between the ADI index and M-value was greater than that of the correlation between HOMA-IR, TyG, TG/HDL-C, and AUCi/AUCg. The optimal cut-off value of the ADI index for detection of IR was 0.67, with a sensitivity of 89.4% and a specificity of 88.1%, whereas for detection of MetS, it was 0.32, with a sensitivity of 88.7% and a specificity of 71.0%.The ADI index may be a surrogate marker in detecting IR and MetS.

Adiponectin/(FBG × FIns) as a predictor of insulin sensitivity and metabolic syndrome in patients with polycystic ovary syndrome

PubMed Central

Xu, Xiaohui; Lai, Yerui; Yang, Gangyi; Yang, Mengliu; Li, Ling; Zhang, Qin; Liu, Hua; Zheng, Hongting; Zhu, Danping

2016-01-01

Abstract The euglycemic–hyperinsulinemic clamp is not available in most clinical settings. An accessible and inexpensive measurement for identifying insulin resistance (IR) is necessary. Our aim is to assess whether the adiponectin (ADI) index (ADI/[FBG × FIns]) is a better surrogate index for the assessment of IR or metabolic syndrome (MetS). A population-based cross-sectional study was conducted including 100 healthy women and 99 polycystic ovary syndrome patients. The euglycemic–hyperinsulinemic clamp was performed. Circulating ADI levels were determined by ELISA. Polycystic ovary syndrome and polycystic ovary syndrome plus MetS subjects had higher products of fasting triglycerides and glucose (TyG), Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), increased ratios of the area under the curve for insulin/the area under the curve for glucose (AUCi/AUCg), but lower ADI index as compared with healthy subjects. Partial correlation analysis in all populations showed that the M-value was significantly negatively correlated with HOMA-IR, TyG, TG/HDL, and AUCi/AUCg, and correlated positively with the ADI index. The r value of Pearson correlation between the ADI index and M-value was greater than that of the correlation between HOMA-IR, TyG, TG/HDL-C, and AUCi/AUCg. The optimal cut-off value of the ADI index for detection of IR was 0.67, with a sensitivity of 89.4% and a specificity of 88.1%, whereas for detection of MetS, it was 0.32, with a sensitivity of 88.7% and a specificity of 71.0%. The ADI index may be a surrogate marker in detecting IR and MetS. PMID:27930544

Indexing Learning Objects: Vocabularies and Empirical Investigation of Consistency

ERIC Educational Resources Information Center

Kabel, Suzanne; De Hoog, Robert; Wielinga, Bob; Anjewierden, Anjo

2004-01-01

In addition to the LOM standard and instructional design specifications, as well as domain specific indexing vocabularies, a structured indexing vocabulary for the more elementary learning objects is advisable in order to support retrieval tasks of developers. Furthermore, because semantic indexing is seen as a difficult task, three issues…

A comparison of the recording of comorbidity in primary and secondary care by using the Charlson Index to predict short-term and long-term survival in a routine linked data cohort.

PubMed

Crooks, C J; West, J; Card, T R

2015-06-05

Hospital admission records provide snapshots of clinical histories for a subset of the population admitted to hospital. In contrast, primary care records provide continuous clinical histories for complete populations, but might lack detail about inpatient stays. Therefore, combining primary and secondary care records should improve the ability of comorbidity scores to predict survival in population-based studies, and provide better adjustment for case-mix differences when assessing mortality outcomes. Cohort study. English primary and secondary care 1 January 2005 to 1 January 2010. All patients 20 years and older registered to a primary care practice contributing to the linked Clinical Practice Research Datalink from England. The performance of the Charlson index with mortality was compared when derived from either primary or secondary care data or both. This was assessed in relation to short-term and long-term survival, age, consultation rate, and specific acute and chronic diseases. 657,264 people were followed up from 1 January 2005. Although primary care recorded more comorbidity than secondary care, the resulting C statistics for the Charlson index remained similar: 0.86 and 0.87, respectively. Higher consultation rates and restricted age bands reduced the performance of the Charlson index, but the index's excellent performance persisted over longer follow-up; the C statistic was 0.87 over 1 year, and 0.85 over all 5 years of follow-up. The Charlson index derived from secondary care comorbidity had a greater effect than primary care comorbidity in reducing the association of upper gastrointestinal bleeding with mortality. However, they had a similar effect in reducing the association of diabetes with mortality. These findings support the use of the Charlson index from linked data and show that secondary care comorbidity coding performed at least as well as that derived from primary care in predicting survival. 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.

Monitoring task loading with multivariate EEG measures during complex forms of human-computer interaction

NASA Technical Reports Server (NTRS)

Smith, M. E.; Gevins, A.; Brown, H.; Karnik, A.; Du, R.

2001-01-01

Electroencephalographic (EEG) recordings were made while 16 participants performed versions of a personal-computer-based flight simulation task of low, moderate, or high difficulty. As task difficulty increased, frontal midline theta EEG activity increased and alpha band activity decreased. A participant-specific function that combined multiple EEG features to create a single load index was derived from a sample of each participant's data and then applied to new test data from that participant. Index values were computed for every 4 s of task data. Across participants, mean task load index values increased systematically with increasing task difficulty and differed significantly between the different task versions. Actual or potential applications of this research include the use of multivariate EEG-based methods to monitor task loading during naturalistic computer-based work.

Impact of body mass index on mortality and hospitalisation of patients with atrial fibrillation.

PubMed

Ball, Jocasta; Løchen, Maja-Lisa; Carrington, Melinda J; Wiley, Joshua F; Stewart, Simon

2018-04-01

Atrial fibrillation represents a substantial clinical and public health issue. The definitive impact of body mass index on prognosis of patients with chronic (persistent or permanent) atrial fibrillation remains undetermined. The purpose of this study was to investigate the association of body mass index with health outcomes (mortality and re-hospitalisation) of patients with chronic atrial fibrillation. Using data from the Standard versus Atrial Fibrillation spEcific managemenT strategY (SAFETY) trial (a randomised controlled trial of home-based, atrial fibrillation-specific disease management), we performed post-hoc analyses of mortality and re-hospitalisation outcomes during minimum 24-month follow-up according to baseline body mass index profile. Of 297 participants (mean age 71±11 years, 47% female, mean body mass index 29.6±6.7 kg/m 2 ), 35.0% of participants were overweight (body mass index 25.0-29.9 kg/m 2 ) and 43.1% were obese (body mass index≥30 kg/m 2 ). During follow-up, n=42 died including 16/65 (24.6%) classified as normal body mass index, 16/104 (15.4%) classified as overweight and 10/128 (7.8%) classified as obese. Increasing body mass index was not associated with increased mortality but was associated with re-hospitalisation due to cardiovascular disease with greater length-of-stay (odds ratio 1.05; 95% confidence interval 1.00-1.09, p=0.032). Obese individuals experienced increased unplanned admissions compared to overweight individuals (incidence rate ratio 0.71; 95% confidence interval 0.53-0.96, p=0.028), and increased cardiovascular-related (incidence rate ratio 0.58; 95% confidence interval 0.39-0.86, p=0.007) and all-cause admissions (incidence rate ratio 0.63; 95% confidence interval 0.45-0.89, p=0.008) compared to those classified as normal body mass index. Overweight and obesity were not associated with survival in patients with chronic atrial fibrillation but were associated with more frequent hospital care and prolonged stay.

Noncredible cognitive performance at clinical evaluation of adult ADHD: An embedded validity indicator in a visuospatial working memory test.

PubMed

Fuermaier, Anselm B M; Tucha, Oliver; Koerts, Janneke; Lange, Klaus W; Weisbrod, Matthias; Aschenbrenner, Steffen; Tucha, Lara

2017-12-01

The assessment of performance validity is an essential part of the neuropsychological evaluation of adults with attention-deficit/hyperactivity disorder (ADHD). Most available tools, however, are inaccurate regarding the identification of noncredible performance. This study describes the development of a visuospatial working memory test, including a validity indicator for noncredible cognitive performance of adults with ADHD. Visuospatial working memory of adults with ADHD (n = 48) was first compared to the test performance of healthy individuals (n = 48). Furthermore, a simulation design was performed including 252 individuals who were randomly assigned to either a control group (n = 48) or to 1 of 3 simulation groups who were requested to feign ADHD (n = 204). Additional samples of 27 adults with ADHD and 69 instructed simulators were included to cross-validate findings from the first samples. Adults with ADHD showed impaired visuospatial working memory performance of medium size as compared to healthy individuals. Simulation groups committed significantly more errors and had shorter response times as compared to patients with ADHD. Moreover, binary logistic regression analysis was carried out to derive a validity index that optimally differentiates between true and feigned ADHD. ROC analysis demonstrated high classification rates of the validity index, as shown in excellent specificity (95.8%) and adequate sensitivity (60.3%). The visuospatial working memory test as presented in this study therefore appears sensitive in indicating cognitive impairment of adults with ADHD. Furthermore, the embedded validity index revealed promising results concerning the detection of noncredible cognitive performance of adults with ADHD. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

41 CFR 101-29.216 - Department of Defense Index of Specifications and Standards (DODISS).

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Department of Defense... Defense Index of Specifications and Standards (DODISS). The Department of Defense Index of Specifications and Standards is a Department of Defense (DoD) publication of unclassified Federal and military...

41 CFR 101-29.216 - Department of Defense Index of Specifications and Standards (DODISS).

Code of Federal Regulations, 2014 CFR

2014-07-01

... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true Department of Defense... Defense Index of Specifications and Standards (DODISS). The Department of Defense Index of Specifications and Standards is a Department of Defense (DoD) publication of unclassified Federal and military...

41 CFR 101-29.216 - Department of Defense Index of Specifications and Standards (DODISS).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 41 Public Contracts and Property Management 2 2011-07-01 2007-07-01 true Department of Defense... Defense Index of Specifications and Standards (DODISS). The Department of Defense Index of Specifications and Standards is a Department of Defense (DoD) publication of unclassified Federal and military...

41 CFR 101-29.216 - Department of Defense Index of Specifications and Standards (DODISS).

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true Department of Defense... Defense Index of Specifications and Standards (DODISS). The Department of Defense Index of Specifications and Standards is a Department of Defense (DoD) publication of unclassified Federal and military...

41 CFR 101-29.216 - Department of Defense Index of Specifications and Standards (DODISS).

Code of Federal Regulations, 2012 CFR

2012-07-01

... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false Department of Defense... Defense Index of Specifications and Standards (DODISS). The Department of Defense Index of Specifications and Standards is a Department of Defense (DoD) publication of unclassified Federal and military...

Measurement of health system performance at district level: A study protocol.

PubMed

Sharma, Atul; Prinja, Shankar; Aggarwal, Arun Kumar

2017-12-13

Limited efforts have been observed in low and middle income countries to undertake health system performance assessment at district level. Absence of a comprehensive data collection tool and lack of a standardised single summary measure defining overall performance are some of the main problems. Present study has been undertaken to develop a summary composite health system performance index at district level. A broad range of indicators covering all six domains as per building block framework were finalized by an expert panel. The domains were classified into twenty sub-domains, with 70 input and process indicators to measure performance. Seven sub-domains for assessing health system outputs and outcomes were identified, with a total of 28 indicators. Districts in Haryana state from north India were selected for the study. Primary and secondary data will be collected from 378 health facilities, district and state health directorate headquarters. Indicators will be normalized, aggregated to generate composite performance index at district level. Domain specific scores will present the quality of individual building block domains in the public health system. Robustness of the results will be checked using sensitivity analysis. The study presents a methodology for comprehensive assessment of all health system domains on basis of input, process, output and outcome indicators which has never been reported from India. Generation of this index will help identify policy and implementation areas of concern and point towards potential solutions. Results may also help understand relationships between individual building blocks and their sub-components.

A novel clinical index for the assessment of RVD in acute pulmonary embolism: Blood pressure index.

PubMed

Ates, Hale; Ates, Ihsan; Kundi, Harun; Arikan, Mehmet Fettah; Yilmaz, Fatma Meric

2017-10-01

This study aims to investigate the role of the blood pressure index (BPI), which is a new index that we developed, in detection of right ventricular dysfunction (RVD) in acute pulmonary embolism (APE). A total of 539 patients, (253 males and 286 females), diagnosed with APE using computer tomography pulmonary angiography were included in the study. The BPI was obtained by dividing systolic blood pressure (SBP) by diastolic blood pressure (DBP). Mean DBP (75±11mmHg vs 63±15mmHg; p<0.001, respectively) was found to be higher in RVD patients compared to those without RVD, whereas BPI (1.5±0.1 vs 1.9±0.2; p<0.001, respectively) was lower. Examining the performance of BPI in prediction of RVD using receiver operating characteristic curve analysis (area under curve±SE=0.975±0.006; p<0.001), it was found that BPI could predict RVD with very high sensitivity (92.8%) and specificity (100%) and had a positive predictive value of 100% and a negative predictive value of 42.1%. According to the analysis, the highest youden index for the optimal prediction value was found to be 0.478 and the BPI≤1.4 was found to predict mortality 68.6% sensitivity and 80.8% specificity (Area under curve±SE=0.777±0.051; p<0.001). We found that BPI was an index with high positive predictive value and low negative predictive value in detection of RVD. Copyright © 2017 Elsevier Inc. All rights reserved.

Freezing of Gait Detection in Parkinson's Disease: A Subject-Independent Detector Using Anomaly Scores.

PubMed

Pham, Thuy T; Moore, Steven T; Lewis, Simon John Geoffrey; Nguyen, Diep N; Dutkiewicz, Eryk; Fuglevand, Andrew J; McEwan, Alistair L; Leong, Philip H W

2017-11-01

Freezing of gait (FoG) is common in Parkinsonian gait and strongly relates to falls. Current clinical FoG assessments are patients' self-report diaries and experts' manual video analysis. Both are subjective and yield moderate reliability. Existing detection algorithms have been predominantly designed in subject-dependent settings. In this paper, we aim to develop an automated FoG detector for subject independent. After extracting highly relevant features, we apply anomaly detection techniques to detect FoG events. Specifically, feature selection is performed using correlation and clusterability metrics. From a list of 244 feature candidates, 36 candidates were selected using saliency and robustness criteria. We develop an anomaly score detector with adaptive thresholding to identify FoG events. Then, using accuracy metrics, we reduce the feature list to seven candidates. Our novel multichannel freezing index was the most selective across all window sizes, achieving sensitivity (specificity) of (). On the other hand, freezing index from the vertical axis was the best choice for a single input, achieving sensitivity (specificity) of () for ankle and () for back sensors. Our subject-independent method is not only significantly more accurate than those previously reported, but also uses a much smaller window (e.g., versus ) and/or lower tolerance (e.g., versus ).Freezing of gait (FoG) is common in Parkinsonian gait and strongly relates to falls. Current clinical FoG assessments are patients' self-report diaries and experts' manual video analysis. Both are subjective and yield moderate reliability. Existing detection algorithms have been predominantly designed in subject-dependent settings. In this paper, we aim to develop an automated FoG detector for subject independent. After extracting highly relevant features, we apply anomaly detection techniques to detect FoG events. Specifically, feature selection is performed using correlation and clusterability metrics. From a list of 244 feature candidates, 36 candidates were selected using saliency and robustness criteria. We develop an anomaly score detector with adaptive thresholding to identify FoG events. Then, using accuracy metrics, we reduce the feature list to seven candidates. Our novel multichannel freezing index was the most selective across all window sizes, achieving sensitivity (specificity) of (). On the other hand, freezing index from the vertical axis was the best choice for a single input, achieving sensitivity (specificity) of () for ankle and () for back sensors. Our subject-independent method is not only significantly more accurate than those previously reported, but also uses a much smaller window (e.g., versus ) and/or lower tolerance (e.g., versus ).

Association between power law coefficients of the anatomical noise power spectrum and lesion detectability in breast imaging modalities

NASA Astrophysics Data System (ADS)

Chen, Lin; Abbey, Craig K.; Boone, John M.

2013-03-01

Previous research has demonstrated that a parameter extracted from a power function fit to the anatomical noise power spectrum, β, may be predictive of breast mass lesion detectability in x-ray based medical images of the breast. In this investigation, the value of β was compared with a number of other more widely used parameters, in order to determine the relationship between β and these other parameters. This study made use of breast CT data sets, acquired on two breast CT systems developed in our laboratory. A total of 185 breast data sets in 183 women were used, and only the unaffected breast was used (where no lesion was suspected). The anatomical noise power spectrum computed from two-dimensional region of interests (ROIs), was fit to a power function (NPS(f) = α f-β), and the exponent parameter (β) was determined using log/log linear regression. Breast density for each of the volume data sets was characterized in previous work. The breast CT data sets analyzed in this study were part of a previous study which evaluated the receiver operating characteristic (ROC) curve performance using simulated spherical lesions and a pre-whitened matched filter computer observer. This ROC information was used to compute the detectability index as well as the sensitivity at 95% specificity. The fractal dimension was computed from the same ROIs which were used for the assessment of β. The value of β was compared to breast density, detectability index, sensitivity, and fractal dimension, and the slope of these relationships was investigated to assess statistical significance from zero slope. A statistically significant non-zero slope was considered to be a positive association in this investigation. All comparisons between β and breast density, detectability index, sensitivity at 95% specificity, and fractal dimension demonstrated statistically significant association with p < 0.001 in all cases. The value of β was also found to be associated with patient age and breast diameter, parameters both related to breast density. In all associations between other parameters, lower values of β were associated with increased breast cancer detection performance. Specifically, lower values of β were associated with lower breast density, higher detectability index, higher sensitivity, and lower fractal dimension values. While causality was not and probably cannot be demonstrated, the strong, statistically significant association between the β metric and the other more widely used parameters suggest that β may be considered as a surrogate measure for breast cancer detection performance. These findings are specific to breast parenchymal patterns and mass lesions only.

Material-specific difficulties in episodic memory tasks in mild traumatic brain injury.

PubMed

Tsirka, Vassiliki; Simos, Panagiotis; Vakis, Antonios; Vourkas, Michael; Arzoglou, Vasileios; Syrmos, Nikolaos; Stavropoulos, Stavros; Micheloyannis, Sifis

2010-03-01

The study examines acute, material-specific secondary memory performance in 26 patients with mild traumatic brain injury (MTBI) and 26 healthy controls, matched on demographic variables and indexes of crystallized intelligence. Neuropsychological tests were used to evaluate primary and secondary memory, executive functions, and verbal fluency. Participants were also tested on episodic memory tasks involving words, pseudowords, pictures of common objects, and abstract kaleidoscopic images. Patients showed reduced performance on episodic memory measures, and on tasks associated with visuospatial processing and executive function (Trail Making Test part B, semantic fluency). Significant differences between groups were also noted for correct rejections and response bias on the kaleidoscope task. MTBI patients' reduced performance on memory tasks for complex, abstract stimuli can be attributed to a dysfunction in the strategic component of memory process.

Holistic rubric vs. analytic rubric for measuring clinical performance levels in medical students.

PubMed

Yune, So Jung; Lee, Sang Yeoup; Im, Sun Ju; Kam, Bee Sung; Baek, Sun Yong

2018-06-05

Task-specific checklists, holistic rubrics, and analytic rubrics are often used for performance assessments. We examined what factors evaluators consider important in holistic scoring of clinical performance assessment, and compared the usefulness of applying holistic and analytic rubrics respectively, and analytic rubrics in addition to task-specific checklists based on traditional standards. We compared the usefulness of a holistic rubric versus an analytic rubric in effectively measuring the clinical skill performances of 126 third-year medical students who participated in a clinical performance assessment conducted by Pusan National University School of Medicine. We conducted a questionnaire survey of 37 evaluators who used all three evaluation methods-holistic rubric, analytic rubric, and task-specific checklist-for each student. The relationship between the scores on the three evaluation methods was analyzed using Pearson's correlation. Inter-rater agreement was analyzed by Kappa index. The effect of holistic and analytic rubric scores on the task-specific checklist score was analyzed using multiple regression analysis. Evaluators perceived accuracy and proficiency to be major factors in objective structured clinical examinations evaluation, and history taking and physical examination to be major factors in clinical performance examinations evaluation. Holistic rubric scores were highly related to the scores of the task-specific checklist and analytic rubric. Relatively low agreement was found in clinical performance examinations compared to objective structured clinical examinations. Meanwhile, the holistic and analytic rubric scores explained 59.1% of the task-specific checklist score in objective structured clinical examinations and 51.6% in clinical performance examinations. The results show the usefulness of holistic and analytic rubrics in clinical performance assessment, which can be used in conjunction with task-specific checklists for more efficient evaluation.

Individual differences and specificity of prefrontal gamma frequency-tACS on fluid intelligence capabilities.

PubMed

Santarnecchi, E; Muller, T; Rossi, S; Sarkar, A; Polizzotto, N R; Rossi, A; Cohen Kadosh, R

2016-02-01

Emerging evidence suggests that transcranial alternating current stimulation (tACS) is an effective, frequency-specific modulator of endogenous brain oscillations, with the potential to alter cognitive performance. Here, we show that reduction in response latencies to solve complex logic problem indexing fluid intelligence is obtained through 40 Hz-tACS (gamma band) applied to the prefrontal cortex. This improvement in human performance depends on individual ability, with slower performers at baseline receiving greater benefits. The effect could have not being explained by regression to the mean, and showed task and frequency specificity: it was not observed for trials not involving logical reasoning, as well as with the application of low frequency 5 Hz-tACS (theta band) or non-periodic high frequency random noise stimulation (101-640 Hz). Moreover, performance in a spatial working memory task was not affected by brain stimulation, excluding possible effects on fluid intelligence enhancement through an increase in memory performance. We suggest that such high-level cognitive functions are dissociable by frequency-specific neuromodulatory effects, possibly related to entrainment of specific brain rhythms. We conclude that individual differences in cognitive abilities, due to acquired or developmental origins, could be reduced during frequency-specific tACS, a finding that should be taken into account for future individual cognitive rehabilitation studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bispectral index to predict neurological outcome early after cardiac arrest.

PubMed

Stammet, Pascal; Collignon, Olivier; Werer, Christophe; Sertznig, Claude; Devaux, Yvan

2014-12-01

To address the value of continuous monitoring of bispectral index (BIS) to predict neurological outcome after cardiac arrest. In this prospective observational study in adult comatose patients treated by therapeutic hypothermia after cardiac arrest we measured bispectral index (BIS) during the first 24 hours of intensive care unit stay. A blinded neurological outcome assessment by cerebral performance category (CPC) was done 6 months after cardiac arrest. Forty-six patients (48%) had a good neurological outcome at 6-month, as defined by a cerebral performance category (CPC) 1-2, and 50 patients (52%) had a poor neurological outcome (CPC 3-5). Over the 24h of monitoring, mean BIS values over time were higher in the good outcome group (38 ± 9) compared to the poor outcome group (17 ± 12) (p<0.001). Analysis of BIS recorded every 30 minutes provided an optimal prediction after 12.5h, with an area under the receiver operating characteristic curve (AUC) of 0.89, a specificity of 89% and a sensitivity of 86% using a cut-off value of 23. With a specificity fixed at 100% (sensitivity 26%) the cut-off BIS value was 2.4 over the first 271 minutes. In multivariable analyses including clinical characteristics, mean BIS value over the first 12.5h was a predictor of neurological outcome (p = 6E-6) and provided a continuous net reclassification index of 1.28% (p = 4E-10) and an integrated discrimination improvement of 0.31 (p=1E-10). Mean BIS value calculated over the first 12.5h after ICU admission potentially predicts 6-months neurological outcome after cardiac arrest. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Sleep and Cognitive Function in Multiple Sclerosis.

PubMed

Braley, Tiffany J; Kratz, Anna L; Kaplish, Neeraj; Chervin, Ronald D

2016-08-01

To examine associations between cognitive performance and polysomnographic measures of obstructive sleep apnea in patients with multiple sclerosis (MS). Participants underwent a comprehensive MS-specific cognitive testing battery (the Minimal Assessment of Cognitive Function in MS, or MACFIMS) and in-laboratory overnight PSG. In adjusted linear regression models, the oxygen desaturation index (ODI) and minimum oxygen saturation (MinO2) were significantly associated with performance on multiple MACFIMS measures, including the Paced Auditory Serial Addition Test (PASAT; 2-sec and 3-sec versions), which assesses working memory, processing speed, and attention, and on the Brief Visuospatial Memory Test-Revised, a test of delayed visual memory. The respiratory disturbance index (RDI) was also significantly associated with PASAT-3 scores as well as the California Verbal Learning Test-II (CVLT-II) Discriminability Index, a test of verbal memory and response inhibition. Among these associations, apnea severity measures accounted for between 12% and 23% of the variance in cognitive test performance. Polysomnographic measures of sleep fragmentation (as reflected by the total arousal index) and total sleep time also showed significant associations with a component of the CVLT-II that assesses response inhibition, explaining 18% and 27% of the variance in performance. Among patients with MS, obstructive sleep apnea and sleep disturbance are significantly associated with diminished visual memory, verbal memory, executive function (as reflected by response inhibition), attention, processing speed, and working memory. If sleep disorders degrade these cognitive functions, effective treatment could offer new opportunities to improve cognitive functioning in patients with MS. A commentary on this article appears in this issue on page 1489. © 2016 Associated Professional Sleep Societies, LLC.

40 CFR 65.63 - Performance and group status change requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... material or TOC by at least 98 weight-percent or to a concentration of less than 20 parts per million by... recalculate the TRE index value, flow, or TOC or organic hazardous air pollutant (HAP) concentration according.... Engineering assessments shall meet the specifications in § 65.64(i). (2) Concentration. The TOC or organic HAP...

Sleep and Cognition in Preschool Years: Specific Links to Executive Functioning

ERIC Educational Resources Information Center

Bernier, Annie; Beauchamp, Miriam H.; Bouvette-Turcot, Andrée-Anne; Carlson, Stephanie M.; Carrier, Julie

2013-01-01

This study investigated the prospective links between sleep in infancy and preschoolers' cognitive performance. Mothers of 65 infants completed a sleep diary when infants were aged 1 year, and children completed two subscales of the Wechsler Preschool and Primary Scale of Intelligence at 4 years, indexing general cognitive ability and complex…

A Prospectus to Study the Effect of High School Academic Performance Index on University Eligibility. Working Paper WP/05-06

ERIC Educational Resources Information Center

California Postsecondary Education Commission, 2005

2005-01-01

The California Postsecondary Education Commission periodically conducts studies of university eligibility of public high school graduates. The eligibility rates from these studies are the proportion of high school graduates who qualify for freshman admission to California public universities. Eligibility is based on completion of specific high…

Reactivity to Stress and the Cognitive Components of Math Disability in Grade 1 Children

ERIC Educational Resources Information Center

MacKinnon McQuarrie, Maureen A.; Siegel, Linda S.; Perry, Nancy E.; Weinberg, Joanne

2014-01-01

This study investigated the relationship among working memory, processing speed, math performance, and reactivity to stress in 83 Grade 1 children. Specifically, 39 children with math disability (MD) were compared to 44 children who are typically achieving (TA) in mathematics. It is the first study to use a physiological index of stress (salivary…

What Are Standardized Literacy and Numeracy Tests Testing? Evidence of the Domain-General Contributions to Students' Standardized Educational Test Performance

ERIC Educational Resources Information Center

Howard, Steven J.; Woodcock, Stuart; Ehrich, John; Bokosmaty, Sahar

2017-01-01

Background: A fundamental aim of standardized educational assessment is to achieve reliable discrimination between students differing in the knowledge, skills and abilities assessed. However, questions of the purity with which these tests index students' genuine abilities have arisen. Specifically, literacy and numeracy assessments may also engage…

Diagnostic efficiency of Mueller-matrix polarization reconstruction system of the phase structure of liver tissue

NASA Astrophysics Data System (ADS)

Zabolotna, Natalia I.; Pavlov, Sergii V.; Radchenko, Kostiantyn O.; Stasenko, Vladyslav A.; Wójcik, Waldemar; Kussambayeva, Nazym

2015-12-01

The application field of using the Mueller-matrix polarizing reconstruction system of phase structure of biological layer for optical-anisotropic parameters differentiation of histological sections of healthy and rat's liver with hepatitis were investigated. Comparison of system informativity with known systems on indexes of sensitivity, specificity and balanced accuracy were performed.

Demirjian's stages and Cameriere's third molar maturity index to estimate legal adult age in Peruvian population.

PubMed

Quispe Lizarbe, Roselhy Juliana; Solís Adrianzén, Christian; Quezada-Márquez, Milushka Miroslava; Galić, Ivan; Cameriere, Roberto

2017-03-01

To compare the accuracy of Demirjian's stages (DS) and Cameriere's third molar maturity index cut-off value (I 3M <0.08) to estimate the age of majority on panoramic radiographs (OPTs) from the dental clinic of the Scientific University of the South (UCSUR), Lima, Peru. An observational cross-sectional study was conducted on the sample of 208 digital panoramic radiographs of patients aged 14-22years examined during 2015 in UCSUR. The left lower third molars were analyzed using Adobe Photoshop® CS6. An effectiveness of specific DS and I 3M <0.08 was evaluated by using accurate classification, sensitivity, specificity, positive (LR+) and negative (LR-) likelihood ratios and Bayes post-test probability (p). Only G and H stages were practical for classify adults and minors in the tested sample, while I 3M <0.08 showed the best performance in both sexes. For I 3M <0.08, the accurate classification, sensitivity and specificity were 0.96, 0.96, 0.96 and 0.90, 0.84 and 0.95 in males and females, respectively. Values of LR+, LR- and p were 24.96, 0.04, 0.97 and 15.68, 0.17, 0.95 in males and females, respectively. The specific cut-off value of third molar maturity index (I 3M <0.08) showed to be more accurate in discriminating adults and minors in Peruvian sample when a test with high sensitivity and specificity is required. Copyright © 2017 Elsevier B.V. All rights reserved.

Obesity in Korean pre-adolescent school children: comparison of various anthropometric measurements based on bioelectrical impedance analysis.

PubMed

Yoo, S; Lee, S-Y; Kim, K-N; Sung, E

2006-07-01

To examine the relationships between body mass index (BMI), percentage-weight-for-height (PWH) and percentage body fat (PBF), and to compare their validity based on PBF with the BMI criteria of International Obesity Task Force (IOTF) for childhood obesity in Korean pre-adolescent school children. Statistical comparative analysis for anthropometric measures. Korean pre-adolescent children (438 boys and 454 girls, aged 8-12 years, mean BMI 19.5+/-3.4 kg/m2). Body mass index and PWH were calculated as body size indices from height and weight. Hand-to-foot bioelectrical impedance analysis (BIA) was performed to obtain PBF values, with obese children defined as PBF above 35%. Sensitivity and specificity were displayed with the gold standard of PBF, and receiver operating characteristic (ROC) curves were used to assess the performance of BMI and PWH in detecting obesity. The prevalence of obesity varied by the criteria: 18.8% by Korean BMI standards for 95 percentile, 11% by the IOTF-BMI 30 kg/m2 and 29.4% by Korean PWH cutoffs. Body mass index and PWH were significantly correlated with PBF after adjusting for age, 0.910 (P<0.01) and 0.915 (P<0.01), respectively. The sensitivity and specificity of the PWH cutoffs were 0.909 and 0.882, respectively. The local BMI 95 percentiles had lower sensitivity (0.714) and specificity (0.790). The IOTF-BMI definition showed much lower sensitivity (0.457) and higher specificity (0.990). The BMI cutoffs corresponding with the highest accuracy were smaller than IOTF-BMI 30 kg/m2 for all age groups in both boys and girls. The prevalence of obesity among Korean pre-adolescent children widely varied according to the diagnostic criteria applied. Universally recommended cutoffs for children by IOTF showed the lowest sensitivity among the criteria used, and may therefore underestimate obesity in this population.

Plantar fascia-specific stretching versus radial shock-wave therapy as initial treatment of plantar fasciopathy.

PubMed

Rompe, Jan D; Cacchio, Angelo; Weil, Lowell; Furia, John P; Haist, Joachim; Reiners, Volker; Schmitz, Christoph; Maffulli, Nicola

2010-11-03

Whether plantar fascia-specific stretching or shock-wave therapy is effective as an initial treatment for proximal plantar fasciopathy remains unclear. The aim of this study was to test the null hypothesis of no difference in the effectiveness of these two forms of treatment for patients who had unilateral plantar fasciopathy for a maximum duration of six weeks and which had not been treated previously. One hundred and two patients with acute plantar fasciopathy were randomly assigned to perform an eight-week plantar fascia-specific stretching program (Group I, n = 54) or to receive repetitive low-energy radial shock-wave therapy without local anesthesia, administered weekly for three weeks (Group II, n = 48). All patients completed the seven-item pain subscale of the validated Foot Function Index and a patient-relevant outcome questionnaire. Patients were evaluated at baseline and at two, four, and fifteen months after baseline. The primary outcome measures were a mean change in the Foot Function Index sum score at two months after baseline, a mean change in item 2 (pain during the first few steps of walking in the morning) on this index, and satisfaction with treatment. No difference in mean age, sex, weight, or duration of symptoms was found between the groups at baseline. At two months after baseline, the Foot Function Index sum score showed significantly greater changes for the patients managed with plantar fascia-specific stretching than for those managed with shock-wave therapy (p < 0.001), as well as individually for item 2 (p = 0.002). Thirty-five patients (65%) in Group I versus fourteen patients (29%) in Group II were satisfied with the treatment (p < 0.001). These findings persisted at four months. At fifteen months after baseline, no significant between-group difference was measured. A program of manual stretching exercises specific to the plantar fascia is superior to repetitive low-energy radial shock-wave therapy for the treatment of acute symptoms of proximal plantar fasciopathy.

Oral diseases associated with condition-specific oral health-related quality of life and school performance of Thai primary school children: A hierarchical approach.

PubMed

Kaewkamnerdpong, Issarapong; Krisdapong, Sudaduang

2018-06-01

To assess the hierarchical associations between children's school performance and condition-specific (CS) oral health-related quality of life (OHRQoL), school absence, oral status, sociodemographic and economic status (SDES) and social capital; and to investigate the associations between CS OHRQoL and related oral status, adjusting for SDES and social capital. Data on 925 sixth grade children in Sakaeo province, Thailand, were collected through oral examinations for dental caries and oral hygiene, social capital questionnaires, OHRQoL interviews using the Child-Oral Impacts on Daily Performances index, parental self-administered questionnaires and school documents. A hierarchical conceptual framework was developed, and independent variables were hierarchically entered into multiple logistic models for CS OHRQoL and linear regression models for school performance. After adjusting for SDES and social capital, children with high DMFT or DT scores were significantly threefold more likely to have CS impacts attributed to dental caries. However, poor oral hygiene was not significantly associated with CS impacts attributed to gingival disease. High DMFT scores were significantly associated with lower school performance, whereas high Simplified Oral Hygiene Index scores were not. The final model showed that CS impacts attributed to dental caries and school absence accounted for the association between DMFT score and school performance. Dental caries was associated with CS impacts on OHRQoL, and exerted its effect on school performance through the CS impacts and school absence. There was no association between oral hygiene and CS impacts on OHRQoL or school performance. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Relationship between the refractive index and specific gravity of the rat urine (author's transl)].

PubMed

Kitagawa, Y F; Takahashi, T; Hayashi, H

1981-07-01

The relationship between the refractive index and specific gravity of urine was studied with specimens from 165 Sprague-Dawley rats, by graphic analysis of the plot of the refractometrically determined index against the specific gravity which was measured with a pycnometer. 1. A linear regression was demonstrated between the refractive index and specific gravity. 2. The nomogram fitted the data of even those samples with high refractive index and specific gravity, irrespective of changes in food or water intake and protein or glucose contents in the urine. 3. The nomogram was in good agreement, in respect of linearity, with the regression line derived from the conversion table of TS meter by the American Optical Corporation and also with the nomogram of the Japanese Society of Clinical Pathology. It approximated more closely to the former than to the latter.

Measurement of wall thickness alone does not accurately assess the presence of left ventricular hypertrophy.

PubMed

Leibowitz, David; Planer, David; Ben-Ibgi, Fanny; Rott, David; Weiss, A Teddy; Bursztyn, Michael

2007-02-01

Clinical echocardiographic assessment of left ventricular hypertrophy (LVH) is generally performed by measuring wall thickness alone (WT). The objective of this study was to compare the assessment of LVH using the measurement of WT to that using indexed LV mass. Hypertensive patients underwent echocardiography with the measurement of LV WT and LV mass. For each patient, the presence of LVH was assessed by both methods with WT compared to the gold standard of LV mass index. In all, 92 patients (51M/41F) were entered, and in only 55 patients (60%) were the two methods concordant. There was a tendency for WT to underestimate LVH in females (sensitivity 37%, specificity 79%) and overestimate LVH in males (sensitivity 88%, specificity 56%). The measurement of WT alone overestimates LVH in males and underestimates LVH in females and should not be used as a surrogate marker for increased LV mass.

Support Vector Machines to improve physiologic hot flash measures: application to the ambulatory setting.

PubMed

Thurston, Rebecca C; Hernandez, Javier; Del Rio, Jose M; De La Torre, Fernando

2011-07-01

Most midlife women have hot flashes. The conventional criterion (≥2 μmho rise/30 s) for classifying hot flashes physiologically has shown poor performance. We improved this performance in the laboratory with Support Vector Machines (SVMs), a pattern classification method. We aimed to compare conventional to SVM methods to classify hot flashes in the ambulatory setting. Thirty-one women with hot flashes underwent 24 h of ambulatory sternal skin conductance monitoring. Hot flashes were quantified with conventional (≥2 μmho/30 s) and SVM methods. Conventional methods had low sensitivity (sensitivity=.57, specificity=.98, positive predictive value (PPV)=.91, negative predictive value (NPV)=.90, F1=.60), with performance lower with higher body mass index (BMI). SVMs improved this performance (sensitivity=.87, specificity=.97, PPV=.90, NPV=.96, F1=.88) and reduced BMI variation. SVMs can improve ambulatory physiologic hot flash measures. Copyright © 2010 Society for Psychophysiological Research.

Cognitive psychopathology in Schizophrenia: Comparing memory performances with Obsessive-compulsive disorder patients and normal subjects on the Wechsler Memory Scale-IV.

PubMed

Cammisuli, Davide Maria; Sportiello, Marco Timpano

2016-06-01

Memory system turns out to be one of the cognitive domains most severely impaired in schizophrenia. Within the theoretical framework of cognitive psychopathology, we compared the performance of schizophrenia patients on the Wechsler Memory Scale-IV with that in matched patients with Obsessive-compulsive disorder and that in healthy control subjects to establish the specific nature of memory deficits in schizophrenia. 30 schizophrenia patients, 30 obsessive-compulsive disorder patients and 40 healthy controls completed the Wechsler Memory Scale-IV. Schizophrenia symptom severity was assessed by the Positive and Negative Syndrome Scale (PANSS). Performances on memory battery including Indexes and subtests scores were compared by a One-Way ANOVA (Scheffé post-hoc test). Spearman Rank correlations were performed between scores on PANSS subscales and symptoms and WMS-IV Indexes and subtests, respectively. Schizophrenia patients showed a memory profile characterized by mild difficulties in auditory memory and visual working memory and poor functioning of visual, immediate and delayed memory. As expected, schizophrenia patients scored lower than healthy controls on all WMS-IV measures. With regard to the WMS-IV Indexes, schizophrenia patients performed worse on Auditory Memory, Visual Memory, Immediate and Delayed Memory than Obsessive-compulsive disorder patients but not on Visual Working Memory. Such a pattern was made even clearer for specific tasks such as immediate and delayed recall and spatial recall and memory for visual details, as revealed by the lowest scores on Logical Memory (immediate and delayed conditions) and Designs (immediate condition) subtests, respectively. Significant negative correlations between Logical Memory I and II were found with PANSS Excitement symptom as well as between DE I and PANSS Tension symptom. Significant positive correlations between LM II and PANSS Blunted affect and Poor rapport symptoms as well as DE I and PANSS Blunted affect and Mannerism and Posturing symptoms, were found too. Memory damage observed in schizophrenia patients was more severe and wider than that of patients with obsessive-compulsive disorder, except for visual working memory. Memory dysfunction, mainly related to episodic memory damage and reduced efficiency of central executive, is intimately connected to the specific psychopathological processes characterizing schizophrenia. Implications for therapeutics and cognitive remediation techniques are discussed.

Index-of-refraction-dependent subcellular light scattering observed with organelle-specific dyes.

PubMed

Wilson, Jeremy D; Cottrell, William J; Foster, Thomas H

2007-01-01

Angularly resolved light scattering and wavelength-resolved darkfield scattering spectroscopy measurements were performed on intact, control EMT6 cells and cells stained with high-extinction lysosomal- or mitochondrial-localizing dyes. In the presence of the lysosomal-localizing dye NPe6, we observe changes in the details of light scattering from stained and unstained cells, which have both wavelength- and angular-dependent features. Analysis of measurements performed at several wavelengths reveals a reduced scattering cross section near the absorption maximum of the lysosomal-localizing dye. When identical measurements are made with cells loaded with a similar mitochondrial-localizing dye, HPPH, we find no evidence that staining mitochondria had any effect on the light scattering. Changes in the scattering properties of candidate populations of organelles induced by the addition of an absorber are modeled with Mie theory, and we find that any absorber-induced scattering response is very sensitive to the inherent refractive index of the organelle population. Our measurements and modeling are consistent with EMT6-cell-mitochondria having refractive indices close to those reported in the literature for organelles, approximately 1.4. The reduction in scattering cross section induced by NPe6 constrains the refractive index of lysosomes to be significantly higher. We estimate the refractive index of lysosomes in EMT6 cells to be approximately 1.6.

[Evaluation of neonatal prognosis using Doppler velocimeter in cases of a high risk fetus].

PubMed

Ferchiou-Cherif, M; Zhioua, F; Hafsia, S; Hamdoun, L; Jedoui, A; Slim, R; Meriah, S

1993-01-01

The authors describe the main characteristics of the Doppler method in the early diagnosis of chronic fetal distress, and report their personal results in the study of 51 high risk pregnancies. In their study the fetal doppler ultrasound findings were correlated with birth weight related to gestational age, and neonatal morbidity. The parameters established from the doppler ultrasound assessment were the placenta resistance (calculated from the formula of Pourcelot: R = S-D/S applied to the umbilical artery) and the cerebro-placental index, Rp/Rc, Rc being the index of cerebral arterial resistance. The diagnosis performance of the method appeared very good: the Rp index was found to be highly specific for hypotrophy (85,7%) and for neonatal morbidity (90%), the RCP index adding its own good sensitivity (85% for hypotrophy and 83,3% for neonatal morbidity). The authors conclude upon the interest to study simultaneously the fetal umbilical and cerebral arterial circulations. The pathological significance of the two indexes appears different so that they are to be complementary in the evaluation of fetal distress.

Evaluation of spatial, radiometric and spectral Thematic Mapper performance for coastal studies

NASA Technical Reports Server (NTRS)

Klemas, V. (Principal Investigator)

1984-01-01

The effect different wetland plant canopies have upon observed reflectance in Thematic Mapper bands is examined. The three major vegetation canopy types (broadleaf, gramineous and leafless) produce unique spectral responses for a similar quantity of live biomass. Biomass estimates computed from spectral data were most similar to biomass estimates determined from harvest data when models developed for a specific canopy were used. Precise determination of regression coefficients for each canopy type and modeling changes in the coefficients with various combinations of canopy types are being tested. The multispectral band scanner vegetation index estimates are very similar to the vegetation index estimates.

Identifying Knowledge Gaps in Clinicians Who Evaluate and Treat Vocal Performing Artists in College Health Settings.

PubMed

McKinnon-Howe, Leah; Dowdall, Jayme

2018-05-01

The goal of this study was to identify knowledge gaps in clinicians who evaluate and treat performing artists for illnesses and injuries that affect vocal function in college health settings. This pilot study utilized a web-based cross-sectional survey design incorporating common clinical scenarios to test knowledge of evaluation and management strategies in the vocal performing artist. A web-based survey was administered to a purposive sample of 28 clinicians to identify the approach utilized to evaluate and treat vocal performing artists in college health settings, and factors that might affect knowledge gaps and influence referral patterns to voice specialists. Twenty-eight clinicians were surveyed, with 36% of respondents incorrectly identifying appropriate vocal hygiene measures, 56% of respondents failing to identify symptoms of vocal fold hemorrhage, 84% failing to identify other indications for referral to a voice specialist, 96% of respondents acknowledging unfamiliarity with the Voice Handicap Index and the Singers Voice Handicap Index, and 68% acknowledging unfamiliarity with the Reflux Symptom Index. The data elucidated specific knowledge gaps in college health providers who are responsible for evaluating and treating common illnesses that affect vocal function, and triaging and referring students experiencing symptoms of potential vocal emergencies. Future work is needed to improve the standard of care for this population. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Surface engineering of hierarchical platinum-cobalt nanowires for efficient electrocatalysis

DOE PAGES

Bu, Lingzheng; Guo, Shaojun; Zhang, Xu; ...

2016-06-29

Despite intense research in past decades, the lack of high-performance catalysts for fuel cell reactions remains a challenge in realizing fuel cell technologies for transportation applications. Here we report a facile strategy for synthesizing hierarchical platinum-cobalt nanowires with high-index, platinum-rich facets and ordered intermetallic structure. These structural features enable unprecedented performance for the oxygen reduction and alcohol oxidation reactions. The specific/mass activities of the platinum-cobalt nanowires for oxygen reduction reaction are 39.6/33.7 times higher than commercial Pt/C catalyst, respectively. Density functional theory simulations reveal that the active threefold hollow sites on the platinum-rich high-index facets provide an additional factor inmore » enhancing oxygen reduction reaction activities. The nanowires are stable in the electrochemical conditions and also thermally stable. Furthermore, this work may represent a key step towards scalable production of high performance platinum-based nanowires for applications in catalysis and energy conversion.« less

A Massively Parallel Computational Method of Reading Index Files for SOAPsnv.

PubMed

Zhu, Xiaoqian; Peng, Shaoliang; Liu, Shaojie; Cui, Yingbo; Gu, Xiang; Gao, Ming; Fang, Lin; Fang, Xiaodong

2015-12-01

SOAPsnv is the software used for identifying the single nucleotide variation in cancer genes. However, its performance is yet to match the massive amount of data to be processed. Experiments reveal that the main performance bottleneck of SOAPsnv software is the pileup algorithm. The original pileup algorithm's I/O process is time-consuming and inefficient to read input files. Moreover, the scalability of the pileup algorithm is also poor. Therefore, we designed a new algorithm, named BamPileup, aiming to improve the performance of sequential read, and the new pileup algorithm implemented a parallel read mode based on index. Using this method, each thread can directly read the data start from a specific position. The results of experiments on the Tianhe-2 supercomputer show that, when reading data in a multi-threaded parallel I/O way, the processing time of algorithm is reduced to 3.9 s and the application program can achieve a speedup up to 100×. Moreover, the scalability of the new algorithm is also satisfying.

Measurement and data processing approach for detecting anisotropic spatial statistics of the turbulence-induced index of refraction fluctuations in the upper atmosphere.

PubMed

Havens, Timothy C; Roggemann, Michael C; Schulz, Timothy J; Brown, Wade W; Beyer, Jeff T; Otten, L John

2002-05-20

We discuss a method of data reduction and analysis that has been developed for a novel experiment to detect anisotropic turbulence in the tropopause and to measure the spatial statistics of these flows. The experimental concept is to make measurements of temperature at 15 points on a hexagonal grid for altitudes from 12,000 to 18,000 m while suspended from a balloon performing a controlled descent. From the temperature data, we estimate the index of refraction and study the spatial statistics of the turbulence-induced index of refraction fluctuations. We present and evaluate the performance of a processing approach to estimate the parameters of an anisotropic model for the spatial power spectrum of the turbulence-induced index of refraction fluctuations. A Gaussian correlation model and a least-squares optimization routine are used to estimate the parameters of the model from the measurements. In addition, we implemented a quick-look algorithm to have a computationally nonintensive way of viewing the autocorrelation function of the index fluctuations. The autocorrelation of the index of refraction fluctuations is binned and interpolated onto a uniform grid from the sparse points that exist in our experiment. This allows the autocorrelation to be viewed with a three-dimensional plot to determine whether anisotropy exists in a specific data slab. Simulation results presented here show that, in the presence of the anticipated levels of measurement noise, the least-squares estimation technique allows turbulence parameters to be estimated with low rms error.

Increased lower limb muscle coactivation reduces gait performance and increases metabolic cost in patients with hereditary spastic paraparesis.

PubMed

Rinaldi, Martina; Ranavolo, Alberto; Conforto, Silvia; Martino, Giovanni; Draicchio, Francesco; Conte, Carmela; Varrecchia, Tiwana; Bini, Fabiano; Casali, Carlo; Pierelli, Francesco; Serrao, Mariano

2017-10-01

The aim of this study was to investigate the lower limb muscle coactivation and its relationship with muscles spasticity, gait performance, and metabolic cost in patients with hereditary spastic paraparesis. Kinematic, kinetic, electromyographic and energetic parameters of 23 patients and 23 controls were evaluated by computerized gait analysis system. We computed ankle and knee antagonist muscle coactivation indexes throughout the gait cycle and during the subphases of gait. Energy consumption and energy recovery were measured as well. In addition to the correlation analysis between coactivation indexes and clinical variables, correlations between coactivation indexes and time-distance, kinematic, kinetic, and energetic parameters were estimated. Increased coactivity indexes of both knee and ankle muscles throughout the gait cycle and during the subphases of gait were observed in patients compared with controls. Energetic parameters were significantly higher in patients than in controls. Both knee and ankle muscle coactivation indexes were positively correlated with knee and ankle spasticity (Ashworth score), respectively. Knee and ankle muscle coactivation indexes were both positively correlated with energy consumption and both negatively correlated with energy recovery. Positive correlations between the Ashworth score and lower limb muscle coactivation suggest that abnormal lower limb muscle coactivation in patients with hereditary spastic paraparesis reflects a primary deficit linked to lower limb spasticity. Furthermore, these abnormalities influence the energetic mechanisms during walking. Identifying excessive muscle coactivation may be helpful in individuating the rehabilitative treatments and designing specific orthosis to restrain spasticity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Neural alpha oscillations index the balance between self-other integration and segregation in real-time joint action.

PubMed

Novembre, Giacomo; Sammler, Daniela; Keller, Peter E

2016-08-01

Shared knowledge and interpersonal coordination are prerequisites for most forms of social behavior. Influential approaches to joint action have conceptualized these capacities in relation to the separate constructs of co-representation (knowledge) and self-other entrainment (coordination). Here we investigated how brain mechanisms involved in co-representation and entrainment interact to support joint action. To do so, we used a musical joint action paradigm to show that the neural mechanisms underlying co-representation and self-other entrainment are linked via a process - indexed by EEG alpha oscillations - regulating the balance between self-other integration and segregation in real time. Pairs of pianists performed short musical items while action familiarity and interpersonal (behavioral) synchronization accuracy were manipulated in a factorial design. Action familiarity referred to whether or not pianists had rehearsed the musical material performed by the other beforehand. Interpersonal synchronization was manipulated via congruent or incongruent tempo change instructions that biased performance timing towards the impending, new tempo. It was observed that, when pianists were familiar with each other's parts, millisecond variations in interpersonal synchronized behavior were associated with a modulation of alpha power over right centro-parietal scalp regions. Specifically, high behavioral entrainment was associated with self-other integration, as indexed by alpha suppression. Conversely, low behavioral entrainment encouraged reliance on internal knowledge and thus led to self-other segregation, indexed by alpha enhancement. These findings suggest that alpha oscillations index the processing of information about self and other depending on the compatibility of internal knowledge and external (environmental) events at finely resolved timescales. Copyright © 2016 Elsevier Ltd. All rights reserved.

Diagnostic accuracy of a noninvasive hepatic ultrasound score for non-alcoholic fatty liver disease (NAFLD) in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

PubMed

Goulart, Alessandra Carvalho; Oliveira, Ilka Regina Souza de; Alencar, Airlane Pereira; Santos, Maira Solange Camara dos; Santos, Itamar Souza; Martines, Brenda Margatho Ramos; Meireles, Danilo Peron; Martines, João Augusto dos Santos; Misciagna, Giovanni; Benseñor, Isabela Martins; Lotufo, Paulo Andrade

2015-01-01

Noninvasive strategies for evaluating non-alcoholic fatty liver disease (NAFLD) have been investigated over the last few decades. Our aim was to evaluate the diagnostic accuracy of a new hepatic ultrasound score for NAFLD in the ELSA-Brasil study. Diagnostic accuracy study conducted in the ELSA center, in the hospital of a public university. Among the 15,105 participants of the ELSA study who were evaluated for NAFLD, 195 individuals were included in this sub-study. Hepatic ultrasound was performed (deep beam attenuation, hepatorenal index and anteroposterior diameter of the right hepatic lobe) and compared with the hepatic steatosis findings from 64-channel high-resolution computed tomography (CT). We also evaluated two clinical indices relating to NAFLD: the fatty liver index (FLI) and the hepatic steatosis index (HSI). Among the 195 participants, the NAFLD frequency was 34.4%. High body mass index, high waist circumference, diabetes and hypertriglyceridemia were associated with high hepatic attenuation and large anteroposterior diameter of the right hepatic lobe, but not with the hepatorenal index. The hepatic ultrasound score, based on hepatic attenuation and the anteroposterior diameter of the right hepatic lobe, presented the best performance for NAFLD screening at the cutoff point ≥ 1 point; sensitivity: 85.1%; specificity: 73.4%; accuracy: 79.3%; and area under the curve (AUC 0.85; 95% confidence interval, CI: 0.78-0.91)]. FLI and HSI presented lower performance (AUC 0.76; 95% CI: 0.69-0.83) than CT. The hepatic ultrasound score based on hepatic attenuation and the anteroposterior diameter of the right hepatic lobe has good reproducibility and accuracy for NAFLD screening.

Toward an objective indexing system for ADHD-screening using children's activity monitoring.

PubMed

Kam, Hye Jin; Choi, Jong Pil; Park, Rae Woong

2008-11-06

Signs of ADHD are discernible in specific situations, and usually assessed according to subjective impressions. We performed a preliminary comparative study from children's activity at a natural classroom environment with 3-axis accelerator for a feasible objective index. From a total of 157 children (7-9 yrs) and clinically diagnosed 24 children out of them, variances in 1-min epoch mean activity had shown significant differences among the subgroups: (1) ADHD=.0194, Other Diseases=.0080, Normal=.0009; (2) ADHD=.0194, non-ADHD=.0057(p<.01, respectively). There were also significant differences in high-level activity (>1.6G) features among subgroups with the same order (p<.01, respectively). ADHD patients exhibited more dispersed activities and higher high-level activity ratio than normal. Activity features can be useful to build an objective indexing system for screening ADHD patients.

An Additive Definition of Molecular Complexity.

PubMed

Böttcher, Thomas

2016-03-28

A framework for molecular complexity is established that is based on information theory and consistent with chemical knowledge. The resulting complexity index Cm is derived from abstracting the information content of a molecule by the degrees of freedom in the microenvironments on a per-atom basis, allowing the molecular complexity to be calculated in a simple and additive way. This index allows the complexity of any molecule to be universally assessed and is sensitive to stereochemistry, heteroatoms, and symmetry. The performance of this complexity index is evaluated and compared against the current state of the art. Its additive character gives consistent values also for very large molecules and supports direct comparisons of chemical reactions. Finally, this approach may provide a useful tool for medicinal chemistry in drug design and lead selection, as demonstrated by correlating molecular complexities of antibiotics with compound-specific parameters.

Mentoring perception and academic performance: an Academic Health Science Centre survey.

PubMed

Athanasiou, Thanos; Patel, Vanash; Garas, George; Ashrafian, Hutan; Shetty, Kunal; Sevdalis, Nick; Panzarasa, Pietro; Darzi, Ara; Paroutis, Sotirios

2016-10-01

To determine the association between professors' self-perception of mentoring skills and their academic performance. Two hundred and fifteen professors from Imperial College London, the first Academic Health Science Centre (AHSC) in the UK, were surveyed. The instrument adopted was the Mentorship Skills Self-Assessment Survey. Statement scores were aggregated to provide a score for each shared core, mentor-specific and mentee-specific skill. Univariate and multivariate regression analyses were used to evaluate their relationship with quantitative measures of academic performance (publications, citations and h-index). There were 104 professors that responded (response rate 48%). There were no statistically significant negative correlations between any mentoring statement and any performance measure. In contrast, several mentoring survey items were positively correlated with academic performance. The total survey score for frequency of application of mentoring skills had a statistically significant positive association with number of publications (B=0.012, SE=0.004, p=0.006), as did the frequency of acquiring mentors with number of citations (B=1.572, SE=0.702, p=0.030). Building trust and managing risks had a statistically significant positive association with h-index (B=0.941, SE=0.460, p=0.047 and B=0.613, SE=0.287, p=0.038, respectively). This study supports the view that mentoring is associated with high academic performance. Importantly, it suggests that frequent use of mentoring skills and quality of mentoring have positive effects on academic performance. Formal mentoring programmes should be considered a fundamental part of all AHSCs' configuration. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Structure variation of the index of refraction of GaAs-AlAs superlattices and multiple quantum wells

NASA Technical Reports Server (NTRS)

Kahen, K. B.; Leburton, J. P.

1985-01-01

A detailed calculation of the index refraction of various GaAs-AlAs superlattices is presented for the first time. The calculation is performed by using a hybrid approach which combines the k-p method with the pseudopotential technique. Appropriate quantization conditions account for the influence of the superstructures on the electronic properties of the systems. The results of the model are in very good agreement with the experimental data. In comparison with the index of refraction of the corresponding AlGaAs alloy, characterized by the same average mole fraction of Al, the results indicate that the superlattice index of refraction values attain maxima at the various quantized transition energies. For certain structures the difference can be as large as 2 percent. These results suggest that the waveguiding and dispersion relation properties of optoelectronic devices can be tailored to design for specific optical application by an appropriate choice of the superlattice structure parameters.

Psychometric and screening properties of the WHO-5 well-being index in adult outpatients with Type 1 or Type 2 diabetes mellitus.

PubMed

Hajos, T R S; Pouwer, F; Skovlund, S E; Den Oudsten, B L; Geelhoed-Duijvestijn, P H L M; Tack, C J; Snoek, F J

2013-02-01

The 5-item World Health Organization well-being index is a commonly used measure of emotional well-being, but research on psychometric properties in outpatients with diabetes is scarce. We examined psychometric and screening properties for depression of this index in a large sample of Dutch outpatients with diabetes. Patients with Type 1 (n = 384) and Type 2 (n = 549) diabetes from three outpatient clinics completed the WHO-5 index, the nine-item Patient Health Questionnaire, the Problem Areas in Diabetes survey and the Short Form-12 health survey. Internal consistency of the WHO-5 index was determined by Cronbach's alpha. The factor structure was tested by confirmatory factor analysis. Concurrent validity was assessed by correlations with the Patient Health Questionnaire, Problem Areas in Diabetes and the Short Form-12 mental component scores. Sensitivity and specificity of the WHO-5 index as depression screener were tested against two existing Patient Health Questionnaire cut-off scores for depression using receiver operating characteristic curves. A one-factor structure of the WHO-5 index was verified by confirmatory factor analysis for patients with Type 1 and Type 2 diabetes. Moderate to strong correlations were observed between the WHO-5 index and the Patient Health Questionnaire scores, the Problem Areas in Diabetes scores and the Short Form-12 mental component scores (r = 0.55-0.69, P < 0.001). Receiver operating characteristic curves showed that a WHO-5 index cut-off of < 50 performed best as an indication for likely depression, with sensitivity compared with a Patient Health Questionnaire score ≥ 10 and ≥ 12 of 79% and 88%, respectively, and specificity of 88% and 76%, respectively. The WHO-5 index is a short, psychometrically sound measure of emotional well-being that appears suitable for use as screening test for likely depression in outpatients with Type 1 and Type 2 diabetes. © 2012 The Author. Diabetic Medicine © 2012 Diabetes UK.

The Performance of ML, GLS, and WLS Estimation in Structural Equation Modeling under Conditions of Misspecification and Nonnormality.

ERIC Educational Resources Information Center

Olsson, Ulf Henning; Foss, Tron; Troye, Sigurd V.; Howell, Roy D.

2000-01-01

Used simulation to demonstrate how the choice of estimation method affects indexes of fit and parameter bias for different sample sizes when nested models vary in terms of specification error and the data demonstrate different levels of kurtosis. Discusses results for maximum likelihood (ML), generalized least squares (GLS), and weighted least…

Publications of the Jet Propulsion Laboratory 1989

NASA Technical Reports Server (NTRS)

1990-01-01

This bibliography describes and indexes by primary author the externally distributed technical reporting, released during 1989, that resulted from scientific and engineering work performed, or managed, by JPL. Three classes of publications are included: JPL publications in which the information is complete for a specific accomplishment; articles from the quarterly Telecommunications and Data Acquisition (TDA) Progress Report; and articles published in the open literature.

The Optimization of In-Memory Space Partitioning Trees for Cache Utilization

NASA Astrophysics Data System (ADS)

Yeo, Myung Ho; Min, Young Soo; Bok, Kyoung Soo; Yoo, Jae Soo

In this paper, a novel cache conscious indexing technique based on space partitioning trees is proposed. Many researchers investigated efficient cache conscious indexing techniques which improve retrieval performance of in-memory database management system recently. However, most studies considered data partitioning and targeted fast information retrieval. Existing data partitioning-based index structures significantly degrade performance due to the redundant accesses of overlapped spaces. Specially, R-tree-based index structures suffer from the propagation of MBR (Minimum Bounding Rectangle) information by updating data frequently. In this paper, we propose an in-memory space partitioning index structure for optimal cache utilization. The proposed index structure is compared with the existing index structures in terms of update performance, insertion performance and cache-utilization rate in a variety of environments. The results demonstrate that the proposed index structure offers better performance than existing index structures.

Strategies to diagnose ovarian cancer: new evidence from phase 3 of the multicentre international IOTA study

PubMed Central

Testa, A; Kaijser, J; Wynants, L; Fischerova, D; Van Holsbeke, C; Franchi, D; Savelli, L; Epstein, E; Czekierdowski, A; Guerriero, S; Fruscio, R; Leone, F P G; Vergote, I; Bourne, T; Valentin, L; Van Calster, B; Timmerman, D

2014-01-01

Background: To compare different ultrasound-based international ovarian tumour analysis (IOTA) strategies and risk of malignancy index (RMI) for ovarian cancer diagnosis using a meta-analysis approach of centre-specific data from IOTA3. Methods: This prospective multicentre diagnostic accuracy study included 2403 patients with 1423 benign and 980 malignant adnexal masses from 2009 until 2012. All patients underwent standardised transvaginal ultrasonography. Test performance of RMI, subjective assessment (SA) of ultrasound findings, two IOTA risk models (LR1 and LR2), and strategies involving combinations of IOTA simple rules (SRs), simple descriptors (SDs) and LR2 with and without SA was estimated using a meta-analysis approach. Reference standard was histology after surgery. Results: The areas under the receiver operator characteristic curves of LR1, LR2, SA and RMI were 0.930 (0.917–0.942), 0.918 (0.905–0.930), 0.914 (0.886–0.936) and 0.875 (0.853–0.894). Diagnostic one-step and two-step strategies using LR1, LR2, SR and SD achieved summary estimates for sensitivity 90–96%, specificity 74–79% and diagnostic odds ratio (DOR) 32.8–50.5. Adding SA when IOTA methods yielded equivocal results improved performance (DOR 57.6–75.7). Risk of Malignancy Index had sensitivity 67%, specificity 91% and DOR 17.5. Conclusions: This study shows all IOTA strategies had excellent diagnostic performance in comparison with RMI. The IOTA strategy chosen may be determined by clinical preference. PMID:24937676

Predicting survival across chronic interstitial lung disease: the ILD-GAP model.

PubMed

Ryerson, Christopher J; Vittinghoff, Eric; Ley, Brett; Lee, Joyce S; Mooney, Joshua J; Jones, Kirk D; Elicker, Brett M; Wolters, Paul J; Koth, Laura L; King, Talmadge E; Collard, Harold R

2014-04-01

Risk prediction is challenging in chronic interstitial lung disease (ILD) because of heterogeneity in disease-specific and patient-specific variables. Our objective was to determine whether mortality is accurately predicted in patients with chronic ILD using the GAP model, a clinical prediction model based on sex, age, and lung physiology, that was previously validated in patients with idiopathic pulmonary fibrosis. Patients with idiopathic pulmonary fibrosis (n=307), chronic hypersensitivity pneumonitis (n=206), connective tissue disease-associated ILD (n=281), idiopathic nonspecific interstitial pneumonia (n=45), or unclassifiable ILD (n=173) were selected from an ongoing database (N=1,012). Performance of the previously validated GAP model was compared with novel prediction models in each ILD subtype and the combined cohort. Patients with follow-up pulmonary function data were used for longitudinal model validation. The GAP model had good performance in all ILD subtypes (c-index, 74.6 in the combined cohort), which was maintained at all stages of disease severity and during follow-up evaluation. The GAP model had similar performance compared with alternative prediction models. A modified ILD-GAP Index was developed for application across all ILD subtypes to provide disease-specific survival estimates using a single risk prediction model. This was done by adding a disease subtype variable that accounted for better adjusted survival in connective tissue disease-associated ILD, chronic hypersensitivity pneumonitis, and idiopathic nonspecific interstitial pneumonia. The GAP model accurately predicts risk of death in chronic ILD. The ILD-GAP model accurately predicts mortality in major chronic ILD subtypes and at all stages of disease.

MRI versus breast-specific gamma imaging (BSGI) in newly diagnosed ductal cell carcinoma-in-situ: a prospective head-to-head trial.

PubMed

Keto, Jessica L; Kirstein, Laurie; Sanchez, Diana P; Fulop, Tamara; McPartland, Laura; Cohen, Ilona; Boolbol, Susan K

2012-01-01

Mammography remains the standard imaging technique for the diagnosis of ductal carcinoma-in-situ (DCIS). Functional breast imaging, including breast magnetic resonance imaging (MRI), has known limitations in evaluating DCIS. To date, there are limited data on the utility of breast-specific gamma imaging (BSGI) in DCIS. We sought to prospectively compare the sensitivity of BSGI to MRI in newly diagnosed DCIS patients. Patients with newly diagnosed DCIS from June 1, 2009, through May 31, 2010, underwent a protocol with both breast MRI and BSGI. Each imaging study was read by a separate dedicated breast radiologist. Patients were excluded if excisional biopsy was performed for diagnosis, if their MRI was performed at an outside facility, or if final pathology revealed invasive carcinoma. There were 18 patients enrolled onto the study that had both MRI and BSGI for newly diagnosed DCIS. The sensitivity for MRI was 94% and for BSGI was 89% (P > 0.5, NS). There was one index tumor not seen on either MRI or BSGI, and one index tumor seen on MRI but not visualized on BSGI. Although BSGI has previously been shown to be as sensitive as MRI for detecting known invasive breast carcinoma, this study shows that BSGI is equally as sensitive as MRI at detecting newly diagnosed DCIS. As a result of the limited number of patients enrolled onto the study, larger prospective studies need to be performed to determine the true sensitivity and specificity of BSGI.

Minimum important differences for the patient-specific functional scale, 4 region-specific outcome measures, and the numeric pain rating scale.

PubMed

Abbott, J Haxby; Schmitt, John

2014-08-01

Multicenter, prospective, longitudinal cohort study. To investigate the minimum important difference (MID) of the Patient-Specific Functional Scale (PSFS), 4 region-specific outcome measures, and the numeric pain rating scale (NPRS) across 3 levels of patient-perceived global rating of change in a clinical setting. The MID varies depending on the external anchor defining patient-perceived "importance." The MID for the PSFS has not been established across all body regions. One thousand seven hundred eight consecutive patients with musculoskeletal disorders were recruited from 5 physical therapy clinics. The PSFS, NPRS, and 4 region-specific outcome measures-the Oswestry Disability Index, Neck Disability Index, Upper Extremity Functional Index, and Lower Extremity Functional Scale-were assessed at the initial and final physical therapy visits. Global rating of change was assessed at the final visit. MID was calculated for the PSFS and NPRS (overall and for each body region), and for each region-specific outcome measure, across 3 levels of change defined by the global rating of change (small, medium, large change) using receiver operating characteristic curve methodology. The MID for the PSFS (on a scale from 0 to 10) ranged from 1.3 (small change) to 2.3 (medium change) to 2.7 (large change), and was relatively stable across body regions. MIDs for the NPRS (-1.5 to -3.5), Oswestry Disability Index (-12), Neck Disability Index (-14), Upper Extremity Functional Index (6 to 11), and Lower Extremity Functional Scale (9 to 16) are also reported. We reported the MID for small, medium, and large patient-perceived change on the PSFS, NPRS, Oswestry Disability Index, Neck Disability Index, Upper Extremity Functional Index, and Lower Extremity Functional Scale for use in clinical practice and research.

[Development of a portable fall risk index for elderly people living in the community].

PubMed

Toba, Kenji; Okochi, Jiro; Takahashi, Tai; Matsubayashi, Kozo; Nishinaga, Masanori; Yamada, Shizuru; Takahashi, Ryutaro; Nishijima, Reiko; Kobayashi, Yoshio; Machida, Ayako; Akishita, Masahiro; Sasaki, Hidetada

2005-05-01

To develop a portable risk index for falls. Risk factors were chosen from previously established factors then we added several environmental factors to the risk index; previous falls in the last 12 month, trippig or stumbling, inability to ascend or descend stairs without help, decreased walking speed, inability to cross a road within the green signal interval, inability to walk 1km without a break, inability to stand on one leg for 5 seconds (eyes open), using a cane, inability to wring out a towel, dizziness or faintness, stooped or rounded back, knee joint pain, visual disturbance, hearing disturbance, cognitive decline, fear of falling, receiving 5 or more prescribed drugs, sensation of darkness at home, obstacles inside, barrier on the carpet or floor, using steps daily at home, steep slopes around home. The questionnaire sheet was completed by 2,439 community-dwelling elderly subjects (76.3 +/- 7.4 years old). The frequency of each items of fall risk index was compared between fallers (history of fall within one year) and non-fallers. Multiple regression analysis was performed to identify independent risk factors for previous falls. Except barrier, step use and steep slope around home, all items in the fall risk index were more frequent in fallers. Multivariate analysis revealed that tripping or stumbling, inability to cross a road within the green signal interval, dizziness or faintness, obstacles inside, inability to wring out a towel, cane use and knee joint pain were independent risk factors for previous falls. These 7 selected items were further analyzed as predictors. The maximum sum of sensitivity and specificity was reached at the cut-off point of 2/3 (sensitivity 0.65, specificity 0.72) by receiver operating curve. Portable fall risk index is useful for clinical settings to identify high-risk subjects.

Evaluation of the efficacy of nutritional screening tools to predict malnutrition in the elderly at a geriatric care hospital

PubMed Central

Baek, Myoung-Ha

2015-01-01

BACKGROUND/OBJECTIVES Malnutrition in the elderly is a serious problem, prevalent in both hospitals and care homes. Due to the absence of a gold standard for malnutrition, herein we evaluate the efficacy of five nutritional screening tools developed or used for the elderly. SUBJECTS/METHODS Elected medical records of 141 elderly patients (86 men and 55 women, aged 73.5 ± 5.2 years) hospitalized at a geriatric care hospital were analyzed. Nutritional screening was performed using the following tools: Mini Nutrition Assessment (MNA), Mini Nutrition Assessment-Short Form (MNA-SF), Geriatric Nutritional Risk Index (GNRI), Malnutrition Universal Screening Tool (MUST) and Nutritional Risk Screening 2002 (NRS 2002). A combined index for malnutrition was also calculated as a reference tool. Each patient evaluated as malnourished to any degree or at risk of malnutrition according to at least four out of five of the aforementioned tools was categorized as malnourished in the combined index classification. RESULTS According to the combined index, 44.0% of the patients were at risk of malnutrition to some degree. While the nutritional risk and/or malnutrition varied greatly depending on the tool applied, ranging from 36.2% (MUST) to 72.3% (MNA-SF). MUST showed good validity (sensitivity 80.6%, specificity 98.7%) and almost perfect agreement (k = 0.81) with the combined index. In contrast, MNA-SF showed poor validity (sensitivity 100%, specificity 49.4%) and only moderate agreement (k = 0.46) with the combined index. CONCLUSIONS MNA-SF was found to overestimate the nutritional risk in the elderly. MUST appeared to be the most valid and useful screening tool to predict malnutrition in the elderly at a geriatric care hospital. PMID:26634053

Evaluation of the efficacy of nutritional screening tools to predict malnutrition in the elderly at a geriatric care hospital.

PubMed

Baek, Myoung-Ha; Heo, Young-Ran

2015-12-01

Malnutrition in the elderly is a serious problem, prevalent in both hospitals and care homes. Due to the absence of a gold standard for malnutrition, herein we evaluate the efficacy of five nutritional screening tools developed or used for the elderly. Elected medical records of 141 elderly patients (86 men and 55 women, aged 73.5 ± 5.2 years) hospitalized at a geriatric care hospital were analyzed. Nutritional screening was performed using the following tools: Mini Nutrition Assessment (MNA), Mini Nutrition Assessment-Short Form (MNA-SF), Geriatric Nutritional Risk Index (GNRI), Malnutrition Universal Screening Tool (MUST) and Nutritional Risk Screening 2002 (NRS 2002). A combined index for malnutrition was also calculated as a reference tool. Each patient evaluated as malnourished to any degree or at risk of malnutrition according to at least four out of five of the aforementioned tools was categorized as malnourished in the combined index classification. According to the combined index, 44.0% of the patients were at risk of malnutrition to some degree. While the nutritional risk and/or malnutrition varied greatly depending on the tool applied, ranging from 36.2% (MUST) to 72.3% (MNA-SF). MUST showed good validity (sensitivity 80.6%, specificity 98.7%) and almost perfect agreement (k = 0.81) with the combined index. In contrast, MNA-SF showed poor validity (sensitivity 100%, specificity 49.4%) and only moderate agreement (k = 0.46) with the combined index. MNA-SF was found to overestimate the nutritional risk in the elderly. MUST appeared to be the most valid and useful screening tool to predict malnutrition in the elderly at a geriatric care hospital.

Academic productivity among fellowship associated adult total joint reconstruction surgeons.

PubMed

Khan, Adam Z; Kelley, Benjamin V; Patel, Ankur D; McAllister, David R; Leong, Natalie L

2017-12-01

The Hirsch index (h-index) is a measure that evaluates both research volume and quality-taking into consideration both publications and citations of a single author. No prior work has evaluated academic productivity and contributions to the literature of adult total joint replacement surgeons. This study uses h-index to benchmark the academic impact and identify characteristics associated with productivity of faculty members at joint replacement fellowships. Adult reconstruction fellowship programs were obtained via the American Association of Hip and Knee Surgeons website. Via the San Francisco match and program-specific websites, program characteristics (Accreditation Council for Graduate Medical Education approval, academic affiliation, region, number of fellows, fellow research requirement), associated faculty members, and faculty-specific characteristics (gender, academic title, formal fellowship training, years in practice) were obtained. H-index and total faculty publications served as primary outcome measures. Multivariable linear regression determined statistical significance. Sixty-six adult total joint reconstruction fellowship programs were identified: 30% were Accreditation Council for Graduate Medical Education approved and 73% had an academic affiliation. At these institutions, 375 adult reconstruction surgeons were identified; 98.1% were men and 85.3% had formal arthroplasty fellowship training. Average number of publications per faculty member was 50.1 (standard deviation 76.8; range 0-588); mean h-index was 12.8 (standard deviation 13.8; range 0-67). Number of fellows, faculty academic title, years in practice, and formal fellowship training had a significant ( P < .05) positive correlation with both h-index and total publications. The statistical overview presented in this work can help total joint surgeons quantitatively benchmark their academic performance against that of their peers.

An special epithelial staining agents: folic acid receptor-mediated diagnosis (FRD) effectively and conveniently screen patients with cervical cancer.

PubMed

Lu, Meng-Han; Hu, Ling-Yun; Du, Xin-Xin; Yang, Min; Zhang, Wei-Yi; Huang, Ke; Li, Li-An; Jiang, Shu-Fang; Li, Ya-Li

2015-01-01

High-quality screening with cytology has markedly reduced mortality from cervical cancer. However, it needs experienced pathologists to review and make the final decisions. We have developed folic acid receptor-mediated diagnosis (FRD) kits to effectively and conveniently screen patients with cervical cancer. We conduct present study aim to assess clinical significances of FRD in screening cervical cancer. A total of 169 patients were enrolled at Chinese People's liberation Army (PLA) general hospital. We compared diagnostic significances of FRD with thinprep cytology test (TCT). Meanwhile, colposcopy was also performed to confirm any lesion suspicious for cervical cancer. The sensitivity and specificity of FRD were 71.93% and 66.07% in diagnosis cervical cancer, respectively. Meanwhile, the positive predictive values (PPV), negative predictive values (NPV), Youden index were 51.90%, 82.22%, 0.38, respectively. On the other hand, the sensitivity and specificity of TCT in diagnosis cervical cancer were 73.68% and 61.61% respectively. PPV, NPV and Youden index for TCT were 49.41%, 82.14% and 0.35 respectively. Overall, FRD have high values of sensitivity, specificity and Youden index. However, this difference failed to statistical significance. FRD have comparable diagnostic significance with TCT. Therefore, FRD might serve as one effective method to screen cervical cancer. Especially for those patients living in remote regions of China, where cytology was unavailable.

An special epithelial staining agents: folic acid receptor-mediated diagnosis (FRD) effectively and conveniently screen patients with cervical cancer

PubMed Central

Lu, Meng-Han; Hu, Ling-Yun; Du, Xin-Xin; Yang, Min; Zhang, Wei-Yi; Huang, Ke; Li, Li-An; Jiang, Shu-Fang; Li, Ya-Li

2015-01-01

High-quality screening with cytology has markedly reduced mortality from cervical cancer. However, it needs experienced pathologists to review and make the final decisions. We have developed folic acid receptor-mediated diagnosis (FRD) kits to effectively and conveniently screen patients with cervical cancer. We conduct present study aim to assess clinical significances of FRD in screening cervical cancer. A total of 169 patients were enrolled at Chinese People’s liberation Army (PLA) general hospital. We compared diagnostic significances of FRD with thinprep cytology test (TCT). Meanwhile, colposcopy was also performed to confirm any lesion suspicious for cervical cancer. The sensitivity and specificity of FRD were 71.93% and 66.07% in diagnosis cervical cancer, respectively. Meanwhile, the positive predictive values (PPV), negative predictive values (NPV), Youden index were 51.90%, 82.22%, 0.38, respectively. On the other hand, the sensitivity and specificity of TCT in diagnosis cervical cancer were 73.68% and 61.61% respectively. PPV, NPV and Youden index for TCT were 49.41%, 82.14% and 0.35 respectively. Overall, FRD have high values of sensitivity, specificity and Youden index. However, this difference failed to statistical significance. FRD have comparable diagnostic significance with TCT. Therefore, FRD might serve as one effective method to screen cervical cancer. Especially for those patients living in remote regions of China, where cytology was unavailable. PMID:26221336

Risk factors and decision criteria for intensive chemotherapy in older patients with acute myeloid leukemia.

PubMed

Malfuson, Jean-Valère; Etienne, Anne; Turlure, Pascal; de Revel, Thierry; Thomas, Xavier; Contentin, Nathalie; Terré, Christine; Rigaudeau, Sophie; Bordessoule, Dominique; Vey, Norbert; Gardin, Claude; Dombret, Hervé

2008-12-01

There is a need for standardization of treatment decisions in older patients with acute myeloid leukemia. The aim of the present study was to analyze the decisional value of poor risk factors in 416 elderly patients treated in the ALFA-9803 trial in order to derive a decisional index. Standard multivariate analysis was used to identify risk factors for overall survival. Risk factors were then considered as good decision tools if associated with a frequency >10% and a false positive rate <10% in predicting overall survival as poor as observed after low-dose cytarabine therapy (25% survival or less at 12 months). Among six independent risk factors (age, performance status, white blood cell count, hematopoietic cell transplantation comorbidity index, infection at baseline, and cytogenetics), cytogenetics was the only potent, independent decision tool. High hematopoietic cell transplantation comorbidity index scores or infections were found too rarely to guide further decisions. The three other factors (age, performance status, and white cell count) needed to be combined to provide a good specificity. The proposed decisional index, therefore, included high-risk cytogenetics and/or the presence of at least two of the following criteria: age > or =75 years, performance status > or =2, and white cell count > or =50 x 10(9)/L. This simple two-class decisional index, which was validated in an independent patient set, enabled us to discriminate 100 patients (24%) who had an estimated overall survival of only 19% at 12 months, with a good 9% false positive rate. We propose waiting for cytogenetic information before making treatment decisions in elderly patients with acute myeloid leukemia. Those patients with unfavorable cytogenetics, as well as patients with at least two of the following features, age > or =75 years, performance status > or =2, and white cell count > or =50 x 10(9)/L, should not be considered for standard intensive chemotherapy (ClinicalTrials.gov identifier: NCT00363025).

Measuring the impact of dermatological conditions on family and caregivers: a review of dermatology-specific instruments.

PubMed

Sampogna, F; Finlay, A Y; Salek, S S; Chernyshov, P; Dalgard, F J; Evers, A W M; Linder, D; Manolache, L; Marron, S E; Poot, F; Spillekom-van Koulil, S; Svensson, Å; Szepietowski, J C; Tomas-Aragones, L; Abeni, D

2017-09-01

The patient is the centre of a web of relationships, and the impact of his/her disease on family members and caregivers must be taken into account. The aim of this study was to identify the specific instruments that measure the impact of a dermatological disease on the quality of life (QoL) of family members, by performing a systematic search of the literature. Fifteen papers were identified, describing the creation and validation of nine instruments. Four of them concerned atopic dermatitis (Dermatitis Family Index, DFI; Parents' Index QoL Atopic Dermatitis, PiQoL-AD; QoL in primary caregivers of children with atopic dermatitis, QPCAD; Childhood Atopic Dermatitis Impact Scale, CADIS), two measured the impact of psoriasis in family members (Psoriasis Family Index, PFI; FamilyPso), one the impact of epidermolysis bullosa (Epidermolysis Bullosa Burden of Disease, EB-BoD), one of ichthyosis (Family Burden Ichthyosis, FBI), and one was generic for dermatological conditions (Family Dermatology Life Quality Index, FDLQI). The European Academy of Dermatology and Venereology quality of life taskforce recommends that the impact of a skin disease on family and caregivers should be measured as part of any thorough evaluation of the burden of a disease. Guidelines are given to choose the most appropriate instruments. © 2017 European Academy of Dermatology and Venereology.

Effect of severe kwashiorkor on intellectual development among Nigerian children.

PubMed

Nwuga, V C

1977-09-01

A study was conducted to investigated the intellectual sequelae of severe kwashiorkor among Nigerian children of school age. The design for the study had an experimental urban kwashiorkor (index) group and four control groups, namely, a sibling group, a lower class group, an upper class group, and a rural kwashiorkor group. Various psychological tests measuring specific intellectual abilities were administered to all of the subjects taking part in the study. The findings showed that the index group had lower levels of certain types of intellectual skill-specifically the higher cognitive skills-at school age than their siblings, and more so than other controls except their rural counterparts; males showed a tendency to be more affected by severe kwashiorkor with regard to mental development than their female counterparts; there was no relationship between scores in the psychological tests and the ages at which the index cases were admitted into hospital; the upper class was clearly superior in performance of the tests and also in measures of weight and head measurements when compared to all of the other groups; there was no relationship between head circumference and scores in the tests among subjects in the five groups.

Construction and validation of the chronic acquired polyneuropathy patient-reported index, “CAP-PRI:” a disease-specific, health-related quality of life instrument

PubMed Central

Gwathmey, Kelly G.; Conaway, Mark R.; Seyedsadjadi, Reza; Joshi, Amruta; Barnett, Carolina; Bril, Vera; Ng, Eduardo; David, William; Gable, Karissa; Guptill, Jeffrey T.; Hobson-Webb, Lisa D.; Dineen, Jennifer; Hehir, Michael; Brannagan, Thomas H.; Byun, Esther; Adler, Margaret; Burns, Ted M.

2016-01-01

Introduction Generic health-related quality of life (HRQOL) patient-reported outcome measures have been used in patients with chronic immune-mediated polyneuropathies. We have created a disease-specific HRQOL instrument. Methods and Results The 15-item chronic acquired polyneuropathy patient-reported index (CAP-PRI) was developed and validated in multiple steps. Items were initially generated through patient and specialist input. The performance of the preliminary 20 items was analyzed from a prospective, 5-center study involving chronic immune-mediated polyneuropathy patients. Data analysis suggested modification to a 15-item scale with 3 response categories, rather than 5. The final CAP-PRI was then validated in another prospective, 5-center study. The CAP-PRI appeared to be a unidimensional outcome measure that fits the Rasch Partial Credit Model in our multicenter cohort. It correlated appropriately with the outcome measures commonly used in this patient population. Discussion The CAP-PRI is a simple, easy, disease-specific HRQOL measure that appears to be useful for clinical care and possibly also for clinical trials. PMID:26600438

Modulated cortical control of individual fingers in experienced musicians: an EEG study. Electroencephalographic study.

PubMed

Slobounov, S; Chiang, H; Johnston, J; Ray, W

2002-12-01

The present research was designed to address the nature of interdependency between fingers during force production tasks in subjects with varying experience in performing independent finger manipulation. Specifically, behavioral and electroencephalographic (EEG) measures associated with controllability of the most enslaved (ring) and the least enslaved (index) fingers was examined in musicians and non-musicians. Six piano players and 6 age-matched control subjects performed a series of isometric force production tasks with the index and ring fingers. Subjects produced 3 different force levels with either their index or ring fingers. We measured the isometric force output produced by all 4 fingers (index, ring, middle and little), including both ramp and static phases of force production. We applied time-domain averaging of EEG single trials in order to extract 4 components of the movement-related cortical potentials (MRCP) preceding and accompanying force responses. Three behavioral findings were observed. First, musicians were more accurate than non-musicians at reaching the desired force level. Second, musicians showed less enslaving as compared to non-musicians. And third, the amount of enslaving increased with the increment of nominal force levels regardless of whether the index or ring finger was used as the master finger. In terms of EEG measures, we found differences between tasks performed with the index and ring fingers in non-musicians. For musicians, we found larger MRCP amplitudes at most electrode sites for the ring finger. Our data extends previous enslaving research and suggest an important role for previous experience in terms of the independent use of the fingers. Given that a variety of previous work has shown finger independence to be reflected in cortical representation in the brain and our findings of MRCP amplitude associated with greater independence of fingers in musicians, this suggests that what has been considered to be stable constraints in terms of finger movements can be modulated by experience. This work supports the idea that experience is associated with changes in behavioral and EEG correlates of task performance and may have clinical implications in disorders such as stroke or focal hand dystonia. Practice-related procedures offer useful approaches to rehabilitation strategies.

Qualitation and quantification of specific polysaccharides from Panax species using GC-MS, saccharide mapping and HPSEC-RID-MALLS.

PubMed

Cheong, Kit-Leong; Wu, Ding-Tao; Deng, Yong; Leong, Fong; Zhao, Jing; Zhang, Wen-Jie; Li, Shao-Ping

2016-11-20

The objective of this study was to qualify and quantify the specific polysaccharides in Panax spp. The analyses of specific polysaccharides were performed by using GC-MS, saccharide mapping and high performance size exclusion chromatography (HPSEC) coupled with multi angle laser light scattering (MALLS) and refractive index detector (RID). Results showed that compositional monosaccharides were the same in different species of Panax and composed of rhamnose, arabinose, galacturonic acid, mannose, glucose, and galactose. Saccharide mapping results showed that glycosides linkages, which existed in specific polysaccharides from Panax spp., were similar. Additionally, the content of specific polysaccharides of P. ginseng, P. notoginseng and P. quinquefolium were 17.9-20.5mg/g, 11.9-15.0mg/g, and 9.9-13.3mg/g, respectively. P. ginseng, P. notoginseng, and P. quinquefolium could be clustered into three groups using both hierarchical cluster analysis and principal component analysis. The results possessed great potential in characterization and content determination of specific polysaccharides in Panax spp. Copyright © 2016 Elsevier Ltd. All rights reserved.

Left ventricular longitudinal strain in soccer referees.

PubMed

Gianturco, Luigi; Bodini, Bruno; Gianturco, Vincenzo; Lippo, Giuseppina; Solbiati, Agnese; Turiel, Maurizio

2017-06-13

Along the years, the analysis of soccer referees perfomance has interested the experts and we can find several types of studies in literature using in particular cardiac imaging. The aim of this retrospective study was to observe relationship between VO2max uptake and some conventional and not-conventional echocardiographic parameters. In order to perform this evaluation, we have enrolled 20 referees, belonging to Italian Soccer Referees' Association and we have investigated cardiovascular profile of them. We found a strong direct relationship between VO2max and global longitudinal strain of left ventricle assessed by means of speckle tracking echocardiographic analysis (R2=0.8464). The most common classic echocardiographic indexes have showed mild relations (respectively, VO2max vs EF: R2=0.4444; VO2max vs LV indexed mass: R2=0.2268). Therefore, our study suggests that longitudinal strain could be proposed as a specific echocardiographic parameter to evaluate the soccer referees performance.

Embedded performance validity tests within the Hopkins Verbal Learning Test - Revised and the Brief Visuospatial Memory Test - Revised.

PubMed

Sawyer, R John; Testa, S Marc; Dux, Moira

2017-01-01

Various research studies and neuropsychology practice organizations have reiterated the importance of developing embedded performance validity tests (PVTs) to detect potentially invalid neurocognitive test data. This study investigated whether measures within the Hopkins Verbal Learning Test - Revised (HVLT-R) and the Brief Visuospatial Memory Test - Revised (BVMT-R) could accurately classify individuals who fail two or more PVTs during routine clinical assessment. The present sample of 109 United States military veterans (Mean age = 52.4, SD = 13.3), all consisted of clinically referred patients and received a battery of neuropsychological tests. Based on performance validity findings, veterans were assigned to valid (n = 86) or invalid (n = 23) groups. Of the 109 patients in the overall sample, 77 were administered the HLVT-R and 75 were administered the BVMT-R, which were examined for classification accuracy. The HVLT-R Recognition Discrimination Index and the BVMT-R Retention Percentage showed good to adequate discrimination with an area under the curve of .78 and .70, respectively. The HVLT-R Recognition Discrimination Index showed sensitivity of .53 with specificity of .93. The BVMT-R Retention Percentage demonstrated sensitivity of .31 with specificity of .92. When used in conjunction with other PVTs, these new embedded PVTs may be effective in the detection of invalid test data, although they are not intended for use in patients with dementia.

Use of Dietary Indexes among Children in Developed Countries12

PubMed Central

Lazarou, Chrystalleni; Newby, P. K.

2011-01-01

In this article, we review studies that have used dietary indexes to assess different aspects of diet in relation to health outcomes and sociodemographic factors in childhood populations of developed countries. Eighty-four papers published from 1980 to mid-2010 including 90 unique dietary indexes were reviewed. Seventy-two indexes were developed (or have been adapted) specifically for childhood populations; 38 of these were used to assess diet-disease associations, mostly of diet and obesity. In the majority of these studies, small inverse associations between dietary indexes and obesity indexes were shown. Children who were younger, female, and from high-income families had better dietary quality scores. Forty-nine indexes (of 90) were compared with other aspects of dietary intakes or behaviors, with correlations ranging from very low to modest (∼r = 0.05–0.50). Only 2 validation studies compared an index with nutritional biomarkers, and correlations were quite weak for most plasma nutrients (P < 0.10). Overall, a large number of indexes have been created and used, but the majority of studies are descriptive. Fewer analytic studies on index-health associations have been performed, and most analyses insufficiently adjusted for confounders. Thus, prospective and intervention research in diverse populations is needed to further test these tools. In conclusion, indexes are potentially useful methods for dietary assessment, because they offer valuable information on overall dietary patterns in children. However, understanding the advantages and limitations when applying them in research and public health settings is important, and more research is needed to further develop their utility. PMID:22332071

May a unitary autonomic index help assess autonomic cardiac regulation in elite athletes? Preliminary observations on the national Italian Olympic committee team.

PubMed

Sala, Roberto; Malacarne, Mara; Tosi, Fabio; Benzi, Manuela; Solaro, Nadia; Tamorri, Stefano; Spataro, Antonio; Pagani, Massimo; Lucini, Daniela

2017-12-01

Long term endurance training, as occurring in elite athletes, is associated to cardiac neural remodeling in favor of cardioprotective vagal mechanisms, resulting in resting bradycardia and augmented contribution of cardiac parasympathetic nerve activity. Autonomic assessment can be performed by way of heart rate variability. This technique however provides multiple indices, and there is not yet complete agreement on their specific significance. Purpose of the study was to assess whether a rank transformation and radar plot could provide a unitary autonomic index, capable to show a correlation between intensity of individual work and quality of autonomic regulation. We studied 711 (23.6±6.2 years) elite athletes that took part in the selection procedure for the 2016 Rio Olympic Games for the National Italian Olympic Committee (CONI). Indices from Heart Rate Variability HRV obtained at rest, during standing up and during recovery from an exercise test were used to compute a percent ranked unitary autonomic index for sport (ANSIs), taken as proxy of quality of autonomic regulation. Within the observed wide range of energy expenditure, the unitary autonomic index ANSIs appears significantly correlated to individual and discipline specific training workloads (r=0.25, P<0.001 and r=0.78, P<0.001, respectively), correcting for possible age and gender bias. ANSIs also positively correlates to lipid profile. Estimated intensity of physical activity correlates with quality of cardiac autonomic regulation, as expressed by a novel unitary index of cardiac autonomic regulation. ANSIs could provide a novel and convenient approach to individual autonomic evaluation in athletes.

Ankle-Brachial index by oscillometry: A very useful method to assess peripheral arterial disease in diabetes

PubMed Central

Premanath, M.; Raghunath, M.

2010-01-01

Background: Peripheral Arterial Disease (PAD) remains the least recognized form of atherosclerosis. The Ankle-Brachial Index (ABI) has emerged as one of the potent markers of diffuse atherosclerosis, cardiovascular (CV) risk, and overall survival in general public, especially in diabetics. The important reason for the lack of early diagnosis is the non-availability of a test that is easy to perform and less expensive, with no training required. Objectives: To evaluate the osillometric method of performing ABI with regard to its usefulness in detecting PAD cases and to correlate the signs and symptoms with ABI. Materials and Methods: Two hundred diabetics of varying duration attending the clinic for a period of eight months, from August 2006 to April 2007, were evaluated for signs, symptoms, and risk factors. ABI was performed using the oscillometric method. The positives were confirmed by Doppler evaluation. An equal number of age- and sex-matched controls, which were ABI negative, were also assessed by Doppler. Sensitivity and Specificity were determined. Results: There were 120 males and 80 females. Twelve males (10%) and six females (7.5%) were ABI positive. On Doppler, eleven males (91.5%) and three females (50%) were true positives. There were six false negatives from the controls (three each). The Sensitivity was 70% and Specificity was 75%. Symptoms and signs correlated well with ABI positives. Hypertension was the most important risk factor. Conclusions: In spite of the limitations, the oscillometric method of performing ABI is a simple procedure, easy to perform, does not require training and can be performed as an outpatient procedure not only by doctors, but also by the paramedical staff to detect more PAD cases. PMID:20535314

Reciprocating and Screw Compressor semi-empirical models for establishing minimum energy performance standards

NASA Astrophysics Data System (ADS)

Javed, Hassan; Armstrong, Peter

2015-08-01

The efficiency bar for a Minimum Equipment Performance Standard (MEPS) generally aims to minimize energy consumption and life cycle cost of a given chiller type and size category serving a typical load profile. Compressor type has a significant chiller performance impact. Performance of screw and reciprocating compressors is expressed in terms of pressure ratio and speed for a given refrigerant and suction density. Isentropic efficiency for a screw compressor is strongly affected by under- and over-compression (UOC) processes. The theoretical simple physical UOC model involves a compressor-specific (but sometimes unknown) volume index parameter and the real gas properties of the refrigerant used. Isentropic efficiency is estimated by the UOC model and a bi-cubic, used to account for flow, friction and electrical losses. The unknown volume index, a smoothing parameter (to flatten the UOC model peak) and bi-cubic coefficients are identified by curve fitting to minimize an appropriate residual norm. Chiller performance maps are produced for each compressor type by selecting optimized sub-cooling and condenser fan speed options in a generic component-based chiller model. SEER is the sum of hourly load (from a typical building in the climate of interest) and specific power for the same hourly conditions. An empirical UAE cooling load model, scalable to any equipment capacity, is used to establish proposed UAE MEPS. Annual electricity use and cost, determined from SEER and annual cooling load, and chiller component cost data are used to find optimal chiller designs and perform life-cycle cost comparison between screw and reciprocating compressor-based chillers. This process may be applied to any climate/load model in order to establish optimized MEPS for any country and/or region.

Index to Estimate the Efficiency of an Ophthalmic Practice.

PubMed

Chen, Andrew; Kim, Eun Ah; Aigner, Dennis J; Afifi, Abdelmonem; Caprioli, Joseph

2015-08-01

A metric of efficiency, a function of the ratio of quality to cost per patient, will allow the health care system to better measure the impact of specific reforms and compare the effectiveness of each. To develop and evaluate an efficiency index that estimates the performance of an ophthalmologist's practice as a function of cost, number of patients receiving care, and quality of care. Retrospective review of 36 ophthalmology subspecialty practices from October 2011 to September 2012 at a university-based eye institute. The efficiency index (E) was defined as a function of adjusted number of patients (N(a)), total practice adjusted costs (C(a)), and a preliminary measure of quality (Q). Constant b limits E between 0 and 1. Constant y modifies the influence of Q on E. Relative value units and geographic cost indices determined by the Centers for Medicare and Medicaid for 2012 were used to calculate adjusted costs. The efficiency index is expressed as the following: E = b(N(a)/C(a))Q(y). Independent, masked auditors reviewed 20 random patient medical records for each practice and filled out 3 questionnaires to obtain a process-based quality measure. The adjusted number of patients, adjusted costs, quality, and efficiency index were calculated for 36 ophthalmology subspecialties. The median adjusted number of patients was 5516 (interquartile range, 3450-11,863), the median adjusted cost was 1.34 (interquartile range, 0.99-1.96), the median quality was 0.89 (interquartile range, 0.79-0.91), and the median value of the efficiency index was 0.26 (interquartile range, 0.08-0.42). The described efficiency index is a metric that provides a broad overview of performance for a variety of ophthalmology specialties as estimated by resources used and a preliminary measure of quality of care provided. The results of the efficiency index could be used in future investigations to determine its sensitivity to detect the impact of interventions on a practice such as training modules or practice restructuring.

Proposal of a production and management index (PMI) for tilapia farms.

PubMed

Muniesa, A; Rey-Castaño, A L; Ruiz-Zarzuela, I; Guarín, M; Iregui, C; de Blas, I

2016-11-01

Tilapia is one of the most important species in aquaculture; however, there is no available index to show the performance of a production unit. It is desirable to assess the productivity using indexes, such as the production and management index for shrimps and the European production efficacy factor for broilers. These indexes are based on data production: growth, survival, and feed conversion of a full production cycle. Taking into account these parameters, we propose a production and management index (PMI) for tilapia that is applicable for a specific period of the production cycle. For the construction and validation of the PMI we have used production data from 8,614 monthly records of 2 tilapia farms in Huila Department (Colombia), and because of the complexity of tilapia management, different anomalous situations have been detected and then defined as exceptions. As a result, 419 records were considered extreme values because 1 or more exceptions were met. The value of the PMI varies from 0 (the worst situation) to 3.55, which reflects high variability. We have constructed a PMI for tilapia as the product of 3 elements to obtain a positive value index. Instead of classic parameters, we had to calculate an adapted version of them: the relative average daily growth, the survival (as a complementary value of the estimated monthly mortality), and a feed conversion ratio index. To assess the utility of the PMI, some comparisons were performed using records from black and red tilapia. We observed significant differences depending on tilapia strain (PMI = 1.0248 vs. PMI = 1.1661; < 0.001), age (better values for small fish), and season (PMI = 1.0847 vs. PMI = 1.1011; = 0.026). According to these results, we can conclude that the PMI could be a useful tool for tilapia farmers, despite the complexity of the calculation.

An information sources map for Occupational and Environmental Medicine: guidance to network-based information through domain-specific indexing.

PubMed Central

Silverstein, S. M.; Miller, P. L.; Cullen, M. R.

1993-01-01

This paper describes a prototype information sources map (ISM), an on-line information source finder, for Occupational and Environmental Medicine (OEM). The OEM ISM was built as part of the Unified Medical Language System (UMLS) project of the National Library of Medicine. It allows a user to identify sources of on-line information appropriate to a specific OEM question, and connect to the sources. In the OEM ISM we explore a domain-specific method of indexing information source contents, and also a domain-specific user interface. The indexing represents a domain expert's opinion of the specificity of an information source in helping to answer specific types of domain questions. For each information source, an index field represents whether a source might provide useful information in an occupational, industrial, or environmental category. Additional fields represent the degree of specificity of a source in individual question types in each category. The paper discusses the development, design, and implementation of the prototype OEM ISM. PMID:8130548

Multi-Resolution Indexing for Hierarchical Out-of-Core Traversal of Rectilinear Grids

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pascucci, V.

2000-07-10

The real time processing of very large volumetric meshes introduces specific algorithmic challenges due to the impossibility of fitting the input data in the main memory of a computer. The basic assumption (RAM computational model) of uniform-constant-time access to each memory location is not valid because part of the data is stored out-of-core or in external memory. The performance of most algorithms does not scale well in the transition from the in-core to the out-of-core processing conditions. The performance degradation is due to the high frequency of I/O operations that may start dominating the overall running time. Out-of-core computing [28]more » addresses specifically the issues of algorithm redesign and data layout restructuring to enable data access patterns with minimal performance degradation in out-of-core processing. Results in this area are also valuable in parallel and distributed computing where one has to deal with the similar issue of balancing processing time with data migration time. The solution of the out-of-core processing problem is typically divided into two parts: (i) analysis of a specific algorithm to understand its data access patterns and, when possible, redesign the algorithm to maximize their locality; and (ii) storage of the data in secondary memory with a layout consistent with the access patterns of the algorithm to amortize the cost of each I/O operation over several memory access operations. In the case of a hierarchical visualization algorithms for volumetric data the 3D input hierarchy is traversed to build derived geometric models with adaptive levels of detail. The shape of the output models is then modified dynamically with incremental updates of their level of detail. The parameters that govern this continuous modification of the output geometry are dependent on the runtime user interaction making it impossible to determine a priori what levels of detail are going to be constructed. For example they can be dependent from external parameters like the viewpoint of the current display window or from internal parameters like the isovalue of an isocontour or the position of an orthogonal slice. The structure of the access pattern can be summarized into two main points: (i) the input hierarchy is traversed level by level so that the data in the same level of resolution or in adjacent levels is traversed at the same time and (ii) within each level of resolution the data is mostly traversed at the same time in regions that are geometrically close. In this paper I introduce a new static indexing scheme that induces a data layout satisfying both requirements (i) and (ii) for the hierarchical traversal of n-dimensional regular grids. In one particular implementation the scheme exploits in a new way the recursive construction of the Z-order space filling curve. The standard indexing that maps the input nD data onto a 1D sequence for the Z-order curve is based on a simple bit interleaving operation that merges the n input indices into one index n times longer. This helps in grouping the data for geometric proximity but only for a specific level of detail. In this paper I show how this indexing can be transformed into an alternative index that allows to group the data per level of resolution first and then the data within each level per geometric proximity. This yields a data layout that is appropriate for hierarchical out-of-core processing of large grids.« less

Development of an operational specific CAT risk (SCATR) index

NASA Technical Reports Server (NTRS)

Keller, J. L.; Haines, P. A.; Luers, J. K.

1983-01-01

The original formulations of Roach (1970) and Oard (1974) for the calculation of clear air turbulence (CAT) potential from synoptic scale data were extended. An index which gives a measure of the specific risk of encountering CAT - the specific clear air turbulence risk (SCATR) index - was defined. This index takes into account both the locally and advected contributions to the energy necessary for CAT. The advected contribution is associated with the role of atmospheric gravity waves. The SCATR index was calculated for a number of cases where documented encounters with CAT occurred. Of particular interest were those made for cases involving severe CAT. The results for the two severe CAT cases run were quite impressive and elicited considerable interest from operational aviation meteorologists.

Validation of the UNC OCT Index for the Diagnosis of Early Glaucoma

PubMed Central

Lee, Gary; Budenz, Donald L.; Warren, Joshua L.; Wall, Michael; Artes, Paul H.; Callan, Thomas M.; Flanagan, John G.

2018-01-01

Purpose To independently validate the performance of the University of North Carolina Optical Coherence Tomography (UNC OCT) Index in diagnosing and predicting early glaucoma. Methods Data of 118 normal subjects (118 eyes) and 96 subjects (96 eyes) with early glaucoma defined as visual field mean deviation (MD) greater than −4 decibels (dB), aged 40 to 80 years, and who were enrolled in the Full-Threshold Testing Size III, V, VI comparison study were used in this study. CIRRUS OCT average and quadrants' retinal nerve fiber layer (RNFL); optic disc vertical cup-to-disc ratio (VCDR), cup-to-disc area ratio, and rim area; and average, minimum, and six sectoral ganglion cell-inner plexiform layer (GCIPL) measurements were run through the UNC OCT Index algorithm. Area under the receiver operating characteristic curve (AUC) and sensitivities at 95% and 99% specificity were calculated and compared between single parameters and the UNC OCT Index. Results Mean age was 60.1 ± 11.0 years for normal subjects and 66.5 ± 8.1 years for glaucoma patients (P < 0.001). MD was 0.29 ± 1.04 dB and −1.30 ± 1.35 dB in normal and glaucomatous eyes (P < 0.001), respectively. The AUC of the UNC OCT Index was 0.96. The best single metrics when compared to the UNC OCT Index were VCDR (0.93, P = 0.054), average RNFL (0.92, P = 0.014), and minimum GCIPL (0.91, P = 0.009). The sensitivities at 95% and 99% specificity were 85.4% and 76.0% (UNC OCT Index), 71.9% and 62.5% (VCDR, all P < 0.001), 64.6% and 53.1% (average RNFL, all P < 0.001), and 66.7% and 58.3% (minimum GCIPL, all P < 0.001), respectively. Conclusions The findings confirm that the UNC OCT Index may provide improved diagnostic perforce over that of single OCT parameters and may be a good tool for detection of early glaucoma. Translational Relevance The UNC OCT Index algorithm may be incorporated easily into routine clinical practice and be useful for detecting early glaucoma. PMID:29629238

Validation of the UNC OCT Index for the Diagnosis of Early Glaucoma.

PubMed

Mwanza, Jean-Claude; Lee, Gary; Budenz, Donald L; Warren, Joshua L; Wall, Michael; Artes, Paul H; Callan, Thomas M; Flanagan, John G

2018-04-01

To independently validate the performance of the University of North Carolina Optical Coherence Tomography (UNC OCT) Index in diagnosing and predicting early glaucoma. Data of 118 normal subjects (118 eyes) and 96 subjects (96 eyes) with early glaucoma defined as visual field mean deviation (MD) greater than -4 decibels (dB), aged 40 to 80 years, and who were enrolled in the Full-Threshold Testing Size III, V, VI comparison study were used in this study. CIRRUS OCT average and quadrants' retinal nerve fiber layer (RNFL); optic disc vertical cup-to-disc ratio (VCDR), cup-to-disc area ratio, and rim area; and average, minimum, and six sectoral ganglion cell-inner plexiform layer (GCIPL) measurements were run through the UNC OCT Index algorithm. Area under the receiver operating characteristic curve (AUC) and sensitivities at 95% and 99% specificity were calculated and compared between single parameters and the UNC OCT Index. Mean age was 60.1 ± 11.0 years for normal subjects and 66.5 ± 8.1 years for glaucoma patients ( P < 0.001). MD was 0.29 ± 1.04 dB and -1.30 ± 1.35 dB in normal and glaucomatous eyes ( P < 0.001), respectively. The AUC of the UNC OCT Index was 0.96. The best single metrics when compared to the UNC OCT Index were VCDR (0.93, P = 0.054), average RNFL (0.92, P = 0.014), and minimum GCIPL (0.91, P = 0.009). The sensitivities at 95% and 99% specificity were 85.4% and 76.0% (UNC OCT Index), 71.9% and 62.5% (VCDR, all P < 0.001), 64.6% and 53.1% (average RNFL, all P < 0.001), and 66.7% and 58.3% (minimum GCIPL, all P < 0.001), respectively. The findings confirm that the UNC OCT Index may provide improved diagnostic perforce over that of single OCT parameters and may be a good tool for detection of early glaucoma. The UNC OCT Index algorithm may be incorporated easily into routine clinical practice and be useful for detecting early glaucoma.

Multiple Nonspecific Sites of Joint Pain Outside the Knees Develop in Persons With Knee Pain.

PubMed

Felson, David T; Niu, Jingbo; Quinn, Emily K; Neogi, Tuhina; Lewis, Cara L; Lewis, Cora E; Frey Law, Laura; McCulloch, Chuck; Nevitt, Michael; LaValley, Michael

2017-02-01

Many persons with knee pain have joint pain outside the knee, but despite the impact and high frequency of this pain, its distribution and causes have not been studied. We undertook this study to test the hypothesis of those studying gait abnormalities who have suggested that knee pain causes pain in adjacent joints but that pain adaptation strategies are highly individualized. We studied persons ages 50-79 years with or at high risk of knee osteoarthritis who were recruited from 2 community-based cohorts, the Multicenter Osteoarthritis Study and the Osteoarthritis Initiative, and we followed them up for 5-7 years. We excluded those with knee pain at baseline and compared those who had developed knee pain at the first follow-up examination (the index visit) with those who had not. We examined pain on most days at joint regions outside the knee in examinations after the index visit. Logistic regression analyses examined the risk of joint-specific pain adjusted for age, sex, body mass index, and symptoms of depression, and we performed sensitivity analyses excluding those with widespread pain. In the combined cohorts, 693 persons had knee pain at the index visit and 2,793 did not. A total of 79.6% of those with bilateral knee pain and 63.8% of those with unilateral knee pain had pain during follow-up in a joint region outside the knee, compared with 49.9% of those without knee pain. There was an increased risk of pain at most extremity joint sites, without a predilection for specific sites. Results were unchanged when those with widespread pain were excluded. Persons with chronic knee pain are at increased risk of pain in multiple joints in no specific pattern. © 2016, American College of Rheumatology.

Dimensions of the epilepsy foundation concerns index.

PubMed

Loring, David W; Larrabee, Glenn J; Meador, Kimford J; Lee, Gregory P

2005-05-01

We performed principal component analysis (PCA) of the Epilepsy Foundation Concerns Index scale in 189 patients undergoing evaluation for epilepsy surgery. We identified a five-factor solution in which there were no varimax-rotated factors consisting of fewer than two questions. Factor 1 reflects affective impact on enjoyment of life, Factor 2 reflects general autonomy concerns, Factor 3 reflects fear of seizure recurrence, Factor 4 reflects concern of being a burden to one's family, and Factor 5 reflects a perceived lack of understanding by others. Multiple regression using the Quality of Life in Epilepsy--89 question version; Minnesota Multiphasic Personality Inventory--2; Wechsler Adult Intelligence Scale--third edition; and verbal and visual memory tests as predictors demonstrated a different pattern of association with the factor and summary scores. We conclude that the Epilepsy Foundation Concerns Index is multidimensional, and using a global score based on all items may mask specific concerns that may be relevant when applied to individual patients.

What distinguishes individual stocks from the index?

NASA Astrophysics Data System (ADS)

Wagner, F.; Milaković, M.; Alfarano, S.

2010-01-01

Stochastic volatility models decompose the time series of financial returns into the product of a volatility factor and an iid noise factor. Assuming a slow dynamic for the volatility factor, we show via nonparametric tests that both the index as well as its individual stocks share a common volatility factor. While the noise component is Gaussian for the index, individual stock returns turn out to require a leptokurtic noise. Thus we propose a two-component model for stocks, given by the sum of Gaussian noise, which reflects market-wide fluctuations, and Laplacian noise, which incorporates firm-specific factors such as firm profitability or growth performance, both of which are known to be Laplacian distributed. In the case of purely Gaussian noise, the chi-squared probability for the density of individual stock returns is typically on the order of 10-20, while it increases to values of O(1) by adding the Laplace component.

Association between serum magnesium and common complications of diabetes mellitus.

PubMed

Zhang, Yiyan; Li, Qin; Xin, Yi; Lv, Weiqi; Ge, Chuanbin

2018-01-01

Magnesium ion, as important cation in the human body, involved in various enzymatic reactions, glucose transport and insulin release. Now diabetes mellitus and diabetic complications have become important public health problems around the world. This paper explores the association between concentration levels of serum magnesium and common complications and comorbidities of diabetes mellitus and other biochemical indexes. There are 1217 eligible patients selected from 14,317 cases of diabetic hospitalization patients from January 2010 to December 2011. Random forest algorithm was applied to assess the importance of various biochemical indexes and to perform diabetic complications prediction. The research results showed that low concentration of serum magnesium and four common diabetic complications - diabetic retinopathy, diabetic nephropathy, diabetic neuropathy and diabetic macroangiopathy - exists association, but no obvious correlation with other comorbidities like hypertension. The specific factors of four common diabetic complications were selected from the biochemical indexes to provide a reference direction for further research.

Air Velocity Mapping of Environmental Test Chambers

DTIC Science & Technology

1989-07-01

variable that must be measured for the evaluations of the air diffusion performance index (ADPI), or the thermal comfort indices such as predicted mean...altered. The impact of asymmetrical airflow patterns undoubtedly affect human thermal comfort votes. The standardized 6 technique described in this...report could be easily employed prior to or along with specific studies requiring precise air velocity data, and coupled with human thermal comfort surveys

Active Conceptual Modeling of Learning Workshop 10-12 May 2006

DTIC Science & Technology

2007-03-01

digital libraries. This project is working in partnership with the health portal for the Healthcare Ministry in Denmark and with the natural...also the principal investigator for an NSF-funded Digital Government project seeking to improve indexing and retrieval performance in domain-specific...solutions. It is being used in governmental, environmental, military, real-estate, health and many more applications. Each field faces common tasks of

Artificial Neural Networks Equivalent to Fuzzy Algebra T-Norm Conjunction Operators

NASA Astrophysics Data System (ADS)

Iliadis, L. S.; Spartalis, S. I.

2007-12-01

This paper describes the construction of three Artificial Neural Networks with fuzzy input and output, imitating the performance of fuzzy algebra conjunction operators. More specifically, it is applied over the results of a previous research effort that used T-Norms in order to produce a characteristic torrential risk index that unified the partial risk indices for the area of Xanthi. Each one of the three networks substitutes a T-Norm and consequently they can be used as equivalent operators. This means that ANN performing Fuzzy Algebra operations can be designed and developed.

WISC-III cognitive profiles in children with developmental dyslexia: specific cognitive disability and diagnostic utility.

PubMed

Moura, Octávio; Simões, Mário R; Pereira, Marcelino

2014-02-01

This study analysed the usefulness of the Wechsler Intelligence Scale for Children-Third Edition in identifying specific cognitive impairments that are linked to developmental dyslexia (DD) and the diagnostic utility of the most common profiles in a sample of 100 Portuguese children (50 dyslexic and 50 normal readers) between the ages of 8 and 12 years. Children with DD exhibited significantly lower scores in the Verbal Comprehension Index (except the Vocabulary subtest), Freedom from Distractibility Index (FDI) and Processing Speed Index subtests, with larger effect sizes than normal readers in Information, Arithmetic and Digit Span. The Verbal-Performance IQs discrepancies, Bannatyne pattern and the presence of FDI; Arithmetic, Coding, Information and Digit Span subtests (ACID) and Symbol Search, Coding, Arithmetic and Digit Span subtests (SCAD) profiles (full or partial) in the lowest subtests revealed a low diagnostic utility. However, the receiver operating characteristic curve and the optimal cut-off score analyses of the composite ACID; FDI and SCAD profiles scores showed moderate accuracy in correctly discriminating dyslexic readers from normal ones. These results suggested that in the context of a comprehensive assessment, the Wechsler Intelligence Scale for Children-Third Edition provides some useful information about the presence of specific cognitive disabilities in DD. Practitioner Points. Children with developmental dyslexia revealed significant deficits in the Wechsler Intelligence Scale for Children-Third Edition subtests that rely on verbal abilities, processing speed and working memory. The composite Arithmetic, Coding, Information and Digit Span subtests (ACID); Freedom from Distractibility Index and Symbol Search, Coding, Arithmetic and Digit Span subtests (SCAD) profile scores showed moderate accuracy in correctly discriminating dyslexics from normal readers. Wechsler Intelligence Scale for Children-Third Edition may provide some useful information about the presence of specific cognitive disabilities in developmental dyslexia. Copyright © 2013 John Wiley & Sons, Ltd.

Performance of the Duke Religion Index and the spiritual well-being scale in online samples of men who have sex with men.

PubMed

Wilkerson, J Michael; Smolensk, Derek J; Brady, Sonya S; Rosser, B R Simon

2013-06-01

Religiosity is associated with behaviors that reduce the risk of HIV/STI infection among general-population and heterosexual-specific samples. Whether this association is similar to homosexual persons is unknown. Measures of religiosity have not been evaluated psychometrically among men who have sex with men (MSM), a population who, because of stigma, experience religiosity differently than heterosexual persons. We assessed the duke religion index and the spiritual well-being in two samples of MSM. Neither instrument produced adequate model fit. To study the association between religiosity and HIV/STI risk behaviors among MSM, scales are needed that measure the religious and spiritual experiences of MSM.

Solid fuel grindability: a literature review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hills, L.

2007-07-01

The most commonly used measurement of coal grindability is the Hardgrove Grindability Index (HGI) however, many solid fuels do not exhibit the grinding performance predicted by this index. Parameters which can influence grindability and possibly lead to inaccurate prediction of grindability as determined by HGI include: composition and texture, mineral components, brittleness, and rank (which establishes carbon, volatile matter, and moisture contents). Descriptions of these parameters are provided. Alternative measurements of grindability from literature are presented. The most promising may be a revision on the standard HGI, in which a mill capacity factor is derived from the number of millmore » rotations to crush coal to a specific fineness. 88 refs.« less

The association of inflammatory markers and periodontal indexes with the risk of coronary heart disease in Chinese patients with type 2 diabetes mellitus.

PubMed

Chen, Ling; Wei, Bin; Xu, Liang; Wu, Yun

2018-01-01

The present study was designed to investigate the association of four inflammatory markers and five periodontal indexes with the risk of coronary heart disease (CHD) in 131 patients with type 2 diabetes mellitus (T2DM). All subjects were inpatients, including 63 T2DM patients with comorbid CHD ("cases") and 68 T2DM patients without CHD ("controls"). The diagnosis of CHD is based on coronary angiography. Peripheral blood concentrations of high sensitivity C-reactive protein (hs-CRP) (11.51 vs. 10.39 mg/L), leptin (24.60 vs. 21.22 ng/L) and visfatin (65.92 vs. 57.62 ng/L) were significantly higher in cases than in controls (P = .033, 0.041 and 0.041, respectively). The levels of three periodontal indexes - probing pocket depth, attachment loss (AL) and sulcus bleeding index, were significantly higher in cases than in controls, especially for periodontal AL (3.60 mm vs. 3.29 mm, P = .002). A Forward logistic regression was performed for selection, and specifically hs-CRP, leptin, visfatin and periodontal AL were found to be associated with the significant risk of CHD (odds ratio: 1.16, 1.07, 1.03 and 2.04; P = .025, .022, .022 and .010, respectively). Importantly, the benefits of inflammatory markers and periodontal indexes over basic risk factors were significant (likelihood ratio test) and obvious (decision curve analysis). A nomogram was delineated based on significant variables, and it had good accuracy (C-index: 0.801, P < .001). Our findings support the significant contribution of inflammatory markers and periodontal indexes to the pathogenesis of CHD in T2DM. Specifically, hs-CRP, leptin, visfatin and periodontal AL were identified as significant contributors. Copyright © 2017 Elsevier B.V. All rights reserved.

Electrical Double Layer-Induced Ion Surface Accumulation for Ultrasensitive Refractive Index Sensing with Nanostructured Porous Silicon Interferometers.

PubMed

Mariani, Stefano; Strambini, Lucanos Marsilio; Barillaro, Giuseppe

2018-03-23

Herein, we provide the first experimental evidence on the use of electrical double layer (EDL)-induced accumulation of charged ions (using both Na + and K + ions in water as the model) onto a negatively charged nanostructured surface (e.g., thermally growth SiO 2 )-Ion Surface Accumulation, ISA-as a means of improving performance of nanostructured porous silicon (PSi) interferometers for optical refractometric applications. Nanostructured PSi interferometers are very promising optical platforms for refractive index sensing due to PSi huge specific surface (hundreds of m 2 per gram) and low preparation cost (less than $0.01 per 8 in. silicon wafer), though they have shown poor resolution ( R) and detection limit (DL) (on the order of 10 -4 -10 -5 RIU) compared to other plasmonic and photonic platforms ( R and DL on the order of 10 -7 -10 -8 RIU). This can be ascribed to both low sensitivity and high noise floor of PSi interferometers when bulk refractive index variation of the solution infiltrating the nanopores either approaches or is below 10 -4 RIU. Electrical double layer-induced ion surface accumulation (EDL-ISA) on oxidized PSi interferometers allows the interferometer output signal (spectral interferogram) to be impressively amplified at bulk refractive index variation below 10 -4 RIU, increasing, in turn, sensitivity up to 2 orders of magnitude and allowing reliable measurement of refractive index variations to be carried out with both DL and R of 10 -7 RIU. This represents a 250-fold-improvement (at least) with respect to the state-of-the-art literature on PSi refractometers and pushes PSi interferometer performance to that of state-of-the-art ultrasensitive photonics/plasmonics refractive index platforms.

Gait performance is not influenced by working memory when walking at a self-selected pace.

PubMed

Grubaugh, Jordan; Rhea, Christopher K

2014-02-01

Gait performance exhibits patterns within the stride-to-stride variability that can be indexed using detrended fluctuation analysis (DFA). Previous work employing DFA has shown that gait patterns can be influenced by constraints, such as natural aging or disease, and they are informative regarding a person's functional ability. Many activities of daily living require concurrent performance in the cognitive and gait domains; specifically working memory is commonly engaged while walking, which is considered dual-tasking. It is unknown if taxing working memory while walking influences gait performance as assessed by DFA. This study used a dual-tasking paradigm to determine if performance decrements are observed in gait or working memory when performed concurrently. Healthy young participants (N = 16) performed a working memory task (automated operation span task) and a gait task (walking at a self-selected speed on a treadmill) in single- and dual-task conditions. A second dual-task condition (reading while walking) was included to control for visual attention, but also introduced a task that taxed working memory over the long term. All trials involving gait lasted at least 10 min. Performance in the working memory task was indexed using five dependent variables (absolute score, partial score, speed error, accuracy error, and math error), while gait performance was indexed by quantifying the mean, standard deviation, and DFA α of the stride interval time series. Two multivariate analyses of variance (one for gait and one for working memory) were used to examine performance in the single- and dual-task conditions. No differences were observed in any of the gait or working memory dependent variables as a function of task condition. The results suggest the locomotor system is adaptive enough to complete a working memory task without compromising gait performance when walking at a self-selected pace.

An Analytical Study on an Orthodontic Index: Index of Complexity, Outcome and Need (ICON)

PubMed Central

Torkan, Sepide; Pakshir, Hamid Reza; Fattahi, Hamid Reza; Oshagh, Morteza; Momeni Danaei, Shahla; Salehi, Parisa; Hedayati, Zohreh

2015-01-01

Statement of the Problem The validity of the Index of Complexity, Outcome and Need (ICON) which is an orthodontic index developed and introduced in 2000 should be studied in different ethnic groups. Purpose The aim of this study was to perform an analysis on the ICON and to verify whether this index is valid for assessing both the need and complexity of orthodontic treatment in Iran. Materials and Method Five orthodontists were asked to score pre-treatment diagnostic records of 100 patients with a uniform distribution of different types of malocclusions determined by Dental Health Component of the Index of Treatment Need. A calibrated examiner also assessed the need for orthodontic treatment and complexity of the cases based on the ICON index as well as the Index of Orthodontic Treatment Need (IOTN). 10 days later, 25% of the cases were re-scored by the panel of experts and the calibrated orthodontist. Results The weighted kappa revealed the inter-examiner reliability of the experts to be 0.63 and 0.51 for the need and complexity components, respectively. ROC curve was used to assess the validity of the index. A new cut-off point was adjusted at 35 in lieu of 43 as the suggested cut-off point. This cut-off point showed the highest level of sensitivity and specificity in our society for orthodontic treatment need (0.77 and 0.78, respectively), but it failed to define definite ranges for the complexity of treatment. Conclusion ICON is a valid index in assessing the need for treatment in Iran when the cut-off point is adjusted to 35. As for complexity of treatment, the index is not validated for our society. It seems that ICON is a well-suited substitute for the IOTN index. PMID:26331142

Energy index decomposition methodology at the plant level

NASA Astrophysics Data System (ADS)

Kumphai, Wisit

Scope and method of study. The dissertation explores the use of a high level energy intensity index as a facility-level energy performance monitoring indicator with a goal of developing a methodology for an economically based energy performance monitoring system that incorporates production information. The performance measure closely monitors energy usage, production quantity, and product mix and determines the production efficiency as a part of an ongoing process that would enable facility managers to keep track of and, in the future, be able to predict when to perform a recommissioning process. The study focuses on the use of the index decomposition methodology and explored several high level (industry, sector, and country levels) energy utilization indexes, namely, Additive Log Mean Divisia, Multiplicative Log Mean Divisia, and Additive Refined Laspeyres. One level of index decomposition is performed. The indexes are decomposed into Intensity and Product mix effects. These indexes are tested on a flow shop brick manufacturing plant model in three different climates in the United States. The indexes obtained are analyzed by fitting an ARIMA model and testing for dependency between the two decomposed indexes. Findings and conclusions. The results concluded that the Additive Refined Laspeyres index decomposition methodology is suitable to use on a flow shop, non air conditioned production environment as an energy performance monitoring indicator. It is likely that this research can be further expanded in to predicting when to perform a recommissioning process.

Examining the Time Course of Indexical Specificity Effects in Spoken Word Recognition

ERIC Educational Resources Information Center

McLennan, Conor T.; Luce, Paul A.

2005-01-01

Variability in talker identity and speaking rate, commonly referred to as indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. The present study examines the time course of indexical specificity effects to evaluate the hypothesis that such effects occur relatively late in the perceptual processing of…

Computational intelligence for the Balanced Scorecard: studying performance trends of hemodialysis clinics.

PubMed

Cattinelli, Isabella; Bolzoni, Elena; Chermisi, Milena; Bellocchio, Francesco; Barbieri, Carlo; Mari, Flavio; Amato, Claudia; Menzer, Marcus; Stopper, Andrea; Gatti, Emanuele

2013-07-01

The Balanced Scorecard (BSC) is a general, widely employed instrument for enterprise performance monitoring based on the periodic assessment of strategic Key Performance Indicators that are scored against preset targets. The BSC is currently employed as an effective management support tool within Fresenius Medical Care (FME) and is routinely analyzed via standard statistical methods. More recently, the application of computational intelligence techniques (namely, self-organizing maps) to BSC data has been proposed as a way to enhance the quantity and quality of information that can be extracted from it. In this work, additional methods are presented to analyze the evolution of clinic performance over time. Performance evolution is studied at the single-clinic level by computing two complementary indexes that measure the proportion of time spent within performance clusters and improving/worsening trends. Self-organizing maps are used in conjunction with these indexes to identify the specific drivers of the observed performance. The performance evolution for groups of clinics is modeled under a probabilistic framework by resorting to Markov chain properties. These allow a study of the probability of transitioning between performance clusters as time progresses for the identification of the performance level that is expected to become dominant over time. We show the potential of the proposed methods through illustrative results derived from the analysis of BSC data of 109 FME clinics in three countries. We were able to identify the performance drivers for specific groups of clinics and to distinguish between countries whose performances are likely to improve from those where a decline in performance might be expected. According to the stationary distribution of the Markov chain, the expected trend is best in Turkey (where the highest performance cluster has the highest probability, P=0.46), followed by Portugal (where the second best performance cluster dominates, with P=0.50), and finally Italy (where the second best performance cluster has P=0.34). These results highlight the ability of the proposed methods to extract insights about performance trends that cannot be easily extrapolated using standard analyses and that are valuable in directing management strategies within a continuous quality improvement policy. Copyright © 2013 Elsevier B.V. All rights reserved.

Reliability, construct validity, and responsiveness of the neck disability index, patient-specific functional scale, and numeric pain rating scale in patients with cervical radiculopathy.

PubMed

Young, Ian A; Cleland, Joshua A; Michener, Lori A; Brown, Chris

2010-10-01

To examine the psychometric properties of the Neck Disability Index, Patient-Specific Functional Scale, and the Numeric Pain Rating Scale in a cohort of patients with cervical radiculopathy. A single-group repeated-measures design. Patients (n = 165) presenting to physical therapy with cervical radiculopathy completed the Neck Disability Index, Patient-Specific Functional Scale, and Numeric Pain Rating Scale at the baseline examination and at a follow-up. At the time of follow-up, all patients also completed the Global Rating of Change, which was used to dichotomize patients as improved or stable. Baseline and follow-up scores were used to determine the test-retest reliability, construct validity, and minimal levels of detectable and clinically important change for the Neck Disability Index, Patient-Specific Functional Scale, and Numeric Pain Rating Scale. Both the Neck Disability Index and Numeric Pain Rating Scale exhibited fair test-retest reliability, whereas the Patient-Specific Functional Scale exhibited poor reliability in patients with cervical radiculopathy. All three outcome measures showed adequate responsiveness in this patient population. The minimal detectable change was 13.4 for the Neck Disability Index, 3.3 for the Patient-Specific Functional Scale, and 4.1 for the Numeric Pain Rating Scale. The threshold for the minimal clinically important difference was 8.5 for the Neck Disability Index and 2.2 for both the Patient-Specific Functional Scale and Numeric Pain Rating Scale. In light of the varied distribution of symptoms in patients with cervical radiculopathy, future studies should investigate the psychometric properties of other neck-related disability measures in this patient population.

Community-wide validation of geospace model local K-index predictions to support model transition to operations

NASA Astrophysics Data System (ADS)

Glocer, A.; Rastätter, L.; Kuznetsova, M.; Pulkkinen, A.; Singer, H. J.; Balch, C.; Weimer, D.; Welling, D.; Wiltberger, M.; Raeder, J.; Weigel, R. S.; McCollough, J.; Wing, S.

2016-07-01

We present the latest result of a community-wide space weather model validation effort coordinated among the Community Coordinated Modeling Center (CCMC), NOAA Space Weather Prediction Center (SWPC), model developers, and the broader science community. Validation of geospace models is a critical activity for both building confidence in the science results produced by the models and in assessing the suitability of the models for transition to operations. Indeed, a primary motivation of this work is supporting NOAA/SWPC's effort to select a model or models to be transitioned into operations. Our validation efforts focus on the ability of the models to reproduce a regional index of geomagnetic disturbance, the local K-index. Our analysis includes six events representing a range of geomagnetic activity conditions and six geomagnetic observatories representing midlatitude and high-latitude locations. Contingency tables, skill scores, and distribution metrics are used for the quantitative analysis of model performance. We consider model performance on an event-by-event basis, aggregated over events, at specific station locations, and separated into high-latitude and midlatitude domains. A summary of results is presented in this report, and an online tool for detailed analysis is available at the CCMC.

Community-Wide Validation of Geospace Model Local K-Index Predictions to Support Model Transition to Operations

NASA Technical Reports Server (NTRS)

Glocer, A.; Rastaetter, L.; Kuznetsova, M.; Pulkkinen, A.; Singer, H. J.; Balch, C.; Weimer, D.; Welling, D.; Wiltberger, M.; Raeder, J.;

Distinct patterns of functional brain connectivity correlate with objective performance and subjective beliefs

PubMed Central

Barttfeld, Pablo; Wicker, Bruno; McAleer, Phil; Belin, Pascal; Cojan, Yann; Graziano, Martín; Leiguarda, Ramón; Sigman, Mariano

2013-01-01

The degree of correspondence between objective performance and subjective beliefs varies widely across individuals. Here we demonstrate that functional brain network connectivity measured before exposure to a perceptual decision task covaries with individual objective (type-I performance) and subjective (type-II performance) accuracy. Increases in connectivity with type-II performance were observed in networks measured while participants directed attention inward (focus on respiration), but not in networks measured during states of neutral (resting state) or exogenous attention. Measures of type-I performance were less sensitive to the subjects’ specific attentional states from which the networks were derived. These results suggest the existence of functional brain networks indexing objective performance and accuracy of subjective beliefs distinctively expressed in a set of stable mental states. PMID:23801762

Imaging modalities for characterising focal pancreatic lesions.

PubMed

Best, Lawrence Mj; Rawji, Vishal; Pereira, Stephen P; Davidson, Brian R; Gurusamy, Kurinchi Selvan

2017-04-17

Increasing numbers of incidental pancreatic lesions are being detected each year. Accurate characterisation of pancreatic lesions into benign, precancerous, and cancer masses is crucial in deciding whether to use treatment or surveillance. Distinguishing benign lesions from precancerous and cancerous lesions can prevent patients from undergoing unnecessary major surgery. Despite the importance of accurately classifying pancreatic lesions, there is no clear algorithm for management of focal pancreatic lesions. To determine and compare the diagnostic accuracy of various imaging modalities in detecting cancerous and precancerous lesions in people with focal pancreatic lesions. We searched the CENTRAL, MEDLINE, Embase, and Science Citation Index until 19 July 2016. We searched the references of included studies to identify further studies. We did not restrict studies based on language or publication status, or whether data were collected prospectively or retrospectively. We planned to include studies reporting cross-sectional information on the index test (CT (computed tomography), MRI (magnetic resonance imaging), PET (positron emission tomography), EUS (endoscopic ultrasound), EUS elastography, and EUS-guided biopsy or FNA (fine-needle aspiration)) and reference standard (confirmation of the nature of the lesion was obtained by histopathological examination of the entire lesion by surgical excision, or histopathological examination for confirmation of precancer or cancer by biopsy and clinical follow-up of at least six months in people with negative index tests) in people with pancreatic lesions irrespective of language or publication status or whether the data were collected prospectively or retrospectively. Two review authors independently searched the references to identify relevant studies and extracted the data. We planned to use the bivariate analysis to calculate the summary sensitivity and specificity with their 95% confidence intervals and the hierarchical summary receiver operating characteristic (HSROC) to compare the tests and assess heterogeneity, but used simpler models (such as univariate random-effects model and univariate fixed-effect model) for combining studies when appropriate because of the sparse data. We were unable to compare the diagnostic performance of the tests using formal statistical methods because of sparse data. We included 54 studies involving a total of 3,196 participants evaluating the diagnostic accuracy of various index tests. In these 54 studies, eight different target conditions were identified with different final diagnoses constituting benign, precancerous, and cancerous lesions. None of the studies was of high methodological quality. None of the comparisons in which single studies were included was of sufficiently high methodological quality to warrant highlighting of the results. For differentiation of cancerous lesions from benign or precancerous lesions, we identified only one study per index test. The second analysis, of studies differentiating cancerous versus benign lesions, provided three tests in which meta-analysis could be performed. The sensitivities and specificities for diagnosing cancer were: EUS-FNA: sensitivity 0.79 (95% confidence interval (CI) 0.07 to 1.00), specificity 1.00 (95% CI 0.91 to 1.00); EUS: sensitivity 0.95 (95% CI 0.84 to 0.99), specificity 0.53 (95% CI 0.31 to 0.74); PET: sensitivity 0.92 (95% CI 0.80 to 0.97), specificity 0.65 (95% CI 0.39 to 0.84). The third analysis, of studies differentiating precancerous or cancerous lesions from benign lesions, only provided one test (EUS-FNA) in which meta-analysis was performed. EUS-FNA had moderate sensitivity for diagnosing precancerous or cancerous lesions (sensitivity 0.73 (95% CI 0.01 to 1.00) and high specificity 0.94 (95% CI 0.15 to 1.00), the extremely wide confidence intervals reflecting the heterogeneity between the studies). The fourth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (dysplasia) provided three tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing invasive carcinoma were: CT: sensitivity 0.72 (95% CI 0.50 to 0.87), specificity 0.92 (95% CI 0.81 to 0.97); EUS: sensitivity 0.78 (95% CI 0.44 to 0.94), specificity 0.91 (95% CI 0.61 to 0.98); EUS-FNA: sensitivity 0.66 (95% CI 0.03 to 0.99), specificity 0.92 (95% CI 0.73 to 0.98). The fifth analysis, of studies differentiating cancerous (high-grade dysplasia or invasive carcinoma) versus precancerous (low- or intermediate-grade dysplasia) provided six tests in which meta-analysis was performed. The sensitivities and specificities for diagnosing cancer (high-grade dysplasia or invasive carcinoma) were: CT: sensitivity 0.87 (95% CI 0.00 to 1.00), specificity 0.96 (95% CI 0.00 to 1.00); EUS: sensitivity 0.86 (95% CI 0.74 to 0.92), specificity 0.91 (95% CI 0.83 to 0.96); EUS-FNA: sensitivity 0.47 (95% CI 0.24 to 0.70), specificity 0.91 (95% CI 0.32 to 1.00); EUS-FNA carcinoembryonic antigen 200 ng/mL: sensitivity 0.58 (95% CI 0.28 to 0.83), specificity 0.51 (95% CI 0.19 to 0.81); MRI: sensitivity 0.69 (95% CI 0.44 to 0.86), specificity 0.93 (95% CI 0.43 to 1.00); PET: sensitivity 0.90 (95% CI 0.79 to 0.96), specificity 0.94 (95% CI 0.81 to 0.99). The sixth analysis, of studies differentiating cancerous (invasive carcinoma) from precancerous (low-grade dysplasia) provided no tests in which meta-analysis was performed. The seventh analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) provided two tests in which meta-analysis was performed. The sensitivity and specificity for diagnosing cancer were: CT: sensitivity 0.83 (95% CI 0.68 to 0.92), specificity 0.83 (95% CI 0.64 to 0.93) and MRI: sensitivity 0.80 (95% CI 0.58 to 0.92), specificity 0.81 (95% CI 0.53 to 0.95), respectively. The eighth analysis, of studies differentiating precancerous or cancerous (intermediate- or high-grade dysplasia or invasive carcinoma) from precancerous (low-grade dysplasia) or benign lesions provided no test in which meta-analysis was performed.There were no major alterations in the subgroup analysis of cystic pancreatic focal lesions (42 studies; 2086 participants). None of the included studies evaluated EUS elastography or sequential testing. We were unable to arrive at any firm conclusions because of the differences in the way that study authors classified focal pancreatic lesions into cancerous, precancerous, and benign lesions; the inclusion of few studies with wide confidence intervals for each comparison; poor methodological quality in the studies; and heterogeneity in the estimates within comparisons.

Cardiovascular response to dobutamine stress predicts outcome in severe sepsis and septic shock.

PubMed

Kumar, Anand; Schupp, Elizabeth; Bunnell, Eugene; Ali, Amjad; Milcarek, Barry; Parrillo, Joseph E

2008-01-01

During septic shock, resistance to the haemodynamic effects of catecholamine vasopressors and inotropes is a well-recognised marker of mortality risk. However, the specific cardiovascular or metabolic response elements that are most closely associated with outcome have not been well defined. The objective of this study was to assess cardiovascular and metabolic responses to dobutamine as correlates of outcome in patients with severe sepsis or septic shock. A prospective, non-randomised, non-blinded interventional study of graded dobutamine challenge (0, 5, 10, and 15 mug/kg/min) in adult patients who had undergone pulmonary artery catheterisation within 48 hours of onset of severe sepsis or septic shock (8 survivors/15 non-survivors) was performed. Radionuclide cineangiography during graded infusion was used to determine biventricular ejection fractions at each increment of dobutamine. In univariate analysis, a variety of cardiovascular or haemodynamic and oxygen transport or metabolic variables (at the point of maximum cardiac index response for a given subject) were associated with survival including: increased stroke volume index (p = 0.0003); right ventricular end-diastolic volume index (p = 0.0047); left ventricular stroke work index (p = 0.0054); oxygen delivery index (p = 0.0084); cardiac index (p = 0.0093); systolic blood pressure/left ventricular end-systolic volume index ratio (p = 0.0188); left ventricular ejection fraction (p = 0.0160); venous oxygen content (p = 0.0208); mixed venous oxygen saturation (p = 0.0234); pulse pressure (p = 0.0403); decreased pulmonary artery diastolic pressure (p = 0.0133); systemic vascular resistance index (p = 0.0154); extraction ratio (p = 0.0160); and pulmonary vascular resistance index (p = 0.0390). Increases of stroke volume index of greater than or less than 8.5 mL/m2 were concordant with survival or death in 21 of 23 cases. Multivariate profile construction showed stroke volume index as the dominant discriminating variable for survival with the systolic blood pressure/left ventricular end-systolic volume index ratio alone among all other variables significantly improving the model. Survivors maintain cardiac responsiveness to catecholamine stimulation during septic shock. Survival from severe sepsis or septic shock is associated with increased cardiac performance and contractility indices during dobutamine infusion. Further studies are required to determine whether these parameters are predictive of outcome in a larger severe sepsis/septic shock population.

Biomarkers S100B and neuron-specific enolase predict outcome in hypothermia-treated encephalopathic newborns*.

PubMed

Massaro, An N; Chang, Taeun; Baumgart, Stephen; McCarter, Robert; Nelson, Karin B; Glass, Penny

2014-09-01

To evaluate if serum S100B protein and neuron-specific enolase measured during therapeutic hypothermia are predictive of neurodevelopmental outcome at 15 months in children with neonatal encephalopathy. Prospective longitudinal cohort study. A level IV neonatal ICU in a freestanding children's hospital. Term newborns with moderate to severe neonatal encephalopathy referred for therapeutic hypothermia during the study period. Serum neuron-specific enolase and S100B were measured at 0, 12, 24, and 72 hours of hypothermia. Of the 83 infants enrolled, 15 (18%) died in the newborn period. Survivors were evaluated by the Bayley Scales of Infant Development-II at 15 months. Outcomes were assessed in 49 of 68 survivors (72%) at a mean age of 15.2 ± 2.7 months. Neurodevelopmental outcome was classified by Bayley Scales of Infant Development-II Mental Developmental Index and Psychomotor Developmental Index scores, reflecting cognitive and motor outcomes, respectively. Four-level outcome classifications were defined a priori: normal = Mental Developmental Index/Psychomotor Developmental Index within 1 SD (> 85), mild = Mental Developmental Index/Psychomotor Developmental Index less than 1 SD (70-85), moderate/severe = Mental Developmental Index/Psychomotor Developmental Index less than 2 SD (< 70), or died. Elevated serum S100B and neuron-specific enolase levels measured during hypothermia were associated with increasing outcome severity after controlling for baseline and socioeconomic characteristics in ordinal regression models. Adjusted odds ratios for cognitive outcome were 2.5 (95% CI, 1.3-4.8) for S100B and 2.1 (95% CI, 1.2-3.6) for neuron-specific enolase, and for motor outcome, 2.6 (95% CI, 1.2-5.6) for S100B and 2.1 (95% CI, 1.2-3.6) for neuron-specific enolase. Serum S100B and neuron-specific enolase levels in babies with neonatal encephalopathy are associated with neurodevelopmental outcome at 15 months. These putative biomarkers of brain injury may help direct care during therapeutic hypothermia.

Use of whole-genome sequencing and evaluation of the apparent sensitivity and specificity of antemortem tuberculosis tests in the investigation of an unusual outbreak of Mycobacterium bovis infection in a Michigan dairy herd.

PubMed

Bruning-Fann, Colleen S; Robbe-Austerman, Suelee; Kaneene, John B; Thomsen, Bruce V; Tilden, John D; Ray, Jean S; Smith, Richard W; Fitzgerald, Scott D; Bolin, Steven R; O'Brien, Daniel J; Mullaney, Thomas P; Stuber, Tod P; Averill, James J; Marks, David

2017-07-15

OBJECTIVE To describe use of whole-genome sequencing (WGS) and evaluate the apparent sensitivity and specificity of antemortem tuberculosis tests during investigation of an unusual outbreak of Mycobacterium bovis infection in a Michigan dairy herd. DESIGN Bovine tuberculosis (bTB) outbreak investigation. ANIMALS Cattle, cats, dog, and wildlife. PROCEDURES All cattle in the index dairy herd were screened for bTB with the caudal fold test (CFT), and cattle ≥ 6 months old were also screened with a γ-interferon (γIFN) assay. The index herd was depopulated along with all barn cats and a dog that were fed unpasteurized milk from the herd. Select isolates from M bovis-infected animals from the index herd and other bTB-affected herds underwent WGS. Wildlife around all affected premises was examined for bTB. RESULTS No evidence of bTB was found in any wildlife examined. Within the index herd, 53 of 451 (11.8%) cattle and 12 of 21 (57%) cats were confirmed to be infected with M bovis. Prevalence of M bovis-infected cattle was greatest among 4- to 7-month-old calves (16/49 [33%]) followed by adult cows (36/203 [18%]). The apparent sensitivity and specificity were 86.8% and 92.7% for the CFT and 80.4% and 96.5% for the γIFN assay when results for those tests were interpreted separately and 96.1% and 91.7% when results were interpreted in parallel. Results of WGS revealed that M bovis-infected barn cats and cattle from the index herd and 6 beef operations were infected with the same strain of M bovis. Of the 6 bTB-affected beef operations identified during the investigation, 3 were linked to the index herd only by WGS results; there was no record of movement of livestock or waste milk from the index herd to those operations. CONCLUSIONS AND CLINICAL RELEVANCE Whole-genome sequencing enhanced the epidemiological investigation and should be used in all disease investigations. Performing the CFT and γIFN assay in parallel improved the antemortem ability to detect M bovis-infected animals. Contact with M bovis-infected cattle and contaminated milk were major risk factors for transmission of bTB within and between herds of this outbreak.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mann, S.J.; Pickering, T.G.; Sos, T.A.

The purpose of this study was to determine the sensitivity, specificity, and clinical usefulness of renography performed in combination with captopril administration (captopril renography) in diagnosing renal artery stenosis. Fifty-five patients with suspected renal artery stenosis underwent renography prior to performance of renal angiography. Renography was performed on two consecutive days using technetium-99m-diethylenetiamine pentaacetic acid (DTPA) as an index of glomerular filtration rate and iodine-131-orthoiodohippurate (OIH) as an index of renal blood flow. Captopril (25 mg orally, crushed) was administered 1 hour before the second study. Renal artery stenosis was defined as a stenosis exceeding 70%. Renographic criteria were thenmore » established, retrospectively, to differentiate renal artery stenosis from essential hypertension based on (1) asymmetry of function and (2) the presence of captopril-induced changes. Renal artery stenosis was detected in 35 of 55 patients (21 with unilateral and 14 with bilateral stenosis). Three criteria were established for diagnosing renal artery stenosis: (1) a percent uptake of DTPA by the affected kidney of less than 40% of the combined bilateral uptake, (2) a delayed time to peak uptake of DTPA, which was more than 5 minutes longer in the affected kidney than in the contralateral kidney, (3) a delayed excretion of DTPA, with retention at 15 minutes, as a fraction of peak activity, more than 20% greater than in the contralateral kidney. The presence of one or more of these criteria was diagnostic of renal artery stenosis, with a sensitivity and specificity of 71% and 75%, respectively before captopril administration, and 94% and 95% after captopril administration. Lesser degrees of asymmetry (i.e., uptake of 40% to 50%) had very poor diagnostic specificity.« less

SleepMinder: an innovative contact-free device for the estimation of the apnoea-hypopnoea index.

PubMed

Zaffaroni, Alberto; de Chazal, Philip; Heneghan, Conor; Boyle, Patricia; Mppm, Patricia Ronayne; McNicholas, Walter T

2009-01-01

We describe an innovative sensor technology (SleepMinder) for contact-less and convenient measurement of sleep and breathing in the home. The system is based on a novel non-contact biomotion sensor and proprietary automated analysis software. The biomotion sensor uses an ultra low-power radio-frequency transceiver to sense the movement and respiration of a subject. Proprietary software performs a variety of signal analysis tasks including respiration analysis, sleep quality measurement and sleep apnea assessment. This paper measures the performance of SleepMinder as a device for the monitoring of sleep-disordered breathing (SDB) and the provision of an estimate of the apnoea-hypopnoea index (AHI). The SleepMinder was tested against expert manually scored PSG data of patients gathered in an accredited sleep laboratory. The comparison of SleepMinder to this gold standard was performed across overnight recordings of 129 subjects with suspected SDB. The dataset had a wide demographic profile with the age ranging between 20 and 81 years. Body weight included subjects with normal weight through to the very obese (Body Mass Index: 21-44 kg/m(2)). SDB severity ranged from subjects free of SDB to those with severe SDB (AHI: 0.8-96 events/hours). SleepMinder's AHI estimation has a correlation of 91% and can detect clinically significant SDB (AHI>15) with a sensitivity of 89% and a specificity of 92%.

Predicting preference-based SF-6D index scores from the SF-8 health survey.

PubMed

Wang, P; Fu, A Z; Wee, H L; Lee, J; Tai, E S; Thumboo, J; Luo, N

2013-09-01

To develop and test functions for predicting the preference-based SF-6D index scores from the SF-8 health survey. This study was a secondary analysis of data collected in a population health survey in which respondents (n = 7,529) completed both the SF-36 and the SF-8 questionnaires. We examined seven ordinary least-square estimators for their performance in predicting SF-6D scores from the SF-8 at both the individual and the group levels. In general, all functions performed similarly well in predicting SF-6D scores, and the predictions at the group level were better than predictions at the individual level. At the individual level, 42.5-51.5% of prediction errors were smaller than the minimally important difference (MID) of the SF-6D scores, depending on the function specifications, while almost all prediction errors of the tested functions were smaller than the MID of SF-6D at the group level. At both individual and group levels, the tested functions predicted lower than actual scores at the higher end of the SF-6D scale. Our study developed functions to generate preference-based SF-6D index scores from the SF-8 health survey, the first of its kind. Further research is needed to evaluate the performance and validity of the prediction functions.

Measurement Properties of Performance-Specific Pain Ratings of Patients Awaiting Total Joint Arthroplasty as a Consequence of Osteoarthritis

PubMed Central

Stratford, Paul W.; Kennedy, Deborah M.; Woodhouse, Linda J.; Spadoni, Gregory

2008-01-01

Purpose: To estimate the test–retest reliability of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain sub-scale and performance-specific assessments of pain, as well as the association between these measures for patients awaiting primary total hip or knee arthroplasty as a consequence of osteoarthritis. Methods: A total of 164 patients awaiting unilateral primary hip or knee arthroplasty completed four performance measures (self-paced walk, timed up and go, stair test, six-minute walk) and the WOMAC. Scores for 22 of these patients provided test–retest reliability data. Estimates of test–retest reliability (Type 2,1 intraclass correlation coefficient [ICC] and standard error of measurement [SEM]) and the association between measures were examined. Results: ICC values for individual performance-specific pain ratings were between 0.70 and 0.86; SEM values were between 0.97 and 1.33 pain points. ICC estimates for the four-item performance pain ratings and the WOMAC pain sub-scale were 0.82 and 0.57 respectively. The correlation between the sum of the pain scores for the four performance measures and the WOMAC pain sub-scale was 0.62. Conclusion: Reliability estimates for the performance-specific assessments of pain using the numeric pain rating scale were consistent with values reported for patients with a spectrum of musculoskeletal conditions. The reliability estimate for the WOMAC pain sub-scale was lower than typically reported in the literature. The level of association between the WOMAC pain sub-scale and the various performance-specific pain scales suggests that the scores can be used interchangeably when applied to groups but not for individual patients. PMID:20145758

Assessment of hospital performance with a case-mix standardized mortality model using an existing administrative database in Japan.

PubMed

Miyata, Hiroaki; Hashimoto, Hideki; Horiguchi, Hiromasa; Fushimi, Kiyohide; Matsuda, Shinya

2010-05-19

Few studies have examined whether risk adjustment is evenly applicable to hospitals with various characteristics and case-mix. In this study, we applied a generic prediction model to nationwide discharge data from hospitals with various characteristics. We used standardized data of 1,878,767 discharged patients provided by 469 hospitals from July 1 to October 31, 2006. We generated and validated a case-mix in-hospital mortality prediction model using 50/50 split sample validation. We classified hospitals into two groups based on c-index value (hospitals with c-index > or = 0.8; hospitals with c-index < 0.8) and examined differences in their characteristics. The model demonstrated excellent discrimination as indicated by the high average c-index and small standard deviation (c-index = 0.88 +/- 0.04). Expected mortality rate of each hospital was highly correlated with observed mortality rate (r = 0.693, p < 0.001). Among the studied hospitals, 446 (95%) had a c-index of >/=0.8 and were classified as the higher c-index group. A significantly higher proportion of hospitals in the lower c-index group were specialized hospitals and hospitals with convalescent wards. The model fits well to a group of hospitals with a wide variety of acute care events, though model fit is less satisfactory for specialized hospitals and those with convalescent wards. Further sophistication of the generic prediction model would be recommended to obtain optimal indices to region specific conditions.

Denaturation process of laccase in various media by refractive index measurements.

PubMed

Saoudi, O; Ghaouar, N; Ben Salah, S; Othman, T

2017-09-01

In this work, we are interested in the denaturation process of a laccase from Tramates versicolor via the determination of the refractive index, the refractive index increment and the specific volume in various media. The measurements were carried out using an Abbe refractometer. We have shown that the refractive index increment values obtained from the slope of the variation of the refractive index vs. Concentration are outside the range refractive index increments of proteins. To correct the results, we have followed the theoretical predictions based on the knowledge of the protein refractive index from its amino acids composition. The denaturation process was studied by calculating the specific volume variation where its determination was related to the Gladstone-Dale and the Lorentz-Lorentz models.

Biological Variation and Reference Change Value Data for Serum Neuron-Specific Enolase in a Turkish Population.

PubMed

Matyar, Selcuk; Goruroglu Ozturk, Ozlem; Ziyanoglu Karacor, Esin; Yuzbasioglu Ariyurek, Sedefgul; Sahin, Gulhan; Kibar, Filiz; Yaman, Akgun; Inal, Tamer

2016-11-01

Neuron-specific enolase (NSE) is a recognized biomarker for the assessment of cerebral injury in neurological disorders. This study aims to report a definitive assessment of the biological variation (BV) components of this biomarker, including within-subject BV (CVI), between-subject BV (CVG), index of individuality (II), and reference change value (RCV), in a cohort of Turkish participants using an experimental protocol. Six blood specimens were collected from each of the 13 apparently healthy volunteers (seven women, six men; ranging in age from 23 to 36) on the same day, every 2 weeks for 2 months. Serum specimens were stored at -20°C until analysis. Neuron-specific enolase levels were evaluated in serum samples using an electrochemiluminescence (ECLIA) immunoassay kit with a Roche Cobas e 411 auto-analyser. ANOVA test was used to calculate the variations. The CVI and CVG for NSE were 21.5% and 28.8%, respectively. Analytical variation (CVA) was calculated as 10.2%. Additionally, II and RCV were calculated as 0.74 and 66% (95% confident interval, CI), respectively. As the performance index (PI) was found to be less than 2 (PI = 0.95), it is concluded that the NSE measurements have a desirable performance for analytical imprecision. Since the II was found to be less than 1 (II: 0.74), the reference values will be of little use. Thus, RCV would provide better information for deciding whether a significant change has occurred. © 2016 Wiley Periodicals, Inc.

A switchable magnetic low-index metamaterial for use in a dynamically reconfigurable beam-scanning lens antenna with a single feed

NASA Astrophysics Data System (ADS)

Turpin, Jeremiah Paul

Metamaterials and Transformation Optics (TO) have been used to design and implement many novel electromagnetic devices that can achieve effects not possible using conventional materials. Compact high-gain antennas are one of the more popular and successful emerging applications for the new TO and metamaterial design approaches. This dissertation details an extension of uniaxial near-zero-index metamaterial lenses through the incorporation of a tunable or reconfigurable metamaterial as a replacement for the static metamaterial of the original antenna. A design is presented for a beam-scanning TO lens that allows an arbitrary number of beams at controlled magnitudes to be dynamically synthesized from a single omnidirectional source, unlike the equivalent antenna constructed using an array. A cylindrical slab of zero-index magnetic metamaterial controls the radiation pattern by altering the effective shape of the lens through switching of selected regions 'off' to emulate free-space conditions. A design for a switchable metamaterial is presented that allows for digital control over its bulk properties, from near-zero-index to near-free-space at the targeted operational frequency. Extensive modeling and simulations were performed for the design of the lens and metamaterial and during the analysis of measurement results. Initial prototypes of the tunable metamaterial were fabricated and characterized to confirm the original measurements, and the design updated to incorporate the measured data. These measurements were performed using custom test fixtures manufactured specifically for this project. Finally, a simplified prototype lens was manufactured and characterized in an anechoic as a proof-of-concept for the design. This dissertation presents the lens and metamaterial specifications, as well as the design process and considerations that were determined for practical tunable and reconfigurable metamaterials. Although the focus is on the particular example of the beam-scanning reconfigurable antenna, the analysis and modeling methods presented here are applicable to any reconfigurable metamaterial application.

[Visual perception abilities in children with reading disabilities].

PubMed

Werpup-Stüwe, Lina; Petermann, Franz

2015-05-01

Visual perceptual abilities are increasingly being neglected in research concerning reading disabilities. This study measures the visual perceptual abilities of children with disabilities in reading. The visual perceptual abilities of 35 children with specific reading disorder and 30 controls were compared using the German version of the Developmental Test of Visual Perception – Adolescent and Adult (DTVP-A). 11 % of the children with specific reading disorder show clinically relevant performance on the DTVP-A. The perceptual abilities of both groups differ significantly. No significant group differences exist after controlling for general IQ or Perceptional Reasoning Index, but they do remain after controlling for Verbal Comprehension, Working Memory, and Processing Speed Index. The number of children with reading difficulties suffering from visual perceptual disorders has been underestimated. For this reason, visual perceptual abilities should always be tested when making a reading disorder diagnosis. Profiles of IQ-test results of children suffering from reading and visual perceptual disorders should be interpreted carefully.

A zone-specific fish-based biotic index as a management tool for the Zeeschelde estuary (Belgium).

PubMed

Breine, Jan; Quataert, Paul; Stevens, Maarten; Ollevier, Frans; Volckaert, Filip A M; Van den Bergh, Ericia; Maes, Joachim

2010-07-01

Fish-based indices monitor changes in surface waters and are a valuable aid in communication by summarising complex information about the environment (Harrison and Whitfield, 2004). A zone-specific fish-based multimetric estuarine index of biotic integrity (Z-EBI) was developed based on a 13 year time series of fish surveys from the Zeeschelde estuary (Belgium). Sites were pre-classified using indicators of anthropogenic impact. Metrics showing a monotone response with pressure classes were selected for further analysis. Thresholds for the good ecological potential (GEP) were defined from references. A modified trisection was applied for the other thresholds. The Z-EBI is defined by the average of the metric scores calculated over a one year period and translated into an ecological quality ratio (EQR). The indices integrate structural and functional qualities of the estuarine fish communities. The Z-EBI performances were successfully validated for habitat degradation in the various habitat zones. Copyright 2010 Elsevier Ltd. All rights reserved.

Comparing the rankings obtained from two biodiversity indices: the Fair Proportion Index and the Shapley Value.

PubMed

Wicke, Kristina; Fischer, Mareike

2017-10-07

The Shapley Value and the Fair Proportion Index of phylogenetic trees have been frequently discussed as prioritization tools in conservation biology. Both indices rank species according to their contribution to total phylogenetic diversity, allowing for a simple conservation criterion. While both indices have their specific advantages and drawbacks, it has recently been shown that both values are closely related. However, as different authors use different definitions of the Shapley Value, the specific degree of relatedness depends on the specific version of the Shapley Value - it ranges from a high correlation index to equality of the indices. In this note, we first give an overview of the different indices. Then we turn our attention to the mere ranking order provided by either of the indices. We compare the rankings obtained from different versions of the Shapley Value for a phylogenetic tree of European amphibians and illustrate their differences. We then undertake further analyses on simulated data and show that even though the chance of two rankings being exactly identical (when obtained from different versions of the Shapley Value) decreases with an increasing number of taxa, the distance between the two rankings converges to zero, i.e., the rankings are becoming more and more alike. Moreover, we introduce our freely available software package FairShapley, which was implemented in Perl and with which all calculations have been performed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Early signs that predict later haemodynamically significant patent ductus arteriosus.

PubMed

Engür, Defne; Deveci, Murat; Türkmen, Münevver K

2016-03-01

Our aim was to determine the optimal cut-off values, sensitivity, specificity, and diagnostic power of 12 echocardiographic parameters on the second day of life to predict subsequent ductal patency. We evaluated preterm infants, born at ⩽32 weeks of gestation, starting on their second day of life, and they were evaluated every other day until ductal closure or until there were clinical signs of re-opening. We measured transductal diameter; pulmonary arterial diastolic flow; retrograde aortic diastolic flow; pulsatility index of the left pulmonary artery and descending aorta; left atrium and ventricle/aortic root ratio; left ventricular output; left ventricular flow velocity time integral; mitral early/late diastolic flow; and superior caval vein diameter and flow as well as performed receiver operating curve analysis. Transductal diameter (>1.5 mm); pulmonary arterial diastolic flow (>25.6 cm/second); presence of retrograde aortic diastolic flow; ductal diameter by body weight (>1.07 mm/kg); left pulmonary arterial pulsatility index (⩽0.71); and left ventricle to aortic root ratio (>2.2) displayed high sensitivity and specificity (p0.9). Parameters with moderate sensitivity and specificity were as follows: left atrial to aortic root ratio; left ventricular output; left ventricular flow velocity time integral; and mitral early/late diastolic flow ratio (p0.05) had low diagnostic value. Left pulmonary arterial pulsatility index, left ventricle/aortic root ratio, and ductal diameter by body weight are useful adjuncts offering a broader outlook for predicting ductal patency.

The receiver operational characteristic for binary classification with multiple indices and its application to the neuroimaging study of Alzheimer's disease.

PubMed

Wu, Xia; Li, Juan; Ayutyanont, Napatkamon; Protas, Hillary; Jagust, William; Fleisher, Adam; Reiman, Eric; Yao, Li; Chen, Kewei

2013-01-01

Given a single index, the receiver operational characteristic (ROC) curve analysis is routinely utilized for characterizing performances in distinguishing two conditions/groups in terms of sensitivity and specificity. Given the availability of multiple data sources (referred to as multi-indices), such as multimodal neuroimaging data sets, cognitive tests, and clinical ratings and genomic data in Alzheimer’s disease (AD) studies, the single-index-based ROC underutilizes all available information. For a long time, a number of algorithmic/analytic approaches combining multiple indices have been widely used to simultaneously incorporate multiple sources. In this study, we propose an alternative for combining multiple indices using logical operations, such as “AND,” “OR,” and “at least n” (where n is an integer), to construct multivariate ROC (multiV-ROC) and characterize the sensitivity and specificity statistically associated with the use of multiple indices. With and without the “leave-one-out” cross-validation, we used two data sets from AD studies to showcase the potentially increased sensitivity/specificity of the multiV-ROC in comparison to the single-index ROC and linear discriminant analysis (an analytic way of combining multi-indices). We conclude that, for the data sets we investigated, the proposed multiV-ROC approach is capable of providing a natural and practical alternative with improved classification accuracy as compared to univariate ROC and linear discriminant analysis.

The Receiver Operational Characteristic for Binary Classification with Multiple Indices and Its Application to the Neuroimaging Study of Alzheimer’s Disease

PubMed Central

Wu, Xia; Li, Juan; Ayutyanont, Napatkamon; Protas, Hillary; Jagust, William; Fleisher, Adam; Reiman, Eric; Yao, Li; Chen, Kewei

2014-01-01

Given a single index, the receiver operational characteristic (ROC) curve analysis is routinely utilized for characterizing performances in distinguishing two conditions/groups in terms of sensitivity and specificity. Given the availability of multiple data sources (referred to as multi-indices), such as multimodal neuroimaging data sets, cognitive tests, and clinical ratings and genomic data in Alzheimer’s disease (AD) studies, the single-index-based ROC underutilizes all available information. For a long time, a number of algorithmic/analytic approaches combining multiple indices have been widely used to simultaneously incorporate multiple sources. In this study, we propose an alternative for combining multiple indices using logical operations, such as “AND,” “OR,” and “at least n” (where n is an integer), to construct multivariate ROC (multiV-ROC) and characterize the sensitivity and specificity statistically associated with the use of multiple indices. With and without the “leave-one-out” cross-validation, we used two data sets from AD studies to showcase the potentially increased sensitivity/specificity of the multiV-ROC in comparison to the single-index ROC and linear discriminant analysis (an analytic way of combining multi-indices). We conclude that, for the data sets we investigated, the proposed multiV-ROC approach is capable of providing a natural and practical alternative with improved classification accuracy as compared to univariate ROC and linear discriminant analysis. PMID:23702553

Radiological Evaluation of Strategic Structures in Patients with Mild Cognitive Impairment and Early Alzheimer's Disease.

PubMed

Nesteruk, Tomasz; Nesteruk, Marta; Styczyńska, Maria; Barcikowska-Kotowicz, Maria; Walecki, Jerzy

2016-01-01

The aim of the study was to evaluate the diagnostic value of two measurement techniques in patients with cognitive impairment - automated volumetry of the hippocampus, entorhinal cortex, parahippocampal gyrus, posterior cingulate gyrus, cortex of the temporal lobes and corpus callosum, and fractional anisotropy (FA) index measurement of the corpus callosum using diffusion tensor imaging. A total number of 96 patients underwent magnetic resonance imaging study of the brain - 33 healthy controls (HC), 33 patients with diagnosed mild cognitive impairment (MCI) and 30 patients with Alzheimer's disease (AD) in early stage. The severity of the dementia was evaluated with neuropsychological test battery. The volumetric measurements were performed automatically using FreeSurfer imaging software. The measurements of FA index were performed manually using ROI (region of interest) tool. The volumetric measurement of the temporal lobe cortex had the highest correct classification rate (68.7%), whereas the lowest was achieved with FA index measurement of the corpus callosum (51%). The highest sensitivity and specificity in discriminating between the patients with MCI vs. early AD was achieved with the volumetric measurement of the corpus callosum - the values were 73% and 71%, respectively, and the correct classification rate was 72%. The highest sensitivity and specificity in discriminating between HC and the patients with early AD was achieved with the volumetric measurement of the entorhinal cortex - the values were 94% and 100%, respectively, and the correct classification rate was 97%. The highest sensitivity and specificity in discriminating between HC and the patients with MCI was achieved with the volumetric measurement of the temporal lobe cortex - the values were 90% and 93%, respectively, and the correct classification rate was 92%. The diagnostic value varied depending on the measurement technique. The volumetric measurement of the atrophy proved to be the best imaging biomarker, which allowed the distinction between the groups of patients. The volumetric assessment of the corpus callosum proved to be a useful tool in discriminating between the patients with MCI vs. early AD.

Power and sensitivity of alternative fit indices in tests of measurement invariance.

PubMed

Meade, Adam W; Johnson, Emily C; Braddy, Phillip W

2008-05-01

Confirmatory factor analytic tests of measurement invariance (MI) based on the chi-square statistic are known to be highly sensitive to sample size. For this reason, G. W. Cheung and R. B. Rensvold (2002) recommended using alternative fit indices (AFIs) in MI investigations. In this article, the authors investigated the performance of AFIs with simulated data known to not be invariant. The results indicate that AFIs are much less sensitive to sample size and are more sensitive to a lack of invariance than chi-square-based tests of MI. The authors suggest reporting differences in comparative fit index (CFI) and R. P. McDonald's (1989) noncentrality index (NCI) to evaluate whether MI exists. Although a general value of change in CFI (.002) seemed to perform well in the analyses, condition specific change in McDonald's NCI values exhibited better performance than a single change in McDonald's NCI value. Tables of these values are provided as are recommendations for best practices in MI testing. PsycINFO Database Record (c) 2008 APA, all rights reserved.

Responsiveness of pain and disability measures for chronic whiplash.

PubMed

Stewart, Mark; Maher, Christopher G; Refshauge, Kathryn M; Bogduk, Nikolai; Nicholas, Michael

2007-03-01

Cohort study. To evaluate the responsiveness of common pain and disability measures in a cohort of patients with chronic whiplash. Pain and disability are routinely measured in clinical practice and clinical research. However, to date, a head-to-head comparison of competing measures for whiplash patients has not been performed. Pain (pain intensity, bothersomeness, and SF-36 bodily pain score) and disability (Patient Specific Functional Scale, Neck Disability Index, Functional Rating Index, Copenhagen Scale, and SF-36 physical summary) measures were completed by 132 patients with chronic whiplash at baseline and then again after 6 weeks together with an 11-point global perceived effect scale. Internal responsiveness was evaluated by calculating effect sizes and standardized response means, and external responsiveness by correlating change scores with global perceived effect scores and by ROC curves. The ranking of responsiveness was consistent across the different analyses. Pain bothersomeness was more responsive than pain intensity, which was more responsive than the SF-36 pain measure. The Patient Specific Functional Scale was the most responsive disability measure, followed by the spine-specific measures, with the SF-36 physical summary measure the least responsive. Pain bothersomeness and the Patient Specific Functional Scale provide the most responsive measures of pain and disability, respectively, in patients with chronic whiplash.

Screening of Cognitive Impairment in Schizophrenia: Reliability, Sensitivity, and Specificity of the Repeatable Battery for the Assessment of Neuropsychological Status in a Spanish Sample.

PubMed

De la Torre, Gabriel G; Perez, Maria J; Ramallo, Miguel A; Randolph, Christopher; González-Villegas, Macarena Bernal

2016-04-01

In recent years, a number of studies focusing on the evaluation of neuropsychological deficits in individuals with schizophrenia have shown deficits that include several cognitive functions. Attention deficits as well as memory or executive function deficits are common in this kind of disorder together with sustained attention problems, working memory deficiencies, and problem-solving difficulties, among many others. Currently, the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is gaining special importance in the evaluation of the cognitive deficits associated with schizophrenia. In this article, we describe an RBANS screening in a sample of 88 Spanish patients diagnosed with schizophrenia. We also aimed to check the battery's reliability, sensitivity, and specificity in the studied sample. We performed a comparative study with 88 healthy participants. The results showed a reliability index value of α = .795 and an item value of α = .762. For total test reliability, we obtained an index value of α = .761 and an item value of α = .762. Sensitivity score was 87.5% and specificity 86.4%. RBANS obtained good reliability, sensitivity, and specificity scores and represents a good screening tool in detecting cognitive deficits associated with schizophrenia. © The Author(s) 2015.

Qualitative and quantitative analysis of specific polysaccharides in Dendrobium huoshanense by using saccharide mapping and chromatographic methods.

PubMed

Deng, Yong; Chen, Ling-Xiao; Han, Bang-Xing; Wu, Ding-Tao; Cheong, Kit-Leong; Chen, Nai-Fu; Zhao, Jing; Li, Shao-Ping

2016-09-10

Qualitative and quantitative analysis of specific polysaccharides from ten batches of Dendrobium huoshanense were performed using high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector (HPSEC-MALLS-RID), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR) and saccharide mapping based on polysaccharides analysis by using carbohydrate gel electrophoresis (PACE) and high performance thin layer chromatography (HPTLC). Results showed that molecular weights, the radius of gyrations, and contents of specific polysaccharides in D. huoshanense were ranging from 1.16×10(5) to 2.17×10(5)Da, 38.8 to 52.1nm, and 9.9% to 19.9%, respectively. Furthermore, the main monosaccharide compositions were Man and Glc. Indeed, the main glycosidic linkages were β-1,4-Manp and β-1,4-Glcp, and substituted with acetyl groups at O-2 and O-3 of 1,4-linked Manp. Moreover, results showed that PACE and HPTLC fingerprints of partial acidic and enzymatic hydrolysates of specific polysaccharides were similar, which are helpful to better understand the specific polysaccharides in D. huoshanense and beneficial to improve their quality control. These approaches could also be routinely used for quality control of polysaccharides in other medicinal plants. Copyright © 2016 Elsevier B.V. All rights reserved.

Change deafness, dual-task performance, and domain-specific expertise.

PubMed

Neuhoff, John G; Bochtler, Katharina S

2018-05-01

In a change deafness manipulation using radio broadcasts of sporting events, we show that change deafness to a switch in talker increases when listeners are asked to monitor both lexical and indexical information for change. We held semantic content constant and demonstrated a change deafness rate of 85% when participants listened to the home team broadcast of a hockey game that switched midway to the away team broadcast with a different announcer. In Study 2, participants were asked to monitor either the indexical characteristics ( listen for a change in announcer) or both the indexical and semantic components ( listen for a change in announcer or a goal scored). Monitoring both components led to significantly greater change deafness even though both groups were alerted to the possibility of a change in announcer. In Study 3, we changed both the indexical and the semantic components when the broadcast switched from a hockey game to a basketball game. We found a negative correlation between sports expertise and change deafness. The results are discussed in terms of the nature of perceptual representation and the influence of expertise and evolution on attention allocation.

Measurement of health system performance at district level: A study protocol

PubMed Central

Sharma, Atul; Prinja, Shankar; Aggarwal, Arun Kumar

2018-01-01

Background Limited efforts have been observed in low and middle income countries to undertake health system performance assessment at district level. Absence of a comprehensive data collection tool and lack of a standardised single summary measure defining overall performance are some of the main problems. Present study has been undertaken to develop a summary composite health system performance index at district level. Methods A broad range of indicators covering all six domains as per building block framework were finalized by an expert panel. The domains were classified into twenty sub-domains, with 70 input and process indicators to measure performance. Seven sub-domains for assessing health system outputs and outcomes were identified, with a total of 28 indicators. Districts in Haryana state from north India were selected for the study. Primary and secondary data will be collected from 378 health facilities, district and state health directorate headquarters. Indicators will be normalized, aggregated to generate composite performance index at district level. Domain specific scores will present the quality of individual building block domains in the public health system. Robustness of the results will be checked using sensitivity analysis. Expected impact for public health: The study presents a methodology for comprehensive assessment of all health system domains on basis of input, process, output and outcome indicators which has never been reported from India. Generation of this index will help identify policy and implementation areas of concern and point towards potential solutions. Results may also help understand relationships between individual building blocks and their sub-components. Significance for public health Measuring performance of health system is important to understand progress and challenges, and create systems that are efficient, equitable and patient-focused. However, very few assessments of such nature have been observed in low and middle income countries, especially at district level, mainly because of methodological challenges. This study presents a methodology for comprehensive assessment of all domains of health system and generation of a composite Health System Performance Index on the basis of input, process, output and outcome indicators. It will help identify policy and implementation problems worthy of attention and point towards potential solutions to health system bottlenecks resulting in poor performance. The results may also help better understand the relationships between individual building blocks and their sub-components and the overall performance of the health system. PMID:29441330

Early seizure detection in an animal model of temporal lobe epilepsy

NASA Astrophysics Data System (ADS)

Talathi, Sachin S.; Hwang, Dong-Uk; Ditto, William; Carney, Paul R.

2007-11-01

The performance of five seizure detection schemes, i.e., Nonlinear embedding delay, Hurst scaling, Wavelet Scale, autocorrelation and gradient of accumulated energy, in their ability to detect EEG seizures close to the seizure onset time were evaluated to determine the feasibility of their application in the development of a real time closed loop seizure intervention program (RCLSIP). The criteria chosen for the performance evaluation were, high statistical robustness as determined through the predictability index, the sensitivity and the specificity of a given measure to detect an EEG seizure, the lag in seizure detection with respect to the EEG seizure onset time, as determined through visual inspection and the computational efficiency for each detection measure. An optimality function was designed to evaluate the overall performance of each measure dependent on the criteria chosen. While each of the above measures analyzed for seizure detection performed very well in terms of the statistical parameters, the nonlinear embedding delay measure was found to have the highest optimality index due to its ability to detect seizure very close to the EEG seizure onset time, thereby making it the most suitable dynamical measure in the development of RCLSIP in rat model with chronic limbic epilepsy.

On the performance evaluation of LQAM-MPPM techniques over exponentiated Weibull fading free-space optical channels

NASA Astrophysics Data System (ADS)

Khallaf, Haitham S.; Elfiqi, Abdulaziz E.; Shalaby, Hossam M. H.; Sampei, Seiichi; Obayya, Salah S. A.

2018-06-01

We investigate the performance of hybrid L-ary quadrature-amplitude modulation-multi-pulse pulse-position modulation (LQAM-MPPM) techniques over exponentiated Weibull (EW) fading free-space optical (FSO) channel, considering both weather and pointing-error effects. Upper bound and approximate-tight upper bound expressions for the bit-error rate (BER) of LQAM-MPPM techniques over EW FSO channels are obtained, taking into account the effects of fog, beam divergence, and pointing-error. Setup block diagram for both the transmitter and receiver of the LQAM-MPPM/FSO system are introduced and illustrated. The BER expressions are evaluated numerically and the results reveal that LQAM-MPPM technique outperforms ordinary LQAM and MPPM schemes under different fading levels and weather conditions. Furthermore, the effect of modulation-index is investigated and it turned out that a modulation-index greater than 0.4 is required in order to optimize the system performance. Finally, the effect of pointing-error introduces a great power penalty on the LQAM-MPPM system performance. Specifically, at a BER of 10-9, pointing-error introduces power penalties of about 45 and 28 dB for receiver aperture sizes of DR = 50 and 200 mm, respectively.

Prosthetic Hand Technology-Phase II

DTIC Science & Technology

2013-02-01

Corporation; model number HV 1100. The motor location of the ring finger was identified and chosen for the experiments. The EMG detection system...model parameters for the experiments, where the subject performed a random series of flexion’s of the ring finger. Figure 1.6 shows the output of the...obtained from specific Motor Unit locations corresponding to the index, middle and ring finger, and the corresponding force data is presented. This is a

Publications of the Jet Propulsion Laboratory, 1988

NASA Technical Reports Server (NTRS)

1989-01-01

This bibliography describes and indexes by primary author the externally distributed technical reporting, released during calendar year 1988, that resulted from scientific and engineering work performed, or managed, by the Jet Propulsion Laboratory. Three classes of publications are included: JPL publications in which the information is complete for a specific accomplishment; articles from the quarterly Telecommunications and Data Acquisition (TDA) Progress Report; and articles published in the open literature.

Publications of the Jet Propulsion Laboratory, 1985

NASA Technical Reports Server (NTRS)

1986-01-01

This bibliography describes and indexes by primary author the externally distributed technical reporting, released during calender year 1985, that resulted from scientific and engineering work performed, or managed, by the Jet Propulsion Laboratory. Three classes of publications are included: JPL publications in which the information is complete for a specific accomplisment; Articles from the quarterly Telecommunications and Data Acquisition (TDA) Progress Report; and article published in the open literature.

Automated Psychological Categorization via Linguistic Processing System

DTIC Science & Technology

2004-09-01

try to break the groups down by variables such as: age, gender, income, ethnicity, nationality, religion , martial status, and size of household...Collective orientation gains self-esteem from a specific group (family, ethnic group, religion , etc.) and is motivated to perform consistent with the... Pseudoscience ’, Skeptical Enquirer 19(4): 19-25 (1995). Pratkanis, Anthony, R. (in press). Social Influence Analysis: An Index of Tactics. In A. R. Pratkanis

Dysfunctional error-related processing in female psychopathy

PubMed Central

Steele, Vaughn R.; Edwards, Bethany G.; Bernat, Edward M.; Calhoun, Vince D.; Kiehl, Kent A.

2016-01-01

Neurocognitive studies of psychopathy have predominantly focused on male samples. Studies have shown that female psychopaths exhibit similar affective deficits as their male counterparts, but results are less consistent across cognitive domains including response modulation. As such, there may be potential gender differences in error-related processing in psychopathic personality. Here we investigate response-locked event-related potential (ERP) components [the error-related negativity (ERN/Ne) related to early error-detection processes and the error-related positivity (Pe) involved in later post-error processing] in a sample of incarcerated adult female offenders (n = 121) who performed a response inhibition Go/NoGo task. Psychopathy was assessed using the Hare Psychopathy Checklist-Revised (PCL-R). The ERN/Ne and Pe were analyzed with classic windowed ERP components and principal component analysis (PCA). Consistent with previous research performed in psychopathic males, female psychopaths exhibited specific deficiencies in the neural correlates of post-error processing (as indexed by reduced Pe amplitude) but not in error monitoring (as indexed by intact ERN/Ne amplitude). Specifically, psychopathic traits reflecting interpersonal and affective dysfunction remained significant predictors of both time-domain and PCA measures reflecting reduced Pe mean amplitude. This is the first evidence to suggest that incarcerated female psychopaths exhibit similar dysfunctional post-error processing as male psychopaths. PMID:26060326

Comparison of equi-minimum alveolar concentration of sevoflurane and isoflurane on bispectral index values during both wash in and wash out phases: A prospective randomised study

PubMed Central

Gupta, Madhu; Shri, Iti; Sakia, Prashant; Govil, Deepika

2015-01-01

Background and Aims: At equal minimum alveolar concentration (MAC), volatile agents may produce different bispectral index (BIS) values especially at low BIS levels when the effect is volatile agent specific. The present study was performed to compare the BIS values produced by sevoflurane and isoflurane at equal MAC and thereby assessing which is a better hypnotic agent. Methods: Sixty American Society of Anaesthesiologists I and II patients undergoing elective mastoidectomy were divided into groups receiving either isoflurane or sevoflurane, and at equi-MAC. BIS value was measured during both wash in and wash out phase, keeping other parameters same. Statistical analysis was performed using the Friedman two-way analysis and Mann-Whitney U-test. A P < 0.05 was considered significant. Results: BIS value was significantly lower with sevoflurane at all MAC values as compared to isoflurane, except in the beginning and at MAC awake. However, both the drugs proved to be cardiostable. Conclusion: At equi-MAC sevoflurane produces lower BIS values during wash in as well as wash out phase as compared to isoflurane, reflecting probably an agent specific effect and a deficiency in BIS algorithm for certain agents and their interplay. PMID:25788739

British isles lupus assessment group 2004 index is valid for assessment of disease activity in systemic lupus erythematosus

PubMed Central

Yee, Chee-Seng; Farewell, Vernon; Isenberg, David A; Rahman, Anisur; Teh, Lee-Suan; Griffiths, Bridget; Bruce, Ian N; Ahmad, Yasmeen; Prabu, Athiveeraramapandian; Akil, Mohammed; McHugh, Neil; D'Cruz, David; Khamashta, Munther A; Maddison, Peter; Gordon, Caroline

2007-01-01

Objective To determine the construct and criterion validity of the British Isles Lupus Assessment Group 2004 (BILAG-2004) index for assessing disease activity in systemic lupus erythematosus (SLE). Methods Patients with SLE were recruited into a multicenter cross-sectional study. Data on SLE disease activity (scores on the BILAG-2004 index, Classic BILAG index, and Systemic Lupus Erythematosus Disease Activity Index 2000 [SLEDAI-2K]), investigations, and therapy were collected. Overall BILAG-2004 and overall Classic BILAG scores were determined by the highest score achieved in any of the individual systems in the respective index. Erythrocyte sedimentation rates (ESRs), C3 levels, C4 levels, anti–double-stranded DNA (anti-dsDNA) levels, and SLEDAI-2K scores were used in the analysis of construct validity, and increase in therapy was used as the criterion for active disease in the analysis of criterion validity. Statistical analyses were performed using ordinal logistic regression for construct validity and logistic regression for criterion validity. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Results Of the 369 patients with SLE, 92.7% were women, 59.9% were white, 18.4% were Afro-Caribbean and 18.4% were South Asian. Their mean ± SD age was 41.6 ± 13.2 years and mean disease duration was 8.8 ± 7.7 years. More than 1 assessment was obtained on 88.6% of the patients, and a total of 1,510 assessments were obtained. Increasing overall scores on the BILAG-2004 index were associated with increasing ESRs, decreasing C3 levels, decreasing C4 levels, elevated anti-dsDNA levels, and increasing SLEDAI-2K scores (all P < 0.01). Increase in therapy was observed more frequently in patients with overall BILAG-2004 scores reflecting higher disease activity. Scores indicating active disease (overall BILAG-2004 scores of A and B) were significantly associated with increase in therapy (odds ratio [OR] 19.3, P < 0.01). The BILAG-2004 and Classic BILAG indices had comparable sensitivity, specificity, PPV, and NPV. Conclusion These findings show that the BILAG-2004 index has construct and criterion validity. PMID:18050213

Psychometric properties of the Fibromyalgia Assessment Status (FAS) index: a national web-based study of fibromyalgia.

PubMed

Iannuccelli, C; Sarzi-Puttini, P; Atzeni, F; Cazzola, M; di Franco, M; Guzzo, M P; Bazzichi, L; Cassisi, G A; Marsico, A; Stisi, S; Salaffi, F

2011-01-01

Fibromyalgia (FM) is a generalized chronic pain condition that is often accompanied by symptoms such as fatigue, sleep disturbances, psychological and cognitive alterations, headache, migraine, variable bowel habits, diffuse abdominal pain, and urinary frequency. Its key assessment domains include pain, fatigue, disturbed sleep, physical and emotional functioning, and patient global satisfaction and health-related quality of life (HRQL). A number of evaluation measures have been adapted from the fields of rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis, and others such as the Fibromyalgia Assessment Status (FAS) index and the Fibromyalgia Impact Questionnaire (FIQ) have been specifically developed. The aim of this study was to assess the impact of FM on HRQL by comparing the performance of the FAS index, the FIQ and the Health Assessment Questionnaire [HAQ] in 541 female and 31 male FM patients (mean age 50 years; mean disease duration 7.7 years) entered in the database of a web-based survey registry developed by the Italian Fibromyalgia Network (IFINET). Tests of convergent validity showed that the FAS index and FIQ significantly correlated with each other (rho=0.608, p<0.0001), but there were also significant correlations between the FAS index and other clinical measures of disability, including the HAQ (rho=0.423, p<0.0001), anxiety (rho=0.138, p=0.0009), depression (rho=0.174, p<0.0001) and, especially, the number of comorbidities (rho=0.147, p=0.0004). The FAS index revealed a statistically significant difference between males and females (p=0.048), analysed using the Mann-Whitney U-test for all pair wise comparisons. The FAS index is a valid three-item instrument (pain, fatigue and sleep disturbances) that performs at least as well as the FIQ in FM patients, and is simpler to administer and score. Both questionnaires may be useful when screening FM patients, with the choice of the most appropriate instrument depending on the setting.

Treatment option of bendamustine in combination with rituximab in elderly and frail patients with aggressive B-non-Hodgkin lymphoma: rational, efficacy, and tolerance.

PubMed

Horn, Julia; Kleber, Martina; Hieke, Stefanie; Schmitt-Gräff, Annette; Wäsch, Ralph; Engelhardt, Monika

2012-10-01

We analyzed the safety and efficacy of rituximab plus bendamustine (R-B) in elderly and frail patients with aggressive B-non-Hodgkin lymphoma (a-B-NHL). Few reports have as yet reported on R-B in a-B-NHL, albeit its value for indolent lymphoma vs. R-CHOP has impressively been shown. We assessed 20 consecutive patients with a-B-NHL receiving R-B as first-line or relapse treatment after (R)-CHOP in our department. Besides patient- and lymphoma-specific characteristics, comorbidity indices were determined. The median patient age was 72 years (51-86), the median Karnofsky performance status was 55 % (40-90 %), and according to the international prognostic index, 15 had high-intermediate or high-risk disease. The comorbidity indices revealed a median Kaplan-Feinstein index of 3 (range 1-3), Charlson comorbidity index of 4 (range 0-9), hematopoietic cell transplantation-specific comorbidity index of 3 (range 0-11), and Freiburg comorbidity index of 2 (range 0-2). Moreover, eight patients had echocardiographic and laboratory signs of cardiac insufficiency, all leading to R-B rather than R-CHOP treatment. The overall response rate was 55 %, with complete response and partial response rates of 20 and 35 %, respectively. In our frail and elderly patient cohort, R-B therapy was well-tolerated. Median progression free survival and overall survival were 8.3 months (95 % confidence interval [CI], 2.8--not reached [n.r.]) and 19.4 months (95 % CI, 4.6--n.r.), respectively. We conclude that R-B is a feasible and safe therapy option in a-B-NHL patients not qualifying for R-CHOP but needs to be further assessed in larger subsequent trials, these currently being under way.

Novel Radiobiological Gamma Index for Evaluation of 3-Dimensional Predicted Dose Distribution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sumida, Iori, E-mail: sumida@radonc.med.osaka-u.ac.jp; Yamaguchi, Hajime; Kizaki, Hisao

2015-07-15

Purpose: To propose a gamma index-based dose evaluation index that integrates the radiobiological parameters of tumor control (TCP) and normal tissue complication probabilities (NTCP). Methods and Materials: Fifteen prostate and head and neck (H&N) cancer patients received intensity modulated radiation therapy. Before treatment, patient-specific quality assurance was conducted via beam-by-beam analysis, and beam-specific dose error distributions were generated. The predicted 3-dimensional (3D) dose distribution was calculated by back-projection of relative dose error distribution per beam. A 3D gamma analysis of different organs (prostate: clinical [CTV] and planned target volumes [PTV], rectum, bladder, femoral heads; H&N: gross tumor volume [GTV], CTV,more » spinal cord, brain stem, both parotids) was performed using predicted and planned dose distributions under 2%/2 mm tolerance and physical gamma passing rate was calculated. TCP and NTCP values were calculated for voxels with physical gamma indices (PGI) >1. We propose a new radiobiological gamma index (RGI) to quantify the radiobiological effects of TCP and NTCP and calculate radiobiological gamma passing rates. Results: The mean RGI gamma passing rates for prostate cases were significantly different compared with those of PGI (P<.03–.001). The mean RGI gamma passing rates for H&N cases (except for GTV) were significantly different compared with those of PGI (P<.001). Differences in gamma passing rates between PGI and RGI were due to dose differences between the planned and predicted dose distributions. Radiobiological gamma distribution was visualized to identify areas where the dose was radiobiologically important. Conclusions: RGI was proposed to integrate radiobiological effects into PGI. This index would assist physicians and medical physicists not only in physical evaluations of treatment delivery accuracy, but also in clinical evaluations of predicted dose distribution.« less

Validation of an osteoporosis self-assessment tool to identify primary osteoporosis and new osteoporotic vertebral fractures in postmenopausal Chinese women in Beijing

PubMed Central

2013-01-01

Background This study aimed to validate the effectiveness of the Osteoporosis Self-assessment Tool for Asians (OSTA) in identifying postmenopausal women at increased risk of primary osteoporosis and painful new osteoporotic vertebral fractures in a large selected Han Chinese population in Beijing. Methods We assessed the performance of the OSTA in 1201 women. Subjects with an OSTA index > -1 were classified as the low risk group, and those with an index ≤ -1 were classified as the increased risk group. Osteoporosis is defined by a T-score ≤ 2.5 standard deviations according to the WHO criteria. All painful, new vertebral fractures were identified by X-ray and MRI scans with correlating clinical signs and symptoms. We determined the sensitivity, specificity, and area under the receiver operating characteristic (ROC) curve for correctly selecting women with osteoporosis and painful new vertebral fractures. Results Of the study subjects, 29.3% had osteoporosis, and the prevalence of osteoporosis increased progressively with age. The areas under the ROC curves of the OSTA index (cutoff = -1) to identify osteoporosis in the femoral neck, total hip, and lumbar spine were 0.824, 0.824, and 0.776, respectively. The sensitivity and specificity of the OSTA index (cutoff = -1) to identify osteoporosis in healthy women were 66% and 76%, respectively. With regard to painful new vertebral fractures, the area under the ROC curve relating the OSTA index (cutoff = -1) to new vertebral fractures was 0.812. Conclusions The OSTA may be a simple and effective tool for identifying the risk of osteoporosis and new painful osteoporotic vertebral fractures in Han Chinese women. PMID:24053509

Homogeneous and inhomogeneous material effect in gamma index evaluation of IMRT technique based on fan beam and Cone Beam CT patient images

NASA Astrophysics Data System (ADS)

Wibowo, W. E.; Waliyyulhaq, M.; Pawiro, S. A.

2017-05-01

Patient-specific Quality Assurance (QA) technique in lung case Intensity-Modulated Radiation Therapy (IMRT) is traditionally limited to homogeneous material, although the fact that the planning is carried out with inhomogeneous material present. Moreover, the chest area has many of inhomogeneous material, such as lung, soft tissue, and bone, which inhomogeneous material requires special attention to avoid inaccuracies in dose calculation in the Treatment Planning System (TPS). Recent preliminary studies shown that the role of Cone Beam CT (CBCT) can be used not only to position the patient at the time prior to irradiation but also to serve as planning modality. Our study presented the influence of a homogeneous and inhomogeneous materials using Fan Beam CT and Cone Beam CT modalities in IMRT technique on the Gamma Index (GI) value. We used a variation of the segment and Calculation Grid Resolution (CGR). The results showed the deviation of averaged GI value to be between CGR 0.2 cm and 0.4 cm with homogeneous material ranging from -0.44% to 1.46%. For inhomogeneous material, the value was range from -1.74% to 0.98%. In performing patient-specific IMRT QA techniques for lung cancer, homogeneous material can be implemented in evaluating the gamma index.

[The specific features of Doppler ultrasound study of ophthalmic vessels in young persons with peripheral vitreochorioretinal dystrophies].

PubMed

Pozdeeva, O G

2005-01-01

Hemodynamic parameters were studied in the ophthalmic artery, short posterior ciliary arteries (SPCA), long posterior ciliary arteries (LPCA), and central artery of the retina (CAR). Doppler ultrasound study (DUSS) was performed on an Acuson Aspen multipurpose diagnostic system using a linear transducer at a frequency of 7.5 MHz in the pulse mode. Chelyabinsk students aged 17-25 years were examined. A number of specific features of retinal blood supply were detected in young persons with dystrophic diseases of the periphery of the fundus oculi. These included decreased blood flow velocities and less systolic flow acceleration time in SPCA, LPCA, and CAR in peripheral vitreochorioretinal dystrophies (PVCRD). The higher pulsatile index (PI) in the LPCA system characterized a possible mechanism responsible for compensation of impaired blood supply in the retinal periphery in the development of PVCRD. The high values of the pulsatile index and the vascular wall resistivity index in CAR reflected the changes determining the absence of complications as retinal ruptures and detachment. There were neither changes in ophthalmic arterial blood flow depending on the type of PVCRD and the nature of its course nor significant differences in blood supply to the eye in different types of refraction.

Managing in-hospital quality improvement: An importance-performance analysis to set priorities for ST-elevation myocardial infarction care.

PubMed

Aeyels, Daan; Seys, Deborah; Sinnaeve, Peter R; Claeys, Marc J; Gevaert, Sofie; Schoors, Danny; Sermeus, Walter; Panella, Massimiliano; Bruyneel, Luk; Vanhaecht, Kris

2018-02-01

A focus on specific priorities increases the success rate of quality improvement efforts for broad and complex-care processes. Importance-performance analysis presents a possible approach to set priorities around which to design and implement effective quality improvement initiatives. Persistent variation in hospital performance makes ST-elevation myocardial infarction care relevant to consider for importance-performance analysis. The purpose of this study was to identify quality improvement priorities in ST-elevation myocardial infarction care. Importance and performance levels of ST-elevation myocardial infarction key interventions were combined in an importance-performance analysis. Content validity indexes on 23 ST-elevation myocardial infarction key interventions of a multidisciplinary RAND Delphi Survey defined importance levels. Structured review of 300 patient records in 15 acute hospitals determined performance levels. The significance of between-hospital variation was determined by a Kruskal-Wallis test. A performance heat-map allowed for hospital-specific priority setting. Seven key interventions were each rated as an overall improvement priority. Priority key interventions related to risk assessment, timely reperfusion by percutaneous coronary intervention and secondary prevention. Between-hospital performance varied significantly for the majority of key interventions. The type and number of priorities varied strongly across hospitals. Guideline adherence in ST-elevation myocardial infarction care is low and improvement priorities vary between hospitals. Importance-performance analysis helps clinicians and management in demarcation of the nature, number and order of improvement priorities. By offering a tailored improvement focus, this methodology makes improvement efforts more specific and achievable.

Breast cancer Ki67 expression preoperative discrimination by DCE-MRI radiomics features

NASA Astrophysics Data System (ADS)

Ma, Wenjuan; Ji, Yu; Qin, Zhuanping; Guo, Xinpeng; Jian, Xiqi; Liu, Peifang

2018-02-01

To investigate whether quantitative radiomics features extracted from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) are associated with Ki67 expression of breast cancer. In this institutional review board approved retrospective study, we collected 377 cases Chinese women who were diagnosed with invasive breast cancer in 2015. This cohort included 53 low-Ki67 expression (Ki67 proliferation index less than 14%) and 324 cases with high-Ki67 expression (Ki67 proliferation index more than 14%). A binary-classification of low- vs. high- Ki67 expression was performed. A set of 52 quantitative radiomics features, including morphological, gray scale statistic, and texture features, were extracted from the segmented lesion area. Three most common machine learning classification methods, including Naive Bayes, k-Nearest Neighbor and support vector machine with Gaussian kernel, were employed for the classification and the least absolute shrink age and selection operator (LASSO) method was used to select most predictive features set for the classifiers. Classification performance was evaluated by the area under receiver operating characteristic curve (AUC), accuracy, sensitivity and specificity. The model that used Naive Bayes classification method achieved the best performance than the other two methods, yielding 0.773 AUC value, 0.757 accuracy, 0.777 sensitivity and 0.769 specificity. Our study showed that quantitative radiomics imaging features of breast tumor extracted from DCE-MRI are associated with breast cancer Ki67 expression. Future larger studies are needed in order to further evaluate the findings.

Shift Work and Cognitive Flexibility: Decomposing Task Performance.

PubMed

Cheng, Philip; Tallent, Gabriel; Bender, Thomas John; Tran, Kieulinh Michelle; Drake, Christopher L

2017-04-01

Deficits in cognitive functioning associated with shift work are particularly relevant to occupational performance; however, few studies have examined how cognitive functioning is associated with specific components of shift work. This observational study examined how circadian phase, nocturnal sleepiness, and daytime insomnia in a sample of shift workers ( N = 30) were associated with cognitive flexibility during the night shift. Cognitive flexibility was measured using a computerized task-switching paradigm, which produces 2 indexes of flexibility: switch cost and set inhibition. Switch cost represents the additional cognitive effort required in switching to a different task and can impact performance when multitasking is involved. Set inhibition is the efficiency in returning to previously completed tasks and represents the degree of cognitive perseveration, which can lead to reduced accuracy. Circadian phase was measured via melatonin assays, nocturnal sleepiness was assessed using the Multiple Sleep Latency Test, and daytime insomnia was assessed using the Insomnia Severity Index. Results indicated that those with an earlier circadian phase, insomnia, and sleepiness exhibited reduced cognitive flexibility; however, specific components of cognitive flexibility were differentially associated with circadian phase, insomnia, and sleepiness. Individuals with an earlier circadian phase (thus more misaligned to the night shift) exhibited larger switch costs, which was also associated with reduced task efficiency. Shift workers with more daytime insomnia demonstrated difficulties with cognitive inhibition, whereas nocturnal sleepiness was associated with difficulties in reactivating previous tasks. Deficits in set inhibition were also related to reduced accuracy and increased perseverative errors. Together, this study indicates that task performance deficits in shift work are complex and are variably impacted by different mechanisms. Future research may examine phenotypic differences in shift work and the associated consequences. Results also suggest that fatigue risk management strategies may benefit from increased scope and specificity in assessment of sleep, sleepiness, and circadian rhythms in shift workers.

Efficacy of functional movement screening for predicting injuries in coast guard cadets.

PubMed

Knapik, Joseph J; Cosio-Lima, Ludimila M; Reynolds, Katy L; Shumway, Richard S

2015-05-01

Functional movement screening (FMS) examines the ability of individuals to perform highly specific movements with the aim of identifying individuals who have functional limitations or asymmetries. It is assumed that individuals who can more effectively accomplish the required movements have a lower injury risk. This study determined the ability of FMS to predict injuries in the United States Coast Guard (USCG) cadets. Seven hundred seventy male and 275 female USCG freshman cadets were administered the 7 FMS tests before the physically intense 8-week Summer Warfare Annual Basic (SWAB) training. Physical training-related injuries were recorded during SWAB training. Cumulative injury incidence was calculated at various FMS cutpoint scores. The ability of the FMS total score to predict injuries was examined by calculating sensitivity and specificity. Determination of the FMS cutpoint that maximized specificity and sensitivity was determined from the Youden's index (sensitivity + specificity - 1). For men, FMS scores ≤ 12 were associated with higher injury risk than scores >12; for women, FMS scores ≤ 15 were associated with higher injury risk than scores >15. The Youden's Index indicated that the optimal FMS cutpoint was ≤ 11 for men (22% sensitivity, 87% specificity) and ≤ 14 for women (60% sensitivity, 61% specificity). Functional movement screening demonstrated moderate prognostic accuracy for determining injury risk among female Coast Guard cadets but relatively low accuracy among male cadets. Attempting to predict injury risk based on the FMS test seems to have some limited promise based on the present and past investigations.

A Study of the Efficiency of Spatial Indexing Methods Applied to Large Astronomical Databases

NASA Astrophysics Data System (ADS)

Donaldson, Tom; Berriman, G. Bruce; Good, John; Shiao, Bernie

2018-01-01

Spatial indexing of astronomical databases generally uses quadrature methods, which partition the sky into cells used to create an index (usually a B-tree) written as database column. We report the results of a study to compare the performance of two common indexing methods, HTM and HEALPix, on Solaris and Windows database servers installed with a PostgreSQL database, and a Windows Server installed with MS SQL Server. The indexing was applied to the 2MASS All-Sky Catalog and to the Hubble Source catalog. On each server, the study compared indexing performance by submitting 1 million queries at each index level with random sky positions and random cone search radius, which was computed on a logarithmic scale between 1 arcsec and 1 degree, and measuring the time to complete the query and write the output. These simulated queries, intended to model realistic use patterns, were run in a uniform way on many combinations of indexing method and indexing level. The query times in all simulations are strongly I/O-bound and are linear with number of records returned for large numbers of sources. There are, however, considerable differences between simulations, which reveal that hardware I/O throughput is a more important factor in managing the performance of a DBMS than the choice of indexing scheme. The choice of index itself is relatively unimportant: for comparable index levels, the performance is consistent within the scatter of the timings. At small index levels (large cells; e.g. level 4; cell size 3.7 deg), there is large scatter in the timings because of wide variations in the number of sources found in the cells. At larger index levels, performance improves and scatter decreases, but the improvement at level 8 (14 min) and higher is masked to some extent in the timing scatter caused by the range of query sizes. At very high levels (20; 0.0004 arsec), the granularity of the cells becomes so high that a large number of extraneous empty cells begin to degrade performance. Thus, for the use patterns studied here the database performance is not critically dependent on the exact choices of index or level.

Analytical and simulator study of advanced transport

NASA Technical Reports Server (NTRS)

Levison, W. H.; Rickard, W. W.

1982-01-01

An analytic methodology, based on the optimal-control pilot model, was demonstrated for assessing longitidunal-axis handling qualities of transport aircraft in final approach. Calibration of the methodology is largely in terms of closed-loop performance requirements, rather than specific vehicle response characteristics, and is based on a combination of published criteria, pilot preferences, physical limitations, and engineering judgment. Six longitudinal-axis approach configurations were studied covering a range of handling qualities problems, including the presence of flexible aircraft modes. The analytical procedure was used to obtain predictions of Cooper-Harper ratings, a solar quadratic performance index, and rms excursions of important system variables.

The influence of clutter on real-world scene search: evidence from search efficiency and eye movements.

PubMed

Henderson, John M; Chanceaux, Myriam; Smith, Tim J

2009-01-23

We investigated the relationship between visual clutter and visual search in real-world scenes. Specifically, we investigated whether visual clutter, indexed by feature congestion, sub-band entropy, and edge density, correlates with search performance as assessed both by traditional behavioral measures (response time and error rate) and by eye movements. Our results demonstrate that clutter is related to search performance. These results hold for both traditional search measures and for eye movements. The results suggest that clutter may serve as an image-based proxy for search set size in real-world scenes.

Comparison of the performance of the CMS Hierarchical Condition Category (CMS-HCC) risk adjuster with the Charlson and Elixhauser comorbidity measures in predicting mortality.

PubMed

Li, Pengxiang; Kim, Michelle M; Doshi, Jalpa A

2010-08-20

The Centers for Medicare and Medicaid Services (CMS) has implemented the CMS-Hierarchical Condition Category (CMS-HCC) model to risk adjust Medicare capitation payments. This study intends to assess the performance of the CMS-HCC risk adjustment method and to compare it to the Charlson and Elixhauser comorbidity measures in predicting in-hospital and six-month mortality in Medicare beneficiaries. The study used the 2005-2006 Chronic Condition Data Warehouse (CCW) 5% Medicare files. The primary study sample included all community-dwelling fee-for-service Medicare beneficiaries with a hospital admission between January 1st, 2006 and June 30th, 2006. Additionally, four disease-specific samples consisting of subgroups of patients with principal diagnoses of congestive heart failure (CHF), stroke, diabetes mellitus (DM), and acute myocardial infarction (AMI) were also selected. Four analytic files were generated for each sample by extracting inpatient and/or outpatient claims for each patient. Logistic regressions were used to compare the methods. Model performance was assessed using the c-statistic, the Akaike's information criterion (AIC), the Bayesian information criterion (BIC) and their 95% confidence intervals estimated using bootstrapping. The CMS-HCC had statistically significant higher c-statistic and lower AIC and BIC values than the Charlson and Elixhauser methods in predicting in-hospital and six-month mortality across all samples in analytic files that included claims from the index hospitalization. Exclusion of claims for the index hospitalization generally led to drops in model performance across all methods with the highest drops for the CMS-HCC method. However, the CMS-HCC still performed as well or better than the other two methods. The CMS-HCC method demonstrated better performance relative to the Charlson and Elixhauser methods in predicting in-hospital and six-month mortality. The CMS-HCC model is preferred over the Charlson and Elixhauser methods if information about the patient's diagnoses prior to the index hospitalization is available and used to code the risk adjusters. However, caution should be exercised in studies evaluating inpatient processes of care and where data on pre-index admission diagnoses are unavailable.

Self-rated job performance and absenteeism according to employee engagement, health behaviors, and physical health.

PubMed

Merrill, Ray M; Aldana, Steven G; Pope, James E; Anderson, David R; Coberley, Carter R; Grossmeier, Jessica J; Whitmer, R William

2013-01-01

To better understand the combined influence of employee engagement, health behavior, and physical health on job performance and absenteeism. Analyses were based on 20,114 employees who completed the Healthways Well-Being Assessment from 2008 to 2010. Employees represented three geographically dispersed companies in the United States. Employee engagement, health behavior, and physical health indices were simultaneously significantly associated with job performance and also with absenteeism. Employee engagement had a greater association with job performance than did the health behavior or physical health indices, whereas the physical health index was more strongly associated with absenteeism. Specific elements of the indices were evaluated for association with self-rated job performance and absenteeism. Efforts to improve worker productivity should take a holistic approach encompassing employee health improvement and engagement strategies.

Achieving Deeper Energy Savings in Federal Energy Performance Contracts

DOE PAGES

Shonder, John A.; Nasseri, Cyrus

2015-01-01

Legislation requires each agency of the US federal government to reduce the aggregate energy use index of its buildings by 30% by 2015, with respect to a 2003 baseline. The declining availability of appropriated funding means that energy performance contracting will be key to achieving this goal. Historically however, energy performance contracts have been able to reduce energy use by only about 20% over baseline. Achieving 30% energy reductions using performance contracting will require new approaches and a specific focus on achieving higher energy savings, both by ESCOs and by agencies. This paper describes some of the ways federal agenciesmore » are meeting this challenge, and presents results from the efforts of one agency the US General Services Administration -- to achieve deeper energy savings in conventional energy savings performance contracts.« less

Design and fabrication of a miniature objective consisting of high refractive index zinc sulfide lenses for laser surgery

PubMed Central

Shadfan, Adam; Pawlowski, Michal; Wang, Ye; Subramanian, Kaushik; Gabay, Ilan; Ben-Yakar, Adela; Tkaczyk, Tomasz

2016-01-01

A miniature laser ablation probe relying on an optical fiber to deliver light requires a high coupling efficiency objective with sufficient magnification in order to provide adequate power and field for surgery. A diffraction-limited optical design is presented that utilizes high refractive index zinc sulfide to meet specifications while reducing the miniature objective down to two lenses. The design has a hypercentric conjugate plane on the fiber side and is telecentric on the tissue end. Two versions of the objective were built on a diamond lathe—a traditional cylindrical design and a custom-tapered mount. Both received an antireflective coating. The objectives performed as designed in terms of observable resolution and field of view as measured by imaging a 1951 USAF resolution target. The slanted edge technique was used to find Strehl ratios of 0.75 and 0.78, respectively, indicating nearly diffraction-limited performance. Finally, preliminary ablation experiments indicated threshold fluence of gold film was comparable to similar reported probes. PMID:28579656

Design and fabrication of a miniature objective consisting of high refractive index zinc sulfide lenses for laser surgery

NASA Astrophysics Data System (ADS)

Shadfan, Adam; Pawlowski, Michal; Wang, Ye; Subramanian, Kaushik; Gabay, Ilan; Ben-Yakar, Adela; Tkaczyk, Tomasz

2016-02-01

A miniature laser ablation probe relying on an optical fiber to deliver light requires a high coupling efficiency objective with sufficient magnification in order to provide adequate power and field for surgery. A diffraction-limited optical design is presented that utilizes high refractive index zinc sulfide to meet specifications while reducing the miniature objective down to two lenses. The design has a hypercentric conjugate plane on the fiber side and is telecentric on the tissue end. Two versions of the objective were built on a diamond lathe-a traditional cylindrical design and a custom-tapered mount. Both received an antireflective coating. The objectives performed as designed in terms of observable resolution and field of view as measured by imaging a 1951 USAF resolution target. The slanted edge technique was used to find Strehl ratios of 0.75 and 0.78, respectively, indicating nearly diffraction-limited performance. Finally, preliminary ablation experiments indicated threshold fluence of gold film was comparable to similar reported probes.

The English and Chinese versions of the five-level EuroQoL Group's five-dimension questionnaire (EQ-5D) were valid and reliable and provided comparable scores in Asian breast cancer patients.

PubMed

Lee, Chun Fan; Ng, Raymond; Luo, Nan; Wong, Nan Soon; Yap, Yoon Sim; Lo, Soo Kien; Chia, Whay Kuang; Yee, Alethea; Krishna, Lalit; Wong, Celest; Goh, Cynthia; Cheung, Yin Bun

2013-01-01

To examine the measurement properties of and comparability between the English and Chinese versions of the five-level EuroQoL Group's five-dimension questionnaire (EQ-5D) in breast cancer patients in Singapore. This is an observational study of 269 patients. Known-group validity and responsiveness of the EQ-5D utility index and visual analog scale (VAS) were assessed in relation to various clinical characteristics and longitudinal change in performance status, respectively. Convergent and divergent validity was examined by correlation coefficients between the EQ-5D and a breast cancer-specific instrument. Test-retest reliability was evaluated. The two language versions were compared by multiple regression analyses. For both English and Chinese versions, the EQ-5D utility index and VAS demonstrated known-group validity and convergent and divergent validity, and presented sufficient test-retest reliability (intraclass correlation = 0.72 to 0.83). The English version was responsive to changes in performance status. The Chinese version was responsive to decline in performance status, but there was no conclusive evidence about its responsiveness to improvement in performance status. In the comparison analyses of the utility index and VAS between the two language versions, borderline results were obtained, and equivalence cannot be definitely confirmed. The five-level EQ-5D is valid, responsive, and reliable in assessing health outcome of breast cancer patients. The English and Chinese versions provide comparable measurement results.

Use of a Tracing Task to Assess Visuomotor Performance: Effects of Age, Sex, and Handedness

PubMed Central

2013-01-01

Background. Visuomotor abnormalities are common in aging and age-related disease, yet difficult to quantify. This study investigated the effects of healthy aging, sex, and handedness on the performance of a tracing task. Participants (n = 150, aged 21–95 years, 75 females) used a stylus to follow a moving target around a circle on a tablet computer with their dominant and nondominant hands. Participants also performed the Trail Making Test (a measure of executive function). Methods. Deviations from the circular path were computed to derive an “error” time series. For each time series, absolute mean, variance, and complexity index (a proposed measure of system functionality and adaptability) were calculated. Using the moving target and stylus coordinates, the percentage of task time within the target region and the cumulative micropause duration (a measure of motion continuity) were computed. Results. All measures showed significant effects of aging (p < .0005). Post hoc age group comparisons showed that with increasing age, the absolute mean and variance of the error increased, complexity index decreased, percentage of time within the target region decreased, and cumulative micropause duration increased. Only complexity index showed a significant difference between dominant versus nondominant hands within each age group (p < .0005). All measures showed relationships to the Trail Making Test (p < .05). Conclusions. Measures derived from a tracing task identified performance differences in healthy individuals as a function of age, sex, and handedness. Studies in populations with specific neuromotor syndromes are warranted to test the utility of measures based on the dynamics of tracking a target as a clinical assessment tool. PMID:23388876

Standard & Poor's "Return on Resources" Measure of School Performance. Issue Brief. Volume 1, Issue 1

ERIC Educational Resources Information Center

Reeder, Brian

2004-01-01

Standard & Poors (S&P) uses a measure they call a Performance Cost Index (PCI) as their measure of a school or district?s ?Return on Resources?. The Performance Cost Index is defined as the average cost per measured ?unit? of student performance. In its simplest form, the Performance Cost Index is calculated as per student expenditures divided by…

Non-invasive assessment of peripheral arterial disease: Automated ankle brachial index measurement and pulse volume analysis compared to duplex scan.

PubMed

Lewis, Jane Ea; Williams, Paul; Davies, Jane H

2016-01-01

This cross-sectional study aimed to individually and cumulatively compare sensitivity and specificity of the (1) ankle brachial index and (2) pulse volume waveform analysis recorded by the same automated device, with the presence or absence of peripheral arterial disease being verified by ultrasound duplex scan. Patients (n=205) referred for lower limb arterial assessment underwent ankle brachial index measurement and pulse volume waveform recording using volume plethysmography, followed by ultrasound duplex scan. The presence of peripheral arterial disease was recorded if ankle brachial index <0.9; pulse volume waveform was graded as 2, 3 or 4; or if haemodynamically significant stenosis >50% was evident with ultrasound duplex scan. Outcome measure was agreement between the measured ankle brachial index and interpretation of pulse volume waveform for peripheral arterial disease diagnosis, using ultrasound duplex scan as the reference standard. Sensitivity of ankle brachial index was 79%, specificity 91% and overall accuracy 88%. Pulse volume waveform sensitivity was 97%, specificity 81% and overall accuracy 85%. The combined sensitivity of ankle brachial index and pulse volume waveform was 100%, specificity 76% and overall accuracy 85%. Combining these two diagnostic modalities within one device provided a highly accurate method of ruling out peripheral arterial disease, which could be utilised in primary care to safely reduce unnecessary secondary care referrals.

Development of a prognostic nomogram for cirrhotic patients with upper gastrointestinal bleeding.

PubMed

Zhou, Yu-Jie; Zheng, Ji-Na; Zhou, Yi-Fan; Han, Yi-Jing; Zou, Tian-Tian; Liu, Wen-Yue; Braddock, Martin; Shi, Ke-Qing; Wang, Xiao-Dong; Zheng, Ming-Hua

2017-10-01

Upper gastrointestinal bleeding (UGIB) is a complication with a high mortality rate in critically ill patients presenting with cirrhosis. Today, there exist few accurate scoring models specifically designed for mortality risk assessment in critically ill cirrhotic patients with upper gastrointestinal bleeding (CICGIB). Our aim was to develop and evaluate a novel nomogram-based model specific for CICGIB. Overall, 540 consecutive CICGIB patients were enrolled. On the basis of Cox regression analyses, the nomogram was constructed to estimate the probability of 30-day, 90-day, 270-day, and 1-year survival. An upper gastrointestinal bleeding-chronic liver failure-sequential organ failure assessment (UGIB-CLIF-SOFA) score was derived from the nomogram. Performance assessment and internal validation of the model were performed using Harrell's concordance index (C-index), calibration plot, and bootstrap sample procedures. UGIB-CLIF-SOFA was also compared with other prognostic models, such as CLIF-SOFA and model for end-stage liver disease, using C-indices. Eight independent factors derived from Cox analysis (including bilirubin, creatinine, international normalized ratio, sodium, albumin, mean artery pressure, vasopressin used, and hematocrit decrease>10%) were assembled into the nomogram and the UGIB-CLIF-SOFA score. The calibration plots showed optimal agreement between nomogram prediction and actual observation. The C-index of the nomogram using bootstrap (0.729; 95% confidence interval: 0.689-0.766) was higher than that of the other models for predicting survival of CICGIB. We have developed and internally validated a novel nomogram and an easy-to-use scoring system that accurately predicts the mortality probability of CICGIB on the basis of eight easy-to-obtain parameters. External validation is now warranted in future clinical studies.

Method for selection of optimal road safety composite index with examples from DEA and TOPSIS method.

PubMed

Rosić, Miroslav; Pešić, Dalibor; Kukić, Dragoslav; Antić, Boris; Božović, Milan

2017-01-01

Concept of composite road safety index is a popular and relatively new concept among road safety experts around the world. As there is a constant need for comparison among different units (countries, municipalities, roads, etc.) there is need to choose an adequate method which will make comparison fair to all compared units. Usually comparisons using one specific indicator (parameter which describes safety or unsafety) can end up with totally different ranking of compared units which is quite complicated for decision maker to determine "real best performers". Need for composite road safety index is becoming dominant since road safety presents a complex system where more and more indicators are constantly being developed to describe it. Among wide variety of models and developed composite indexes, a decision maker can come to even bigger dilemma than choosing one adequate risk measure. As DEA and TOPSIS are well-known mathematical models and have recently been increasingly used for risk evaluation in road safety, we used efficiencies (composite indexes) obtained by different models, based on DEA and TOPSIS, to present PROMETHEE-RS model for selection of optimal method for composite index. Method for selection of optimal composite index is based on three parameters (average correlation, average rank variation and average cluster variation) inserted into a PROMETHEE MCDM method in order to choose the optimal one. The model is tested by comparing 27 police departments in Serbia. Copyright © 2016 Elsevier Ltd. All rights reserved.

A ranking index for quality assessment of forensic DNA profiles forensic DNA profiles

PubMed Central

2010-01-01

Background Assessment of DNA profile quality is vital in forensic DNA analysis, both in order to determine the evidentiary value of DNA results and to compare the performance of different DNA analysis protocols. Generally the quality assessment is performed through manual examination of the DNA profiles based on empirical knowledge, or by comparing the intensities (allelic peak heights) of the capillary electrophoresis electropherograms. Results We recently developed a ranking index for unbiased and quantitative quality assessment of forensic DNA profiles, the forensic DNA profile index (FI) (Hedman et al. Improved forensic DNA analysis through the use of alternative DNA polymerases and statistical modeling of DNA profiles, Biotechniques 47 (2009) 951-958). FI uses electropherogram data to combine the intensities of the allelic peaks with the balances within and between loci, using Principal Components Analysis. Here we present the construction of FI. We explain the mathematical and statistical methodologies used and present details about the applied data reduction method. Thereby we show how to adapt the ranking index for any Short Tandem Repeat-based forensic DNA typing system through validation against a manual grading scale and calibration against a specific set of DNA profiles. Conclusions The developed tool provides unbiased quality assessment of forensic DNA profiles. It can be applied for any DNA profiling system based on Short Tandem Repeat markers. Apart from crime related DNA analysis, FI can therefore be used as a quality tool in paternal or familial testing as well as in disaster victim identification. PMID:21062433

An examination of the Wechsler Adult Intelligence Scales, Fourth Edition (WAIS-IV) in individuals with complicated mild, moderate and Severe traumatic brain injury (TBI).

PubMed

Carlozzi, Noelle E; Kirsch, Ned L; Kisala, Pamela A; Tulsky, David S

2015-01-01

This study examined the clinical utility of the Wechsler Adult Intelligence Scales-Fourth Edition (WAIS-IV) in individuals with complicated mild, moderate or severe TBI. One hundred individuals with TBI (n = 35 complicated mild or moderate TBI; n = 65 severe TBI) and 100 control participants matched on key demographic variables from the WAIS-IV normative dataset completed the WAIS-IV. Univariate analyses indicated that participants with severe TBI had poorer performance than matched controls on all index scores and subtests (except Matrix Reasoning). Individuals with complicated mild/moderate TBI performed more poorly than controls on the Working Memory Index (WMI), Processing Speed Index (PSI), and Full Scale IQ (FSIQ), and on four subtests: the two processing speed subtests (SS, CD), two working memory subtests (AR, LN), and a perceptual reasoning subtest (BD). Participants with severe TBI had significantly lower scores than the complicated mild/moderate TBI on PSI, and on three subtests: the two processing speed subtests (SS and CD), and the new visual puzzles test. Effect sizes for index and subtest scores were generally small-to-moderate for the group with complicated mild/moderate and moderate-to-large for the group with severe TBI. PSI also showed good sensitivity and specificity for classifying individuals with severe TBI versus controls. Findings provide support for the clinical utility of the WAIS-IV in individuals with complicated mild, moderate, and severe TBI.

PCOGR: phylogenetic COG ranking as an online tool to judge the specificity of COGs with respect to freely definable groups of organisms.

PubMed

Meereis, Florian; Kaufmann, Michael

2004-10-15

The rapidly increasing number of completely sequenced genomes led to the establishment of the COG-database which, based on sequence homologies, assigns similar proteins from different organisms to clusters of orthologous groups (COGs). There are several bioinformatic studies that made use of this database to determine (hyper)thermophile-specific proteins by searching for COGs containing (almost) exclusively proteins from (hyper)thermophilic genomes. However, public software to perform individually definable group-specific searches is not available. The tool described here exactly fills this gap. The software is accessible at http://www.uni-wh.de/pcogr and is linked to the COG-database. The user can freely define two groups of organisms by selecting for each of the (current) 66 organisms to belong either to groupA, to the reference groupB or to be ignored by the algorithm. Then, for all COGs a specificity index is calculated with respect to the specificity to groupA, i. e. high scoring COGs contain proteins from the most of groupA organisms while proteins from the most organisms assigned to groupB are absent. In addition to ranking all COGs according to the user defined specificity criteria, a graphical visualization shows the distribution of all COGs by displaying their abundance as a function of their specificity indexes. This software allows detecting COGs specific to a predefined group of organisms. All COGs are ranked in the order of their specificity and a graphical visualization allows recognizing (i) the presence and abundance of such COGs and (ii) the phylogenetic relationship between groupA- and groupB-organisms. The software also allows detecting putative protein-protein interactions, novel enzymes involved in only partially known biochemical pathways, and alternate enzymes originated by convergent evolution.

Neuroimaging of Brain Injuries and Disorders at Cleveland Clinic

DTIC Science & Technology

2013-12-01

LFBFs) in the human brain during a state of alert rest. These spontaneous fluctuations are correlated in brain regions with a high degree of connectivity...behavioral performance on the finger tapping fMRI scan. One subject was excluded due to significantly different anatomy from the group (large ventricles...FSL 4.0 image processing software package (http://www.fmrib.ox.ac.uk/fsl/tbss/index.html) to create a mean white matter skeleton . Specifically, all

Publications of the Jet Propulsion Laboratory 1987

NASA Technical Reports Server (NTRS)

1988-01-01

A bibliography is presented which describes and indexes by author the externally distributed technical reporting, released during the calender year 1987, that resulted from scientific and engineering work performed, or managed, by the Jet Propulsion Lab. Three classes of publications are included: (1) JPL publications in which the information is complete for a specific accomplishment; (2) Articles from the quarterly Telecommunications and Data Acquisition Progress Report; and (3) Articles published in the open literature.

An Analytical Index to the Internet: Dreams of Utopia.

ERIC Educational Resources Information Center

Casey, Carol

1999-01-01

Explores the need for analytical indexes to access Internet resources. Considers bibliographic control, Web site design, keyword search engines, hierarchical subject indexes, and special indexes and compilations of links, and concludes that the creation of small, focused indexes may be the best solution for accessing specific types of digital…

Complexity in Indexing Systems--Abandonment and Failure: Implications for Organizing the Internet.

ERIC Educational Resources Information Center

Weinberg, Bella Hass

1996-01-01

Discusses detailed classification systems, sophisticated alphabetical indexing systems and reasons for the abandonment of complex indexing systems. The suggested structure for indexing the Internet or other large electronic collections of documents is based on that of book indexes: specific headings with coined modifications. (Author/AEF)

A Stream Multimetric Macroinvertebrate Index (MMI) for the Sand Hills Ecoregion of the Southeastern Plains, USA

NASA Astrophysics Data System (ADS)

Kosnicki, Ely; Sefick, Stephen A.; Paller, Michael H.; Jerrell, Miller S.; Prusha, Blair A.; Sterrett, Sean C.; Tuberville, Tracey D.; Feminella, Jack W.

2016-10-01

A macroinvertebrate multimetric index is an effective tool for assessing the biological integrity of streams. However, data collected under a single protocol may not be available for an entire region. We sampled macroinvertebrates from the full extent of the Sand Hills ecoregion Level IV of the Southeastern Plains with a standard protocol during the summers of 2010-2012. We evaluated the performance of 94 metrics through a series of screening criteria and built 48 macroinvertebrate multimetric indexs with combinations of the best performing metrics, representing richness, habit, functional feeding guild, sensitivity, and community composition. A series of narrative-response tests for each macroinvertebrate multimetric index was used to find the best performing macroinvertebrate multimetric index which we called the Sand Hills macroinvertebrate multimetric index. The Sand Hills macroinvertebrate multimetric index consisted of the measures Biotic Index, % Shredder taxa, Clinger taxa2/total taxa, Plecoptera and Trichoptera richness, and Tanytarsini taxa2/Chironomidae taxa. Comparison of the Sand Hills macroinvertebrate multimetric index with existing assessment tools calculated with our data indicated that the Sand Hills macroinvertebrate multimetric index performs at a high level with regard to identifying degraded sites and in its response to stress gradients.

Collapse of optical wave arrested by cross-phase modulation in nonlinear metamaterials

NASA Astrophysics Data System (ADS)

Zhang, Jinggui; Li, Ying; Xiang, Yuanjiang; Lei, Dajun; Zhang, Lifu

2016-03-01

In this article, we put forward a novel strategy to realize the management of wave collapse through designing probe-pump configuration where probe wave is assumed to propagate in the positive-index region of metamaterials (MMs), while pump wave is assumed to propagate in the negative-index region. We disclose that cross-phase modulation (XPM) in MMs as a new physical mechanism that can be used to arrest the collapse of probe wave in the positive-index region by copropagating it together with pump wave in the negative-index region. Further, we observe that pump wave will evolve into a ring while probe wave will develop a side lob in the wings during the course of coupled waves propagation, different from the corresponding counterpart in the ordinary positive-index materials (OMs) where they simultaneously exhibit the catastrophic self-focusing behavior. Meanwhile, we also discuss how to control the collapse of probe wave by adjusting intensity-detuned pump wave. Our analysis is performed by directly numerically solving the coupled nonlinear Schrödinger equations, as well as using the variational approximation, both showing consistent results. The finding demonstrates XPM as a specific physical mechanism in MMs can provide us unique opportunities unattainable in OMs to manipulate self-focusing of high-power laser.

Diagnostic accuracy of tests to detect Hepatitis C antibody: a meta-analysis and review of the literature.

PubMed

Tang, Weiming; Chen, Wen; Amini, Ali; Boeras, Debi; Falconer, Jane; Kelly, Helen; Peeling, Rosanna; Varsaneux, Olivia; Tucker, Joseph D; Easterbrook, Philippa

2017-11-01

Although direct-acting antivirals can achieve sustained virological response rates greater than 90% in Hepatitis C Virus (HCV) infected persons, at present the majority of HCV-infected individuals remain undiagnosed and therefore untreated. While there are a wide range of HCV serological tests available, there is a lack of formal assessment of their diagnostic performance. We undertook a systematic review and meta-analysis to evaluate he diagnostic accuracy of available rapid diagnostic tests (RDT) and laboratory based EIA assays in detecting antibodies to HCV. We used the PRISMA checklist and Cochrane guidance to develop our search protocol. The search strategy was registered in PROSPERO (CRD42015023567). The search focused on hepatitis C, diagnostic tests, and diagnostic accuracy within eight databases (MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Conference Proceedings Citation Index-Science, SCOPUS, Literatura Latino-Americana e do Caribe em Ciências da Saúde and WHO Global Index Medicus. Studies were included if they evaluated an assay to determine the sensitivity and specificity of HCV antibody (HCV Ab) in humans. Two reviewers independently extracted data and performed a quality assessment of the studies using the QUADAS tool. We pooled test estimates using the DerSimonian-Laird method, by using the software R and RevMan. 5.3. A total of 52 studies were identified that included 52,673 unique test measurements. Based on five studies, the pooled sensitivity and specificity of HCV Ab rapid diagnostic tests (RDTs) were 98% (95% CI 98-100%) and 100% (95% CI 100-100%) compared to an enzyme immunoassay (EIA) reference standard. High HCV Ab RDTs sensitivity and specificity were observed across screening populations (general population, high risk populations, and hospital patients) using different reference standards (EIA, nucleic acid testing, immunoblot). There were insufficient studies to undertake subanalyses based on HIV co-infection. Oral HCV Ab RDTs also had excellent sensitivity and specificity compared to blood reference tests, respectively at 94% (95% CI 93-96%) and 100% (95% CI 100-100%). Among studies that assessed individual oral RDTs, the eight studies revealed that OraQuick ADVANCE® had a slightly higher sensitivity (98%, 95% CI 97-98%) compared to the other oral brands (pooled sensitivity: 88%, 95% CI 84-92%). RDTs, including oral tests, have excellent sensitivity and specificity compared to laboratory-based methods for HCV antibody detection across a wide range of settings. Oral HCV Ab RDTs had good sensitivity and specificity compared to blood reference standards.

Tree cover and species composition effects on academic performance of primary school students.

PubMed

Sivarajah, Sivajanani; Smith, Sandy M; Thomas, Sean C

2018-01-01

Human exposure to green space and vegetation is widely recognized to result in physical and mental health benefits; however, to date, the specific effects of tree cover, diversity, and species composition on student academic performance have not been investigated. We compiled standardized performance scores in Grades 3 and 6 for the collective student body in 387 schools across the Toronto District School Board (TDSB), and examined variation in relation to tree cover, tree diversity, and tree species composition based on comprehensive inventories of trees on school properties combined with aerial-photo-based assessments of tree cover. Analyses accounted for variation due to socioeconomic factors using the learning opportunity index (LOI), a regional composite index of external challenges to learning that incorporates income and other factors, such as students with English as a second language. As expected, LOI had the greatest influence on student academic performance; however, the proportion of tree cover, as distinct from other types of "green space" such as grass, was found to be a significant positive predictor of student performance, accounting for 13% of the variance explained in a statistical model predicting mean student performance assessments. The effects of tree cover and species composition were most pronounced in schools that showed the highest level of external challenges, suggesting the importance of urban forestry investments in these schools.

Tree cover and species composition effects on academic performance of primary school students

PubMed Central

Smith, Sandy M.; Thomas, Sean C.

2018-01-01

Human exposure to green space and vegetation is widely recognized to result in physical and mental health benefits; however, to date, the specific effects of tree cover, diversity, and species composition on student academic performance have not been investigated. We compiled standardized performance scores in Grades 3 and 6 for the collective student body in 387 schools across the Toronto District School Board (TDSB), and examined variation in relation to tree cover, tree diversity, and tree species composition based on comprehensive inventories of trees on school properties combined with aerial-photo-based assessments of tree cover. Analyses accounted for variation due to socioeconomic factors using the learning opportunity index (LOI), a regional composite index of external challenges to learning that incorporates income and other factors, such as students with English as a second language. As expected, LOI had the greatest influence on student academic performance; however, the proportion of tree cover, as distinct from other types of “green space” such as grass, was found to be a significant positive predictor of student performance, accounting for 13% of the variance explained in a statistical model predicting mean student performance assessments. The effects of tree cover and species composition were most pronounced in schools that showed the highest level of external challenges, suggesting the importance of urban forestry investments in these schools. PMID:29474503

[Definition and specification requirements for PAC-systems (picture archiving and communication system). A performance index with reference to the standard "IEEE Recommended Practice for Software Requirement Specifications"].

PubMed

König, H; Klose, K J

1999-04-01

The formulation of requirements is necessary to control the goals of a PACS project. Furthermore, in this way, the scope of functionality necessary to support radiological working processes becomes clear. Definitions of requirements and specification are formulated independently of systems according to the IEEE standard "Recommended Practice for Software Requirements Specifications". Definitions are given in the Request for Information, specifications in the Request for Proposal. Functional and non-functional requirements are distinguished. The solutions are rated with respect to scope, appropriateness and quality of implementation. A PACS checklist was created according to the methods described above. It is published on the homepage of the "Arbeitsgemeinschaft Informationstechnologie" (AGIT) within the "Deutsche Röntgengesellschaft" (DRG) (http://www.uni-marburg.de/mzr/agit). The checklist provides a discussion forum which should contribute to an agreement on accepted basic PACS functionalities.

Early Detection of Progressive Adolescent Idiopathic Scoliosis: A Severity Index.

PubMed

Skalli, Wafa; Vergari, Claudio; Ebermeyer, Eric; Courtois, Isabelle; Drevelle, Xavier; Kohler, Remi; Abelin-Genevois, Kariman; Dubousset, Jean

2017-06-01

Early detection of progressive adolescent idiopathic scoliosis (AIS) was assessed based on 3D quantification of the deformity. Based on 3D quantitative description of scoliosis curves, the aim is to assess a specific phenotype that could be an early detectable severity index for progressive AIS. Early detection of progressive scoliosis is important for adapted treatment to limit progression. However, progression risk assessment is mainly based on the follow up, waiting for signs of rapid progression that generally occur during the growth peak. Sixty-five mild scoliosis (16 boys, 49 girls, Cobb Angle between 10 and 20°) with a Risser between 0 and 2 were followed from their first examination until a decision was made by the clinician, either considering the spine as stable at the end of growth (26 patients) or planning to brace because of progression (39 patients). Calibrated biplanar x-rays were performed and 3D reconstructions of the spine allowed calculating six local parameters related to main curve deformity. For progressive curve 3D phenotype assessment, data were compared with those previously assessed for 30 severe scoliosis (Cobb Angle > 35°), 17 scoliosis before brace (Cobb Angle > 29°) and 53 spines of nonscoliosis subjects. A predictive discriminant analysis was performed to assess similarity of mild scoliosis curves either to those of scoliosis or nonscoliosis spines, yielding a severity index (S-index). S-index value at first examination was compared with clinical outcome. At the first exam, 53 out of 65 predictions (82%) were in agreement with actual clinical outcome. Approximately, 89% of the curves that were predicted as progressive proved accurate. Although still requiring large scale validation, results are promising for early detection of progressive curves. 2.

Sarcopenia and its individual criteria are associated, in part, with mortality among patients on hemodialysis.

PubMed

Kittiskulnam, Piyawan; Chertow, Glenn M; Carrero, Juan J; Delgado, Cynthia; Kaysen, George A; Johansen, Kirsten L

2017-07-01

The relative importance of sarcopenia and its individual components as independent predictors of mortality in the dialysis population has not been determined. We estimated whole-body muscle mass using pre-dialysis bioimpedance spectroscopy measurements in 645 ACTIVE/ADIPOSE-enrolled prevalent hemodialysis patients from San Francisco and Atlanta. Low muscle mass was defined as two standard deviations below sex-specific means for young adults from NHANES and indexed to height 2 , body weight, body surface area, or body mass index. We evaluated the association of sarcopenia (low muscle mass) by four indexing methods, weak hand grip strength, and slow gait speed with mortality. Seventy-eight deaths were observed during a mean follow-up of 1.9 years. Sarcopenia was not significantly associated with mortality after adjusting for covariates. No muscle mass criteria were associated with death, regardless of indexing metrics. In contrast, having weak grip strength or slow walking speed was associated with mortality in the adjusted model. Only gait slowness significantly improved the predictive accuracy for death with an increase in C-statistic from 0.63 to 0.68. However, both gait slowness and hand grip weakness significantly improved the net reclassification index compared to models without performance measures (50.5% for slowness and 33.7% for weakness), whereas models with muscle size did not. Neither sarcopenia nor low muscle mass by itself was a better predictor of mortality than functional limitation alone in patients receiving hemodialysis. Thus, physical performance measures, including slow gait speed and weak hand grip strength, were associated with mortality even after adjustment for muscle size and other confounders. Published by Elsevier Inc.

High Center Volume Does Not Mitigate Risk Associated with Using High Donor Risk Organs in Liver Transplantation.

PubMed

Beal, Eliza W; Black, Sylvester M; Mumtaz, Khalid; Hayes, Don; El-Hinnawi, Ashraf; Washburn, Kenneth; Tumin, Dmitry

2017-09-01

High-risk donor allografts increase access to liver transplant, but potentially reduce patient and graft survival. It is unclear whether the risk associated with using marginal donor livers is mitigated by increasing center experience. The United Network for Organ Sharing registry was queried for adult first-time liver transplant recipients between 2/2002 and 12/2015. High donor risk was defined as donor risk index >1.9, and 1-year patient and graft survival were compared according to donor risk index in small and large centers. Multivariable Cox regression estimated the hazard ratio (HR) associated with using high-risk donor organs, according to a continuous measure of annual center volume. The analysis included 51,770 patients. In 67 small and 67 large centers, high donor risk index predicted increased mortality (p = 0.001). In multivariable analysis, high-donor risk index allografts predicted greater mortality hazard at centers performing 20 liver transplants per year (HR 1.35; 95% CI 1.22, 1.49; p < 0.001) and, similarly, at centers performing 70 per year (HR 1.35; 95% CI 1.26, 1.43; p < 0.001). The interaction between high donor risk index and center volume was not statistically significant (p = 0.747), confirming that the risk associated with using marginal donor livers was comparable between smaller and larger centers. Results were consistent when examining graft loss. At both small and large centers, high-risk donor allografts were associated with reduced patient and graft survival after liver transplant. Specific strategies to mitigate the risk of liver transplant involving high-risk donors are needed, in addition to accumulation of center expertise.

Planning Ahead by Thinking Backwards.

ERIC Educational Resources Information Center

Farmer, Lesley S. J.

1996-01-01

Suggests evaluation criteria for selecting CD-ROMs and describes some typical titles along with examples of learning activities. Highlights include reference titles, including encyclopedias, magazine indexes, newspaper databases, subject-specific indexes, timetables and almanacs, and atlases; and curriculum-specific titles. (LRW)

Changes in optical properties of electroporated cells as revealed by digital holographic microscopy

PubMed Central

Calin, Violeta L.; Mihailescu, Mona; Mihale, Nicolae; Baluta, Alexandra V.; Kovacs, Eugenia; Savopol, Tudor; Moisescu, Mihaela G.

2017-01-01

Changes in optical and shape-related characteristics of B16F10 cells after electroporation were investigated using digital holographic microscopy (DHM). Bipolar rectangular pulses specific for electrochemotherapy were used. Electroporation was performed in an “off-axis” DHM set-up without using exogenous markers. Two types of cell parameters were monitored seconds and minutes after pulse train application: parameters addressing a specifically defined area of the cell (refractive index and cell height) and global cell parameters (projected area, optical phase shift profile and dry mass). The biphasic behavior of cellular parameters was explained by water and mannitol dynamics through the electropermeabilized cell membrane. PMID:28736667

Body mass index influences prostate cancer risk at biopsy in Japanese men.

PubMed

Masuda, Hitoshi; Kagawa, Makoto; Kawakami, Satoru; Numao, Noboru; Matsuoka, Yoh; Yokoyama, Minato; Yamamoto, Shinya; Yonese, Junji; Fukui, Iwao; Kihara, Kazunori

2013-07-01

To determine the relationship between body mass index and prostate cancer risk at biopsy in Japanese men, and to compared the risk with that of Caucasian men. We retrospectively evaluated 3966 men with prostate-specific antigen levels from 2.5 to 19.9 ng/mL who underwent an initial extended prostate biopsy. Using logistic regression, odds ratios of each body mass index category for risk of prostate cancer and high-grade disease (Gleason score ≥4 + 3) were estimated after controlling for age, prostate-specific antigen, %free prostate-specific antigen, prostate volume, digital rectal examination findings, family history of prostate cancer and the number of biopsy cores. Patients were divided into six categories according to their body mass index (kg/m(2) ) as follows: <21.0, 21.0-22.9, 23.0-24.9, 25.0-26.9, 27.0-29.9 and ≥30.0. A significant positive association was observed between body mass index and prostate cancer risk at biopsy, with an increased risk observed in men whose body mass index was ≥27.0 compared with the reference group. A significantly increased risk starting at body mass index ≥25.0 was found in high-grade disease. In contrast to our results, there has been no reported increase in the risk of prostate cancer at biopsy in Caucasians within the overweight range (body mass index of 25.0-29.9 based on World Health Organization classification). Japanese men within the overweight body mass index range who have an elevated prostate-specific antigen level also have a significant risk of harboring prostate cancer, especially high-grade disease. Overweight Japanese might be at greater prostate cancer risk at biopsy than overweight Caucasians. © 2012 The Japanese Urological Association.

Classification of malignant and benign lung nodules using taxonomic diversity index and phylogenetic distance.

PubMed

de Sousa Costa, Robherson Wector; da Silva, Giovanni Lucca França; de Carvalho Filho, Antonio Oseas; Silva, Aristófanes Corrêa; de Paiva, Anselmo Cardoso; Gattass, Marcelo

2018-05-23

Lung cancer presents the highest cause of death among patients around the world, in addition of being one of the smallest survival rates after diagnosis. Therefore, this study proposes a methodology for diagnosis of lung nodules in benign and malignant tumors based on image processing and pattern recognition techniques. Mean phylogenetic distance (MPD) and taxonomic diversity index (Δ) were used as texture descriptors. Finally, the genetic algorithm in conjunction with the support vector machine were applied to select the best training model. The proposed methodology was tested on computed tomography (CT) images from the Lung Image Database Consortium and Image Database Resource Initiative (LIDC-IDRI), with the best sensitivity of 93.42%, specificity of 91.21%, accuracy of 91.81%, and area under the ROC curve of 0.94. The results demonstrate the promising performance of texture extraction techniques using mean phylogenetic distance and taxonomic diversity index combined with phylogenetic trees. Graphical Abstract Stages of the proposed methodology.

2008 GEM Modeling Challenge: Metrics Study of the Dst Index in Physics-Based Magnetosphere and Ring Current Models and in Statistical and Analytic Specifications

NASA Technical Reports Server (NTRS)

Rastaetter, L.; Kuznetsova, M.; Hesse, M.; Pulkkinen, A.; Glocer, A.; Yu, Y.; Meng, X.; Raeder, J.; Wiltberger, M.; Welling, D.;

Development of an Algorithm for Satellite Remote Sensing of Sea and Lake Ice

NASA Astrophysics Data System (ADS)

Dorofy, Peter T.

Satellite remote sensing of snow and ice has a long history. The traditional method for many snow and ice detection algorithms has been the use of the Normalized Difference Snow Index (NDSI). This manuscript is composed of two parts. Chapter 1, Development of a Mid-Infrared Sea and Lake Ice Index (MISI) using the GOES Imager, discusses the desirability, development, and implementation of alternative index for an ice detection algorithm, application of the algorithm to the detection of lake ice, and qualitative validation against other ice mapping products; such as, the Ice Mapping System (IMS). Chapter 2, Application of Dynamic Threshold in a Lake Ice Detection Algorithm, continues with a discussion of the development of a method that considers the variable viewing and illumination geometry of observations throughout the day. The method is an alternative to Bidirectional Reflectance Distribution Function (BRDF) models. Evaluation of the performance of the algorithm is introduced by aggregating classified pixels within geometrical boundaries designated by IMS and obtaining sensitivity and specificity statistical measures.

Low loss photonic components in high index bismuth borate glass by femtosecond laser direct writing.

PubMed

Yang, Weijia; Corbari, Costantino; Kazansky, Peter G; Sakaguchi, Koichi; Carvalho, Isabel C S

2008-09-29

Single mode, low loss waveguides were fabricated in high index bismuth borate glass by femtosecond laser direct writing. A specific set of writing parameters leading to waveguides perfectly mode matched to standard single-mode fibers at 1.55 microm with an overall insertion loss of approximately 1 dB and with propagation loss below 0.2 dB/cm was identified. Photonic components such as Y-splitters and directional couplers were also demonstrated. A close agreement between their performances and theoretical predictions based upon the characterization of the waveguide properties is shown. Finally, the nonlinear refractive index of the waveguides has been measured to be 6.6 x 10(-15) cm(2)/W by analyzing self-phase modulation of the propagating femtosecond laser pulse at the wavelength of 1.46 microm. Broadening of the transmitted light source as large as 500 nm was demonstrated through a waveguide with the length of 1.8 cm.

Likelihood ratio-based differentiation of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in patients with sonographically evident diffuse hashimoto thyroiditis: preliminary study.

PubMed

Wang, Liang; Xia, Yu; Jiang, Yu-Xin; Dai, Qing; Li, Xiao-Yi

2012-11-01

To assess the efficacy of sonography for discriminating nodular Hashimoto thyroiditis from papillary thyroid carcinoma in patients with sonographically evident diffuse Hashimoto thyroiditis. This study included 20 patients with 24 surgically confirmed Hashimoto thyroiditis nodules and 40 patients with 40 papillary thyroid carcinoma nodules; all had sonographically evident diffuse Hashimoto thyroiditis. A retrospective review of the sonograms was performed, and significant benign and malignant sonographic features were selected by univariate and multivariate analyses. The combined likelihood ratio was calculated as the product of each feature's likelihood ratio for papillary thyroid carcinoma. We compared the abilities of the original sonographic features and combined likelihood ratios in diagnosing nodular Hashimoto thyroiditis and papillary thyroid carcinoma by their sensitivity, specificity, and Youden index. The diagnostic capabilities of the sonographic features varied greatly, with Youden indices ranging from 0.175 to 0.700. Compared with single features, combinations of features were unable to improve the Youden indices effectively because the sensitivity and specificity usually changed in opposite directions. For combined likelihood ratios, however, the sensitivity improved greatly without an obvious reduction in specificity, which resulted in the maximum Youden index (0.825). With a combined likelihood ratio greater than 7.00 as the diagnostic criterion for papillary thyroid carcinoma, sensitivity reached 82.5%, whereas specificity remained at 100.0%. With a combined likelihood ratio less than 1.00 for nodular Hashimoto thyroiditis, sensitivity and specificity were 90.0% and 92.5%, respectively. Several sonographic features of nodular Hashimoto thyroiditis and papillary thyroid carcinoma in a background of diffuse Hashimoto thyroiditis were significantly different. The combined likelihood ratio may be superior to original sonographic features for discrimination of nodular Hashimoto thyroiditis from papillary thyroid carcinoma; therefore, it is a promising risk index for thyroid nodules and warrants further investigation.

Application of a MRI based index to longitudinal atrophy change in Alzheimer disease, mild cognitive impairment and healthy older individuals in the AddNeuroMed cohort

PubMed Central

Aguilar, Carlos; Muehlboeck, J-Sebastian; Mecocci, Patrizia; Vellas, Bruno; Tsolaki, Magda; Kloszewska, Iwona; Soininen, Hilkka; Lovestone, Simon; Wahlund, Lars-Olof; Simmons, Andrew; Westman, Eric

2014-01-01

Cross sectional studies of patients at risk of developing Alzheimer disease (AD) have identified several brain regions known to be prone to degeneration suitable as biomarkers, including hippocampal, ventricular, and whole brain volume. The aim of this study was to longitudinally evaluate an index based on morphometric measures derived from MRI data that could be used for classification of AD and healthy control subjects, as well as prediction of conversion from mild cognitive impairment (MCI) to AD. Patients originated from the AddNeuroMed project at baseline (119 AD, 119 MCI, 110 controls (CTL)) and 1-year follow-up (62 AD, 73 MCI, 79 CTL). Data consisted of 3D T1-weighted MR images, demographics, MMSE, ADAS-Cog, CERAD and CDR scores, and APOE e4 status. We computed an index using a multivariate classification model (AD vs. CTL), using orthogonal partial least squares to latent structures (OPLS). Sensitivity, specificity and AUC were determined. Performance of the classifier (AD vs. CTL) was high at baseline (10-fold cross-validation, 84% sensitivity, 91% specificity, 0.93 AUC) and at 1-year follow-up (92% sensitivity, 74% specificity, 0.93 AUC). Predictions of conversion from MCI to AD were good at baseline (77% of MCI converters) and at follow-up (91% of MCI converters). MCI carriers of the APOE e4 allele manifested more atrophy and presented a faster cognitive decline when compared to non-carriers. The derived index demonstrated a steady increase in atrophy over time, yielding higher accuracy in prediction at the time of clinical conversion. Neuropsychological tests appeared less sensitive to changes over time. However, taking the average of the two time points yielded better correlation between the index and cognitive scores as opposed to using cross-sectional data only. Thus, multivariate classification seemed to detect patterns of AD changes before conversion from MCI to AD and including longitudinal information is of great importance. PMID:25071554

Involvement of RNA2-encoded proteins in the specific transmission of Grapevine fanleaf virus by its nematode vector Xiphinema index.

PubMed

Belin, C; Schmitt, C; Demangeat, G; Komar, V; Pinck, L; Fuchs, M

2001-12-05

The nepovirus Grapevine fanleaf virus (GFLV) is specifically transmitted by the nematode Xiphinema index. To identify the RNA2-encoded proteins involved in X. index-mediated spread of GFLV, chimeric RNA2 constructs were engineered by replacing the 2A, 2B(MP), and/or 2C(CP) sequences of GFLV with their counterparts in Arabis mosaic virus (ArMV), a closely related nepovirus which is transmitted by Xiphinema diversicaudatum but not by X. index. Among the recombinant viruses obtained from transcripts of GFLV RNA1 and chimeric RNA2, only those which contained the 2C(CP) gene (504 aa) and 2B(MP) contiguous 9 C-terminal residues of GFLV were transmitted by X. index as efficiently as natural and synthetic wild-type GFLV, regardless of the origin of the 2A and 2B(MP) genes. As expected, ArMV was not transmitted probably because it is not retained by X. index. These results indicate that the determinants responsible for the specific spread of GFLV by X. index are located within the 513 C-terminal residues of the polyprotein encoded by RNA2. Copyright 2001 Elsevier Science.

Mercury: Reusable software application for Metadata Management, Data Discovery and Access

NASA Astrophysics Data System (ADS)

Devarakonda, Ranjeet; Palanisamy, Giri; Green, James; Wilson, Bruce E.

2009-12-01

Mercury is a federated metadata harvesting, data discovery and access tool based on both open source packages and custom developed software. It was originally developed for NASA, and the Mercury development consortium now includes funding from NASA, USGS, and DOE. Mercury is itself a reusable toolset for metadata, with current use in 12 different projects. Mercury also supports the reuse of metadata by enabling searching across a range of metadata specification and standards including XML, Z39.50, FGDC, Dublin-Core, Darwin-Core, EML, and ISO-19115. Mercury provides a single portal to information contained in distributed data management systems. It collects metadata and key data from contributing project servers distributed around the world and builds a centralized index. The Mercury search interfaces then allow the users to perform simple, fielded, spatial and temporal searches across these metadata sources. One of the major goals of the recent redesign of Mercury was to improve the software reusability across the projects which currently fund the continuing development of Mercury. These projects span a range of land, atmosphere, and ocean ecological communities and have a number of common needs for metadata searches, but they also have a number of needs specific to one or a few projects To balance these common and project-specific needs, Mercury’s architecture includes three major reusable components; a harvester engine, an indexing system and a user interface component. The harvester engine is responsible for harvesting metadata records from various distributed servers around the USA and around the world. The harvester software was packaged in such a way that all the Mercury projects will use the same harvester scripts but each project will be driven by a set of configuration files. The harvested files are then passed to the Indexing system, where each of the fields in these structured metadata records are indexed properly, so that the query engine can perform simple, keyword, spatial and temporal searches across these metadata sources. The search user interface software has two API categories; a common core API which is used by all the Mercury user interfaces for querying the index and a customized API for project specific user interfaces. For our work in producing a reusable, portable, robust, feature-rich application, Mercury received a 2008 NASA Earth Science Data Systems Software Reuse Working Group Peer-Recognition Software Reuse Award. The new Mercury system is based on a Service Oriented Architecture and effectively reuses components for various services such as Thesaurus Service, Gazetteer Web Service and UDDI Directory Services. The software also provides various search services including: RSS, Geo-RSS, OpenSearch, Web Services and Portlets, integrated shopping cart to order datasets from various data centers (ORNL DAAC, NSIDC) and integrated visualization tools. Other features include: Filtering and dynamic sorting of search results, book-markable search results, save, retrieve, and modify search criteria.

Clinical significance of the FIB-4 index for non-B non-C hepatocellular carcinoma treated with surgical resection.

PubMed

Nishikawa, Hiroki; Osaki, Yukio; Komekado, Hideyuki; Sakamoto, Azusa; Saito, Sumio; Nishijima, Norihiro; Nasu, Akihiro; Arimoto, Akira; Kita, Ryuichi; Kimura, Toru

2015-01-01

The aims of the present study were to examine the relationship between the preoperative FIB-4 index and background liver fibrosis in non-tumor parts obtained from surgical specimens and to investigate whether the FIB-4 index can be a useful predictor for non-B non-C hepatocellular carcinoma (NBNC-HCC) patients treated with surgical resection (SR). A total of 118 patients with NBNC-HCC treated with SR with curative intent were analyzed. Receiver operating characteristic (ROC) curve analysis was performed for calculating the area under the ROC (AUROC) for the FIB-4 index, aspartate aminotransferase (AST) to platelet ratio index, AST to alanine aminotransferase ratio, serum albumin, total bilirubin and platelet count for cirrhosis. We also examined predictors linked to overall survival (OS) and recurrence-free survival (RFS) after SR. The mean patient age was 68.9±9.0 years (93 males and 25 females) with a median observation period of 3.2 years. In extracted surgical specimens, background liver cirrhosis (F4) was observed in 39 patients (33.1%). The mean maximum tumor size was 5.7±3.2 cm. The mean body mass index was 24.3±3.9 kg/m2. The FIB-4 index yielded the highest AUROC for cirrhosis with a level of 0.887 at an optimal cut-off value of 2.97 (sensitivity, 92.3; specificity, 69.6%). In the multivariate analysis, serum α-fetoprotein >40 ng/ml (P=0.026) was the only significant independent predictor linked to OS, while tumor number (P=0.002) and FIB-4 index >2.97 (P=0.044) were significant factors linked to RFS. In conclusion, preoperative FIB-4 index can be a useful predictor for NBNC-HCC patients who undergo SR.

External validation of the CAPRA-S score to predict biochemical recurrence, metastasis and mortality after radical prostatectomy in a European cohort.

PubMed

Tilki, Derya; Mandel, Philipp; Schlomm, Thorsten; Chun, Felix K-H; Tennstedt, Pierre; Pehrke, Dirk; Haese, Alexander; Huland, Hartwig; Graefen, Markus; Salomon, Georg

2015-06-01

The CAPRA-S score predicts prostate cancer recurrence based on pathological information from radical prostatectomy. To our knowledge CAPRA-S has never been externally validated in a European cohort. We independently validated CAPRA-S in a single institution European database. The study cohort comprised 14,532 patients treated with radical prostatectomy between January 1992 and August 2012. Prediction of biochemical recurrence, metastasis and cancer specific mortality by CAPRA-S was assessed by Kaplan-Meier analysis and the c-index. CAPRA-S performance to predict biochemical recurrence was evaluated by calibration plot and decision curve analysis. Median followup was 50.8 months (IQR 25.0-96.0). Biochemical recurrence developed in 20.3% of men at a median of 21.2 months (IQR 7.7-44.9). When stratifying patients by CAPRA-S risk group, estimated 5-year biochemical recurrence-free survival was 91.4%, 70.4% and 29.3% in the low, intermediate and high risk groups, respectively. The CAPRA-S c-index to predict biochemical recurrence, metastasis and cancer specific mortality was 0.80, 0.85 and 0.88, respectively. Metastasis developed in 417 men and 196 men died of prostate cancer. The CAPRA-S score was accurate when applied in a European study cohort. It predicted biochemical recurrence, metastasis and cancer specific mortality after radical prostatectomy with a c-index of greater than 0.80. The score can be valuable in regard to decision making for adjuvant therapy. Copyright © 2015. Published by Elsevier Inc.

Global brain atrophy is associated with physical performance and the risk of falls in older adults with cognitive impairment.

PubMed

Yamada, Minoru; Takechi, Hajime; Mori, Shuhei; Aoyama, Tomoki; Arai, Hidenori

2013-04-01

Falls are common in patients with cognitive disorder. The purpose of this study was to determine whether global brain atrophy is associated with cognitive function, physical performance and fall incidents in older adults with mild cognitive disorder. A total of 31 older adults with mild cognitive disorders (mean age 78.9 ± 7.3 years) were studied, and 10 of them had experienced falls and the others had not in the past 1 year. Cognitive function and physical performance were measured in these patients. Global brain atrophy was determined by the Voxel-Based Specific Regional Analysis System for Alzheimer's Disease software. Fallers showed significantly worse scores than the non-fallers in the Global Brain Atrophy Index, Clock Drawing Test (CDT), Verbal Fluency Test (animal), maximum walking time and Timed Up & Go (TUG) Test. The Global Brain Atrophy Index was correlated with the Verbal Fluency Test (animal; r = -0.522), the Verbal Fluency Test with letter (ka; r = -0.337), CDT (r = -0.547), TUG (r = 0.276) and Five Chair Stands Test (r = 0.303) by age-adjusted correlation analyses. Stepwise regression analysis showed that the Global Brain Atrophy Index (β = 1.265, 95% CI 1.022-1.567) was a significant and independent determinant of falls (R(2) = 0.356, P = 0.003). Global brain atrophy might be indicated as one of the risk factors for falls in older adults with mild cognitive disorders. © 2012 Japan Geriatrics Society.

Simulation Study on Fit Indexes in CFA Based on Data with Slightly Distorted Simple Structure

ERIC Educational Resources Information Center

Beauducel, Andre; Wittmann, Werner W.

2005-01-01

Fit indexes were compared with respect to a specific type of model misspecification. Simple structure was violated with some secondary loadings that were present in the true models that were not specified in the estimated models. The c2 test, Comparative Fit Index, Goodness-of-Fit Index, Incremental Fit Index, Nonnormed Fit Index, root mean…

[Diagnosis of respiratory sleep disorders in newborns with suspected apneas: comparison between nocturnal saturometry and polygraphy].

PubMed

Zenteno, Daniel; Bancalari, Aldo; Navarro, Ximena; Díaz, Valentina; Rodríguez-Núñez, Iván; Brockmann, Pablo

2017-12-01

Night Continuous Saturometry (CSO2) is used in Neonatal Units to detect events of hypoxemia in Newborns (NB) with apnea episodes. Polygraphy (PG) has a larger number of measuring channels. Our goal was to evaluate the diagnostic performance of CSO2 compared to Polygra phy in NB with suspected sleep apneas. Results of CSO2 and PG performed simultaneously in RN with suspected apneas were retrospectively analyzed over a three-year period. A 2-channel Masimo Radical-7® pulse oximeter and an Apnea Link Plus® polygraph with 5 simulta neous recording channels were used. Altered PG was defined as: desaturation index under 80% per hour > 1 and/or number of desaturations under 80% > 20 seconds greater than one in the whole va lidated registry and/or hypoapnea apnea index > 1 event per hour. In parallel, altered SpO2C was de fined when one or both of the 80% saturation criteria were altered. Sensitivity, specificity, predictive values and Likelihood Ratio (LLR) for CSO2 were calculated. Results were expressed in absolute value, with 95% confidence interval. Simultaneous 40 CSO2 and PG were performed; 80% (32/40) of them were preterm infants, 60% (24/40) males. 38% (15/40) of the CSO2 and 15% (6/40) of the PGs were altered (p < 0.05). CSO2 has a 100% Sensitivity, 74% Specificity, 40% VPP, 100% VPN, LLR + 3.78 and LLR-0. In the studied NB, CSO2 has a high diagnostic value, however, it may present false positives; It is suggested to use as a screening method and to perform diagnostic confirmation with another sleep test, such as PG.

Vulnerable land ecosystems classification using spatial context and spectral indices

NASA Astrophysics Data System (ADS)

Ibarrola-Ulzurrun, Edurne; Gonzalo-Martín, Consuelo; Marcello, Javier

2017-10-01

Natural habitats are exposed to growing pressure due to intensification of land use and tourism development. Thus, obtaining information on the vegetation is necessary for conservation and management projects. In this context, remote sensing is an important tool for monitoring and managing habitats, being classification a crucial stage. The majority of image classifications techniques are based upon the pixel-based approach. An alternative is the object-based (OBIA) approach, in which a previous segmentation step merges image pixels to create objects that are then classified. Besides, improved results may be gained by incorporating additional spatial information and specific spectral indices into the classification process. The main goal of this work was to implement and assess object-based classification techniques on very-high resolution imagery incorporating spectral indices and contextual spatial information in the classification models. The study area was Teide National Park in Canary Islands (Spain) using Worldview-2 orthoready imagery. In the classification model, two common indices were selected Normalized Difference Vegetation Index (NDVI) and Optimized Soil Adjusted Vegetation Index (OSAVI), as well as two specific Worldview-2 sensor indices, Worldview Vegetation Index and Worldview Soil Index. To include the contextual information, Grey Level Co-occurrence Matrices (GLCM) were used. The classification was performed training a Support Vector Machine with sufficient and representative number of vegetation samples (Spartocytisus supranubius, Pterocephalus lasiospermus, Descurainia bourgaeana and Pinus canariensis) as well as urban, road and bare soil classes. Confusion Matrices were computed to evaluate the results from each classification model obtaining the highest overall accuracy (90.07%) combining both Worldview indices with the GLCM-dissimilarity.

Rural-Urban Differences in Trends in the Wealth Index in Kenya: 1993–2009

PubMed Central

Egede, Leonard E.; Voronca, Delia; Walker, Rebekah J.; Thomas, Craig

2017-01-01

Background The aim of this study was to construct a wealth index that could be compared over time in order to understand the trends in wealth in Kenya, and determine predictors of change in wealth index. Methods Data was from the Demographic and Health Survey (DHS) program collected in Kenya between 1993 and 2009. Variable categories were collapsed to match and factor analysis was performed on the four year pooled data to generate a harmonized wealth index. Possible predictors of wealth were selected from household variables available for all four years. Household sampling weights and stratification by rural/urban was used. Results Overall, wealth increased in Kenya between 1993 and 2008; however, when stratified no significant increase existed in urban areas, and a significant increase in rural areas specifically between 2003 and 2008. The strongest predictor was education, with more than a standard deviation difference for secondary or higher levels of education over those with no education. The association of gender of the head of household, and whether the head of household had a partner differed between rural and urban areas, with household heads who were women and those that had a partner having more wealth in urban areas, but less wealth in rural areas. Conclusion Wealth in Kenya increased overtime, specifically in rural regions. Differences were seen in predictors of wealth by urban/rural residence, educational level, and gender of the head-of-household, and should be taken into account when planning interventions to target those in disproportionately low wealth brackets. PMID:28619399

The Effect of Body Build and BMI on Aerobic Test Performance in School Children (10-15 Years)

PubMed Central

Slinger, Jantine; Verstappen, Frans; Breda, Eric Van; Kuipers, Harm

2006-01-01

Body Mass Index (BMI) has often questionably been used to define body build. In the present study body build was defined more specifically using fat free mass index (FFMI = fat free mass normalised to the stature) and fat mass index (FMI = fat mass normalised to stature). The body build of an individual is ‘solid’ in individuals with a high FFMI for their FMI and is ‘slender’ in individuals with a low FFMI relative to their FMI. The aim of the present study was to investigate the association between aerobic test performance and body build defined as solid, average or slender in 10 to 15 year old children. Five-hundred-and-two children (53% boys) aged 10 to 15 years of age were included in the study. Aerobic test performance was estimated with an incremental cycle ergometer protocol and a shuttle run test. BMI and percentage fat (by skin folds) were determined to calculate FMI and FFMI. After adjustment for differences in age, gender and body mass the solid group achieved a significantly higher maximal power output (W) and power output relative to body mass (W/kg) during the cycle test (p < 0.05) and a higher shuttle-run score (p < 0.05) compared to the slender group. The power output relative to FFM (W/kg FFM) was comparable (p > 0.05) between different body build groups. This study showed that body build is an important determinant of the aerobic test performance. In contrast, there were no differences in aerobic test performance per kilogramme FFM over the body build groups. This suggests that the body build may be determined by genetic predisposition. Key Points Children with a solid body build perform better in aerobic exercise tests than slender children. The power output relative to fat free mass was comparable in the solid, slender and average group. Besides body composition, body build should be considered related to other performance measurements. PMID:24357967

Color encoding in biologically-inspired convolutional neural networks.

PubMed

Rafegas, Ivet; Vanrell, Maria

2018-05-11

Convolutional Neural Networks have been proposed as suitable frameworks to model biological vision. Some of these artificial networks showed representational properties that rival primate performances in object recognition. In this paper we explore how color is encoded in a trained artificial network. It is performed by estimating a color selectivity index for each neuron, which allows us to describe the neuron activity to a color input stimuli. The index allows us to classify whether they are color selective or not and if they are of a single or double color. We have determined that all five convolutional layers of the network have a large number of color selective neurons. Color opponency clearly emerges in the first layer, presenting 4 main axes (Black-White, Red-Cyan, Blue-Yellow and Magenta-Green), but this is reduced and rotated as we go deeper into the network. In layer 2 we find a denser hue sampling of color neurons and opponency is reduced almost to one new main axis, the Bluish-Orangish coinciding with the dataset bias. In layers 3, 4 and 5 color neurons are similar amongst themselves, presenting different type of neurons that detect specific colored objects (e.g., orangish faces), specific surrounds (e.g., blue sky) or specific colored or contrasted object-surround configurations (e.g. blue blob in a green surround). Overall, our work concludes that color and shape representation are successively entangled through all the layers of the studied network, revealing certain parallelisms with the reported evidences in primate brains that can provide useful insight into intermediate hierarchical spatio-chromatic representations. Copyright © 2018 Elsevier Ltd. All rights reserved.

Diagnostic Accuracy of the Berlin Questionnaire in Detecting Sleep-Disordered Breathing in Patients With a Recent Myocardial Infarction

PubMed Central

Sert Kuniyoshi, Fatima H.; Zellmer, Mark R.; Calvin, Andrew D.; Lopez-Jimenez, Francisco; Albuquerque, Felipe N.; van der Walt, Christelle; Trombetta, Ivani C; Caples, Sean M.; Shamsuzzaman, Abu S.; Bukartyk, Jan; Konecny, Tomas; Gami, Apoor S.; Kara, Tomas

2011-01-01

Background: The Berlin Questionnaire (BQ) has been used to identify patients at high risk for sleep-disordered breathing (SDB) in a variety of populations. However, there are no data regarding the validity of the BQ in detecting the presence of SDB in patients after myocardial infarction (MI). The aim of this study was to determine the performance of the BQ in patients after MI. Methods: We conducted a cross-sectional study of 99 patients who had an MI 1 to 3 months previously. The BQ was administered, scored using the published methods, and followed by completed overnight polysomnography as the “gold standard.” SDB was defined as an apnea-hypopnea index of ≥ 5 events/h. The sensitivity, specificity, and positive and negative predictive values of the BQ were calculated. Results: Of the 99 patients, the BQ identified 64 (65%) as being at high-risk for having SDB. Overnight polysomnography showed that 73 (73%) had SDB. The BQ sensitivity and specificity was 0.68 and 0.34, respectively, with a positive predictive value of 0.68 and a negative predictive value of 0.50. Positive and negative likelihood ratios were 1.27 and 0.68, respectively, and the BQ overall diagnostic accuracy was 63%. Using different apnea-hypopnea index cutoff values did not meaningfully alter these results. Conclusion: The BQ performed with modest sensitivity, but the specificity was poor, suggesting that the BQ is not ideal in identifying SDB in patients with a recent MI. PMID:21596794

Prediction and Stability of Mathematics Skill and Difficulty

PubMed Central

Martin, Rebecca B.; Cirino, Paul T.; Barnes, Marcia A.; Ewing-Cobbs, Linda; Fuchs, Lynn S.; Stuebing, Karla K.; Fletcher, Jack M.

2016-01-01

The present study evaluated the stability of math learning difficulties over a 2-year period and investigated several factors that might influence this stability (categorical vs. continuous change, liberal vs. conservative cut point, broad vs. specific math assessment); the prediction of math performance over time and by performance level was also evaluated. Participants were 144 students initially identified as having a math difficulty (MD) or no learning difficulty according to low achievement criteria in the spring of Grade 3 or Grade 4. Students were reassessed 2 years later. For both measure types, a similar proportion of students changed whether assessed categorically or continuously. However, categorical change was heavily dependent on distance from the cut point and so more common for MD, who started closer to the cut point; reliable change index change was more similar across groups. There were few differences with regard to severity level of MD on continuous metrics or in terms of prediction. Final math performance on a broad computation measure was predicted by behavioral inattention and working memory while considering initial performance; for a specific fluency measure, working memory was not uniquely related, and behavioral inattention more variably related to final performance, again while considering initial performance. PMID:22392890

Prediction and stability of mathematics skill and difficulty.

PubMed

Martin, Rebecca B; Cirino, Paul T; Barnes, Marcia A; Ewing-Cobbs, Linda; Fuchs, Lynn S; Stuebing, Karla K; Fletcher, Jack M

2013-01-01

The present study evaluated the stability of math learning difficulties over a 2-year period and investigated several factors that might influence this stability (categorical vs. continuous change, liberal vs. conservative cut point, broad vs. specific math assessment); the prediction of math performance over time and by performance level was also evaluated. Participants were 144 students initially identified as having a math difficulty (MD) or no learning difficulty according to low achievement criteria in the spring of Grade 3 or Grade 4. Students were reassessed 2 years later. For both measure types, a similar proportion of students changed whether assessed categorically or continuously. However, categorical change was heavily dependent on distance from the cut point and so more common for MD, who started closer to the cut point; reliable change index change was more similar across groups. There were few differences with regard to severity level of MD on continuous metrics or in terms of prediction. Final math performance on a broad computation measure was predicted by behavioral inattention and working memory while considering initial performance; for a specific fluency measure, working memory was not uniquely related, and behavioral inattention more variably related to final performance, again while considering initial performance.

Nucleic acid indexing

DOEpatents

Guilfoyle, Richard A.; Guo, Zhen

2001-01-01

A restriction site indexing method for selectively amplifying any fragment generated by a Class II restriction enzyme includes adaptors specific to fragment ends containing adaptor indexing sequences complementary to fragment indexing sequences near the termini of fragments generated by Class II enzyme cleavage. A method for combinatorial indexing facilitates amplification of restriction fragments whose sequence is not known.

Nucleic acid indexing

DOEpatents

Guilfoyle, Richard A.; Guo, Zhen

1999-01-01

A restriction site indexing method for selectively amplifying any fragment generated by a Class II restriction enzyme includes adaptors specific to fragment ends containing adaptor indexing sequences complementary to fragment indexing sequences near the termini of fragments generated by Class II enzyme cleavage. A method for combinatorial indexing facilitates amplification of restriction fragments whose sequence is not known.

Performance of Malaysian Medical Journals

PubMed Central

Abrizah, Abdullah

2016-01-01

Indexation status matters for scholarly journal prestige and trust. The performance of Malaysian medical journals at the international level is gauged through the global citation databases, and at the national level through MyCite, a national citation indexing system. The performance indicators include journals publication productivity, the citations they garner, and their scores on other bibliometric indices such as journal impact factor (IF), and h-index. There is a growing consciousness amongst journal editorials to improve quality and increase chances of getting indexed in MyCite. Although it is now possible to gauge journal performance within Malaysia, through MyCite, the government and public are concerned about journal performance in international databases. Knowing the performance of journals in MyCite will help the editors and publishers to improve the quality and visibility of Malaysian journals and strategise to bring their journal to the international level of indexation. PMID:27547108

Computer-aided interpretation approach for optical tomographic images

NASA Astrophysics Data System (ADS)

Klose, Christian D.; Klose, Alexander D.; Netz, Uwe J.; Scheel, Alexander K.; Beuthan, Jürgen; Hielscher, Andreas H.

2010-11-01

A computer-aided interpretation approach is proposed to detect rheumatic arthritis (RA) in human finger joints using optical tomographic images. The image interpretation method employs a classification algorithm that makes use of a so-called self-organizing mapping scheme to classify fingers as either affected or unaffected by RA. Unlike in previous studies, this allows for combining multiple image features, such as minimum and maximum values of the absorption coefficient for identifying affected and not affected joints. Classification performances obtained by the proposed method were evaluated in terms of sensitivity, specificity, Youden index, and mutual information. Different methods (i.e., clinical diagnostics, ultrasound imaging, magnet resonance imaging, and inspection of optical tomographic images), were used to produce ground truth benchmarks to determine the performance of image interpretations. Using data from 100 finger joints, findings suggest that some parameter combinations lead to higher sensitivities, while others to higher specificities when compared to single parameter classifications employed in previous studies. Maximum performances are reached when combining the minimum/maximum ratio of the absorption coefficient and image variance. In this case, sensitivities and specificities over 0.9 can be achieved. These values are much higher than values obtained when only single parameter classifications were used, where sensitivities and specificities remained well below 0.8.

Impact of pre-operative body mass index in head and neck cancer patients undergoing microvascular reconstruction.

PubMed

Hyun, D-J; Joo, Y-H; Kim, M-S

2017-11-01

To analyse the relationship of pre-operative body mass index with surgical complications and oncological outcomes in patients undergoing microvascular reconstruction for head and neck squamous cell cancer. A retrospective review was conducted of 259 patients who underwent microvascular free flap reconstruction after head and neck ablative surgery. Mean body mass index was 22.48 kg/m2. There were no correlations between body mass index and: flap failure (p = 0.739), flap ischaemia (p = 0.644), pharyngocutaneous fistula (p = 0.141) or wound infection (p = 0.224). The five-year disease-specific survival rate was 63 per cent. On univariate analysis, the five-year disease-specific survival rate was significantly correlated with pre-operative body mass index, based on Kaplan-Meier survival curves (p = 0.028). The five-year disease-specific survival rates in underweight, normal weight, overweight and obese groups were 47 per cent, 55 per cent, 65 per cent and 80 per cent, respectively. Pre-operative body mass index was a useful predictor for recurrence and survival in patients who underwent microvascular reconstruction for head and neck squamous cell cancer.

Systematic review of the links between human resource management practices and performance.

PubMed

Patterson, M; Rick, J; Wood, S; Carroll, C; Balain, S; Booth, A

2010-10-01

In recent years human resource management (HRM) has been seen as an important factor in the successful realisation of organisational change programmes. The UK NHS is undergoing substantial organisational change and there is a need to establish which human resource (HR) initiatives may be most effective. To assess the results from a wide-ranging series of systematic reviews of the evidence on HRM and performance. The first part assesses evidence on use of HRM in the UK and fidelity of practice implemented. The second part considers evidence for the impact of HRM practices on intermediate outcomes, which can impact on final outcomes, such as organisational performance or patient care. The following databases were searched: Applied Social Sciences Index and Abstracts (ASSIA), British Nursing Index (BNI), Business Source Premier, Campbell Collaboration, Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews (CDSR), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Database of Abstracts of Reviews of Effectiveness (DARE), DH-Data, EMBASE, Health Management Information Consortium (HMIC), International Bibliography of the Social Sciences (IBSS), King's Fund database, MEDLINE, NHS Economic Evaluation Database (NHS EED), National Research Register (NRR), PREMEDLINE, PsycINFO, ReFeR, Social Sciences Citation Index (SSCI) and Science Citation Index (SCI). The searches were conducted in May/June 2006. Broad categories of HRM interventions and intermediate outcomes were generated: 10 HRM categories and 12 intermediate outcome categories. Seven patient final outcomes were derived from the NHS Performance Indicators and the NHS Improvement Plan. The quality criteria used to select papers incorporated a longitudinal study design filter to provide evidence of the causal direction of relationships between HRM and relevant outcomes. Single HRM practices were considered. Within the health-specific literature, focus was on the impact of HRM on patient outcomes. Information is presented on the reliability of measures in each of the intermediate outcome areas. Work design practices that enhance employee autonomy and control influenced a number of outcomes and there was consistent evidence for the positive impact of increased job control on employee outcomes, such as job satisfaction, absence and health. For employee participation, the small number of studies reviewed supported the involvement of employees in design/implementation of changes that affect their work. In health literature in particular, employee involvement through quality improvement teams resulted in improved patient outcomes. Findings were positive for the impact of training on the intended outcomes of the initiatives. Support for the impact of performance management practices was apparent, in particular feedback on performance outcomes and the use of participative goal setting. Strong associations were found among all intermediate outcomes, and the relationship between most intermediate behaviours and outcomes were significant. Limited evidence was available on the use of HRM and on the implementation of policy. Also, the specific practices studied within each HRM category differ so there was little evidence to show whether similar practices have the same effects in health and non-health settings. Some potentially effective practices for both health and non-health areas were identified, and HRM methods could be used to support change processes within the NHS; the findings relating to work organisation are particularly promising with regard to changes in methods of service delivery. Using training to support the implementation of change is highlighted. However, future multilevel studies that embrace the individual, team and organisational level are needed. Studies should look into interventions aimed at improving HR outcomes and performance, and allow for pre- and post-intervention measurement of practices and outcomes.

Voice Handicap Index and Interpretation of the Cutoff Points Using Receiver Operating Characteristic Curve as Screening for Young Adult Female Smokers.

PubMed

Tafiadis, Dionysios; Kosma, Evangelia I; Chronopoulos, Spyridon K; Papadopoulos, Aggelos; Drosos, Konstantinos; Siafaka, Vassiliki; Toki, Eugenia I; Ziavra, Nausica

2018-01-01

The relationship between smoking and alterations of the vocal tract and larynx is well known. This pathology leads to the degradation of voice performance in daily living. Multiple assessment methods of vocal tract and larynx have been developed, and in recent years they were enriched with self-reported questionnaires such as Voice Handicap Index (VHI). This study determined the cutoff points of VHI's total score and its three domains for young female smokers in Greece. These estimated cutoff points could be used by voice specialists as an indicator for further clinical evaluation (foreseeing a potential risk of developing a vocal symptom because of smoking habits). A sample of 120 female nondysphonic smokers (aged 18-31) was recruited. Participants filled out the VHI and Voice Evaluation Form. VHI's cutoff point of total score was calculated at the value of 19.50 (sensitivity: 0.780, 1-specificity: 0.133). Specifically, the construct domain of functional was 7.50 (sensitivity: 0.900, 1-specificity: 0.217), for physical it was 8.50 (sensitivity: 0.867, 1-specificity: 0.483), and for emotional it was 7.50 (sensitivity: 0.833, 1-specificity: 0.200) through the use of receiver operating characteristic. Furthermore, VHI could be used as a monitoring tool for smokers and as a feedback for smoking cessation. Copyright © 2018 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

Physiological profiles and sport specific fitness of Asian elite squash players.

PubMed Central

Chin, M K; Steininger, K; So, R C; Clark, C R; Wong, A S

1995-01-01

There is a scarcity of descriptive data on the physiological characteristics of elite Asian squash players. The purpose of this study was to evaluate the physiological profile and sports specific fitness of Hong Kong elite squash players. It was conducted before the selection of the Hong Kong national squash team for the 1992 Asian Squash Championship. Ten elite squash players were selected as subjects for the study. Maximum oxygen uptake was measured using a continuous treadmill running test. A sports specific field test was performed in a squash court. The following means (s.d.) were observed: height 172.6(4.3) cm; weight 67.7(6.9) kg; body fat 7.4(3.4)%; forced vital capacity (FVC) 5.13(0.26) litres; maximum oxygen uptake (VO2max) 61.7(3.4) ml.kg-1.min-1; anaerobic threshold (AT) 80.2(3.3)% of VO2max; alactic power index 15.5(1.8) W.kg-1; lactic work index 323.5(29.4) J.kg-1, peak isokinetic dominant knee extensor and flexor strengths 3.11(0.29) Nm.kg-1 and 1.87(0.18) Nm.kg-1. The results show that the Hong Kong squash players have relatively high cardiorespiratory sports specific fitness and muscle strength which may be one of the key factors that contributed to the success of the Hong Kong team in the Asian Championship. PMID:8800847

Training Attentional Control Improves Cognitive and Motor Task Performance.

PubMed

Ducrocq, Emmanuel; Wilson, Mark; Vine, Sam; Derakshan, Nazanin

2016-10-01

Attentional control is a necessary function for the regulation of goal-directed behavior. In three experiments we investigated whether training inhibitory control using a visual search task could improve task-specific measures of attentional control and performance. In Experiment 1 results revealed that training elicited a near-transfer effect, improving performance on a cognitive (antisaccade) task assessing inhibitory control. In Experiment 2 an initial far-transfer effect of training was observed on an index of attentional control validated for tennis. The principal aim of Experiment 3 was to expand on these findings by assessing objective gaze measures of inhibitory control during the performance of a tennis task. Training improved inhibitory control and performance when pressure was elevated, confirming the mechanisms by which cognitive anxiety impacts performance. These results suggest that attentional control training can improve inhibition and reduce taskspecific distractibility with promise of transfer to more efficient sporting performance in competitive contexts.

Controlling automatic imitative tendencies: interactions between mirror neuron and cognitive control systems.

PubMed

Cross, Katy A; Torrisi, Salvatore; Reynolds Losin, Elizabeth A; Iacoboni, Marco

2013-12-01

Humans have an automatic tendency to imitate others. Although several regions commonly observed in social tasks have been shown to be involved in imitation control, there is little work exploring how these regions interact with one another. We used fMRI and dynamic causal modeling to identify imitation-specific control mechanisms and examine functional interactions between regions. Participants performed a pre-specified action (lifting their index or middle finger) in response to videos depicting the same two actions (biological cues) or dots moving with similar trajectories (non-biological cues). On congruent trials, the stimulus and response were similar (e.g. index finger response to index finger or left side dot stimulus), while on incongruent trials the stimulus and response were dissimilar (e.g. index finger response to middle finger or right side dot stimulus). Reaction times were slower on incongruent compared to congruent trials for both biological and non-biological stimuli, replicating previous findings that suggest the automatic imitative or spatially compatible (congruent) response must be controlled on incongruent trials. Neural correlates of the congruency effects were different depending on the cue type. The medial prefrontal cortex, anterior cingulate, inferior frontal gyrus pars opercularis (IFGpo) and the left anterior insula were involved specifically in controlling imitation. In addition, the IFGpo was also more active for biological compared to non-biological stimuli, suggesting that the region represents the frontal node of the human mirror neuron system (MNS). Effective connectivity analysis exploring the interactions between these regions, suggests a role for the mPFC and ACC in imitative conflict detection and the anterior insula in conflict resolution processes, which may occur through interactions with the frontal node of the MNS. We suggest an extension of the previous models of imitation control involving interactions between imitation-specific and general cognitive control mechanisms. © 2013.

Prognostic assessment in COPD without lung function: the B-AE-D indices.

PubMed

Boeck, Lucas; Soriano, Joan B; Brusse-Keizer, Marjolein; Blasi, Francesco; Kostikas, Konstantinos; Boersma, Wim; Milenkovic, Branislava; Louis, Renaud; Lacoma, Alicia; Djamin, Remco; Aerts, Joachim; Torres, Antoni; Rohde, Gernot; Welte, Tobias; Martinez-Camblor, Pablo; Rakic, Janko; Scherr, Andreas; Koller, Michael; van der Palen, Job; Marin, Jose M; Alfageme, Inmaculada; Almagro, Pere; Casanova, Ciro; Esteban, Cristobal; Soler-Cataluña, Juan J; de-Torres, Juan P; Miravitlles, Marc; Celli, Bartolome R; Tamm, Michael; Stolz, Daiana

2016-06-01

Several composite markers have been proposed for risk assessment in chronic obstructive pulmonary disease (COPD). However, choice of parameters and score complexity restrict clinical applicability. Our aim was to provide and validate a simplified COPD risk index independent of lung function.The PROMISE study (n=530) was used to develop a novel prognostic index. Index performance was assessed regarding 2-year COPD-related mortality and all-cause mortality. External validity was tested in stable and exacerbated COPD patients in the ProCOLD, COCOMICS and COMIC cohorts (total n=2988).Using a mixed clinical and statistical approach, body mass index (B), severe acute exacerbations of COPD frequency (AE), modified Medical Research Council dyspnoea severity (D) and copeptin (C) were identified as the most suitable simplified marker combination. 0, 1 or 2 points were assigned to each parameter and totalled to B-AE-D or B-AE-D-C. It was observed that B-AE-D and B-AE-D-C were at least as good as BODE (body mass index, airflow obstruction, dyspnoea, exercise capacity), ADO (age, dyspnoea, airflow obstruction) and DOSE (dyspnoea, obstruction, smoking, exacerbation) indices for predicting 2-year all-cause mortality (c-statistic: 0.74, 0.77, 0.69, 0.72 and 0.63, respectively; Hosmer-Lemeshow test all p>0.05). Both indices were COPD specific (c-statistic for predicting COPD-related 2-year mortality: 0.87 and 0.89, respectively). External validation of B-AE-D was performed in COCOMICS and COMIC (c-statistic for 1-year all-cause mortality: 0.68 and 0.74; c-statistic for 2-year all-cause mortality: 0.65 and 0.67; Hosmer-Lemeshow test all p>0.05).The B-AE-D index, plus copeptin if available, allows a simple and accurate assessment of COPD-related risk. Copyright ©ERS 2016.

Prognostic assessment in COPD without lung function: the B-AE-D indices

PubMed Central

Boeck, Lucas; Blasi, Francesco; Kostikas, Konstantinos; Boersma, Wim; Milenkovic, Branislava; Louis, Renaud; Lacoma, Alicia; Djamin, Remco; Aerts, Joachim; Torres, Antoni; Rohde, Gernot; Welte, Tobias; Martinez-Camblor, Pablo; Rakic, Janko; Scherr, Andreas; Koller, Michael; van der Palen, Job; Marin, Jose M.; Alfageme, Inmaculada; Almagro, Pere; Casanova, Ciro; Esteban, Cristobal; Soler-Cataluña, Juan J.; de-Torres, Juan P.; Miravitlles, Marc; Celli, Bartolome R.; Tamm, Michael

2016-01-01

Several composite markers have been proposed for risk assessment in chronic obstructive pulmonary disease (COPD). However, choice of parameters and score complexity restrict clinical applicability. Our aim was to provide and validate a simplified COPD risk index independent of lung function. The PROMISE study (n=530) was used to develop a novel prognostic index. Index performance was assessed regarding 2-year COPD-related mortality and all-cause mortality. External validity was tested in stable and exacerbated COPD patients in the ProCOLD, COCOMICS and COMIC cohorts (total n=2988). Using a mixed clinical and statistical approach, body mass index (B), severe acute exacerbations of COPD frequency (AE), modified Medical Research Council dyspnoea severity (D) and copeptin (C) were identified as the most suitable simplified marker combination. 0, 1 or 2 points were assigned to each parameter and totalled to B-AE-D or B-AE-D-C. It was observed that B-AE-D and B-AE-D-C were at least as good as BODE (body mass index, airflow obstruction, dyspnoea, exercise capacity), ADO (age, dyspnoea, airflow obstruction) and DOSE (dyspnoea, obstruction, smoking, exacerbation) indices for predicting 2-year all-cause mortality (c-statistic: 0.74, 0.77, 0.69, 0.72 and 0.63, respectively; Hosmer–Lemeshow test all p>0.05). Both indices were COPD specific (c-statistic for predicting COPD-related 2-year mortality: 0.87 and 0.89, respectively). External validation of B-AE-D was performed in COCOMICS and COMIC (c-statistic for 1-year all-cause mortality: 0.68 and 0.74; c-statistic for 2-year all-cause mortality: 0.65 and 0.67; Hosmer–Lemeshow test all p>0.05). The B-AE-D index, plus copeptin if available, allows a simple and accurate assessment of COPD-related risk. PMID:27103389

Developmental Change in the Influence of Domain-General Abilities and Domain-Specific Knowledge on Mathematics Achievement: An Eight-Year Longitudinal Study

ERIC Educational Resources Information Center

Geary, David C.; Nicholas, Alan; Li, Yaoran; Sun, Jianguo

2017-01-01

The contributions of domain-general abilities and domain-specific knowledge to subsequent mathematics achievement were longitudinally assessed (n = 167) through 8th grade. First grade intelligence and working memory and prior grade reading achievement indexed domain-general effects, and domain-specific effects were indexed by prior grade…

Improved Numerical Calculation of the Single-Mode-No-Core-Single-Mode Fiber Structure Using the Fields Far from Cutoff Approximation

PubMed Central

Yang, Xianchao; Xu, Degang; Rong, Feng; Zhao, Junfa; Yao, Jianquan

2017-01-01

Multimode interferometers based on the single-mode-no-core-single-mode fiber (SNCS) structure have been widely investigated as functional devices and sensors. However, the theoretical support for the sensing mechanism is still imperfect, especially for the cladding refractive index response. In this paper, a modified model of no-core fiber (NCF) based on far from cut-off approximation is proposed to investigate the spectrum characteristic and sensing mechanism of the SNCS structure. Guided-mode propagation analysis (MPA) is used to analyze the self-image effect and spectrum response to the cladding refractive index and temperature. Verified by experiments, the performance of the SNCS structure can be estimated specifically and easily by the proposed method. PMID:28961174

NASA Video Catalog. Supplement 15

NASA Technical Reports Server (NTRS)

2005-01-01

This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Coverage Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

NASA Video Catalog. Supplement 13

NASA Technical Reports Server (NTRS)

2003-01-01

This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Coverage Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

NASA Video Catalog. Supplement 14

NASA Technical Reports Server (NTRS)

2004-01-01

This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Coverage Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

NASA Video Catalog

NASA Technical Reports Server (NTRS)

2006-01-01

This issue of the NASA Video Catalog cites video productions listed in the NASA STI database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The Table of Contents shows how the entries are arranged by divisions and categories according to the NASA Scope and Subject Category Guide. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

Intellectual Profiles in the Autism Spectrum and Other Neurodevelopmental Disorders.

PubMed

Mouga, Susana; Café, Cátia; Almeida, Joana; Marques, Carla; Duque, Frederico; Oliveira, Guiomar

2016-09-01

The influence of specific autism spectrum disorder (ASD) deficits in Intelligence Quotients (IQ), Indexes and subtests from the Wechsler Intelligence Scale for Children-III was investigated in 445 school-aged children: ASD (N = 224) and other neurodevelopmental disorders (N = 221), matched by Full-Scale IQ and chronological age. ASD have lower scores in the VIQ than PIQ. The core distinctive scores between groups are Processing Speed Index and "Comprehension" and "Coding" subtests with lower results in ASD. ASD group with normal/high IQ showed highest score on "Similarities" subtest whereas the lower IQ group performed better on "Object Assembly". The results replicated our previous work on adaptive behaviour, showing that adaptive functioning is positively correlated with intellectual profile, especially with the Communication domain in ASD.

Annotated Administrative Record Site-Specific Document Index, American Drum & Pallet Co. Removal Site, Memphis, Shelby County, Tennessee

EPA Pesticide Factsheets

Contains annotated index of site specific documents for the American Drum & Pallet Co. Removal Site in Memphis, Shelby County, Tennessee, January 9, 2008 Region ID: 04 DocID: 10517016, DocDate: 01-09-2008

Explosive Characteristics of Carbonaceous Nanoparticles

NASA Astrophysics Data System (ADS)

Turkevich, Leonid; Fernback, Joseph; Dastidar, Ashok

2013-03-01

Explosion testing has been performed on 20 codes of carbonaceous particles. These include SWCNTs (single-walled carbon nanotubes), MWCNTs (multi-walled carbon nanotubes), CNFs (carbon nanofibers), graphene, diamond, fullerene, carbon blacks and graphites. Explosion screening was performed in a 20 L explosion chamber (ASTM E1226-10 protocol), at a (dilute) concentration of 500 g/m3, using a 5 kJ ignition source. Time traces of overpressure were recorded. Samples exhibited overpressures of 5-7 bar, and deflagration index KSt = V1/3 (dp/pt)max ~ 10 - 80 bar-m/s, which places these materials in European Dust Explosion Class St-1 (similar to cotton and wood dust). There was minimal variation between these different materials. The explosive characteristics of these carbonaceous powders are uncorrelated with particle size (BET specific surface area). Additional tests were performed on selected materials to identify minimum explosive concentration [MEC]. These materials exhibit MEC ~ 101 -102 g/m3 (lower than the MEC for coals). The concentration scans confirm that the earlier screening was performed under fuel-rich conditions (i.e. the maximum over-pressure and deflagration index exceed the screening values); e.g. the true fullerene KSt ~ 200 bar-m/s, placing it borderline St-1/St-2. Work supported through the NIOSH Nanotechnology Research Center (NTRC)

Associations of Body Mass Index, Motor Performance, and Perceived Athletic Competence with Physical Activity in Normal Weight and Overweight Children

PubMed Central

Cairney, John; Eisenmann, Joe; Pfeiffer, Karin; Gould, Dan

2018-01-01

Children who are overweight and obese display lower physical activity levels than normal weight peers. Measures of weight status, perceived motor competence, and motor skill performance have been identified as potential correlates explaining this discrepancy. 1881 children (955 males; 926 females; 9.9 years) were assessed as part of the Physical Health Activity Study Team project. The age, habitual physical activity participation (PAP), body mass index (BMI), socioeconomic status (SES), motor performance (MP), and perceived athletic competence (PAC) of each child included were assessed. Gender-specific linear regression analyses (main effects model) were conducted to identify the percent variance in PAP explained by the following variables: BMI, MP, and PAC. For males, 18.3% of the variance in PAP was explained by BMI, MP, and PAC. PAC explained 17% of the variance, while MP, BMI, and SES only accounted for 0.6%, 0.7%, and 0.5%, respectively. PAC explained 17.5% of PAP variance in females; MP explained 0.8%. BMI, SES, and chronological age were not significant correlates of PAP in girls. An established repertoire of motor skill performance has been seen as a vehicle to PAP in children; however, this study indicates that PAC should not be overlooked in intervention strategies to promote increased PAP. PMID:29854437

Associations of Body Mass Index, Motor Performance, and Perceived Athletic Competence with Physical Activity in Normal Weight and Overweight Children.

PubMed

Morrison, Kyle M; Cairney, John; Eisenmann, Joe; Pfeiffer, Karin; Gould, Dan

2018-01-01

Children who are overweight and obese display lower physical activity levels than normal weight peers. Measures of weight status, perceived motor competence, and motor skill performance have been identified as potential correlates explaining this discrepancy. 1881 children (955 males; 926 females; 9.9 years) were assessed as part of the Physical Health Activity Study Team project. The age, habitual physical activity participation (PAP), body mass index (BMI), socioeconomic status (SES), motor performance (MP), and perceived athletic competence (PAC) of each child included were assessed. Gender-specific linear regression analyses (main effects model) were conducted to identify the percent variance in PAP explained by the following variables: BMI, MP, and PAC. For males, 18.3% of the variance in PAP was explained by BMI, MP, and PAC. PAC explained 17% of the variance, while MP, BMI, and SES only accounted for 0.6%, 0.7%, and 0.5%, respectively. PAC explained 17.5% of PAP variance in females; MP explained 0.8%. BMI, SES, and chronological age were not significant correlates of PAP in girls. An established repertoire of motor skill performance has been seen as a vehicle to PAP in children; however, this study indicates that PAC should not be overlooked in intervention strategies to promote increased PAP.

Characterisation of the responsive properties of two running-specific prosthetic models.

PubMed

Grobler, Lara; Ferreira, Suzanne; Vanwanseele, Benedicte; Terblanche, Elmarie E

2017-04-01

The need for information regarding running-specific prosthetic properties has previously been voiced. Such information is necessary to assist in athletes' prostheses selection. This study aimed to describe the characteristics of two commercially available running-specific prostheses. The running-specific prostheses were tested (in an experimental setup) without the external interference of athlete performance variations. Four stiffness categories of each running-specific prosthetic model (Xtend ™ and Xtreme ™ ) were tested at seven alignment setups and three drop masses (28, 38 and 48 kg). Results for peak ground reaction force (GRF peak ), contact time ( t c ), flight time ( t f ), reactive strength index (RSI) and maximal compression (Δ L) were determined during controlled dropping of running-specific prostheses onto a force platform with different masses attached to the experimental setup. No statistically significant differences were found between the different setups of the running-specific prostheses. Statistically significant differences were found between the two models for all outcome variables (GRF peak , Xtend > Xtreme; t c , Xtreme > Xtend; t f , Xtreme > Xtend; RSI, Xtend > Xtreme; Δ L, Xtreme > Xtend; p < 0.05). These findings suggest that the Xtreme stores more elastic energy than the Xtend, leading to a greater performance response. The specific responsive features of blades could guide sprint athletes in their choice of running-specific prostheses. Clinical relevance Insights into the running-specific prosthesis (RSP) properties and an understanding of its responsive characteristics have implications for athletes' prosthetic choice. Physiologically and metabolically, a short sprint event (i.e. 100 m) places different demands on the athlete than a long sprint event (i.e. 400 m), and the RSP should match these performance demands.

Positron emission mammography in breast cancer presurgical planning: comparisons with magnetic resonance imaging

PubMed Central

Narayanan, Deepa; Kalinyak, Judith E.; The, Juliette; Velasquez, Maria Victoria; Kahn, Simone; Saady, Matthew; Mahal, Ravinder; Chrystal, Larraine

2010-01-01

Purpose The objective of this study was to compare the performance characteristics of 18F-fluorodeoxyglucose (FDG) positron emission mammography (PEM) with breast magnetic resonance imaging (MRI) as a presurgical imaging and planning option for index and ipsilateral lesions in patients with newly diagnosed, biopsy-proven breast cancer. Methods Two hundred and eight women >25 years of age (median age = 59.7 ± 14.1 years) with biopsy-proven primary breast cancer enrolled in this prospective, single-site study. MRI, PEM, and whole-body positron emission tomography (WBPET) were conducted on each patient within 7 business days. PEM and WBPET images were acquired on the same day after intravenous administration of 370 MBq of FDG (median = 432.9 MBq). PEM and MRI images were blindly evaluated, compared with final surgical histopathology, and the sensitivity determined. Substudy analysis compared the sensitivity of PEM versus MRI in patients with different menopausal status, breast density, and use of hormone replacement therapy (HRT) as well as determination of performance characteristics for additional ipsilateral lesion detection. Results Two hundred and eight patients enrolled in the study of which 87% (182/208) were analyzable. Of these analyzable patients, 26.4% (48/182), 7.1% (13/182), and 64.2% (120/182) were pre-, peri-, and postmenopausal, respectively, and 48.4% (88/182) had extremely or heterogeneously dense breast tissue, while 33.5% (61/182) had a history of HRT use. Ninety-two percent (167/182) underwent core biopsy for index lesion diagnosis. Invasive cancer was found in 77.5% (141/182), while ductal carcinoma in situ (DCIS) and/or Paget’s disease were found in 22.5% (41/182) of patients. Both PEM and MRI had index lesion depiction sensitivity of 92.8% and both were significantly better than WBPET (67.9%, p < 0.001, McNemar’s test). For index lesions, PEM and MRI had equivalent sensitivity of various tumors, categorized by tumor stage as well as similar invasive tumor size predictions with Spearman's correlation coefficient of 0.61 for both PEM and MRI compared to surgical pathology. Menopausal status, breast density, and HRT did not influence the sensitivity of PEM or MRI. For 67 additional unsuspected ipsilateral lesions or multifocal lesions, PEM had sensitivity of 85% (34/40) and specificity of 74%, (20/27) compared to MRI's sensitivity of 98% (39/40) and specificity of 48% (13/27) [p = 0.074, for sensitivity; p = 0.096 for specificity] Conclusion PEM is a good alternative to MRI as a presurgical breast imaging option and its performance characteristics are not affected by patient menopausal/hormonal status or breast density. PMID:20871992

Positron emission mammography in breast cancer presurgical planning: comparisons with magnetic resonance imaging.

PubMed

Schilling, Kathy; Narayanan, Deepa; Kalinyak, Judith E; The, Juliette; Velasquez, Maria Victoria; Kahn, Simone; Saady, Matthew; Mahal, Ravinder; Chrystal, Larraine

2011-01-01

The objective of this study was to compare the performance characteristics of (18)F-fluorodeoxyglucose (FDG) positron emission mammography (PEM) with breast magnetic resonance imaging (MRI) as a presurgical imaging and planning option for index and ipsilateral lesions in patients with newly diagnosed, biopsy-proven breast cancer. Two hundred and eight women >25 years of age (median age = 59.7 ± 14.1 years) with biopsy-proven primary breast cancer enrolled in this prospective, single-site study. MRI, PEM, and whole-body positron emission tomography (WBPET) were conducted on each patient within 7 business days. PEM and WBPET images were acquired on the same day after intravenous administration of 370 MBq of FDG (median = 432.9 MBq). PEM and MRI images were blindly evaluated, compared with final surgical histopathology, and the sensitivity determined. Substudy analysis compared the sensitivity of PEM versus MRI in patients with different menopausal status, breast density, and use of hormone replacement therapy (HRT) as well as determination of performance characteristics for additional ipsilateral lesion detection. Two hundred and eight patients enrolled in the study of which 87% (182/208) were analyzable. Of these analyzable patients, 26.4% (48/182), 7.1% (13/182), and 64.2% (120/182) were pre-, peri-, and postmenopausal, respectively, and 48.4% (88/182) had extremely or heterogeneously dense breast tissue, while 33.5% (61/182) had a history of HRT use. Ninety-two percent (167/182) underwent core biopsy for index lesion diagnosis. Invasive cancer was found in 77.5% (141/182), while ductal carcinoma in situ (DCIS) and/or Paget's disease were found in 22.5% (41/182) of patients. Both PEM and MRI had index lesion depiction sensitivity of 92.8% and both were significantly better than WBPET (67.9%, p < 0.001, McNemar's test). For index lesions, PEM and MRI had equivalent sensitivity of various tumors, categorized by tumor stage as well as similar invasive tumor size predictions with Spearman's correlation coefficient of 0.61 for both PEM and MRI compared to surgical pathology. Menopausal status, breast density, and HRT did not influence the sensitivity of PEM or MRI. For 67 additional unsuspected ipsilateral lesions or multifocal lesions, PEM had sensitivity of 85% (34/40) and specificity of 74%, (20/27) compared to MRI's sensitivity of 98% (39/40) and specificity of 48% (13/27) [p = 0.074, for sensitivity; p = 0.096 for specificity] PEM is a good alternative to MRI as a presurgical breast imaging option and its performance characteristics are not affected by patient menopausal/hormonal status or breast density.

The physical and empirical basis for a specific clear-air turbulence risk index

NASA Technical Reports Server (NTRS)

Keller, J. L.

1985-01-01

An improved operational CAT detection and forecasting technique is developed and detailed. This technique is the specific clear air turbulence risk (SCATR) index. This index shows some promising results. The improvements seen using hand analyzed data, as a result of the more realistic representation of the vertical shear of the horizontal wind, are also realized in the data analysis used in the PROFS/CWP application. The SCATR index should improve as database enhancements such as profiler and VAS satellite data, which increase the resolution in space and time, are brought into even more sophisticated objective analysis schemes.

The Index Medicus: Why It Works and When It Doesn't *

PubMed Central

Jackson, Mary F.

1966-01-01

A user study of the Index Medicus done at the Walter Reed Army Medical Center included responses from a group of sixty researchers, clinicians, residents, and interns. An analysis of the questionnaire shows that, while all respondents use the Index Medicus, most use it to search for a specific subject or a specific author reference. Comments received were critical of the delay from the time of journal publication until the appearance of its citation in Index Medicus. Suggestions were offered concerning the type of publication most of the respondents would prefer. PMID:5921472

An innovative index for evaluating water quality in streams.

PubMed

Said, Ahmend; Stevens, David K; Sehlke, Gerald

2004-09-01

A water quality index expressed as a single number is developed to describe overall water quality conditions using multiple water quality variables. The index consists of water quality variables: dissolved oxygen, specific conductivity, turbidity, total phosphorus, and fecal coliform. The objectives of this study were to describe the preexisting indices and to define a new water quality index that has advantages over these indices. The new index was applied to the Big Lost River Watershed in Idaho, and the results gave a quantitative picture for the water quality situation. If the new water quality index for the impaired water is less than a certain number, remediation-likely in the form of total maximum daily loads or changing the management practices-may be needed. The index can be used to assess water quality for general beneficial uses. Nevertheless, the index cannot be used in making regulatory decisions, indicate water quality for specific beneficial uses, or indicate contamination from trace metals, organic contaminants, and toxic substances.

Performance-Based Specifications of Workability Characteristics of Prestressed, Precast Self-Consolidating Concrete-A North American Prospective.

PubMed

Long, Wu-Jian; Khayat, Kamal Henri; Lemieux, Guillaume; Hwang, Soo-Duck; Han, Ning-Xu

2014-03-27

Adequate selection of material constituents and test methods are necessary for workability specifications and performance of hardened concrete. An experimental program was performed to evaluate the suitability of various test methods for workability assessment and to propose performance specifications of prestressed concrete. In total, 33 self-consolidating concrete (SCC) mixtures made with various mixture proportioning parameters, including maximum size and type of aggregate, type and content of binder, and w/cm were evaluated. Correlations among various test results used in evaluating the workability responses are established. It is recommended that SCC should have slump flow values of 635-760 mm. To ensure proper filling capacity greater than 80%, such concrete should have a passing ability that corresponds to L-box blocking ratio (h₂/h₁) ≥ 0.5, J-Ring flow of 570-685 mm, slump flow minus J-Ring flow diameter ≤75 mm. Moreover, Stable SCC should develop a column segregation index lower than 5%, and rate of settlement at 30 min of 0.27%/h for SCC proportioned with 12.5 or 9.5 mm MSA. It is recommended that SCC should have a plastic viscosity of 100-225 Pa·s and 100-400 Pa·s for concrete made with crushed aggregate and gravel, respectively, to ensure proper workability.

Metal-Air Batteries: (Latest citations from the Aerospace Database)

NASA Technical Reports Server (NTRS)

1997-01-01

The bibliography contains citations concerning applications of metal-air batteries. Topics include systems that possess different practical energy densities at specific powers. Coverage includes the operation of air electrodes at different densities and performance results. The systems are used in electric vehicles as a cost-effective method to achieve reliability and efficiency. Zinc-air batteries are covered more thoroughly in a separate bibliography. (Contains 50-250 citations and includes a subject term index and title list.)

Assessment of insulin resistance in lean women with polycystic ovary syndrome.

PubMed

Morciano, Andrea; Romani, Federica; Sagnella, Francesca; Scarinci, Elisa; Palla, Carola; Moro, Francesca; Tropea, Anna; Policola, Caterina; Della Casa, Silvia; Guido, Maurizio; Lanzone, Antonio; Apa, Rosanna

2014-07-01

To develop and validate a specific simple measure of insulin sensitivity using oral glucose tolerance test (OGTT) values for lean polycystic ovary syndrome (PCOS) women. Retrospective study. Gynecologic Outpatient Clinic of University Hospital, affiliated with Unit of Gynecologic Endocrinology. Totals of 201 lean and 198 overweight/obese (ov-ob) nondiabetic PCOS patients were retrospectively selected. None. All patients underwent OGTT, euglycemic-hyperinsulinemic clamp, and androgenic and biochemical assays. The predictive performance of each insulin resistance (IR) index was analyzed with the use of receiver operating characteristic (ROC) curves. Higher correlation coefficients with clamp studies were obtained with the Belfiore Area (RS=0.579) and the homeostasis-model assessment (HOMA)-M120 (RS=-0.576) in lean PCOS patients and with the Sib (RS=0.697) in ov-ob PCOS patients. The best predictive index of IR in lean PCOS was a HOMA-M120 value of ≥12.8 or more (area under the ROC curve [AUC] 92.4%). In the ov-ob PCOS population, the best predictive performance was obtained by a Sib of ≤10.2 or less (AUC 85.7%). IR should be assessed in all PCOS women, both lean and ov-ob subjects. The HOMA-M120 resulted as a very simple tool, validated specifically for the lean PCOS woman whose cardiometabolic impairment is more frequently misunderstood. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Web image retrieval using an effective topic and content-based technique

NASA Astrophysics Data System (ADS)

Lee, Ching-Cheng; Prabhakara, Rashmi

2005-03-01

There has been an exponential growth in the amount of image data that is available on the World Wide Web since the early development of Internet. With such a large amount of information and image available and its usefulness, an effective image retrieval system is thus greatly needed. In this paper, we present an effective approach with both image matching and indexing techniques that improvise on existing integrated image retrieval methods. This technique follows a two-phase approach, integrating query by topic and query by example specification methods. In the first phase, The topic-based image retrieval is performed by using an improved text information retrieval (IR) technique that makes use of the structured format of HTML documents. This technique consists of a focused crawler that not only provides for the user to enter the keyword for the topic-based search but also, the scope in which the user wants to find the images. In the second phase, we use query by example specification to perform a low-level content-based image match in order to retrieve smaller and relatively closer results of the example image. From this, information related to the image feature is automatically extracted from the query image. The main objective of our approach is to develop a functional image search and indexing technique and to demonstrate that better retrieval results can be achieved.

Adaptive model of the aging emmetropic eye and its changes with accommodation.

PubMed

Navarro, Rafael

2014-11-20

A general schematic model of the optical system of the emmetropic human eye is proposed, capable of adapting to changes with age and accommodation through adjustment of the optical surfaces and the internal gradient index structure of the lens. The specific models of the cornea and lens consist of minor generalizations of previous work by assuming them to be the sum of a biconic plus three higher order Zernike modes. The internal gradient index distribution adapts to the external shape so that the analytical expression is invariant with the changes with age and accommodation. The model also includes tips, tilts, and decentrations of the surfaces according to experimental findings. The specific parameters of these models are either constants or functions of age and/or accommodation. The model is polychromatic, and its optical performance was evaluated along the keratometric axis. Chromatic aberrations (longitudinal and transverse), astigmatism, coma, trefoil, and spherical aberration show good agreement with experimental averages. The change of these aberrations as a function of age or accommodation is also consistent with experimental findings (except for trefoil in eyes older than 50 years). This means that the average structure seems to predict the average performance. Nevertheless, the present model is too schematic to account for other higher order aberrations, such as tetrafoil, also present in real eyes. © 2014 ARVO.

Performance characteristics of the PTSD Checklist in retired firefighters exposed to the World Trade Center disaster.

PubMed

Chiu, Sydney; Webber, Mayris P; Zeig-Owens, Rachel; Gustave, Jackson; Lee, Roy; Kelly, Kerry J; Rizzotto, Linda; McWilliams, Rita; Schorr, John K; North, Carol S; Prezant, David J

2011-05-01

Since the World Trade Center (WTC) attacks on September 11, 2001, the Fire Department, City of New York Monitoring Program has provided physical and mental health screening services to rescue/recovery workers. This study evaluated performance of the self-report PTSD Checklist (PCL) as a screening tool for risk of posttraumatic stress disorder (PTSD) in firefighters who worked at Ground Zero, compared with the interviewer-administered Diagnostic Interview Schedule (DIS). From December 2005 to July 2007, all retired firefighter enrollees completed the PCL and DIS on the same day. Sensitivity, specificity, receiver operating characteristic (ROC) curves, and Youden index (J) were used to assess properties of the PCL and to identify an optimum cutoff score. Six percent of 1,915 retired male firefighters were diagnosed with PTSD using the DIS to assess DSM-IV criteria. Depending on the PCL cutoff, the prevalence of elevated risk relative to DSM-IV criteria varied from 16% to 22%. Youden index identified an optimal cutoff score of 39, in contrast with the frequently recommended cutoff of 44. At 39, PCL sensitivity was 0.85, specificity was 0.82, and the area under the ROC curve was 0.91 relative to DIS PTSD diagnosis. This is the first study to validate the PCL in retired firefighters and determine the optimal cutoff score to maximize opportunities for PTSD diagnosis and treatment.

Patient safety and systematic reviews: finding papers indexed in MEDLINE, EMBASE and CINAHL.

PubMed

Tanon, A A; Champagne, F; Contandriopoulos, A-P; Pomey, M-P; Vadeboncoeur, A; Nguyen, H

2010-10-01

To develop search strategies for identifying papers on patient safety in MEDLINE, EMBASE and CINAHL. Six journals were electronically searched for papers on patient safety published between 2000 and 2006. Identified papers were divided into two gold standards: one to build and the other to validate the search strategies. Candidate terms for strategy construction were identified using a word frequency analysis of titles, abstracts and keywords used to index the papers in the databases. Searches were run for each one of the selected terms independently in every database. Sensitivity, precision and specificity were calculated for each candidate term. Terms with sensitivity greater than 10% were combined to form the final strategies. The search strategies developed were run against the validation gold standard to assess their performance. A final step in the validation process was to compare the performance of each strategy to those of other strategies found in the literature. We developed strategies for all three databases that were highly sensitive (range 95%-100%), precise (range 40%-60%) and balanced (the product of sensitivity and precision being in the range of 30%-40%). The strategies were very specific and outperformed those found in the literature. The strategies we developed can meet the needs of users aiming to maximise either sensitivity or precision, or seeking a reasonable compromise between sensitivity and precision, when searching for papers on patient safety in MEDLINE, EMBASE or CINAHL.

A Novel Approach to Prediction of Mild Obstructive Sleep Disordered Breathing in a Population-Based Sample: The Sleep Heart Health Study

PubMed Central

Caffo, Brian; Diener-West, Marie; Punjabi, Naresh M.; Samet, Jonathan

2010-01-01

This manuscript considers a data-mining approach for the prediction of mild obstructive sleep disordered breathing, defined as an elevated respiratory disturbance index (RDI), in 5,530 participants in a community-based study, the Sleep Heart Health Study. The prediction algorithm was built using modern ensemble learning algorithms, boosting in specific, which allowed for assessing potential high-dimensional interactions between predictor variables or classifiers. To evaluate the performance of the algorithm, the data were split into training and validation sets for varying thresholds for predicting the probability of a high RDI (≥ 7 events per hour in the given results). Based on a moderate classification threshold from the boosting algorithm, the estimated post-test odds of a high RDI were 2.20 times higher than the pre-test odds given a positive test, while the corresponding post-test odds were decreased by 52% given a negative test (sensitivity and specificity of 0.66 and 0.70, respectively). In rank order, the following variables had the largest impact on prediction performance: neck circumference, body mass index, age, snoring frequency, waist circumference, and snoring loudness. Citation: Caffo B; Diener-West M; Punjabi NM; Samet J. A novel approach to prediction of mild obstructive sleep disordered breathing in a population-based sample: the Sleep Heart Health Study. SLEEP 2010;33(12):1641-1648. PMID:21120126

Diagnostic performance of body mass index using the Western Pacific Regional Office of World Health Organization reference standards for body fat percentage.

PubMed

Yoon, Jong Lull; Cho, Jung Jin; Park, Kyung Mi; Noh, Hye Mi; Park, Yong Soon

2015-02-01

Associations between body mass index (BMI), body fat percentage (BF%), and health risks differ between Asian and European populations. BMI is commonly used to diagnose obesity; however, its accuracy in detecting adiposity in Koreans is unknown. The present cross-sectional study aimed at assessing the accuracy of BMI in determining BF%-defined obesity in 6,017 subjects (age 20-69 yr, 43.6% men) from the 2009 Korean National Health and Nutrition Examination Survey. We assessed the diagnostic performance of BMI using the Western Pacific Regional Office of World Health Organization reference standard for BF%-defined obesity by sex and age and identified the optimal BMI cut-off for BF%-defined obesity using receiver operating characteristic curve analysis. BMI-defined obesity (≥25 kg/m(2)) was observed in 38.7% of men and 28.1% of women, with a high specificity (89%, men; 84%, women) but poor sensitivity (56%, men; 72% women) for BF%-defined obesity (25.2%, men; 31.1%, women). The optimal BMI cut-off (24.2 kg/m(2)) had 78% sensitivity and 71% specificity. BMI demonstrated limited diagnostic accuracy for adiposity in Korea. There was a -1.3 kg/m(2) difference in optimal BMI cut-offs between Korea and America, smaller than the 5-unit difference between the Western Pacific Regional Office and global World Health Organization obesity criteria.

Model for End-Stage Liver Disease, Model for Liver Transplantation Survival and Donor Risk Index as predictive models of survival after liver transplantation in 1,006 patients.

PubMed

Aranzana, Elisa Maria de Camargo; Coppini, Adriana Zuolo; Ribeiro, Maurício Alves; Massarollo, Paulo Celso Bosco; Szutan, Luiz Arnaldo; Ferreira, Fabio Gonçalves

2015-06-01

Liver transplantation has not increased with the number of patients requiring this treatment, increasing deaths among those on the waiting list. Models predicting post-transplantation survival, including the Model for Liver Transplantation Survival and the Donor Risk Index, have been created. Our aim was to compare the performance of the Model for End-Stage Liver Disease, the Model for Liver Transplantation Survival and the Donor Risk Index as prognostic models for survival after liver transplantation. We retrospectively analyzed the data from 1,270 patients who received a liver transplant from a deceased donor in the state of São Paulo, Brazil, between July 2006 and July 2009. All data obtained from the Health Department of the State of São Paulo at the 15 registered transplant centers were analyzed. Patients younger than 13 years of age or with acute liver failure were excluded. The majority of the recipients had Child-Pugh class B or C cirrhosis (63.5%). Among the 1,006 patients included, 274 (27%) died. Univariate survival analysis using a Cox proportional hazards model showed hazard ratios of 1.02 and 1.43 for the Model for End-Stage Liver Disease and the Model for Liver Transplantation Survival, respectively (p<0.001). The areas under the ROC curve for the Donor Risk Index were always less than 0.5, whereas those for the Model for End-Stage Liver Disease and the Model for Liver Transplantation Survival were significantly greater than 0.5 (p<0.001). The cutoff values for the Model for End-Stage Liver Disease (≥29.5; sensitivity: 39.1%; specificity: 75.4%) and the Model for Liver Transplantation Survival (≥1.9; sensitivity 63.9%, specificity 54.5%), which were calculated using data available before liver transplantation, were good predictors of survival after liver transplantation (p<0.001). The Model for Liver Transplantation Survival displayed similar death prediction performance to that of the Model for End-Stage Liver Disease. A simpler model involving fewer variables, such as the Model for End-Stage Liver Disease, is preferred over a complex model involving more variables, such as the Model for Liver Transplantation Survival. The Donor Risk Index had no significance in post-transplantation survival in our patients.

Intentional and automatic numerical processing as predictors of mathematical abilities in primary school children

PubMed Central

Pina, Violeta; Castillo, Alejandro; Cohen Kadosh, Roi; Fuentes, Luis J.

2015-01-01

Previous studies have suggested that numerical processing relates to mathematical performance, but it seems that such relationship is more evident for intentional than for automatic numerical processing. In the present study we assessed the relationship between the two types of numerical processing and specific mathematical abilities in a sample of 109 children in grades 1–6. Participants were tested in an ample range of mathematical tests and also performed both a numerical and a size comparison task. The results showed that numerical processing related to mathematical performance only when inhibitory control was involved in the comparison tasks. Concretely, we found that intentional numerical processing, as indexed by the numerical distance effect in the numerical comparison task, was related to mathematical reasoning skills only when the task-irrelevant dimension (the physical size) was incongruent; whereas automatic numerical processing, indexed by the congruency effect in the size comparison task, was related to mathematical calculation skills only when digits were separated by small distance. The observed double dissociation highlights the relevance of both intentional and automatic numerical processing in mathematical skills, but when inhibitory control is also involved. PMID:25873909

Study of 3D printing method for GRIN micro-optics devices

NASA Astrophysics Data System (ADS)

Wang, P. J.; Yeh, J. A.; Hsu, W. Y.; Cheng, Y. C.; Lee, W.; Wu, N. H.; Wu, C. Y.

2016-03-01

Conventional optical elements are based on either refractive or reflective optics theory to fulfill the design specifications via optics performance data. In refractive optical lenses, the refractive index of materials and radius of curvature of element surfaces determine the optical power and wavefront aberrations so that optical performance can be further optimized iteratively. Although gradient index (GRIN) phenomenon in optical materials is well studied for more than a half century, the optics theory in lens design via GRIN materials is still yet to be comprehensively investigated before realistic GRIN lenses are manufactured. In this paper, 3D printing method for manufacture of micro-optics devices with special features has been studied based on methods reported in the literatures. Due to the additive nature of the method, GRIN lenses in micro-optics devices seem to be readily achievable if a design methodology is available. First, derivation of ray-tracing formulae is introduced for all possible structures in GRIN lenses. Optics simulation program is employed for characterization of GRIN lenses with performance data given by aberration coefficients in Zernike polynomial. Finally, a proposed structure of 3D printing machine is described with conceptual illustration.

Radial shock wave treatment alone is less efficient than radial shock wave treatment combined with tissue-specific plantar fascia-stretching in patients with chronic plantar heel pain.

PubMed

Rompe, Jan D; Furia, John; Cacchio, Angelo; Schmitz, Christoph; Maffulli, Nicola

2015-12-01

Whether shock wave therapy or shock wave therapy combined with plantar fascia-specific stretching is more efficient in treating chronic plantar heel pain remains unclear. The aim of the study was to test the null hypothesis of no difference of these two forms of management for patients who had unilateral plantar fasciopathy for a minimum duration of twelve months and which had failed at least three other forms of treatment. One hundred and fifty-two patients with chronic plantar fasciopathy were assigned to receive repetitive low-energy radial shock-wave therapy without local anesthesia, administered weekly for three weeks (Group 1, n = 73) or to receive the identical shock wave treatment and to perform an eight-week plantar fascia-specific stretching program (Group 2, n = 79). All patients completed the nine-item pain subscale of the validated Foot Function Index and a subject-relevant outcome questionnaire. Patients were evaluated at baseline, and at two, four, and twenty-four months after baseline. The primary outcome measures were a mean change in the Foot Function Index sum score at two months after baseline, a mean change in item 2 (pain during the first steps of walking in the morning) on this Index, and satisfaction with treatment. No difference in mean age, sex, weight or duration of symptoms was found between the groups at baseline. At two months after baseline, the Foot Function Index sum score showed significantly greater changes for the patients managed with shock-wave therapy plus plantar fascia-specific stretching than those managed with shock-wave therapy alone (p < 0.001), as well as individually for item 2 (p < 0.001). Twenty-four patients in Group 1 (32%) versus forty-seven patients in Group 2 (59%) were satisfied with the treatment (p < 0.001). Significant differences persisted at four months, but not at twenty-four months. A program of manual stretching exercises specific to the plantar fascia in combination with repetitive low-energy radial shock-wave therapy is more efficient than repetitive low-energy radial shock-wave therapy alone for the treatment of chronic symptoms of proximal plantar fasciopathy. Copyright © 2015 IJS Publishing Group Limited. Published by Elsevier Ltd. All rights reserved.

Computer-Based Indexing on a Small Scale: Bibliography.

ERIC Educational Resources Information Center

Douglas, Kimberly; Wismer, Don

The 131 references on small scale computer-based indexing cited in this bibliography are subdivided as follows: general, general (computer), index structure, microforms, specific systems, KWIC KWAC KWOC, and thesauri. (RAA)

Age of majority assessment in Dutch individuals based on Cameriere's third molar maturity index.

PubMed

Boyacıoğlu Doğru, Hatice; Gulsahi, Ayşe; Çehreli, Sevi Burçak; Galić, Ivan; van der Stelt, Paul; Cameriere, Roberto

2018-01-01

Radiological examination of the third molar is done in living individuals for estimation of chronological age, especially in the late adolescence. The aim of this study was to assess the application of Cameriere's third molar maturity index (I 3M ) to determine whether an individual is 18 years or older (adult) or younger than 18 years (minor) in a sample of Dutch individuals. The sample consisted of panoramic images of 360 individuals aged between 14 and 22 years old. Three observers performed the measurements. Gender was not statistically significant in discriminating adults and minors. The highest value of the Youden index of the receiver operating curve analysis was for the value of I 3M <0.08 in discriminating individuals as minor or adult. The specificity (Sp) and sensitivity (Se) results for females were 96.3% and 72.7% respectively. The Sp and Se for males were 95.0% and 84.0% respectively. The probabilities of correctly classified individuals were 83.3% and 88.9%, and Bayes post-test probability was 96.3% and 95.7% in females and males respectively. Obtained results showed that the specific cut-off point of I 3M <0.08 may be a useful and reliable method for adult age assessment in a Dutch population. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of Neutrophil-to-Lymphocyte Ratio and Platelet-to-Lymphocyte Ratio in Atopic Dermatitis Patients

PubMed Central

Jiang, Ying; Ma, Wencong

2017-01-01

Background To develop new strategies for identifying atopic dermatitis patients, a better understanding of the signs for chronic inflammatory status is needed. This study was designed to investigate whether neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) are related to the severity of atopic dermatitis (AD) assessed by the Scoring Atopic Dermatitis (SCORAD) index. Material/Methods A retrospective study involving 80 AD patients and 45 healthy control subjects was performed. NLR, PLR, and the number of peripheral blood eosinophils were compared between AD patients and healthy controls, and correlations between these indexes and clinical characteristics were analyzed. Results NLR, PLR, and eosinophils in AD patients were all significantly higher than in healthy individuals. Among AD patients, NLR (p<0.001) and PLR (p<0.001), as contrasted with eosinophils (p=0.146), were correlated positively with SCORAD index. Additionally, an NLR level of 1.75 was determined as the predictive cut-off value of severe AD (SCORAD ≥51) (sensitivity 94.7%, specificity 58.6%, the area under the receiver-operating characteristic curve (AUROC) 0.778, p=0.001). For eosinophils, the sensitivity and specificity were 78.9% and 62.1%, respectively, and the AUROC was only 0.685 (p=0.032) in predicting high SCORAD. Conclusions NLR and PLR reflect inflammatory response and disease severity in AD patients. PMID:28306706

Measurement of thermo-optic properties of Y3Al5O12, Lu3Al5O12, YAIO3, LiYF4, LiLuF4, BaY2F8, KGd(WO4)2, and KY(WO4)2 laser crystals in the 80-300 K temperature range

NASA Astrophysics Data System (ADS)

Aggarwal, R. L.; Ripin, D. J.; Ochoa, J. R.; Fan, T. Y.

2005-11-01

Thermo-optic materials properties of laser host materials have been measured to enable solid-state laser performance modeling. The thermo-optic properties include thermal diffusivity (β), specific heat at constant pressure (Cp), thermal conductivity (κ), coefficient of thermal expansion (α), thermal coefficient of the optical path length (γ) equal to (dO/dT)/L, and thermal coefficient of refractive index (dn/dT) at 1064nm; O denotes the optical path length, which is equal to the product of the refractive index (n) and sample length (L). Thermal diffusivity and specific heat were measured using laser-flash method. Thermal conductivity was deduced using measured values of β, Cp, and the density (ρ ). Thermal expansion was measured using a Michelson laser interferometer. Thermal coefficient of the optical path length was measured at 1064nm, using interference between light reflected from the front and rear facets of the sample. Thermal coefficient of the refractive index was determined, using the measured values of γ, α, and n. β and κ of Y3Al5O12, YAIO3, and LiYF4 were found to decrease, as expected, upon doping with Yb.

Database Performance Monitoring for the Photovoltaic Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klise, Katherine A.

The Database Performance Monitoring (DPM) software (copyright in processes) is being developed at Sandia National Laboratories to perform quality control analysis on time series data. The software loads time indexed databases (currently csv format), performs a series of quality control tests defined by the user, and creates reports which include summary statistics, tables, and graphics. DPM can be setup to run on an automated schedule defined by the user. For example, the software can be run once per day to analyze data collected on the previous day. HTML formatted reports can be sent via email or hosted on a website.more » To compare performance of several databases, summary statistics and graphics can be gathered in a dashboard view which links to detailed reporting information for each database. The software can be customized for specific applications.« less

A general theory of multimetric indices and their properties

USGS Publications Warehouse

Schoolmaster, Donald R.; Grace, James B.; Schweiger, E. William

2012-01-01

1. Stewardship of biological and ecological resources requires the ability to make integrative assessments of ecological integrity. One of the emerging methods for making such integrative assessments is multimetric indices (MMIs). These indices synthesize data, often from multiple levels of biological organization, with the goal of deriving a single index that reflects the overall effects of human disturbance. Despite the widespread use of MMIs, there is uncertainty about why this approach can be effective. An understanding of MMIs requires a quantitative theory that illustrates how the properties of candidate metrics relates to MMIs generated from those metrics. 2. We present the initial basis for such a theory by deriving the general mathematical characteristics of MMIs assembled from metrics. We then use the theory to derive quantitative answers to the following questions: Is there an optimal number of metrics to comprise an index? How does covariance among metrics affect the performance of the index derived from those metrics? And what are the criteria to decide whether a given metric will improve the performance of an index? 3. We find that the optimal number of metrics to be included in an index depends on the theoretical distribution of signal of the disturbance gradient contained in each metric. For example, if the rank-ordered parameters of a metric-disturbance regression can be described by a monotonically decreasing function, then an optimum number of metrics exists and can often be derived analytically. We derive the conditions by which adding a given metric can be expected to improve an index. 4. We find that the criterion defining such conditions depends nonlinearly of the signal of the disturbance gradient, the noise (error) of the metric and the correlation of the metric errors. Importantly, we find that correlation among metric errors increases the signal required for the metric to improve the index. 5. The theoretical framework presented in this study provides the basis for understanding the properties of MMIs. It can also be useful throughout the index construction process. Specifically, it can be used to aid understanding of the benefits and limitations of combining metrics into indices; it can inform selection/collection of candidate metrics; and it can be used directly as a decision aid in effective index construction.

Development, Validation, and Assessment of an Ischemic Stroke or Transient Ischemic Attack-Specific Prediction Tool for Obstructive Sleep Apnea.

PubMed

Sico, Jason J; Yaggi, H Klar; Ofner, Susan; Concato, John; Austin, Charles; Ferguson, Jared; Qin, Li; Tobias, Lauren; Taylor, Stanley; Vaz Fragoso, Carlos A; McLain, Vincent; Williams, Linda S; Bravata, Dawn M

2017-08-01

Screening instruments for obstructive sleep apnea (OSA), as used routinely to guide clinicians regarding patient referral for polysomnography (PSG), rely heavily on symptomatology. We sought to develop and validate a cerebrovascular disease-specific OSA prediction model less reliant on symptomatology, and to compare its performance with commonly used screening instruments within a population with ischemic stroke or transient ischemic attack (TIA). Using data on demographic factors, anthropometric measurements, medical history, stroke severity, sleep questionnaires, and PSG from 2 independently derived, multisite, randomized trials that enrolled patients with stroke or TIA, we developed and validated a model to predict the presence of OSA (i.e., Apnea-Hypopnea Index ≥5 events per hour). Model performance was compared with that of the Berlin Questionnaire, Epworth Sleepiness Scale (ESS), the Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender instrument, and the Sleep Apnea Clinical Score. The new SLEEP Inventory (Sex, Left heart failure, ESS, Enlarged neck, weight [in Pounds], Insulin resistance/diabetes, and National Institutes of Health Stroke Scale) performed modestly better than other instruments in identifying patients with OSA, showing reasonable discrimination in the development (c-statistic .732) and validation (c-statistic .731) study populations, and having the highest negative predictive value of all in struments. Clinicians should be aware of these limitations in OSA screening instruments when making decisions about referral for PSG. The high negative predictive value of the SLEEP INventory may be useful in determining and prioritizing patients with stroke or TIA least in need of overnight PSG. Published by Elsevier Inc.

Selection of suitable hand gestures for reliable myoelectric human computer interface.

PubMed

Castro, Maria Claudia F; Arjunan, Sridhar P; Kumar, Dinesh K

2015-04-09

Myoelectric controlled prosthetic hand requires machine based identification of hand gestures using surface electromyogram (sEMG) recorded from the forearm muscles. This study has observed that a sub-set of the hand gestures have to be selected for an accurate automated hand gesture recognition, and reports a method to select these gestures to maximize the sensitivity and specificity. Experiments were conducted where sEMG was recorded from the muscles of the forearm while subjects performed hand gestures and then was classified off-line. The performances of ten gestures were ranked using the proposed Positive-Negative Performance Measurement Index (PNM), generated by a series of confusion matrices. When using all the ten gestures, the sensitivity and specificity was 80.0% and 97.8%. After ranking the gestures using the PNM, six gestures were selected and these gave sensitivity and specificity greater than 95% (96.5% and 99.3%); Hand open, Hand close, Little finger flexion, Ring finger flexion, Middle finger flexion and Thumb flexion. This work has shown that reliable myoelectric based human computer interface systems require careful selection of the gestures that have to be recognized and without such selection, the reliability is poor.

48 CFR 11.204 - Solicitation provisions and contract clauses.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Commercial Item Descriptions, FPMR Part 101-29, in solicitations that cite specifications listed in the Index... Acquisition Streamlining and Standardization Information System (ASSIST), in solicitations that cite..., in solicitations that cite specifications that are not listed in the Index and are not furnished with...

The NLM Indexing Initiative.

PubMed Central

Aronson, A. R.; Bodenreider, O.; Chang, H. F.; Humphrey, S. M.; Mork, J. G.; Nelson, S. J.; Rindflesch, T. C.; Wilbur, W. J.

2000-01-01

The objective of NLM's Indexing Initiative (IND) is to investigate methods whereby automated indexing methods partially or completely substitute for current indexing practices. The project will be considered a success if methods can be designed and implemented that result in retrieval performance that is equal to or better than the retrieval performance of systems based principally on humanly assigned index terms. We describe the current state of the project and discuss our plans for the future. PMID:11079836

Evaluation of Sub Query Performance in SQL Server

NASA Astrophysics Data System (ADS)

Oktavia, Tanty; Sujarwo, Surya

2014-03-01

The paper explores several sub query methods used in a query and their impact on the query performance. The study uses experimental approach to evaluate the performance of each sub query methods combined with indexing strategy. The sub query methods consist of in, exists, relational operator and relational operator combined with top operator. The experimental shows that using relational operator combined with indexing strategy in sub query has greater performance compared with using same method without indexing strategy and also other methods. In summary, for application that emphasized on the performance of retrieving data from database, it better to use relational operator combined with indexing strategy. This study is done on Microsoft SQL Server 2012.

Financing Higher Standards in Public Education: The Importance of Accounting for Educational Costs. Policy Brief, No. 10.

ERIC Educational Resources Information Center

Duncombe, William; Yinger, John

This policy brief explains why performance focus and educational cost indexes must go hand in hand, discusses alternative methods for estimating educational cost indexes, and shows how these costs indexes can be incorporated into a performance-based state aid program. A shift to educational performance standards, whether these standards are…

Is Kyphosis Related to Mobility, Balance and Disability?

PubMed Central

Eum, Regina; Leveille, Suzanne G.; Kiely, Dan K.; Kiel, Douglas P.; Samelson, Elizabeth J.; Bean, Jonathan F.

2013-01-01

Objective To determine the association of increased kyphosis with declines in mobility, balance and disability among community-living older adults. Design 18-month follow-up visit data from 2006–2009 for 620 participants from the population-based MOBILIZE Boston Study of older adults was used. Cross-sectional multivariable regression analyses were performed to assess the relationship between kyphosis (measured using the kyphosis index (KI)) and measures of mobility performance (Short Physical Performance Battery (SPPB)), balance (Berg Balance Score (BBS)) and disability (self-reported difficulty walking a quarter-mile or climbing a flight of stairs). We then evaluated men and women separately. Adjustment variables included demographic factors (age, gender, race, education), body-mass index, self-rated health, comorbidities (heart disease, diabetes, stroke, depressive symptoms), back pain, knee pain and falls self-efficacy. Results After full adjustment, greater KI was associated with lower SPPB scores (adj. β = −0.08, p = 0.01), but not BBS (adj. β = −0.09, p = 0.23) or self-reported disability (adj. β = 1.00, 95% CI, 0.93 –1.06). In gender-specific analyses, KI was only associated with SPPB in women. Conclusions Greater kyphosis is associated with poorer mobility performance, but not balance or self-reported disability. This association with SPPB was only observed among women. Mechanisms by which increased kyphosis influence physical performance should be explored prospectively. PMID:23636086

Discrimination in measures of knowledge monitoring accuracy

PubMed Central

Was, Christopher A.

2014-01-01

Knowledge monitoring predicts academic outcomes in many contexts. However, measures of knowledge monitoring accuracy are often incomplete. In the current study, a measure of students’ ability to discriminate known from unknown information as a component of knowledge monitoring was considered. Undergraduate students’ knowledge monitoring accuracy was assessed and used to predict final exam scores in a specific course. It was found that gamma, a measure commonly used as the measure of knowledge monitoring accuracy, accounted for a small, but significant amount of variance in academic performance whereas the discrimination and bias indexes combined to account for a greater amount of variance in academic performance. PMID:25339979

Uptake Index of 123I-metaiodobenzylguanidine Myocardial Scintigraphy for Diagnosing Lewy Body Disease

PubMed Central

Kamiya, Yoshito; Ota, Satoru; Okumiya, Shintaro; Yamashita, Kosuke; Takaki, Akihiro; Ito, Shigeki

2017-01-01

Objective(s): Iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy has been used to evaluate cardiac sympathetic denervation in Lewy body disease (LBD), including Parkinson’s disease (PD) and dementia with Lewy bodies (DLB). The heart-to-mediastinum ratio (H/M) in PD and DLB is significantly lower than that in Parkinson’s plus syndromes and Alzheimer’s disease. Although this ratio is useful for distinguishing LBD from non-LBD, it fluctuates depending on the system performance of the gamma cameras. Therefore, a new, simple quantification method using 123I-MIBG uptake analysis is required for clinical study. The purpose of this study was to develop a new uptake index with a simple protocol to determine 123I-MIBG uptake on planar images. Methods: The 123I-MIBG input function was obtained from the input counts of the pulmonary artery (PA), which were assessed by analyzing the PA time-activity curves. The heart region of interest used for determining the H/M was used for calculating the uptake index, which was obtained by dividing the heart count by the input count. Results: Forty-eight patients underwent 123I-MIBG chest angiography and planar imaging, after clinical feature assessment and tracer injection. The H/M and 123I-MIBG uptake index were calculated and correlated with clinical features. Values for LBD were significantly lower than those for non-LBD in all analyses (P<0.001). The overlapping ranges between non-LBD and LBD were 2.15 to 2.49 in the H/M method, and 1.04 to 1.22% in the uptake index method. The diagnostic accuracy of the uptake index (area under the curve (AUC), 0.98; sensitivity, 96%; specificity, 91%; positive predictive value (PPV), 90%; negative predictive value (NPV), 93%; and accuracy, 92%) was approximately equal to that of the H/M (AUC, 0.95; sensitivity, 93%; specificity, 91%; PPV, 90%; NPV, 93%; and accuracy, 92%) for discriminating patients with LBD and non-LBD. Conclusion: A simple uptake index method was developed using 123I-MIBG planar imaging and the input counts determined by analyzing chest radioisotope angiography images of the PA. The diagnostic accuracy of the uptake index was approximately equal to that of the H/M for discriminating patients with LBD and non-LBD. PMID:28840137

Multi- and monofractal indices of short-term heart rate variability.

PubMed

Fischer, R; Akay, M; Castiglioni, P; Di Rienzo, M

2003-09-01

Indices of heart rate variability (HRV) based on fractal signal models have recently been shown to possess value as predictors of mortality in specific patient populations. To develop more powerful clinical indices of HRV based on a fractal signal model, the study investigated two HRV indices based on a monofractal signal model called fractional Brownian motion and an index based on a multifractal signal model called multifractional Brownian motion. The performance of the indices was compared with an HRV index in common clinical use. To compare the indices, 18 normal subjects were subjected to postural changes, and the indices were compared on their ability to respond to the resulting autonomic events in HRV recordings. The magnitude of the response to postural change (normalised by the measurement variability) was assessed by analysis of variance and multiple comparison testing. Four HRV indices were investigated for this study: the standard deviation of all normal R-R intervals; an HRV index commonly used in the clinic; detrended fluctuation analysis, an HRV index found to be the most powerful predictor of mortality in a study of patients with depressed left ventricular function; an HRV index developed using the maximum likelihood estimation (MLE) technique for a monofractal signal model; and an HRV index developed for the analysis of multifractional Brownian motion signals. The HRV index based on the MLE technique was found to respond most strongly to the induced postural changes (95% CI). The magnitude of its response (normalised by the measurement variability) was at least 25% greater than any of the other indices tested.

Developing an Index to Measure Health System Performance: Measurement for Districts of Nepal.

PubMed

Kandel, N; Fric, A; Lamichhane, J

2014-01-01

Various frameworks for measuring health system performance have been proposed and discussed. The scope of using performance indicators are broad, ranging from examining national health system to individual patients at various levels of health system. Development of innovative and easy index is essential to measure multidimensionality of health systems. We used indicators, which also serve as proxy to the set of activities, whose primary goal is to maintain and improve health. We used eleven indicators of MDGs, which represent all dimensions of health to develop index. These indicators are computed with similar methodology that of human development index. We used published data of Nepal for computation of the index for districts of Nepal as an illustration. To validate our finding, we compared the indices of these districts with other development indices of Nepal. An index for each district has been computed from eleven indicators. Then indices are compared with that of human development index, socio-economic and infrastructure development indices and findings has shown the similarity on distribution of districts. Categories of low and high performing districts on health system performance are also having low and high human development, socio-economic, and infrastructure indices respectively. This methodology of computing index from various indicators could assist policy makers and program managers to prioritize activities based on their performance. Validation of the findings with that of other development indicators show that this can be one of the tools, which can assist on assessing health system performance for policy makers, program managers and others.

Cumulative exposure to work-related traumatic events and current post-traumatic stress disorder in New York City's first responders.

PubMed

Geronazzo-Alman, Lupo; Eisenberg, Ruth; Shen, Sa; Duarte, Cristiane S; Musa, George J; Wicks, Judith; Fan, Bin; Doan, Thao; Guffanti, Guia; Bresnahan, Michaeline; Hoven, Christina W

2017-04-01

Cumulative exposure to work-related traumatic events (CE) is a foreseeable risk for psychiatric disorders in first responders (FRs). Our objective was to examine the impact of work-related CE that could serve as predictor of posttraumatic stress disorder (PTSD) and/or depression in FRs. Cross-sectional examination of previous CE and past-month PTSD outcomes and depression in 209 FRs. Logistic (probable PTSD; probable depression) and Poisson regressions (PTSD score) of the outcomes on work-related CE indexes, adjusting for demographic variables. Differences across occupational groups were also examined. Receiver operating characteristic analysis determined the sensitivity and specificity of CE indexes. All indexes were significantly and differently associated with PTSD; associations with depression were non-significant. The index capturing the sheer number of different incidents experienced regardless of frequency ('Variety') showed conceptual, practical and statistical advantages compared to other indexes. In general, the indexes showed poor to fair discrimination accuracy. Work-related CE is specifically associated with PTSD. Focusing on the variety of exposures may be a simple and effective strategy to predict PTSD in FRs. Further research on sensitivity and specificity of exposure indexes, preferably examined prospectively, is needed and could lead to early identification of individuals at risk. Copyright © 2016 Elsevier Inc. All rights reserved.

Multisite Evaluation of APEX for Water Quality: II. Regional Parameterization.

PubMed

Nelson, Nathan O; Baffaut, Claire; Lory, John A; Anomaa Senaviratne, G M M M; Bhandari, Ammar B; Udawatta, Ranjith P; Sweeney, Daniel W; Helmers, Matt J; Van Liew, Mike W; Mallarino, Antonio P; Wortmann, Charles S

2017-11-01

Phosphorus (P) Index assessment requires independent estimates of long-term average annual P loss from fields, representing multiple climatic scenarios, management practices, and landscape positions. Because currently available measured data are insufficient to evaluate P Index performance, calibrated and validated process-based models have been proposed as tools to generate the required data. The objectives of this research were to develop a regional parameterization for the Agricultural Policy Environmental eXtender (APEX) model to estimate edge-of-field runoff, sediment, and P losses in restricted-layer soils of Missouri and Kansas and to assess the performance of this parameterization using monitoring data from multiple sites in this region. Five site-specific calibrated models (SSCM) from within the region were used to develop a regionally calibrated model (RCM), which was further calibrated and validated with measured data. Performance of the RCM was similar to that of the SSCMs for runoff simulation and had Nash-Sutcliffe efficiency (NSE) > 0.72 and absolute percent bias (|PBIAS|) < 18% for both calibration and validation. The RCM could not simulate sediment loss (NSE < 0, |PBIAS| > 90%) and was particularly ineffective at simulating sediment loss from locations with small sediment loads. The RCM had acceptable performance for simulation of total P loss (NSE > 0.74, |PBIAS| < 30%) but underperformed the SSCMs. Total P-loss estimates should be used with caution due to poor simulation of sediment loss. Although we did not attain our goal of a robust regional parameterization of APEX for estimating sediment and total P losses, runoff estimates with the RCM were acceptable for P Index evaluation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Comparison of laboratory tests, ultrasound, or magnetic resonance elastography to detect fibrosis in patients with nonalcoholic fatty liver disease: A meta-analysis.

PubMed

Xiao, Guangqin; Zhu, Sixian; Xiao, Xiao; Yan, Lunan; Yang, Jiayin; Wu, Gang

2017-11-01

Many noninvasive methods for diagnosing liver fibrosis (LF) have been proposed. To determine the best method for diagnosing LF in nonalcoholic fatty liver disease (NAFLD), we conducted a systemic review and meta-analysis to compare the performance of aspartate aminotransferase to platelets ratio index (APRI), fibrosis-4 index (FIB-4), BARD score, NAFLD fibrosis score (NFS), FibroScan, shear wave elastography (SWE), and magnetic resonance elastography (MRE) for diagnosing LF in NAFLD. We compared the sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUROC) of these noninvasive methods for detecting significant fibrosis (SF), advanced fibrosis (AF), and cirrhosis. Heterogeneity was explored using meta-regression. Sixty-four articles with a total of 13,046 NAFLD subjects were included. The overall mean prevalence of SF, AF, and cirrhosis was 45.0%, 24.0%, and 9.4% in NAFLD patients, respectively. With an APRI threshold of 1.0 and 1.5, the sensitivities and specificities were 50.0% and 84.0% and 18.3% and 96.1%, respectively, for AF. With a FIB-4 threshold of 2.67 and 3.25, the sensitivities and specificities were 26.6% and 96.5% and 31.8% and 96.0%, respectively, for AF. The summary sensitivities and specificities of BARD score (threshold of 2), NFS (threshold of -1.455), FibroScan M (threshold of 8.7-9), SWE, and MRE for detecting AF were 0.76 and 0.61, 0.72 and 0.70, 0.87 and 0.79, 0.90 and 0.93, and 0.84 and 0.90, respectively. The summary AUROC values using APRI, FIB-4, BARD score, NFS, FibroScan M probe, XL probe, SWE, and MRE for diagnosing AF were 0.77, 0.84, 0.76, 0.84, 0.88, 0.85, 0.95, and 0.96, respectively. MRE and SWE may have the highest diagnostic accuracy for staging fibrosis in NAFLD patients. Among the four noninvasive simple indexes, NFS and FIB-4 probably offer the best diagnostic performance for detecting AF. (Hepatology 2017;66:1486-1501). © 2017 by the American Association for the Study of Liver Diseases.

Left ventricular hypertrophy index based on a combination of frontal and transverse planes in the ECG and VCG: Diagnostic utility of cardiac vectors

NASA Astrophysics Data System (ADS)

Bonomini, Maria Paula; Juan Ingallina, Fernando; Barone, Valeria; Antonucci, Ricardo; Valentinuzzi, Max; Arini, Pedro David

2016-04-01

The changes that left ventricular hypertrophy (LVH) induces in depolarization and repolarization vectors are well known. We analyzed the performance of the electrocardiographic and vectorcardiographic transverse planes (TP in the ECG and XZ in the VCG) and frontal planes (FP in the ECG and XY in the VCG) to discriminate LVH patients from control subjects. In an age-balanced set of 58 patients, the directions and amplitudes of QRS-complexes and T-wave vectors were studied. The repolarization vector significantly decreased in modulus from controls to LVH in the transverse plane (TP: 0.45±0.17mV vs. 0.24±0.13mV, p<0.0005 XZ: 0.43±0.16mV vs. 0.26±0.11mV, p<0.005) while the depolarization vector significantly changed in angle in the electrocardiographic frontal plane (Controls vs. LVH, FP: 48.24±33.66° vs. 46.84±35.44°, p<0.005, XY: 20.28±35.20° vs. 19.35±12.31°, NS). Several LVH indexes were proposed combining such information in both ECG and VCG spaces. A subset of all those indexes with AUC values greater than 0.7 was further studied. This subset comprised four indexes, with three of them belonging to the ECG space. Two out of the four indexes presented the best ROC curves (AUC values: 0.78 and 0.75, respectively). One index belonged to the ECG space and the other one to the VCG space. Both indexes showed a sensitivity of 86% and a specificity of 70%. In conclusion, the proposed indexes can favorably complement LVH diagnosis

Evaluating the accuracy of the Wechsler Memory Scale-Fourth Edition (WMS-IV) logical memory embedded validity index for detecting invalid test performance.

PubMed

Soble, Jason R; Bain, Kathleen M; Bailey, K Chase; Kirton, Joshua W; Marceaux, Janice C; Critchfield, Edan A; McCoy, Karin J M; O'Rourke, Justin J F

2018-01-08

Embedded performance validity tests (PVTs) allow for continuous assessment of invalid performance throughout neuropsychological test batteries. This study evaluated the utility of the Wechsler Memory Scale-Fourth Edition (WMS-IV) Logical Memory (LM) Recognition score as an embedded PVT using the Advanced Clinical Solutions (ACS) for WAIS-IV/WMS-IV Effort System. This mixed clinical sample was comprised of 97 total participants, 71 of whom were classified as valid and 26 as invalid based on three well-validated, freestanding criterion PVTs. Overall, the LM embedded PVT demonstrated poor concordance with the criterion PVTs and unacceptable psychometric properties using ACS validity base rates (42% sensitivity/79% specificity). Moreover, 15-39% of participants obtained an invalid ACS base rate despite having a normatively-intact age-corrected LM Recognition total score. Receiving operating characteristic curve analysis revealed a Recognition total score cutoff of < 61% correct improved specificity (92%) while sensitivity remained weak (31%). Thus, results indicated the LM Recognition embedded PVT is not appropriate for use from an evidence-based perspective, and that clinicians may be faced with reconciling how a normatively intact cognitive performance on the Recognition subtest could simultaneously reflect invalid performance validity.

Discriminative ability of commonly used indices to predict adverse outcomes after poster lumbar fusion: a comparison of demographics, ASA, the modified Charlson Comorbidity Index, and the modified Frailty Index.

PubMed

Ondeck, Nathaniel T; Bohl, Daniel D; Bovonratwet, Patawut; McLynn, Ryan P; Cui, Jonathan J; Shultz, Blake N; Lukasiewicz, Adam M; Grauer, Jonathan N

2018-01-01

As research tools, the American Society of Anesthesiologists (ASA) physical status classification system, the modified Charlson Comorbidity Index (mCCI), and the modified Frailty Index (mFI) have been associated with complications following spine procedures. However, with respect to clinical use for various adverse outcomes, no known study has compared the predictive performance of these indices specifically following posterior lumbar fusion (PLF). This study aimed to compare the discriminative ability of ASA, mCCI, and mFI, as well as demographic factors including age, body mass index, and gender for perioperative adverse outcomes following PLF. A retrospective review of prospectively collected data was performed. Patients undergoing elective PLF with or without interbody fusion were extracted from the 2011-2014 American College of Surgeons National Surgical Quality Improvement Program (NSQIP). Perioperative adverse outcome variables assessed included the occurrence of minor adverse events, severe adverse events, infectious adverse events, any adverse event, extended length of hospital stay, and discharge to higher-level care. Patient comorbidity indices and characteristics were delineated and assessed for discriminative ability in predicting perioperative adverse outcomes using an area under the curve analysis from the receiver operating characteristics curves. In total, 16,495 patients were identified who met the inclusion criteria. The most predictive comorbidity index was ASA and demographic factor was age. Of these two factors, age had the larger discriminative ability for three out of the six adverse outcomes and ASA was the most predictive for one out of six adverse outcomes. A combination of the most predictive demographic factor and comorbidity index resulted in improvements in discriminative ability over the individual components for five of the six outcome variables. For PLF, easily obtained patient ASA and age have overall similar or better discriminative abilities for perioperative adverse outcomes than numerically tabulated indices that have multiple inputs and are harder to implement in clinical practice. Copyright © 2017 Elsevier Inc. All rights reserved.

Digital radiography: are the manufacturers' settings too high? Optimisation of the Kodak digital radiography system with aid of the computed radiography dose index.

PubMed

Peters, Sinead E; Brennan, Patrick C

2002-09-01

Manufacturers offer exposure indices as a safeguard against overexposure in computed radiography, but the basis for recommended values is unclear. This study establishes an optimum exposure index to be used as a guideline for a specific CR system to minimise radiation exposures for computed mobile chest radiography, and compares this with manufacturer guidelines and current practice. An anthropomorphic phantom was employed to establish the minimum milliamperes consistent with acceptable image quality for mobile chest radiography images. This was found to be 2 mAs. Consecutively, 10 patients were exposed with this optimised milliampere value and 10 patients were exposed with the 3.2 mAs routinely used in the department of the study. Image quality was objectively assessed using anatomical criteria. Retrospective analyses of 717 exposure indices recorded over 2 months from mobile chest examinations were performed. The optimised milliampere value provided a significant reduction of the average exposure index from 1840 to 1570 ( p<0.0001). This new "optimum" exposure index is substantially lower than manufacturer guidelines of 2000 and significantly lower than exposure indices from the retrospective study (1890). Retrospective data showed a significant increase in exposure indices if the examination was performed out of hours. The data provided by this study emphasise the need for clinicians and personnel to consider establishing their own optimum exposure indices for digital investigations rather than simply accepting manufacturers' guidelines. Such an approach, along with regular monitoring of indices, may result in a substantial reduction in patient exposure.

SU-E-I-32: Benchmarking Head CT Doses: A Pooled Vs. Protocol Specific Analysis of Radiation Doses in Adult Head CT Examinations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujii, K; UCLA School of Medicine, Los Angeles, CA; Bostani, M

Purpose: The aim of this study was to collect CT dose index data from adult head exams to establish benchmarks based on either: (a) values pooled from all head exams or (b) values for specific protocols. One part of this was to investigate differences in scan frequency and CT dose index data for inpatients versus outpatients. Methods: We collected CT dose index data (CTDIvol) from adult head CT examinations performed at our medical facilities from Jan 1st to Dec 31th, 2014. Four of these scanners were used for inpatients, the other five were used for outpatients. All scanners used Tubemore » Current Modulation. We used X-ray dose management software to mine dose index data and evaluate CTDIvol for 15807 inpatients and 4263 outpatients undergoing Routine Brain, Sinus, Facial/Mandible, Temporal Bone, CTA Brain and CTA Brain-Neck protocols, and combined across all protocols. Results: For inpatients, Routine Brain series represented 84% of total scans performed. For outpatients, Sinus scans represented the largest fraction (36%). The CTDIvol (mean ± SD) across all head protocols was 39 ± 30 mGy (min-max: 3.3–540 mGy). The CTDIvol for Routine Brain was 51 ± 6.2 mGy (min-max: 36–84 mGy). The values for Sinus were 24 ± 3.2 mGy (min-max: 13–44 mGy) and for Facial/Mandible were 22 ± 4.3 mGy (min-max: 14–46 mGy). The mean CTDIvol for inpatients and outpatients was similar across protocols with one exception (CTA Brain-Neck). Conclusion: There is substantial dose variation when results from all protocols are pooled together; this is primarily a function of the differences in technical factors of the protocols themselves. When protocols are analyzed separately, there is much less variability. While analyzing pooled data affords some utility, reviewing protocols segregated by clinical indication provides greater opportunity for optimization and establishing useful benchmarks.« less

Better state-of-good-repair indicators for the transportation performance index.

DOT National Transportation Integrated Search

2014-07-01

The Transportation Performance Index was developed for the US Chamber of Commerce to track the : performance of transportation infrastructure over time and explore the connection between economic : health and infrastructure performance. This project ...

The Femoro-Epiphyseal Acetabular Roof (FEAR) Index: A New Measurement Associated With Instability in Borderline Hip Dysplasia?

PubMed

Wyatt, Michael; Weidner, Jan; Pfluger, Dominik; Beck, Martin

2017-03-01

The definition of osseous instability in radiographic borderline dysplastic hips is difficult. A reliable radiographic tool that aids decision-making-specifically, a tool that might be associated with instability-therefore would be very helpful for this group of patients. (1) To compare a new radiographic measurement, which we call the Femoro-Epiphyseal Acetabular Roof (FEAR) index, with the lateral center-edge angle (LCEA) and acetabular index (AI), with respect to intra- and interobserver reliability; (2) to correlate AI, neck-shaft angle, LCEA, iliocapsularis volume, femoral antetorsion, and FEAR index with the surgical treatment received in stable and unstable borderline dysplastic hips; and (3) to assess whether the FEAR index is associated clinical instability in borderline dysplastic hips. We defined and validated the FEAR index in 10 standardized radiographs of asymptomatic controls using two blinded independent observers. Interrater and intrarater coefficients were calculated, supplemented by Bland-Altman plots. We compared its reliability with LCEA and AI. We performed a case-control study using standardized radiographs of 39 surgically treated symptomatic borderline radiographically dysplastic hips and 20 age-matched controls with asymptomatic hips (a 2:1 ratio), the latter were patients attending our institution for trauma unrelated to their hips but who had standardized pelvic radiographs between January 1, 2016 and March 1, 2016. Patient demographics were assessed using univariate Wilcoxon two-sample tests. There was no difference in mean age (overall: 31.5 ± 11.8 years [95% CI, 27.7-35.4 years]; stable borderline group: mean, 32.1± 13.3 years [95% CI, 25.5-38.7 years]; unstable borderline group: mean, 31.1 ± 10.7 years [95% CI, 26.2-35.9 years]; p = 0.96) among study groups. Treatment received was either a periacetabular osteotomy (if the hip was unstable) or, for patients with femoroacetabular impingement, either an open or arthroscopic femoroacetabular impingement procedure. The association of received treatment categories with the variables AI, neck-shaft angle, LCEA, iliocapsularis volume, femoral antetorsion, and FEAR index were evaluated first using Wilcoxon two-sample tests (two-sided) followed by stepwise multiple logistic regression analysis to identify the potential associated variables in a combined setting. Sensitivity, specificity, and receiver operator curves were calculated. The primary endpoint was the association between the FEAR index and instability, which we defined as migration of the femoral head either already visible on conventional radiographs or recentering of the head on AP abduction views, a break of Shenton's line, or the appearance of a crescent-shaped accumulation of gadolinium in the posteroinferior joint space at MR arthrography. The FEAR index showed excellent intra- and interobserver reliability, superior to the AI and LCEA. The FEAR index was lower in the stable borderline group (mean, -2.1 ± 8.4; 95% CI, -6.3 to 2.0) compared with the unstable borderline group (mean, 13.3 ± 15.2; 95% CI, 6.2-20.4) (p < 0.001) and had the highest association with treatment received. A FEAR index less than 5° had a 79% probability of correctly assigning hips as stable and unstable, respectively (sensitivity 78%; specificity 80%). A painful hip with a LCEA of 25° or less and FEAR index less than 5° is likely to be stable, and in such a situation, the diagnostic focus might more productively be directed toward femoroacetabular impingement as a potential cause of a patient's pain, rather than instability. Level III, diagnostic study.

Airway physical examination tests for detection of difficult airway management in apparently normal adult patients.

PubMed

Roth, Dominik; Pace, Nathan L; Lee, Anna; Hovhannisyan, Karen; Warenits, Alexandra-Maria; Arrich, Jasmin; Herkner, Harald

2018-05-15

The unanticipated difficult airway is a potentially life-threatening event during anaesthesia or acute conditions. An unsuccessfully managed upper airway is associated with serious morbidity and mortality. Several bedside screening tests are used in clinical practice to identify those at high risk of difficult airway. Their accuracy and benefit however, remains unclear. The objective of this review was to characterize and compare the diagnostic accuracy of the Mallampati classification and other commonly used airway examination tests for assessing the physical status of the airway in adult patients with no apparent anatomical airway abnormalities. We performed this individually for each of the four descriptors of the difficult airway: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation. We searched major electronic databases including CENTRAL, MEDLINE, Embase, ISI Web of Science, CINAHL, as well as regional, subject specific, and dissertation and theses databases from inception to 16 December 2016, without language restrictions. In addition, we searched the Science Citation Index and checked the references of all the relevant studies. We also handsearched selected journals, conference proceedings, and relevant guidelines. We updated this search in March 2018, but we have not yet incorporated these results. We considered full-text diagnostic test accuracy studies of any individual index test, or a combination of tests, against a reference standard. Participants were adults without obvious airway abnormalities, who were having laryngoscopy performed with a standard laryngoscope and the trachea intubated with a standard tracheal tube. Index tests included the Mallampati test, modified Mallampati test, Wilson risk score, thyromental distance, sternomental distance, mouth opening test, upper lip bite test, or any combination of these. The target condition was difficult airway, with one of the following reference standards: difficult face mask ventilation, difficult laryngoscopy, difficult tracheal intubation, and failed intubation. We performed screening and selection of the studies, data extraction and assessment of methodological quality (using QUADAS-2) independently and in duplicate. We designed a Microsoft Access database for data collection and used Review Manager 5 and R for data analysis. For each index test and each reference standard, we assessed sensitivity and specificity. We produced forest plots and summary receiver operating characteristic (ROC) plots to summarize the data. Where possible, we performed meta-analyses to calculate pooled estimates and compare test accuracy indirectly using bivariate models. We investigated heterogeneity and performed sensitivity analyses. We included 133 (127 cohort type and 6 case-control) studies involving 844,206 participants. We evaluated a total of seven different prespecified index tests in the 133 studies, as well as 69 non-prespecified, and 32 combinations. For the prespecified index tests, we found six studies for the Mallampati test, 105 for the modified Mallampati test, six for the Wilson risk score, 52 for thyromental distance, 18 for sternomental distance, 34 for the mouth opening test, and 30 for the upper lip bite test. Difficult face mask ventilation was the reference standard in seven studies, difficult laryngoscopy in 92 studies, difficult tracheal intubation in 50 studies, and failed intubation in two studies. Across all studies, we judged the risk of bias to be variable for the different domains; we mostly observed low risk of bias for patient selection, flow and timing, and unclear risk of bias for reference standard and index test. Applicability concerns were generally low for all domains. For difficult laryngoscopy, the summary sensitivity ranged from 0.22 (95% confidence interval (CI) 0.13 to 0.33; mouth opening test) to 0.67 (95% CI 0.45 to 0.83; upper lip bite test) and the summary specificity ranged from 0.80 (95% CI 0.74 to 0.85; modified Mallampati test) to 0.95 (95% CI 0.88 to 0.98; Wilson risk score). The upper lip bite test for diagnosing difficult laryngoscopy provided the highest sensitivity compared to the other tests (P < 0.001). For difficult tracheal intubation, summary sensitivity ranged from 0.24 (95% CI 0.12 to 0.43; thyromental distance) to 0.51 (95% CI 0.40 to 0.61; modified Mallampati test) and the summary specificity ranged from 0.87 (95% CI 0.82 to 0.91; modified Mallampati test) to 0.93 (0.87 to 0.96; mouth opening test). The modified Mallampati test had the highest sensitivity for diagnosing difficult tracheal intubation compared to the other tests (P < 0.001). For difficult face mask ventilation, we could only estimate summary sensitivity (0.17, 95% CI 0.06 to 0.39) and specificity (0.90, 95% CI 0.81 to 0.95) for the modified Mallampati test. Bedside airway examination tests, for assessing the physical status of the airway in adults with no apparent anatomical airway abnormalities, are designed as screening tests. Screening tests are expected to have high sensitivities. We found that all investigated index tests had relatively low sensitivities with high variability. In contrast, specificities were consistently and markedly higher than sensitivities across all tests. The standard bedside airway examination tests should be interpreted with caution, as they do not appear to be good screening tests. Among the tests we examined, the upper lip bite test showed the most favourable diagnostic test accuracy properties. Given the paucity of available data, future research is needed to develop tests with high sensitivities to make them useful, and to consider their use for screening difficult face mask ventilation and failed intubation. The 27 studies in 'Studies awaiting classification' may alter the conclusions of the review, once we have assessed them.

Sex and age differences in physical performance: A comparison of Army basic training and operational populations.

PubMed

Dada, Esther O; Anderson, Morgan K; Grier, Tyson; Alemany, Joseph A; Jones, Bruce H

2017-11-01

To determine the age- and sex-specific differences of physical fitness performances and Body Mass Index (BMI) in basic training and the operational Army. Cross-sectional Study. This secondary analysis utilizes retrospective surveys of U.S. Army Soldiers in Basic Combat Training (BCT) and operational units to compare physical performances between men and women as measured by the Army Physical Readiness Test (APFT). An ANOVA was used to compare mean differences in APFT results and BMI within sex-specific populations. A post hoc Tukey test identified specific mean differences. Adjusting for age, an ANCOVA was used to compare sex and occupation (infantry and non-infantry) differences in APFT results. Surveyed populations consisted of 2216 BCT Soldiers (1573 men and 643 women) and 5515 Operational Soldiers (4987 men and 528 women). Male and female operational Soldiers had greater muscular performance (79%-125% higher APFT push-ups, 66%-85% higher APFT sit-ups) and cardiorespiratory performance (22%-24% faster APFT 2-mile run times) than BCT Soldiers. Male BCT and operational Soldiers outperform their female counterparts on tests of muscular and cardiorespiratory endurance. Sex differences in physical performances attenuated among female Soldiers in operational units compared to BCT. Among male operational Soldiers, infantry Soldiers exhibited greater cardiorespiratory and muscular performance than non-infantry Soldiers. Higher BMI was associated with higher age groups, except for female BCT Soldiers. Gaps in cardiorespiratory and muscular performances between men and women should be addressed through targeted physical training programs that aim to minimize physiological differences. Published by Elsevier Ltd.

Renal perfusion index reflects cardiac systolic function in chronic cardio-renal syndrome.

PubMed

Lubas, Arkadiusz; Ryczek, Robert; Kade, Grzegorz; Niemczyk, Stanisław

2015-04-17

Cardiac dysfunction can modify renal perfusion, which is crucial to maintain sufficient kidney tissue oxygenation. Renal cortex perfusion assessed by dynamic ultrasound method is related both to renal function and cardiac hemodynamics. The aim of the study was to test the hypothesis that Renal Perfusion Index (RPI) can more closely reflect cardiac hemodynamics and differentiate etiology of chronic cardio-renal syndrome. Twenty-four patients with hypertension and chronic kidney disease (CKD) at 2-4 stage (12 with hypertensive nephropathy and 12 with CKD prior to hypertension) were enrolled in the study. Blood tests, 24-h ABPM, echocardiography, and ultrasonography with estimation of Total renal Cortical Perfusion intensity and Renal Perfusion Index (RPI) were performed. In the group of all patients, RPI correlated with left ventricular stoke volume (LVSV), and cardiac index, but not with markers of renal function. In multiple stepwise regression analysis CKD-EPI(Cys-Cr) (b=-0.360), LVSV (b=0.924) and MAP (b=0.376) together independently influenced RPI (R2=0.74; p<0.0001). RPI<0.567 allowed for the identification of patients with chronic cardio-renal syndrome with sensitivity of 41.7% and specificity of 83.3%. Renal perfusion index relates more strongly to cardiac output than to renal function, and could be helpful in recognizing chronic cardio-renal syndrome. Applicability of RPI in diagnosing early abnormalities in the cardio-renal axis requires further investigation.

Extraordinary-mode refractive-index change produced by the linear electro-optic effect in LiNbO3 and reverse-poled LiNbO3

NASA Astrophysics Data System (ADS)

Boyd, Joseph T.; Servizzi, Anthony J.; Sriram, S.; Kingsley, Stuart A.

1995-07-01

To examine aspects of an integrated photonic electric-field sensor, we calculate electro-optically induced refractive-index change in regular and reverse-poled LiNbO3. Specifically, for y-propagating extraordinary modes, we determine how index change depends on electric-field magnitude and direction. To accomplish this, changes in index-ellipsoid shape and orientation are found by the use of a numerical eigenvalue procedure to diagonalize the impermeability tensor; then, refractive index is calculated by the use of a vector reference-frame transformation and a small perturbation approximation. A general formula is inferred from calculations for specific field directions. Electro-optic coefficients for reverse-poled LiNbO3 are obtained by application of a tensor reference-frame transformation to those of LiNbO3. The index-calculation procedure has utility beyond the problem that is considered.

Publications of the Jet Propulsion Laboratory, 1984

NASA Technical Reports Server (NTRS)

1985-01-01

The Jet Propulsion Laboratory (JPL) bibliography 39-26 describes and indexes by primary author the externally distributed technical reporting, released during calendar year 1984, that resulted from scientific and engineering work performed, or managed, by the Jet Propulsion Laboratory. Three classes of publications are included: (1) JPL Publications (82-, 83-, 84-series, etc.), in which the information is complete for a specific accomplishment; (2) articles from the quarterly Telecommunications and Data Acquisition (TDA) Program Report (42-series); and (3) articles published in the open literature.

Publications of the Jet Propulsion Laboratory: 1990 and 1991

NASA Technical Reports Server (NTRS)

1993-01-01

JPL Bibliography 39-32 describes and indexes by primary author the externally distributed technical reporting, released during calendar years 1990 and 1991, that resulted from scientific and engineering work performed or managed by the Jet Propulsion Laboratory (JPL). Three classes of publications are included: (1) JPL publications (90- and 91-series) in which the information is complete for a specific accomplishment; (2) articles from the quarterly Telecommunications and Data Acquisition (TDA) Progress Report (42-series); and (3) articles published in the open literature.

Functional design specification: NASA form 1510

NASA Technical Reports Server (NTRS)

1979-01-01

The 1510 worksheet used to calculate approved facility project cost estimates is explained. Topics covered include data base considerations, program structure, relationship of the 1510 form to the 1509 form, and functions which the application must perform: WHATIF, TENENTER, TENTYPE, and data base utilities. A sample NASA form 1510 printout and a 1510 data dictionary are presented in the appendices along with the cost adjustment table, the floppy disk index, and methods for generating the calculated values (TENCALC) and for calculating cost adjustment (CONSTADJ). Storage requirements are given.

Improving activities of daily living for nursing home elder persons in Taiwan.

PubMed

Chang, Su-Hsien; Wung, Shu-Fen; Crogan, Neva L

2008-01-01

Excess disability among nursing home elder persons can be prevented or remediated. Because of self-selected disuse and caregiver support of dependency, nursing home residents are likely to develop excess disability. No study was found to test a theory-based program aimed at improving elder persons' self-care abilities for Taiwanese nursing home elder persons who are at risk for developing excess disability. The purpose of this study was to test the effectiveness of a theory-based intervention program on self-care, specifically on activities of daily living (ADLs) performance among nursing home elder persons in Taiwan. A secondary aim was to determine the correlation between ADLs performance and three bliss concepts: life satisfaction, self-esteem, and motivation in health behavior. This study used a quasi-experimental, two-group, pretest-posttest design. Forty-two qualified participants were recruited from two nursing homes located in southern Taiwan and assigned to either the experimental group (n = 21) or the comparison group (n = 21). Participants in the experimental group received the Self-Care Self-Efficacy Enhancement Program (SCSEEP), and those in the comparison group received biweekly social visits for 6 weeks. Levels of ADLs performance were measured by Tappen's Refined ADL Assessment Scale. Life satisfaction was measured by Adams' Life Satisfaction Index A. Self-esteem was measured by Rosenberg's Self-Esteem Scale. Motivation in health behavior was measured by Cox's Health Self-Determinism Index. Elder persons receiving the SCSEEP had significant improvement in feeding, dressing, grooming, and washing activities. Self-esteem (p = .011) and life satisfaction (p = .033) but not motivation in health behavior (p = .282) were positively correlated with levels of ADLs performance. The SCSEEP provides a theory-based intervention model for Taiwanese nursing home elder persons aimed at improving ADLs performance. Further research with a larger sample size is needed to determine the long-term maintenance and effectiveness of this theory-driven SCSEEP in specific culture groups.

Adjusting Health Expenditures for Inflation: A Review of Measures for Health Services Research in the United States.

PubMed

Dunn, Abe; Grosse, Scott D; Zuvekas, Samuel H

2018-02-01

To provide guidance on selecting the most appropriate price index for adjusting health expenditures or costs for inflation. Major price index series produced by federal statistical agencies. We compare the key characteristics of each index and develop suggestions on specific indexes to use in many common situations and general guidance in others. Price series and methodological documentation were downloaded from federal websites and supplemented with literature scans. The gross domestic product implicit price deflator or the overall Personal Consumption Expenditures (PCE) index is preferable to the Consumer Price Index (CPI-U) to adjust for general inflation, in most cases. The Personal Health Care (PHC) index or the PCE health-by-function index is generally preferred to adjust total medical expenditures for inflation. The CPI medical care index is preferred for the adjustment of consumer out-of-pocket expenditures for inflation. A new, experimental disease-specific Medical Care Expenditure Index is now available to adjust payments for disease treatment episodes. There is no single gold standard for adjusting health expenditures for inflation. Our discussion of best practices can help researchers select the index best suited to their study. © Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Basophil responsiveness and clinical picture of acetylsalicylic acid intolerance.

PubMed

Korosec, Peter; Mavsar, Nusa; Bajrovic, Nissera; Silar, Mira; Mrhar, Ales; Kosnik, Mitja

2011-01-01

Exposure to acetylsalicylic acid (ASA) may exacerbate respiratory or skin diseases or induce anaphylactoid reactions in apparently healthy individuals. We wanted to evaluate specific responsiveness of basophils to ASA in correlation with the clinical picture. We performed a prospective single-blind study of 59 subjects involved in clinical evaluation and/or ASA provocation testing. Whole blood basophils were stained with anti-CD63/CD123/HLA-DR mAbs after stimulation with 0.25 or 1 mg/ml ASA. We found that 40 subjects were ASA tolerant and 19 were ASA intolerant. Both groups had comparable manifestations of asthma and/or rhinitis (13 in the tolerant and 9 in the intolerant group). Intolerant subjects showed significantly higher basophil responsiveness to ASA in comparison to tolerant subjects, which was concentration-dependent in both groups. The ratio between responses at 1 mg/ml of ASA and at baseline (activation index) was analyzed according to the clinical picture. We demonstrate that the activation index was higher only in the intolerant subjects with anaphylactoid reactions, but not in a subgroup of subjects with asthma/rhinitis. The ROC calculations show that the optimal threshold activation index was more than 2.18. The sensitivity was 80% and the specificity was 83% in the subgroup with anaphylactoid reactions. In the asthma/rhinitis subgroup, the sensitivity was 78% and the specificity was 50%. Our study demonstrates that there is a significantly higher in vitro basophil response to ASA in intolerant as compared to tolerant subjects. ROC analyses suggest that this measurement might only have a diagnostic value in subjects without asthma and/or rhinitis. Copyright © 2011 S. Karger AG, Basel.

Using the Karolinska Sleep Questionnaire to identify obstructive sleep apnea syndrome in a sleep clinic population.

PubMed

Westerlund, Anna; Brandt, Lena; Harlid, Richard; Åkerstedt, Torbjörn; Lagerros, Ylva Trolle

2014-10-01

In Scandinavia, portable monitoring has virtually replaced standard polysomnography for diagnosis of obstructive sleep apnea syndrome (OSAS). Because waiting times for specialized OSAS care remain long, an accurate screening tool to exclude low-risk patients from diagnostic testing would be valuable. To examine the diagnostic accuracy of the Karolinska Sleep Questionnaire (KSQ) for OSAS. Consecutive patients, 30–66 years old, attending a large sleep clinic in Sweden for OSAS evaluation completed the KSQ and underwent in-home portable monitoring and medical history evaluation. OSAS was defined as apnea-hypopnea index ≥5 with symptoms of disease. We calculated sensitivity and specificity of apnea/snoring and sleepiness indices of the KSQ. Retrospectively, we combined six KSQ items (snoring, breathing cessations, disturbed sleep, etc.) and four clinical variables (age, sex, body mass index, smoking status) predictive of OSAS into a new instrument, which we also evaluated. Instrument score ranged between 0 and 21; a higher score indicated more severe symptoms. Of 103 patients, 62 were diagnosed with OSAS. Sensitivity and specificity of the indices were 0.56 and 0.68 (apnea/snoring), and 0.37 and 0.71 (sleepiness). The new instrument performed optimally at a score of 9. Sensitivity was 0.76 (95% confidence interval 0.63–0.86) and specificity 0.88 (0.74–0.96). Between 19.4% and 50.5% of patients were unaware of having apnea/snoring symptoms. Diagnostic accuracy of the apnea/snoring and sleepiness indices for OSAS was poor but could be improved by combining clinical and KSQ items. The usefulness of the apnea/snoring index and the combined instrument was questionable because of extensive symptom unawareness.

Diagnostic test accuracy study of 18F-sodium fluoride PET/CT, 99mTc-labelled diphosphonate SPECT/CT, and planar bone scintigraphy for diagnosis of bone metastases in newly diagnosed, high-risk prostate cancer

PubMed Central

Fonager, Randi F; Zacho, Helle D; Langkilde, Niels C; Fledelius, Joan; Ejlersen, June A; Haarmark, Christian; Hendel, Helle W; Lange, Mine Benedicte; Jochumsen, Mads R; Mortensen, Jesper C; Petersen, Lars J

2017-01-01

The aim of this study was to prospectively compare planar, bone scan (BS) versus SPECT/CT and NaF PET/CT in detecting bone metastases in prostate cancer. Thirty-seven consecutive, newly diagnosed, prostate cancer patients with prostate specific antigen (PSA) levels ≥ 50 ng/mL and who were considered eligible for androgen-deprivation therapy (ADT) were included in this study. BS, SPECT/CT, and NaF PET/CT, were performed prior to treatment and were repeated after six months of ADT. Baseline images from each index test were independently read by two experienced readers. The reference standard was based on a consensus decision made by a multidisciplinary team on the basis of baseline and follow-up images of the index tests, the findings of the baseline index tests by the experienced readers, and any available imaging, biochemical, and clinical data, including the response to ADT. Twenty-seven (73%) of the 37 patients had bone metastases according to the reference standard. The sensitivities for BS, SPECT/CT and NaF PET/CT were 78%, 89%, and 89%, respectively, and the specificities were 90%, 100%, and 90%, respectively. The positive predictive values of BS, SPECT/CT and NaF PET/CT were 96%, 100%, and 96%, respectively, and the negative predictive values were 60%, 77% and 75%, respectively. No statistically significant difference among the three imaging modalities was observed. All three imaging modalities showed high sensitivity and specificity. NaF PET/CT and SPECT/CT showed numerically improved, but not statistically superior, sensitivity compared with BS in this limited and selected patient cohort. PMID:29181269

Rural-Urban Differences in Trends in the Wealth Index in Kenya: 1993-2009.

PubMed

Egede, Leonard E; Voronca, Delia; Walker, Rebekah J; Thomas, Craig

The aim of this study was to construct a wealth index that could be compared over time in order to understand the trends in wealth in Kenya and determine predictors of change in wealth index. Data were from the Demographic and Health Survey program collected in Kenya between 1993 and 2009. Variable categories were collapsed to match and factor analysis was performed on the 4-year pooled data to generate a harmonized wealth index. Possible predictors of wealth were selected from household variables available for all 4 years. Household sampling weights and stratification by rural/urban was used. Overall, wealth increased in Kenya between 1993 and 2008; however, when stratified, no significant increase existed in urban areas and a significant increase was identified in rural areas specifically between 2003 and 2008. The strongest predictor was education, with more than a standard deviation difference for secondary or higher levels of education over those with no education. The association of gender of the head of household and whether the head of household had a partner differed between rural and urban areas, with household heads who were women and those who had a partner having more wealth in urban areas but less wealth in rural areas. Wealth in Kenya increased over time, specifically in rural regions. Differences were identified in predictors of wealth by urban/rural residence, educational level, and gender of the head of household and should be taken into account when planning interventions to target those in disproportionately low wealth brackets. Copyright © 2017 Icahn School of Medicine at Mount Sinai. Published by Elsevier Inc. All rights reserved.

Adaptive semi-supervised recursive tree partitioning: The ART towards large scale patient indexing in personalized healthcare.

PubMed

Wang, Fei

2015-06-01

With the rapid development of information technologies, tremendous amount of data became readily available in various application domains. This big data era presents challenges to many conventional data analytics research directions including data capture, storage, search, sharing, analysis, and visualization. It is no surprise to see that the success of next-generation healthcare systems heavily relies on the effective utilization of gigantic amounts of medical data. The ability of analyzing big data in modern healthcare systems plays a vital role in the improvement of the quality of care delivery. Specifically, patient similarity evaluation aims at estimating the clinical affinity and diagnostic proximity of patients. As one of the successful data driven techniques adopted in healthcare systems, patient similarity evaluation plays a fundamental role in many healthcare research areas such as prognosis, risk assessment, and comparative effectiveness analysis. However, existing algorithms for patient similarity evaluation are inefficient in handling massive patient data. In this paper, we propose an Adaptive Semi-Supervised Recursive Tree Partitioning (ART) framework for large scale patient indexing such that the patients with similar clinical or diagnostic patterns can be correctly and efficiently retrieved. The framework is designed for semi-supervised settings since it is crucial to leverage experts' supervision knowledge in medical scenario, which are fairly limited compared to the available data. Starting from the proposed ART framework, we will discuss several specific instantiations and validate them on both benchmark and real world healthcare data. Our results show that with the ART framework, the patients can be efficiently and effectively indexed in the sense that (1) similarity patients can be retrieved in a very short time; (2) the retrieval performance can beat the state-of-the art indexing methods. Copyright © 2015. Published by Elsevier Inc.

[Non-invasive fibrosis indexes in predicting acute liver function deterioration after transcatheter arterial chemoembolization].

PubMed

Song, Y P; Zhao, Q Y; Li, S; Wang, H; Wu, P H

2016-03-08

To investigate the ability of two non-invasive fibrosis indexes-APRI, i. e. aspartate transaminase (AST) to platelet (PLT) ratio index, and fibrosis index based on the 4 factors (FIB-4)score in predicting ALFD in patients with unresectable primary HCC and underwent TACE. Clinical data of those patients treated with TACE in Department of Interventional Radiology of the Center from Jan 2010 to Aug 2014 were investigated retrospectively. A total of 366 cases were enrolled after randomized selection, 62 (18.5%) of which developed ALFD after TACE. Child-Pugh score, APRI and FIB-4 score in every case were calculated, receiver operating characteristic (ROC) curve of each model were performed and the predictive abilities of them were assessed by area under the curve (AUC), positive predictive value (PPV), negative predictive value (NPV), sensitivity and specificity. The AUC of Child-Pugh score, APRI and FIB-4 score were 0.783, 0.752 and 0.758 respectively, while the difference had no significance in statistics, indicating that predictive accuracies of them were similar. APRI≤1.15 and FIB-4≤3.08 had better NPV (90.6% and 93.6%) and sensitivity (65.6% and 80.0%) than Child-Pugh score>6 (NPV=85.8%, sensitivity=27.4%), PPV and specificity of them are 35.7%, 32.9%, 89.5% and 73.7%, 64.2%, 99.3% respectively. Comparing to Child-Pugh score, APRI and FIB-4 score have similar accuracy but better NPV and sensitivity in predicting post-TACE ALFD. Thereafter they are good for selection of low-risk patients for TACE treatment. Candidates with an APRI≤1.15 or a FIB-4≤3.08 or in Child-Pugh a stage are unlikely to develop ALFD thus could receive TACE safely.

Scientometrics of anesthetic drugs and their techniques of administration, 1984-2013.

PubMed

Vlassakov, Kamen V; Kissin, Igor

2014-01-01

The aim of this study was to assess progress in the field of anesthetic drugs over the past 30 years using scientometric indices: popularity indices (general and specific), representing the proportion of articles on a drug relative to all articles in the field of anesthetics (general index) or the subfield of a specific class of anesthetics (specific index); index of change, representing the degree of growth in publications on a topic from one period to the next; index of expectations, representing the ratio of the number of articles on a topic in the top 20 journals relative to the number of articles in all (>5,000) biomedical journals covered by PubMed; and index of ultimate success, representing a publication outcome when a new drug takes the place of a common drug previously used for the same purpose. Publications on 58 topics were assessed during six 5-year periods from 1984 to 2013. Our analysis showed that during 2009-2013, out of seven anesthetics with a high general popularity index (≥2.0), only two were introduced after 1980, ie, the inhaled anesthetic sevoflurane and the local anesthetic ropivacaine; however, only sevoflurane had a high index of expectations (12.1). Among anesthetic adjuncts, in 2009-2013, only one agent, sugammadex, had both an extremely high index of change (>100) and a high index of expectations (25.0), reflecting the novelty of its mechanism of action. The index of ultimate success was positive with three anesthetics, ie, lidocaine, isoflurane, and propofol, all of which were introduced much longer than 30 years ago. For the past 30 years, there were no new anesthetics that have produced changes in scientometric indices indicating real progress.

Scientometrics of anesthetic drugs and their techniques of administration, 1984–2013

PubMed Central

Vlassakov, Kamen V; Kissin, Igor

2014-01-01

The aim of this study was to assess progress in the field of anesthetic drugs over the past 30 years using scientometric indices: popularity indices (general and specific), representing the proportion of articles on a drug relative to all articles in the field of anesthetics (general index) or the subfield of a specific class of anesthetics (specific index); index of change, representing the degree of growth in publications on a topic from one period to the next; index of expectations, representing the ratio of the number of articles on a topic in the top 20 journals relative to the number of articles in all (>5,000) biomedical journals covered by PubMed; and index of ultimate success, representing a publication outcome when a new drug takes the place of a common drug previously used for the same purpose. Publications on 58 topics were assessed during six 5-year periods from 1984 to 2013. Our analysis showed that during 2009–2013, out of seven anesthetics with a high general popularity index (≥2.0), only two were introduced after 1980, ie, the inhaled anesthetic sevoflurane and the local anesthetic ropivacaine; however, only sevoflurane had a high index of expectations (12.1). Among anesthetic adjuncts, in 2009–2013, only one agent, sugammadex, had both an extremely high index of change (>100) and a high index of expectations (25.0), reflecting the novelty of its mechanism of action. The index of ultimate success was positive with three anesthetics, ie, lidocaine, isoflurane, and propofol, all of which were introduced much longer than 30 years ago. For the past 30 years, there were no new anesthetics that have produced changes in scientometric indices indicating real progress. PMID:25525336

Sensitivity of the Halstead and Wechsler Test Batteries to brain damage: Evidence from Reitan's original validation sample.

PubMed

Loring, David W; Larrabee, Glenn J

2006-06-01

The Halstead-Reitan Battery has been instrumental in the development of neuropsychological practice in the United States. Although Reitan administered both the Wechsler-Bellevue Intelligence Scale and Halstead's test battery when evaluating Halstead's theory of biologic intelligence, the relative sensitivity of each test battery to brain damage continues to be an area of controversy. Because Reitan did not perform direct parametric analysis to contrast group performances, we reanalyze Reitan's original validation data from both Halstead (Reitan, 1955) and Wechsler batteries (Reitan, 1959a) and calculate effect sizes and probability levels using traditional parametric approaches. Eight of the 10 tests comprising Halstead's original Impairment Index, as well as the Impairment Index itself, statistically differentiated patients with unequivocal brain damage from controls. In addition, 13 of 14 Wechsler measures including Full-Scale IQ also differed statistically between groups (Brain Damage Full-Scale IQ = 96.2; Control Group Full Scale IQ = 112.6). We suggest that differences in the statistical properties of each battery (e.g., raw scores vs. standardized scores) likely contribute to classification characteristics including test sensitivity and specificity.

Combined use of Kappa Free Light Chain Index and Isoelectrofocusing of Cerebro-Spinal Fluid in Diagnosing Multiple Sclerosis: Performances and Costs.

PubMed

Crespi, Ilaria; Sulas, Maria Giovanna; Mora, Riccardo; Naldi, Paola; Vecchio, Domizia; Comi, Cristoforo; Cantello, Roberto; Bellomo, Giorgio

2017-03-01

Isoelectrofocusing (IEF) to detect oligoclonal bands (OBCs) in cerebrospinal fluid (CSF) is the gold standard approach for evaluating intrathecal immunoglobulin synthesis in multiple sclerosis (MS) but the kappa free light chain index (KFLCi) is emerging as an alternative marker, and the combined/sequential uses of IEF and KFLCi have never been challenged. CSF and serum albumin, IgG, kFLC and lFLC were measured by nephelometry; albumin, IgG and kFLC quotients as well as Link and kFLC indexes were calculated; OCBs were evaluated by immunofixation. A total of 150 consecutive patients: 48 with MS, 32 with other neurological inflammatory diseases (NID), 62 with neurological non-inflammatory diseases (NNID), and 8 without any detectable neurological disease (NND) were investigated. Both IEF and KFLCi showed a similar accuracy as diagnostic tests for multiple sclerosis. The high sensitivity and specificity associated with the lower cost of KFLCi suggested to use this test first, followed by IEF as a confirmative procedure. The sequential use of IEF and KFLCi showed high diagnostic efficiency with cost reduction of 43 and 21%, if compared to the contemporary use of both tests, or the unique use of IEF in all patients. The "sequential testing" using KFLCi followed by IEF in MS represents an optimal procedure with accurate performance and lower costs.

[Clinical auxiliary diagnosis value of high frequency ultrasonographic measurements of the thickness of transverse carpal ligaments in carpal tunnel syndrome patients].

PubMed

Xu, L; Chen, F M; Wang, L; Zhang, P X; Jiang, X R

2016-04-18

To evaluate the meaning and value of high-frequency ultrasound in the diagnosis of carpal tunnel syndrome (CTS). In this study, 48 patients (unilateral hand) with CTS were analyzed. The thickness of transverse carpal ligaments at the pisiform bone was measured using high-frequency ultrasound. Open carpal tunnel release procedure was performed in the 48 CTS patients, and the thickness of transverse carpal ligaments at the hamate hook bone measured using vernier caliper under direct vision. The accuracy of thickness of transverse carpal ligaments was evaluated using high-frequency ultrasound. high-frequency ultrasound measurement of thickness of transverse carpal ligaments at the hamate hook bone and pisiform bone, and determination of the diagnostic threshold measurement index using receiver operating characteristic (ROC) curve, sensitivity and specificity were performed and the correlation between the thickness of transverse carpal ligaments and nerve conduction study (NCS) analyzed. The thickness of transverse carpal ligaments in the CTS patients were (0.42±0.08) cm (high-frequency ultrasound) and (0.41±0.06) cm (operation) at hamate hook bone, and there was no significant difference between the two ways (t=0.672, P>0.05). The optimal cut-off value of the transverse carpal ligaments at hamate hook bone was 0.385 cm, the sensitivity 0.775, and the specificity 0.788. The optimal cut-off value of the transverse carpal ligaments at the pisiform bone was 0.315 cm, the sensitivity 0.950, and the specificity 1.000. The transverse carpal ligaments thickness and wrist-index finger sensory nerve conduction velocity (SCV), wrist-middle finger SCV showed a negative correlation. High frequency ultrasound measurements of thickness of transverse carpal ligaments is a valuable method for the diagnosis of CTS.

26 CFR 1.1092(d)-2 - Personal property.

Code of Federal Regulations, 2010 CFR

2010-04-01

... principal holdings mimic the performance of the stocks included in the stock index (or alternatively a portfolio of stocks whose performance mimics the performance of the stocks included in the stock index). [T...

Some More Sensitive Measures of Sensitivity and Response Bias

NASA Technical Reports Server (NTRS)

Balakrishnan, J. D.

1998-01-01

In this article, the author proposes a new pair of sensitivity and response bias indices and compares them to other measures currently available, including d' and Beta of signal detection theory. Unlike d' and Beta, these new performance measures do not depend on specific distributional assumptions or assumptions about the transformation from stimulus information to a discrimination judgment with simulated and empirical data, the new sensitivity index is shown to be more accurate than d' and 16 other indices when these measures are used to compare the sensitivity levels of 2 experimental conditions. Results from a perceptual discrimination experiment demonstrate the feasibility of the new distribution-free bias index and suggest that biases of the type defined within the signal detection theory framework (i.e., the placement of a decision criterion) do not exist, even under an asymmetric payoff manipulation.

Facilitating access to information in large documents with an intelligent hypertext system

NASA Technical Reports Server (NTRS)

Mathe, Nathalie

1993-01-01

Retrieving specific information from large amounts of documentation is not an easy task. It could be facilitated if information relevant in the current problem solving context could be automatically supplied to the user. As a first step towards this goal, we have developed an intelligent hypertext system called CID (Computer Integrated Documentation) and tested it on the Space Station Freedom requirement documents. The CID system enables integration of various technical documents in a hypertext framework and includes an intelligent context-sensitive indexing and retrieval mechanism. This mechanism utilizes on-line user information requirements and relevance feedback either to reinforce current indexing in case of success or to generate new knowledge in case of failure. This allows the CID system to provide helpful responses, based on previous usage of the documentation, and to improve its performance over time.

NASA Video Catalog. Supplement 12

NASA Technical Reports Server (NTRS)

2002-01-01

This report lists 1878 video productions from the NASA STI Database. This issue of the NASA Video Catalog cites video productions listed in the NASA STI Database. The videos listed have been developed by the NASA centers, covering Shuttle mission press conferences; fly-bys of planets; aircraft design, testing and performance; environmental pollution; lunar and planetary exploration; and many other categories related to manned and unmanned space exploration. Each entry in the publication consists of a standard bibliographic citation accompanied by an abstract. The listing of the entries is arranged by STAR categories. A complete Table of Contents describes the scope of each category. For users with specific information, a Title Index is available. A Subject Term Index, based on the NASA Thesaurus, is also included. Guidelines for usage of NASA audio/visual material, ordering information, and order forms are also available.

Influence of the air’s refractive index on precision angle metrology with autocollimators

NASA Astrophysics Data System (ADS)

Geckeler, Ralf D.; Křen, Petr; Just, Andreas; Schumann, Matthias; Krause, Michael

2018-07-01

In this paper, we discuss a substantial—though previously neglected—error source in precision metrology with autocollimators, specifically, changes in the air’s refractive index, with a focus on the dominant impact of pressure changes. Pressure decreases with increasing elevation above sea level and is subject to substantial variation due to weather changes. It causes changes in an autocollimator’s angle response which are proportional to the measured angle and which increase linearly with the beam length and air pressure. We characterise this important influence in detail by using extended theoretical and experimental investigations and derive strategies for correcting it. We discuss its implications for the comparison of autocollimator calibrations performed at different metrology institutes which is crucial for validating their calibration capabilities. This work aims at approaching fundamental limits in angle metrology with autocollimators.

Specific absorption rate analysis of broadband mobile antenna with negative index metamaterial

NASA Astrophysics Data System (ADS)

Alam, Touhidul; Faruque, Mohammad Rashed Iqbal; Islam, Mohammad Tariqul

2016-03-01

This paper presents a negative index metamaterial-inspired printed mobile wireless antenna that can support most mobile applications such as GSM, UMTS, Bluetooth and WLAN frequency bands. The antenna consists of a semi-circular patch, a 50Ω microstrip feed line and metamaterial ground plane. The antenna occupies a very small space of 37 × 47 × 0.508 mm3, making it suitable for mobile wireless application. The perceptible novelty shown in this proposed antenna is that reduction of specific absorption rate using the negative index metamaterial ground plane. The proposed antenna reduced 72.11 and 75.53 % of specific absorption rate at 1.8 and 2.4 GHz, respectively.

Analysis and design of a standardized control module for switching regulators

NASA Astrophysics Data System (ADS)

Lee, F. C.; Mahmoud, M. F.; Yu, Y.; Kolecki, J. C.

1982-07-01

Three basic switching regulators: buck, boost, and buck/boost, employing a multiloop standardized control module (SCM) were characterized by a common small signal block diagram. Employing the unified model, regulator performances such as stability, audiosusceptibility, output impedance, and step load transient are analyzed and key performance indexes are expressed in simple analytical forms. More importantly, the performance characteristics of all three regulators are shown to enjoy common properties due to the unique SCM control scheme which nullifies the positive zero and provides adaptive compensation to the moving poles of the boost and buck/boost converters. This allows a simple unified design procedure to be devised for selecting the key SCM control parameters for an arbitrarily given power stage configuration and parameter values, such that all regulator performance specifications can be met and optimized concurrently in a single design attempt.

Braille character discrimination in blindfolded human subjects.

PubMed

Kauffman, Thomas; Théoret, Hugo; Pascual-Leone, Alvaro

2002-04-16

Visual deprivation may lead to enhanced performance in other sensory modalities. Whether this is the case in the tactile modality is controversial and may depend upon specific training and experience. We compared the performance of sighted subjects on a Braille character discrimination task to that of normal individuals blindfolded for a period of five days. Some participants in each group (blindfolded and sighted) received intensive Braille training to offset the effects of experience. Blindfolded subjects performed better than sighted subjects in the Braille discrimination task, irrespective of tactile training. For the left index finger, which had not been used in the formal Braille classes, blindfolding had no effect on performance while subjects who underwent tactile training outperformed non-stimulated participants. These results suggest that visual deprivation speeds up Braille learning and may be associated with behaviorally relevant neuroplastic changes.

Legal rights of client councils and their role in policy of long-term care organisations in the Netherlands

PubMed Central

2011-01-01

Background Legislation demands the establishment of client councils in Dutch nursing homes and residential care facilities. The members of those councils are residents or their representatives. Client councils have the right to participate in the strategic management of long-term care facilities. More specifically, they need to be consulted regarding organisational issues and a right to consent on issues regarding daily living of residents, including CQ-index research. CQ-index research concerns a method that measures, analyses and report clients' experiences about the quality of care. Research questions were: 'Do client councils exercise their rights to be consulted and to give their consent?' and 'What is the role of client councils in the process of measuring clients' experiences with the CQ-index and what is their opinion about the CQ-index?' Methods Postal questionnaires were sent to members of 1,540 client councils of Dutch nursing homes and residential care facilities. The questionnaire focussed on background information and client councils' involvement in decision-making and strategic management. Results The response rate was 34% (n = 524). Most councils consisted of seven members (range: 5 to 12 members). One out of four members participating in the client councils were clients themselves. Although councils have a legal right to be consulted for organisational issues like finance, vision, annual report, and accommodation, less than half the councils (31-46%) reported that they exercised this right. The legal right to consent was perceived by 18 to 36% of the councils regarding client care issues like food and drink, complaints registration, respectful treatment, and activities. For CQ-index research, only 18% of the client councils perceived a right to consent. Their rights to choose an approved contractor -who performs CQ-index research- and indicating improvement priorities, were hardly used. Conclusions Client councils play a rather passive role in determining the policy on quality of long-term care. Therefore, specific attention and actions are needed to create a more proactive attitude in councils towards exercising their rights, which are already supported by legislation. PMID:21910899

Muscle Weakness in the Empty and Full Can Tests Cannot Differentiate Rotator Cuff Tear from Cervical Spondylotic Amyotrophy: Pain Provocation is a Useful Finding.

PubMed

Iwata, Eiichiro; Shigematsu, Hideki; Inoue, Kazuya; Egawa, Takuya; Sakamoto, Yoshihiro; Tanaka, Yasuhito

2017-01-01

Rotator cuff tears and cervical spondylotic amyotrophy (CSA) are often confused as the main symptom in those with difficulty in shoulder elevation. Empty and full can tests are frequently used for the clinical diagnosis of rotator cuff tears. The aim of the present study was to investigate whether the empty and full can test results can help differentiate rotator cuff tears from CSA. Twenty-seven consecutive patients with rotator cuff tears and 25 with CSA were enrolled. We prospectively performed empty and full can tests in patients with rotator cuff tears and CSA. The following signs were considered positive: (a) muscle weakness during the empty can test, (b) muscle weakness during the full can test, (c) pain provocation during the empty can test, and (d) pain provocation during the full can test. We calculated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of rotator cuff tears for each positive finding. The sensitivity and specificity of each index were as follows (sensitivity, specificity, PPV, NPV): (a) 77.8%, 0%, 45.7%, 0%; (b) 66.7%, 4.0%, 42.9%, 10.0%; (c) 88.9%, 96.0%, 96.0%, 88.9%; and (d) 74.1%, 96.0%, 95.2%, 77.4%. There were significant differences for each index. Muscle weakness during the empty and full can tests was not useful in differentiating rotator cuff tears from CSA because of low specificity and PPV. However, pain provocation was useful in differentiating these two conditions because of high specificity and PPV.

Diagnostic accuracy of the aspartate aminotransferase-to-platelet ratio index for the prediction of hepatitis B-related fibrosis: a leading meta-analysis

PubMed Central

2012-01-01

Background The aspartate aminotransferase-to-platelet ratio index (APRI), a tool with limited expense and widespread availability, is a promising noninvasive alternative to liver biopsy for detecting hepatic fibrosis. The objective of this study was to systematically review the performance of the APRI in predicting significant fibrosis and cirrhosis in hepatitis B-related fibrosis. Methods Areas under summary receiver operating characteristic curves (AUROC), sensitivity and specificity were used to examine the accuracy of the APRI for the diagnosis of hepatitis B-related significant fibrosis and cirrhosis. Heterogeneity was explored using meta-regression. Results Nine studies were included in this meta-analysis (n = 1,798). Prevalence of significant fibrosis and cirrhosis were 53.1% and 13.5%, respectively. The summary AUCs of the APRI for significant fibrosis and cirrhosis were 0.79 and 0.75, respectively. For significant fibrosis, an APRI threshold of 0.5 was 84% sensitive and 41% specific. At the cutoff of 1.5, the summary sensitivity and specificity were 49% and 84%, respectively. For cirrhosis, an APRI threshold of 1.0-1.5 was 54% sensitive and 78% specific. At the cutoff of 2.0, the summary sensitivity and specificity were 28% and 87%, respectively. Meta-regression analysis indicated that the APRI accuracy for both significant fibrosis and cirrhosis was affected by histological classification systems, but not influenced by the interval between Biopsy & APRI or blind biopsy. Conclusion Our meta-analysis suggests that APRI show limited value in identifying hepatitis B-related significant fibrosis and cirrhosis. PMID:22333407

A training paradigm to enhance motor recovery in contused rats: effects of staircase training.

PubMed

Singh, Anita; Murray, Marion; Houle, John D

2011-01-01

Ambulating on stairs is an important aspect of daily activities for many individuals with incomplete spinal cord injury (SCI), and little is known about the effect of training for this specific task. The goal of this study was to determine whether staircase ascent training enhances motor recovery in animals with contusion injury. Rats received a midthoracic contusion lesion of moderate severity and were randomly divided into 2 groups, with one group receiving staircase ascent training for up to 8 weeks and the other receiving no training. To assess the direct effect of training, a task-specific staircase climbing test was performed. Open field test (BBB) and gait analysis (CatWalk) assessed overground recovery, and a grid test was used to assess improvement in sensorimotor tasks. Changes in muscle mass of the forelimb and hindlimb muscles were also measured, and the extent of spared white matter was determined for lesion verification and anatomical correlations. Staircase training improved the task-specific performance of ascent. Gait parameters, including base of support, stride length, regularity index (RI), and step sequence, also improved. Overground locomotion and the grid test, both showed a trend of improved performance. Finally, hindlimb muscle mass was maintained with training. Staircase ascent training after incomplete SCI has beneficial effects on task-specific as well as nonspecific motor and sensorimotor activities.

An automatic indexing method for medical documents.

PubMed Central

Wagner, M. M.

1991-01-01

This paper describes MetaIndex, an automatic indexing program that creates symbolic representations of documents for the purpose of document retrieval. MetaIndex uses a simple transition network parser to recognize a language that is derived from the set of main concepts in the Unified Medical Language System Metathesaurus (Meta-1). MetaIndex uses a hierarchy of medical concepts, also derived from Meta-1, to represent the content of documents. The goal of this approach is to improve document retrieval performance by better representation of documents. An evaluation method is described, and the performance of MetaIndex on the task of indexing the Slice of Life medical image collection is reported. PMID:1807564

Auto Indexer Auto-Indexer for Percussive Hammers: Vane Motor Dynamometer Testing

DOE Data Explorer

Su, Jiann

2012-01-01

Objectives Options associated with geothermal drilling operations are generally limited by factors such as formation temperature and rock strength. The objective of the research is to expand the "tool box" available to the geothermal driller by furthering the development of a high-temperature drilling motor that can be used in directional drilling applications for drilling high temperature geothermal formations. The motor is specifically designed to operate in conjunction with a pneumatic down-the-hole-hammer. It provides a more compact design compared to traditional drilling motors such as PDMs (positive displacement motors). The packaging can help to enhance directional drilling capabilities. It uses no elastomeric components, which enables it to operate in higher temperatures ( >250 °F). Current work on the motor has shown that is a capable of operating under pneumatic power with a down-the-hole-hammer. Further development work will include continued testing and refining motor components and evaluating motor capabilities. Targets/Milestones Complete testing current motor - 12/31/2010 Make final material and design decisions - 01/31/2011 Build and test final prototype - 04/31/2011 Final demonstration - 07/31/2011 Impacts The development of the motor will help to achieve program technical objectives by improving well construction capabilities. This includes enabling high-temperature drilling as well as enhancing directional drilling. A key component in the auto indexer is the drive motor. It is an air-driven vane motor that converts the energy stored in the compressed air to mechanical energy. The motor is attached to hammer-like components which impart an impulsive load onto the drive shaft. The impulsive force on the drive shaft in turn creates an indexing action. A controlled test was performed to characterize the performance of the the vane motor for a given pressure. The Sandia dynamometer test station was used to determine the performance of the motor for a given input pressure.

Do physical activity level and body mass index predict recovery from persistent neck pain in men and women of working age? A population-based cohort study.

PubMed

Rasmussen-Barr, E; Bohman, T; Hallqvist, J; Holm, L W; Skillgate, E

2013-09-01

The study sought to examine the gender-specific effects of physical activity level and body mass index on recovery from persistent neck pain (PNP) among citizens of working age in Stockholm, Sweden. A population-based cohort of 1,730 subjects (18-65) with PNP answered surveys in 2002 and 2007. Prognostic factors were self-reported body mass index (BMI) and physical activity level (PAL) at baseline. Analyses were performed with odds ratios (OR) with corresponding 95 % confidence intervals (95 % CI). Women reporting higher physical activity level had higher odds of recovering from PNP than women with sedentary leisure time (OR of 1.5, 95 % CI 1.0-2.4), but no associations were found in men. No associations were found between BMI and recovery from PNP in any analyses. Physical activity seems to be associated with recovery from PNP in women and should therefore be encouraged. Future studies should continue investigating physical activity and lifestyle factors in relation to recovery from persistent neck pain, since these modifiable factors may be considered in interventions.

A plea for the development of an universally accepted modular tooth wear evaluation system.

PubMed

Wetselaar, P; Faris, A; Lobbezoo, F

2016-11-03

Tooth wear is considered an increasing oral health problem. Due to its multifactorial nature, recognizing and diagnosing of tooth wear is difficult but nevertheless important. Over the years, a wide variety of evaluation systems has been developed, yet none of them is universally accepted. This has implications for both research and clinical practice. This paper describes an in-depth analysis of four commonly used tooth wear evaluation systems, namely, the Eccles index, the Tooth Wear Index, the Lussi index, and the Basic Erosive Wear Examination. Comparing those systems revealed that despite several similarities, they differ considerably from each other. Notably, all four systems have their specific advantages and disadvantages. However, neither one of them meets all necessary characteristics of a hypothetical, broadly applicable tooth wear evaluation system. In fact, it is not realistic that a single system qualifies for all purposes (for example, diagnosing or monitoring individual patients, performing epidemiological studies, etc.). As a potentially feasible solution for this issue, the development of an evaluation system is recommended that consists of multiple, coherent modules, which cover different purposes.

CCTV Coverage Index Based on Surveillance Resolution and Its Evaluation Using 3D Spatial Analysis

PubMed Central

Choi, Kyoungah; Lee, Impyeong

2015-01-01

We propose a novel approach to evaluating how effectively a closed circuit television (CCTV) system can monitor a targeted area. With 3D models of the target area and the camera parameters of the CCTV system, the approach produces surveillance coverage index, which is newly defined in this study as a quantitative measure for surveillance performance. This index indicates the proportion of the space being monitored with a sufficient resolution to the entire space of the target area. It is determined by computing surveillance resolution at every position and orientation, which indicates how closely a specific object can be monitored with a CCTV system. We present full mathematical derivation for the resolution, which depends on the location and orientation of the object as well as the geometric model of a camera. With the proposed approach, we quantitatively evaluated the surveillance coverage of a CCTV system in an underground parking area. Our evaluation process provided various quantitative-analysis results, compelling us to examine the design of the CCTV system prior to its installation and understand the surveillance capability of an existing CCTV system. PMID:26389909

Caucasian and Asian Specific Rheumatoid Arthritis Risk Loci Reveal Limited Replication and Apparent Allelic Heterogeneity in North Indians

PubMed Central

Prasad, Pushplata; Kumar, Ashok; Gupta, Rajiva; Juyal, Ramesh C.; B. K., Thelma

2012-01-01

Genome-wide association studies and meta-analysis indicate that several genes/loci are consistently associated with rheumatoid arthritis (RA) in European and Asian populations. To evaluate the transferability status of these findings to an ethnically diverse north Indian population, we performed a replication analysis. We investigated the association of 47 single-nucleotide polymorphisms (SNPs) at 43 of these genes/loci with RA in a north Indian cohort comprising 983 RA cases and 1007 age and gender matched controls. Genotyping was done using Infinium human 660w-quad. Association analysis by chi-square test implemented in plink was carried out in two steps. Firstly, association of the index or surrogate SNP (r2>0.8, calculated from reference GIH Hap-Map population) was tested. In the second step, evidence for allelic/locus heterogeneity at aforementioned genes/loci was assessed for by testing additional flanking SNPs in linkage equilibrium with index/surrogate marker. Of the 44 European specific index SNPs, neither index nor surrogate SNPs were present for nine SNPs in the genotyping array. Of the remaining 35, associations were replicated at seven genes namely PTPN22 (rs1217407, p = 3×10−3); IL2–21 (rs13119723, p = 0.008); HLA-DRB1 (rs660895, p = 2.56×10−5; rs6457617, p = 1.6×10−09; rs13192471, p = 6.7×10−16); TNFA1P3 (rs9321637, p = 0.03); CCL21 (rs13293020, p = 0.01); IL2RA (rs2104286, p = 1.9×10−4) and ZEB1 (rs2793108, p = 0.006). Of the three Asian specific loci tested, rs2977227 in PADI4 showed modest association (p<0.02). Further, of the 140 SNPs (in LE with index/surrogate variant) tested, association was observed at 11 additional genes: PTPRC, AFF3, CD28, CTLA4, PXK, ANKRD55, TAGAP, CCR6, BLK, CD40 and IL2RB. This study indicates limited replication of European and Asian index SNPs and apparent allelic heterogeneity in RA etiology among north Indians warranting independent GWAS in this population. However, replicated associations of HLA-DRB1, PTPN22 (which confer ∼50% of the heritable risk to RA) and IL2RA suggest that cross-ethnicity fine mapping of such loci is apposite for identification of causal variants. PMID:22355377

JPKWIC - General key word in context and subject index report generator

NASA Technical Reports Server (NTRS)

Jirka, R.; Kabashima, N.; Kelly, D.; Plesset, M.

1968-01-01

JPKWIC computer program is a general key word in context and subject index report generator specifically developed to help nonprogrammers and nontechnical personnel to use the computer to access files, libraries and mass documentation. This program is designed to produce a KWIC index, a subject index, an edit report, a summary report, and an exclusion list.

LACE+ index: extension of a validated index to predict early death or urgent readmission after hospital discharge using administrative data

PubMed Central

van Walraven, Carl; Wong, Jenna; Forster, Alan J

2012-01-01

Background Death or urgent readmission after hospital discharge is a common adverse event that can be used to compare outcomes of care between institutions. To accurately adjust for risk and to allow for interhospital comparisons of readmission rates, we used administrative data to derive and internally validate an extension of the LACE index, a previously validated index for 30-day death or urgent readmission. Methods We randomly selected 500 000 medical and surgical patients discharged to the community from any Ontario hospital between 1 April 2003 and 31 March 2009. We derived a logistic regression model on 250 000 randomly selected patients from this group and modified the final model into an index scoring system, the LACE+ index. We internally validated the LACE+ index using data from the remaining 250 000 patients and compared its performance with that of the original LACE index. Results Within 30 days of discharge to the community, 33 825 (6.8%) of the patients had died or had been urgently readmitted. In addition to the variables included in the LACE index (length of stay in hospital [L], acuity of admission [A], comorbidity [C] and emergency department utilization in the 6 months before admission [E]), the LACE+ index incorporated patient age and sex, teaching status of the discharge hospital, acute diagnoses and procedures performed during the index admission, number of days on alternative level of care during the index admission, and number of elective and urgent admissions to hospital in the year before the index admission. The LACE+ index was highly discriminative (C statistic 0.771, 95% confidence interval 0.767–0.775), was well calibrated across most of its range of scores and had a model performance that exceeded that of the LACE index. Interpretation The LACE+ index can be used to predict the risk of postdischarge death or urgent readmission on the basis of administrative data for the Ontario population. Its performance exceeds that of the LACE index, and it allows analysts to accurately estimate the risk of important postdischarge outcomes. PMID:23696773

Functional Roles of Neural Preparatory Processes in a Cued Stroop Task Revealed by Linking Electrophysiology with Behavioral Performance.

PubMed

Wang, Chao; Ding, Mingzhou; Kluger, Benzi M

2015-01-01

It is well established that cuing facilitates behavioral performance and that different aspects of instructional cues evoke specific neural preparatory processes in cued task-switching paradigms. To deduce the functional role of these neural preparatory processes the majority of studies vary aspects of the experimental paradigm and describe how these variations alter markers of neural preparatory processes. Although these studies provide important insights, they also have notable limitations, particularly in terms of understanding the causal or functional relationship of neural markers to cognitive and behavioral processes. In this study, we sought to address these limitations and uncover the functional roles of neural processes by examining how variability in the amplitude of neural preparatory processes predicts behavioral performance to subsequent stimuli. To achieve this objective 16 young adults were recruited to perform a cued Stroop task while their brain activity was measured using high-density electroencephalography. Four temporally overlapping but functionally and topographically distinct cue-triggered event related potentials (ERPs) were identified: 1) A left-frontotemporal negativity (250-700 ms) that was positively associated with word-reading performance; 2) a midline-frontal negativity (450-800 ms) that was positively associated with color-naming and incongruent performance; 3) a left-frontal negativity (450-800 ms) that was positively associated with switch trial performance; and 4) a centroparietal positivity (450-800 ms) that was positively associated with performance for almost all trial types. These results suggest that at least four dissociable cognitive processes are evoked by instructional cues in the present task, including: 1) domain-specific task facilitation; 2) switch-specific task-set reconfiguration; 3) preparation for response conflict; and 4) proactive attentional control. Examining the relationship between ERPs and behavioral performance provides a functional link between neural markers and the cognitive processes they index.

Context Specificity of Post-Error and Post-Conflict Cognitive Control Adjustments

PubMed Central

Forster, Sarah E.; Cho, Raymond Y.

2014-01-01

There has been accumulating evidence that cognitive control can be adaptively regulated by monitoring for processing conflict as an index of online control demands. However, it is not yet known whether top-down control mechanisms respond to processing conflict in a manner specific to the operative task context or confer a more generalized benefit. While previous studies have examined the taskset-specificity of conflict adaptation effects, yielding inconsistent results, control-related performance adjustments following errors have been largely overlooked. This gap in the literature underscores recent debate as to whether post-error performance represents a strategic, control-mediated mechanism or a nonstrategic consequence of attentional orienting. In the present study, evidence of generalized control following both high conflict correct trials and errors was explored in a task-switching paradigm. Conflict adaptation effects were not found to generalize across tasksets, despite a shared response set. In contrast, post-error slowing effects were found to extend to the inactive taskset and were predictive of enhanced post-error accuracy. In addition, post-error performance adjustments were found to persist for several trials and across multiple task switches, a finding inconsistent with attentional orienting accounts of post-error slowing. These findings indicate that error-related control adjustments confer a generalized performance benefit and suggest dissociable mechanisms of post-conflict and post-error control. PMID:24603900

Performance Evaluation of Machine Learning Methods for Leaf Area Index Retrieval from Time-Series MODIS Reflectance Data

PubMed Central

Wang, Tongtong; Xiao, Zhiqiang; Liu, Zhigang

2017-01-01

Leaf area index (LAI) is an important biophysical parameter and the retrieval of LAI from remote sensing data is the only feasible method for generating LAI products at regional and global scales. However, most LAI retrieval methods use satellite observations at a specific time to retrieve LAI. Because of the impacts of clouds and aerosols, the LAI products generated by these methods are spatially incomplete and temporally discontinuous, and thus they cannot meet the needs of practical applications. To generate high-quality LAI products, four machine learning algorithms, including back-propagation neutral network (BPNN), radial basis function networks (RBFNs), general regression neutral networks (GRNNs), and multi-output support vector regression (MSVR) are proposed to retrieve LAI from time-series Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data in this study and performance of these machine learning algorithms is evaluated. The results demonstrated that GRNNs, RBFNs, and MSVR exhibited low sensitivity to training sample size, whereas BPNN had high sensitivity. The four algorithms performed slightly better with red, near infrared (NIR), and short wave infrared (SWIR) bands than red and NIR bands, and the results were significantly better than those obtained using single band reflectance data (red or NIR). Regardless of band composition, GRNNs performed better than the other three methods. Among the four algorithms, BPNN required the least training time, whereas MSVR needed the most for any sample size. PMID:28045443

Performance Evaluation of Machine Learning Methods for Leaf Area Index Retrieval from Time-Series MODIS Reflectance Data.

PubMed

Wang, Tongtong; Xiao, Zhiqiang; Liu, Zhigang

2017-01-01

Leaf area index (LAI) is an important biophysical parameter and the retrieval of LAI from remote sensing data is the only feasible method for generating LAI products at regional and global scales. However, most LAI retrieval methods use satellite observations at a specific time to retrieve LAI. Because of the impacts of clouds and aerosols, the LAI products generated by these methods are spatially incomplete and temporally discontinuous, and thus they cannot meet the needs of practical applications. To generate high-quality LAI products, four machine learning algorithms, including back-propagation neutral network (BPNN), radial basis function networks (RBFNs), general regression neutral networks (GRNNs), and multi-output support vector regression (MSVR) are proposed to retrieve LAI from time-series Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data in this study and performance of these machine learning algorithms is evaluated. The results demonstrated that GRNNs, RBFNs, and MSVR exhibited low sensitivity to training sample size, whereas BPNN had high sensitivity. The four algorithms performed slightly better with red, near infrared (NIR), and short wave infrared (SWIR) bands than red and NIR bands, and the results were significantly better than those obtained using single band reflectance data (red or NIR). Regardless of band composition, GRNNs performed better than the other three methods. Among the four algorithms, BPNN required the least training time, whereas MSVR needed the most for any sample size.

Are we drunk yet? Motor versus cognitive cues of subjective intoxication.

PubMed

Celio, Mark A; Usala, Julie M; Lisman, Stephen A; Johansen, Gerard E; Vetter-O'Hagen, Courtney S; Spear, Linda P

2014-02-01

Perception of alcohol intoxication presumably plays an important role in guiding behavior during a current drinking episode. Yet, there has been surprisingly little investigation of what aspects associated with intoxication are used by individuals to attribute their level of intoxication. Building on recent laboratory-based findings, this study employed a complex field-based design to explore the relative contributions of motor performance versus cognitive performance-specifically executive control-on self-attributions of intoxication. Individuals recruited outside of bars (N = 280; mean age = 22; range: 18 to 32) completed a structured interview, self-report questionnaire, and neuropsychological testing battery, and provided a breath alcohol concentration (BrAC) sample. Results of a multiple linear regression analysis demonstrated that current level of subjective intoxication was associated with current alcohol-related stimulant effects, current sedative effects, and current BrAC. After controlling for the unique variance accounted for by these factors, subjective intoxication was better predicted by simple motor speed, as indexed by performance on the Finger Tapping Test, than by executive control, as indexed by performance on the Trail Making Test. These results-generated from data collected in a naturally occurring setting-support previous findings from a more traditional laboratory-based investigation, thus illustrating the iterative process of linking field methodology and controlled laboratory experimentation. Copyright © 2013 by the Research Society on Alcoholism.

Validation of the Combined Comorbidity Index of Charlson and Elixhauser to Predict 30-Day Mortality Across ICD-9 and ICD-10.

PubMed

Simard, Marc; Sirois, Caroline; Candas, Bernard

2018-05-01

To validate and compare performance of an International Classification of Diseases, tenth revision (ICD-10) version of a combined comorbidity index merging conditions of Charlson and Elixhauser measures against individual measures in the prediction of 30-day mortality. To select a weight derivation method providing optimal performance across ICD-9 and ICD-10 coding systems. Using 2 adult population-based cohorts of patients with hospital admissions in ICD-9 (2005, n=337,367) and ICD-10 (2011, n=348,820), we validated a combined comorbidity index by predicting 30-day mortality with logistic regression. To appreciate performance of the Combined index and both individual measures, factors impacting indices performance such as population characteristics and weight derivation methods were accounted for. We applied 3 scoring methods (Van Walraven, Schneeweiss, and Charlson) and determined which provides best predictive values. Combined index [c-statistics: 0.853 (95% confidence interval: CI, 0.848-0.856)] performed better than original Charlson [0.841 (95% CI, 0.835-0.844)] or Elixhauser [0.841 (95% CI, 0.837-0.844)] measures on ICD-10 cohort. All weight derivation methods provided close high discrimination results for the Combined index (Van Walraven: 0.852, Schneeweiss: 0.851, Charlson: 0.849). Results were consistent across both coding systems. The Combined index remains valid with both ICD-9 and ICD-10 coding systems and the 3 weight derivation methods evaluated provided consistent high performance across those coding systems.

Calibration of groundwater vulnerability mapping using the generalized reduced gradient method.

PubMed

Elçi, Alper

2017-12-01

Groundwater vulnerability assessment studies are essential in water resources management. Overlay-and-index methods such as DRASTIC are widely used for mapping of groundwater vulnerability, however, these methods mainly suffer from a subjective selection of model parameters. The objective of this study is to introduce a calibration procedure that results in a more accurate assessment of groundwater vulnerability. The improvement of the assessment is formulated as a parameter optimization problem using an objective function that is based on the correlation between actual groundwater contamination and vulnerability index values. The non-linear optimization problem is solved with the generalized-reduced-gradient (GRG) method, which is numerical algorithm based optimization method. To demonstrate the applicability of the procedure, a vulnerability map for the Tahtali stream basin is calibrated using nitrate concentration data. The calibration procedure is easy to implement and aims the maximization of correlation between observed pollutant concentrations and groundwater vulnerability index values. The influence of each vulnerability parameter in the calculation of the vulnerability index is assessed by performing a single-parameter sensitivity analysis. Results of the sensitivity analysis show that all factors are effective on the final vulnerability index. Calibration of the vulnerability map improves the correlation between index values and measured nitrate concentrations by 19%. The regression coefficient increases from 0.280 to 0.485. It is evident that the spatial distribution and the proportions of vulnerability class areas are significantly altered with the calibration process. Although the applicability of the calibration method is demonstrated on the DRASTIC model, the applicability of the approach is not specific to a certain model and can also be easily applied to other overlay-and-index methods. Copyright © 2017 Elsevier B.V. All rights reserved.

Calibration of groundwater vulnerability mapping using the generalized reduced gradient method

NASA Astrophysics Data System (ADS)

Elçi, Alper

2017-12-01

Groundwater vulnerability assessment studies are essential in water resources management. Overlay-and-index methods such as DRASTIC are widely used for mapping of groundwater vulnerability, however, these methods mainly suffer from a subjective selection of model parameters. The objective of this study is to introduce a calibration procedure that results in a more accurate assessment of groundwater vulnerability. The improvement of the assessment is formulated as a parameter optimization problem using an objective function that is based on the correlation between actual groundwater contamination and vulnerability index values. The non-linear optimization problem is solved with the generalized-reduced-gradient (GRG) method, which is numerical algorithm based optimization method. To demonstrate the applicability of the procedure, a vulnerability map for the Tahtali stream basin is calibrated using nitrate concentration data. The calibration procedure is easy to implement and aims the maximization of correlation between observed pollutant concentrations and groundwater vulnerability index values. The influence of each vulnerability parameter in the calculation of the vulnerability index is assessed by performing a single-parameter sensitivity analysis. Results of the sensitivity analysis show that all factors are effective on the final vulnerability index. Calibration of the vulnerability map improves the correlation between index values and measured nitrate concentrations by 19%. The regression coefficient increases from 0.280 to 0.485. It is evident that the spatial distribution and the proportions of vulnerability class areas are significantly altered with the calibration process. Although the applicability of the calibration method is demonstrated on the DRASTIC model, the applicability of the approach is not specific to a certain model and can also be easily applied to other overlay-and-index methods.

Physical activity is associated with changes in knee cartilage microstructure.

PubMed

Halilaj, E; Hastie, T J; Gold, G E; Delp, S L

2018-06-01

The purpose of this study was to determine if there is an association between objectively measured physical activity and longitudinal changes in knee cartilage microstructure. We used accelerometry and T 2 -weighted magnetic resonance imaging (MRI) data from the Osteoarthritis Initiative, restricting the analysis to men aged 45-60 years, with a body mass index (BMI) of 25-27 kg/m 2 and no radiographic evidence of knee osteoarthritis. After computing 4-year changes in mean T 2 relaxation time for six femoral cartilage regions and mean daily times spent in the sedentary, light, moderate, and vigorous activity ranges, we performed canonical correlation analysis (CCA) to find a linear combination of times spent in different activity intensity ranges (Activity Index) that was maximally correlated with a linear combination of regional changes in cartilage microstructure (Cartilage Microstructure Index). We used leave-one-out pre-validation to test the robustness of the model on new data. Nineteen subjects satisfied the inclusion criteria. CCA identified an Activity Index and a Cartilage Microstructure Index that were significantly correlated (r = .82, P < .0001 on test data). Higher levels of sedentary time and vigorous activity were associated with greater medial-lateral differences in longitudinal T 2 changes, whereas light activity was associated with smaller differences. Physical activity is better associated with an index that contrasts microstructural changes in different cartilage regions than it is with univariate or cumulative changes, likely because this index separates the effect of activity, which is greater in the medial loadbearing region, from that of patient-specific natural aging. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

The Diagnostic Value of the FIB-4 Index for Staging Hepatitis B-Related Fibrosis: A Meta-Analysis

PubMed Central

Li, Yuanyuan; Chen, Yu; Zhao, Ying

2014-01-01

Background Liver fibrosis stage is an important factor in determining prognosis and need for treatment in patients infected with hepatitis B virus (HBV). Liver biopsies are typically used to assess liver fibrosis; however, noninvasive alternatives such as the FIB-4 index have also been developed. Aims To quantify the accuracy of the FIB-4 index in the diagnosis of HBV related fibrosis and cirrhosis. Methods A meta-analysis of studies comparing the diagnostic accuracy of the FIB-4 index vs. liver biopsy in HBV-infected patients was performed using studies retrieved from the following databases: PubMed, Ovid, EMBASE, the Cochrane Library, the Chinese National Knowledge Infrastructure and the Chinese Biology Medicine disc. A hierarchical summary receiver operating curves model and bivariate model were used to produce summary receiver operating characteristic curves and pooled estimates of sensitivity and specificity. The heterogeneity was explored with meta-regression analysis. Publication bias was detected using Egger’s test and the trim and fill method. Results 12 studies (N = 1,908) and 10 studies (N = 2,105) were included in the meta-analysis for significant fibrosis and cirrhosis, respectively. For significant fibrosis, the area under the hierarchical summary receiver operating curve (AUHSROC) was 0.78 (95% CI = 0.74–0.81). The recommended cutoff value was between 1.45 and 1.62, and the AUHSROC, summary sensitivity and specificity were 0.78 (95% CI = 0.74–0.81), 0.65 (95% CI = 0.56–0.73) and 0.77 (95% CI = 0.7–0.83), respectively. For cirrhosis, the AUHSROC was 0.89 (95% CI = 0.85–0.91). The recommended cutoff value was between 2.9 and 3.6, and the AUHSROC, summary sensitivity and specificity were 0.96 (95% CI = 0.92–1.00), 0.42 (95% CI = 0.36–0.48) and 0.96 (95% CI = 0.95–0.97), respectively. No publication bias was detected. Conclusions The FIB-4 index is valuable for detecting significant fibrosis and cirrhosis in HBV-infected patients, but has suboptimal accuracy in excluding fibrosis and cirrhosis. PMID:25165830

Quantitative prediction of oral cancer risk in patients with oral leukoplakia.

PubMed

Liu, Yao; Li, Yicheng; Fu, Yue; Liu, Tong; Liu, Xiaoyong; Zhang, Xinyan; Fu, Jie; Guan, Xiaobing; Chen, Tong; Chen, Xiaoxin; Sun, Zheng

2017-07-11

Exfoliative cytology has been widely used for early diagnosis of oral squamous cell carcinoma. We have developed an oral cancer risk index using DNA index value to quantitatively assess cancer risk in patients with oral leukoplakia, but with limited success. In order to improve the performance of the risk index, we collected exfoliative cytology, histopathology, and clinical follow-up data from two independent cohorts of normal, leukoplakia and cancer subjects (training set and validation set). Peaks were defined on the basis of first derivatives with positives, and modern machine learning techniques were utilized to build statistical prediction models on the reconstructed data. Random forest was found to be the best model with high sensitivity (100%) and specificity (99.2%). Using the Peaks-Random Forest model, we constructed an index (OCRI2) as a quantitative measurement of cancer risk. Among 11 leukoplakia patients with an OCRI2 over 0.5, 4 (36.4%) developed cancer during follow-up (23 ± 20 months), whereas 3 (5.3%) of 57 leukoplakia patients with an OCRI2 less than 0.5 developed cancer (32 ± 31 months). OCRI2 is better than other methods in predicting oral squamous cell carcinoma during follow-up. In conclusion, we have developed an exfoliative cytology-based method for quantitative prediction of cancer risk in patients with oral leukoplakia.

An Evaluation of References to Indexes and Abstracts in Ulrich's 17th Edition.

ERIC Educational Resources Information Center

Wyndham, Diana

1980-01-01

Ulrich's performance in listing references to indexes was tested by comparing its statement of where a journal is indexed with the list of the indexed journals in the indexing/abstracting services themselves. (Author)

Single non-invasive model to diagnose non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH).

PubMed

Otgonsuren, Munkhzul; Estep, Michael J; Hossain, Nayeem; Younossi, Elena; Frost, Spencer; Henry, Linda; Hunt, Sharon; Fang, Yun; Goodman, Zachary; Younossi, Zobair M

2014-12-01

Non-alcoholic steatohepatitis (NASH) is the progressive form of non-alcoholic fatty liver disease (NAFLD). A liver biopsy is considered the "gold standard" for diagnosing/staging NASH. Identification of NAFLD/NASH using non-invasive tools is important for intervention. The study aims were to: develop/validate the predictive performance of a non-invasive model (index of NASH [ION]); assess the performance of a recognized non-invasive model (fatty liver index [FLI]) compared with ION for NAFLD diagnosis; determine which non-invasive model (FLI, ION, or NAFLD fibrosis score [NFS]) performed best in predicting age-adjusted mortality. From the National Health and Nutrition Examination Survey III database, anthropometric, clinical, ultrasound, laboratory, and mortality data were obtained (n = 4458; n = 861 [19.3%] NAFLD by ultrasound) and used to develop the ION model, and then to compare the ION and FLI models for NAFLD diagnosis. For validation and diagnosis of NASH, liver biopsy data were used (n = 152). Age-adjusted Cox proportional hazard modeling estimated the association among the three non-invasive tests (FLI, ION, and NFS) and mortality. FLI's threshold score > 60 and ION's threshold score > 22 had similar specificity (FLI = 80% vs ION = 82%) for NAFLD diagnosis; FLI < 30 (80% sensitivity) and ION < 11 (81% sensitivity) excluded NAFLD. An ION score > 50 predicted histological NASH (92% specificity); the FLI model did not predict NASH or mortality. The ION model was best in predicting cardiovascular/diabetes-related mortality; NFS predicted overall or diabetes-related mortality. The ION model was superior in predicting NASH and mortality compared with the FLI model. Studies are needed to validate ION. © 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

[Validation of cut points of skeletal muscle mass index for identifying sarcopenia in Chilean older people].

PubMed

Lera, Lydia; Ángel, Bárbara; Sánchez, Hugo; Picrin, Yaisy; Hormazabal, María José; Quiero, Andrea; Albala, Cecilia

2014-09-28

To estimate and validate cut-off points of skeletal muscle mass index (SMI) in Chilean population, for using in an algorithm for a diagnosis of sarcopenia developed by European Working Group on Sarcopenia in Older People (EWGSOP). Secondary analysis of Cross-sectional data in 440 Chilean older subjects to estimate cut-off points of SMI determined by DEXA and predicted by an anthropometric equation. Afterward a cross-sectional validation in a sample of 164 older people was performed. Anthropometric measures, self-reported health status, physical performance tests and DEXA were carried out. Decreased muscle strength was defined as handgrip strength <15 kg in women and <27 kg in male. Cut-off points of SMI were defined as values under 20th percentile for DEXA measures and estimated through ROC curves for the anthropometric model. Biological validity of the algorithm was tested by contrasting the diagnosis with physical performance tests and functionality. Cut-off points of SMI obtained by DEXA were 7.19 kg/m² in men and 5.77 kg/m² in women and 7.45 kg/ m² and 5.88 kg/m², respectively for the predicted by the model. Sensibility and specificity of estimations vs DEXA measures were 80% and 92% in men and 77% and 89% in women. We obtained cut-off points of SMI for DEXA and for a prediction equation for older adults Chilean, with good sensibility and specificity for the measurement by DEXA. It will allow to apply the EWGSOP algorithm to the early diagnosis of sarcopenia and to develop programs for prevention, delay or reversion this syndrome. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

An optimal search filter for retrieving systematic reviews and meta-analyses

PubMed Central

2012-01-01

Background Health-evidence.ca is an online registry of systematic reviews evaluating the effectiveness of public health interventions. Extensive searching of bibliographic databases is required to keep the registry up to date. However, search filters have been developed to assist in searching the extensive amount of published literature indexed. Search filters can be designed to find literature related to a certain subject (i.e. content-specific filter) or particular study designs (i.e. methodological filter). The objective of this paper is to describe the development and validation of the health-evidence.ca Systematic Review search filter and to compare its performance to other available systematic review filters. Methods This analysis of search filters was conducted in MEDLINE, EMBASE, and CINAHL. The performance of thirty-one search filters in total was assessed. A validation data set of 219 articles indexed between January 2004 and December 2005 was used to evaluate performance on sensitivity, specificity, precision and the number needed to read for each filter. Results Nineteen of 31 search filters were effective in retrieving a high level of relevant articles (sensitivity scores greater than 85%). The majority achieved a high degree of sensitivity at the expense of precision and yielded large result sets. The main advantage of the health-evidence.ca Systematic Review search filter in comparison to the other filters was that it maintained the same level of sensitivity while reducing the number of articles that needed to be screened. Conclusions The health-evidence.ca Systematic Review search filter is a useful tool for identifying published systematic reviews, with further screening to identify those evaluating the effectiveness of public health interventions. The filter that narrows the focus saves considerable time and resources during updates of this online resource, without sacrificing sensitivity. PMID:22512835

A Safety Index and Method for Flightdeck Evaluation

NASA Technical Reports Server (NTRS)

Latorella, Kara A.

2000-01-01

If our goal is to improve safety through machine, interface, and training design, then we must define a metric of flightdeck safety that is usable in the design process. Current measures associated with our notions of "good" pilot performance and ultimate safety of flightdeck performance fail to provide an adequate index of safe flightdeck performance for design evaluation purposes. The goal of this research effort is to devise a safety index and method that allows us to evaluate flightdeck performance holistically and in a naturalistic experiment. This paper uses Reason's model of accident causation (1990) as a basis for measuring safety, and proposes a relational database system and method for 1) defining a safety index of flightdeck performance, and 2) evaluating the "safety" afforded by flightdeck performance for the purpose of design iteration. Methodological considerations, limitations, and benefits are discussed as well as extensions to this work.

Primary mesenchymal (nonangiomatous/nonlymphomatous) neoplasms occurring in the canine spleen: anatomic classification, immunohistochemistry, and mitotic activity correlated with patient survival.

PubMed

Spangler, W L; Culbertson, M R; Kass, P H

1994-01-01

Surgical submissions from canine splenectomy cases spanning a 3-year period (1988-1990) were evaluated. Eighty seven neoplasms of the spleen considered to be of nonangiomatous and nonlymphomatous origin were selected for morphologic classification, mitotic index determination, immunohistochemical analysis, and patient survival determination. In 76/87 cases, patient survival information was available, and the mitotic index was determined in 83/87 cases. Immunohistochemistry for selected antigens (vimentin, desmin, smooth muscle actin, myosin, and factor VIII-related antigen) was performed in 58/87 of the cases. Morphologic classification of these lesions in standard HE preparations yielded the following neoplastic groups: fibrosarcoma (19/87), undifferentiated sarcoma (19/87), leiomyosarcoma (14/87), osteosarcoma (8/87), mesenchymoma (7/87), myxosarcoma (6/87), histiocytic sarcoma (6/87), leiomyoma (3/87), lipoma-myelolipoma (2/87), liposarcoma (2/87), and malignant fibrous histiocytoma (1/87). A lack of distinct morphologic characteristics among many of the neoplasms that were classified as either fibrosarcoma, leiomyosarcoma, or undifferentiated sarcoma contrasted these groups with the relatively unambiguous features that distinguished the other sarcoma groups. Using immunohistochemical staining for muscle-specific antigens (desmin, smooth muscle actin, and myosin), specific staining often overlapped extensively within the neoplastic groups of fibrosarcomas, leiomyosarcomas, and undifferentiated sarcomas, suggesting either ambiguous morphologic findings or the possibility of a common histogenesis from smooth muscle trabeculae or a distinct population of splenic myofibroblasts. The biological behavior of all tumors examined could be placed into three categories of patient survival: (1) benign, noninvasive tumors (leiomyoma, lipoma) with prolonged survival intervals; (2) malignant tumors (fibrosarcoma, undifferentiated sarcoma, leiomyosarcoma, osteosarcoma, myxosarcoma, histiocytic sarcoma, and liposarcoma), showing severely truncated survival (median 4 months with 80-100% mortality after 12 months; and (3) intermediate survival periods (median 12 months with 50% 1 year survival) attributed to a single group of neoplasm, the mesenchymomas. The biological behavior of primary splenic nonangiomatous, nonlymphomatous sarcomas was most closely correlated with observed mitotic index. Splenic neoplasms of this type with a mitotic index < 9 showed significantly (P < 0.0001) longer survival intervals than those with an index > 9. With the exception of osteosarcoma, all anatomically defined tumor groups contained one or more specimens with a mitotic index < 9. The clinical prognosis given for splenic sarcomas should be modified according to the mitotic index as a predictive value for patient survival.

Red blood cell membrane omega-3 fatty acid levels and physical performance: Cross-sectional data from the MAPT study.

PubMed

Fougère, Bertrand; de Souto Barreto, Philipe; Goisser, Sabine; Soriano, Gaëlle; Guyonnet, Sophie; Andrieu, Sandrine; Vellas, Bruno

2018-08-01

Studies have shown that omega-3 polyunsaturated fatty acids (PUFAs) are associated with brain, cardiovascular and immune function, as well as physical performance and bone health in older adults. So far, few studies have highlighted the associations between PUFA status and performance-based tests of physical function. To study the associations between the omega-3 index (red blood cell (RBC) membrane content of omega-3 PUFAs, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)) and physical performance measured with the Short Physical Performance Battery (SPPB) in a sample of community-dwelling older adults. Cross-sectional study using the baseline data of the Multidomain Alzheimer's Disease Trial (MAPT), a randomized, placebo-controlled trial. 1449 participants with available data on PUFAs were included. Omega-3 index and Short Physical Performance Battery (SPPB) scores were measured at enrollment and the omega-3 index expressed as the percentage of total fatty acid content was calculated. We also dichotomized the omega-3 index as low (lowest quartile) vs. high (three upper quartiles). Participants were 75.2 (±4.4) years old, 64.5% were female. Bivariate analyses found that participants who were in the lowest omega-3 index quartile (Q1) had a SPPB score significantly lower than participants in the three other quartiles (Q2-Q4). However, adjusted (for age, gender, cognitive function, depressive status, Body Mass Index and grip strength) multiple linear regression showed that the omega-3 index-SPPB score association did not reach statistical significance [β = -0.166; (-0.346; 0.013); p = 0.07] in our sample. This cross-sectional study found that participants with a low omega-3 index had worse performance-based test results of physical function than people with a high omega-3 index, but this association did not reach statistical significance once confounders were controlled for. Studies looking at the over-time associations between PUFA status and physical performance changes may shed more light on this topic. Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Photopolymer based VPHGs: from materials to sky results

NASA Astrophysics Data System (ADS)

Zanutta, A.; Orselli, E.; Fäcke, T.; Bianco, A.

2016-07-01

Volume Phase Holographic Gratings cover a relevant position as transmission dispersing elements in astronomical spectrographs and each astronomical observation could take advantage of specific dispersive elements with features tailored for achieving the best performances. The design and manufacturing of high efficiency and reliable VPHGs require photosensitive materials where it is possible to control both the refractive index modulation and the film thickness. By means of Bayfol® HX photopolymers, we designed and manufactured six VPHGs for astronomical instrumentation in a GRISM configuration. We demonstrated how photopolymers are reliable holographic materials for making astronomical VPHGs with performances comparable to those provided by VPHGs based on Dichromated Gelatins (DCGs), but with a much simpler production process.

Walker Branch Throughfall Displacement Experiment Data Report: Site Characterization, System Performance, Weather, Species Composition, and Growth (NDP-078 and 078A)

DOE Data Explorer

Cushman, Robert M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States), Carbon Dioxide Information Analysis Center, Environmental Sciences Division; Hanson, Paul J. [Oak Ridge National Laboratory, Oak Ridge, TN (USA), Environmental Sciences Division; Todd, Donald E. [Oak Ridge National Laboratory, Oak Ridge, TN (USA), Environmental Sciences Division; Riggs, Jeffery S. [Oak Ridge National Laboratory, Oak Ridge, TN (USA), Instrumentation and Controls Division; Wolfe, Mark E. [Tennessee Valley Authority, Norris, TN (USA); O'Neill, Elizabeth G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States), Environmental Sciences Division

2001-07-01

This numeric data package provides data sets, and accompanying documentation, on site characterization, system performance, weather, species composition, and growth for the Throughfall Displacement Experiment, which was established in the Walker Branch Watershed of East Tennessee to provide data on the responses of forests to altered precipitation regimes. The specific data sets include soil water content and potential, coarse fraction of the soil profile, litter layer temperature, soil temperature, monthly weather, daily weather, hourly weather, species composition of trees and saplings, mature tree and sapling annual growth, and relative leaf area index. Fortran and SAS(TM) access codes are provided to read the ASCII data files.

A novel methodology for querying web images

NASA Astrophysics Data System (ADS)

Prabhakara, Rashmi; Lee, Ching Cheng

2005-01-01

Ever since the advent of Internet, there has been an immense growth in the amount of image data that is available on the World Wide Web. With such a magnitude of image availability, an efficient and effective image retrieval system is required to make use of this information. This research presents an effective image matching and indexing technique that improvises on existing integrated image retrieval methods. The proposed technique follows a two-phase approach, integrating query by topic and query by example specification methods. The first phase consists of topic-based image retrieval using an improved text information retrieval (IR) technique that makes use of the structured format of HTML documents. It consists of a focused crawler that not only provides for the user to enter the keyword for the topic-based search but also, the scope in which the user wants to find the images. The second phase uses the query by example specification to perform a low-level content-based image match for the retrieval of smaller and relatively closer results of the example image. Information related to the image feature is automatically extracted from the query image by the image processing system. A technique that is not computationally intensive based on color feature is used to perform content-based matching of images. The main goal is to develop a functional image search and indexing system and to demonstrate that better retrieval results can be achieved with this proposed hybrid search technique.

A novel methodology for querying web images

NASA Astrophysics Data System (ADS)

Prabhakara, Rashmi; Lee, Ching Cheng

2004-12-01

Ever since the advent of Internet, there has been an immense growth in the amount of image data that is available on the World Wide Web. With such a magnitude of image availability, an efficient and effective image retrieval system is required to make use of this information. This research presents an effective image matching and indexing technique that improvises on existing integrated image retrieval methods. The proposed technique follows a two-phase approach, integrating query by topic and query by example specification methods. The first phase consists of topic-based image retrieval using an improved text information retrieval (IR) technique that makes use of the structured format of HTML documents. It consists of a focused crawler that not only provides for the user to enter the keyword for the topic-based search but also, the scope in which the user wants to find the images. The second phase uses the query by example specification to perform a low-level content-based image match for the retrieval of smaller and relatively closer results of the example image. Information related to the image feature is automatically extracted from the query image by the image processing system. A technique that is not computationally intensive based on color feature is used to perform content-based matching of images. The main goal is to develop a functional image search and indexing system and to demonstrate that better retrieval results can be achieved with this proposed hybrid search technique.

Reorganization of muscle activity in patients with chronic temporomandibular disorders.

PubMed

Mapelli, Andrea; Zanandréa Machado, Bárbara Cristina; Giglio, Lucia Dantas; Sforza, Chiarella; De Felício, Cláudia Maria

2016-12-01

To investigate whether reorganization of muscle activity occurs in patients with chronic temporomandibular disorders (TMD) and, if so, how it is affected by symptomatology severity. Surface electromyography (sEMG) of masticatory muscles was made in 30 chronic TMD patients, diagnosed with disc displacement with reduction (DDR) and pain. Two 15-patient subgroups, with moderate (TMDmo) and severe (TMDse) signs and symptoms, were compared with a control group of 15 healthy subjects matched by age. The experimental tasks were: a 5s inter-arch maximum voluntary clench (MVC); right and left 15s unilateral gum chewing tests. Standardized sEMG indices characterizing masseter and temporalis muscles activity were calculated, and a comprehensive functional index (FI) was introduced to quantitatively summarize subjects' overall performance. Mastication was also clinically evaluated. During MVC, TMDse patients had a significantly larger asymmetry of temporalis muscles contraction. Both TMD groups showed reduced coordination between masseter and temporalis muscles' maximal contraction, and their muscular activity distribution shifted significantly from masseter to temporalis muscles. During chewing, TMDse patients recruited the balancing side muscles proportionally more than controls, specifically the masseter muscle. When comparing right and left side chewing, the muscles' recruitment pattern resulted less symmetric in TMD patients, especially in TMDse. Overall, the functional index of both TMDmo and TMDse patients was significantly lower than that obtained by controls. Chronic TMD patients, specifically those with severe symptomatology, showed a reorganized activity, mainly resulting in worse functional performances. Copyright © 2016 Elsevier Ltd. All rights reserved.

Evaluation of left ventricular Tei index (index of myocardial performance) in healthy dogs and dogs with mitral regurgitation.

PubMed

Teshima, Kenji; Asano, Kazushi; Iwanaga, Koji; Koie, Hiroshi; Uechi, Masami; Kato, Yuka; Kutara, Kenji; Kanno, Nobuyuki; Seki, Mamiko; Edamura, Kazuya; Hasegawa, Atsuhiko; Tanaka, Shigeo

2007-02-01

The left ventricular (LV) Tei index (index of myocardial performance) has been demonstrated to be clinically useful in estimating comprehensive LV function, including the systolic and diastolic performances, in various human cardiac diseases. The purposes of this study were to validate the correlation between the LV Tei index and LV function obtained by cardiac catheterization in healthy dogs, and to evaluate the LV Tei index in dogs with naturally occurring mitral regurgitation (MR). In healthy dogs, the LV Tei index was significantly correlated with the LV peak +dP/dt (r = -0.89) and LV peak -dP/dt (r=0.87). The LV Tei index significantly increased in dogs with MR compared with normal dogs and significantly increased with progressively more severe clinical signs due to heart failure. The elevation of the LV Tei index in dogs with symptomatic MR appears to be associated with shortening of ejection time. The LV Tei index significantly increased with age and was not correlated with heart rate and body weight in normal dogs. In conclusion, our study demonstrated that the LV Tei index was measurable in dogs and not influenced by heart rate and body weight. The LV Tei index significantly increased with the progression of clinical signs in MR dogs. In particular, the elevation of the LV Tei index in dogs with symptomatic MR due to shortening of ejection time may suggest LV systolic dysfunction and the decrement of forward stroke volume.

Indexes of severity: conceptual development.

PubMed Central

Krischer, J P

1979-01-01

A discussion of severity index development is presented in relation to conceptual issues in index definition, analytic issues in index formulation and validation issues in index application. The CHOP index is discussed along with six severity indexes described in an earlier paper dealing with underlying concepts to illustrate the material presented. Replies are provided to specific questions raised in an accompanying paper discussing the Injury Severity Score. This conceptual material is presented to provide a foundation for severity index development, to suggest criteria to be used in their formulation and testing, and to identify analyses that can lead to the successful selection and application of an index for a defined purpose. PMID:468553

Multiple Myeloma Index for Risk of Infection.

PubMed

T, Valkovic; V, Gacic; A, Nacinovic-Duletic

2018-01-01

Based on our earlier research into the main characteristics and risk factors for infections in hospitalized patients with multiple myeloma, we created the numerical Multiple Myeloma Index for Risk of Infection (MMIRI) to predict infection in myeloma patients. The included factors that could influence the pathogenesis and incidence of infections were sex, performance status, Durie Salmon stage of disease, International Staging System, serum creatinine level, immune paresis, neutropenia, serum ferritin level, the presence of any catheters, disease duration, stable/progressive disease, and type of therapy. For each of these parameters, the strength of association with infection was statistically estimated and specific number of points was assigned to each of these parameters, proportional to the strength of the association. When designing the MMIRI, we included only those parameters that we determined were pathophysiologically associated with the infection. After further statistical analysis, we identified an optimal cutoff score of 6 or above as indicating a significant risk for infection, with a sensitivity of 93.2% and specificity of 80.2%. The scoring system in the retrospective receiver operating characteristic analysis showed an area under the curve of 0.918. The potential value of the MMIRI is the possibility of identifying those patients who would benefit from the prophylactic administration of antibiotics and other anti-infective measures while minimizing the contribution to antibiotic resistance related to the overuse of these drugs. As far as we know, this index represents the first attempt to create such an instrument for predicting the occurrence of infections in myeloma patients.

The Soil-Water Characteristic Curve of Unsaturated Tropical Residual Soil

NASA Astrophysics Data System (ADS)

Yusof, M. F.; Setapa, A. S.; Tajudin, S. A. A.; Madun, A.; Abidin, M. H. Z.; Marto, A.

2016-07-01

This study was conducted to determine the SWCC of unsaturated tropical residual soil in Kuala Lumpur, Malaysia. Undisturbed soil samples at five locations of high-risk slopes area were taken at a depth of 0.5 m using block sampler. In the determination of the SWCC, the pressure plate extractor with the capacity of 1500 kN/m2 has been used. The index properties of the soil such as natural moisture content, Atterberg limits, specific gravity, and soil classification are performed according to BS 1377: Part 2: 1990. The results of index properties show that the natural moisture content of the soil is between 36% to 46%, the plasticity index is between 10% - 26%, the specific gravity is between 2.51 - 2.61 and the soils is classified as silty organic clay of low plasticity. The SWCC data from the pressure plate extractor have been fitted with the Fredlund and Xing equation. The results show that the air entry value and residual matric suction for residual soils are in the range of 17 kN/m2 to 24 kN/m2 and 145 kN/m2 to 225 kN/m2 respectively. From the fitting curve, it is found that the average value of the Fredlund and Xing parameters such as a, n and m are in the range of 0.24-0.299, 1.7-4.8 and 0.142-0.440 respectively.

Involuntary Neuromuscular Coupling between the Thumb and Finger of Stroke Survivors during Dynamic Movement.

PubMed

Jones, Christopher L; Kamper, Derek G

2018-01-01

Finger-thumb coordination is crucial to manual dexterity but remains incompletely understood, particularly following neurological injury such as stroke. While being controlled independently, the index finger and thumb especially must work in concert to perform a variety of tasks requiring lateral or palmar pinch. The impact of stroke on this functionally critical sensorimotor control during dynamic tasks has been largely unexplored. In this study, we explored finger-thumb coupling during close-open pinching motions in stroke survivors with chronic hemiparesis. Two types of perturbations were applied randomly to the index with a novel Cable-Actuated Finger Exoskeleton: a sudden joint acceleration stretching muscle groups of the index finger and a sudden increase in impedance in selected index finger joint(s). Electromyographic signals for specific thumb and index finger muscles, thumb tip trajectory, and index finger joint angles were recorded during each trial. Joint angle perturbations invoked reflex responses in the flexor digitorum superficialis (FDS), first dorsal interossei (FDI), and extensor digitorum communis muscles of the index finger and heteronymous reflex responses in flexor pollicis brevis of the thumb ( p  < 0.017). Phase of movement played a role as a faster peak reflex response was observed in FDI during opening than during closing ( p  < 0.002) and direction of perturbations resulted in shorter reflex times for FDS and FDI ( p  < 0.012) for extension perturbations. Surprisingly, when index finger joint impedance was suddenly increased, thumb tip movement was substantially increased, from 2 to 10 cm ( p  < 0.001). A greater effect was seen during the opening phase ( p  < 0.044). Thus, involuntary finger-thumb coupling was present during dynamic movement, with perturbation of the index finger impacting thumb activity. The degree of coupling modulated with the phase of motion. These findings reveal a potential mechanism for direct intervention to improve poststroke hand mobility and provide insight on prospective neurologically oriented therapies.

Involuntary Neuromuscular Coupling between the Thumb and Finger of Stroke Survivors during Dynamic Movement

PubMed Central

Jones, Christopher L.; Kamper, Derek G.

2018-01-01

Finger–thumb coordination is crucial to manual dexterity but remains incompletely understood, particularly following neurological injury such as stroke. While being controlled independently, the index finger and thumb especially must work in concert to perform a variety of tasks requiring lateral or palmar pinch. The impact of stroke on this functionally critical sensorimotor control during dynamic tasks has been largely unexplored. In this study, we explored finger–thumb coupling during close–open pinching motions in stroke survivors with chronic hemiparesis. Two types of perturbations were applied randomly to the index with a novel Cable-Actuated Finger Exoskeleton: a sudden joint acceleration stretching muscle groups of the index finger and a sudden increase in impedance in selected index finger joint(s). Electromyographic signals for specific thumb and index finger muscles, thumb tip trajectory, and index finger joint angles were recorded during each trial. Joint angle perturbations invoked reflex responses in the flexor digitorum superficialis (FDS), first dorsal interossei (FDI), and extensor digitorum communis muscles of the index finger and heteronymous reflex responses in flexor pollicis brevis of the thumb (p < 0.017). Phase of movement played a role as a faster peak reflex response was observed in FDI during opening than during closing (p < 0.002) and direction of perturbations resulted in shorter reflex times for FDS and FDI (p < 0.012) for extension perturbations. Surprisingly, when index finger joint impedance was suddenly increased, thumb tip movement was substantially increased, from 2 to 10 cm (p < 0.001). A greater effect was seen during the opening phase (p < 0.044). Thus, involuntary finger–thumb coupling was present during dynamic movement, with perturbation of the index finger impacting thumb activity. The degree of coupling modulated with the phase of motion. These findings reveal a potential mechanism for direct intervention to improve poststroke hand mobility and provide insight on prospective neurologically oriented therapies. PMID:29545767

Three decades of disasters: a review of disaster-specific literature from 1977-2009.

PubMed

Smith, Erin; Wasiak, Jason; Sen, Ayan; Archer, Frank; Burkle, Frederick M

2009-01-01

The potential for disasters exists in all communities. To mitigate the potential catastrophes that confront humanity in the new millennium, an evidence-based approach to disaster management is required urgently. This study moves toward such an evidence-based approach by identifying peer-reviewed publications following a range of disasters and events over the past three decades. Peer-reviewed, event-specific literature was identified using a comprehensive search of the electronically indexed database, MEDLINE (1956-January 2009). An extended comprehensive search was conducted for one event to compare the event-specific literature indexed in MEDLINE to other electronic databases (EMBASE, CINAHL, AMED, CENTRAL, Psych Info, Maternity and Infant Care, EBM Reviews). Following 25 individual disasters or overwhelming crises, a total of 2,098 peer-reviewed, event-specific publications were published in 789 journals (652 publications following disasters/events caused by natural hazards, 966 following human-made/technological disasters/events, and 480 following conflict/complex humanitarian events).The event with the greatest number of peer-reviewed, event-specific publications was the 11 September 2001 terrorist attacks (686 publications). Prehospital and Disaster Medicine published the greatest number of peer-reviewed, event-specific publications (54), followed by Journal of Traumatic Stress (42), Military Medicine (40), and Psychiatric Services (40). The primary topics of event-specific publications were mental health, medical health, and response. When an extended, comprehensive search was conducted for one event, 75% of all peer-reviewed, event-specific publications were indexed in MEDLINE. A broad range of multi-disciplinary journals publish peer reviewed, event-specific publications. While the majority of peer-reviewed, event-specific literature is indexed in MEDLINE, comprehensive search strategies should include EMBASE to increase yield.

Leadership development practices and hospital financial outcomes.

PubMed

Crowe, Daniel; Garman, Andrew N; Li, Chien-Ching; Helton, Jeff; Anderson, Matthew M; Butler, Peter

2017-08-01

Affordable Care Act legislation is requiring leaders in US health systems to adapt to new and very different approaches to improving operating performance. Research from other industries suggests leadership development can be a helpful component of organizational change strategies; however, there is currently very little healthcare-specific research available to guide design and deployment. The goal of this exploratory study is to examine potential relationships between specific leadership development practices and health system financial outcomes. Results from the National Center for Healthcare Leadership survey of leadership development practices were correlated with hospital and health system financial performance data from the 2013 Medicare Cost Reports. A general linear regression model, controlling for payer mix, case-mix index, and bed size, was used to assess possible relationships between leadership practices and three financial performance metrics: operating margin, days cash on hand, and debt to capitalization. Statistically significant associations were found between hospital-level operating margins and 5 of the 11 leadership practices as well as the composite score. Relationships at the health system level, however, were not statistically significant. Results provide preliminary evidence of an association between hospital financial performance and investments made in developing their leaders.

Nouvelle methode d'optimisation du cout d'un vol par l'utilisation d'un systeme de gestion de vol et sa validation sur un avion Lockheed L-1011 TriStar

NASA Astrophysics Data System (ADS)

Gagne, Jocelyn

Usually, flights optimization and planning will take place before flight, on ground. However, it is not always feasible to do such optimization, or sometime unpredictable events may force pilots to change the flight path. In those circumstances, the pilots can only rely on charts or their Flight Management System (FMS) in order to maintain an economic flight. However, those FMS often rely on those same charts, which will not take into consideration different parameters, such as the cost index, the length on the flight or the weather. Even if some FMS take into consideration the weather, they may only rely on manually entered or limited data that could be outdated, insufficient or incomplete. The alleviate these problems, the function program's that was developed is mainly to determine the optimum flight profile for an aircraft, or more precisely, at the lowest overall cost, considering a take-off weight and weather conditions. The total cost is based on the value of time as well as the cost of fuel, resulting in the use of a ratio called the cost index. This index allows both to prioritize either the time or fuel consumption according to the costs related to a specific flight and/or airline. Thus, from a weight, the weather (wind, temperature, pressure), and the cost index, the program will calculate from the "Performance DataBase" (PDB) of a specific airplane an optimal flight profile over a given distance. The algorithm is based on linear interpolations in the performances tables using the Lagrange method. Moreover, in order to fully optimize the flight, the current program can, according to departure date and coordinates, download the latest available forecast from environment Canada website and calculate the optimum flight accordingly. The forecast data use by the program take the form of a 0.6 × 0.6 degrees grid in which the effects of wind, pressure and temperature are interpolated according to the aircraft geographical position and time. Using these tables, performances and forecasts, the program is therefore able to calculate the optimum profile from ground, but also in flight, if any change would occur on the path. Because all data is tabulated and not calculated, the required calculation power remains low, resulting in a short calculation time. Keywords: optimization, algorithm, simulation, cost.

Echocardiographic evaluation of diastolic functions in patients with polycystic ovary syndrome: A comperative study of diastolic functions in sub-phenotypes of polycystic ovary syndrome.

PubMed

Yildirim, Erkan; Karabulut, Onur; Yuksel, Uygar Cagdas; Celik, Murat; Bugan, Baris; Gokoglan, Yalcin; Ulubay, Mustafa; Gungor, Mutlu; Koklu, Mustafa

2017-01-01

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder among reproductive-aged women. It is known to be associated with cardiovascular diseases. The aim of this study was to determine and compare the echocardiographic data of patients according to the phenotypes of PCOS. This study included 113 patients with PCOS and 52 controls. Patients were classified into four potential PCOS phenotypes. Laboratory analyses and echocardiographic measurements were performed. Left ventricular mass was calculated by using Devereux formula and was indexed to body surface area. Phenotype-1 PCOS patients had significantly higher homeostasis model assessment - insu-lin resistance (HOMA-IR) (p = 0.023), free testosterone (p < 0.001), LDL cholesterol levels (p < 0.001) and free androgen index (p < 0.001) compared with the control group. There were significant differences between groups regarding the septal thickness, posterior wall thickness, Left ventricular ejection frac-tion, E/A ratio and left ventricular mass index (for all, p < 0.05). PCOS patients with phenotype 1 and 2 had significantly higher left ventricular mass index than the control group (p < 0.001). In univariate and multivariate analyses, PCOS phenotype, modified Ferriman-Gallwey Score and estradiol were found as variables, which independently could affect the left ventricular mass index. This study showed that women in their twenties who specifically fulfilled criteria for PCOS phenotype-1 according to the Rotterdam criteria, had higher left ventricular mass index and decreased E/A ratio, which might be suggestive of early stage diastolic dysfunction. (Cariol J 2017; 24, 4: 364-373).

Comparison between Surrogate Indexes of Insulin Sensitivity/Resistance and Hyperinsulinemic Euglycemic Glucose Clamps in Rhesus Monkeys

PubMed Central

Lee, Ho-Won; Muniyappa, Ranganath; Yan, Xu; Yue, Lilly Q.; Linden, Ellen H.; Chen, Hui; Hansen, Barbara C.

2011-01-01

The euglycemic glucose clamp is the reference method for assessing insulin sensitivity in humans and animals. However, clamps are ill-suited for large studies because of extensive requirements for cost, time, labor, and technical expertise. Simple surrogate indexes of insulin sensitivity/resistance including quantitative insulin-sensitivity check index (QUICKI) and homeostasis model assessment (HOMA) have been developed and validated in humans. However, validation studies of QUICKI and HOMA in both rats and mice suggest that differences in metabolic physiology between rodents and humans limit their value in rodents. Rhesus monkeys are a species more similar to humans than rodents. Therefore, in the present study, we evaluated data from 199 glucose clamp studies obtained from a large cohort of 86 monkeys with a broad range of insulin sensitivity. Data were used to evaluate simple surrogate indexes of insulin sensitivity/resistance (QUICKI, HOMA, Log HOMA, 1/HOMA, and 1/Fasting insulin) with respect to linear regression, predictive accuracy using a calibration model, and diagnostic performance using receiver operating characteristic. Most surrogates had modest linear correlations with SIClamp (r ≈ 0.4–0.64) with comparable correlation coefficients. Predictive accuracy determined by calibration model analysis demonstrated better predictive accuracy of QUICKI than HOMA and Log HOMA. Receiver operating characteristic analysis showed equivalent sensitivity and specificity of most surrogate indexes to detect insulin resistance. Thus, unlike in rodents but similar to humans, surrogate indexes of insulin sensitivity/resistance including QUICKI and log HOMA may be reasonable to use in large studies of rhesus monkeys where it may be impractical to conduct glucose clamp studies. PMID:21209021

Mental workload during brain-computer interface training.

PubMed

Felton, Elizabeth A; Williams, Justin C; Vanderheiden, Gregg C; Radwin, Robert G

2012-01-01

It is not well understood how people perceive the difficulty of performing brain-computer interface (BCI) tasks, which specific aspects of mental workload contribute the most, and whether there is a difference in perceived workload between participants who are able-bodied and disabled. This study evaluated mental workload using the NASA Task Load Index (TLX), a multi-dimensional rating procedure with six subscales: Mental Demands, Physical Demands, Temporal Demands, Performance, Effort, and Frustration. Able-bodied and motor disabled participants completed the survey after performing EEG-based BCI Fitts' law target acquisition and phrase spelling tasks. The NASA-TLX scores were similar for able-bodied and disabled participants. For example, overall workload scores (range 0-100) for 1D horizontal tasks were 48.5 (SD = 17.7) and 46.6 (SD 10.3), respectively. The TLX can be used to inform the design of BCIs that will have greater usability by evaluating subjective workload between BCI tasks, participant groups, and control modalities. Mental workload of brain-computer interfaces (BCI) can be evaluated with the NASA Task Load Index (TLX). The TLX is an effective tool for comparing subjective workload between BCI tasks, participant groups (able-bodied and disabled), and control modalities. The data can inform the design of BCIs that will have greater usability.

Validation of an obstetric comorbidity index in an external population.

PubMed

Metcalfe, A; Lix, L M; Johnson, J-A; Currie, G; Lyon, A W; Bernier, F; Tough, S C

2015-12-01

An obstetric comorbidity index has been developed recently with superior performance characteristics relative to general comorbidity measures in an obstetric population. This study aimed to externally validate this index and to examine the impact of including hospitalisation/delivery records only when estimating comorbidity prevalence and discriminative performance of the obstetric comorbidity index. Validation study. Alberta, Canada. Pregnant women who delivered a live or stillborn infant in hospital (n = 5995). Administrative databases were linked to create a population-based cohort. Comorbid conditions were identified from diagnoses for the delivery hospitalisation, all hospitalisations and all healthcare contacts (i.e. hospitalisations, emergency room visits and physician visits) that occurred during pregnancy and 3 months pre-conception. Logistic regression was used to test the discriminative performance of the comorbidity index. Maternal end-organ damage and extended length of stay for delivery. Although prevalence estimates for comorbid conditions were consistently lower in delivery records and hospitalisation data than in data for all healthcare contacts, the discriminative performance of the comorbidity index was constant for maternal end-organ damage [all healthcare contacts area under the receiver operating characteristic curve (AUC) = 0.70; hospitalisation data AUC = 0.67; delivery data AUC = 0.65] and extended length of stay for delivery (all healthcare contacts AUC = 0.60; hospitalisation data AUC = 0.58; delivery data AUC = 0.58). The obstetric comorbidity index shows similar performance characteristics in an external population and is a valid measure of comorbidity in an obstetric population. Furthermore, the discriminative performance of the comorbidity index was similar for comorbidities ascertained at the time of delivery, in hospitalisation data or through all healthcare contacts. © 2015 The Authors. BJOG An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd on behalf of Royal College of Obstetricians and Gynaecologists.

Performance Evaluation of Single Sideband Radio over Fiber System through Modulation Index Enhancement

NASA Astrophysics Data System (ADS)

Chen, Xiaogang; Hu, Xizhen; Huang, Dexiu

2014-09-01

The transmission performance of single sideband (SSB) radio over fiber (RoF) system is evaluated through tuning the modulation index of Mach-Zehnder modulator, two different data modulation schemes and the influence of fiber dispersion are considered. The quantitative simulation results validate that there exist an optimum modulation index, and the system performance could be improved if the data signal is modulated on only optical carrier or sidebands.

[Analysis of scientific production and bibliometric impact of a group of Spanish clinical researchers].

PubMed

Miró, O; Burbano Santos, P; Trilla, A; Casademont, J; Fernandez Pérez, C; Martín-Sánchez, Fj

2016-01-01

To study the behaviour of several indicators of scientific production and repercussion in a group of Spanish clinical researchers and to evaluate their possible utility for interpreting individual or collective scientific pathways. We performed a unicentric, ecological pilot study involving a group of physicians with consolidated research experience. From the Science Citation Index Expanded (SCI-Expanded) database, we obtained the number of publications of each author (indicator of production) and the number of citations, impact factor and h index (indicators of repercussion). These indicators were calculated individually for each of the years of research experience and we assessed the relationship between the experience of the researcher and the value of the indicator achieved, the relationship between these indicators themselves, and their temporal evolution, both individually and for the entire group. We analysed 35 researchers with a research experience of 28.4 (9.6) years. The h index showed the lowest coefficient of variance. The relationship between the indicators and research experience was significant, albeit modest (R2 between 0.15-0.22). The 4 indicators showed good correlations. The temporal evolution of the indicators, both individual and collective, adjusted better to a second grade polynomial than a linear function: individually, all the authors obtained R2>0.90 in all the indicators; together the best adjustment was produced with the h index (R2=0.61). Based on the indicator used, substantial variations may be produced in the researchers' ranking. A model of the temporal evolution of the indicators of production and repercussion can be described in a relatively homogeneous sample of researchers and the h index seems to demonstrate certain advantages compared to the remaining indicators. This type of analysis could become a predictive tool of performance to be achieved not only for a particular researcher, but also for a homogeneous group of resear-chers corresponding to a specific scientific niche.