Radioisotope identification method for poorly resolved gamma-ray spectrum of nuclear security concern

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

Ninh, Giang Nguyen; Phongphaeth, Pengvanich, E-mail: phongphaeth.p@chula.ac.th; Nares, Chankow

Gamma-ray signal can be used as a fingerprint for radioisotope identification. In the context of radioactive and nuclear materials security at the border control point, the detection task can present a significant challenge due to various constraints such as the limited measurement time, the shielding conditions, and the noise interference. This study proposes a novel method to identify the signal of one or several radioisotopes from a poorly resolved gamma-ray spectrum. In this method, the noise component in the raw spectrum is reduced by the wavelet decomposition approach, and the removal of the continuum background is performed using the baselinemore » determination algorithm. Finally, the identification of radioisotope is completed using the matrix linear regression method. The proposed method has been verified by experiments using the poorly resolved gamma-ray signals from various scenarios including single source, mixing of natural uranium with five of the most common industrial radioactive sources (57Co, 60Co, 133Ba, 137Cs, and 241Am). The preliminary results show that the proposed algorithm is comparable with the commercial method.« less

A metabolic way to investigate related hurdles causing poor bioavailability in oral delivery of isoacteoside in rats employing ultrahigh-performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry.

PubMed

Cui, Qingling; Pan, Yingni; Yan, Xiaowei; Qu, Bao; Liu, Xiaoqiu; Xiao, Wei

2017-02-28

Isoacteoside (ISAT), a phenylethanoid glycoside that acts as the principal bioactive component in traditional Chinese medicines, possesses broad pharmacological effects such as neuroprotective, antihypertensive and hepatoprotective activities. However, its pharmaceutical development has been severely limited due to the poor oral bioavailability. It is essential and significant to investigate related hurdles leading to the poor bioavailability of isoacteoside. Whole animal metabolism studies were conducted in rats, followed by metabolic mechanism including gastrointestinal stability, intestinal flora metabolism and intestinal enzyme metabolism employing the powerful method ultrahigh-performance liquid chromatography combined with quadrupole time-of-flight tandem mass spectrometry (UPLC/QTOF-MS/MS). A simple, rapid and sensitive method has been developed which comprehensively revealed the underlying cause of poor bioavailability of ISAT in a metabolic manner. The prototype of ISAT and its combined metabolites have not been detected in plasma. Furthermore, the residual content of the parent compound in in vitro experiments was approximately 59%, 5% and barely none in intestinal bacteria, intestinal S9 and simulated intestinal juice at 6 h, respectively. The present work has demonstrated that the factors causing the poor bioavailability of isoacteoside should be attributed to the metabolism. In general, the metabolism that resulted from intestinal flora and intestinal enzymes were predominant reasons giving rise to the poor bioavailability of ISAT, which also suggested that metabolites might be responsible for the excellent pharmacological effect of ISAT. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluating the ready biodegradability of two poorly water-soluble substances: comparative approach of bioavailability improvement methods (BIMs).

PubMed

Sweetlove, Cyril; Chenèble, Jean-Charles; Barthel, Yves; Boualam, Marc; L'Haridon, Jacques; Thouand, Gérald

2016-09-01

Difficulties encountered in estimating the biodegradation of poorly water-soluble substances are often linked to their limited bioavailability to microorganisms. Many original bioavailability improvement methods (BIMs) have been described, but no global approach was proposed for a standardized comparison of these. The latter would be a valuable tool as part of a wider strategy for evaluating poorly water-soluble substances. The purpose of this study was to define an evaluation strategy following the assessment of different BIMs adapted to poorly water-soluble substances with ready biodegradability tests. The study was performed with two poorly water-soluble chemicals-a solid, anthraquinone, and a liquid, isodecyl neopentanoate-and five BIMs were compared to the direct addition method (reference method), i.e., (i) ultrasonic dispersion, (ii) adsorption onto silica gel, (iii) dispersion using an emulsifier, (iv) dispersion with silicone oil, and (v) dispersion with emulsifier and silicone oil. A two-phase evaluation strategy of solid and liquid chemicals was developed involving the selection of the most relevant BIMs for enhancing the biodegradability of tested substances. A description is given of a BIM classification ratio (R BIM), which enables a comparison to be made between the different test chemical sample preparation methods used in the various tests. Thereby, using this comparison, the BIMs giving rise to the greatest biodegradability were ultrasonic dispersion and dispersion with silicone oil or with silicone oil and emulsifier for the tested solid chemical, adsorption onto silica gel, and ultrasonic dispersion for the liquid one.

The Impact of Hospital Size on CMS Hospital Profiling.

PubMed

Sosunov, Eugene A; Egorova, Natalia N; Lin, Hung-Mo; McCardle, Ken; Sharma, Vansh; Gelijns, Annetine C; Moskowitz, Alan J

2016-04-01

The Centers for Medicare & Medicaid Services (CMS) profile hospitals using a set of 30-day risk-standardized mortality and readmission rates as a basis for public reporting. These measures are affected by hospital patient volume, raising concerns about uniformity of standards applied to providers with different volumes. To quantitatively determine whether CMS uniformly profile hospitals that have equal performance levels but different volumes. Retrospective analysis of patient-level and hospital-level data using hierarchical logistic regression models with hospital random effects. Simulation of samples including a subset of hospitals with different volumes but equal poor performance (hospital effects=+3 SD in random-effect logistic model). A total of 1,085,568 Medicare fee-for-service patients undergoing 1,494,993 heart failure admissions in 4930 hospitals between July 1, 2005 and June 30, 2008. CMS methodology was used to determine the rank and proportion (by volume) of hospitals reported to perform "Worse than US National Rate." Percent of hospitals performing "Worse than US National Rate" was ∼40 times higher in the largest (fifth quintile by volume) compared with the smallest hospitals (first quintile). A similar gradient was seen in a cohort of 100 hospitals with simulated equal poor performance (0%, 0%, 5%, 20%, and 85% in quintiles 1 to 5) effectively leaving 78% of poor performers undetected. Our results illustrate the disparity of impact that the current CMS method of hospital profiling has on hospitals with higher volumes, translating into lower thresholds for detection and reporting of poor performance.

A probabilistic and multi-objective analysis of lexicase selection and ε-lexicase selection.

PubMed

Cava, William La; Helmuth, Thomas; Spector, Lee; Moore, Jason H

2018-05-10

Lexicase selection is a parent selection method that considers training cases individually, rather than in aggregate, when performing parent selection. Whereas previous work has demonstrated the ability of lexicase selection to solve difficult problems in program synthesis and symbolic regression, the central goal of this paper is to develop the theoretical underpinnings that explain its performance. To this end, we derive an analytical formula that gives the expected probabilities of selection under lexicase selection, given a population and its behavior. In addition, we expand upon the relation of lexicase selection to many-objective optimization methods to describe the behavior of lexicase selection, which is to select individuals on the boundaries of Pareto fronts in high-dimensional space. We show analytically why lexicase selection performs more poorly for certain sizes of population and training cases, and show why it has been shown to perform more poorly in continuous error spaces. To address this last concern, we propose new variants of ε-lexicase selection, a method that modifies the pass condition in lexicase selection to allow near-elite individuals to pass cases, thereby improving selection performance with continuous errors. We show that ε-lexicase outperforms several diversity-maintenance strategies on a number of real-world and synthetic regression problems.

Benchmarking routine psychological services: a discussion of challenges and methods.

PubMed

Delgadillo, Jaime; McMillan, Dean; Leach, Chris; Lucock, Mike; Gilbody, Simon; Wood, Nick

2014-01-01

Policy developments in recent years have led to important changes in the level of access to evidence-based psychological treatments. Several methods have been used to investigate the effectiveness of these treatments in routine care, with different approaches to outcome definition and data analysis. To present a review of challenges and methods for the evaluation of evidence-based treatments delivered in routine mental healthcare. This is followed by a case example of a benchmarking method applied in primary care. High, average and poor performance benchmarks were calculated through a meta-analysis of published data from services working under the Improving Access to Psychological Therapies (IAPT) Programme in England. Pre-post treatment effect sizes (ES) and confidence intervals were estimated to illustrate a benchmarking method enabling services to evaluate routine clinical outcomes. High, average and poor performance ES for routine IAPT services were estimated to be 0.91, 0.73 and 0.46 for depression (using PHQ-9) and 1.02, 0.78 and 0.52 for anxiety (using GAD-7). Data from one specific IAPT service exemplify how to evaluate and contextualize routine clinical performance against these benchmarks. The main contribution of this report is to summarize key recommendations for the selection of an adequate set of psychometric measures, the operational definition of outcomes, and the statistical evaluation of clinical performance. A benchmarking method is also presented, which may enable a robust evaluation of clinical performance against national benchmarks. Some limitations concerned significant heterogeneity among data sources, and wide variations in ES and data completeness.

Study Methods for Improving Quality Learning and Performance in Higher Education

ERIC Educational Resources Information Center

Mutsotso, S. N.; Abenga, E. S. B.

2010-01-01

Education is an investment to development and poor study methods should not compromise the mandate of higher education institutions to generate, preserve and disseminate knowledge and produce high quality graduates. Universities admit students with varying backgrounds in terms of learning/study styles, levels of preparedness and concepts of…

Medical adherence to acne therapy: a systematic review.

PubMed

Snyder, Stephanie; Crandell, Ian; Davis, Scott A; Feldman, Steven R

2014-04-01

Poor adherence of acne patients to treatment may equate to poor clinical efficacy, increased healthcare costs, and unnecessary treatments. Authors have investigated risk factors for poor medical adherence and how to improve this difficult problem in the context of acne. This systematic review aims to describe what methods have been used to measure adherence, what is known about acne patients' adherence to treatment, and the factors affecting adherence. A MEDLINE search was performed for randomized controlled trials published between 1978 and June 2013, focusing on patient adherence to prescribed acne medications. A test for equality of proportions was performed on studies of similar design to collectively analyze adherence to oral versus topical medication. The self-reported adherence data collected from these clinical trials were then compared with adherence data from a pharmacy database study. Studies varied in modalities of data collection, but the majority utilized subjective methods. Topical therapies were more often studied than oral. The overall oral adherence rate, as calculated by a test of equality of proportions, was 76.3%, while the overall topical adherence rate was 75.8% (p=0.927). The occurrence of side effects and young age were cited as the top reasons for poor adherence, followed by forgetfulness. The MEDLINE search resulted in a limited sample of adherence studies. In addition, there is currently no standardized or fully validated method of measurement, allowing for variability in what was considered 'adherent'. Lastly, data collected via subjective methods cannot guarantee reliable results. Overall, the values reflected a population adherent to both topical and oral medications, with no significant difference in adherence between the two. However, the methodologies used by many of the studies were weak, and the findings are not consistent with results of more objective measures of adherence. The leading factors that contribute to poor adherence may be reduced with enhanced patient consultation, reminder systems, and education.

A simple strategy to reduce stereotype threat for orthopedic residents

PubMed Central

Gomez, Everlyne; Wright, James G.

2014-01-01

Background Stereotype threat, defined as the predicament felt by people in either positive or negative learning experiences where they could conform to negative stereotypes associated with their own group membership, can interfere with learning. The purpose of this study was to determine if a simple orientation session could reduce stereotype threat for orthopedic residents. Methods The intervention group received an orientation on 2 occasions focusing on their possible responses to perceived poor performance in teaching rounds and the operating room (OR). Participants completed a survey with 7 questions typical for stereotype threat evaluating responses to their experiences. The questions had 7 response options with a maximum total score of 49, where higher scores indicated greater degree of experiences typical of stereotype threat. Results Of the 84 eligible residents, 49 participated: 22 in the nonintervention and 27 in the intervention group. The overall scores were 29 and 29.4, and 26.2 and 25.8 in the nonintervention and intervention groups for their survey responses to perceived poor performance in teaching rounds (p = 0.85) and the OR (p = 0.84), respectively. Overall, responses typical of stereotype threat were greater for perceived poor performance at teaching rounds than in the OR (p = 0.001). Conclusion Residents experience low self-esteem following perceived poor performance, particularly at rounds. A simple orientation designed to reduce stereotype threat was unsuccessful in reducing this threat overall. Future research will need to consider longer-term intervention as possible strategies to reduce perceived poor performance at teaching rounds and in the OR. PMID:24666454

Poor Performance Among Trainees in a Dutch Postgraduate GP Training Program.

PubMed

Vermeulen, Margit I; Kuyvenhoven, Marijke M; de Groot, Esther; Zuithoff, Nicolaas Pa; Pieters, Honore M; van der Graaf, Yolanda; Damoiseaux, Roger Amj

2016-06-01

Poor performance among trainees is an important issue, for patient safety and economic reasons. While early identification might enhance remediation measures, we explored the frequency, nature, and risk factors of poor performance in a Dutch postgraduate general practitioner (GP) training program. All trainees who started the GP training between 2005 and 2007 were included. Multivariate logistic regression analysis was applied to examine associations between individual characteristics; early assessments of competencies and knowledge, training process characteristics (eg, illness, maternal leave), and the outcome poor performance; sub-analyses were performed for each year. A total of 215 trainees started the 3-year GP program, and 49 (22.8%) exhibited poor performance (in one or more years). In the first and second years, problem areas among poor performers were equally distributed across the roles of "medical expert," "communicator," and "professional." In the third year, shortcomings in "professionalism" were the most common problem. Increasing age was a risk factor for poor performance as were insufficient scores in communication and knowledge. Poor performance in the previous year was a risk factor for poor performance in the second and third years; OR=4.20 (CI=1.31--13.47) and OR=5.40 (CI=1.58--18.47), respectively. Poor performance is prevalent but primarily occurring within a single training year. This finding suggests that trainees are capable of solving trainee problems. Increasing age, insufficient assessment scores early in the training, and poor performance in a previous year constitute risk factors for poor performance.

All Plasma Products Are Not Created Equal: Characterizing Differences Between Plasma Products

DTIC Science & Technology

2015-06-01

2011;6(4):e18812. 24. Chandler WL. Microparticle counts in platelet - rich and platelet -free plasma , effect of centrifugation and sample-processing protocols...used throughout the article for this product. Laboratory Methods Platelet -Poor Plasma Preparation Platelet -poor plasma (PPP) was prepared by centrifuga... platelets , respectively. Flow cytometry was performed as described by Matijevic et al.4 Briefly, 10 KL of each plasma product was incubated with

Binarization of Gray-Scaled Digital Images Via Fuzzy Reasoning

NASA Technical Reports Server (NTRS)

Dominquez, Jesus A.; Klinko, Steve; Voska, Ned (Technical Monitor)

2002-01-01

A new fast-computational technique based on fuzzy entropy measure has been developed to find an optimal binary image threshold. In this method, the image pixel membership functions are dependent on the threshold value and reflect the distribution of pixel values in two classes; thus, this technique minimizes the classification error. This new method is compared with two of the best-known threshold selection techniques, Otsu and Huang-Wang. The performance of the proposed method supersedes the performance of Huang- Wang and Otsu methods when the image consists of textured background and poor printing quality. The three methods perform well but yield different binarization approaches if the background and foreground of the image have well-separated gray-level ranges.

Binarization of Gray-Scaled Digital Images Via Fuzzy Reasoning

NASA Technical Reports Server (NTRS)

Dominquez, Jesus A.; Klinko, Steve; Voska, Ned (Technical Monitor)

2002-01-01

A new fast-computational technique based on fuzzy entropy measure has been developed to find an optimal binary image threshold. In this method, the image pixel membership functions are dependent on the threshold value and reflect the distribution of pixel values in two classes; thus, this technique minimizes the classification error. This new method is compared with two of the best-known threshold selection techniques, Otsu and Huang-Wang. The performance of the proposed method supersedes the performance of Huang-Wang and Otsu methods when the image consists of textured background and poor printing quality. The three methods perform well but yield different binarization approaches if the background and foreground of the image have well-separated gray-level ranges.

Perfectionism related to self-reported insomnia severity, but not when controlled for stress and emotion regulation

PubMed Central

Brand, Serge; Kirov, Roumen; Kalak, Nadeem; Gerber, Markus; Pühse, Uwe; Lemola, Sakari; Correll, Christoph U; Cortese, Samuele; Meyer, Till; Holsboer-Trachsler, Edith

2015-01-01

Background Perfectionism is understood as a set of personality traits such as unrealistically high and rigid standards for performance, fear of failure, and excessive self-criticism. Previous studies showed a direct association between increased perfectionism and poor sleep, though without taking into account possible mediating factors. Here, we tested the hypothesis that perfectionism was directly associated with poor sleep, and that this association collapsed, if mediating factors such as stress and poor emotion regulation were taken into account. Methods Three hundred and forty six young adult students (M=23.87 years) completed questionnaires relating to perfectionism traits, sleep, and psychological functioning such as stress perception, coping with stress, emotion regulation, and mental toughness. Results Perfectionism was directly associated with poor sleep and poor psychological functioning. When stress, poor coping, and poor emotion regulation were entered in the equation, perfectionism traits no longer contributed substantively to the explanation of poor sleep. Conclusion Though perfectionism traits seem associated with poor sleep, the direct role of such traits seemed small, when mediating factors such as stress perception and emotion regulation were taken into account. PMID:25678791

Counter traction makes endoscopic submucosal dissection easier.

PubMed

Oyama, Tsuneo

2012-11-01

Poor counter traction and poor field of vision make endoscopic submucosal dissection (ESD) difficult. Good counter traction allows dissections to be performed more quickly and safely. Position change, which utilizes gravity, is the simplest method to create a clear field of vision. It is useful especially for esophageal and colon ESD. The second easiest method is clip with line method. Counter traction made by clip with line accomplishes the creation of a clear field of vision and suitable counter traction thereby making ESD more efficient and safe. The author published this method in 2002. The name ESD was not established in those days; the name cutting endoscopic mucosal resection (EMR) or EMR with hook knife was used. The other traction methods such as external grasping forceps, internal traction, double channel scope, and double scopes method are introduced in this paper. A good strategy for creating counter traction makes ESD easier.

Changes in Examination Performance in English Secondary Schools over the Course of a Decade: Searching for Patterns and Trends over Time

ERIC Educational Resources Information Center

Mangan, Jean; Pugh, Geoff; Gray, John

2005-01-01

The article explores changes in the examination performance of a random sample of 500 English secondary schools between 1992 and 2001. Using econometric methods, it concludes that: there is an overall deterministic trend in school performance but it is not stable, making prediction accuracy poor; the aggregate trend does not explain improvement…

A framework for streamflow prediction in the world's most severely data-limited regions: Test of applicability and performance in a poorly-gauged region of China

NASA Astrophysics Data System (ADS)

Alipour, M. H.; Kibler, Kelly M.

2018-02-01

A framework methodology is proposed for streamflow prediction in poorly-gauged rivers located within large-scale regions of sparse hydrometeorologic observation. A multi-criteria model evaluation is developed to select models that balance runoff efficiency with selection of accurate parameter values. Sparse observed data are supplemented by uncertain or low-resolution information, incorporated as 'soft' data, to estimate parameter values a priori. Model performance is tested in two catchments within a data-poor region of southwestern China, and results are compared to models selected using alternative calibration methods. While all models perform consistently with respect to runoff efficiency (NSE range of 0.67-0.78), models selected using the proposed multi-objective method may incorporate more representative parameter values than those selected by traditional calibration. Notably, parameter values estimated by the proposed method resonate with direct estimates of catchment subsurface storage capacity (parameter residuals of 20 and 61 mm for maximum soil moisture capacity (Cmax), and 0.91 and 0.48 for soil moisture distribution shape factor (B); where a parameter residual is equal to the centroid of a soft parameter value minus the calibrated parameter value). A model more traditionally calibrated to observed data only (single-objective model) estimates a much lower soil moisture capacity (residuals of Cmax = 475 and 518 mm and B = 1.24 and 0.7). A constrained single-objective model also underestimates maximum soil moisture capacity relative to a priori estimates (residuals of Cmax = 246 and 289 mm). The proposed method may allow managers to more confidently transfer calibrated models to ungauged catchments for streamflow predictions, even in the world's most data-limited regions.

Conflict Management.

ERIC Educational Resources Information Center

Fisher, William; Koue, Glen

1991-01-01

Discusses general issues involved in conflict management and provides more specific examples of conflict management in libraries. Causes of conflict are considered, including organizational structure, departmentalization, performance appraisal, poor communication, and technological change; and methods of dealing with conflict are described,…

Toward the establishment of standardized in vitro tests for lipid-based formulations, part 1: method parameterization and comparison of in vitro digestion profiles across a range of representative formulations.

PubMed

Williams, Hywel D; Sassene, Philip; Kleberg, Karen; Bakala-N'Goma, Jean-Claude; Calderone, Marilyn; Jannin, Vincent; Igonin, Annabel; Partheil, Anette; Marchaud, Delphine; Jule, Eduardo; Vertommen, Jan; Maio, Mario; Blundell, Ross; Benameur, Hassan; Carrière, Frédéric; Müllertz, Anette; Porter, Christopher J H; Pouton, Colin W

2012-09-01

The Lipid Formulation Classification System Consortium is an industry-academia collaboration, established to develop standardized in vitro methods for the assessment of lipid-based formulations (LBFs). In this first publication, baseline conditions for the conduct of digestion tests are suggested and a series of eight model LBFs are described to probe test performance across different formulation types. Digestion experiments were performed in vitro using a pH-stat apparatus and danazol employed as a model poorly water-soluble drug. LBF digestion (rate and extent) and drug solubilization patterns on digestion were examined. To evaluate cross-site reproducibility, experiments were conducted at two sites and highly consistent results were obtained. In a further refinement, bench-top centrifugation was explored as a higher throughput approach to separation of the products of digestion (and compared with ultracentrifugation), and conditions under which this method was acceptable were defined. Drug solubilization was highly dependent on LBF composition, but poorly correlated with simple performance indicators such as dispersion efficiency, confirming the utility of the digestion model as a means of formulation differentiation. Copyright © 2012 Wiley Periodicals, Inc.

From approach to inhibition: the influence of power on responses to poor performers.

PubMed

Ferguson, Amanda J; Ormiston, Margaret E; Moon, Henry

2010-03-01

This article examines how relative differences in power affect responses to poor performers in organizations. We predicted that higher power individuals would engage in approach-related behaviors, whereas lower power individuals would be inhibited when responding to poor performers. Results from a scenario study and a field study generally supported this prediction, indicating that power was positively related to training or confronting a poor performer and negatively related to compensating for or rejecting a poor performer. A second scenario study investigated the effect of the interaction of power and emotion on individual responses to poor performers. Results showed that the type of emotion expressed moderated the effect of power on inhibition-related responses. We discuss implications for managing poor performers with relative power differences. 2010 APA, all rights reserved

Preservation and compensation: The functional neuroanatomy of insight and working memory in schizophrenia☆

PubMed Central

Sapara, Adegboyega; ffytche, Dominic H.; Birchwood, Max; Cooke, Michael A.; Fannon, Dominic; Williams, Steven C.R.; Kuipers, Elizabeth; Kumari, Veena

2014-01-01

Background Poor insight in schizophrenia has been theorised to reflect a cognitive deficit that is secondary to brain abnormalities, localized in the brain regions that are implicated in higher order cognitive functions, including working memory (WM). This study investigated WM-related neural substrates of preserved and poor insight in schizophrenia. Method Forty stable schizophrenia outpatients, 20 with preserved and 20 with poor insight (usable data obtained from 18 preserved and 14 poor insight patients), and 20 healthy participants underwent functional magnetic resonance imaging (fMRI) during a parametric ‘n-back’ task. The three groups were preselected to match on age, education and predicted IQ, and the two patient groups to have distinct insight levels. Performance and fMRI data were analysed to determine how groups of patients with preserved and poor insight differed from each other, and from healthy participants. Results Poor insight patients showed lower performance accuracy, relative to healthy participants (p = 0.01) and preserved insight patients (p = 0.08); the two patient groups were comparable on symptoms and medication. Preserved insight patients, relative to poor insight patients, showed greater activity most consistently in the precuneus and cerebellum (both bilateral) during WM; they also showed greater activity than healthy participants in the inferior–superior frontal gyrus and cerebellum (bilateral). Group differences in brain activity did not co-vary significantly with performance accuracy. Conclusions The precuneus and cerebellum function contribute to preserved insight in schizophrenia. Preserved insight as well as normal-range WM capacity in schizophrenia sub-groups may be achieved via compensatory neural activity in the frontal cortex and cerebellum. PMID:24332795

Development, validation and comparison of NIR and Raman methods for the identification and assay of poor-quality oral quinine drops.

PubMed

Mbinze, J K; Sacré, P-Y; Yemoa, A; Mavar Tayey Mbay, J; Habyalimana, V; Kalenda, N; Hubert, Ph; Marini, R D; Ziemons, E

2015-01-01

Poor quality antimalarial drugs are one of the public's major health problems in Africa. The depth of this problem may be explained in part by the lack of effective enforcement and the lack of efficient local drug analysis laboratories. To tackle part of this issue, two spectroscopic methods with the ability to detect and to quantify quinine dihydrochloride in children's oral drops formulations were developed and validated. Raman and near infrared (NIR) spectroscopy were selected for the drug analysis due to their low cost, non-destructive and rapid characteristics. Both of the methods developed were successfully validated using the total error approach in the range of 50-150% of the target concentration (20%W/V) within the 10% acceptance limits. Samples collected on the Congolese pharmaceutical market were analyzed by both techniques to detect potentially substandard drugs. After a comparison of the analytical performance of both methods, it has been decided to implement the method based on NIR spectroscopy to perform the routine analysis of quinine oral drop samples in the Quality Control Laboratory of Drugs at the University of Kinshasa (DRC). Copyright © 2015 Elsevier B.V. All rights reserved.

Relationship between time management in construction industry and project management performance

NASA Astrophysics Data System (ADS)

Nasir, Najuwa; Nawi, Mohd Nasrun Mohd; Radzuan, Kamaruddin

2016-08-01

Nowadays, construction industry particularly in Malaysia struggle in achieving status of eminent time management for construction project. Project managers have a great responsibility to keep the project success under time of project completion. However, studies shows that delays especially in Malaysian construction industry still unresolved due to weakness in managing the project. In addition, quality of time management on construction projects is generally poor. Due to the progressively extended delays issue, time performance becomes an important subject to be explored to investigate delay factors. The method of this study is review of literature towards issues in construction industry which affecting time performance of project in general by focusing towards process involved for project management. Based on study, it was found that knowledge, commitment, cooperation are the main criteria as an overall to manage the project into a smooth process during project execution until completion. It can be concluded that, the strength between project manager and team members in these main criteria while conducting the project towards good time performance is highly needed. However, there is lack of establishment towards factors of poor time performance which strongly related with project management. Hence, this study has been conducted to establish factors of poor time performance and its relations with project management.

Performances of some low-cost counter electrode materials in CdS and CdSe quantum dot-sensitized solar cells.

PubMed

Jun, Hieng Kiat; Careem, Mohamed Abdul; Arof, Abdul Kariem

2014-02-10

Different counter electrode (CE) materials based on carbon and Cu2S were prepared for the application in CdS and CdSe quantum dot-sensitized solar cells (QDSSCs). The CEs were prepared using low-cost and facile methods. Platinum was used as the reference CE material to compare the performances of the other materials. While carbon-based materials produced the best solar cell performance in CdS QDSSCs, platinum and Cu2S were superior in CdSe QDSSCs. Different CE materials have different performance in the two types of QDSSCs employed due to the different type of sensitizers and composition of polysulfide electrolytes used. The poor performance of QDSSCs with some CE materials is largely due to the lower photocurrent density and open-circuit voltage. The electrochemical impedance spectroscopy performed on the cells showed that the poor-performing QDSSCs had higher charge-transfer resistances and CPE values at their CE/electrolyte interfaces.

Alternative Methods for Estimating Achievement Trends and School Effects: When Is Simple Good Enough?

ERIC Educational Resources Information Center

Warkentien, Siri; Silver, David

2016-01-01

Public schools with impressive records of serving lower-performing students are often overlooked because their average test scores, even when students are growing quickly, are lower than scores in schools that serve higher-performing students. Schools may appear to be doing poorly either because baseline achievement is not easily accounted for or…

Examining Unusual Digit Span Performance in a Population of Postsecondary Students Assessed for Academic Difficulties

ERIC Educational Resources Information Center

Harrison, Allyson G.; Rosenblum, Yoni; Currie, Shannon

2010-01-01

Methods of identifying poor test-related motivation using the Wechsler Adult Intelligence Scale Digit Span subtest are based on identification of performance patterns that are implausible if the test taker is investing full effort. No studies to date, however, have examined the specificity of such measures, particularly when evaluating persons…

Academic Performance in ADHD when Controlled for Comorbid Learning Disorders, Family Income, and Parental Education in Brazil

ERIC Educational Resources Information Center

Carmine Pastura, Giuseppe Mario; Mattos, Paulo; Campos Araujo, Alexandra Prufer de Queiroz

2009-01-01

Objective: Scholastic achievement in a nonclinical sample of ADHD children and adolescents was evaluated taking into consideration variables such as comorbid learning disorders, family income, and parental education which may also be associated with poor academic performance. Method: After screening for ADHD in 396 students, the authors compared…

Risk prediction models of breast cancer: a systematic review of model performances.

PubMed

Anothaisintawee, Thunyarat; Teerawattananon, Yot; Wiratkapun, Chollathip; Kasamesup, Vijj; Thakkinstian, Ammarin

2012-05-01

The number of risk prediction models has been increasingly developed, for estimating about breast cancer in individual women. However, those model performances are questionable. We therefore have conducted a study with the aim to systematically review previous risk prediction models. The results from this review help to identify the most reliable model and indicate the strengths and weaknesses of each model for guiding future model development. We searched MEDLINE (PubMed) from 1949 and EMBASE (Ovid) from 1974 until October 2010. Observational studies which constructed models using regression methods were selected. Information about model development and performance were extracted. Twenty-five out of 453 studies were eligible. Of these, 18 developed prediction models and 7 validated existing prediction models. Up to 13 variables were included in the models and sample sizes for each study ranged from 550 to 2,404,636. Internal validation was performed in four models, while five models had external validation. Gail and Rosner and Colditz models were the significant models which were subsequently modified by other scholars. Calibration performance of most models was fair to good (expected/observe ratio: 0.87-1.12), but discriminatory accuracy was poor to fair both in internal validation (concordance statistics: 0.53-0.66) and in external validation (concordance statistics: 0.56-0.63). Most models yielded relatively poor discrimination in both internal and external validation. This poor discriminatory accuracy of existing models might be because of a lack of knowledge about risk factors, heterogeneous subtypes of breast cancer, and different distributions of risk factors across populations. In addition the concordance statistic itself is insensitive to measure the improvement of discrimination. Therefore, the new method such as net reclassification index should be considered to evaluate the improvement of the performance of a new develop model.

Sputum smear microscopy: evaluation of impact of training, microscope distribution, and use of external quality assessment guidelines for resource-poor settings.

PubMed

Van Rie, A; Fitzgerald, D; Kabuya, G; Van Deun, A; Tabala, M; Jarret, N; Behets, F; Bahati, E

2008-03-01

Sputum smear microscopy is the main and often only laboratory technique used for the diagnosis of tuberculosis in resource-poor countries, making quality assurance (QA) of smear microscopy an important activity. We evaluated the effects of a 5-day refresher training course for laboratory technicians and the distribution of new microscopes on the quality of smear microscopy in 13 primary health care laboratories in Kinshasa, Democratic Republic of Congo. The 2002 external QA guidelines for acid-fast bacillus smear microscopy were implemented, and blinded rechecking of the slides was performed before and 9 months after the training course and microscope distribution. We observed that the on-site checklist was highly time-consuming but could be tailored to capture frequent problems. Random blinded rechecking by the lot QA system method decreased the number of slides to be reviewed. Most laboratories needed further investigation for possible unacceptable performance, even according to the least-stringent interpretation. We conclude that the 2002 external QA guidelines are feasible for implementation in resource-poor settings, that the efficiency of external QA can be increased by selecting sample size parameters and interpretation criteria that take into account the local working conditions, and that greater attention should be paid to the provision of timely feedback and correction of the causes of substandard performance at poorly performing laboratories.

Children's school performance: impact of general and oral health.

PubMed

Blumenshine, Stephanie L; Vann, William F; Gizlice, Ziya; Lee, Jessica Y

2008-01-01

The purpose of this study was to examine: a) the sociodemographic and health factors associated with poor school performance among North Carolina children; and b) the impact of poor oral health status on school performance while controlling for other health and sociodemographic factors. We used data from the 2005 Child Health Assessment and Monitoring Program, a follow-back telephone survey to the Behavioral Risk Factor Surveillance System involving parents/guardians of children 0 to 17. This project includes sections on oral health and school performance. Our principal outcome variable was school performance and our major explanatory variable was children's oral health status, based upon parental report. Our sample consisted of 2,871 school children, weighted to reflect the North Carolina census. Bivariate analysis revealed that sex, race, parental education, low socioeconomic status, poor general health, poor oral health, and the interaction of poor oral health and general health were significantly related to school performance (P < 0.05). Logistic regression analysis demonstrates the effects of poor oral health and general health on school performance. Children with both poor oral health and general health were 2.3 times more likely to report poor school performance. Children with either poor oral health or general health were only 1.4 times more likely to report poor school performance. Our results show that children who have both poor oral health and general health are more likely to have poor school performance. Our findings suggest that the improvement of children's oral health may be a vehicle to improve their educational experience.

Classification accuracy of claims-based methods for identifying providers failing to meet performance targets.

PubMed

Hubbard, Rebecca A; Benjamin-Johnson, Rhondee; Onega, Tracy; Smith-Bindman, Rebecca; Zhu, Weiwei; Fenton, Joshua J

2015-01-15

Quality assessment is critical for healthcare reform, but data sources are lacking for measurement of many important healthcare outcomes. With over 49 million people covered by Medicare as of 2010, Medicare claims data offer a potentially valuable source that could be used in targeted health care quality improvement efforts. However, little is known about the operating characteristics of provider profiling methods using claims-based outcome measures that may estimate provider performance with error. Motivated by the example of screening mammography performance, we compared approaches to identifying providers failing to meet guideline targets using Medicare claims data. We used data from the Breast Cancer Surveillance Consortium and linked Medicare claims to compare claims-based and clinical estimates of cancer detection rate. We then demonstrated the performance of claim-based estimates across a broad range of operating characteristics using simulation studies. We found that identification of poor performing providers was extremely sensitive to algorithm specificity, with no approach identifying more than 65% of poor performing providers when claims-based measures had specificity of 0.995 or less. We conclude that claims have the potential to contribute important information on healthcare outcomes to quality improvement efforts. However, to achieve this potential, development of highly accurate claims-based outcome measures should remain a priority. Copyright © 2014 John Wiley & Sons, Ltd.

Evaluation of Tack Coat Bond Strength Tests

DOT National Transportation Integrated Search

2018-05-01

Poor bonding between asphalt pavement overlays and the substrate pavement layer can greatly influence the long term performance of hot mix asphalt (HMA) in the form of premature cracking and fatigue. The primary method to achieve bonding between laye...

[Genetic polymorphism in sparteine oxidation--occurrence in healthy volunteers in Slovakia].

PubMed

Holomán, J; Glasa, J; Veningerová, M; Prachar, V; Lukácsová, M

1997-02-01

The aim of this study was to estimate the occurrence of the phenotype of poor metabolizers of sparteine (in the frame of sparteine-debrisoquine-dextromethorphane polymorphism) in Slovakia. The authors examined a group of 216 of healthy volunteers (73 women and 143 men, average age of the group 24, 9 +/- 0.4 years), university students coming from various regions of Slovakia. The test substance-sparteine (1 x 100 mg tbl.) was administered perorally to all probands, in the evening after fasting. A 12-hour gathering of urine was subsequently performed. A sample of urine was subdued to examination. Isolation, separation, identification and assessment of the concentration of sparteine and its metabolites (2- and 5-dehydrosparteine) were performed by the method of gas chromatography. The metabolic MR ratio calculated from the ratio of the detected concentrations of sparteine and (2- and 5-dehydrosparteine) served for the assessment of the phenotype of poor (MR > 20), or rapid (MR < 20) metabolizers of sparteine in 8 authors found the poor metabolizer phenotype of 216 examined probands (i.e. in 3.75%). Its prevalence of the presented phenotype was lower than that anticipated on the basis of epidemiologic studies performed in other European countries. Study represents the first data on the phenotype of poor sparteine metabolizers in Slovakia. (Tab. 4, Fig. 1, Ref. 24.)

Correlation to FVIII:C in Two Thrombin Generation Tests: TGA-CAT and INNOVANCE ETP.

PubMed

Ljungkvist, Marcus; Berndtsson, Maria; Holmström, Margareta; Mikovic, Danijela; Elezovic, Ivo; Antovic, Jovan P; Zetterberg, Eva; Berntorp, Erik

2017-01-01

Several thrombin-generation tests are available, but few have been directly compared. Our primary aim was to investigate the correlation of two thrombin generation tests, thrombin generation assay-calibrated automated thrombogram (TGA-CAT) and INNOVANCE ETP, to factor VIII levels (FVIII:C) in a group of patients with hemophilia A. The secondary aim was to investigate inter-laboratory variation for the TGA-CAT method. Blood samples were taken from 45 patients with mild, moderate and severe hemophilia A. The TGA-CAT method was performed at both centers while the INNOVANCE ETP was only performed at the Stockholm center. Correlation between parameters was evaluated using Spearman's rank correlation test. For determination of the TGA-CAT inter-laboratory variability, Bland-Altman plots were used. The correlation for the INNOVANCE ETP and TGA-CAT methods with FVIII:C in persons with hemophilia (PWH) was r=0.701 and r=0.734 respectively.The correlation between the two methods was r=0.546.When dividing the study material into disease severity groups (mild, moderate and severe) based on FVIII levels, both methods fail to discriminate between them.The variability of the TGA-CAT results performed at the two centers was reduced after normalization; before normalization, 29% of values showed less than ±10% difference while after normalization the number increased to 41%. Both methods correlate in an equal manner to FVIII:C in PWH but show a poor correlation with each other. The level of agreement for the TGA-CAT method was poor though slightly improved after normalization of data. Further improvement of standardization of these methods is warranted.

The Stock Performance of C. Everett Koop Award Winners Compared With the Standard & Poor's 500 Index

PubMed Central

Goetzel, Ron Z.; Fabius, Raymond; Fabius, Dan; Roemer, Enid C.; Thornton, Nicole; Kelly, Rebecca K.; Pelletier, Kenneth R.

2016-01-01

Objective: To explore the link between companies investing in the health and well-being programs of their employees and stock market performance. Methods: Stock performance of C. Everett Koop National Health Award winners (n = 26) was measured over time and compared with the average performance of companies comprising the Standard and Poor's (S&P) 500 Index. Results: The Koop Award portfolio outperformed the S&P 500 Index. In the 14-year period tracked (2000–2014), Koop Award winners’ stock values appreciated by 325% compared with the market average appreciation of 105%. Conclusions: This study supports prior and ongoing research demonstrating a higher market valuation—an affirmation of business success by Wall Street investors—of socially responsible companies that invest in the health and well-being of their workers when compared with other publicly traded firms. PMID:26716843

Timing of operation for poor-grade aneurysmal subarachnoid hemorrhage: study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background Subarachnoid hemorrhage is a common and dangerous disease with an unfavorable prognosis. Patients with poor-grade subarachnoid hemorrhage (Hunt & Hess Grades 4–5) are unconscious on admission. Because of the high mortality and disability rate associated with poor-grade subarachnoid hemorrhage, it is often treated conservatively. Timing of surgery for poor-grade aneurysmal subarachnoid hemorrhage is still controversial, therefore this study aims to identify the optimal time to operate on patients admitted in poor clinical condition. Methods/design Ninety-nine patients meeting the inclusion criteria were randomly assigned into three treatment groups. The early surgery group received operation within 3 days after onset of subarachnoid hemorrhage (day of SAH = day 1); the intermediate surgery group received operation from days 4 to 7, and surgery was performed on the late surgery group after day 7. Follow-up was performed 1, 3, and 6 months after aneurysm clipping. Primary indicators of outcome included the Extended Glasgow Outcome Scale and the Modified Rankin Scale, while secondary indicators of outcome were assessed using the Barthel Index and mortality. Discussion This is the first prospective, single-center, observer-blinded, randomized controlled trial to elucidate optimal timing for surgery in poor-grade subarachnoid hemorrhage patients. The results of this study will be used to direct decisions of surgical intervention in poor-grade subarachnoid hemorrhage, thus improving clinical outcomes for patients. Trial registration Chinese Clinical Trial Registry: ChiCTR-TRC-12002917 PMID:23957458

Health facility and skilled birth deliveries among poor women with Jamkesmas health insurance in Indonesia: a mixed-methods study.

PubMed

Brooks, Mohamad I; Thabrany, Hasbullah; Fox, Matthew P; Wirtz, Veronika J; Feeley, Frank G; Sabin, Lora L

2017-02-02

The growing momentum for quality and affordable health care for all has given rise to the recent global universal health coverage (UHC) movement. As part of Indonesia's strategy to achieve the goal of UHC, large investments have been made to increase health access for the poor, resulting in the implementation of various health insurance schemes targeted towards the poor and near-poor, including the Jamkesmas program. In the backdrop of Indonesia's aspiration to reach UHC is the high rate of maternal mortality that disproportionally affects poor women. The objective of this study was to evaluate the association of health facility and skilled birth deliveries among poor women with and without Jamkesmas and explore perceived barriers to health insurance membership and maternal health service utilization. We used a mixed-methods design. Utilizing data from the 2012 Indonesian Demographic and Health Survey (n = 45,607), secondary analysis using propensity score matching was performed on key outcomes of interest: health facility delivery (HFD) and skilled birth delivery (SBD). In-depth interviews (n = 51) were conducted in the provinces of Jakarta and Banten among poor women, midwives, and government representatives. Thematic framework analysis was performed on qualitative data to explore perceived barriers. In 2012, 63.0% of women did not have health insurance; 19.1% had Jamkesmas. Poor women with Jamkesmas were 19% (OR = 1.19 [1.03-1.37]) more likely to have HFD and 17% (OR = 1.17 [1.01-1.35]) more likely to have SBD compared to poor women without insurance. Qualitative interviews highlighted key issues, including: lack of proper documentation for health insurance registration; the preference of pregnant women to deliver in their parents' village; the use of traditional birth attendants; distance to health facilities; shortage of qualified health providers; overcrowded health facilities; and lack of health facility accreditation. Poor women with Jamkesmas membership had a modest increase in HFD and SBD. These findings are consistent with economic theory that health insurance coverage can reduce financial barriers to care and increase service uptake. However, factors such as socio-cultural beliefs, accessibility, and quality of care are important elements that need to be addressed as part of the national UHC agenda to improve maternal health services in Indonesia.

5 CFR 9701.408 - Developing performance and addressing poor performance.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Developing performance and addressing poor performance. (a) Subject to budgetary and other organizational... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Developing performance and addressing poor performance. 9701.408 Section 9701.408 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY...

Early Detection of At-Risk Undergraduate Students through Academic Performance Predictors

ERIC Educational Resources Information Center

Rowtho, Vikash

2017-01-01

Undergraduate student dropout is gradually becoming a global problem and the 39 Small Islands Developing States (SIDS) are no exception to this trend. The purpose of this research was to develop a method that can be used for early detection of students who are at-risk of performing poorly in their undergraduate studies. A sample of 279 students…

Software reliability perspectives

NASA Technical Reports Server (NTRS)

Wilson, Larry; Shen, Wenhui

1987-01-01

Software which is used in life critical functions must be known to be highly reliable before installation. This requires a strong testing program to estimate the reliability, since neither formal methods, software engineering nor fault tolerant methods can guarantee perfection. Prior to the final testing software goes through a debugging period and many models have been developed to try to estimate reliability from the debugging data. However, the existing models are poorly validated and often give poor performance. This paper emphasizes the fact that part of their failures can be attributed to the random nature of the debugging data given to these models as input, and it poses the problem of correcting this defect as an area of future research.

The relationship of written examination performance to safe driving : a literature review with recommended methods for developing exams.

DOT National Transportation Integrated Search

1984-01-01

This report reviews the literature concerning written driver license examinations. The research literature shows that current written examinations are poor predictors of unsafe drivers. Although some studies demonstrate significant relationships betw...

A STUDY OF LONGITUDINAL PATTERNS OF FAILURE AMONG HIGH SCHOOL DROP-OUTS AND POORLY PERFORMING GRADUATES.

ERIC Educational Resources Information Center

STOLLER, DAVID S.

THE RELATIONSHIP BETWEEN PATTERNS OF POOR PERFORMANCE AND SIGNIFICANT DISTINGUISHING FACTORS WHICH MIGHT IDENTIFY DROPOUTS IS EXPLORED. DATA WERE OBTAINED ON 270 STUDENTS (FROM A PARENT POPULATION OF 2,500) WHO WERE POOR PERFORMERS (POOR PERFORMANCE BEING DEFINED AS THREE "D'S" OR "F'S" IN HIGH SCHOOL). THE VAST MAJORITY OF…

Testing mapping algorithms of the cancer-specific EORTC QLQ-C30 onto EQ-5D in malignant mesothelioma.

PubMed

Arnold, David T; Rowen, Donna; Versteegh, Matthijs M; Morley, Anna; Hooper, Clare E; Maskell, Nicholas A

2015-01-23

In order to estimate utilities for cancer studies where the EQ-5D was not used, the EORTC QLQ-C30 can be used to estimate EQ-5D using existing mapping algorithms. Several mapping algorithms exist for this transformation, however, algorithms tend to lose accuracy in patients in poor health states. The aim of this study was to test all existing mapping algorithms of QLQ-C30 onto EQ-5D, in a dataset of patients with malignant pleural mesothelioma, an invariably fatal malignancy where no previous mapping estimation has been published. Health related quality of life (HRQoL) data where both the EQ-5D and QLQ-C30 were used simultaneously was obtained from the UK-based prospective observational SWAMP (South West Area Mesothelioma and Pemetrexed) trial. In the original trial 73 patients with pleural mesothelioma were offered palliative chemotherapy and their HRQoL was assessed across five time points. This data was used to test the nine available mapping algorithms found in the literature, comparing predicted against observed EQ-5D values. The ability of algorithms to predict the mean, minimise error and detect clinically significant differences was assessed. The dataset had a total of 250 observations across 5 timepoints. The linear regression mapping algorithms tested generally performed poorly, over-estimating the predicted compared to observed EQ-5D values, especially when observed EQ-5D was below 0.5. The best performing algorithm used a response mapping method and predicted the mean EQ-5D with accuracy with an average root mean squared error of 0.17 (Standard Deviation; 0.22). This algorithm reliably discriminated between clinically distinct subgroups seen in the primary dataset. This study tested mapping algorithms in a population with poor health states, where they have been previously shown to perform poorly. Further research into EQ-5D estimation should be directed at response mapping methods given its superior performance in this study.

Integration of membrane distillation into traditional salt farming method: Process development and modelling

NASA Astrophysics Data System (ADS)

Hizam, S.; Bilad, M. R.; Putra, Z. A.

2017-10-01

Farmers still practice the traditional salt farming in many regions, particularly in Indonesia. This archaic method not only produces low yield and poor salt quality, it is also laborious. Furthermore, the farming locations typically have poor access to fresh water and are far away from electricity grid, which restrict upgrade to a more advanced technology for salt production. This paper proposes a new concept of salt harvesting method that improves the salt yield and at the same time facilitates recovery of fresh water from seawater. The new concept integrates solar powered membrane distillation (MD) and photovoltaic cells to drive the pumping. We performed basic solar still experiments to quantify the heat flux received by a pond. The data were used as insight for designing the proposed concept, particularly on operational strategy and the most effective way to integrate MD. After the conceptual design had been developed, we formulated mass and energy balance to estimate the performance of the proposed concept. Based on our data and design, it is expected that the system would improve the yield and quality of the salt production, maximizing fresh water harvesting, and eventually provides economical gain for salt farmers hence improving their quality of life. The key performance can only be measured via experiment using gain output ratio as performance indicator, which will be done in a future study.

Choosing a design to fit the situation: how to improve specificity and positive predictive values using Bayesian lot quality assurance sampling

PubMed Central

Olives, Casey; Pagano, Marcello

2013-01-01

Background Lot Quality Assurance Sampling (LQAS) is a provably useful tool for monitoring health programmes. Although LQAS ensures acceptable Producer and Consumer risks, the literature alleges that the method suffers from poor specificity and positive predictive values (PPVs). We suggest that poor LQAS performance is due, in part, to variation in the true underlying distribution. However, until now the role of the underlying distribution in expected performance has not been adequately examined. Methods We present Bayesian-LQAS (B-LQAS), an approach to incorporating prior information into the choice of the LQAS sample size and decision rule, and explore its properties through a numerical study. Additionally, we analyse vaccination coverage data from UNICEF’s State of the World’s Children in 1968–1989 and 2008 to exemplify the performance of LQAS and B-LQAS. Results Results of our numerical study show that the choice of LQAS sample size and decision rule is sensitive to the distribution of prior information, as well as to individual beliefs about the importance of correct classification. Application of the B-LQAS approach to the UNICEF data improves specificity and PPV in both time periods (1968–1989 and 2008) with minimal reductions in sensitivity and negative predictive value. Conclusions LQAS is shown to be a robust tool that is not necessarily prone to poor specificity and PPV as previously alleged. In situations where prior or historical data are available, B-LQAS can lead to improvements in expected performance. PMID:23378151

The Subjective Well-Being Method of Valuation: An Application to General Health Status.

PubMed

Brown, Timothy T

2015-12-01

To introduce the subjective well-being (SWB) method of valuation and provide an example by valuing health status. The SWB method allows monetary valuations to be performed in the absence of market relationships. Data are from the 1975-2010 General Social Survey. The value of health status is determined via the estimation of an implicit derivative based on a happiness equation. Two-stage least-squares was used to estimate happiness as a function of poor-to-fair health status, annual household income adjusted for household size, age, sex, race, marital status, education, year, and season. Poor-to-fair health status and annual household income are instrumented using a proxy for intelligence, a temporal version of the classic distance instrument, and the average health status of individuals who are demographically similar but geographically separated. Instrument validity is evaluated. Moving from good/excellent health to poor/fair health (1 year of lower health status) is equivalent to the loss of $41,654 of equivalized household income (2010 constant dollars) per annum, which is larger than median equivalized household income. The SWB method may be useful in making monetary valuations where fundamental market relationships are not present. © Health Research and Educational Trust.

Poor oral health including active caries in 187 UK professional male football players: clinical dental examination performed by dentists.

PubMed

Needleman, Ian; Ashley, Paul; Meehan, Lyndon; Petrie, Aviva; Weiler, Richard; McNally, Steve; Ayer, Chris; Hanna, Rob; Hunt, Ian; Kell, Steven; Ridgewell, Paul; Taylor, Russell

2016-01-01

The few studies that have assessed oral health in professional/elite football suggest poor oral health with minimal data on impact on performance. The aim of this research was to determine oral health in a representative sample of professional footballers in the UK and investigate possible determinants of oral health and self-reported impact on well-being, training and performance. Clinical oral health examination of senior squad players using standard methods and outcomes carried out at club training facilities. Questionnaire data were also collected. 8 teams were included, 5 Premier League, 2 Championship and 1 League One. 6 dentists examined 187 players who represented >90% of each senior squad. Oral health was poor: 37% players had active dental caries, 53% dental erosion and 5% moderate-severe irreversible periodontal disease. 45% were bothered by their oral health, 20% reported an impact on their quality of life and 7% on training or performance. Despite attendance for dental check-ups, oral health deteriorated with age. This is the first large, representative sample study in professional football. Oral health of professional footballers is poor, and this impacts on well-being and performance. Successful strategies to promote oral health within professional football are urgently needed, and research should investigate models based on best evidence for behaviour change and implementation science. Furthermore, this study provides strong evidence to support oral health screening within professional football. 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/

Small area estimation (SAE) model: Case study of poverty in West Java Province

NASA Astrophysics Data System (ADS)

Suhartini, Titin; Sadik, Kusman; Indahwati

2016-02-01

This paper showed the comparative of direct estimation and indirect/Small Area Estimation (SAE) model. Model selection included resolve multicollinearity problem in auxiliary variable, such as choosing only variable non-multicollinearity and implemented principal component (PC). Concern parameters in this paper were the proportion of agricultural venture poor households and agricultural poor households area level in West Java Province. The approach for estimating these parameters could be performed based on direct estimation and SAE. The problem of direct estimation, three area even zero and could not be conducted by directly estimation, because small sample size. The proportion of agricultural venture poor households showed 19.22% and agricultural poor households showed 46.79%. The best model from agricultural venture poor households by choosing only variable non-multicollinearity and the best model from agricultural poor households by implemented PC. The best estimator showed SAE better then direct estimation both of the proportion of agricultural venture poor households and agricultural poor households area level in West Java Province. The solution overcame small sample size and obtained estimation for small area was implemented small area estimation method for evidence higher accuracy and better precision improved direct estimator.

Materials and fabrication of electrode scaffolds for deposition of MnO2 and their true performance in supercapacitors

NASA Astrophysics Data System (ADS)

Cao, Jianyun; Li, Xiaohong; Wang, Yaming; Walsh, Frank C.; Ouyang, Jia-Hu; Jia, Dechang; Zhou, Yu

2015-10-01

MnO2 is a promising electrode material for high energy supercapacitors because of its large pseudo-capacitance. However, MnO2 suffers from low electronic conductivity and poor cation diffusivity, which results in poor utilization and limited rate performance of traditional MnO2 powder electrodes, obtained by pressing a mixed paste of MnO2 powder, conductive additive and polymer binder onto metallic current collectors. Developing binder-free MnO2 electrodes by loading nanoscale MnO2 deposits on pre-fabricated device-ready electrode scaffolds is an effective way to achieve both high power and energy performance. These electrode scaffolds, with interconnected skeletons and pore structures, will not only provide mechanical support and electron collection as traditional current collectors but also fast ion transfer tunnels, leading to high MnO2 utilization and rate performance. This review covers design strategies, materials and fabrication methods for the electrode scaffolds. Rational evaluation of the true performance of these electrodes is carried out, which clarifies that some of the electrodes with as-claimed exceptional performances lack potential in practical applications due to poor mass loading of MnO2 and large dead volume of inert scaffold materials/void spaces in the electrode structure. Possible ways to meet this challenge and bring MnO2 electrodes from laboratory studies to real-world applications are considered.

Combining Correlation Matrices: Simulation Analysis of Improved Fixed-Effects Methods

ERIC Educational Resources Information Center

Hafdahl, Adam R.

2007-01-01

The originally proposed multivariate meta-analysis approach for correlation matrices--analyze Pearson correlations, with each study's observed correlations replacing their population counterparts in its conditional-covariance matrix--performs poorly. Two refinements are considered: Analyze Fisher Z-transformed correlations, and substitute better…

Presentation and outcome of clinical poor performance in one health district over a 5-year period: 2002–2007

PubMed Central

Cox, Stephen J; Holden, John D

2009-01-01

Background The detection, assessment, and management of primary care poor performance raise difficult issues for all those involved. Guidance has largely focused on managing the most serious cases where patient safety is severely compromised. The management of primary care poor performance has become an increasingly important part of primary care trust (PCT) work, but its modes of presentation and prevalence are not well known. Aim To report the prevalence, presentation modes, and management of primary care poor performance cases presenting to one PCT over a 5-year period. Design of study A retrospective review of primary care poor performance cases in one district. Setting St Helens PCT administered 35 practices with 130 GPs on the performers list, caring for 190 110 patients in North West England, UK. Method Cases presenting during 2002–2007 were initially reviewed by the chair of the PCT clinical executive committee. Anonymised data were then jointly reviewed by the assessor and another experienced GP advisor. Results There were 102 individual presentations (20 per year or one every 2–3 weeks) where clinician performance raised significant cause for concern occurred over the 5-year period. These concerns related to 37 individual clinicians, a range of 1–14 per clinician (mean 2.7). Whistleblowing by professional colleagues on 43 occasions was the most common presentation, of which 26 were from GPs about GPs. Patient complaints (18) were the second most common presentation. Twenty-seven clinicians were GPs, of whom the General Medical Council (GMC) were notified or involved in 13 cases. Clinicians were supported locally, and remedying was exclusively locally managed in 14 cases, and shared with an external organisation (such as the GMC or deanery) in another 12. Conclusion Professional whistleblowing and patient complaints were the most common sources of presentation. Effective PCT teams are needed to manage clinicians whose performance gives cause for concern. Sufficient resources and both formal and informal ways of reporting concerns are essential. PMID:19401017

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.

An Investigation to Improve Quality Evaluations of Primers and Propellant for 20mm Munitions

NASA Technical Reports Server (NTRS)

Bement, L. J.; Holmes, C.; McGrory, J.; Schimmel, M. L.

1997-01-01

To reduce the frequency of electrically initiated, 20mm munition hangfires (delayed ignitions), a joint Army/NASA investigation was conducted to recommend quality evaluation improvements for acceptance of both primers and gun propellant. This effort focused only on evaluating ignition and combustion performance as potential causes of hangfires: poor electrical initiation of the primer, low output performance of the primer, low ignition sensitivity of the gun propellant, and the effects of cold temperature. The goal was to determine the "best" of the Army and NASA test methods to assess the functional performance of primers and gun propellants. The approach was to evaluate the performance of both high-quality and deliberately defective primers to challenge the sensitivity of test methods. In addition, the ignition sensitivity of different manufacturing batches of gun propellants was evaluated. The results of the investigation revealed that improvements can be made in functional evaluations that can assist in identifying and reducing ignition and performance variations. The "best" functional evaluation of primers and propellant is achieved through a combination of both Army and NASA test methods. Incorporating the recommendations offered in this report may provide for considerable savings in reducing the number of cartridge firings, while significantly lowering the rejection rate of primer, propellant and cartridge lots. The most probable causes for ignition and combustion-related hangfires were the lack of calcium silicide in the primer mix, a low output performance of primers, and finally, poor ignition sensitivity of gun propellant. Cold temperatures further reduce propellant ignition sensitivity, as well as reducing burn rate and chamber pressures.

Complications from laser-assisted liposuction performed by noncore practitioners.

PubMed

Blum, Craig A; Sasser, Charles G S; Kaplan, Jonathan L

2013-10-01

Liposuction is one of the most commonly performed aesthetic surgery procedures in the United States, and most plastic surgeons perform suction-assisted, ultrasound-assisted, or power-assisted liposuction. The past decade has seen a growing interest in laser-assisted liposuction (LAL) and the proposed advantages of traditional liposuction methods. However, it is performed by a minority of plastic surgeons. In fact, many LAL providers are not trained in aesthetic practice, and many offer LAL as their only body-contouring procedure. When only one method of body contouring is available to a provider, it may lead to inappropriate patient selection with associated poor outcomes. This report discusses the use of laser liposuction in body contouring and the demographics of those performing liposuction, including LAL. Complications from laser-assisted liposuction performed by noncore practitioners are illustrated.

Intensity Variation Normalization for Finger Vein Recognition Using Guided Filter Based Singe Scale Retinex

PubMed Central

Xie, Shan Juan; Lu, Yu; Yoon, Sook; Yang, Jucheng; Park, Dong Sun

2015-01-01

Finger vein recognition has been considered one of the most promising biometrics for personal authentication. However, the capacities and percentages of finger tissues (e.g., bone, muscle, ligament, water, fat, etc.) vary person by person. This usually causes poor quality of finger vein images, therefore degrading the performance of finger vein recognition systems (FVRSs). In this paper, the intrinsic factors of finger tissue causing poor quality of finger vein images are analyzed, and an intensity variation (IV) normalization method using guided filter based single scale retinex (GFSSR) is proposed for finger vein image enhancement. The experimental results on two public datasets demonstrate the effectiveness of the proposed method in enhancing the image quality and finger vein recognition accuracy. PMID:26184226

Intensity Variation Normalization for Finger Vein Recognition Using Guided Filter Based Singe Scale Retinex.

PubMed

Xie, Shan Juan; Lu, Yu; Yoon, Sook; Yang, Jucheng; Park, Dong Sun

2015-07-14

Finger vein recognition has been considered one of the most promising biometrics for personal authentication. However, the capacities and percentages of finger tissues (e.g., bone, muscle, ligament, water, fat, etc.) vary person by person. This usually causes poor quality of finger vein images, therefore degrading the performance of finger vein recognition systems (FVRSs). In this paper, the intrinsic factors of finger tissue causing poor quality of finger vein images are analyzed, and an intensity variation (IV) normalization method using guided filter based single scale retinex (GFSSR) is proposed for finger vein image enhancement. The experimental results on two public datasets demonstrate the effectiveness of the proposed method in enhancing the image quality and finger vein recognition accuracy.

Neuromuscular Evaluation With Single-Leg Squat Test at 6 Months After Anterior Cruciate Ligament Reconstruction

PubMed Central

Hall, Michael P.; Paik, Ronald S.; Ware, Anthony J.; Mohr, Karen J.; Limpisvasti, Orr

2015-01-01

Background: Criteria for return to unrestricted activity after anterior cruciate ligament (ACL) reconstruction varies, with some using time after surgery as the sole criterion—most often at 6 months. Patients may have residual neuromuscular deficits, which may increase the risk of ACL injury. A single-leg squat test (SLST) can dynamically assess for many of these deficits prior to return to unrestricted activity. Hypothesis: A significant number of patients will continue to exhibit neuromuscular deficits with SLST at 6 months after ACL reconstruction. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Patients using a standardized accelerated rehabilitation protocol at their 6-month follow-up after primary ACL reconstruction were enrolled. Evaluation included bilateral SLST, single-leg hop distance, hip abduction strength, and the subjective International Knee Documentation Committee (IKDC) score. Results: Thirty-three patients were enrolled. Poor performance of the operative leg SLST was found in 15 of 33 patients (45%). Of those 15 patients, 7 (45%) had concomitant poor performance of the nonoperative leg compared with 2 of 18 patients (11%) in those who demonstrated good performance in the operative leg. The poor performers were significantly older (33.6 years) than the good performers (24.2 years) (P = .007). Those with poor performance demonstrated decreased hip abduction strength (17.6 kg operative leg vs 20.5 kg nonoperative leg) (P = .024), decreased single-leg hop distance (83.3 cm operative leg vs 112.3 cm nonoperative leg) (P = .036), and lower IKDC scores (67.9 vs 82.3) (P = .001). Conclusion: Nearly half of patients demonstrated persistent neuromuscular deficits on SLST at 6 months, which is when many patients return to unrestricted activity. Those with poor performance were of a significantly older age, decreased hip abduction strength, decreased single-leg hop distance, and lower IKDC subjective scores. Clinical Relevance: The SLST can be used to identify neuromuscular risk factors for ACL rupture. Many patients at 6 months have persistent neuromuscular deficits on SLST. Caution should be used when using time alone to determine when patients can return to unrestricted activity. PMID:26665033

Color Retinal Image Enhancement Based on Luminosity and Contrast Adjustment.

PubMed

Zhou, Mei; Jin, Kai; Wang, Shaoze; Ye, Juan; Qian, Dahong

2018-03-01

Many common eye diseases and cardiovascular diseases can be diagnosed through retinal imaging. However, due to uneven illumination, image blurring, and low contrast, retinal images with poor quality are not useful for diagnosis, especially in automated image analyzing systems. Here, we propose a new image enhancement method to improve color retinal image luminosity and contrast. A luminance gain matrix, which is obtained by gamma correction of the value channel in the HSV (hue, saturation, and value) color space, is used to enhance the R, G, and B (red, green and blue) channels, respectively. Contrast is then enhanced in the luminosity channel of L * a * b * color space by CLAHE (contrast-limited adaptive histogram equalization). Image enhancement by the proposed method is compared to other methods by evaluating quality scores of the enhanced images. The performance of the method is mainly validated on a dataset of 961 poor-quality retinal images. Quality assessment (range 0-1) of image enhancement of this poor dataset indicated that our method improved color retinal image quality from an average of 0.0404 (standard deviation 0.0291) up to an average of 0.4565 (standard deviation 0.1000). The proposed method is shown to achieve superior image enhancement compared to contrast enhancement in other color spaces or by other related methods, while simultaneously preserving image naturalness. This method of color retinal image enhancement may be employed to assist ophthalmologists in more efficient screening of retinal diseases and in development of improved automated image analysis for clinical diagnosis.

Application of maximum likelihood methods to laser Thomson scattering measurements of low density plasmas

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

Washeleski, Robert L.; Meyer, Edmond J. IV; King, Lyon B.

2013-10-15

Laser Thomson scattering (LTS) is an established plasma diagnostic technique that has seen recent application to low density plasmas. It is difficult to perform LTS measurements when the scattered signal is weak as a result of low electron number density, poor optical access to the plasma, or both. Photon counting methods are often implemented in order to perform measurements in these low signal conditions. However, photon counting measurements performed with photo-multiplier tubes are time consuming and multi-photon arrivals are incorrectly recorded. In order to overcome these shortcomings a new data analysis method based on maximum likelihood estimation was developed. Themore » key feature of this new data processing method is the inclusion of non-arrival events in determining the scattered Thomson signal. Maximum likelihood estimation and its application to Thomson scattering at low signal levels is presented and application of the new processing method to LTS measurements performed in the plume of a 2-kW Hall-effect thruster is discussed.« less

Application of maximum likelihood methods to laser Thomson scattering measurements of low density plasmas.

PubMed

Washeleski, Robert L; Meyer, Edmond J; King, Lyon B

2013-10-01

Laser Thomson scattering (LTS) is an established plasma diagnostic technique that has seen recent application to low density plasmas. It is difficult to perform LTS measurements when the scattered signal is weak as a result of low electron number density, poor optical access to the plasma, or both. Photon counting methods are often implemented in order to perform measurements in these low signal conditions. However, photon counting measurements performed with photo-multiplier tubes are time consuming and multi-photon arrivals are incorrectly recorded. In order to overcome these shortcomings a new data analysis method based on maximum likelihood estimation was developed. The key feature of this new data processing method is the inclusion of non-arrival events in determining the scattered Thomson signal. Maximum likelihood estimation and its application to Thomson scattering at low signal levels is presented and application of the new processing method to LTS measurements performed in the plume of a 2-kW Hall-effect thruster is discussed.

Nanostructure-based proton exchange membrane for fuel cell applications at high temperature.

PubMed

Li, Junsheng; Wang, Zhengbang; Li, Junrui; Pan, Mu; Tang, Haolin

2014-02-01

As a clean and highly efficient energy source, the proton exchange membrane fuel cell (PEMFC) has been considered an ideal alternative to traditional fossil energy sources. Great efforts have been devoted to realizing the commercialization of the PEMFC in the past decade. To eliminate some technical problems that are associated with the low-temperature operation (such as catalyst poisoning and poor water management), PEMFCs are usually operated at elevated temperatures (e.g., > 100 degrees C). However, traditional proton exchange membrane (PEM) shows poor performance at elevated temperature. To achieve a high-performance PEM for high temperature fuel cell applications, novel PEMs, which are based on nanostructures, have been developed recently. In this review, we discuss and summarize the methods for fabricating the nanostructure-based PEMs for PEMFC operated at elevated temperatures and the high temperature performance of these PEMs. We also give an outlook on the rational design and development of the nanostructure-based PEMs.

Surface pavement solutions for poor subgrade conditions phase II : performance analysis of test sections and implementation guidelines : summary.

DOT National Transportation Integrated Search

2010-12-01

Several areas within FDOT Districts 4 and 6 contain thick layers of organic soils at relatively shallow depths. Roads built on these soft compressible soils : often develop premature cracking, distortion, and settlement. Traditional repair methods, s...

[Excessive Daytime Sleepiness, Poor Quality Sleep, and Low Academic Performance in Medical Students].

PubMed

Machado-Duque, Manuel Enrique; Echeverri Chabur, Jorge Enrique; Machado-Alba, Jorge Enrique

2015-01-01

Quality of sleep and excessive daytime sleepiness (EDS) affect cognitive ability and performance of medical students. This study attempts to determine the prevalence of EDS, sleep quality, and assess their association with poor academic performance in this population. A descriptive, observational study was conducted on a random sample of 217 medical students from the Universidad Tecnológica de Pereira, who completed the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the Epworth sleepiness scale. Sociodemographic, clinic and academic variables were also measured. Multivariate analyses for poor academic performance were performed. The included students had a mean age of 21.7±3.3 years, of whom 59.4% were men. Almost half (49.8%) had EDS criteria, and 79.3% were poor sleepers (PSQI ≥ 5), while 43.3% had poor academic performance during the last semester. The bivariate analysis showed that having used tobacco or alcohol until intoxicated, fairly bad subjective sleep quality, sleep efficiency < 65%, and being a poor sleeper were associated with increased risk of low performance. Sleep efficiency < 65% was statistically associated with poor academic performance (P=.024; OR = 4.23; 95% CI, 1.12-15.42) in the multivariate analysis. A poor sleep quality determined by low efficiency was related to poor academic achievement at the end of semester in medical students. Copyright © 2015 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Tuberculin reactivity in bacille Calmette-Guérin vaccinated populations: a compilation of international data.

PubMed

Joos, T J; Miller, W C; Murdoch, D M

2006-08-01

The effect of previously administered bacille Calmette-Guérin (BCG) vaccine on subsequent tuberculin skin tests (TSTs) complicates screening for latent tuberculosis infection (LTBI) in foreign-born persons. To determine the usefulness of the TST as a screening test for LTBI in foreign-born persons. A literature search was performed of published studies that compared tuberculin reactivity amongst BCG-vaccinated and non-vaccinated groups. The percentages of positive reactors in the two groups were then used to calculate a prevalence ratio. The prevalence ratio varied with the age of the groups tested and the incidence of TB in their countries of origin. The TST performed poorly in vaccinated persons of all ages from countries of low TB incidence, but was a useful screen for LTBI in vaccinated adults from countries of high and intermediate incidence. The test performed poorly as a screening method for vaccinated children under 2 years of age. Its usefulness in vaccinated children aged 2-14 years varied considerably. The usefulness of the TST as a screening method for LTBI depends on the age of the patient and the incidence of TB in their country of origin.

Studies on Hot-Melt Prepregging on PRM-II-50 Polyimide Resin with Graphite Fibers

NASA Technical Reports Server (NTRS)

Shin, E. Eugene; Sutter, James K.; Juhas, John; Veverka, Adrienne; Klans, Ojars; Inghram, Linda; Scheiman, Dan; Papadopoulos, Demetrios; Zoha, John; Bubnick, Jim

2004-01-01

A second generation PMR (in situ Polymerization of Monomer Reactants) polyimide resin PMR-II-50, has been considered for high temperature and high stiffness space propulsion composites applications for its improved high temperature performance. As part of composite processing optimization, two commercial prepregging methods: solution vs. hot-melt processes were investigated with M40J fabrics from Toray. In a previous study a systematic chemical, physical, thermal and mechanical characterization of these composites indicated the poor resin-fiber interfacial wetting, especially for the hot-melt process, resulted in poor composite quality. In order to improve the interfacial wetting, optimization of the resin viscosity and process variables were attempted in a commercial hot-melt prepregging line. In addition to presenting the results from the prepreg quality optimization trials, the combined effects of the prepregging method and two different composite cure methods, i.e. hot press vs. autoclave on composite quality and properties are discussed.

Studies on Hot-Melt Prepregging of PMR-II-50 Polyimide Resin with Graphite Fibers

NASA Technical Reports Server (NTRS)

Shin, E. Eugene; Sutter, James K.; Juhas, John; Veverka, Adrienne; Klans, Ojars; Inghram, Linda; Scheiman, Dan; Papadopoulos, Demetrios; Zoha, John; Bubnick, Jim

2003-01-01

A Second generation PMR (in situ Polymerization of Monomer Reactants) polyimide resin, PMR-II-50, has been considered for high temperature and high stiffness space propulsion composites applications for its improved high temperature performance. As part of composite processing optimization, two commercial prepregging methods: solution vs. hot-melt processes were investigated with M40J fabrics from Toray. In a previous study a systematic chemical, physical, thermal and mechanical characterization of these composites indicated that poor resin-fiber interfacial wetting, especially for the hot-melt process, resulted in poor composite quality. In order to improve the interfacial wetting, optimization of the resin viscosity and process variables were attempted in a commercial hot-melt prepregging line. In addition to presenting the results from the prepreg quality optimization trials, the combined effects of the prepregging method and two different composite cure methods, i.e., hot press vs. autoclave on composite quality and properties are discussed.

Forgotten forests--issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study.

PubMed

Särkinen, Tiina; Iganci, João R V; Linares-Palomino, Reynaldo; Simon, Marcelo F; Prado, Darién E

2011-11-24

South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species. Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data. Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be particularly useful for mapping poorly known, fragmented, or degraded vegetation. We wish to highlight that biome delimitation is not an exact science, and that transparency is needed on how biomes are used as study units in macroevolutionary and ecological research.

Forgotten forests - issues and prospects in biome mapping using Seasonally Dry Tropical Forests as a case study

PubMed Central

2011-01-01

Background South America is one of the most species diverse continents in the world. Within South America diversity is not distributed evenly at both local and continental scales and this has led to the recognition of various areas with unique species assemblages. Several schemes currently exist which divide the continental-level diversity into large species assemblages referred to as biomes. Here we review five currently available biome maps for South America, including the WWF Ecoregions, the Americas basemap, the Land Cover Map of South America, Morrone's Biogeographic regions of Latin America, and the Ecological Systems Map. The comparison is performed through a case study on the Seasonally Dry Tropical Forest (SDTF) biome using herbarium data of habitat specialist species. Results Current biome maps of South America perform poorly in depicting SDTF distribution. The poor performance of the maps can be attributed to two main factors: (1) poor spatial resolution, and (2) poor biome delimitation. Poor spatial resolution strongly limits the use of some of the maps in GIS applications, especially for areas with heterogeneous landscape such as the Andes. Whilst the Land Cover Map did not suffer from poor spatial resolution, it showed poor delimitation of biomes. The results highlight that delimiting structurally heterogeneous vegetation is difficult based on remote sensed data alone. A new refined working map of South American SDTF biome is proposed, derived using the Biome Distribution Modelling (BDM) approach where georeferenced herbarium data is used in conjunction with bioclimatic data. Conclusions Georeferenced specimen data play potentially an important role in biome mapping. Our study shows that herbarium data could be used as a way of ground-truthing biome maps in silico. The results also illustrate that herbarium data can be used to model vegetation maps through predictive modelling. The BDM approach is a promising new method in biome mapping, and could be particularly useful for mapping poorly known, fragmented, or degraded vegetation. We wish to highlight that biome delimitation is not an exact science, and that transparency is needed on how biomes are used as study units in macroevolutionary and ecological research. PMID:22115315

32 CFR 776.77 - Related investigations and actions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... omissions by covered attorneys may constitute professional misconduct, criminal misconduct, poor performance... to appropriate civil authority. (c) Poor performance of duty is properly addressed by the covered USG... criminal conduct or poor performance of duty involving covered attorneys. When, however, investigations...

Using Differentiated Instruction to Increase Mathematics Achievement in Elementary Students

ERIC Educational Resources Information Center

Faulkner, Jennifer H.

2013-01-01

As evidenced by the poor mathematics performance in American schools, specifically in the school district in the current study, providing identical educational opportunities for diverse students does not necessarily increase academic achievement for everyone. Differentiation is an instructional method that has been found to be successful in…

Quality Lies in the Eyes of the Beholder: A Mismatch between Student Evaluation and Peer Observation of Teaching

ERIC Educational Resources Information Center

Hassan, Salochana; Wium, Wouter

2014-01-01

The study described in this article was prompted by the poor performance of students in an "at risk subject" in a science faculty at a university in South Africa. Teacher performance could contribute to poor performance among students, therefore the performance of one of the science teachers whose students were performing poorly was…

Effect of Visual Media Use on School Performance: A Prospective Study1

PubMed Central

Sharif, Iman; Wills, Thomas A.; Sargent, James D.

2009-01-01

Purpose To identify mechanisms for the impact of visual media use on adolescents' school performance. Methods We conducted a 24-month, four-wave longitudinal telephone study of a national sample of 6,486 youth aged 10-14 years. Exposure Measures: Latent construct for screen exposure time (weekday time spent viewing television/playing videogames, presence of television in bedroom) and variables for movie content (proportion of PG13 and R movies viewed). Outcome Measure: Self and parent reports of grades in school. Effects of media exposures on change in school performance between baseline and 24 months were assessed using structural equation modeling. Information about hypothesized mediators (substance use, sensation-seeking, and school problem behavior) was obtained at baseline and at the16-month follow-up. Results Adjusted for baseline school performance, baseline levels of mediators, and a range of covariates, both screen exposure time and media content had adverse effects on change in school performance. Screen exposure had an indirect effect on poor school performance through increased sensation-seeking. Viewing more PG-13 and R-rated movies had indirect effects on poor school performance mediated through increases in substance use and sensation-seeking. R-rated viewing also had an indirect effect on poor school performance through increased school behavior problems. The effect sizes of exposure time and content on the intermediate variables and ultimately on school performance were similar to those for previously recognized determinants of these mediators – including household income, parenting style, and adolescents' self-control. Conclusions These aspects of visual media use adversely affect school performance by increasing sensation-seeking, substance use and school problem behavior. PMID:20123258

Disparities in Prevalence of Cardiometablic Risk Factors in Rural, Urban-Poor, and Urban-Middle Class Women in India

PubMed Central

Mohan, Indu; Gupta, Rajeev; Misra, Anoop; Sharma, Krishna Kumar; Agrawal, Aachu; Vikram, Naval K.; Sharma, Vinita; Shrivastava, Usha; Pandey, Ravindra M.

2016-01-01

Objective Urbanization is an important determinant of cardiovascular disease (CVD) risk. To determine location-based differences in CVD risk factors in India we performed studies among women in rural, urban-poor and urban middle-class locations. Methods Population-based cross-sectional studies in rural, urban-poor, and urban-middle class women (35–70y) were performed at multiple sites. We evaluated 6853 women (rural 2616, 5 sites; urban-poor 2008, 4 sites; urban middle-class 2229, 11 sites) for socioeconomic, lifestyle, anthropometric and biochemical risk factors. Descriptive statistics are reported. Results Mean levels of body mass index (BMI), waist circumference, waist-hip ratio (WHR), systolic BP, fasting glucose and cholesterol in rural, urban-poor and urban-middle class women showed significantly increasing trends (ANOVAtrend, p <0.001). Age-adjusted prevalence of diabetes and risk factors among rural, urban-poor and urban-middle class women, respectively was, diabetes (2.2, 9.3, 17.7%), overweight BMI ≥25 kg/m2 (22.5, 45.6, 57.4%), waist >80 cm (28.3, 63.4, 61.9%), waist >90 cm (8.4, 31.4, 38.2%), waist hip ratio (WHR) >0.8 (60.4, 90.7, 88.5), WHR>0.9 (13.0, 44.3, 56.1%), hypertension (31.6, 48.2, 59.0%) and hypercholesterolemia (13.5, 27.7, 37.4%) (Mantel Haenszel X2 ptrend <0.01). Inverse trend was observed for tobacco use (41.6, 19.6, 9.4%). There was significant association of hypertension, hypercholesterolemia and diabetes with overweight and obesity (adjusted R2 0.89–0.99). Conclusions There are significant location based differences in cardiometabolic risk factors in India. The urban-middle class women have the highest risk compared to urban-poor and rural. PMID:26881429

Parallel But Not Equivalent: Challenges and Solutions for Repeated Assessment of Cognition over Time

PubMed Central

Gross, Alden L.; Inouye, Sharon K.; Rebok, George W.; Brandt, Jason; Crane, Paul K.; Parisi, Jeanine M.; Tommet, Doug; Bandeen-Roche, Karen; Carlson, Michelle C.; Jones, Richard N.

2013-01-01

Objective Analyses of individual differences in change may be unintentionally biased when versions of a neuropsychological test used at different follow-ups are not of equivalent difficulty. This study’s objective was to compare mean, linear, and equipercentile equating methods and demonstrate their utility in longitudinal research. Study Design and Setting The Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE, N=1,401) study is a longitudinal randomized trial of cognitive training. The Alzheimer’s Disease Neuroimaging Initiative (ADNI, n=819) is an observational cohort study. Nonequivalent alternate versions of the Auditory Verbal Learning Test (AVLT) were administered in both studies. Results Using visual displays, raw and mean-equated AVLT scores in both studies showed obvious nonlinear trajectories in reference groups that should show minimal change, poor equivalence over time (ps≤0.001), and raw scores demonstrated poor fits in models of within-person change (RMSEAs>0.12). Linear and equipercentile equating produced more similar means in reference groups (ps≥0.09) and performed better in growth models (RMSEAs<0.05). Conclusion Equipercentile equating is the preferred equating method because it accommodates tests more difficult than a reference test at different percentiles of performance and performs well in models of within-person trajectory. The method has broad applications in both clinical and research settings to enhance the ability to use nonequivalent test forms. PMID:22540849

A visual tracking method based on improved online multiple instance learning

NASA Astrophysics Data System (ADS)

He, Xianhui; Wei, Yuxing

2016-09-01

Visual tracking is an active research topic in the field of computer vision and has been well studied in the last decades. The method based on multiple instance learning (MIL) was recently introduced into the tracking task, which can solve the problem that template drift well. However, MIL method has relatively poor performance in running efficiency and accuracy, due to its strong classifiers updating strategy is complicated, and the speed of the classifiers update is not always same with the change of the targets' appearance. In this paper, we present a novel online effective MIL (EMIL) tracker. A new update strategy for strong classifier was proposed to improve the running efficiency of MIL method. In addition, to improve the t racking accuracy and stability of the MIL method, a new dynamic mechanism for learning rate renewal of the classifier and variable search window were proposed. Experimental results show that our method performs good performance under the complex scenes, with strong stability and high efficiency.

Generalist Genes and Learning Disabilities: A Multivariate Genetic Analysis of Low Performance in Reading, Mathematics, Language and General Cognitive Ability in a Sample of 8000 12-Year-Old Twins

ERIC Educational Resources Information Center

Haworth, Claire M. A.; Kovas, Yulia; Harlaar, Nicole; Hayiou-Thomas, Marianna E.; Petrill, Stephen A.; Dale, Philip S.; Plomin, Robert

2009-01-01

Background: Our previous investigation found that the same genes influence poor reading and mathematics performance in 10-year-olds. Here we assess whether this finding extends to language and general cognitive disabilities, as well as replicating the earlier finding for reading and mathematics in an older and larger sample. Methods: Using a…

Sample-Poor Estimation of Order and Common Signal Subspace with Application to Fusion of Medical Imaging Data

PubMed Central

Levin-Schwartz, Yuri; Song, Yang; Schreier, Peter J.; Calhoun, Vince D.; Adalı, Tülay

2016-01-01

Due to their data-driven nature, multivariate methods such as canonical correlation analysis (CCA) have proven very useful for fusion of multimodal neurological data. However, being able to determine the degree of similarity between datasets and appropriate order selection are crucial to the success of such techniques. The standard methods for calculating the order of multimodal data focus only on sources with the greatest individual energy and ignore relations across datasets. Additionally, these techniques as well as the most widely-used methods for determining the degree of similarity between datasets assume sufficient sample support and are not effective in the sample-poor regime. In this paper, we propose to jointly estimate the degree of similarity between datasets and their order when few samples are present using principal component analysis and canonical correlation analysis (PCA-CCA). By considering these two problems simultaneously, we are able to minimize the assumptions placed on the data and achieve superior performance in the sample-poor regime compared to traditional techniques. We apply PCA-CCA to the pairwise combinations of functional magnetic resonance imaging (fMRI), structural magnetic resonance imaging (sMRI), and electroencephalogram (EEG) data drawn from patients with schizophrenia and healthy controls while performing an auditory oddball task. The PCA-CCA results indicate that the fMRI and sMRI datasets are the most similar, whereas the sMRI and EEG datasets share the least similarity. We also demonstrate that the degree of similarity obtained by PCA-CCA is highly predictive of the degree of significance found for components generated using CCA. PMID:27039696

5 CFR 362.207 - Withdrawal and readmission.

Code of Federal Regulations, 2010 CFR

2010-01-01

... withdraws from the Program for reasons that are not related to misconduct, poor performance, or suitability... misconduct, poor performance, or suitability, as determined by the agency, he/she will not be readmitted to... are not related to misconduct, poor performance, or suitability, he/she may petition the employing...

The association of students requiring remediation in the internal medicine clerkship with poor performance during internship.

PubMed

Hemann, Brian A; Durning, Steven J; Kelly, William F; Dong, Ting; Pangaro, Louis N; Hemmer, Paul A

2015-04-01

To determine whether the Uniformed Services University (USU) system of workplace performance assessment for students in the internal medicine clerkship at the USU continues to be a sensitive predictor of subsequent poor performance during internship, when compared with assessments in other USU third year clerkships. Utilizing Program Director survey results from 2007 through 2011 and U.S. Medical Licensing Examination (USMLE) Step 3 examination results as the outcomes of interest, we compared performance during internship for students who had less than passing performance in the internal medicine clerkship and required remediation, against students whose performance in the internal medicine clerkship was successful. We further analyzed internship ratings for students who received less than passing grades during the same time period on other third year clerkships such as general surgery, pediatrics, obstetrics and gynecology, family medicine, and psychiatry to evaluate whether poor performance on other individual clerkships were associated with future poor performance at the internship level. Results for this recent cohort of graduates were compared with previously published findings. The overall survey response rate for this 5 year cohort was 81% (689/853). Students who received a less than passing grade in the internal medicine clerkship and required further remediation were 4.5 times more likely to be given poor ratings in the domain of medical expertise and 18.7 times more likely to demonstrate poor professionalism during internship. Further, students requiring internal medicine remediation were 8.5 times more likely to fail USMLE Step 3. No other individual clerkship showed any statistically significant associations with performance at the intern level. On the other hand, 40% of students who successfully remediated and did graduate were not identified during internship as having poor performance. Unsuccessful clinical performance which requires remediation in the third year internal medicine clerkship at Uniformed Services University of the Health Sciences continues to be strongly associated with poor performance at the internship level. No significant associations existed between any of the other clerkships and poor performance during internship and Step 3 failure. The strength of this association with the internal medicine clerkship is most likely because of an increased level of sensitivity in detecting poor performance. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

Evaluation of the long-term performance of six alternative disposal methods for LLRW

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

Kossik, R.; Sharp, G.; Chau, T.

1995-12-31

The State of New York has carried out a comparison of six alternative disposal methods for low-level radioactive waste (LLRW). An important part of these evaluations involved quantitatively analyzing the long-term (10,000 yr) performance of the methods with respect to dose to humans, radionuclide concentrations in the environment, and cumulative release from the facility. Four near-surface methods (covered above-grade vault, uncovered above-grade vault, below-grade vault, augered holes) and two mine methods (vertical shaft mine and drift mine) were evaluated. Each method was analyzed for several generic site conditions applicable for the state. The evaluations were carried out using RIP (Repositorymore » Integration Program), an integrated, total system performance assessment computer code which has been applied to radioactive waste disposal facilities both in the U.S. (Yucca Mountain, WIPP) and worldwide. The evaluations indicate that mines in intact low-permeability rock and near-surface facilities with engineered covers generally have a high potential to perform well (within regulatory limits). Uncovered above-grade vaults and mines in highly fractured crystalline rock, however, have a high potential to perform poorly, exceeding regulatory limits.« less

District nursing workforce planning: a review of the methods.

PubMed

Reid, Bernie; Kane, Kay; Curran, Carol

2008-11-01

District nursing services in Northern Ireland face increasing demands and challenges which may be responded to by effective and efficient workforce planning and development. The aim of this paper is to critically analyse district nursing workforce planning and development methods, in an attempt to find a suitable method for Northern Ireland. A systematic analysis of the literature reveals four methods: professional judgement; population-based health needs; caseload analysis and dependency-acuity. Each method has strengths and weaknesses. Professional judgement offers a 'belt and braces' approach but lacks sensitivity to fluctuating patient numbers. Population-based health needs methods develop staffing algorithms that reflect deprivation and geographical spread, but are poorly understood by district nurses. Caseload analysis promotes equitable workloads but poorly performing district nursing localities may continue if benchmarking processes only consider local data. Dependency-acuity methods provide a means of equalizing and prioritizing workload but are prone to district nurses overstating factors in patient dependency or understating carers' capability. In summary a mixed method approach is advocated to evaluate and adjust the size and mix of district nursing teams using empirically determined patient dependency and activity-based variables based on the population's health needs.

Income gaps in self-rated poor health and its association with life expectancy in 245 districts of Korea

PubMed Central

2017-01-01

OBJECTIVES To examine the income gaps associated with self-rated poor health at the district level in Korea and to identify the geographical correlations between self-rated poor health, life expectancy, and the associated income gaps. METHODS We analyzed data for 1,578,189 participants from the Community Health Survey of Korea collected between 2008 and 2014. The age-standardized prevalence of self-rated poor health and the associated income gaps were calculated. Previously released data on life expectancy and the associated income gaps were also used. We performed correlation and regression analyses for self-rated poor health, life expectancy, and associated income gaps. RESULTS Across 245 districts, the median prevalence of self-rated poor health was 15.7% (95% confidence interval [CI], 14.6 to 16.8%), with interquartile range (IQR) of 3.1 percentage points (%p). The median interquintile gaps in the prevalence of self-rated poor health was 11.1%p (95% CI, 8.1 to 14.5%p), with IQR of 3.6%p. Pro-rich inequalities in self-rated health were observed across all 245 districts of Korea. The correlation coefficients for the association between self-rated poor health and the associated income gaps, self-rated poor health and life expectancy, and income gaps associated with self-rated poor health and life expectancy were 0.59, 0.78 and 0.55 respectively. CONCLUSIONS Income gaps associated with self-rated poor health were evident across all districts in Korea. The magnitude of income gaps associated with self-rated poor health was larger in the districts with greater prevalence of self-rated poor health. A strong correlation between self-rated poor health and life expectancy was also observed. PMID:28330335

Decompressive craniectomy in severe traumatic brain injury: prognostic factors and complications

PubMed Central

Grille, Pedro; Tommasino, Nicolas

2015-01-01

Objective To analyze the clinical characteristics, complications and factors associated with the prognosis of severe traumatic brain injury among patients who undergo a decompressive craniectomy. Methods Retrospective study of patients seen in an intensive care unit with severe traumatic brain injury in whom a decompressive craniectomy was performed between the years 2003 and 2012. Patients were followed until their discharge from the intensive care unit. Their clinical-tomographic characteristics, complications, and factors associated with prognosis (univariate and multivariate analysis) were analyzed. Results A total of 64 patients were studied. Primary and lateral decompressive craniectomies were performed for the majority of patients. A high incidence of complications was found (78% neurological and 52% nonneurological). A total of 42 patients (66%) presented poor outcomes, and 22 (34%) had good neurological outcomes. Of the patients who survived, 61% had good neurological outcomes. In the univariate analysis, the factors significantly associated with poor neurological outcome were postdecompressive craniectomy intracranial hypertension, greater severity and worse neurological state at admission. In the multivariate analysis, only postcraniectomy intracranial hypertension was significantly associated with a poor outcome. Conclusion This study involved a very severe and difficult to manage group of patients with high morbimortality. Intracranial hypertension was a main factor of poor outcome in this population. PMID:26340150

Managing Your Team's Weakest Link.

PubMed

Hills, Laura

2015-01-01

Do you have a poor-performing employee on your medical practice team? If so, you're not alone. Unfortunately, this is a problem that many medical practice managers face. This article describes the best strategies for managing your team's weakest link. It explores common yet very difficult circumstances that cause low employee performance and that test the patience, heart, and skills of a practice manager. It guides readers through a process of self-discovery to determine whether their negative biases or grudges may be causing employees to perform poorly. It suggests several possible other reasons for weak employee performance, including problems with the job, practice, leadership, communication, and fit between the employee and the job. This article also suggests the best strategy for communicating concerns about performance to the weakest-link employee. It offers guidance to practice managers about protecting their time and energy when handling a poor performer. It provides a simple formula for calculating the cost of a low-performing employee, 10 possible personal reasons for the employee's poor work performance, specific questions to ask to uncover the reasons for poor performance, and an eight-rule strategy for confronting poor performance effectively. Finally, this article offers practice managers a practical strategy for handling resistance from their weakest link, illustrated with a sample dialogue.

Predictors of survival of natural killer/T-cell lymphoma, nasal type, in a non-Asian population: a single cancer centre experience

PubMed Central

Vásquez, Jule; Serrano, Mariana; Lopez, Lourdes; Pacheco, Cristian; Quintana, Shirley

2016-01-01

Background Natural killer/T-cell lymphoma (NKTCL), part of T-cell and NK-cell neoplasms in the World Health Organisation (WHO) classification, is an aggressive lymphoma with poor prognosis more predominantly seen in Asian and South American countries. This study evaluates the factors associated with survival among patients with newly diagnosed NKTCL in Peru. Methods Information was abstracted from medical records (MR) for all NKTCL patients >13 years of age at the Instituto Nacional de Enfermedades Neoplasicas (INEN) between 2002 and 2011. The estimate of the survival curves was performed by the Kaplan-Meier method, and the difference was computed by the log-rank test. Results Around 226 MR were reviewed, 153 met the selection criteria, the median age was 40 years (14–84). The median progression-free survival (PFS) was 20 months, five year PFS was 42.6%, univariable analysis (UA) showed statistical significance (p < 0.05) for male sex, non-nasal primary site, advanced clinical stages, B symptoms, poor performance status, regional nodal involvement (RNI). In the multivariate analysis the only poor prognostic factors was primary non-nasal (Hazard ratio (HR) = 2.40, 95% confidence interval (CI) = 1.43– 4.02, P = 0.01). The median overall survival (OS) was 49 months, five year OS was 48.9%, UA showed statistical significance for non-nasal primary site, advanced clinical stages, B symptoms, lactate dehydrogenase (LDH) > normal, RNI and local tumour invasion. In the multivariate analysis, primary non-nasal was the only poor prognostic factor with HR = 2.57, 95% CI = 1.37–4.83, P = 0.03. Conclusions In Peru, OS of NKTCL is similar to other countries. This result suggests that non-nasal NKTCL is the only poor prognostic factor of OS and PFS. PMID:27994644

Characteristics and treatment outcomes of patients with multi-drug resistant tuberculosis at a tertiary care hospital in Peshawar, Pakistan

PubMed Central

Khan, Mazhar A.; Mehreen, Sumaira; Basit, Anila; Khan, Raza A.; Jan, Faheem; Ullah, Irfan; Ihtesham, Muhammad; Khan, Afsar; Ullah, Ubaid; Javaid, Arshad

2015-01-01

Objectives: To determine characteristics and treatment outcomes of multidrugs resistant tuberculosis (MDR-TB) patients and risk factors for poor outcomes in MDR-TB patients in a tertiary care hospital in Peshawar, Pakistan. Methods: This retrospective study was conducted at the Programmatic Management of Drug Resistant TB Unit, Lady Reading Hospital Peshawar, Pakistan and included all MDR-TB patients registered between January 2012 and December 2012. A special proforma was used for data collection. Analysis was performed using SPSS version 16, after exporting data from the proforma. Differences in proportions were assessed using Pearson’s Chi square test whereas for predictors of poor outcomes, multivariate logistic regression analysis with Wald Statistical criteria using backward elimination method was performed. Results: The treatment success rate was 74.3%. In univariate analysis, poor outcomes were associated in patients with age ≥44 years (odds ratio [OR]=0.250; 95% confidence interval [CI]: 0.114-0.519, p=0.001), rural residence (OR=0.417; 95% CI: 0.18-0.937, p=0.03), lung cavitation (OR=0.22; 95% CI, 0.007-0.067, p=0.001), resistance to second line drugs (SLD) (OR=3.441; 95% CI: 1.579-7.497, p=0.001), and resistance to ofloxacin (OR=2.944; 95% CI: 1.361-6.365, p=0.005); whereas multivariate logistic regression analysis, poor outcomes were associated in patients with age ≥44 years (OR=0.249, 95% CI: 0.075-0.828, p=0.023), rural residence (OR=0.143, 95% CI: 0.052-0.774, p=0.032), and cavitatory lungs (OR=0.022, 95% CI: 0.007-0.072, p=0.000). Conclusion: The MDR-TB patient needs special attention for better treatment outcomes. The presence of older age, rural area residence, resistance to ofloxacin, SLD resistance, and cavitary disease are independent prognostic factors for poor outcome in patients with MDR-TB. PMID:26620989

Development, validation, and comparison of ICA-based gradient artifact reduction algorithms for simultaneous EEG-spiral in/out and echo-planar fMRI recordings

PubMed Central

Ryali, S; Glover, GH; Chang, C; Menon, V

2009-01-01

EEG data acquired in an MRI scanner are heavily contaminated by gradient artifacts that can significantly compromise signal quality. We developed two new methods based on Independent Component Analysis (ICA) for reducing gradient artifacts from spiral in-out and echo-planar pulse sequences at 3T, and compared our algorithms with four other commonly used methods: average artifact subtraction (Allen et al. 2000), principal component analysis (Niazy et al. 2005), Taylor series (Wan et al. 2006) and a conventional temporal ICA algorithm. Models of gradient artifacts were derived from simulations as well as a water phantom and performance of each method was evaluated on datasets constructed using visual event-related potentials (ERPs) as well as resting EEG. Our new methods recovered ERPs and resting EEG below the beta band (< 12.5 Hz) with high signal-to-noise ratio (SNR > 4). Our algorithms outperformed all of these methods on resting EEG in the theta- and alpha-bands (SNR > 4); however, for all methods, signal recovery was modest (SNR ~ 1) in the beta-band and poor (SNR < 0.3) in the gamma-band and above. We found that the conventional ICA algorithm performed poorly with uniformly low SNR (< 0.1). Taken together, our new ICA-based methods offer a more robust technique for gradient artifact reduction when scanning at 3T using spiral in-out and echo-planar pulse sequences. We provide new insights into the strengths and weaknesses of each method using a unified subspace framework. PMID:19580873

Rarity and Incomplete Sampling in DNA-Based Species Delimitation.

PubMed

Ahrens, Dirk; Fujisawa, Tomochika; Krammer, Hans-Joachim; Eberle, Jonas; Fabrizi, Silvia; Vogler, Alfried P

2016-05-01

DNA-based species delimitation may be compromised by limited sampling effort and species rarity, including "singleton" representatives of species, which hampers estimates of intra- versus interspecies evolutionary processes. In a case study of southern African chafers (beetles in the family Scarabaeidae), many species and subclades were poorly represented and 48.5% of species were singletons. Using cox1 sequences from >500 specimens and ∼100 species, the Generalized Mixed Yule Coalescent (GMYC) analysis as well as various other approaches for DNA-based species delimitation (Automatic Barcode Gap Discovery (ABGD), Poisson tree processes (PTP), Species Identifier, Statistical Parsimony), frequently produced poor results if analyzing a narrow target group only, but the performance improved when several subclades were combined. Hence, low sampling may be compensated for by "clade addition" of lineages outside of the focal group. Similar findings were obtained in reanalysis of published data sets of taxonomically poorly known species assemblages of insects from Madagascar. The low performance of undersampled trees is not due to high proportions of singletons per se, as shown in simulations (with 13%, 40% and 52% singletons). However, the GMYC method was highly sensitive to variable effective population size ([Formula: see text]), which was exacerbated by variable species abundances in the simulations. Hence, low sampling success and rarity of species affect the power of the GMYC method only if they reflect great differences in [Formula: see text] among species. Potential negative effects of skewed species abundances and prevalence of singletons are ultimately an issue about the variation in [Formula: see text] and the degree to which this is correlated with the census population size and sampling success. Clade addition beyond a limited study group can overcome poor sampling for the GMYC method in particular under variable [Formula: see text] This effect was less pronounced for methods of species delimitation not based on coalescent models. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Did They Get It? The Role of Fidelity in Teaching English Learners

ERIC Educational Resources Information Center

Echevarria, Jana; Richards-Tutor, Catherine; Chinn, Vivan P.; Ratleff, Paige Ann

2011-01-01

Use of research-based practices for improving content area literacy of English learners is important both because of their growing numbers and their overall poor academic performance. However, how do we ensure that teachers are implementing proven methods with fidelity? This study shows the direct relationship between teachers' level of…

Comparison of Physical Therapy Anatomy Performance and Anxiety Scores in Timed and Untimed Practical Tests

ERIC Educational Resources Information Center

Schwartz, Sarah M.; Evans, Cathy; Agur, Anne M.R.

2015-01-01

Students in health care professional programs face many stressful tests that determine successful completion of their program. Test anxiety during these high stakes examinations can affect working memory and lead to poor outcomes. Methods of decreasing test anxiety include lengthening the time available to complete examinations or evaluating…

Our Accomplishments | NREL

Science.gov Websites

inspection methods use the natural vibration modes of the blade itself to enable vigorous shaking of blades ushers in designer wind turbine airfoils Every wing has an airfoil, which is a fancy word for the shape poor turbine performance, thanks to the fact that wind turbine blades operate in constant turbulence

Effectiveness of Read-Aloud Instruction on Motivation and Learning Strategy among Japanese College EFL Students

ERIC Educational Resources Information Center

Shinozuka, Katsumasa; Shibata, Setsue; Mizusawa, Yumiko

2017-01-01

Poor English performance among Japanese college EFL students has often been explained by grammar-translation and lecture-memorization instruction. This study investigated the effectiveness of a recently designed teaching method, namely, "The read-aloud instruction package," which consists of four major activities: Slash/chunked reading…

On the Irrelevance of Intelligence in Predicting Responsiveness to Reading Instruction

ERIC Educational Resources Information Center

Fuchs, Douglas; Young, Caresa L.

2006-01-01

There is increasingly negative sentiment against IQ-achievement discrepancy as a method to identify children with learning disabilities (LD) and, more broadly, intelligence as an explanation of poor academic performance. The evidence for this latter view was examined by reviewing 13 studies involving 1,542 children who were at risk or reading…

Exploring Sources of Variation in Romanian Science Achievement

ERIC Educational Resources Information Center

Istrate, Olimpius; Noveanu, Gabriela; Smith, Thomas M.

2006-01-01

The shift from a centrally-controlled to a market-oriented economy in the early 1990s put pressure on the Romanian education system to reform both the curriculum and methods of instruction employed in primary and secondary education. At least part of the pressure to implement educational reforms came from the relatively poor performance of…

Use of refractometry and colorimetry as field methods to rapidly assess antimalarial drug quality.

PubMed

Green, Michael D; Nettey, Henry; Villalva Rojas, Ofelia; Pamanivong, Chansapha; Khounsaknalath, Lamphet; Grande Ortiz, Miguel; Newton, Paul N; Fernández, Facundo M; Vongsack, Latsamy; Manolin, Ot

2007-01-04

The proliferation of counterfeit and poor-quality drugs is a major public health problem; especially in developing countries lacking adequate resources to effectively monitor their prevalence. Simple and affordable field methods provide a practical means of rapidly monitoring drug quality in circumstances where more advanced techniques are not available. Therefore, we have evaluated refractometry, colorimetry and a technique combining both processes as simple and accurate field assays to rapidly test the quality of the commonly available antimalarial drugs; artesunate, chloroquine, quinine, and sulfadoxine. Method bias, sensitivity, specificity and accuracy relative to high-performance liquid chromatographic (HPLC) analysis of drugs collected in the Lao PDR were assessed for each technique. The HPLC method for each drug was evaluated in terms of assay variability and accuracy. The accuracy of the combined method ranged from 0.96 to 1.00 for artesunate tablets, chloroquine injectables, quinine capsules, and sulfadoxine tablets while the accuracy was 0.78 for enterically coated chloroquine tablets. These techniques provide a generally accurate, yet simple and affordable means to assess drug quality in resource-poor settings.

Iron nutrition and premenopausal women: effects of poor iron status on physical and neuropsychological performance.

PubMed

McClung, James P; Murray-Kolb, Laura E

2013-01-01

Iron is a nutritionally essential trace element that functions through incorporation into proteins and enzymes, many of which contribute to physical and neuropsychological performance. Poor iron status, including iron deficiency (ID; diminished iron stores) and iron deficiency anemia (IDA; poor iron stores and diminished hemoglobin), affects billions of people worldwide. This review focuses on physical and neuropsychological outcomes associated with ID and IDA in premenopausal women, as the prevalence of ID and IDA is often greater in premenopausal women than other population demographics. Recent studies addressing the physiological effects of poor iron status on physical performance, including work productivity, voluntary activity, and athletic performance, are addressed. Similarly, the effects of iron status on neurological performance, including cognition, affect, and behavior, are summarized. Nutritional countermeasures for the prevention of poor iron status and the restoration of decrements in performance outcomes are described.

Diagnostic Performance of CT for Diagnosis of Fat-Poor Angiomyolipoma in Patients With Renal Masses: A Systematic Review and Meta-Analysis.

PubMed

Woo, Sungmin; Suh, Chong Hyun; Cho, Jeong Yeon; Kim, Sang Youn; Kim, Seung Hyup

2017-11-01

The purpose of this article is to systematically review and perform a meta-analysis of the diagnostic performance of CT for diagnosis of fat-poor angiomyolipoma (AML) in patients with renal masses. MEDLINE and EMBASE were systematically searched up to February 2, 2017. We included diagnostic accuracy studies that used CT for diagnosis of fat-poor AML in patients with renal masses, using pathologic examination as the reference standard. Two independent reviewers assessed the methodologic quality using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Sensitivity and specificity of included studies were calculated and were pooled and plotted in a hierarchic summary ROC plot. Sensitivity analyses using several clinically relevant covariates were performed to explore heterogeneity. Fifteen studies (2258 patients) were included. Pooled sensitivity and specificity were 0.67 (95% CI, 0.48-0.81) and 0.97 (95% CI, 0.89-0.99), respectively. Substantial and considerable heterogeneity was present with regard to sensitivity and specificity (I 2 = 91.21% and 78.53%, respectively). At sensitivity analyses, the specificity estimates were comparable and consistently high across all subgroups (0.93-1.00), but sensitivity estimates showed significant variation (0.14-0.82). Studies using pixel distribution analysis (n = 3) showed substantially lower sensitivity estimates (0.14; 95% CI, 0.04-0.40) compared with the remaining 12 studies (0.81; 95% CI, 0.76-0.85). CT shows moderate sensitivity and excellent specificity for diagnosis of fat-poor AML in patients with renal masses. When methods other than pixel distribution analysis are used, better sensitivity can be achieved.

Analysis of Free Modeling Predictions by RBO Aleph in CASP11

PubMed Central

Mabrouk, Mahmoud; Werner, Tim; Schneider, Michael; Putz, Ines; Brock, Oliver

2015-01-01

The CASP experiment is a biannual benchmark for assessing protein structure prediction methods. In CASP11, RBO Aleph ranked as one of the top-performing automated servers in the free modeling category. This category consists of targets for which structural templates are not easily retrievable. We analyze the performance of RBO Aleph and show that its success in CASP was a result of its ab initio structure prediction protocol. A detailed analysis of this protocol demonstrates that two components unique to our method greatly contributed to prediction quality: residue–residue contact prediction by EPC-map and contact–guided conformational space search by model-based search (MBS). Interestingly, our analysis also points to a possible fundamental problem in evaluating the performance of protein structure prediction methods: Improvements in components of the method do not necessarily lead to improvements of the entire method. This points to the fact that these components interact in ways that are poorly understood. This problem, if indeed true, represents a significant obstacle to community-wide progress. PMID:26492194

Understanding words, understanding numbers: an exploration of the mathematical profiles of poor comprehenders.

PubMed

Pimperton, Hannah; Nation, Kate

2010-06-01

Poor comprehenders are children who show significant deficits in their reading comprehension performance, despite average, or above-average word reading ability. To date, there have been no in-depth studies of the mathematical performance profiles of such children. This study aimed to explore the mathematical profiles of poor comprehenders. Given that language impairment is associated with difficulties with mathematics, and that poor comprehenders tend to have oral language weaknesses, we hypothesized that poor comprehenders would show relative weaknesses in aspects of mathematical performance. From a sample of 109 children aged 7-8 years, we selected 14 poor comprehenders and 14 controls with age-appropriate reading comprehension ability. The groups were matched on non-verbal ability, multiple measures of reading accuracy, and chronological age. We compared the performance of the group of poor comprehenders with that of the matched controls on two standardized measures of mathematical ability, one measuring procedural arithmetic prowess and the other tapping higher-level mathematical reasoning. Although there were no group differences in performance on the arithmetic measure, the poor comprehenders showed significantly lower scores than the controls on the mathematical reasoning task. The poor comprehenders exhibited impaired verbal ability relative to controls, with these differences in verbal ability associated with the group differences found on the test of mathematical reasoning. Poor comprehenders' deficits are not limited to the domain of literacy; their underlying profile of impairments also seems to selectively impact on certain components of mathematical ability.

Economic Assessment and Budgetary Impact of a Telemedicine Procedure and Spirometry Quality Control in the Primary Care Setting.

PubMed

Marina, Nuria; Bayón, Juan Carlos; López de Santa María, Elena; Gutiérrez, Asunción; Inchausti, Marta; Bustamante, Victor; Gáldiz, Juan B

2016-01-01

To evaluate the economic impact of a telemedicine procedure designed to improve the quality of lung function testing (LFT) in primary care in a public healthcare system, compared with the standard method. The economic impact of 9,039 LFTs performed in 51 health centers (2010-2013) using telespirometry (TS) compared to standard spirometry (SS) was studied. TS costs more per unit than SS (€47.80 vs. €39.70) (2013), but the quality of the TS procedure is superior (84% good quality, compared to 61% using the standard procedure). Total cost of TS was €431,974 (compared with €358,306€ for SS), generating an economic impact of €73,668 (2013). The increase in cost for good quality LFT performed using TS was €34,030 (2010) and €144,295 (2013), while the costs of poor quality tests fell by €15,525 (2010) and 70,627€ (2013). The cost-effectiveness analysis concludes that TS is 23% more expensive and 46% more effective. Healthcare costs consequently fall as the number of LFTs performed by TS rises. Avoiding poor quality, invalid LFTs generates savings that compensate for the increased costs of performing LFTs with TS, making it a cost-effective method. Copyright © 2014 SEPAR. Published by Elsevier Espana. All rights reserved.

Air-liquid interface exposure to aerosols of poorly soluble nanomaterials induces different biological activation levels compared to exposure to suspensions.

PubMed

Loret, Thomas; Peyret, Emmanuel; Dubreuil, Marielle; Aguerre-Chariol, Olivier; Bressot, Christophe; le Bihan, Olivier; Amodeo, Tanguy; Trouiller, Bénédicte; Braun, Anne; Egles, Christophe; Lacroix, Ghislaine

2016-11-03

Recently, much progress has been made to develop more physiologic in vitro models of the respiratory system and improve in vitro simulation of particle exposure through inhalation. Nevertheless, the field of nanotoxicology still suffers from a lack of relevant in vitro models and exposure methods to predict accurately the effects observed in vivo, especially after respiratory exposure. In this context, the aim of our study was to evaluate if exposing pulmonary cells at the air-liquid interface to aerosols of inhalable and poorly soluble nanomaterials generates different toxicity patterns and/or biological activation levels compared to classic submerged exposures to suspensions. Three nano-TiO 2 and one nano-CeO 2 were used. An exposure system was set up using VitroCell® devices to expose pulmonary cells at the air-liquid interface to aerosols. A549 alveolar cells in monocultures or in co-cultures with THP-1 macrophages were exposed to aerosols in inserts or to suspensions in inserts and in plates. Submerged exposures in inserts were performed, using similar culture conditions and exposure kinetics to the air-liquid interface, to provide accurate comparisons between the methods. Exposure in plates using classical culture and exposure conditions was performed to provide comparable results with classical submerged exposure studies. The biological activity of the cells (inflammation, cell viability, oxidative stress) was assessed at 24 h and comparisons of the nanomaterial toxicities between exposure methods were performed. Deposited doses of nanomaterials achieved using our aerosol exposure system were sufficient to observe adverse effects. Co-cultures were more sensitive than monocultures and biological responses were usually observed at lower doses at the air-liquid interface than in submerged conditions. Nevertheless, the general ranking of the nanomaterials according to their toxicity was similar across the different exposure methods used. We showed that exposure of cells at the air-liquid interface represents a valid and sensitive method to assess the toxicity of several poorly soluble nanomaterials. We underlined the importance of the cellular model used and offer the possibility to deal with low deposition doses by using more sensitive and physiologic cellular models. This brings perspectives towards the use of relevant in vitro methods of exposure to assess nanomaterial toxicity.

Unstructured Adaptive Meshes: Bad for Your Memory?

NASA Technical Reports Server (NTRS)

Biswas, Rupak; Feng, Hui-Yu; VanderWijngaart, Rob

2003-01-01

This viewgraph presentation explores the need for a NASA Advanced Supercomputing (NAS) parallel benchmark for problems with irregular dynamical memory access. This benchmark is important and necessary because: 1) Problems with localized error source benefit from adaptive nonuniform meshes; 2) Certain machines perform poorly on such problems; 3) Parallel implementation may provide further performance improvement but is difficult. Some examples of problems which use irregular dynamical memory access include: 1) Heat transfer problem; 2) Heat source term; 3) Spectral element method; 4) Base functions; 5) Elemental discrete equations; 6) Global discrete equations. Nonconforming Mesh and Mortar Element Method are covered in greater detail in this presentation.

Predicting Success in Psychological Statistics Courses.

PubMed

Lester, David

2016-06-01

Many students perform poorly in courses on psychological statistics, and it is useful to be able to predict which students will have difficulties. In a study of 93 undergraduates enrolled in Statistical Methods (18 men, 75 women; M age = 22.0 years, SD = 5.1), performance was significantly associated with sex (female students performed better) and proficiency in algebra in a linear regression analysis. Anxiety about statistics was not associated with course performance, indicating that basic mathematical skills are the best correlate for performance in statistics courses and can usefully be used to stream students into classes by ability. © The Author(s) 2016.

Feature Genes Selection Using Supervised Locally Linear Embedding and Correlation Coefficient for Microarray Classification

PubMed Central

Wang, Yun; Huang, Fangzhou

2018-01-01

The selection of feature genes with high recognition ability from the gene expression profiles has gained great significance in biology. However, most of the existing methods have a high time complexity and poor classification performance. Motivated by this, an effective feature selection method, called supervised locally linear embedding and Spearman's rank correlation coefficient (SLLE-SC2), is proposed which is based on the concept of locally linear embedding and correlation coefficient algorithms. Supervised locally linear embedding takes into account class label information and improves the classification performance. Furthermore, Spearman's rank correlation coefficient is used to remove the coexpression genes. The experiment results obtained on four public tumor microarray datasets illustrate that our method is valid and feasible. PMID:29666661

Feature Genes Selection Using Supervised Locally Linear Embedding and Correlation Coefficient for Microarray Classification.

PubMed

Xu, Jiucheng; Mu, Huiyu; Wang, Yun; Huang, Fangzhou

2018-01-01

The selection of feature genes with high recognition ability from the gene expression profiles has gained great significance in biology. However, most of the existing methods have a high time complexity and poor classification performance. Motivated by this, an effective feature selection method, called supervised locally linear embedding and Spearman's rank correlation coefficient (SLLE-SC 2 ), is proposed which is based on the concept of locally linear embedding and correlation coefficient algorithms. Supervised locally linear embedding takes into account class label information and improves the classification performance. Furthermore, Spearman's rank correlation coefficient is used to remove the coexpression genes. The experiment results obtained on four public tumor microarray datasets illustrate that our method is valid and feasible.

a Method for the Positioning and Orientation of Rail-Bound Vehicles in Gnss-Free Environments

NASA Astrophysics Data System (ADS)

Hung, R.; King, B. A.; Chen, W.

2016-06-01

Mobile Mapping System (MMS) are increasingly applied for spatial data collection to support different fields because of their efficiencies and the levels of detail they can provide. The Position and Orientation System (POS), which is conventionally employed for locating and orienting MMS, allows direct georeferencing of spatial data in real-time. Since the performance of a POS depends on both the Inertial Navigation System (INS) and the Global Navigation Satellite System (GNSS), poor GNSS conditions, such as in long tunnels and underground, introduce the necessity for post-processing. In above-ground railways, mobile mapping technology is employed with high performance sensors for finite usage, which has considerable potential for enhancing railway safety and management in real-time. In contrast, underground railways present a challenge for a conventional POS thus alternative configurations are necessary to maintain data accuracy and alleviate the need for post-processing. This paper introduces a method of rail-bound navigation to replace the role of GNSS for railway applications. The proposed method integrates INS and track alignment data for environment-independent navigation and reduces the demand of post-processing. The principle of rail-bound navigation is presented and its performance is verified by an experiment using a consumer-grade Inertial Measurement Unit (IMU) and a small-scale railway model. The method produced a substantial improvement in position and orientation for a poorly initialised system in centimetre positional accuracy. The potential improvements indicated by, and limitations of rail-bound navigation are also considered for further development in existing railway systems.

Delivering phonological and phonics training within whole-class teaching.

PubMed

Shapiro, Laura R; Solity, Jonathan

2008-12-01

Early, intensive phonological awareness and phonics training is widely held to be beneficial for children with poor phonological awareness. However, most studies have delivered this training separately from children's normal whole-class reading lessons. We examined whether integrating this training into whole class, mixed-ability reading lessons could impact on children with poor phonological awareness, whilst also benefiting normally developing readers. Teachers delivered the training within a broad reading programme to whole classes of children from Reception to the end of Year 1 (N=251). A comparison group of children received standard teaching methods (N=213). Children's literacy was assessed at the beginning of Reception, and then at the end of each year until 1 year post-intervention. The strategy significantly impacted on reading performance for normally developing readers and those with poor phonological awareness, vastly reducing the incidence of reading difficulties from 20% in comparison schools to 5% in intervention schools. Phonological and phonics training is highly effective for children with poor phonological awareness, even when incorporated into whole-class teaching.

Cerebrovascular function and cognition in childhood: a systematic review of transcranial doppler studies

PubMed Central

2014-01-01

Background The contribution of cerebrovascular function to cognitive performance is gaining increased attention. Transcranial doppler (TCD) is portable, reliable, inexpensive and extremely well tolerated by young and clinical samples. It enables measurement of blood flow velocity in major cerebral arteries at rest and during cognitive tasks. Methods We systematically reviewed evidence for associations between cognitive performance and cerebrovascular function in children (0-18 years), as measured using TCD. A total of 2778 articles were retrieved from PsychInfo, Pubmed, and EMBASE searches and 25 relevant articles were identified. Results Most studies investigated clinical groups, where decreased blood flow velocities in infants were associated with poor neurological functioning, and increased blood flow velocities in children with Sickle cell disease were typically associated with cognitive impairment and lower intelligence. Studies were also identified assessing autistic behaviour, mental retardation and sleep disordered breathing. In healthy children, the majority of studies reported cognitive processing produced lateralised changes in blood flow velocities however these physiological responses did not appear to correlate with behavioural cognitive performance. Conclusion Poor cognitive performance appears to be associated with decreased blood flow velocities in premature infants, and increased velocities in Sickle cell disease children using TCD methods. However knowledge in healthy samples is relatively limited. The technique is well tolerated by children, is portable and inexpensive. It therefore stands to make a valuable contribution to knowledge regarding the underlying functional biology of cognitive performance in childhood. PMID:24602446

The Impact of Quality Assurance Assessment on Diffusion Tensor Imaging Outcomes in a Large-Scale Population-Based Cohort

PubMed Central

Roalf, David R.; Quarmley, Megan; Elliott, Mark A.; Satterthwaite, Theodore D.; Vandekar, Simon N.; Ruparel, Kosha; Gennatas, Efstathios D.; Calkins, Monica E.; Moore, Tyler M.; Hopson, Ryan; Prabhakaran, Karthik; Jackson, Chad T.; Verma, Ragini; Hakonarson, Hakon; Gur, Ruben C.; Gur, Raquel E.

2015-01-01

Background Diffusion tensor imaging (DTI) is applied in investigation of brain biomarkers for neurodevelopmental and neurodegenerative disorders. However, the quality of DTI measurements, like other neuroimaging techniques, is susceptible to several confounding factors (e.g. motion, eddy currents), which have only recently come under scrutiny. These confounds are especially relevant in adolescent samples where data quality may be compromised in ways that confound interpretation of maturation parameters. The current study aims to leverage DTI data from the Philadelphia Neurodevelopmental Cohort (PNC), a sample of 1,601 youths ages of 8–21 who underwent neuroimaging, to: 1) establish quality assurance (QA) metrics for the automatic identification of poor DTI image quality; 2) examine the performance of these QA measures in an external validation sample; 3) document the influence of data quality on developmental patterns of typical DTI metrics. Methods All diffusion-weighted images were acquired on the same scanner. Visual QA was performed on all subjects completing DTI; images were manually categorized as Poor, Good, or Excellent. Four image quality metrics were automatically computed and used to predict manual QA status: Mean voxel intensity outlier count (MEANVOX), Maximum voxel intensity outlier count (MAXVOX), mean relative motion (MOTION) and temporal signal-to-noise ratio (TSNR). Classification accuracy for each metric was calculated as the area under the receiver-operating characteristic curve (AUC). A threshold was generated for each measure that best differentiated visual QA status and applied in a validation sample. The effects of data quality on sensitivity to expected age effects in this developmental sample were then investigated using the traditional MRI diffusion metrics: fractional anisotropy (FA) and mean diffusivity (MD). Finally, our method of QA is compared to DTIPrep. Results TSNR (AUC=0.94) best differentiated Poor data from Good and Excellent data. MAXVOX (AUC=0.88) best differentiated Good from Excellent DTI data. At the optimal threshold, 88% of Poor data and 91% Good/Excellent data were correctly identified. Use of these thresholds on a validation dataset (n=374) indicated high accuracy. In the validation sample 83% of Poor data and 94% of Excellent data was identified using thresholds derived from the training sample. Both FA and MD were affected by the inclusion of poor data in an analysis of age, sex and race in a matched comparison sample. In addition, we show that the inclusion of poor data results in significant attenuation of the correlation between diffusion metrics (FA and MD) and age during a critical neurodevelopmental period. We find higher correspondence between our QA method and DTIPrep for Poor data, but we find our method to be more robust for apparently high-quality images. Conclusion Automated QA of DTI can facilitate large-scale, high-throughput quality assurance by reliably identifying both scanner and subject induced imaging artifacts. The results present a practical example of the confounding effects of artifacts on DTI analysis in a large population-based sample, and suggest that estimates of data quality should not only be reported but also accounted for in data analysis, especially in studies of development. PMID:26520775

Comparative study on the measurement of learning outcomes after powerpoint presentation and problem based learning with discussion in family medicine amongst fifth year medical students.

PubMed

Khobragade, Sujata; Abas, Adinegara Lutfi; Khobragade, Yadneshwar Sudam

2016-01-01

Learning outcomes after traditional teaching methods were compared with problem-based learning (PBL) among fifth year medical students. Six students participated each in traditional teaching and PBL methods, respectively. Traditional teaching method involved PowerPoint (PPT) presentation and PBL included study on case scenario and discussion. Both methods were effective in improving performance of students. Postteaching, we did not find significant differences in learning outcomes between these two teaching methods. (1) Study was conducted with an intention to find out which method of learning is more effective; traditional or PBL. (2) To assess the level of knowledge and understanding in anemia/zoonotic diseases as against diabetes/hypertension. All the students posted from February 3, 2014, to March 14, 2014, participated in this study. Six students were asked to prepare and present a lecture (PPT) and subsequent week other six students were asked to present PBL. Both groups presented different topics. Since it was a pre- and post-test, same students were taken as control. To maintain uniformity and to avoid bias due cultural diversity, language etc., same questions were administered. After taking verbal consent, all 34 students were given pretest on anemia and zoonotic diseases. Then lecture (PPT) by six students on the same topic was given it followed by posttest questionnaire. Subsequent week pretest was conducted on hypertension and diabetes. Then case scenario presentation and discussion (PBL) was done by different six students followed by posttest. Both the methods were compared. Analysis was done manually and standard error of means and students t -test was used to find out statistical significance. We found statistically significant improvement in performance of students after PPT presentation as well as PBL. Both methods are equally effective. However, Pretest results of students in anemia and zoonotic diseases (Group A) were poor compared to pretest results of students in hypertension and diabetes (Group B). The students who participated in presentation did not influence their performance as they were covering a small part of the topic and there were no differences in their marks compared to other students. We did not find significant differences in outcome after teaching between PBL and traditional methods. Performances of students were poor in anemia and zoonotic diseases which need remedial teaching. Assessment may influence retention ability and performance.

Body Adiposity Index Performance in Estimating Body Fat Percentage in Colombian College Students: Findings from the FUPRECOL-Adults Study.

PubMed

Ramírez-Vélez, Robinson; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; Vivas, Andrés; Triana-Reina, Héctor Reynaldo; Martínez-Torres, Javier; Prieto-Benavides, Daniel Humberto; Carrillo, Hugo Alejandro; Ramos-Sepúlveda, Jeison Alexander; Villa-González, Emilio; García-Hermoso, Antonio

2017-01-17

Recently, a body adiposity index (BAI = (hip circumference)/((height)(1.5)) -18 ) was developed and validated in adult populations. The aim of this study was to evaluate the performance of BAI in estimating percentage body fat (BF%) in a sample of Colombian collegiate young adults. The participants were comprised of 903 volunteers (52% females, mean age = 21.4 years ± 3.3). We used the Lin's concordance correlation coefficient, linear regression, Bland-Altman's agreement analysis, concordance correlation coefficient ( ρc ) and the coefficient of determination ( R ²) between BAI, and BF%; by bioelectrical impedance analysis (BIA)). The correlation between the two methods of estimating BF% was R ² = 0.384, p < 0.001. A paired-sample t -test showed a difference between the methods (BIA BF% = 16.2 ± 3.1, BAI BF% = 30.0 ± 5.4%; p < 0.001). For BIA, bias value was 6.0 ± 6.2 BF% (95% confidence interval (CI) = -6.0 to 18.2), indicating that the BAI method overestimated BF% relative to the reference method. Lin's concordance correlation coefficient was poor ( ρc = 0.014, 95% CI = -0.124 to 0.135; p = 0.414). In Colombian college students, there was poor agreement between BAI- and BIA-based estimates of BF%, and so BAI is not accurate in people with low or high body fat percentage levels.

B-spline based image tracking by detection

NASA Astrophysics Data System (ADS)

Balaji, Bhashyam; Sithiravel, Rajiv; Damini, Anthony; Kirubarajan, Thiagalingam; Rajan, Sreeraman

2016-05-01

Visual image tracking involves the estimation of the motion of any desired targets in a surveillance region using a sequence of images. A standard method of isolating moving targets in image tracking uses background subtraction. The standard background subtraction method is often impacted by irrelevant information in the images, which can lead to poor performance in image-based target tracking. In this paper, a B-Spline based image tracking is implemented. The novel method models the background and foreground using the B-Spline method followed by a tracking-by-detection algorithm. The effectiveness of the proposed algorithm is demonstrated.

The relationship between corporate environmental performance and environmental disclosure: an empirical study in China.

PubMed

Meng, X H; Zeng, S X; Shi, Jonathan J; Qi, G Y; Zhang, Z B

2014-12-01

Based on a content analysis of 533 Chinese listed companies, this study examines how corporate environmental performance affects not only the level of detail of a company's environmental disclosures, but also what information is disclosed. The results show that (1) both poor and good performers have more disclosure than the median (i.e., "mixed") performers, which provides empirical evidence to support a nonlinear relationship between corporate environmental performance and environmental disclosure; (2) poor performers disclose more soft information on environmental performance than good performers, and good performers disclose more solid information; and (3) although poor performers increase disclosure after being exposed as environmental violators, they avoid disclosing negative environmental information, such as the violation and the associated penalties. This study provides additional evidence for a nonlinear relationship between environmental performance and disclosure in emerging markets, and suggests environmental disclosure may not be a valid signal to differentiate good performers from poor performers in contemporary China. Copyright © 2014 Elsevier Ltd. All rights reserved.

Determining team cognition from delay analysis using cross recurrence plot.

PubMed

Hajari, Nasim; Cheng, Irene; Bin Zheng; Basu, Anup

2016-08-01

Team cognition is an important factor in evaluating and determining team performance. Forming a team with good shared cognition is even more crucial for laparoscopic surgery applications. In this study, we analyzed the eye tracking data of two surgeons during a laparoscopic simulation operation, then performed Cross Recurrence Analysis (CRA) on the recorded data to study the delay behaviour for good performer and poor performer teams. Dual eye tracking data for twenty two dyad teams were recorded during a laparoscopic task and then the teams were divided into good performer and poor performer teams based on the task times. Eventually we studied the delay between two team members for good and poor performer teams. The results indicated that the good performer teams show a smaller delay comparing to poor performer teams. This study is compatible with gaze overlap analysis between team members and therefore it is a good evidence of shared cognition between team members.

Physical activity and cohabitation status moderate the link between diabetes mellitus and cognitive performance in a community-dwelling elderly population in Germany

PubMed Central

Buchmann, Nikolaus; Tegeler, Christina; Steinhagen-Thiessen, Elisabeth

2017-01-01

Aims/Hypothesis The increasing number of people with dementia and cognitive impairments makes it essential to detect and prevent modifiable risk factors of dementia. This study focuses on type 2 diabetes mellitus, especially on undiagnosed cases and their increased risk of cognitive impairment. Furthermore, the potential of physical activity and social integration to moderate the relation between diabetes and cognitive impairment is assessed. Methods We used cross-sectional data from 1299 participants of the Berlin Aging Study II (BASE-II) aged between 60 to 84 years and performed logistic regression models to analyze the association of diabetes status, physical activity, and cohabitation status with poor cognitive performance. Cognitive performance was measured with the Consortium to Establish a Registry for Alzheimer's Disease (CERAD)-Plus test battery. Results Undiagnosed diabetes (odds ratio (OR) = 2.12, p = 0.031), physical inactivity (OR = 1.43, p = 0.008) and non-cohabiting (OR = 1.58, p = 0.002) were associated with an increased likelihood of poor cognitive performance. The highest odds were observed in participants who suffered from undiagnosed or insulin-dependent diabetes and, in addition, were inactive (undiagnosed diabetes: OR = 3.44, p = 0.003; insulin-dependent diabetes: OR = 6.19, p = 0.019) or lived alone (undiagnosed diabetes: OR = 4.46, p = 0.006; insulin-dependent diabetes: OR = 6.46 p = 0.052). Physical activity and cohabiting appeared to be beneficial. Conclusions/Interpretation Physical activity and cohabitation status moderate the link between diabetes mellitus and cognitive performance. Special attention should be paid to undiagnosed and insulin-dependent diabetes cases, which have a particularly high risk of poor cognitive performance. PMID:29073237

Funnel plot control limits to identify poorly performing healthcare providers when there is uncertainty in the value of the benchmark.

PubMed

Manktelow, Bradley N; Seaton, Sarah E; Evans, T Alun

2016-12-01

There is an increasing use of statistical methods, such as funnel plots, to identify poorly performing healthcare providers. Funnel plots comprise the construction of control limits around a benchmark and providers with outcomes falling outside the limits are investigated as potential outliers. The benchmark is usually estimated from observed data but uncertainty in this estimate is usually ignored when constructing control limits. In this paper, the use of funnel plots in the presence of uncertainty in the value of the benchmark is reviewed for outcomes from a Binomial distribution. Two methods to derive the control limits are shown: (i) prediction intervals; (ii) tolerance intervals Tolerance intervals formally include the uncertainty in the value of the benchmark while prediction intervals do not. The probability properties of 95% control limits derived using each method were investigated through hypothesised scenarios. Neither prediction intervals nor tolerance intervals produce funnel plot control limits that satisfy the nominal probability characteristics when there is uncertainty in the value of the benchmark. This is not necessarily to say that funnel plots have no role to play in healthcare, but that without the development of intervals satisfying the nominal probability characteristics they must be interpreted with care. © The Author(s) 2014.

Application of Kinesio Taping method for newborn swallowing difficultly

PubMed Central

Lin, Chien-Lin; Wu, Wei-Ting; Chang, Ke-Vin; Lin, Hong-Yi; Chou, Li-Wei

2016-01-01

Abstract Background: Preterm infants are at an increased risk of sucking problems, swallowing difficulty, and poor nourishment. During the neonatal period, the neurobehavioral organization of a preterm baby is poor compared with that of appropriate gestational age infants. Kinesio Taping has been widely used for edema control, joint protection, and proprioception training. With the help of augmentation of the sensory input for muscle facilitation and inhibition through tapping, the coordination of the target muscle groups can be improved. Until now, no research is available on the use of Kinesio Taping for the swallowing difficulty of infant. Methods: We reported a preterm infant suffering from brain edema at birth and swallowing difficultly until 40 weeks. The swallowing reflex was delayed. Moreover, lip closure and rooting reflex combined with the dysfunction grade of jaw movement were poor. We performed KT methods on the baby under the theory of the direction of the tape for facilitate or inhibit the muscle. Result: After the Kinesio Taping treatment, the sucking function was improved with good lip closure.One week later, the baby was discharged without the use of an oral gastric tube. Conclusion: Kinesio Taping contributed significantly to the improvement of impaired sucking and swallowing and could be implemented as a regular rehabilitative approach for infants suffering from these difficulties. PMID:27495080

Evaluation of normalization methods in mammalian microRNA-Seq data

PubMed Central

Garmire, Lana Xia; Subramaniam, Shankar

2012-01-01

Simple total tag count normalization is inadequate for microRNA sequencing data generated from the next generation sequencing technology. However, so far systematic evaluation of normalization methods on microRNA sequencing data is lacking. We comprehensively evaluate seven commonly used normalization methods including global normalization, Lowess normalization, Trimmed Mean Method (TMM), quantile normalization, scaling normalization, variance stabilization, and invariant method. We assess these methods on two individual experimental data sets with the empirical statistical metrics of mean square error (MSE) and Kolmogorov-Smirnov (K-S) statistic. Additionally, we evaluate the methods with results from quantitative PCR validation. Our results consistently show that Lowess normalization and quantile normalization perform the best, whereas TMM, a method applied to the RNA-Sequencing normalization, performs the worst. The poor performance of TMM normalization is further evidenced by abnormal results from the test of differential expression (DE) of microRNA-Seq data. Comparing with the models used for DE, the choice of normalization method is the primary factor that affects the results of DE. In summary, Lowess normalization and quantile normalization are recommended for normalizing microRNA-Seq data, whereas the TMM method should be used with caution. PMID:22532701

Adult Outcome for Children with Autism

ERIC Educational Resources Information Center

Howlin, Patricia; Goode, Susan; Hutton, Jane; Rutter, Michael

2004-01-01

Background: Information on long-term prognosis in autism is limited. Outcome is known to be poor for those with an IQ below 50, but there have been few systematic studies of individuals with an IQ above this. Method: Sixty-eight individuals meeting criteria for autism and with a performance IQ of 50 or above in childhood were followed up as…

Toward Teaching Methods that Develop Learning and Enhance Problem Solving Skills in Engineering Students

ERIC Educational Resources Information Center

Loji, K.

2012-01-01

Problem solving skills and abilities are critical in life and more specifically in the engineering field. Unfortunately, significant numbers of South African students who are accessing higher education lack problem solving skills and this results in poor academic performance jeopardizing their progress especially from first to second year. On the…

A Study of the Relationship between Professional Development Evaluation and Middle School Mathematics Achievement

ERIC Educational Resources Information Center

Agnant Rogers, Myriam

2013-01-01

As a result of poor student performance, professional development has emerged as a key strategy for improving instruction and achievement. In times of reduced resources and increased accountability, schools must evaluate their efforts in order to make sound decisions about policy and practice. This mixed method study was designed to investigate…

The Longitudinal Impact of Cognitive Speed of Processing Training on Driving Mobility

ERIC Educational Resources Information Center

Edwards, Jerri D.; Myers, Charlsie; Ross, Lesley A.; Roenker, Daniel L.; Cissell, Gayla M.; McLaughlin, Alexis M.; Ball, Karlene K.

2009-01-01

Purpose: To examine how cognitive speed of processing training affects driving mobility across a 3-year period among older drivers. Design and Methods: Older drivers with poor Useful Field of View (UFOV) test performance (indicating greater risk for subsequent at-fault crashes and mobility declines) were randomly assigned to either a speed of…

The Impact of Question-Answer Relationships on Thai Reading Comprehension of Economically Disadvantaged Students: A Mixed Methods Study in Thailand

ERIC Educational Resources Information Center

Mongkolrat, Raveema

2017-01-01

Thailand's education has not succeeded in meeting the Ministry of Education Thailand's goals for Thai language. The problem manifests in students' substandard Thai reading comprehension. Results of the Thailand's standardized national test showed that students, especially those with economical disadvantages, have performed poorly in Thai reading…

Adding Debriefing to Objective Structured Clinical Examinations to Enhance Disability Cultural Sensitivity in Pharmacy Students

ERIC Educational Resources Information Center

Smith, Mark Joseph

2016-01-01

Debriefing was added to the design of an objective structured clinical examination (OSCE) after second-year pharmacy students performed poorly at considering patient disability in planning for patient care. This mixed-methods study examines secondary data to explore whether and how the addition of a debriefing to an OSCE impacted pharmacy…

Narrative Review of Statistical Reporting Checklists, Mandatory Statistical Editing, and Rectifying Common Problems in the Reporting of Scientific Articles.

PubMed

Dexter, Franklin; Shafer, Steven L

2017-03-01

Considerable attention has been drawn to poor reproducibility in the biomedical literature. One explanation is inadequate reporting of statistical methods by authors and inadequate assessment of statistical reporting and methods during peer review. In this narrative review, we examine scientific studies of several well-publicized efforts to improve statistical reporting. We also review several retrospective assessments of the impact of these efforts. These studies show that instructions to authors and statistical checklists are not sufficient; no findings suggested that either improves the quality of statistical methods and reporting. Second, even basic statistics, such as power analyses, are frequently missing or incorrectly performed. Third, statistical review is needed for all papers that involve data analysis. A consistent finding in the studies was that nonstatistical reviewers (eg, "scientific reviewers") and journal editors generally poorly assess statistical quality. We finish by discussing our experience with statistical review at Anesthesia & Analgesia from 2006 to 2016.

[Atherectomy for peripheral arterial disease].

PubMed

Londero, Louise Skovgaard; Høgh, Annette Langager; Lindholt, Jes Sanddal

2015-04-13

Symptomatic peripheral arterial disease is managed according to national and international guidelines and the number of vascular reconstructions performed each year has increased over the past decade mainly due to an increasing frequency of endovascular procedures. Atherectomy as an alternative to the established treatment of symptomatic peripheral arterial disease has recently been analysed in a Cochrane review. In Denmark, atherectomy is not performed and so far the evidence is poor as the method is not an alternative to the established treatment in this country.

Association of tic disorders with poor academic performance in central Spain: a population-based study.

PubMed

Cubo, Esther; Trejo, José; Ausín, Vanesa; Sáez, Sara; Delgado, Vanesa; Macarrón, Jesus; Cordero, José; Louis, Elan D; Kompoliti, Katie; Benito-León, Julián

2013-07-01

To analyze the association between tic disorders and poor academic performance in school-aged children. This was a cross-sectional, observational study conducted in a randomly selected sample of mainstream school-aged children (aged 6-16 years). The sampling frame included different types of schools and educational levels. Children with poor academic performance (eg, repeating a grade, special needs), and tic disorders (defined based on Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision criteria) were identified. Children with and without tics and children with and without poor academic performance were compared in terms of clinical features (ie, medical history and neurologic and psychiatric comorbidities), school, and environmental characteristics. Logistic regression analyses were performed using school performance (dependent variable) and tic disorders (independent variable), after adjusting for confounding variables. The study cohort comprised 1867 children (mean age, 10.9 + 2.9 years; 1007 males [53.9%]). Tics were present in 162 children (8.6%), and poor academic performance was noted in 223 (11.9%). Overall poor academic performance was associated with age (OR, 1.71; P < .0001), television viewing (OR, 5.33; P = .04), attention deficit hyperactivity disorder (OR, 1.38; P < .0001), and family history of school dysfunction (OR, 2.43; P = .02) and was negatively associated with higher IQ score (OR, 0.90; P < .0001) and tic disorders (OR, 0.29; P = .01). After adjusting for other covariates, the presence of tic disorders was not associated with poor academic performance in our cohort. Early academic support and modification of environmental characteristics are needed for children at higher risk for school dysfunction, to enhance academic performance. Copyright © 2013 Mosby, Inc. All rights reserved.

Poor Performance in Mathematics: Is There a Basis for a Self-Worth Explanation for Women?

ERIC Educational Resources Information Center

Thompson, Ted; Dinnel, Dale L.

2007-01-01

The self-worth theory of achievement motivation holds that in situations in which poor performance is likely to reveal low ability, certain students (known as self-worth protective students) intentionally withdraw effort in order to avoid the negative implications of poor performance in terms of damage to self-worth. In this study, evidence of…

Who Are the Low-Performing Students? PISA in Focus. No. 60

ERIC Educational Resources Information Center

OECD Publishing, 2016

2016-01-01

Far too many students around the world are trapped in a vicious cycle of poor performance and demotivation that leads only to more bad marks and further disengagement from school. Students who perform poorly at age 15 face a high risk of dropping out of school altogether. By the time they become young adults, poor proficiency in numeracy and…

Strategies to improve the performance of learners in a nursing college. Part II: Issues pertaining to management, attitudes and values.

PubMed

Waterson, E; Harms, E; Qupe, L; Maritz, J; Manning, M; Makobe, K; Chabeli, M

2006-05-01

This article forms part two of a bigger study that was conducted in a nursing college to explore and describe the reasons for the poor performance of learners. Part one of the study dealt with the issues pertaining to education, while this article (part two) seeks to describe issues pertaining to management, attitudes and values that lead to the poor performance of learners in the nursing college under study. A qualitative, exploratory and descriptive design that was contextual in nature was employed, and three focus groups interviews were conducted. Seven tutors formed one group while other two groups were formed by fourth-year learners following a comprehensive diploma course. All participants voluntarily participated in the study. Data was analyzed using the descriptive method of open coding in accordance with Tesch's protocol (in Creswell, 1994:154-156). Trustworthiness was ensured using the following principles: credibility, conformability, transferability and dependability (Lincoln & Guba 1985:290-326). Findings were categorized into issues pertaining to management, attitudes and values that had an influence on the poor performance of learners as follows: Inadequate resources and study facilities; policies that change frequently; tutors' dissatisfaction with regard to staff development, the lack of involvement by management and lack of management support, staff shortage and maldistribution of staff members; ineffective selection process of learners; inconsistent regulations, and too many of them; policies and procedures resulting in confusion and poor discipline. Attitudes and values: Tutors' lack of motivation and interest, lack of respect by learners and no team work among tutors. Through a conceptualization process and the recommendations by participants, strategies to improve the learners' performance were described. It is recommended that these strategies be submitted to the staff development committee for implementation and future follow-up research be undertaken to determine the effectiveness of the strategies. It is also recommended that other nursing colleges replicate the study within their context.

RELATIONSHIP OF PRESEASON MOVEMENT SCREENS WITH OVERUSE SYMPTOMS IN COLLEGIATE BASEBALL PLAYERS

PubMed Central

Clifton, Daniel R.; Onate, James A.; Ramsey, Vincent K.; Cromartie, Fred

2017-01-01

Background: The shoulder mobility screen of the Functional Movement Screen™ (FMS™) and the upper extremity patterns of the Selective Functional Movement Assessment (SFMA) assess global, multi-joint movement capabilities in the upper-extremities. Identifying which assessment can most accurately determine if baseball players are at an increased risk of experiencing overuse symptoms in the shoulder or elbow throughout a competitive season may reduce throwing-related injuries requiring medical attention. Purpose: The purpose of this study was to determine if preseason FMS™ or SFMA scores were related to overuse severity scores in the shoulder or elbow during the preseason and competitive season. Study design: Cohort study. Methods: Sixty healthy, male, Division III collegiate baseball players (mean age = 20.1 ± 2.0 years) underwent preseason testing using the FMS™ shoulder mobility screen, and SFMA upper extremity patterns. Their scores were dichotomized into good and bad movement scores, and were compared to weekly questionnaires registering overuse symptoms and pain severity in the shoulder or elbow during the season. Results: Poor FMS™ performance was associated with an increased likelihood of experiencing at least one overuse symptom during the preseason independent of grade and position (adjusted odds ratio [OR] = 5.14, p = 0.03). Poor SFMA performance was associated with an increased likelihood of experiencing at least one overuse symptom during the preseason (adjusted OR = 6.10, p = 0.03) and during the competitive season (adjusted OR = 17.07, p = 0.03) independent of grade and position. Conclusion: FMS™ shoulder mobility and SFMA upper extremity pattern performance were related to the likelihood of experiencing overuse symptoms during a baseball season. Participants with poor FMSTM performances may be more likely to experience at least one overuse symptom in their shoulder or elbow during the preseason. Additionally, individuals with poor SFMA performances may be more likely to report overuse symptoms during the preseason or competitive season. Level of evidence: Level 3 PMID:29158957

[The year 2000: one billion couples of child-bearing age].

PubMed

Lintong, L J

1988-04-01

Out of 1 billion couples there are only 124 million who use modern and effective contraceptives. World abortions number 33 million/year. 250 million sexually active women of child-bearing age in developing countries outside China do not use modern and effective contraceptives. Fertility control costs on the average US$2.5 billion a year in each developing country, 20% of which is assistance from developed countries. Expanding the family planning service to the 250 million sexually active child-bearing aged women costs an additional U.S. $5 billion yearly. A family planning accessibility survey was conducted by the Population Crisis Committee. PCC divided the countries into 2 categories: Developed and developing countries. The 110 countries (15 developed and 95 developing) covered 96% of the world population. The survey placed the countries in 5 classes according to accessibility levels: Excellent, good, fair, poor, very poor. The developed countries were analyzed according to effective contraceptive methods, service to the poor and minorities, sex education in the schools, and family planning information and advertisement. The developing countries were analyzed according to effective contraceptive methods, performance of service and distribution, public information and education, private sector participation, government finance and policies. Of the 15 developed countries, 43% were excellent, 22% good, 24% fair, and 2% poor. Of the 95 developing countries, 5 were excellent, 10 good, 16 fair, and 64 either poor or very poor countries in respect to family planning accessibility. In the face of a population explosion in the year 2000, many countries lack of government support for family planning programs. After 30 years of world effort in population control, half of the world population still has no effective family planning services.

Design of maintainable drains for earth retaining structures : final report and design guide.

DOT National Transportation Integrated Search

2017-04-01

Poor drainage is by far the most common cause of poor performance for earth retention systems. Poor performance includes burdensome serviceability problems that can progress to outright failure of the earth retention system if not addressed. : A comm...

Assessment of management approaches in a public water utility: A case study of the Namibia water corporation (NAMWATER)

NASA Astrophysics Data System (ADS)

Ndokosho, Johnson; Hoko, Zvikomborero; Makurira, Hodson

More than 90% of urban water supply and sanitation services in developing countries are provided by public organizations. However, public provision of services has been inherently inefficient. As a result a number of initiatives have emerged in recent years with a common goal to improve service delivery. In Namibia, the water sector reform resulted in the creation of a public utility called the Namibia Water Corporation (NAMWATER) which is responsible for bulk water supply countrywide. Since its inception in 1998, NAMWATER has been experiencing poor financial performance. This paper presents the findings of a case study that compared the management approaches of NAMWATER to the New Public Management (NPM) paradigm. The focus of the NPM approach is for the public water sector to mirror private sector methods of management so that public utilities can accrue the benefits of effectiveness, efficiency and flexibility often associated with private sector. The study tools used were a combination of literature review, interviews and questionnaires. It was found out that NAMWATER has a high degree of autonomy in its operations, albeit government approved tariffs and sourcing of external financing. The utility reports to government annually to account for results. The utility embraces a notion of good corporate culture and adheres to sound management practices. NAMWATER demonstrated a strong market-orientation indicated by the outsourcing of non-core functions but benchmarking was poorly done. NAMWATER’s customer-orientation is poor as evidenced by the lack of customer care facilities. NAMWATER’s senior management delegated operational authority to lower management to facilitate flexibility and eliminate bottlenecks. The lower management is in turn held accountable for performance by the senior management. There are no robust methods of ensuring sufficient accountability indicated by absence of performance contracts or service level agreements. It was concluded that NAMWATER’s management approaches adhere to the NPM paradigm but some NPM core-ideas such as customer orientation and external accountability (performance contracts) were visibly missing.

Low BRMS1 expression promotes nasopharyngeal carcinoma metastasis in vitro and in vivo and is associated with poor patient survival

PubMed Central

2012-01-01

Background Breast cancer metastasis suppressor 1 (BRMS1) is a metastasis suppressor gene. This study aimed to investigate the impact of BRMS1 on metastasis in nasopharyngeal carcinoma (NPC) and to evaluate the prognostic significance of BRMS1 in NPC patients. Methods BRMS1 expression was examined in NPC cell lines using quantitative reverse transcription-polymerase chain reaction and Western blotting. NPC cells stably expressing BRMS1 were used to perform wound healing and invasion assays in vitro and a murine xenograft assay in vivo. Immunohistochemical staining was performed in 274 paraffin-embedded NPC specimens divided into a training set (n = 120) and a testing set (n = 154). Results BRMS1 expression was down-regulated in NPC cell lines. Overexpression of BRMS1 significantly reversed the metastatic phenotype of NPC cells in vitro and in vivo. Importantly, low BRMS1 expression was associated with poor distant metastasis-free survival (DMFS, P < 0.001) and poor overall survival (OS, P < 0.001) in the training set; these results were validated in the testing set and overall patient population. Cox regression analysis demonstrated that low BRMS1 expression was an independent prognostic factor for DMFS and OS in NPC. Conclusions Low expression of the metastasis suppressor BRMS1 may be an independent prognostic factor for poor prognosis in NPC patients. PMID:22931099

Choosing a design to fit the situation: how to improve specificity and positive predictive values using Bayesian lot quality assurance sampling.

PubMed

Olives, Casey; Pagano, Marcello

2013-02-01

Lot Quality Assurance Sampling (LQAS) is a provably useful tool for monitoring health programmes. Although LQAS ensures acceptable Producer and Consumer risks, the literature alleges that the method suffers from poor specificity and positive predictive values (PPVs). We suggest that poor LQAS performance is due, in part, to variation in the true underlying distribution. However, until now the role of the underlying distribution in expected performance has not been adequately examined. We present Bayesian-LQAS (B-LQAS), an approach to incorporating prior information into the choice of the LQAS sample size and decision rule, and explore its properties through a numerical study. Additionally, we analyse vaccination coverage data from UNICEF's State of the World's Children in 1968-1989 and 2008 to exemplify the performance of LQAS and B-LQAS. Results of our numerical study show that the choice of LQAS sample size and decision rule is sensitive to the distribution of prior information, as well as to individual beliefs about the importance of correct classification. Application of the B-LQAS approach to the UNICEF data improves specificity and PPV in both time periods (1968-1989 and 2008) with minimal reductions in sensitivity and negative predictive value. LQAS is shown to be a robust tool that is not necessarily prone to poor specificity and PPV as previously alleged. In situations where prior or historical data are available, B-LQAS can lead to improvements in expected performance.

Collocated electrodynamic FDTD schemes using overlapping Yee grids and higher-order Hodge duals

NASA Astrophysics Data System (ADS)

Deimert, C.; Potter, M. E.; Okoniewski, M.

2016-12-01

The collocated Lebedev grid has previously been proposed as an alternative to the Yee grid for electromagnetic finite-difference time-domain (FDTD) simulations. While it performs better in anisotropic media, it performs poorly in isotropic media because it is equivalent to four overlapping, uncoupled Yee grids. We propose to couple the four Yee grids and fix the Lebedev method using discrete exterior calculus (DEC) with higher-order Hodge duals. We find that higher-order Hodge duals do improve the performance of the Lebedev grid, but they also improve the Yee grid by a similar amount. The effectiveness of coupling overlapping Yee grids with a higher-order Hodge dual is thus questionable. However, the theoretical foundations developed to derive these methods may be of interest in other problems.

Association between overweight/obesity and academic performance in South Korean adolescents.

PubMed

Kim, Jong-Hyuck; So, Wi-Young

2013-12-01

The purpose of this study was to examine the relationship between academic performance and obesity/overweight among South Korean adolescents. Our data set included 72,399 adolescents in grades 7-12 who had participated in the 5th Korea Youth Risk Behaviour Web-based Survey (KYRBWS-V) in 2009. We assessed the association between academic performance and body mass index (BMI), using multivariate logistic regression analysis after adjusting for covariates such as age, parents' education level, economic status, mental stress experienced, sleep duration, frequency of muscle-strengthening exercises, smoking and drinking behaviour, and vigorous and moderate physical activity (PA). For boys, being overweight (compared with being of normal weight) had a significantly greater odds of poor academic performance (OR=1.182, 95% Cl 1.052-1.329, p=0.005). Obese boys had 1.182 (1.048-1.332, p=0.006), 1.461 (1.294-1.648, p<0.001), and 1.443(1.256-1.657, p<0.001) greater odds of having average, poor, and very poor performance, respectively. In the analysis for girls, overweight girls had 1.314 (1.124-1.536, p<0.001) and 1.296 (1.084-1.548, p=0.004) greater odds of having poor and very poor academic performance, respectively. Finally, obese girls had 1.374 (1.098-1.718, p=0.005), 1.672 (1.339-2.089, p<0.001), and 1.887 (1.478-2.409, p<0.001) greater odds of having average, poor, or very poor academic performance, respectively. Thus, overweight/obesity was negatively associated with academic performance in both boys and girls. The results of this study indicate that adolescents would benefit from weight management to prevent obesity and, possibly, improve academic performance.

Research on frequency control strategy of interconnected region based on fuzzy PID

NASA Astrophysics Data System (ADS)

Zhang, Yan; Li, Chunlan

2018-05-01

In order to improve the frequency control performance of the interconnected power grid, overcome the problems of poor robustness and slow adjustment of traditional regulation, the paper puts forward a frequency control method based on fuzzy PID. The method takes the frequency deviation and tie-line deviation of each area as the control objective, takes the regional frequency deviation and its deviation as input, and uses fuzzy mathematics theory, adjusts PID control parameters online. By establishing the regional frequency control model of water-fire complementary power generation in MATLAB, the regional frequency control strategy is given, and three control modes (TBC-FTC, FTC-FTC, FFC-FTC) are simulated and analyzed. The simulation and experimental results show that, this method has better control performance compared with the traditional regional frequency regulation.

A new method for determining the mycelial weight of the koji-mold Aspergillus oryzae by measuring its glycosylceramide content.

PubMed

Ferdouse, Jannatul; Miyagawa, Miyuki; Hirano, Mikako; Kitajima, Yuka; Inaba, Shigeki; Kitagaki, Hiroshi

2018-06-21

At present, the quantitation of the mycelial weight of the industrially important non-pathogenic fungus Aspergillus oryzae, which is used for manufacturing koji, is performed by quantitating N-acetylglucosamine. However, since N-acetylglucosamine is a cell wall component, the extraction procedure is costly and tedious, and its quantitative performance is poor. Here, we report a novel method for the quantitation of A. oryzae mycelial weight. The amount of glycosylceramide significantly correlated with both the mycelial weight of A. oryzae and the amount of N-acetylglucosamine, an established index of the mycelial weight of A. oryzae in koji. This new method is simple and efficient and can be used in the brewing and food industries to determine the mycelial weight of A. oryzae.

Neurologic examination at 24–48 hours predicts functional outcomes in basilar artery occlusion stroke

PubMed Central

Rangaraju, Srikant; Jovin, Tudor G.; Frankel, Michael; Schonewille, Wouter J.; Algra, Ale; Kappelle, L. Jaap; Nogueira, Raul G.

2016-01-01

Background and Purpose Accurate long-term outcome prognostication in basilar artery occlusion (BAO) strokes may guide clinical management in the subacute stage. We determine the prognostic value of the follow-up neurologic examination using the NIH stroke scale (NIHSS) and identify 24–48 hours NIHSS risk categories in BAO patients. Methods Participants of an observational registry of radiologically-confirmed acute BAO (BASICS) with prospectively collected 24–48 hours NIHSS and 1-month modified Rankin Scale (mRS) scores were included. Uni- and multivariable modeling were performed to identify independent predictors of poor outcome. Predictive powers of baseline and 24–48 hour NIHSS for poor outcome (mRS 4–6) and 1-month mortality were determined by Receiver Operating Characteristic analyses. Classification and regression tree (CART) analysis was performed to identify risk groups. Results 376 of 619 BASICS participants were included of whom 65.4% had poor outcome. In multivariable analyses, 24–48 hours NIHSS (OR=1.28 [1.21–1.35]), history of minor stroke (OR=2.64 [1.04–6.74], time to treatment >6 hours (OR=3.07 [1.35–6.99]) and age (OR 1.02 [0.99–1.04] were retained in the final model as predictors of poor outcome. Prognostic power of 24–48 hours NIHSS was higher than baseline NIHSS for 1-month poor outcome (AUC 0.92 vs. 0.75) and mortality (AUC 0.85 vs. 0.72). CART analysis identified five 24–48 hour NIHSS risk categories with poor outcome rates of 9.4% (NIHSS 0–4), 36% (NIHSS 5–11), 84.3% (NIHSS 12–22), 96.1% (NIHSS 23–27) and 100% (NIHSS≥28). Conclusion 24–48 hour NIHSS accurately predicts 1-month poor outcome and mortality and represents a clinically valuable prognostic tool for the care of BAO patients. PMID:27586683

Prospective Evaluation of Pretreatment Executive Cognitive Impairment and Depression in Patients Referred for Radiotherapy

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

Fuller, Clifton D.; Graduate Division of Radiological Sciences, University of Texas Health Science Center at San Antonio, San Antonio, TX; Department of Radiation Medicine, Oregon Health and Science University, Portland, OR

Purpose: Cancer patients are at risk of cognitive impairment and depression. We sought to ascertain the prevalence of executive, visuospatial, memory, and general cognitive performance deficits before radiotherapy in a radiation oncology clinic referral population and correlate the neurocognitive measures with the depression symptom burden. Methods and Materials: A total of 122 sequential patients referred for radiotherapy evaluation were administered a test battery composed of the Executive Interview (EXIT25), Executive Clock Drawing Task (CLOX1 and CLOX2), Mini Mental State Examination (MMSE), Memory Impairment Screen (MIS), and Geriatric Depression Scale (GDS). The mean age {+-} standard deviation was 58 {+-} 17more » years. Of 122 patients, 24 (20%) had been referred for breast cancer, 21 (17%) for gastrointestinal cancer, 17 (14%) for genitourinary disease, and 8 (7%) for brain lesions; the rest were a variety of tumor sites. The cognitive performance among the tumor cohorts was compared using Bonferroni-corrected analysis of variance and Tukey-Kramer tests. Pearson correlation coefficients were determined between each cognitive instrument and the GDS. Results: Of the 122 patients, 52 (43%) exhibited a detectable executive cognition decrement on one or more test measures. Five percent had poor memory performance (MIS), 18% had poor visuospatial performance (CLOX2), and 13% had poor global cognition (MMSE). Patients with brain tumors performed substantially worse on the EXIT25. No between-group differences were found for CLOX1, CLOX2, MIS, or GDS performance. The EXIT25 scores correlated significantly with the GDS scores (r = 0.26, p = 0.005). Conclusions: The results of this study have shown that patients referred for radiotherapy exhibit cognitive impairment profiles comparable to those observed in acutely ill medical inpatients. Executive control impairment appears more prevalent than global cognitive deficits, visuospatial impairment, or depression.« less

Clinical Rating of Movement-Pattern Quality in Patients With Femoroacetabular Impingement Syndrome: A Methodological Study.

PubMed

Casartelli, Nicola C; Maffiuletti, Nicola A; Brunner, Romana; Büchi, Marcel; Sutter, Reto; Pfirrmann, Christian W; Naal, Florian D; Leunig, Michael; Bizzini, Mario

2018-04-01

Study Design Cross-sectional study. Objectives To evaluate intrarater and interrater agreement among physical therapists with different clinical experience in performing a visual rating of movement-pattern quality of patients with femoroacetabular impingement (FAI) syndrome using a semi-quantitative scale. Background Visual rating of movement patterns in patients with FAI syndrome is of interest, because poor control of dynamic hip motion is frequently noted. Methods A video camera was used to record the performance of 34 patients with FAI syndrome performing single-limb standing, squat, frontal lunge, hop lunge, bridge, and plank. Visual rating of movement, as recorded on video, was performed by a highly experienced, a moderately experienced, and a novice physical therapist on 2 occasions using a semi-quantitative scale. Hip abductor strength was assessed using dynamometry, and hip pain and function were assessed with a patient-reported questionnaire. Intrarater and interrater agreement among physical therapists was evaluated using Gwet's agreement coefficient 1. Construct validity was evaluated as the association between physical therapists' rating and patients' hip abductor strength, pain, and function. Results Good intrarater and interrater agreement was observed in the highly experienced and moderately experienced physical therapists when rating single-limb standing, bridge, and plank. Poor to moderate intrarater and interrater agreement was found when they rated squat, frontal lunge, and hop lunge. Poor performers, as rated by the highly experienced physical therapist only, demonstrated lower hip abductor strength (P<.05), and similar hip pain and hip function compared to those of good performers. Conclusion Movement-pattern quality of patients with FAI syndrome should be rated by a highly experienced physical therapist. J Orthop Sports Phys Ther 2018;48(4):260-269. doi:10.2519/jospt.2018.7840.

Enhanced solubility of piperine using hydrophilic carrier-based potent solid dispersion systems.

PubMed

Thenmozhi, Kathavarayan; Yoo, Young Je

2017-09-01

Piperine alkaloid, an important constituent of black pepper, exhibits numerous therapeutic properties, whereas its usage as a drug is limited due to its poor solubility in aqueous medium, which leads to poor bioavailability. Herein, a new method has been developed to improve the solubility of this drug based on the development of solid dispersions with improved dissolution rate using hydrophilic carriers such as sorbitol (Sor), polyethylene glycol (PEG) and polyvinyl pyrrolidone K30 (PVP) by solvent method. Physical mixtures of piperine and carriers were also prepared for comparison. The physicochemical properties of the prepared solid dispersions were examined using SEM, TEM, DSC, XRD and FT-IR. In vitro dissolution profile of the solid dispersions was recorded and compared with that of the pure piperine and physical mixtures. The effect of these carriers on the aqueous solubility of piperine has been investigated. The solid dispersions of piperine with Sor, PEG and PVP exhibited superior performance for the dissolution of piperine with a drug release of 70%, 76% and 89%, respectively after 2 h compared to physical mixtures and pure piperine, which could be due to its transformation from crystalline to amorphous form as well as the attachment of hydrophilic carriers to the surface of poorly water-soluble piperine. Results suggest that the piperine solid dispersions prepared with improved in vitro release exhibit potential advantage in delivering poorly water-soluble piperine as an oral supplement.

Sleep quantity, quality, and insomnia symptoms of medical students during clinical years

PubMed Central

Alsaggaf, Mohammed A.; Wali, Siraj O.; Merdad, Roah A.; Merdad, Leena A.

2016-01-01

Objectives: To determine sleep habits and sleep quality in medical students during their clinical years using validated measures; and to investigate associations with academic performance and psychological stress. Methods: In this cross-sectional study, medical students (n=320) were randomly selected from a list of all enrolled clinical-year students in a Saudi medical school from 2011-2012. Students filled a questionnaire including demographic and lifestyle factors, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and Perceived Stress Scale. Results: Students acquired on average, 5.8 hours of sleep each night, with an average bedtime at 01:53. Approximately 8% reported acquiring sleep during the day, and not during nighttime. Poor sleep quality was present in 30%, excessive daytime sleepiness (EDS) in 40%, and insomnia symptoms in 33% of students. Multivariable regression models revealed significant associations between stress, poor sleep quality, and EDS. Poorer academic performance and stress were associated with symptoms of insomnia. Conclusion: Sleep deprivation, poor sleep quality, and EDS are common among clinical years medical students. High levels of stress and the pressure of maintaining grade point averages may be influencing their quality of sleep. PMID:26837401

Development of an SPE/CE method for analyzing HAAs

USGS Publications Warehouse

Zhang, L.; Capel, P.D.; Hozalski, R.M.

2007-01-01

The haloacetic acid (HAA) analysis methods approved by the US Environmental Protection Agency involve extraction and derivatization of HAAs (typically to their methyl ester form) and analysis by gas chromatography (GC) with electron capture detection (ECD). Concerns associated with these methods include the time and effort of the derivatization process, use of potentially hazardous chemicals or conditions during methylation, poor recoveries because of low extraction efficiencies for some HAAs or matrix effects from sulfate, and loss of tribromoacetic acid because of decarboxylation. The HAA analysis method introduced here uses solid-phase extraction (SPE) followed by capillary electrophoresis (CE) analysis. The method is accurate, reproducible, sensitive, relatively safe, and easy to perform, and avoids the use of large amounts of solvent for liquid-liquid extraction and the potential hazards and hassles of derivatization. The cost of analyzing HAAs using this method should be lower than the currently approved methods, and utilities with a GC/ECD can perform the analysis in-house.

Rapid B-rep model preprocessing for immersogeometric analysis using analytic surfaces

PubMed Central

Wang, Chenglong; Xu, Fei; Hsu, Ming-Chen; Krishnamurthy, Adarsh

2017-01-01

Computational fluid dynamics (CFD) simulations of flow over complex objects have been performed traditionally using fluid-domain meshes that conform to the shape of the object. However, creating shape conforming meshes for complicated geometries like automobiles require extensive geometry preprocessing. This process is usually tedious and requires modifying the geometry, including specialized operations such as defeaturing and filling of small gaps. Hsu et al. (2016) developed a novel immersogeometric fluid-flow method that does not require the generation of a boundary-fitted mesh for the fluid domain. However, their method used the NURBS parameterization of the surfaces for generating the surface quadrature points to enforce the boundary conditions, which required the B-rep model to be converted completely to NURBS before analysis can be performed. This conversion usually leads to poorly parameterized NURBS surfaces and can lead to poorly trimmed or missing surface features. In addition, converting simple geometries such as cylinders to NURBS imposes a performance penalty since these geometries have to be dealt with as rational splines. As a result, the geometry has to be inspected again after conversion to ensure analysis compatibility and can increase the computational cost. In this work, we have extended the immersogeometric method to generate surface quadrature points directly using analytic surfaces. We have developed quadrature rules for all four kinds of analytic surfaces: planes, cones, spheres, and toroids. We have also developed methods for performing adaptive quadrature on trimmed analytic surfaces. Since analytic surfaces have frequently been used for constructing solid models, this method is also faster to generate quadrature points on real-world geometries than using only NURBS surfaces. To assess the accuracy of the proposed method, we perform simulations of a benchmark problem of flow over a torpedo shape made of analytic surfaces and compare those to immersogeometric simulations of the same model with NURBS surfaces. We also compare the results of our immersogeometric method with those obtained using boundary-fitted CFD of a tessellated torpedo shape, and quantities of interest such as drag coefficient are in good agreement. Finally, we demonstrate the effectiveness of our immersogeometric method for high-fidelity industrial scale simulations by performing an aerodynamic analysis of a truck that has a large percentage of analytic surfaces. Using analytic surfaces over NURBS avoids unnecessary surface type conversion and significantly reduces model-preprocessing time, while providing the same accuracy for the aerodynamic quantities of interest. PMID:29051678

CameraHRV: robust measurement of heart rate variability using a camera

NASA Astrophysics Data System (ADS)

Pai, Amruta; Veeraraghavan, Ashok; Sabharwal, Ashutosh

2018-02-01

The inter-beat-interval (time period of the cardiac cycle) changes slightly for every heartbeat; this variation is measured as Heart Rate Variability (HRV). HRV is presumed to occur due to interactions between the parasym- pathetic and sympathetic nervous system. Therefore, it is sometimes used as an indicator of the stress level of an individual. HRV also reveals some clinical information about cardiac health. Currently, HRV is accurately measured using contact devices such as a pulse oximeter. However, recent research in the field of non-contact imaging Photoplethysmography (iPPG) has made vital sign measurements using just the video recording of any exposed skin (such as a person's face) possible. The current signal processing methods for extracting HRV using peak detection perform well for contact-based systems but have poor performance for the iPPG signals. The main reason for this poor performance is the fact that current methods are sensitive to large noise sources which are often present in iPPG data. Further, current methods are not robust to motion artifacts that are common in iPPG systems. We developed a new algorithm, CameraHRV, for robustly extracting HRV even in low SNR such as is common with iPPG recordings. CameraHRV combined spatial combination and frequency demodulation to obtain HRV from the instantaneous frequency of the iPPG signal. CameraHRV outperforms other current methods of HRV estimation. Ground truth data was obtained from FDA-approved pulse oximeter for validation purposes. CameraHRV on iPPG data showed an error of 6 milliseconds for low motion and varying skin tone scenarios. The improvement in error was 14%. In case of high motion scenarios like reading, watching and talking, the error was 10 milliseconds.

Organizational Failure in an NHS Hospital Trust: A Qualitative Study.

PubMed

Ravaghi, Hamid; Mannion, Russell; Sajadi, Haniye Sadat

2015-01-01

The objective was to explore the key factors associated with organizational failure in an NHS Hospital Trust. This case study adopted a qualitative design. Fifty-seven semistructured interviews and document analyses were conducted as well. Data were analyzed using a framework analysis method. A range of symptoms of organizational performance failure was identified. These relate to a financial deficit, lack of good external relationships, inability to meet core targets, a lack of clear management systems, and low staff morale. These markers had not been taken seriously by the previous senior management team. Symptoms of failure were the reflection of presence of secondary and primary causes of failure. Poor managerial leadership, poor financial control and performance management, lack of open culture, distraction by 2 large projects, and the lack of clinician engagement were perceived as internal causes of failure and the high level of policy changes within the NHS as the key external cause. The level of deprivation in the area was also thought to have had a negative impact on performance. The findings reinforce and expand on those of recent studies across the public sector. Tracking an organization's performance and early diagnosis of performance problems, focusing on performance management systems, and taking into account contextual factors are issues that should be considered.

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

Kubicek, Gregory J., E-mail: kubicek-gregory@cooperhealth.edu; Turtz, Alan; Xue, Jinyu

Purpose: Patients with poor performance status (PS), usually defined as a Karnofsky Performance Status of 60 or less, were not eligible for randomized stereotactic radiosurgery (SRS) studies, and many guidelines suggest that whole-brain radiation therapy (WBRT) is the most appropriate treatment for poor PS patients. Methods and Materials: In this retrospective review of our SRS database, we identified 36 patients with PS of 60 or less treated with SRS for central nervous system (CNS) metastatic disease. PS, as defined by the Karnofsky Performance Status, was 60 (27 patients), 50 (8 patients), or 40 (1 patient). The median number of CNSmore » lesions treated was 3. Results: Median overall survival (OS) was 7.2 months (range, 0.73-25.6 months). Fifteen patients (41%) were alive at 6 months, and 6 patients (16.6%) were alive at 1 year. There was no difference in OS in patients who underwent previous WBRT. There were no local failures or cases of radiation toxicity. Distant CNS failures were seen in 9 patients (25%). Conclusions: Our patients with poor PS had reasonable median OS and relatively low distant CNS failure rates. Patients in this patient population may be ideal candidates for SRS compared with WBRT given the low incidence of distant failure over their remaining lives and the favorable logistics of single-fraction treatment for these patients with debility and their caregivers.« less

Improving Students' Understanding and Perception of Cell Theory in School Biology Using a Computer-Based Instruction Simulation Program

ERIC Educational Resources Information Center

Kiboss, Joel; Wekesa, Eric; Ndirangu, Mwangi

2006-01-01

A survey by the Kenya National Examination Council (KNEC) revealed that students' academic performance and interest in secondary school biology has been generally poor. This has been attributed to the current methods of instruction and the lack of instructional resources amenable to the study and proper understanding of such complex areas as cell…

Effects of Advance Organiser Strategy during Instruction on Secondary School Students' Mathematics Achievement in Kenya's Nakuru District

ERIC Educational Resources Information Center

Githua, Bernard N.; Nyabwa, Rachel Angela

2008-01-01

Students have continued to perform poorly in KCSE examinations in certain mathematics topics taught in secondary schools in Kenya. One such topic is commercial arithmetic. Successful teaching of mathematics depends partly on correct use of teaching methods in classroom settings. This study sought to examine how the use of advance organisers during…

Risk for Poor Performance on a Language Screening Measure for Bilingual Preschoolers and Kindergarteners

ERIC Educational Resources Information Center

Pena, Elizabeth D.; Gillam, Ronald B.; Bedore, Lisa M.; Bohman, Thomas M.

2011-01-01

Purpose: This study documents the risk for language impairment in Latino children who had different levels of exposure to English and Spanish. Method: A total of 1,029 preschool- and kindergarten-age children were screened in the domains of semantics and morphosyntax in both Spanish and English. Parent report was used to document current exposure…

Nicaraguan Sign Language and Theory of Mind: The Issue of Critical Periods and Abilities

ERIC Educational Resources Information Center

Morgan, Gary; Kegl, Judy

2006-01-01

Background: Previous studies in the literature report that deaf individuals who experience late access to language perform poorly on false belief tests of Theory of Mind (ToM) compared with age-matched deaf and hearing controls exposed to language early. Methods: A group of 22 deaf Nicaraguans (aged 7 to 39 years) who learned Nicaraguan Sign…

76 FR 18534 - Pacific Fishery Management Council; Public Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-04

.... SUMMARY: The review panel (Panel) for assessment methods for data-poor species will hold a work session that is open to the public. DATES: The Review of Assessment Methods for Data-Poor Species will be held... Panel will adjourn on Friday, April 29, 2011. ADDRESSES: The Review of Assessment Methods for Data-Poor...

Oxygen influencing the photocarriers lifetime of CH3NH3PbI3-xClx film grown by two-step interdiffusion method and its photovoltaic performance

NASA Astrophysics Data System (ADS)

Yuan, Shuai; Qiu, Zhiwen; Zhang, Hailiang; Gong, Haibo; Hao, Yufeng; Cao, Bingqiang

2016-01-01

During the growth of CH3NH3PbI3-xClx (MAPbI3-xClx) perovskite films by the two-step inter-diffusion method, the presence of a trace amount of oxygen gas is critical to their physical properties and photovoltaic performance. As the oxygen concentration increases, poor film morphologies and incomplete surface coverage are observed. Moreover, by XRD, Raman scattering, and photoluminescence measurements, we find that MAPbI3-xClx grains become more distorted and the electron-hole recombination rate dramatically increases. Higher oxygen concentration triggers a sharp decrease in the current density and the fill factor of corresponding solar cells, which degrades device performance, on average, from 14.3% to 4.4%. This work proves the importance of controlling the oxygen atmosphere in the fabrication of high-performance perovskite solar cells.

Lower-limb kinematics of single-leg squat performance in young adults.

PubMed

Horan, Sean A; Watson, Steven L; Carty, Christopher P; Sartori, Massimo; Weeks, Benjamin K

2014-01-01

To determine the kinematic parameters that characterize good and poor single-leg squat (SLS) performance. A total of 22 healthy young adults free from musculoskeletal impairment were recruited for testing. For each SLS, both two-dimensional video and three-dimensional motion analysis data were collected. Pelvis, hip, and knee angles were calculated using a reliable and validated lower-limb (LL) biomechanical model. Two-dimensional video clips of SLSs were blindly assessed in random order by eight musculoskeletal physiotherapists using a 10-point ordinal scale. To facilitate between-group comparisons, SLS performances were stratified by tertiles corresponding to poor, intermediate, and good SLS performance. Mean ratings of SLS performance assessed by physiotherapists were 8.3 (SD 0.5), 6.8 (SD 0.7), and 4.0 (SD 0.8) for good, intermediate, and poor squats, respectively. Three-dimensional analysis revealed that people whose SLS performance was assessed as poor exhibited increased hip adduction, reduced knee flexion, and increased medio-lateral displacement of the knee joint centre compared to those whose SLS performance was assessed as good (p≤0.05). Overall, poor SLS performance is characterized by inadequate knee flexion and excessive frontal plane motion of the knee and hip. Future investigations of SLS performance should consider standardizing knee flexion angle to illuminate other influential kinematic parameters.

Doctors' stress responses and poor communication performance in simulated bad-news consultations.

PubMed

Brown, Rhonda; Dunn, Stewart; Byrnes, Karen; Morris, Richard; Heinrich, Paul; Shaw, Joanne

2009-11-01

No studies have previously evaluated factors associated with high stress levels and poor communication performance in breaking bad news (BBN) consultations. This study determined factors that were most strongly related to doctors' stress responses and poor communication performance during a simulated BBN task. In 2007, the authors recruited 24 doctors comprising 12 novices (i.e., interns/residents with 1-3 years' experience) and 12 experts (i.e., registrars, medical/radiation oncologists, or cancer surgeons, with more than 4 years' experience). Doctors participated in simulated BBN consultations and a number of control tasks. Five-minute-epoch heart rate (HR), HR variability, and communication performance were assessed in all participants. Subjects also completed a short questionnaire asking about their prior experience BBN, perceived stress, psychological distress (i.e., anxiety, depression), fatigue, and burnout. High stress responses were related to inexperience with BBN, fatigue, and giving bad versus good news. Poor communication performance in the consultation was related to high burnout and fatigue scores. These results suggest that BBN was a stressful experience for doctors even in a simulated encounter, especially for those who were inexperienced and/or fatigued. Poor communication performance was related to burnout and fatigue, but not inexperience with BBN. These results likely indicate that burnout and fatigue contributed to stress and poor work performance in some doctors during the simulated BBN task.

[Attrition and poor performance in general practice training: age, competence and knowledge play a role].

PubMed

Vermeulen, Margit I; Kuyvenhoven, Marijke M; Zuithoff, N P A Peter; van der Graaf, Yolanda; Pieters, H M Ron

2011-01-01

To investigate which determinants are related to poor performance and forced attrition in the first year residency in general practice (GP). Observational retrospective cohort study. We collected data relating to personal characteristics such as age, sex and clinical experience from residents who started the GP training in Utrecht, the Netherlands, in the period March 2005-August 2007. We also collected competence scores from the domains 'medical expertise', 'doctor-patient communication' and 'professionalism', as well as scores on a national GP knowledge test. The outcome measures were 'poor performance' and 'forced attrition'. Multivariate logistic regression was used to analyse correlations between personal characteristics, competence scores on the 3 domains and knowledge scores in the first trimester on the one hand and poor performance or forced attrition on the other. 215 residents started the GP training. In the first trimester a quarter of the residents had an insufficient score in 1 or more of the domains. Competence scores were mutually correlated, but did not correlate with the knowledge score. 18 residents showed poor performance and 3 were forced to stop their training. Poor performance and forced attrition were correlated with age (adjusted odds ratio (OR): 1.1; 95% CI: 1.0-1.3), insufficient knowledge (adjusted OR: 8.9; 3.0-26.3) and medical expertise (adjusted OR: 2.1; 1.1-4.0) at the beginning of the training. Age, insufficient knowledge of general practice, and insufficient competence in the domain of 'medical expertise' at the beginning of the training are risk factors for poor performance by residents and attrition from their GP training.

Analysis of free modeling predictions by RBO aleph in CASP11.

PubMed

Mabrouk, Mahmoud; Werner, Tim; Schneider, Michael; Putz, Ines; Brock, Oliver

2016-09-01

The CASP experiment is a biannual benchmark for assessing protein structure prediction methods. In CASP11, RBO Aleph ranked as one of the top-performing automated servers in the free modeling category. This category consists of targets for which structural templates are not easily retrievable. We analyze the performance of RBO Aleph and show that its success in CASP was a result of its ab initio structure prediction protocol. A detailed analysis of this protocol demonstrates that two components unique to our method greatly contributed to prediction quality: residue-residue contact prediction by EPC-map and contact-guided conformational space search by model-based search (MBS). Interestingly, our analysis also points to a possible fundamental problem in evaluating the performance of protein structure prediction methods: Improvements in components of the method do not necessarily lead to improvements of the entire method. This points to the fact that these components interact in ways that are poorly understood. This problem, if indeed true, represents a significant obstacle to community-wide progress. Proteins 2016; 84(Suppl 1):87-104. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Performance Metrics for Monitoring Parallel Program Executions

NASA Technical Reports Server (NTRS)

Sarukkai, Sekkar R.; Gotwais, Jacob K.; Yan, Jerry; Lum, Henry, Jr. (Technical Monitor)

1994-01-01

Existing tools for debugging performance of parallel programs either provide graphical representations of program execution or profiles of program executions. However, for performance debugging tools to be useful, such information has to be augmented with information that highlights the cause of poor program performance. Identifying the cause of poor performance necessitates the need for not only determining the significance of various performance problems on the execution time of the program, but also needs to consider the effect of interprocessor communications of individual source level data structures. In this paper, we present a suite of normalized indices which provide a convenient mechanism for focusing on a region of code with poor performance and highlights the cause of the problem in terms of processors, procedures and data structure interactions. All the indices are generated from trace files augmented with data structure information.. Further, we show with the help of examples from the NAS benchmark suite that the indices help in detecting potential cause of poor performance, based on augmented execution traces obtained by monitoring the program.

Isotonic Regression Based-Method in Quantitative High-Throughput Screenings for Genotoxicity

PubMed Central

Fujii, Yosuke; Narita, Takeo; Tice, Raymond Richard; Takeda, Shunich

2015-01-01

Quantitative high-throughput screenings (qHTSs) for genotoxicity are conducted as part of comprehensive toxicology screening projects. The most widely used method is to compare the dose-response data of a wild-type and DNA repair gene knockout mutants, using model-fitting to the Hill equation (HE). However, this method performs poorly when the observed viability does not fit the equation well, as frequently happens in qHTS. More capable methods must be developed for qHTS where large data variations are unavoidable. In this study, we applied an isotonic regression (IR) method and compared its performance with HE under multiple data conditions. When dose-response data were suitable to draw HE curves with upper and lower asymptotes and experimental random errors were small, HE was better than IR, but when random errors were big, there was no difference between HE and IR. However, when the drawn curves did not have two asymptotes, IR showed better performance (p < 0.05, exact paired Wilcoxon test) with higher specificity (65% in HE vs. 96% in IR). In summary, IR performed similarly to HE when dose-response data were optimal, whereas IR clearly performed better in suboptimal conditions. These findings indicate that IR would be useful in qHTS for comparing dose-response data. PMID:26673567

[Abdominal ultrasound and magnetic resonance imaging: a comparative study on the non-alcoholic fatty liver disease diagnosis in morbidly obese patients].

PubMed

Chaves, Gabriela Villaça; Pereira, Sílvia Elaine; Saboya, Carlos José; Cortes, Caroline; Ramalho, Rejane

2009-01-01

To evaluate the concordance between abdominal ultrasound and an MRI (Magnetic Resonance Imaging) in the diagnosis of non-alcoholic fatty liver disease (NAFLD), and concordance of these two methods with the histopathological exam. The population studied was comprised of 145 patients with morbid obesity (BMI > or = 40 Kg/m(2)), of both genders. NAFLD diagnosis was performed by MRI and Ultrasound. Liver biopsy was performed in a sub-sample (n=40). To evaluate the concordance of these two methods, the kappa coefficient was used. Concordance between both methods (MRI and Ultrasound) was poor and not significant (Kappa adjusted= 0.27; CI 95%= 0.07-0.39.) Nevertheless a slight concordance was found between diagnosis of NAFLD by ultrasound and the hepatic biopsy, with 83.,3% of concordant results and Kappa adjusted= 0.67.Results of an MRI and the histopathological exam were compared and results showed 53.6% of concordant results and kappa adjusted= 0.07. The concordance found in the diagnosis performed using the ultrasound method and the hepatic biopsy, shows a need to implement and perform more research on the use of ultrasound to validate and reconsider these methods. This would minimize the need to perform biopsies to detect and diagnose such disease.

Body Adiposity Index Performance in Estimating Body Fat Percentage in Colombian College Students: Findings from the FUPRECOL—Adults Study

PubMed Central

Ramírez-Vélez, Robinson; Correa-Bautista, Jorge Enrique; González-Ruíz, Katherine; Vivas, Andrés; Triana-Reina, Héctor Reynaldo; Martínez-Torres, Javier; Prieto-Benavides, Daniel Humberto; Carrillo, Hugo Alejandro; Ramos-Sepúlveda, Jeison Alexander; Villa-González, Emilio; García-Hermoso, Antonio

2017-01-01

Recently, a body adiposity index (BAI = (hip circumference)/((height)(1.5))−18) was developed and validated in adult populations. The aim of this study was to evaluate the performance of BAI in estimating percentage body fat (BF%) in a sample of Colombian collegiate young adults. The participants were comprised of 903 volunteers (52% females, mean age = 21.4 years ± 3.3). We used the Lin’s concordance correlation coefficient, linear regression, Bland–Altman’s agreement analysis, concordance correlation coefficient (ρc) and the coefficient of determination (R2) between BAI, and BF%; by bioelectrical impedance analysis (BIA)). The correlation between the two methods of estimating BF% was R2 = 0.384, p < 0.001. A paired-sample t-test showed a difference between the methods (BIA BF% = 16.2 ± 3.1, BAI BF% = 30.0 ± 5.4%; p < 0.001). For BIA, bias value was 6.0 ± 6.2 BF% (95% confidence interval (CI) = −6.0 to 18.2), indicating that the BAI method overestimated BF% relative to the reference method. Lin’s concordance correlation coefficient was poor (ρc = 0.014, 95% CI = −0.124 to 0.135; p = 0.414). In Colombian college students, there was poor agreement between BAI- and BIA-based estimates of BF%, and so BAI is not accurate in people with low or high body fat percentage levels. PMID:28106719

Sleep Quality Prediction From Wearable Data Using Deep Learning

PubMed Central

Sathyanarayana, Aarti; Joty, Shafiq; Ofli, Ferda; Srivastava, Jaideep; Elmagarmid, Ahmed; Arora, Teresa; Taheri, Shahrad

2016-01-01

Background The importance of sleep is paramount to health. Insufficient sleep can reduce physical, emotional, and mental well-being and can lead to a multitude of health complications among people with chronic conditions. Physical activity and sleep are highly interrelated health behaviors. Our physical activity during the day (ie, awake time) influences our quality of sleep, and vice versa. The current popularity of wearables for tracking physical activity and sleep, including actigraphy devices, can foster the development of new advanced data analytics. This can help to develop new electronic health (eHealth) applications and provide more insights into sleep science. Objective The objective of this study was to evaluate the feasibility of predicting sleep quality (ie, poor or adequate sleep efficiency) given the physical activity wearable data during awake time. In this study, we focused on predicting good or poor sleep efficiency as an indicator of sleep quality. Methods Actigraphy sensors are wearable medical devices used to study sleep and physical activity patterns. The dataset used in our experiments contained the complete actigraphy data from a subset of 92 adolescents over 1 full week. Physical activity data during awake time was used to create predictive models for sleep quality, in particular, poor or good sleep efficiency. The physical activity data from sleep time was used for the evaluation. We compared the predictive performance of traditional logistic regression with more advanced deep learning methods: multilayer perceptron (MLP), convolutional neural network (CNN), simple Elman-type recurrent neural network (RNN), long short-term memory (LSTM-RNN), and a time-batched version of LSTM-RNN (TB-LSTM). Results Deep learning models were able to predict the quality of sleep (ie, poor or good sleep efficiency) based on wearable data from awake periods. More specifically, the deep learning methods performed better than traditional linear regression. CNN had the highest specificity and sensitivity, and an overall area under the receiver operating characteristic (ROC) curve (AUC) of 0.9449, which was 46% better as compared with traditional linear regression (0.6463). Conclusions Deep learning methods can predict the quality of sleep based on actigraphy data from awake periods. These predictive models can be an important tool for sleep research and to improve eHealth solutions for sleep. PMID:27815231

Computational Methods for Configurational Entropy Using Internal and Cartesian Coordinates.

PubMed

Hikiri, Simon; Yoshidome, Takashi; Ikeguchi, Mitsunori

2016-12-13

The configurational entropy of solute molecules is a crucially important quantity to study various biophysical processes. Consequently, it is necessary to establish an efficient quantitative computational method to calculate configurational entropy as accurately as possible. In the present paper, we investigate the quantitative performance of the quasi-harmonic and related computational methods, including widely used methods implemented in popular molecular dynamics (MD) software packages, compared with the Clausius method, which is capable of accurately computing the change of the configurational entropy upon temperature change. Notably, we focused on the choice of the coordinate systems (i.e., internal or Cartesian coordinates). The Boltzmann-quasi-harmonic (BQH) method using internal coordinates outperformed all the six methods examined here. The introduction of improper torsions in the BQH method improves its performance, and anharmonicity of proper torsions in proteins is identified to be the origin of the superior performance of the BQH method. In contrast, widely used methods implemented in MD packages show rather poor performance. In addition, the enhanced sampling of replica-exchange MD simulations was found to be efficient for the convergent behavior of entropy calculations. Also in folding/unfolding transitions of a small protein, Chignolin, the BQH method was reasonably accurate. However, the independent term without the correlation term in the BQH method was most accurate for the folding entropy among the methods considered in this study, because the QH approximation of the correlation term in the BQH method was no longer valid for the divergent unfolded structures.

Image quality classification for DR screening using deep learning.

PubMed

FengLi Yu; Jing Sun; Annan Li; Jun Cheng; Cheng Wan; Jiang Liu

2017-07-01

The quality of input images significantly affects the outcome of automated diabetic retinopathy (DR) screening systems. Unlike the previous methods that only consider simple low-level features such as hand-crafted geometric and structural features, in this paper we propose a novel method for retinal image quality classification (IQC) that performs computational algorithms imitating the working of the human visual system. The proposed algorithm combines unsupervised features from saliency map and supervised features coming from convolutional neural networks (CNN), which are fed to an SVM to automatically detect high quality vs poor quality retinal fundus images. We demonstrate the superior performance of our proposed algorithm on a large retinal fundus image dataset and the method could achieve higher accuracy than other methods. Although retinal images are used in this study, the methodology is applicable to the image quality assessment and enhancement of other types of medical images.

Redundancy analysis allows improved detection of methylation changes in large genomic regions.

PubMed

Ruiz-Arenas, Carlos; González, Juan R

2017-12-14

DNA methylation is an epigenetic process that regulates gene expression. Methylation can be modified by environmental exposures and changes in the methylation patterns have been associated with diseases. Methylation microarrays measure methylation levels at more than 450,000 CpGs in a single experiment, and the most common analysis strategy is to perform a single probe analysis to find methylation probes associated with the outcome of interest. However, methylation changes usually occur at the regional level: for example, genomic structural variants can affect methylation patterns in regions up to several megabases in length. Existing DMR methods provide lists of Differentially Methylated Regions (DMRs) of up to only few kilobases in length, and cannot check if a target region is differentially methylated. Therefore, these methods are not suitable to evaluate methylation changes in large regions. To address these limitations, we developed a new DMR approach based on redundancy analysis (RDA) that assesses whether a target region is differentially methylated. Using simulated and real datasets, we compared our approach to three common DMR detection methods (Bumphunter, blockFinder, and DMRcate). We found that Bumphunter underestimated methylation changes and blockFinder showed poor performance. DMRcate showed poor power in the simulated datasets and low specificity in the real data analysis. Our method showed very high performance in all simulation settings, even with small sample sizes and subtle methylation changes, while controlling type I error. Other advantages of our method are: 1) it estimates the degree of association between the DMR and the outcome; 2) it can analyze a targeted or region of interest; and 3) it can evaluate the simultaneous effects of different variables. The proposed methodology is implemented in MEAL, a Bioconductor package designed to facilitate the analysis of methylation data. We propose a multivariate approach to decipher whether an outcome of interest alters the methylation pattern of a region of interest. The method is designed to analyze large target genomic regions and outperforms the three most popular methods for detecting DMRs. Our method can evaluate factors with more than two levels or the simultaneous effect of more than one continuous variable, which is not possible with the state-of-the-art methods.

Segmentation of real-time three-dimensional ultrasound for quantification of ventricular function: a clinical study on right and left ventricles.

PubMed

Angelini, Elsa D; Homma, Shunichi; Pearson, Gregory; Holmes, Jeffrey W; Laine, Andrew F

2005-09-01

Among screening modalities, echocardiography is the fastest, least expensive and least invasive method for imaging the heart. A new generation of three-dimensional (3-D) ultrasound (US) technology has been developed with real-time 3-D (RT3-D) matrix phased-array transducers. These transducers allow interactive 3-D visualization of cardiac anatomy and fast ventricular volume estimation without tomographic interpolation as required with earlier 3-D US acquisition systems. However, real-time acquisition speed is performed at the cost of decreasing spatial resolution, leading to echocardiographic data with poor definition of anatomical structures and high levels of speckle noise. The poor quality of the US signal has limited the acceptance of RT3-D US technology in clinical practice, despite the wealth of information acquired by this system, far greater than with any other existing echocardiography screening modality. We present, in this work, a clinical study for segmentation of right and left ventricular volumes using RT3-D US. A preprocessing of the volumetric data sets was performed using spatiotemporal brushlet denoising, as presented in previous articles Two deformable-model segmentation methods were implemented in 2-D using a parametric formulation and in 3-D using an implicit formulation with a level set implementation for extraction of endocardial surfaces on denoised RT3-D US data. A complete and rigorous validation of the segmentation methods was carried out for quantification of left and right ventricular volumes and ejection fraction, including comparison of measurements with cardiac magnetic resonance imaging as the reference. Results for volume and ejection fraction measurements report good performance of quantification of cardiac function on RT3-D data compared with magnetic resonance imaging with better performance of semiautomatic segmentation methods than with manual tracing on the US data.

Twin Screw Extruder Production of MTTP Decoy Flares SERDP WP-1240

DTIC Science & Technology

2005-12-01

5 3. Carnauba Wax ( wax from palm tree exudate, a common ingredient in high quality car polish) Hazards of the remaining formulations were...1. Microsere 5866, a microcrystalline wax derived from refining petroleum 2. Elvax 250, poly(ethylene-co-vinyl acetate) (hot glue ingredient...5866 Poor performance when 1-gm sample ignited Elvax 250 Poor performance when 1-gm sample ignited Carnuba Wax Poor performance when 1-gm sample

THE SYNTHETIC-OVERSAMPLING METHOD: USING PHOTOMETRIC COLORS TO DISCOVER EXTREMELY METAL-POOR STARS

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

Miller, A. A., E-mail: amiller@astro.caltech.edu

2015-09-20

Extremely metal-poor (EMP) stars ([Fe/H] ≤ −3.0 dex) provide a unique window into understanding the first generation of stars and early chemical enrichment of the universe. EMP stars are exceptionally rare, however, and the relatively small number of confirmed discoveries limits our ability to exploit these near-field probes of the first ∼500 Myr after the Big Bang. Here, a new method to photometrically estimate [Fe/H] from only broadband photometric colors is presented. I show that the method, which utilizes machine-learning algorithms and a training set of ∼170,000 stars with spectroscopically measured [Fe/H], produces a typical scatter of ∼0.29 dex. Thismore » performance is similar to what is achievable via low-resolution spectroscopy, and outperforms other photometric techniques, while also being more general. I further show that a slight alteration to the model, wherein synthetic EMP stars are added to the training set, yields the robust identification of EMP candidates. In particular, this synthetic-oversampling method recovers ∼20% of the EMP stars in the training set, at a precision of ∼0.05. Furthermore, ∼65% of the false positives from the model are very metal-poor stars ([Fe/H] ≤ −2.0 dex). The synthetic-oversampling method is biased toward the discovery of warm (∼F-type) stars, a consequence of the targeting bias from the Sloan Digital Sky Survey/Sloan Extension for Galactic Understanding survey. This EMP selection method represents a significant improvement over alternative broadband optical selection techniques. The models are applied to >12 million stars, with an expected yield of ∼600 new EMP stars, which promises to open new avenues for exploring the early universe.« less

Validation of a simple method for predicting the disinfection performance in a flow-through contactor.

PubMed

Pfeiffer, Valentin; Barbeau, Benoit

2014-02-01

Despite its shortcomings, the T10 method introduced by the United States Environmental Protection Agency (USEPA) in 1989 is currently the method most frequently used in North America to calculate disinfection performance. Other methods (e.g., the Integrated Disinfection Design Framework, IDDF) have been advanced as replacements, and more recently, the USEPA suggested the Extended T10 and Extended CSTR (Continuous Stirred-Tank Reactor) methods to improve the inactivation calculations within ozone contactors. To develop a method that fully considers the hydraulic behavior of the contactor, two models (Plug Flow with Dispersion and N-CSTR) were successfully fitted with five tracer tests results derived from four Water Treatment Plants and a pilot-scale contactor. A new method based on the N-CSTR model was defined as the Partially Segregated (Pseg) method. The predictions from all the methods mentioned were compared under conditions of poor and good hydraulic performance, low and high disinfectant decay, and different levels of inactivation. These methods were also compared with experimental results from a chlorine pilot-scale contactor used for Escherichia coli inactivation. The T10 and Extended T10 methods led to large over- and under-estimations. The Segregated Flow Analysis (used in the IDDF) also considerably overestimated the inactivation under high disinfectant decay. Only the Extended CSTR and Pseg methods produced realistic and conservative predictions in all cases. Finally, a simple implementation procedure of the Pseg method was suggested for calculation of disinfection performance. Copyright © 2013 Elsevier Ltd. All rights reserved.

Substance Use as a Strong Predictor of Poor Academic Achievement among University Students

PubMed Central

Fekadu, Wubalem; Mekonnen, Tefera Chane; Workie, Shimelash Bitew

2017-01-01

Background Substance use is a growing concern globally and its association with students' academic performance is not well studied. Objective This study was aimed to assess the prevalence of substance use (alcohol, tobacco, and khat) and its association with academic performance among university students. Methods Cross-sectional study was conducted among Wolaita Sodo University students. A total of 747 students were selected by using cluster sampling technique. Data were collected by pretested self-administered questionnaire and examined using descriptive statistics and linear regression with 95% confidence intervals. Variables with p value of less than 0.05 were considered as statistically significant. Result Prevalence of substance use (alcohol, tobacco, and khat) was 28.6%. Substance use (current smoking, chewing khat at least weekly, drinking alcohol on a daily basis, and having intimate friend who uses substance) was significantly and negatively associated with students' academic performance. Conclusion Substance use among Wolaita Sodo University students was as common as other studies in Sub-Saharan countries and negatively associated with students' academic achievement. The common practice of substance use and its association with poor academic performance demand the universities to have a good control of substance and to implement youth friendly activities. PMID:28680879

Evidence that communication impairment in schizophrenia is associated with generalized poor task performance.

PubMed

Merrill, Anne M; Karcher, Nicole R; Cicero, David C; Becker, Theresa M; Docherty, Anna R; Kerns, John G

2017-03-01

People with schizophrenia exhibit wide-ranging cognitive deficits, including slower processing speed and decreased cognitive control. Disorganized speech symptoms, such as communication impairment, have been associated with poor cognitive control task performance (e.g., goal maintenance and working memory). Whether communication impairment is associated with poorer performance on a broader range of non-cognitive control measures is unclear. In the current study, people with schizophrenia (n =51) and non-psychiatric controls (n =26) completed speech interviews allowing for reliable quantitative assessment of communication impairment. Participants also completed multiple goal maintenance and working memory tasks. In addition, we also examined (a) simple measures of processing speed involving highly automatic prepotent responses and (b) a non-cognitive control measure of general task performance. Schizophrenia communication impairment was significantly associated with poor performance in all cognitive domains, with the largest association found with processing speed (r s =-0.52). Further, communication impairment was also associated with the non-cognitive control measure of poor general task performance (r s =-0.43). In contrast, alogia, a negative speech symptom, and positive symptoms were less if at all related to cognitive task performance. Overall, this study suggests that communication impairment in schizophrenia may be associated with relatively generalized poor cognitive task performance. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Is Toxoplasma Gondii Infection Related to Brain and Behavior Impairments in Humans? Evidence from a Population-Representative Birth Cohort

PubMed Central

Sugden, Karen; Moffitt, Terrie E.; Pinto, Lauriane; Poulton, Richie; Williams, Benjamin S.; Caspi, Avshalom

2016-01-01

Background Toxoplasma gondii (T. gondii) is a protozoan parasite present in around a third of the human population. Infected individuals are commonly asymptomatic, though recent reports have suggested that infection might influence aspects of the host’s behavior. In particular, Toxoplasma infection has been linked to schizophrenia, suicide attempt, differences in aspects of personality and poorer neurocognitive performance. However, these studies are often conducted in clinical samples or convenience samples. Methods/Results In a population-representative birth-cohort of individuals tested for presence of antibodies to T. gondii (N = 837) we investigated the association between infection and four facets of human behavior: neuropsychiatric disorder (schizophrenia and major depression), poor impulse control (suicidal behavior and criminality), personality, and neurocognitive performance. Suicide attempt was marginally more frequent among individuals with T. gondii seropositivity (p = .06). Seropositive individuals also performed worse on one out of 14 measures of neuropsychological function. Conclusion On the whole, there was little evidence that T. gondii was related to increased risk of psychiatric disorder, poor impulse control, personality aberrations or neurocognitive impairment. PMID:26886853

Activation of the STAT3 Signaling Pathway Is Associated With Poor Survival in Diffuse Large B-Cell Lymphoma Treated With R-CHOP

PubMed Central

Huang, Xin; Meng, Bin; Iqbal, Javeed; Ding, B. Belinda; Perry, Anamarija M.; Cao, Wenfeng; Smith, Lynette M.; Bi, Chengfeng; Jiang, Chunsun; Greiner, Timothy C.; Weisenburger, Dennis D.; Rimsza, Lisa; Rosenwald, Andreas; Ott, German; Delabie, Jan; Campo, Elias; Braziel, Rita M.; Gascoyne, Randy D.; Cook, James R.; Tubbs, Raymond R.; Jaffe, Elaine S.; Armitage, James O.; Vose, Julie M.; Staudt, Louis M.; McKeithan, Timothy W.; Chan, Wing C.; Ye, B. Hilda; Fu, Kai

2013-01-01

Purpose We previously reported that constitutive STAT3 activation is a prominent feature of the activated B-cell subtype of diffuse large B-cell lymphomas (ABC-DLBCL). In this study, we investigated whether STAT3 activation can risk stratify patients with DLBCL. Patients and Methods By an immunohistochemical method, we investigated phosphotyrosine STAT3 (PY-STAT3) expression from 185 patients with DLBCL treated with R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone). Cell line-based siRNA experiments were also performed to generate an 11-gene, PY-STAT3 activation signature, which was used to study a previously published cohort of 222 patients with DLBCL. The STAT3 activation status determined by these two methods and by STAT3 mRNA levels were then correlated with survival. Results PY-STAT3 was detected in 37% of DLBCL and enriched in ABC-DLBCL cases (P = .03). PY-STAT3 positivity significantly correlated with poor overall survival (OS; P = .01) and event-free survival (EFS; P = .006). Similar observations were made for high levels of STAT3 mRNA. In multivariable analysis, PY-STAT3 status (P = .02), International Prognostic Index (P = .02), and BCL2 expression (P = .046) were independent prognosticators of OS in this cohort. Among the cell-of-origin subgroups, PY-STAT3 was associated with poor EFS among non–germinal center B-cell DLBCL cases only (P = .027). Similarly, the 11-gene STAT3 activation signature correlated with poor survival in the entire DLBCL cohort (OS, P < .001; EFS, P < .001) as well as the ABC-DLBCL subgroup (OS, P = .029; EFS, P = .025). Conclusion STAT3 activation correlated with poor survival in patients with DLBCL treated with R-CHOP, especially those with tumors of the ABC-DLBCL subtype. PMID:24220563

Delineating Species with DNA Barcodes: A Case of Taxon Dependent Method Performance in Moths

PubMed Central

Kekkonen, Mari; Mutanen, Marko; Kaila, Lauri; Nieminen, Marko; Hebert, Paul D. N.

2015-01-01

The accelerating loss of biodiversity has created a need for more effective ways to discover species. Novel algorithmic approaches for analyzing sequence data combined with rapidly expanding DNA barcode libraries provide a potential solution. While several analytical methods are available for the delineation of operational taxonomic units (OTUs), few studies have compared their performance. This study compares the performance of one morphology-based and four DNA-based (BIN, parsimony networks, ABGD, GMYC) methods on two groups of gelechioid moths. It examines 92 species of Finnish Gelechiinae and 103 species of Australian Elachistinae which were delineated by traditional taxonomy. The results reveal a striking difference in performance between the two taxa with all four DNA-based methods. OTU counts in the Elachistinae showed a wider range and a relatively low (ca. 65%) OTU match with reference species while OTU counts were more congruent and performance was higher (ca. 90%) in the Gelechiinae. Performance rose when only monophyletic species were compared, but the taxon-dependence remained. None of the DNA-based methods produced a correct match with non-monophyletic species, but singletons were handled well. A simulated test of morphospecies-grouping performed very poorly in revealing taxon diversity in these small, dull-colored moths. Despite the strong performance of analyses based on DNA barcodes, species delineated using single-locus mtDNA data are best viewed as OTUs that require validation by subsequent integrative taxonomic work. PMID:25849083

20 CFR 658.604 - Assessment and evaluation of program performance data.

Code of Federal Regulations, 2010 CFR

2010-04-01

..., whether overall or relative to a particular program activity, indicate poor program performance does not... that a State agency's performance is poor that the data may raise a presumption (prima facie case) that... performance data. 658.604 Section 658.604 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION...

Uncovering phenotypes of poor-pitch singing: the Sung Performance Battery (SPB)

PubMed Central

Berkowska, Magdalena; Dalla Bella, Simone

2013-01-01

Singing is as natural as speaking for humans. Increasing evidence shows that the layman can carry a tune (e.g., when asked to sing a well-known song or to imitate single pitches, intervals and short melodies). Yet, important individual differences exist in the general population with regard to singing proficiency. Some individuals are particularly inaccurate or imprecise in producing or imitating pitch information (poor-pitch singers), thus showing a variety of singing phenotypes. Unfortunately, so far there is not a standard set of tasks for assessing singing proficiency in the general population, allowing to uncover and characterize individual profiles of poor-pitch singing. Different tasks and analysis methods are typically used in various experiments, making the comparison of the results across studies arduous. To fill this gap we propose here a new tool for assessing singing proficiency (the Sung Performance Battery, SPB). The SPB starts from the assessment of participants' vocal range followed by five tasks: (1) single-pitch matching, (2) pitch-interval matching, (3) novel-melody matching, (4) singing from memory of familiar melodies (with lyrics and on a syllable), and (5) singing of familiar melodies (with lyrics and on a syllable) at a slow tempo indicated by a metronome. Data analysis via acoustical methods provides objective measures of pitch accuracy and precision in terms of absolute and relative pitch. The SPB has been tested in a group of 50 occasional singers. The results indicate that the battery is useful for characterizing proficient singing and for detecting cases of inaccurate and/or imprecise singing. PMID:24151475

Poor Executive Functions among Children with Moderate-into-Severe Asthma: Evidence from WCST Performance.

PubMed

Taha, Haitham

2017-01-01

Executive functions (EFs) measures of 27 asthmatic children, with general learning difficulties, were tested by using the Wisconsin card sorting test (WCST), and were compared to the performances of 30 non-asthmatic children with general learning difficulties. The results revealed that the asthmatic group has poor performance through all the WCST psychometric parameters and especially the perseverative errors one. The results were discussed in light of the postulation that poor EFs could be associated with the learning difficulties of asthmatic children. Neurophysiological framework has been suggested to explain the etiology of poor EFs among children with moderate into severe asthma.

Common Characteristics of Good and Poorly Performing PCC Pavements

DOT National Transportation Integrated Search

1998-01-01

This report documents the analysis and findings of a study to identify the site conditions and design/construction features of concrete pavements (JPCP, JRCP, CRCP) that lead to good performance and those that lead to poor performance. Data from Long...

Common Characteristics of Good and Poorly Performing AC Pavements

DOT National Transportation Integrated Search

1999-12-01

This report documents the analysis and findings of a study to identify the site conditions and design/construction features of : flexible pavements that lead to good performance and those that lead to poor performance. Data from the Long Term Pavemen...

Correlation between stressors and academic performance in second year medical students.

PubMed

Nuallaong, Winitra

2011-12-01

The present study aimed to find which type of stressors correlating to academic performance in second year medical students. One-hundred and eighty three second year medical students of Thammasat University participated in a three-week cross-sectional study. The self-report questionnaire consisted of Thai stress test, stress factors and examination grades referring academic performance were applied in the present study. Females felt stress more than males in severe, high, and medium level of stress. There was no low level of stress and no correlation between stress level and the entrance programs. Academic performance found relating to 1) fear of doing a mistake, 2) feeling of competition or comparison, 3) unilateral headache, 4) worrying, and 5) poor concentration. Students with poor concentration had significantly decreasing grade in the second year (p < 0.01). Interestingly, worrying, feeling of competition or comparison, and fear of doing a mistake correlated to increasing grade in some terms (p < 0.05). Specifically to poor concentration, there were medium linear association with fatigue, poor memory, feeling confused, feeling sad, feeling angry or irritable, changing appetite, and headache from stress (p < 0.01). Poor concentration was the only stressor significantly correlated with poorer academic performance. Poor concentration also correlated with physical, cognitive, and financial problems. The recommendation is to keep watching those issues in order to early detect problem about academic performance.

Automated assessment of early hypoxic brain edema in non-enhanced CT predicts outcome in patients after cardiac arrest.

PubMed

Hanning, Uta; Sporns, Peter Bernhard; Lebiedz, Pia; Niederstadt, Thomas; Zoubi, Tarek; Schmidt, Rene; Knecht, Stefan; Heindel, Walter; Kemmling, André

2016-07-01

Early prediction of potential neurological recovery in patients after cardiac arrest is challenging. Recent studies suggest that the densitrometic gray-white matter ratio (GWR) determined from cranial computed tomography (CT) scans may be a reliable predictor of poor outcome. We evaluated an automated, rater independent method to determine GWR in CT as an early objective imaging predictor of clinical outcome. We analyzed imaging data of 84 patients after cardiac arrest that underwent noncontrast CT within 24h after arrest. To determine GWR in CT we applied two methods using a recently published automated probabilistic gray-white matter segmentation algorithm (GWR_aut) and conventional manual measurements within gray-white regions of interest (GWR_man). Neurological outcome was graded by the cerebral performance category (CPC). As part of standard routine CPC was assessed by the treating physician in the intensive care unit at admission and at discharge to normal ward. The performance of GWR measures (automated and manual) to predict the binary clinical endpoints of poor (CPC3-5) and good outcome (CPC1-2) was assessed by ROC analysis with increasing discrimination thresholds. Results of GWR_aut were compared to GWR_man of two raters. Of 84 patients, 55 (65%) showed a poor outcome. ROC curve analysis revealed reliable outcome prediction of GWR_aut (AUC 0.860) and GWR_man (AUC 0.707 and 0.699, respectively). Predictive power of GWR_aut was higher than GWR_man by each rater (p=0.019 and p=0.021, respectively) at an optimal cut-off of 1.084 to predict poor outcome (optimal criterion with 92.7% sensitivity, 72.4% specificity). Interrater reliability of GWR_man by intra-class correlation coefficient (ICC) was moderate (0.551). Automated quantification of GWR in CT may be used as an objective observer-independent imaging marker for outcome in patients after cardiac arrest. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Natural Language Processing for Cohort Discovery in a Discharge Prediction Model for the Neonatal ICU.

PubMed

Temple, Michael W; Lehmann, Christoph U; Fabbri, Daniel

2016-01-01

Discharging patients from the Neonatal Intensive Care Unit (NICU) can be delayed for non-medical reasons including the procurement of home medical equipment, parental education, and the need for children's services. We previously created a model to identify patients that will be medically ready for discharge in the subsequent 2-10 days. In this study we use Natural Language Processing to improve upon that model and discern why the model performed poorly on certain patients. We retrospectively examined the text of the Assessment and Plan section from daily progress notes of 4,693 patients (103,206 patient-days) from the NICU of a large, academic children's hospital. A matrix was constructed using words from NICU notes (single words and bigrams) to train a supervised machine learning algorithm to determine the most important words differentiating poorly performing patients compared to well performing patients in our original discharge prediction model. NLP using a bag of words (BOW) analysis revealed several cohorts that performed poorly in our original model. These included patients with surgical diagnoses, pulmonary hypertension, retinopathy of prematurity, and psychosocial issues. The BOW approach aided in cohort discovery and will allow further refinement of our original discharge model prediction. Adequately identifying patients discharged home on g-tube feeds alone could improve the AUC of our original model by 0.02. Additionally, this approach identified social issues as a major cause for delayed discharge. A BOW analysis provides a method to improve and refine our NICU discharge prediction model and could potentially avoid over 900 (0.9%) hospital days.

Multiuser receiver for DS-CDMA signals in multipath channels: an enhanced multisurface method.

PubMed

Mahendra, Chetan; Puthusserypady, Sadasivan

2006-11-01

This paper deals with the problem of multiuser detection in direct-sequence code-division multiple-access (DS-CDMA) systems in multipath environments. The existing multiuser detectors can be divided into two categories: (1) low-complexity poor-performance linear detectors and (2) high-complexity good-performance nonlinear detectors. In particular, in channels where the orthogonality of the code sequences is destroyed by multipath, detectors with linear complexity perform much worse than the nonlinear detectors. In this paper, we propose an enhanced multisurface method (EMSM) for multiuser detection in multipath channels. EMSM is an intermediate piecewise linear detection scheme with a run-time complexity linear in the number of users. Its bit error rate performance is compared with existing linear detectors, a nonlinear radial basis function detector trained by the new support vector learning algorithm, and Verdu's optimal detector. Simulations in multipath channels, for both synchronous and asynchronous cases, indicate that it always outperforms all other linear detectors, performing nearly as well as nonlinear detectors.

The Effects of Maternal Postnatal Depression and Child Sex on Academic Performance at Age 16 Years: A Developmental Approach

ERIC Educational Resources Information Center

Murray, Lynne; Arteche, Adriane; Fearon, Pasco; Halligan, Sarah; Croudace, Tim; Cooper, Peter

2010-01-01

Background: Postnatal depression (PND) is associated with poor cognitive functioning in infancy and the early school years; long-term effects on academic outcome are not known. Method: Children of postnatally depressed (N = 50) and non-depressed mothers (N = 39), studied from infancy, were followed up at 16 years. We examined the effects on…

Low Cerebral Blood Volume Identifies Poor Outcome in Stent Retriever Thrombectomy

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

Protto, Sara, E-mail: sara.protto@pshp.fi; Pienimäki, Juha-Pekka; Seppänen, Janne

BackgroundMechanical thrombectomy (MT) is an efficient treatment of acute stroke caused by large-vessel occlusion. We evaluated the factors predicting poor clinical outcome (3-month modified Rankin Scale, mRS >2) although MT performed with modern stent retrievers.MethodsWe prospectively collected the clinical and imaging data of 105 consecutive anterior circulation stroke patients who underwent MT after multimodal CT imaging. Patients with occlusion of the internal carotid artery and/or middle cerebral artery up to the M2 segment were included. We recorded baseline clinical, procedural and imaging variables, technical outcome, 24-h imaging outcome and the clinical outcome. Differences between the groups were studied with appropriatemore » statistical tests and binary logistic regression analysis.ResultsLow cerebral blood volume Alberta stroke program early CT score (CBV-ASPECTS) was associated with poor clinical outcome (median 7 vs. 9, p = 0.01). Lower collateral score (CS) significantly predicted poor outcome in regression modelling with CS = 0 increasing the odds of poor outcome 4.4-fold compared to CS = 3 (95% CI 1.27–15.5, p = 0.02). Lower CBV-ASPECTS significantly predicted poor clinical outcome among those with moderate or severe stroke (OR 0.82, 95% CI 0.68–1, p = 0.05) or poor collateral circulation (CS 0–1, OR 0.66, 95% CI 0.48–0.90, p = 0.009) but not among those with mild strokes or good collaterals.ConclusionsCBV-ASPECTS estimating infarct core is a significant predictor of poor clinical outcome among anterior circulation stroke patients treated with MT, especially in the setting of poor collateral circulation and/or moderate or severe stroke.« less

Disciplinary processes and the management of poor performance among UK nurses: bad apple or systemic failure? A scoping study.

PubMed

Traynor, Michael; Stone, Katie; Cook, Hannah; Gould, Dinah; Maben, Jill

2014-03-01

The rise of managerialism within healthcare systems has been noted globally. This paper uses the findings of a scoping study to investigate the management of poor performance among nurses and midwives in the United Kingdom within this context. The management of poor performance among clinicians in the NHS has been seen as a significant policy problem. There has been a profound shift in the distribution of power between professional and managerial groups in many health systems globally. We examined literature published between 2000 and 10 to explore aspects of poor performance and its management. We used Web of Science, CINAHL, MEDLINE, British Nursing Index, HMIC, Cochrane Library and PubMed. Empirical data are limited but indicate that nurses and midwives are the clinical groups most likely to be suspended and that poor performance is often represented as an individual deficit. A focus on the individual as a source of trouble can serve as a distraction from more complex systematic problems. © 2013 John Wiley & Sons Ltd.

Does poor school performance cause later psychosocial problems among children in foster care? Evidence from national longitudinal registry data.

PubMed

Forsman, Hilma; Brännström, Lars; Vinnerljung, Bo; Hjern, Anders

2016-07-01

Research has shown that children in foster care are a high-risk group for adverse economic, social and health related outcomes in young adulthood. Children's poor school performance has been identified as a major risk factor for these poor later life outcomes. Aiming to support the design of effective intervention strategies, this study examines the hypothesized causal effect of foster children's poor school performance on subsequent psychosocial problems, here conceptualized as economic hardship, illicit drug use, and mental health problems, in young adulthood. Using the potential outcomes approach, longitudinal register data on more than 7500 Swedish foster children born 1973-1978 were analyzed by means of doubly robust treatment-effect estimators. The results show that poor school performance has a negative impact on later psychosocial problems net of observed background attributes and potential selection on unobservables, suggesting that the estimated effects allow for causal interpretations. Promotion of school performance may thus be a viable intervention path for policymakers and practitioners interested in improving foster children's overall life chances. Copyright © 2016 Elsevier Ltd. All rights reserved.

ANDRO-IVF: a novel protocol for poor responders to IVF controlled ovarian stimulation

PubMed Central

Bercaire, Ludmila; Nogueira, Sara MB; Lima, Priscila CM; Alves, Vanessa R; Donadio, Nilka; Dzik, Artur; Cavagna, Mario; Fanchin, Renato

2018-01-01

Objective This study aimed to assess a novel protocol designed to improve poor ovarian response through intra-ovarian androgenization. The endpoints were: number of oocytes and mature oocytes retrieved, fertilization, cancellation and pregnancy rates. Methods This prospective crossover study enrolled poor responders from previous ovarian stimulation cycles submitted to a novel protocol called ANDRO-IVF. The protocol included pretreatment with transdermal AndroGel(r) (Besins) 25 mg, oral letrozole 2.5 mg and subcutaneous hCG 2500 IU; cycle control was performed with estradiol valerate and micronized progesterone; ovarian stimulation was attained with gonadotropins FSH/LH 450 IU, GnRH antagonist and hCG 5000 IU. Results Fourteen poor responders were enrolled. One patient did not meet the inclusion criteria. Thirteen patients previously summited to the standard protocol were offered the ANDRO-IVF Protocol.-Standard Protocol: Mean age: 35.30 years; cancellation rate: 61.53%; mean number of MII oocytes retrieved per patient: 1.8; fertilization rate: 33.33%. Only two patients had embryo transfers, and none got pregnant.-ANDRO-IVF Protocol: Mean age: 35.83 years; cancellation rate: 7.69%; mean number of oocytes retrieved per patient: 5.58, MII oocytes: 3.91. ICSI was performed in 84.61% of the patients and a mean of 1.5 embryos were transferred per patient. Fertilization rate: 62.5%; cumulative pregnancy rate: 16.66%; mean duration of stimulation: 9.77 days. Conclusion ANDRO-IVF allows intra-ovarian androgenization by increasing serum and intra-follicular androgen levels and preventing androgen aromatization. This protocol apparently improved clinical outcomes of poor responders in parameters such as number of oocytes retrieved and clinical pregnancy rates. Further randomized controlled trials are needed to confirm these findings. PMID:29303236

Relationship between Poor Sleep and Daytime Cognitive Performance in Young Adults with Autism

ERIC Educational Resources Information Center

Limoges, Elyse; Bolduc, Christianne; Berthiaume, Claude; Mottron, Laurent; Godbout, Roger

2013-01-01

Poor sleep is a common feature in autism even though patients themselves do not necessarily complain. The impact of poor sleep on daytime cognitive functioning in autism is not well-known and we therefore investigated whether sleep in autism correlates with daytime cognitive performance. A battery of non-verbal tasks was administered, in the…

An improved method to detect correct protein folds using partial clustering.

PubMed

Zhou, Jianjun; Wishart, David S

2013-01-16

Structure-based clustering is commonly used to identify correct protein folds among candidate folds (also called decoys) generated by protein structure prediction programs. However, traditional clustering methods exhibit a poor runtime performance on large decoy sets. We hypothesized that a more efficient "partial" clustering approach in combination with an improved scoring scheme could significantly improve both the speed and performance of existing candidate selection methods. We propose a new scheme that performs rapid but incomplete clustering on protein decoys. Our method detects structurally similar decoys (measured using either C(α) RMSD or GDT-TS score) and extracts representatives from them without assigning every decoy to a cluster. We integrated our new clustering strategy with several different scoring functions to assess both the performance and speed in identifying correct or near-correct folds. Experimental results on 35 Rosetta decoy sets and 40 I-TASSER decoy sets show that our method can improve the correct fold detection rate as assessed by two different quality criteria. This improvement is significantly better than two recently published clustering methods, Durandal and Calibur-lite. Speed and efficiency testing shows that our method can handle much larger decoy sets and is up to 22 times faster than Durandal and Calibur-lite. The new method, named HS-Forest, avoids the computationally expensive task of clustering every decoy, yet still allows superior correct-fold selection. Its improved speed, efficiency and decoy-selection performance should enable structure prediction researchers to work with larger decoy sets and significantly improve their ab initio structure prediction performance.

An improved method to detect correct protein folds using partial clustering

PubMed Central

2013-01-01

Background Structure-based clustering is commonly used to identify correct protein folds among candidate folds (also called decoys) generated by protein structure prediction programs. However, traditional clustering methods exhibit a poor runtime performance on large decoy sets. We hypothesized that a more efficient “partial“ clustering approach in combination with an improved scoring scheme could significantly improve both the speed and performance of existing candidate selection methods. Results We propose a new scheme that performs rapid but incomplete clustering on protein decoys. Our method detects structurally similar decoys (measured using either Cα RMSD or GDT-TS score) and extracts representatives from them without assigning every decoy to a cluster. We integrated our new clustering strategy with several different scoring functions to assess both the performance and speed in identifying correct or near-correct folds. Experimental results on 35 Rosetta decoy sets and 40 I-TASSER decoy sets show that our method can improve the correct fold detection rate as assessed by two different quality criteria. This improvement is significantly better than two recently published clustering methods, Durandal and Calibur-lite. Speed and efficiency testing shows that our method can handle much larger decoy sets and is up to 22 times faster than Durandal and Calibur-lite. Conclusions The new method, named HS-Forest, avoids the computationally expensive task of clustering every decoy, yet still allows superior correct-fold selection. Its improved speed, efficiency and decoy-selection performance should enable structure prediction researchers to work with larger decoy sets and significantly improve their ab initio structure prediction performance. PMID:23323835

CAUSES OF POOR SEALANT PERFORMANCE IN SOIL-GAS- RESISTANT FOUNDATIONS

EPA Science Inventory

The paper discusses causes of poor sealant performance in soil-gas-resistant foundations. ealants for radon-resistant foundation construction must seal the gap between concrete sections. odern sealants have such low permeability that seal performance depends only on the permeabil...

Poor school performance.

PubMed

Karande, Sunil; Kulkarni, Madhuri

2005-11-01

Education is one of the most important aspects of human resource development. Poor school performance not only results in the child having a low self-esteem, but also causes significant stress to the parents. There are many reasons for children to under perform at school, such as, medical problems, below average intelligence, specific learning disability, attention deficit hyperactivity disorder, emotional problems, poor socio-cultural home environment, psychiatric disorders and even environmental causes. The information provided by the parents, classroom teacher and school counselor about the child's academic difficulties guides the pediatrician to form an initial diagnosis. However, a multidisciplinary evaluation by an ophthalmologist, otolaryngologist, counselor, clinical psychologist, special educator, and child psychiatrist is usually necessary before making the final diagnosis. It is important to find the reason(s) for a child's poor school performance and come up with a treatment plan early so that the child can perform up to full potential.

Comparison of adaptive critic-based and classical wide-area controllers for power systems.

PubMed

Ray, Swakshar; Venayagamoorthy, Ganesh Kumar; Chaudhuri, Balarko; Majumder, Rajat

2008-08-01

An adaptive critic design (ACD)-based damping controller is developed for a thyristor-controlled series capacitor (TCSC) installed in a power system with multiple poorly damped interarea modes. The performance of this ACD computational intelligence-based method is compared with two classical techniques, which are observer-based state-feedback (SF) control and linear matrix inequality LMI-H(infinity) robust control. Remote measurements are used as feedback signals to the wide-area damping controller for modulating the compensation of the TCSC. The classical methods use a linearized model of the system whereas the ACD method is purely measurement-based, leading to a nonlinear controller with fixed parameters. A comparative analysis of the controllers' performances is carried out under different disturbance scenarios. The ACD-based design has shown promising performance with very little knowledge of the system compared to classical model-based controllers. This paper also discusses the advantages and disadvantages of ACDs, SF, and LMI-H(infinity).

A comprehensive method for GNSS data quality determination to improve ionospheric data analysis.

PubMed

Kim, Minchan; Seo, Jiwon; Lee, Jiyun

2014-08-14

Global Navigation Satellite Systems (GNSS) are now recognized as cost-effective tools for ionospheric studies by providing the global coverage through worldwide networks of GNSS stations. While GNSS networks continue to expand to improve the observability of the ionosphere, the amount of poor quality GNSS observation data is also increasing and the use of poor-quality GNSS data degrades the accuracy of ionospheric measurements. This paper develops a comprehensive method to determine the quality of GNSS observations for the purpose of ionospheric studies. The algorithms are designed especially to compute key GNSS data quality parameters which affect the quality of ionospheric product. The quality of data collected from the Continuously Operating Reference Stations (CORS) network in the conterminous United States (CONUS) is analyzed. The resulting quality varies widely, depending on each station and the data quality of individual stations persists for an extended time period. When compared to conventional methods, the quality parameters obtained from the proposed method have a stronger correlation with the quality of ionospheric data. The results suggest that a set of data quality parameters when used in combination can effectively select stations with high-quality GNSS data and improve the performance of ionospheric data analysis.

A Comprehensive Method for GNSS Data Quality Determination to Improve Ionospheric Data Analysis

PubMed Central

Kim, Minchan; Seo, Jiwon; Lee, Jiyun

2014-01-01

Global Navigation Satellite Systems (GNSS) are now recognized as cost-effective tools for ionospheric studies by providing the global coverage through worldwide networks of GNSS stations. While GNSS networks continue to expand to improve the observability of the ionosphere, the amount of poor quality GNSS observation data is also increasing and the use of poor-quality GNSS data degrades the accuracy of ionospheric measurements. This paper develops a comprehensive method to determine the quality of GNSS observations for the purpose of ionospheric studies. The algorithms are designed especially to compute key GNSS data quality parameters which affect the quality of ionospheric product. The quality of data collected from the Continuously Operating Reference Stations (CORS) network in the conterminous United States (CONUS) is analyzed. The resulting quality varies widely, depending on each station and the data quality of individual stations persists for an extended time period. When compared to conventional methods, the quality parameters obtained from the proposed method have a stronger correlation with the quality of ionospheric data. The results suggest that a set of data quality parameters when used in combination can effectively select stations with high-quality GNSS data and improve the performance of ionospheric data analysis. PMID:25196005

Investigating the use of a rational Runge Kutta method for transport modelling

NASA Astrophysics Data System (ADS)

Dougherty, David E.

An unconditionally stable explicit time integrator has recently been developed for parabolic systems of equations. This rational Runge Kutta (RRK) method, proposed by Wambecq 1 and Hairer 2, has been applied by Liu et al.3 to linear heat conduction problems in a time-partitioned solution context. An important practical question is whether the method has application for the solution of (nearly) hyperbolic equations as well. In this paper the RRK method is applied to a nonlinear heat conduction problem, the advection-diffusion equation, and the hyperbolic Buckley-Leverett problem. The method is, indeed, found to be unconditionally stable for the linear heat conduction problem and performs satisfactorily for the nonlinear heat flow case. A heuristic limitation on the utility of RRK for the advection-diffusion equation arises in the Courant number; for the second-order accurate one-step two-stage RRK method, a limiting Courant number of 2 applies. First order upwinding is not as effective when used with RRK as with Euler one-step methods. The method is found to perform poorly for the Buckley-Leverett problem.

Limb Position Tolerant Pattern Recognition for Myoelectric Prosthesis Control with Adaptive Sparse Representations From Extreme Learning.

PubMed

Betthauser, Joseph L; Hunt, Christopher L; Osborn, Luke E; Masters, Matthew R; Levay, Gyorgy; Kaliki, Rahul R; Thakor, Nitish V

2018-04-01

Myoelectric signals can be used to predict the intended movements of an amputee for prosthesis control. However, untrained effects like limb position changes influence myoelectric signal characteristics, hindering the ability of pattern recognition algorithms to discriminate among motion classes. Despite frequent and long training sessions, these deleterious conditional influences may result in poor performance and device abandonment. We present a robust sparsity-based adaptive classification method that is significantly less sensitive to signal deviations resulting from untrained conditions. We compare this approach in the offline and online contexts of untrained upper-limb positions for amputee and able-bodied subjects to demonstrate its robustness compared against other myoelectric classification methods. We report significant performance improvements () in untrained limb positions across all subject groups. The robustness of our suggested approach helps to ensure better untrained condition performance from fewer training conditions. This method of prosthesis control has the potential to deliver real-world clinical benefits to amputees: better condition-tolerant performance, reduced training burden in terms of frequency and duration, and increased adoption of myoelectric prostheses.

A Technique to Determine the Self-Noise of Seismic Sensors for Performance Screening

NASA Astrophysics Data System (ADS)

Rademacher, H.; Hart, D.; Guralp, C.

2012-04-01

Seismic noise affects the performance of a seismic sensor and is thereby a limiting factor for the detection threshold of monitoring networks. Among the various sources of noise, the intrinsic self-noise of a seismic sensor is most diffcult to determine, because it is mostly masked by natural and anthropogenic ground noise and is also affected by the noise characteristic of the digitizer. Here we present a new technique to determine the self-noise of a seismic system (digitizer + sensors). It is based on a method introduced by Sleeman et al. (2005) to test the noise performance of digitizers. We infer the self-noise of a triplet of identical sensors by comparing coherent waveforms over a wide spectral band across the set-up. We will show first results from a proof-of-concept study done in a vault near Albuquerque, New Mexico. We will show, how various methods of shielding the sensors affect the results of this technique. This method can also be used as a means of quality control during sensor production, because poorly performing sensors can easily be identified.

Mental state attribution in schizophrenia: what distinguishes patients with "poor" from patients with "fair" mentalising skills?

PubMed

Brüne, M; Schaub, D

2012-07-01

Although many patients with schizophrenia are impaired in mental states attribution abilities, a significant number perform within normal or near-normal ranges in mental state attribution tasks. No studies have analysed cognitive or behavioural differences between patients with - to some extent - preserved mental state attribution skills and those with poor mentalising abilities. To examine characteristics of "poor" and "fair" mentalisers, 58 patients with schizophrenia performed a mental state attribution task, a test of general intelligence, and two executive functioning tests. "Poor" and "fair" mentalising skills were defined according to a median-split procedure; the median score in the patient group was also within two standard deviations of the control group. In addition, patients' social behavioural skills and psychopathological profiles were rated. Patients performing within normal or near normal ranges on the mental state attribution task had fewer social behavioural abnormalities than patients with poor mentalising abilities (even when controlled for intelligence), but did not differ in executive functioning. Fair mental state performers showed less disorganisation and excitement symptoms than poor performers. The degree of disorganisation mediated the influence of mental state attribution on social behavioural skills. Schizophrenia patients with (partially) preserved mentalising skills have fewer behavioural problems in the social domain than patients with poor mentalising abilities. Conceptual disorganisation mediates the prediction of social behavioural skills through mentalising skills, suggesting that disorganised patients may require special attention regarding social-cognitive skills training. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

Malaria is associated with poor school performance in an endemic area of the Brazilian Amazon

PubMed Central

Vitor-Silva, Sheila; Reyes-Lecca, Roberto C; Pinheiro, Tamam RA; Lacerda, Marcus VG

2009-01-01

Background Approximately 40% of the world's population is at risk for malaria. In highly endemic tropical areas, malaria is a major cause of morbidity and mortality during infancy. There is a complex interrelationship between malaria, malnutrition and intestinal helminths, and this may impair cognitive development in children. The aim of this study was to determine the relationship between malaria and school performance in children living in an endemic area where Plasmodium vivax is the species responsible for most of the cases. Methods The study was conducted in the Municipality of Careiro, Amazonas, Brazil, with five to14 year-old children, studying the first eight grades of public school, during the year 2008. After an initial active case detection, during nine months of follow-up, passive malaria cases detection was instituted, through a thick blood smear performed in every child with fever. School performance was evaluated by the final notes in Mathematics and Portuguese Language. Performance was considered poor when either of the final notes in these disciplines was below the 50th percentile for the respective class and grade. Results The total number of students followed-up in the cohort was 198. Malarial attacks were reported in 70 (35.4%) of these students, with no cases of severe disease. Plasmodium vivax was detected in 69.2% of the attacks, Plasmodium falciparum in 25.5% and both species in 5.3%. In the multivariate analysis, adjusting for age, mother's education, time living in the study area and school absenteeism, presenting with at least one episode of malaria independently predicted a poor performance at school [OR = 1.91 (1.04-3.54); p = 0.039]. Conclusion Non-severe malaria compromises the school performance of children even during a nine-month follow-up, potentially contributing to the maintenance of underdevelopment in countries endemic for malaria. This is the first evidence of such impact in Latin America, where P. vivax is responsible for the majority of the cases. PMID:19835584

Validation of a high-performance size-exclusion chromatography method to determine and characterize β-glucans in beer wort using a triple-detector array.

PubMed

Tomasi, Ivan; Marconi, Ombretta; Sileoni, Valeria; Perretti, Giuseppe

2017-01-01

Beer wort β-glucans are high-molecular-weight non-starch polysaccharides of that are great interest to the brewing industries. Because glucans can increase the viscosity of the solutions and form gels, hazes, and precipitates, they are often related to poor lautering performance and beer filtration problems. In this work, a simple and suitable method was developed to determine and characterize β-glucans in beer wort using size exclusion chromatography coupled with a triple-detector array, which is composed of a light scatterer, a viscometer, and a refractive-index detector. The method performances are comparable to the commercial reference method as result from the statistical validation and enable one to obtain interesting parameters of β-glucan in beer wort, such as the molecular weight averages, fraction description, hydrodynamic radius, intrinsic viscosity, polydispersity and Mark-Houwink parameters. This characterization can be useful in brewing science to understand filtration problems, which are not always explained through conventional analysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of exposure to good vs poor medical trainee performance on attending physician ratings of subsequent performances.

PubMed

Yeates, Peter; O'Neill, Paul; Mann, Karen; Eva, Kevin W

2012-12-05

Competency-based models of education require assessments to be based on individuals' capacity to perform, yet the nature of human judgment may fundamentally limit the extent to which such assessment is accurately possible. To determine whether recent observations of the Mini Clinical Evaluation Exercise (Mini-CEX) performance of postgraduate year 1 physicians influence raters' scores of subsequent performances, consistent with either anchoring bias (scores biased similar to previous experience) or contrast bias (scores biased away from previous experience). Internet-based randomized, blinded experiment using videos of Mini-CEX assessments of postgraduate year 1 trainees interviewing new internal medicine patients. Participants were 41 attending physicians from England and Wales experienced with the Mini-CEX, with 20 watching and scoring 3 good trainee performances and 21 watching and scoring 3 poor performances. All then watched and scored the same 3 borderline video performances. The study was completed between July and November 2011. The primary outcome was scores assigned to the borderline videos, using a 6-point Likert scale (anchors included: 1, well below expectations; 3, borderline; 6, well above expectations). Associations were tested in a multivariable analysis that included participants' sex, years of practice, and the stringency index (within-group z score of initial 3 ratings). The mean rating scores assigned by physicians who viewed borderline video performances following exposure to good performances was 2.7 (95% CI, 2.4-3.0) vs 3.4 (95% CI, 3.1-3.7) following exposure to poor performances (difference of 0.67 [95% CI, 0.28-1.07]; P = .001). Borderline videos were categorized as consistent with failing scores in 33 of 60 assessments (55%) in those exposed to good performances and in 15 of 63 assessments (24%) in those exposed to poor performances (P < .001). They were categorized as consistent with passing scores in 5 of 60 assessments (8.3%) in those exposed to good performances compared with 25 of 63 assessments (39.5%) in those exposed to poor performances (P < .001). Sex and years of attending practice were not associated with scores. The priming condition (good vs poor performances) and the stringency index jointly accounted for 45% of the observed variation in raters' scores for the borderline videos (P < .001). In an experimental setting, attending physicians exposed to videos of good medical trainee performances rated subsequent borderline performances lower than those who had been exposed to poor performances, consistent with a contrast bias.

Comparison of parameter-adapted segmentation methods for fluorescence micrographs.

PubMed

Held, Christian; Palmisano, Ralf; Häberle, Lothar; Hensel, Michael; Wittenberg, Thomas

2011-11-01

Interpreting images from fluorescence microscopy is often a time-consuming task with poor reproducibility. Various image processing routines that can help investigators evaluate the images are therefore useful. The critical aspect for a reliable automatic image analysis system is a robust segmentation algorithm that can perform accurate segmentation for different cell types. In this study, several image segmentation methods were therefore compared and evaluated in order to identify the most appropriate segmentation schemes that are usable with little new parameterization and robustly with different types of fluorescence-stained cells for various biological and biomedical tasks. The study investigated, compared, and enhanced four different methods for segmentation of cultured epithelial cells. The maximum-intensity linking (MIL) method, an improved MIL, a watershed method, and an improved watershed method based on morphological reconstruction were used. Three manually annotated datasets consisting of 261, 817, and 1,333 HeLa or L929 cells were used to compare the different algorithms. The comparisons and evaluations showed that the segmentation performance of methods based on the watershed transform was significantly superior to the performance of the MIL method. The results also indicate that using morphological opening by reconstruction can improve the segmentation of cells stained with a marker that exhibits the dotted surface of cells. Copyright © 2011 International Society for Advancement of Cytometry.

Strategies to improve the performance of learners in a nursing college. Part I: Issues pertaining to nursing education.

PubMed

Waterson, E; Harms, E; Qupe, L; Maritz, J; Manning, M; Makobe, K; Chabeli, M

2006-05-01

The aim of this contextual, exploratory, descriptive and qualitative study was to describe strategies to improve the performance of learners in a nursing college. The article seeks to deal with factors relating to nursing education that contribute to the poor performance of learners and to outline related strategies to improve the situation. Three focus group interviews were conducted. One group was formed by seven tutors, and the other two groups were formed by fourth-year learners following a four-year comprehensive diploma course. All participants voluntarily took part in the study. Data was analyzed using the descriptive method of open coding by Tesch (in Creswell, 1994:154-156). Trustworthiness was ensured in accordance with Lincoln and Guba's (1985:290-326) principles of credibility, conformability, transferability and dependability. The findings were categorized into issues pertaining to nursing education as follows: curriculum overload; lack of theory and practice integration; teaching and assessment methods that do not promote critical thinking; tutors' lack of skills and experience; inadequate preparation of tutors for lectures; insufficient knowledge of tutors regarding outcomes-based education approach to teaching and learning; inadequate process of remedial teaching; discrepancies between tutors' marking; lack of clinical role-models and high expectations from the affiliated university as regards standards of nursing development programme by the staff development committee of the nursing college under study for implementation. Future research should focus on the effectiveness of the described strategies to improve the learners' performance. It is also recommended that similar studies be conducted or replicated in other nursing colleges to address the problem of poor performance of learners engaged in a four-year comprehensive diploma course.

Poor Gait Performance and Prediction of Dementia: Results From a Meta-Analysis.

PubMed

Beauchet, Olivier; Annweiler, Cédric; Callisaya, Michele L; De Cock, Anne-Marie; Helbostad, Jorunn L; Kressig, Reto W; Srikanth, Velandai; Steinmetz, Jean-Paul; Blumen, Helena M; Verghese, Joe; Allali, Gilles

2016-06-01

Poor gait performance predicts risk of developing dementia. No structured critical evaluation has been conducted to study this association yet. The aim of this meta-analysis was to systematically examine the association of poor gait performance with incidence of dementia. An English and French Medline search was conducted in June 2015, with no limit of date, using the medical subject headings terms "Gait" OR "Gait Disorders, Neurologic" OR "Gait Apraxia" OR "Gait Ataxia" AND "Dementia" OR "Frontotemporal Dementia" OR "Dementia, Multi-Infarct" OR "Dementia, Vascular" OR "Alzheimer Disease" OR "Lewy Body Disease" OR "Frontotemporal Dementia With Motor Neuron Disease" (Supplementary Concept). Poor gait performance was defined by standardized tests of walking, and dementia was diagnosed according to international consensus criteria. Four etiologies of dementia were identified: any dementia, Alzheimer disease (AD), vascular dementia (VaD), and non-AD (ie, pooling VaD, mixed dementias, and other dementias). Fixed effects meta-analyses were performed on the estimates in order to generate summary values. Of the 796 identified abstracts, 12 (1.5%) were included in this systematic review and meta-analysis. Poor gait performance predicted dementia [pooled hazard ratio (HR) combined with relative risk and odds ratio = 1.53 with P < .001 for any dementia, pooled HR = 1.79 with P < .001 for VaD, HR = 1.89 with P value < .001 for non-AD]. Findings were weaker for predicting AD (HR = 1.03 with P value = .004). This meta-analysis provides evidence that poor gait performance predicts dementia. This association depends on the type of dementia; poor gait performance is a stronger predictor of non-AD dementias than AD. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Hypofractionated Radiotherapy for Complicated Bone Metastases in Patients with Poor Performance Status: A Phase II International Trial.

PubMed

Silva, Mauricio F; Marta, Gustavo N; Lisboa, Felipe P C; Watte, Guilherme; Trippa, Fabio; Maranzano, Ernesto; da Motta, Neiro W; Popovic, Marko; Ha, Tuan; Burmeister, Bryan; Chow, Edward

2017-06-01

Purpose To evaluate the efficacy and safety of hypofractionated radiotherapy (16 Gy in 2 fractions, 1 week apart) in patients with complicated bone metastases and poor performance status. Methods A prospective single-arm phase II clinical trial was conducted from July 2014 to May 2016. The primary endpoint was pain response as defined in the International Consensus on Palliative Radiotherapy Endpoints. Secondary endpoints included quality of life as measured by quality of life questionnaire (QLQ) PAL-15 and QLQ-BM22 European Organisation for Research and Treatment of Cancer guidelines, pain flare, adverse events, re-irradiation, and skeletal complications. Results Fifty patients were enrolled. There were 23 men with a median age of 58 years (range 26-86). Of the 50 patients, 38 had an extraosseous soft tissue component, 18 needed postsurgical radiation, 3 had neuropathic pain, and 3 had an impending fracture in a weight-bearing bone. At 2 months, 33 patients were alive (66%). Four (12.5%) had a complete response and 12 (37.5%) had a partial response. A statistically significant improvement was seen in the functional interference (p = 0.01) and psychosocial aspects (p = 0.03) of the BM22. No patient had spinal cord compression. One patient required surgery for pathologic fracture, and another re-irradiation. Conclusions Hypofractionated radiotherapy (16 Gy in 2 fractions of 8 Gy 1 week apart) achieved satisfactory pain relief and safety results in patients with complicated bone metastases and poor performance status.

Demand Creation for Polio Vaccine in Persistently Poor-Performing Communities of Northern Nigeria: 2013–2014

PubMed Central

Warigon, Charity; Mkanda, Pascal; Muhammed, Ado; Etsano, Andrew; Korir, Charles; Bawa, Samuel; Gali, Emmanuel; Nsubuga, Peter; Erbeto, Tesfaya B.; Gerlong, George; Banda, Richard; Yehualashet, Yared G.; Vaz, Rui G.

2016-01-01

Introduction. Poliomyelitis remains a global threat despite availability of oral polio vaccine (OPV), proven to reduce the burden of the paralyzing disease. In Nigeria, children continue to miss the opportunity to be fully vaccinated, owing to factors such as unmet health needs and low uptake in security-compromised and underserved communities. We describe the implementation and evaluation of several activities to create demand for polio vaccination in persistently poor-performing local government areas (LGAs). Methods. We assessed the impact of various polio-related interventions, to measure the contribution of demand creation activities in 77 LGAs at very high risk for polio, located across 10 states in northern Nigeria. Interventions included provision of commodities along with the polio vaccine. Results. There was an increasing trend in the number of children reached by different demand creation interventions. A total of 4 819 847 children were vaccinated at health camps alone. There was a reduction in the number of wards in which >10% of children were missed by supplementary immunization activities due to noncompliance with vaccination recommendations, a rise in the proportion of children who received ≥4 OPV doses, and a decrease in the proportion of children who were underimmunized or unimmunized. Conclusions. Demand creation interventions increased the uptake of polio vaccines in persistently poor-performing high-risk communities in northern Nigeria during September 2013–November 2014. PMID:26908717

Improving operational land surface model canopy evapotranspiration in Africa using a direct remote sensing approach

NASA Astrophysics Data System (ADS)

Marshall, M.; Tu, K.; Funk, C.; Michaelsen, J.; Williams, P.; Williams, C.; Ardö, J.; Boucher, M.; Cappelaere, B.; de Grandcourt, A.; Nickless, A.; Nouvellon, Y.; Scholes, R.; Kutsch, W.

2013-03-01

Climate change is expected to have the greatest impact on the world's economically poor. In the Sahel, a climatically sensitive region where rain-fed agriculture is the primary livelihood, expected decreases in water supply will increase food insecurity. Studies on climate change and the intensification of the water cycle in sub-Saharan Africa are few. This is due in part to poor calibration of modeled evapotranspiration (ET), a key input in continental-scale hydrologic models. In this study, a remote sensing model of transpiration (the primary component of ET), driven by a time series of vegetation indices, was used to substitute transpiration from the Global Land Data Assimilation System realization of the National Centers for Environmental Prediction, Oregon State University, Air Force, and Hydrology Research Laboratory at National Weather Service Land Surface Model (GNOAH) to improve total ET model estimates for monitoring purposes in sub-Saharan Africa. The performance of the hybrid model was compared against GNOAH ET and the remote sensing method using eight eddy flux towers representing major biomes of sub-Saharan Africa. The greatest improvements in model performance were at humid sites with dense vegetation, while performance at semi-arid sites was poor, but better than the models before hybridization. The reduction in errors using the hybrid model can be attributed to the integration of a simple canopy scheme that depends primarily on low bias surface climate reanalysis data and is driven primarily by a time series of vegetation indices.

Relative risk of probabilistic category learning deficits in patients with schizophrenia and their siblings

PubMed Central

Weickert, Thomas W.; Goldberg, Terry E.; Egan, Michael F.; Apud, Jose A.; Meeter, Martijn; Myers, Catherine E.; Gluck, Mark A; Weinberger, Daniel R.

2010-01-01

Background While patients with schizophrenia display an overall probabilistic category learning performance deficit, the extent to which this deficit occurs in unaffected siblings of patients with schizophrenia is unknown. There are also discrepant findings regarding probabilistic category learning acquisition rate and performance in patients with schizophrenia. Methods A probabilistic category learning test was administered to 108 patients with schizophrenia, 82 unaffected siblings, and 121 healthy participants. Results Patients with schizophrenia displayed significant differences from their unaffected siblings and healthy participants with respect to probabilistic category learning acquisition rates. Although siblings on the whole failed to differ from healthy participants on strategy and quantitative indices of overall performance and learning acquisition, application of a revised learning criterion enabling classification into good and poor learners based on individual learning curves revealed significant differences between percentages of sibling and healthy poor learners: healthy (13.2%), siblings (34.1%), patients (48.1%), yielding a moderate relative risk. Conclusions These results clarify previous discrepant findings pertaining to probabilistic category learning acquisition rate in schizophrenia and provide the first evidence for the relative risk of probabilistic category learning abnormalities in unaffected siblings of patients with schizophrenia, supporting genetic underpinnings of probabilistic category learning deficits in schizophrenia. These findings also raise questions regarding the contribution of antipsychotic medication to the probabilistic category learning deficit in schizophrenia. The distinction between good and poor learning may be used to inform genetic studies designed to detect schizophrenia risk alleles. PMID:20172502

Effect of hydrotalcite-like compounds on the aqueous solubility of some poorly water-soluble drugs.

PubMed

Ambrogi, Valeria; Fardella, Giuseppe; Grandolini, Giuliano; Nocchetti, Morena; Perioli, Luana

2003-07-01

A new approach of improving drug dissolution properties is described. This method exploits the property of a carrier owing to the hydrotalcite-type anionic clays (HTlc). HTlc is an inorganic layered solid that lodges anionic compounds among its layers. As HTlc dissolves at acidic pH values (pH < 4), the anions intercalated among the layers are promptly released in the medium. In this article some nonsteroidal antiinflammatory drugs were chosen as models of poorly water-soluble drugs. They were intercalated in HTlc and solubility measurements in acidic medium were performed. A remarkable improvement of drug solubility was observed especially in the case of indomethacin. Copyright 2003 Wiley-Liss, Inc. and the American Pharmacists Association

A Bayesian modification to the Jelinski-Moranda software reliability growth model

NASA Technical Reports Server (NTRS)

Littlewood, B.; Sofer, A.

1983-01-01

The Jelinski-Moranda (JM) model for software reliability was examined. It is suggested that a major reason for the poor results given by this model is the poor performance of the maximum likelihood method (ML) of parameter estimation. A reparameterization and Bayesian analysis, involving a slight modelling change, are proposed. It is shown that this new Bayesian-Jelinski-Moranda model (BJM) is mathematically quite tractable, and several metrics of interest to practitioners are obtained. The BJM and JM models are compared by using several sets of real software failure data collected and in all cases the BJM model gives superior reliability predictions. A change in the assumption which underlay both models to present the debugging process more accurately is discussed.

Capability of insulator study by photoemission electron microscopy at SPring-8.

PubMed

Ohkochi, Takuo; Kotsugi, Masato; Yamada, Keisuke; Kawano, Kenji; Horiba, Koji; Kitajima, Fumio; Oura, Masaki; Shiraki, Susumu; Hitosugi, Taro; Oshima, Masaharu; Ono, Teruo; Kinoshita, Toyohiko; Muro, Takayuki; Watanabe, Yoshio

2013-07-01

The observation method of photoemission electron microscopy (PEEM) on insulating samples has been established in an extremely simple way. Surface conductivity is induced locally on an insulating surface by continuous radiation of soft X-rays, and Au films close to the area of interest allow the accumulated charges on the insulated area to be released to ground level. Magnetic domain observations of a NiZn ferrite, local X-ray absorption spectroscopy of sapphire, high-resolution imaging of a poorly conducting Li0.9CoO2 film surface, and Au pattern evaporation on a fine rock particle are demonstrated. Using this technique, all users' experiments on poorly conducting samples have been performed successfully at the PEEM experimental station of SPring-8.

Bile salts-containing vesicles: promising pharmaceutical carriers for oral delivery of poorly water-soluble drugs and peptide/protein-based therapeutics or vaccines.

PubMed

Aburahma, Mona Hassan

2016-07-01

Most of the new drugs, biological therapeutics (proteins/peptides) and vaccines have poor performance after oral administration due to poor solubility or degradation in the gastrointestinal tract (GIT). Though, vesicular carriers exemplified by liposomes or niosomes can protect the entrapped agent to a certain extent from degradation. Nevertheless, the harsh GIT environment exemplified by low pH, presence of bile salts and enzymes limits their capabilities by destabilizing them. In response to that, more resistant bile salts-containing vesicles (BS-vesicles) were developed by inclusion of bile salts into lipid bilayers constructs. The effectiveness of orally administrated BS-vesicles in improving the performance of vesicles has been demonstrated in researches. Yet, these attempts did not gain considerable attention. This is the first review that provides a comprehensive overview of utilizing BS-vesicles as a promising pharmaceutical carrier with a special focus on their successful applications in oral delivery of therapeutic macromolecules and vaccines. Insights on the possible mechanisms by which BS-vesicles improve the oral bioavailability of the encapsulated drug or immunological response of entrapped vaccine are explained. In addition, methods adopted to prepare and characterize BS-vesicles are described. Finally, the gap in the scientific researches tackling BS-vesicles that needs to be addressed is highlighted.

The Longitudinal Impact of Cognitive Speed of Processing Training on Driving Mobility

PubMed Central

Edwards, Jerri D.; Myers, Charlsie; Ross, Lesley A.; Roenker, Daniel L.; Cissell, Gayla M.; McLaughlin, Alexis M.; Ball, Karlene K.

2009-01-01

Purpose: To examine how cognitive speed of processing training affects driving mobility across a 3-year period among older drivers. Design and Methods: Older drivers with poor Useful Field of View (UFOV) test performance (indicating greater risk for subsequent at-fault crashes and mobility declines) were randomly assigned to either a speed of processing training or a social and computer contact control group. Driving mobility of these 2 groups was compared with a group of older adults who did not score poorly on the UFOV test (reference group) across a 3-year period. Results: Older drivers with poor UFOV test scores who did not receive training experienced greater mobility declines as evidenced by decreased driving exposure and space and increased driving difficulty at 3 years. Those at risk for mobility decline who received training did not differ across the 3-year period from older adults in the reference group with regard to driving exposure, space, and most aspects of driving difficulty. Implications: Cognitive speed of processing training can not only improve cognitive performance but also protect against mobility declines among older drivers. Scientifically proven cognitive training regimens have the potential to enhance the everyday lives of older adults. PMID:19491362

A Multi-Step Pathway Connecting Short Sleep Duration to Daytime Somnolence, Reduced Attention, and Poor Academic Performance: An Exploratory Cross-Sectional Study in Teenagers

PubMed Central

Perez-Lloret, Santiago; Videla, Alejandro J.; Richaudeau, Alba; Vigo, Daniel; Rossi, Malco; Cardinali, Daniel P.; Perez-Chada, Daniel

2013-01-01

Background: A multi-step causality pathway connecting short sleep duration to daytime somnolence and sleepiness leading to reduced attention and poor academic performance as the final result can be envisaged. However this hypothesis has never been explored. Objective: To explore consecutive correlations between sleep duration, daytime somnolence, attention levels, and academic performance in a sample of school-aged teenagers. Methods: We carried out a survey assessing sleep duration and daytime somnolence using the Pediatric Daytime Sleepiness Scale (PDSS). Sleep duration variables included week-days' total sleep time, usual bedtimes, and absolute weekdayto-weekend sleep time difference. Attention was assessed by d2 test and by the coding subtest from the WISC-IV scale. Academic performance was obtained from literature and math grades. Structural equation modeling was used to assess the independent relationships between these variables, while controlling for confounding effects of other variables, in one single model. Standardized regression weights (SWR) for relationships between these variables are reported. Results: Study sample included 1,194 teenagers (mean age: 15 years; range: 13-17 y). Sleep duration was inversely associated with daytime somnolence (SWR = -0.36, p < 0.01) while sleepiness was negatively associated with attention (SWR = -0.13, p < 0.01). Attention scores correlated positively with academic results (SWR = 0.18, p < 0.01). Daytime somnolence correlated negatively with academic achievements (SWR = -0.16, p < 0.01). The model offered an acceptable fit according to usual measures (RMSEA = 0.0548, CFI = 0.874, NFI = 0.838). A Sobel test confirmed that short sleep duration influenced attention through daytime somnolence (p < 0.02), which in turn influenced academic achievements through reduced attention (p < 0.002). Conclusions: Poor academic achievements correlated with reduced attention, which in turn was related to daytime somnolence. Somnolence correlated with short sleep duration. Citation: Perez-Lloret S; Videla AJ; Richaudeau A; Vigo D; Rossi M; Cardinali DP; Perez-Chada D. A multi-step pathway connecting short sleep duration to daytime somnolence, reduced attention, and poor academic performance: an exploratory cross-sectional study in teenagers. J Clin Sleep Med 2013;9(5):469-473. PMID:23674938

Multiplex PCR detection of Cryptosporidium sp, Giardia lamblia and Entamoeba histolytica directly from dried stool samples from Guinea-Bissauan children with diarrhoea.

PubMed

Mero, Sointu; Kirveskari, Juha; Antikainen, Jenni; Ursing, Johan; Rombo, Lars; Kofoed, Poul-Erik; Kantele, Anu

2017-09-01

In developing countries, diarrhoea is the most common cause of death for children under five years of age, with Giardia lamblia, Cryptosporidium and Entamoeba histolytica as the most frequent pathogenic parasites. Traditional microscopy for stool parasites has poor sensitivity and specificity, while new molecular methods may provide more accurate diagnostics. In poor regions with sample storage hampered by uncertain electricity supply, research would benefit from a method capable of analysing dried stools. A real-time multiplex PCR method with internal inhibition control was developed for detecting Giardia lamblia, Cryptosporidium hominis/parvum and Entamoeba histolytica directly from stool specimens. Applicability to dried samples was checked by comparing with fresh ones in a small test material. Finally, the assay was applied to dried specimens collected from Guinea-Bissauan children with diarrhoea. The PCR's analytical sensitivity limit was 0.1 ng/ml for G. lamblia DNA, 0.01 ng/ml for E. histolytica DNA and 0.1 ng/ml for Cryptosporidium sp. In the test material, the assay performed similarly with fresh and dried stools. Of the 52 Guinea-Bissauan samples, local microscopy revealed a parasite in 15%, while PCR detected 62% positive for at least one parasite: 44% of the dried samples had Giardia, 23% Cryptosporidium and 0% E. histolytica. Our new multiplex real-time PCR for protozoa presents a sensitive method applicable to dried samples. As proof of concept, it worked well on stools collected from Guinea-Bissauan children with diarrhoea. It provides an epidemiological tool for analysing dried specimens from regions poor in resources.

Surface Modified Pinecone Shaped Hierarchical Structure Fluorinated Mesocarbon Microbeads for Ultrafast Discharge and Improved Electrochemical Performances

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

Dai, Yang; Fang, Yuan; Cai, Sendan

2016-12-01

Among all primary lithium batteries, Li/CF x primary battery possesses the highest energy density of 2180 Wh kg -1. However, a key limitation is its poor rate capability because the cathode material CF x is intrinsically a poor electronic conductor. Here, we developed a so-called “doing subtraction” method to modify the pinecone shaped fluorinated mesocarbon microbead (F-MCMB). The modified fluorinated mesocarbon microbead (MF-MCMB), manifests the advantage of open-framed structure, possesses good electronic conductivity and removes transport barrier for lithium ions. Thus, high capacity performance and excellent rate capability without compromising capacity can be obtained. A capacity of 343 mAhg -1more » and a maximum power density of 54600 W kg -1 are realized at an ultrafast rate of 40 C (28A g -1). Additionally, the MF-MCMB cathode does not show any voltage delay even at 5C during the discharge, which is a remarkable improvement over the state-of-the-art CF xmaterials.« less

Death certification: an audit of practice entering the 21st century

PubMed Central

Swift, B; West, K

2002-01-01

Aims: Death certification, a legal duty of doctors, continues to be poorly performed despite Royal College recommendations and increased education at an undergraduate level. Therefore, the current performance of certifying doctors was audited within a large teaching hospital entering the new century. Methods: A total of 1000 completed certificate counterfoils were examined retrospectively for appropriateness of completion and the ability to construct a logical cause of death cascade. Results: Only 55% of certificates were completed to a minimally accepted standard, and many of these failed to provide relevant information to allow adequate ICD-10 coding. Nearly 10% were completed to a poor standard, being illogical or inappropriately completed. Conclusions: The results show no improvement in the state of certification. Possible interventions to improve outcomes are discussed; however, in light of a recent high profile legal case a current Home Office review of death certification may suggest the passing of statutory law to ensure accurate completion. PMID:11919211

Doctor performance assessment in daily practise: does it help doctors or not? A systematic review.

PubMed

Overeem, Karlijn; Faber, Marjan J; Arah, Onyebuchi A; Elwyn, Glyn; Lombarts, Kiki M J M H; Wollersheim, Hub C; Grol, Richard P T M

2007-11-01

Continuous assessment of individual performance of doctors is crucial for life-long learning and quality of care. Policy-makers and health educators should have good insights into the strengths and weaknesses of the methods available. The aim of this study was to systematically evaluate the feasibility of methods, the psychometric properties of instruments that are especially important for summative assessments, and the effectiveness of methods serving formative assessments used in routine practise to assess the performance of individual doctors. We searched the MEDLINE (1966-January 2006), PsychINFO (1972-January 2006), CINAHL (1982-January 2006), EMBASE (1980-January 2006) and Cochrane (1966-2006) databases for English language articles, and supplemented this with a hand-search of reference lists of relevant studies and bibliographies of review articles. Studies that aimed to assess the performance of individual doctors in routine practise were included. Two reviewers independently abstracted data regarding study design, setting and findings related to reliability, validity, feasibility and effectiveness using a standard data abstraction form. A total of 64 articles met our inclusion criteria. We observed 6 different methods of evaluating performance: simulated patients; video observation; direct observation; peer assessment; audit of medical records, and portfolio or appraisal. Peer assessment is the most feasible method in terms of costs and time. Little psychometric assessment of the instruments has been undertaken so far. Effectiveness of formative assessments is poorly studied. All systems but 2 rely on a single method to assess performance. There is substantial potential to assess performance of doctors in routine practise. The longterm impact and effectiveness of formative performance assessments on education and quality of care remains hardly known. Future research designs need to pay special attention to unmasking effectiveness in terms of performance improvement.

Potential role of maternal lineage in the thoroughbred breeding strategy.

PubMed

Lin, Xiang; Zhou, Shi; Wen, Li; Davie, Allan; Yao, Xinkui; Liu, Wujun; Zhang, Yong

2015-05-05

Many studies have focused on identifying the genes or single nucleotide polymorphisms associated with the athletic ability of thoroughbreds, but few have considered differences in maternal and paternal heritability of athletic ability. Herein, we report on our association study of career race performances of 675 Australian thoroughbreds with their pedigrees. Racing performance data (prize money per start) were collected from the Bloodhound database. The performance of all horses was categorised as either poor or elite athletic achievement. Then, 675 foals were divided by their parents' performance (elite or poor) into four groups: (1) elite dams and elite sires; (2) elite dams and poor sires; (3) poor dams and elite sires; and (4) poor dams and poor sires. The performance of foals was then compared between the four groups. The results show that the heritability of race performance between dams and foals (r = 0.141, P < 0.001) is much higher than that between sires and foals (r = 0.035, P = 0.366), and that this difference is statistically significant (P < 0.05). We also examined the effect of the child-bearing age of dams and sires on the ratio of elite foals. We found a strong correlation between the number of elite foals and dams' child-bearing age (r = -0.105, P < 0.001), with the ratio of elite offspring reaching a high level between a child-bearing age of 8 and 11 years (χ2 = 14.31, d.f. = 1, P < 0.001). These findings suggest that the maternal line may play an important role in the selective breeding of athletic performance in thoroughbreds.

Non-compliance to the continuous ambulatory peritoneal dialysis procedure increases the risk of peritonitis.

PubMed

Mawar, Shashi; Gupta, Sanjay; Mahajan, Sandeep

2012-08-01

Peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD) is the leading cause of technique failure. Information on the impact of non-compliance in performing CAPD exchange on peritonitis is limited. We aimed to find the prevalence of non-compliance to the CAPD procedure and its influence on the incidence of peritonitis. This observational study included 30 adult patients undergoing CAPD. The CAPD exchange procedure was observed at home and assessed as per the structured checklist and categorized into poor, average and good compliance. The compliance was correlated with the episodes of peritonitis in previous 1 year. The patients' mean age was 52 ± 13 years and the mean duration of CAPD was 2.1 ± 0.9 years. Only 16.5% of patients were good performers, while 67% were average performers, and 16.5% were poor performers. The technique skill was similar across all the steps of the procedure. The most common improperly performed steps were: not putting on a face mask in 68%, not flushing the tubing system in 60%, and not washing hands in 24%. Poor adherence to procedure was independent of age, gender, education and duration of dialysis. Ten episodes of peritonitis occurred in 5 patients over 1-year period. Peritonitis occurred in 60% of poor performers, whereas fully compliant patients had no peritonitis. Also 40% of the poorly compliant patients had multiple episodes of peritonitis. Poor compliance in performing the CAPD procedure is a modifiable risk factor for peritonitis. Adherence to recommended aseptic technique is the cornerstone of peritonitis prevention.

Perceptions of good medical practice in the NHS: a survey of senior health professionals.

PubMed

Hutchinson, A; Williams, M; Meadows, K; Barbour, R S; Jones, R

1999-12-01

To categorize senior health professionals' experience with poor medical practice in hospitals and in general practice, to describe perceptions which senior NHS staff have of good medical practice, and to describe how problems of poor medical practice are currently managed. A postal questionnaire survey. The questionnaire sought perceptions of good medical practice, asked participants to characterise deviations from good practice, and to describe experience with managing poor performance at the time of the introduction of the General Medical Council (GMC) performance procedures. A range of NHS settings in the UK: hospital trusts, health authorities/boards, local medical committees, community health councils. Senior health professionals involved in the management of medical professional performance. Perceptions of what constitutes good medical practice. Most respondents considered that persistent problems related to clinical practice (diagnosis, management, and outcome and prescribing) would require local management and, possibly, referral to the GMC performance procedures. Informal mechanisms, including informal discussion, education, training, and work shifting, were the most usual means of handling a doctor whose performance was poor. Many took a less serious view of deficiencies in performance on manner and attitude and communication, although consultation skills rather than technical skills comprised the greatest number of complaints about doctors. Senior NHS professionals seem reluctant to consider persistently poor consultation skills in the same critical light as they do persistently poor technical practice. These attitudes may need to change with the implementation of clinical governance and updated guidance from the GMC on what constitutes good medical practice.

Born Small for Gestational Age and Poor School Performance - How Small Is Too Small?

PubMed

Lindström, Linda; Wikström, Anna-Karin; Bergman, Eva; Lundgren, Maria

2017-01-01

To assess the relationship between severity of small for gestational age (SGA) and the risk of poor school performance, and to investigate whether adult stature modifies this risk. 1,088,980 Swedish children born at term between 1973 and 1988 were categorized into severe SGA (less than -3 standard deviations (SD) of expected birth weight), moderate SGA (-2.01 to -3 SD), mild SGA (-1.01 to -2 SD), and appropriate for gestational age (-1 to 0.99 SD). The risk of poor school performance at the time of graduation from compulsory school (grades <10th percentile) was calculated using unconditional logistic regression models and adjusted for socio-economic factors. In a sub-analysis, we stratified boys by adult stature, and adjusted for maternal but not paternal height. All SGA groups were significantly associated with an increased risk of poor school performance, with adjusted odds ratios and 95% confidence intervals ranging from 1.85 (1.65-2.07) for severe SGA to 1.25 (1.22-1.28) for mild SGA. In the sub-analysis, all birth weight groups were associated with an increased risk of poor school performance among boys with short stature compared to those with non-short stature. Mild SGA is associated with a significantly increased risk of poor school performance, and the risk increases with severity of SGA. Further, this risk diminishes after adequate catch-up growth. © 2017 S. Karger AG, Basel.

Prediction of brain-computer interface aptitude from individual brain structure

PubMed Central

Halder, S.; Varkuti, B.; Bogdan, M.; Kübler, A.; Rosenstiel, W.; Sitaram, R.; Birbaumer, N.

2013-01-01

Objective: Brain-computer interface (BCI) provide a non-muscular communication channel for patients with impairments of the motor system. A significant number of BCI users is unable to obtain voluntary control of a BCI-system in proper time. This makes methods that can be used to determine the aptitude of a user necessary. Methods: We hypothesized that integrity and connectivity of involved white matter connections may serve as a predictor of individual BCI-performance. Therefore, we analyzed structural data from anatomical scans and DTI of motor imagery BCI-users differentiated into high and low BCI-aptitude groups based on their overall performance. Results: Using a machine learning classification method we identified discriminating structural brain trait features and correlated the best features with a continuous measure of individual BCI-performance. Prediction of the aptitude group of each participant was possible with near perfect accuracy (one error). Conclusions: Tissue volumetric analysis yielded only poor classification results. In contrast, the structural integrity and myelination quality of deep white matter structures such as the Corpus Callosum, Cingulum, and Superior Fronto-Occipital Fascicle were positively correlated with individual BCI-performance. Significance: This confirms that structural brain traits contribute to individual performance in BCI use. PMID:23565083

An Evaluation of the Performance Diagnostic Checklist-Human Services to Assess an Employee Performance Problem in a Center-Based Autism Treatment Facility

ERIC Educational Resources Information Center

Ditzian, Kyle; Wilder, David A.; King, Allison; Tanz, Jeanine

2015-01-01

The Performance Diagnostic Checklist-Human Services (PDC-HS) is an informant-based tool designed to assess the environmental variables that contribute to poor employee performance in human services settings. We administered the PDC-HS to 3 supervisors to assess the variables that contributed to poor performance by 4 staff members when securing…

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…

Improved scintillation detector performance via a method of enhanced layered coatings

DOE PAGES

Wakeford, Daniel Tyler; Tornga, Shawn Robert; Adams, Jillian Cathleen; ...

2016-11-16

Increasing demand for better detection performance with a simultaneous reduction in size, weight and power consumption has motivated the use of compact semiconductors as photo-converters for many gamma-ray and neutron scintillators. The spectral response of devices such as silicon avalanche photodiodes (APDs) is poorly matched to many common high-performance scintillators. We have developed a generalized analytical method that utilizes an optical reference database to match scintillator luminescence to the excitation spectrum of high quantum efficiency semiconductor detectors. This is accomplished by the fabrication and application of a series of high quantum yield, short fluorescence lifetime, wavelengthshifting coatings. Furthermore, we showmore » here a 22% increase in photoelectron collection and a 10% improvement in energy resolution when applying a layered coating to an APD-coupled, cerium-doped, yttrium oxyorthosilicate (YSO:Ce) scintillator. Wavelength-shifted radioluminescence emission and rise time analysis are also discussed.« less

Examination of diagnostic features in multiphoton microscopy and optical coherence tomography images of ovarian tumorigenesis in a mouse model

NASA Astrophysics Data System (ADS)

Watson, Jennifer M.

Ovarian cancer is a deadly disease owing to the non-specific symptoms and suspected rapid progression, leading to frequent late stage detection and poor prognosis. Medical imaging methods such as CT, MRI and ultrasound as well as serum testing for cancer markers have had extremely poor performance for early disease detection. Due to the poor performance of available screening methods, and the impracticality and ineffectiveness of taking tissue biopsies from the ovary, women at high risk for developing ovarian cancer are often advised to undergo prophylactic salpingo-oophorectomy. This surgery results in many side effects and is most often unnecessary since only a fraction of high risk women go on to develop ovarian cancer. Better understanding of the early development of ovarian cancer and characterization of morphological changes associated with early disease could lead to the development of an effective screening test for women at high risk. Optical imaging methods including optical coherence tomography (OCT) and multiphoton microscopy (MPM) are excellent tools for studying disease progression owing to the high resolution and depth sectioning capabilities. Further, these techniques are excellent for optical biopsy because they can image in situ non-destructively. In the studies described in this dissertation OCT and MPM are used to identify cellular and tissue morphological changes associated with early tumor development in a mouse model of ovarian cancer. This work is organized into three specific aims. The first aim is to use the images from the MPM phenomenon of second harmonic generation to quantitatively examine the morphological differences in collagen structure in normal mouse ovarian tissue and mouse ovarian tumors. The second aim is to examine the differences in endogenous two-photon excited fluorescence in normal mouse ovarian tissue and mouse ovarian tumors. The third and final aim is to identify changes in ovarian microstructure resulting from early disease development by imaging animals in vivo at three time points during a long-term survival study.

Review of Methods for Buildings Energy Performance Modelling

NASA Astrophysics Data System (ADS)

Krstić, Hrvoje; Teni, Mihaela

2017-10-01

Research presented in this paper gives a brief review of methods used for buildings energy performance modelling. This paper gives also a comprehensive review of the advantages and disadvantages of available methods as well as the input parameters used for modelling buildings energy performance. European Directive EPBD obliges the implementation of energy certification procedure which gives an insight on buildings energy performance via exiting energy certificate databases. Some of the methods for buildings energy performance modelling mentioned in this paper are developed by employing data sets of buildings which have already undergone an energy certification procedure. Such database is used in this paper where the majority of buildings in the database have already gone under some form of partial retrofitting - replacement of windows or installation of thermal insulation but still have poor energy performance. The case study presented in this paper utilizes energy certificates database obtained from residential units in Croatia (over 400 buildings) in order to determine the dependence between buildings energy performance and variables from database by using statistical dependencies tests. Building energy performance in database is presented with building energy efficiency rate (from A+ to G) which is based on specific annual energy needs for heating for referential climatic data [kWh/(m2a)]. Independent variables in database are surfaces and volume of the conditioned part of the building, building shape factor, energy used for heating, CO2 emission, building age and year of reconstruction. Research results presented in this paper give an insight in possibilities of methods used for buildings energy performance modelling. Further on it gives an analysis of dependencies between buildings energy performance as a dependent variable and independent variables from the database. Presented results could be used for development of new building energy performance predictive model.

The Effect of a Self-Cueing Treatment on Top-Level Goal Setting Strategies and Attention to Task in Timed-Writing Sessions.

ERIC Educational Resources Information Center

Hindman, JaneE

A case study examined one college student's poor performances during timed-writing sessions to develop a method to allow students to maintain the quality and ease in writing they achieve in other writing situations. The student, assigned to write a movie review, volunteered to participate in two 90 minute talk-aloud protocol sessions to examine…

Improving regression-model-based streamwater constituent load estimates derived from serially correlated data

USGS Publications Warehouse

Aulenbach, Brent T.

2013-01-01

A regression-model based approach is a commonly used, efficient method for estimating streamwater constituent load when there is a relationship between streamwater constituent concentration and continuous variables such as streamwater discharge, season and time. A subsetting experiment using a 30-year dataset of daily suspended sediment observations from the Mississippi River at Thebes, Illinois, was performed to determine optimal sampling frequency, model calibration period length, and regression model methodology, as well as to determine the effect of serial correlation of model residuals on load estimate precision. Two regression-based methods were used to estimate streamwater loads, the Adjusted Maximum Likelihood Estimator (AMLE), and the composite method, a hybrid load estimation approach. While both methods accurately and precisely estimated loads at the model’s calibration period time scale, precisions were progressively worse at shorter reporting periods, from annually to monthly. Serial correlation in model residuals resulted in observed AMLE precision to be significantly worse than the model calculated standard errors of prediction. The composite method effectively improved upon AMLE loads for shorter reporting periods, but required a sampling interval of at least 15-days or shorter, when the serial correlations in the observed load residuals were greater than 0.15. AMLE precision was better at shorter sampling intervals and when using the shortest model calibration periods, such that the regression models better fit the temporal changes in the concentration–discharge relationship. The models with the largest errors typically had poor high flow sampling coverage resulting in unrepresentative models. Increasing sampling frequency and/or targeted high flow sampling are more efficient approaches to ensure sufficient sampling and to avoid poorly performing models, than increasing calibration period length.

Manual versus Automated Carotid Artery Plaque Component Segmentation in High and Lower Quality 3.0 Tesla MRI Scans

PubMed Central

Smits, Loek P.; van Wijk, Diederik F.; Duivenvoorden, Raphael; Xu, Dongxiang; Yuan, Chun; Stroes, Erik S.; Nederveen, Aart J.

2016-01-01

Purpose To study the interscan reproducibility of manual versus automated segmentation of carotid artery plaque components, and the agreement between both methods, in high and lower quality MRI scans. Methods 24 patients with 30–70% carotid artery stenosis were planned for 3T carotid MRI, followed by a rescan within 1 month. A multicontrast protocol (T1w,T2w, PDw and TOF sequences) was used. After co-registration and delineation of the lumen and outer wall, segmentation of plaque components (lipid-rich necrotic cores (LRNC) and calcifications) was performed both manually and automated. Scan quality was assessed using a visual quality scale. Results Agreement for the detection of LRNC (Cohen’s kappa (k) is 0.04) and calcification (k = 0.41) between both manual and automated segmentation methods was poor. In the high-quality scans (visual quality score ≥ 3), the agreement between manual and automated segmentation increased to k = 0.55 and k = 0.58 for, respectively, the detection of LRNC and calcification larger than 1 mm2. Both manual and automated analysis showed good interscan reproducibility for the quantification of LRNC (intraclass correlation coefficient (ICC) of 0.94 and 0.80 respectively) and calcified plaque area (ICC of 0.95 and 0.77, respectively). Conclusion Agreement between manual and automated segmentation of LRNC and calcifications was poor, despite a good interscan reproducibility of both methods. The agreement between both methods increased to moderate in high quality scans. These findings indicate that image quality is a critical determinant of the performance of both manual and automated segmentation of carotid artery plaque components. PMID:27930665

Health System Competency for Maternal Health Services in Balasore District and Jaleswar Block, Balasore, Odisha, India: An Assessment

PubMed Central

Samal, Janmejaya

2016-01-01

Introduction A competent health system is of paramount importance in delivering the desired health services in a particular community. Aim The broad objective of this study was to assess the health system competency for the maternal health services in Balasore District and Jaleswar block of Balasore district, Odisha, India. Materials and Methods A mixed method approach was adopted in order to understand the health system competency for maternal health services in the study area. Results There was poor accessibility through road, poor electricity connection and piped water for the health care centers in the district. Even, existing Primary Health Centres (PHCs) lack ECG and X-Ray machines for proper diagnostic services which jeopardize the catering of health services. Community Health Centres (CHC) lack basic diagnostic and ambulance services making the tribal pockets inaccessible. The tribal dominated Jaleswar block shows poor performance in terms of total registered Antenatal Checkups (ANC) (only 77%). A gradual decrease in the rate of ANC, from first to fourthcheckup, was observed in the district. Conclusion Lack of public health infrastructure in general and non-compliance to Indian Public Health Standards (IPHS) in particular, affect the health of tribal women resulting in lack of interest in availing the institutional delivery services and other pertinent maternal health services. PMID:27656464

20 CFR 632.23 - Termination and corrective action of a CAP and/or Master Plan.

Code of Federal Regulations, 2010 CFR

2010-04-01

... substantiates serious management, fiscal and/or performance problems, information from the Inspector General or gained through incident reports of poor performance, serious administrative problems and/or inability to... termination: (1) Poor performance and inability to meet Federal standards related to such debt collection...

Ensemble analyses improve signatures of tumour hypoxia and reveal inter-platform differences

PubMed Central

2014-01-01

Background The reproducibility of transcriptomic biomarkers across datasets remains poor, limiting clinical application. We and others have suggested that this is in-part caused by differential error-structure between datasets, and their incomplete removal by pre-processing algorithms. Methods To test this hypothesis, we systematically assessed the effects of pre-processing on biomarker classification using 24 different pre-processing methods and 15 distinct signatures of tumour hypoxia in 10 datasets (2,143 patients). Results We confirm strong pre-processing effects for all datasets and signatures, and find that these differ between microarray versions. Importantly, exploiting different pre-processing techniques in an ensemble technique improved classification for a majority of signatures. Conclusions Assessing biomarkers using an ensemble of pre-processing techniques shows clear value across multiple diseases, datasets and biomarkers. Importantly, ensemble classification improves biomarkers with initially good results but does not result in spuriously improved performance for poor biomarkers. While further research is required, this approach has the potential to become a standard for transcriptomic biomarkers. PMID:24902696

The application of quantitative methods for identifying and exploring the presence of bias in systematic reviews: PDE-5 inhibitors for erectile dysfunction.

PubMed

Bekkering, G E; Abou-Setta, A M; Kleijnen, J

2008-01-01

A systematic review of PDE-5 inhibitors for erectile dysfunction was performed to evaluate the utility of quantitative methods for identifying and exploring the influence of bias and study quality on pooled outcomes from meta-analyses. We included 123 randomized controlled trials (RCTs). Methodological quality was poorly reported. All three drugs appeared highly effective. Indirect adjusted analyses showed no differences between the three drugs. Funnel plots and statistical tests showed no evidence of small-study effects for sildenafil whereas there was evidence of such bias for tadalafil and vardenafil. Adjustment for missing studies using trim and fill techniques did not alter the pooled estimates substantially. The exclusion of previous sildenafil nonresponders was associated with larger treatment effects for tadalafil. This investigation was hampered by poor reporting of methodological quality, a low number of studies, heterogeneity and large effect sizes. Despite such limitations, a comprehensive assessment of biases should be a routine in systematic reviews.

Single-channel EEG-based mental fatigue detection based on deep belief network.

PubMed

Pinyi Li; Wenhui Jiang; Fei Su

2016-08-01

Mental fatigue has a pernicious influence on road and work place safety as well as a negative symptom of many acute and chronic illnesses, since the ability of concentrating, responding and judging quickly decreases during the fatigue or drowsiness stage. Electroencephalography (EEG) has been proven to be a robust physiological indicator of human cognitive state over the last few decades. But most existing EEG-based fatigue detection methods have poor performance in accuracy. This paper proposed a single-channel EEG-based mental fatigue detection method based on Deep Belief Network (DBN). The fused nonliear features from specified sub-bands and dynamic analysis, a total of 21 features are extracted as the input of the DBN to discriminate three classes of mental state including alert, slight fatigue and severe fatigue. Experimental results show the good performance of the proposed model comparing with those state-of-art methods.

Not self-focused attention but negative beliefs affect poor social performance in social anxiety: an investigation of pathways in the social anxiety-social rejection relationship.

PubMed

Voncken, Marisol J; Dijk, Corine; de Jong, Peter J; Roelofs, Jeffrey

2010-10-01

Patients with social anxiety disorder (SAD) not only fear negative evaluation but are indeed less likeable than people without SAD. Previous research shows social performance to mediate this social anxiety-social rejection relationship. This study studied two pathways hypothesized to lead to poor social performance in social anxiety: increased self-focused attention and negative beliefs. State social anxiety was experimentally manipulated in high and low-blushing-fearful individuals by letting half of the participants believe that they blushed intensely during a 5 min getting-acquainted interaction with two confederates. Participants rated their state social anxiety, self-focused attention, and level of negative beliefs. Two confederates and two video-observers rated subsequently likeability (i.e., social rejection) and social performance of the participants. In both groups, the social anxiety-social rejection relationship was present. Although state social anxiety was related to heightened self-focused attention and negative beliefs, only negative beliefs were associated with relatively poor social performance. In contrast to current SAD models, self-focused attention did not play a key-role in poor social performance but seemed to function as a by-product of state social anxiety. Beliefs of being negatively evaluated seem to elicit changes in behavioral repertoire resulting in a poor social performance and subsequent rejection. Copyright 2010 Elsevier Ltd. All rights reserved.

Sleep problems are associated with poor outcomes in remedial teaching programmes: a preliminary study.

PubMed

Blunden, Sarah L; Chervin, Ron D

2008-05-01

Problematic behaviour and deficient academic performance have been reported in children with sleep problems, but whether sleep problems are common among children presenting with primary behavioural and performance concerns in remedial programmes is not well studied. We studied this possibility in 80 Australian school children aged 6-15 years and then compared 15 of these children from mainstream schools to 15 demographically matched children in specialist behavioural programmes for problematic behaviour and academic difficulties. Parents completed the Child Behaviour Checklist and the Sleep Disorders Scale for Children. Questionnaires assessed behaviour, academic performance and symptoms of diverse sleep disorders, expressed as T-scores (mean (SD) = 50 (10)). Teachers rated students' academic performance (A, B, C, D, E). When compared with the 15 controls, the 15 index children had significantly more sleep problems, in addition to parental concerns about school performance. In the total sample (n = 80), poor sleep including symptoms of daytime sleepiness, parasomnias, behavioural sleep problems and combined sleep problems was associated with poor academic performance and daytime behavioural issues. This preliminary study suggests that children in remedial school programmes may have poor sleep compared with those in mainstream schools. Sleep problems were associated with problematic behaviour and poor academic performance. If sleep disturbances worsen daytime behaviour, then diagnosis and treatment of underlying sleep disorders could offer a novel therapeutic opportunity.

Educational attainment in poor comprehenders

PubMed Central

Ricketts, Jessie; Sperring, Rachael; Nation, Kate

2014-01-01

To date, only one study has investigated educational attainment in poor (reading) comprehenders, providing evidence of poor performance on national UK school tests at age 11 years relative to peers (Cain and Oakhill, 2006). In the present study, we adopted a longitudinal approach, tracking attainment on such tests from 11 years to the end of compulsory schooling in the UK (age 16 years). We aimed to investigate the proposal that educational weaknesses (defined as poor performance on national assessments) might become more pronounced over time, as the curriculum places increasing demands on reading comprehension. Participants comprised 15 poor comprehenders and 15 controls; groups were matched for chronological age, nonverbal reasoning ability and decoding skill. Children were identified at age 9 years using standardized measures of nonverbal reasoning, decoding and reading comprehension. These measures, along with a measure of oral vocabulary knowledge, were repeated at age 11 years. Data on educational attainment were collected from all participants (n = 30) at age 11 and from a subgroup (n = 21) at 16 years. Compared to controls, educational attainment in poor comprehenders was lower at ages 11 and 16 years, an effect that was significant at 11 years. When poor comprehenders were compared to national performance levels, they showed significantly lower performance at both time points. Low educational attainment was not evident for all poor comprehenders. Nonetheless, our findings point to a link between reading comprehension difficulties in mid to late childhood and poor educational outcomes at ages 11 and 16 years. At these ages, pupils in the UK are making key transitions: they move from primary to secondary schools at 11, and out of compulsory schooling at 16. PMID:24904464

Association between Self-Reported Academic Performance and Risky Sexual Behavior among Ugandan University Students- A Cross Sectional Study

PubMed Central

Mehra, Devika; Kyagaba, Emmanuel; Östergren, Per-Olof; Agardh, Anette

2014-01-01

Little is known about the association between self-reported academic performance and risky sexual behaviors and if this differs by gender, among university students. Academic performance can create psychological pressure in young students. Poor academic performance might thus potentially contribute to risky sexual behavior among university students. The aim of this study was to investigate the association between self-reported academic performance and risky sexual behaviors, and whether gender affects this relationship among Ugandan university students. In 2010, 1,954 students participated in a cross-sectional survey, conducted at Mbarara University of Science and Technology in southwestern Uganda (72% response rate). Multivariate logistic regression analysis was used for the analysis. 1,179 (60.3%) students in our study sample reported having debuted sexually. Of these 440 (42.2%) used condoms inconsistently with new sexual partners, and 344 (33.6%) had had multiple sexual partners. We found a statistically significant association between poor academic performance and inconsistent condom use with a new sex partner and this association remained significant even after adjusting for all the potential confounders. There was no such association detected regarding multiple sexual partners. We also found that gender modified the effect of poor academic performance on inconsistent condom use. Females, who were poor academic performers, were found to be at a higher risk of inconsistent condom use than their male counterparts. Interventions should be designed to provide extra support to poor academic performers, which may improve their performance and self-esteem, which in turn might reduce their risky sexual behaviors. PMID:24999121

Association between self-reported academic performance and risky sexual behavior among Ugandan university students- a cross sectional study.

PubMed

Mehra, Devika; Kyagaba, Emmanuel; Ostergren, Per-Olof; Agardh, Anette

2014-04-16

Little is known about the association between self-reported academic performance and risky sexual behaviors and if this differs by gender, among university students. Academic performance can create psychological pressure in young students. Poor academic performance might thus potentially contribute to risky sexual behavior among university students. The aim of this study was to investigate the association between self-reported academic performance and risky sexual behaviors, and whether gender affects this relationship among Ugandan university students. In 2010, 1,954 students participated in a cross-sectional survey, conducted at Mbarara University of Science and Technology in southwestern Uganda (72% response rate). Multivariate logistic regression analysis was used for the analysis. 1,179 (60.3%) students in our study sample reported having debuted sexually. Of these 440 (42.2%) used condoms inconsistently with new sexual partners, and 344 (33.6%) had had multiple sexual partners. We found a statistically significant association between poor academic performance and inconsistent condom use with a new sex partner and this association remained significant even after adjusting for all the potential confounders. There was no such association detected regarding multiple sexual partners. We also found that gender modified the effect of poor academic performance on inconsistent condom use. Females, who were poor academic performers, were found to be at a higher risk of inconsistent condom use than their male counterparts. Interventions should be designed to provide extra support to poor academic performers, which may improve their performance and self-esteem, which in turn might reduce their risky sexual behaviors.

Cognitive control components and speech symptoms in people with schizophrenia.

PubMed

Becker, Theresa M; Cicero, David C; Cowan, Nelson; Kerns, John G

2012-03-30

Previous schizophrenia research suggests poor cognitive control is associated with schizophrenia speech symptoms. However, cognitive control is a broad construct. Two important cognitive control components are poor goal maintenance and poor verbal working memory storage. In the current research, people with schizophrenia (n=45) performed three cognitive tasks that varied in their goal maintenance and verbal working memory storage demands. Speech symptoms were assessed using clinical rating scales, ratings of disorganized speech from typed transcripts, and self-reported disorganization. Overall, alogia was associated with both goal maintenance and verbal working memory tasks. Objectively rated disorganized speech was associated with poor goal maintenance and with a task that included both goal maintenance and verbal working memory storage demands. In contrast, self-reported disorganization was unrelated to either amount of objectively rated disorganized speech or to cognitive control task performance, instead being associated with negative mood symptoms. Overall, our results suggest that alogia is associated with both poor goal maintenance and poor verbal working memory storage and that disorganized speech is associated with poor goal maintenance. In addition, patients' own assessment of their disorganization is related to negative mood, but perhaps not to objective disorganized speech or to cognitive control task performance. Published by Elsevier Ireland Ltd.

Operative management of penetrating carotid artery injuries.

PubMed

Reva, V A; Pronchenko, A A; Samokhvalov, I M

2011-07-01

To analyse management and outcomes of carotid artery (CA) injuries. Retrospective study of the patients in the combat operations in Chechnya (1999-2002) and in peacetime (2003-2009). A total of 46 patients with missile (27) and stab (19) wounds, who had common and internal CA injury, underwent an open surgery. Temporary shunts (TSs) were placed in eight patients with more severe injuries. Retrospective analysis of patients' data. CA ligation and CA repair were performed in 9 and 37 patients, respectively. Of the nine patients with CA ligation, five developed neurologic deficit; the remaining four patients died (100% of poor outcomes). Of the 37 patients with blood flow restoration, nine patients died and neurologic deficit persisted in two patients (30% of poor outcomes) (p < 0.05). Among patients with TS, three patients died and two had stable neurologic deficit (63% of poor results). Of the patients without TS, 10 patients died and five had neurologic disorders (56% of poor outcomes) (p = 0.53). CA repair is the method of choice in CA injury. TS use does not result in a decreased mortality rate or neurologic deficit reduction in patients with severe injuries. Copyright © 2011 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

A Tiered Analytical Approach for Investigating Poor Quality Emergency Contraceptives

PubMed Central

Monge, María Eugenia; Dwivedi, Prabha; Zhou, Manshui; Payne, Michael; Harris, Chris; House, Blaine; Juggins, Yvonne; Cizmarik, Peter; Newton, Paul N.; Fernández, Facundo M.; Jenkins, David

2014-01-01

Reproductive health has been deleteriously affected by poor quality medicines. Emergency contraceptive pills (ECPs) are an important birth control method that women can use after unprotected coitus for reducing the risk of pregnancy. In response to the detection of poor quality ECPs commercially available in the Peruvian market we developed a tiered multi-platform analytical strategy. In a survey to assess ECP medicine quality in Peru, 7 out of 25 different batches showed inadequate release of levonorgestrel by dissolution testing or improper amounts of active ingredient. One batch was found to contain a wrong active ingredient, with no detectable levonorgestrel. By combining ultrahigh performance liquid chromatography-ion mobility spectrometry-mass spectrometry (UHPLC-IMS-MS) and direct analysis in real time MS (DART-MS) the unknown compound was identified as the antibiotic sulfamethoxazole. Quantitation by UHPLC-triple quadrupole tandem MS (QqQ-MS/MS) indicated that the wrong ingredient was present in the ECP sample at levels which could have significant physiological effects. Further chemical characterization of the poor quality ECP samples included the identification of the excipients by 2D Diffusion-Ordered Nuclear Magnetic Resonance Spectroscopy (DOSY 1H NMR) indicating the presence of lactose and magnesium stearate. PMID:24748219

Encoding of speech sounds at auditory brainstem level in good and poor hearing aid performers.

PubMed

Shetty, Hemanth Narayan; Puttabasappa, Manjula

Hearing aids are prescribed to alleviate loss of audibility. It has been reported that about 31% of hearing aid users reject their own hearing aid because of annoyance towards background noise. The reason for dissatisfaction can be located anywhere from the hearing aid microphone till the integrity of neurons along the auditory pathway. To measure spectra from the output of hearing aid at the ear canal level and frequency following response recorded at the auditory brainstem from individuals with hearing impairment. A total of sixty participants having moderate sensorineural hearing impairment with age range from 15 to 65 years were involved. Each participant was classified as either Good or Poor Hearing aid Performers based on acceptable noise level measure. Stimuli /da/ and /si/ were presented through loudspeaker at 65dB SPL. At the ear canal, the spectra were measured in the unaided and aided conditions. At auditory brainstem, frequency following response were recorded to the same stimuli from the participants. Spectrum measured in each condition at ear canal was same in good hearing aid performers and poor hearing aid performers. At brainstem level, better F 0 encoding; F 0 and F 1 energies were significantly higher in good hearing aid performers than in poor hearing aid performers. Though the hearing aid spectra were almost same between good hearing aid performers and poor hearing aid performers, subtle physiological variations exist at the auditory brainstem. The result of the present study suggests that neural encoding of speech sound at the brainstem level might be mediated distinctly in good hearing aid performers from that of poor hearing aid performers. Thus, it can be inferred that subtle physiological changes are evident at the auditory brainstem in a person who is willing to accept noise from those who are not willing to accept noise. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

The performance of community health workers in the management of multiple childhood infectious diseases in Lira, northern Uganda - a mixed methods cross-sectional study.

PubMed

Wanduru, Phillip; Tetui, Moses; Tuhebwe, Doreen; Ediau, Michael; Okuga, Monica; Nalwadda, Christine; Ekirapa-Kiracho, Elizabeth; Waiswa, Peter; Rutebemberwa, Elizeus

2016-01-01

Community health workers (CHWs) have the potential to reduce child mortality by improving access to care, especially in remote areas. Uganda has one of the highest child mortality rates globally. Moreover, rural areas bear the highest proportion of this burden. The optimal performance of CHWs is critical. In this study, we assess the performance of CHWs in managing malaria, pneumonia, and diarrhea in the rural district of Lira, in northern Uganda. A cross-sectional mixed methods study was undertaken to investigate the performance of 393 eligible CHWs in the Lira district of Uganda. Case scenarios were conducted with a medical officer observing CHWs in their management of children suspected of having malaria, pneumonia, or diarrhea. Performance data were collected using a pretested questionnaire with a checklist used by the medical officer to score the CHWs. The primary outcome, CHW performance, is defined as the ability to diagnose and treat malaria, diarrhea, and pneumonia appropriately. Participants were described using a three group performance score (good vs. moderate vs. poor). A binary measure of performance (good vs. poor) was used in multivariable logistic regression to show an association between good performance and a range of independent variables. The qualitative component comprised seven key informant interviews with experts who had informed knowledge with regard to the functionality of CHWs in Lira district. Overall, 347 CHWs (88.3%) had poor scores in managing malaria, diarrhea, and pneumonia, 26 (6.6%) had moderate scores, and 20 (5.1%) had good scores. The factors that were positively associated with performance were secondary-level education (adjusted odds ratio [AOR] 2.72; 95% confidence interval [CI] 1.50-4.92) and meeting with supervisors in the previous month (AOR 2.52; 95% CI 1.12-5.70). Those factors negatively associated with CHW performance included: serving 100-200 households (AOR 0.24; 95% CI 0.12-0.50), serving more than 200 households (AOR 0.22; 95% CI 0.10-0.48), and an initial training duration lasting 2-3 days (AOR 0.13; 95% CI 0.04-0.41). The qualitative findings reinforced the quantitative results by indicating that refresher training, workload, and in-kind incentives were important determinants of performance. The performance of CHWs in Lira was inadequate. There is a need to consider pre-qualification testing before CHWs are appointed. Providing ongoing support and supervision, and ensuring that CHWs have at least secondary education can be helpful in improving their performance. Health system managers also need to ensure that the CHWs' workload is moderated as work overload will reduce performance. Finally, although short training programs are beneficial to some degree, they are not sufficient and should be followed up with regular refresher training.

Persistent Postconcussive Symptoms Are Accompanied by Decreased Functional Brain Oxygenation.

PubMed

Helmich, Ingo; Saluja, Rajeet S; Lausberg, Hedda; Kempe, Mathias; Furley, Philip; Berger, Alisa; Chen, Jen-Kai; Ptito, Alain

2015-01-01

Diagnostic methods are considered a major concern in the determination of mild traumatic brain injury. The authors examined brain oxygenation patterns in subjects with severe and minor persistent postconcussive difficulties and a healthy control group during working memory tasks in prefrontal brain regions using functional near-infrared spectroscopy. The results demonstrated decreased working memory performances among concussed subjects with severe postconcussive symptoms that were accompanied by decreased brain oxygenation patterns. An association appears to exist between decreased brain oxygenation, poor performance of working memory tasks, and increased symptom severity scores in subjects suffering from persistent postconcussive symptoms.

[100]-Oriented LiFePO4 Nanoflakes toward High Rate Li-Ion Battery Cathode.

PubMed

Li, Zhaojin; Peng, Zhenzhen; Zhang, Hui; Hu, Tao; Hu, Minmin; Zhu, Kongjun; Wang, Xiaohui

2016-01-13

[100] is believed to be a tough diffusion direction for Li(+) in LiFePO4, leading to the belief that the rate performance of [100]-oriented LiFePO4 is poor. Here we report the fabrication of 12 nm-thick [100]-oriented LiFePO4 nanoflakes by a simple one-pot solvothermal method. The nanoflakes exhibit unexpectedly excellent electrochemical performance, in stark contrast to what was previously believed. Such an exceptional result is attributed to a decreased thermodynamic transformation barrier height (Δμb) associated with increased active population.

An adaptive optics imaging system designed for clinical use.

PubMed

Zhang, Jie; Yang, Qiang; Saito, Kenichi; Nozato, Koji; Williams, David R; Rossi, Ethan A

2015-06-01

Here we demonstrate a new imaging system that addresses several major problems limiting the clinical utility of conventional adaptive optics scanning light ophthalmoscopy (AOSLO), including its small field of view (FOV), reliance on patient fixation for targeting imaging, and substantial post-processing time. We previously showed an efficient image based eye tracking method for real-time optical stabilization and image registration in AOSLO. However, in patients with poor fixation, eye motion causes the FOV to drift substantially, causing this approach to fail. We solve that problem here by tracking eye motion at multiple spatial scales simultaneously by optically and electronically integrating a wide FOV SLO (WFSLO) with an AOSLO. This multi-scale approach, implemented with fast tip/tilt mirrors, has a large stabilization range of ± 5.6°. Our method consists of three stages implemented in parallel: 1) coarse optical stabilization driven by a WFSLO image, 2) fine optical stabilization driven by an AOSLO image, and 3) sub-pixel digital registration of the AOSLO image. We evaluated system performance in normal eyes and diseased eyes with poor fixation. Residual image motion with incremental compensation after each stage was: 1) ~2-3 arc minutes, (arcmin) 2) ~0.5-0.8 arcmin and, 3) ~0.05-0.07 arcmin, for normal eyes. Performance in eyes with poor fixation was: 1) ~3-5 arcmin, 2) ~0.7-1.1 arcmin and 3) ~0.07-0.14 arcmin. We demonstrate that this system is capable of reducing image motion by a factor of ~400, on average. This new optical design provides additional benefits for clinical imaging, including a steering subsystem for AOSLO that can be guided by the WFSLO to target specific regions of interest such as retinal pathology and real-time averaging of registered images to eliminate image post-processing.

A Longitudinal Examination of the Persistence of Late Emerging Reading Disabilities.

PubMed

Etmanskie, Jill M; Partanen, Marita; Siegel, Linda S

2016-01-01

There are some children who encounter unexpected reading difficulties in the fourth grade. This phenomenon has been described as late emerging reading disabilities (LERD). Using Grade 4 as a starting point, this study examined the reading development of 964 children between kindergarten and Grade 7. The results showed that 72.0% of children had typical reading performance in Grade 4, whereas there was 0.7% with poor word reading, 12.6% with poor reading comprehension, 2.5% with poor word reading and comprehension, and 12.2% with borderline performance. We also showed that there were similar proportions of children who had early versus late emerging reading difficulties; however, most of the late emerging poor readers recovered by Grade 7. Furthermore, our study showed that poor comprehenders showed poorer performance than typical readers on word reading, pseudoword decoding, and spelling between Grade 1 and Grade 7 and poorer performance on a working memory task in kindergarten. Overall, this study showed that most children recover from late emerging reading problems and that working memory may be an early indicator for reading comprehension difficulties. © Hammill Institute on Disabilities 2014.

Mapping species distributions with MAXENT using a geographically biased sample of presence data: a performance assessment of methods for correcting sampling bias.

PubMed

Fourcade, Yoan; Engler, Jan O; Rödder, Dennis; Secondi, Jean

2014-01-01

MAXENT is now a common species distribution modeling (SDM) tool used by conservation practitioners for predicting the distribution of a species from a set of records and environmental predictors. However, datasets of species occurrence used to train the model are often biased in the geographical space because of unequal sampling effort across the study area. This bias may be a source of strong inaccuracy in the resulting model and could lead to incorrect predictions. Although a number of sampling bias correction methods have been proposed, there is no consensual guideline to account for it. We compared here the performance of five methods of bias correction on three datasets of species occurrence: one "virtual" derived from a land cover map, and two actual datasets for a turtle (Chrysemys picta) and a salamander (Plethodon cylindraceus). We subjected these datasets to four types of sampling biases corresponding to potential types of empirical biases. We applied five correction methods to the biased samples and compared the outputs of distribution models to unbiased datasets to assess the overall correction performance of each method. The results revealed that the ability of methods to correct the initial sampling bias varied greatly depending on bias type, bias intensity and species. However, the simple systematic sampling of records consistently ranked among the best performing across the range of conditions tested, whereas other methods performed more poorly in most cases. The strong effect of initial conditions on correction performance highlights the need for further research to develop a step-by-step guideline to account for sampling bias. However, this method seems to be the most efficient in correcting sampling bias and should be advised in most cases.

Mapping Species Distributions with MAXENT Using a Geographically Biased Sample of Presence Data: A Performance Assessment of Methods for Correcting Sampling Bias

PubMed Central

Fourcade, Yoan; Engler, Jan O.; Rödder, Dennis; Secondi, Jean

2014-01-01

MAXENT is now a common species distribution modeling (SDM) tool used by conservation practitioners for predicting the distribution of a species from a set of records and environmental predictors. However, datasets of species occurrence used to train the model are often biased in the geographical space because of unequal sampling effort across the study area. This bias may be a source of strong inaccuracy in the resulting model and could lead to incorrect predictions. Although a number of sampling bias correction methods have been proposed, there is no consensual guideline to account for it. We compared here the performance of five methods of bias correction on three datasets of species occurrence: one “virtual” derived from a land cover map, and two actual datasets for a turtle (Chrysemys picta) and a salamander (Plethodon cylindraceus). We subjected these datasets to four types of sampling biases corresponding to potential types of empirical biases. We applied five correction methods to the biased samples and compared the outputs of distribution models to unbiased datasets to assess the overall correction performance of each method. The results revealed that the ability of methods to correct the initial sampling bias varied greatly depending on bias type, bias intensity and species. However, the simple systematic sampling of records consistently ranked among the best performing across the range of conditions tested, whereas other methods performed more poorly in most cases. The strong effect of initial conditions on correction performance highlights the need for further research to develop a step-by-step guideline to account for sampling bias. However, this method seems to be the most efficient in correcting sampling bias and should be advised in most cases. PMID:24818607

Evaluation of Mental Workload among ICU Ward's Nurses

PubMed Central

Mohammadi, Mohsen; Mazloumi, Adel; Kazemi, Zeinab; Zeraati, Hojat

2015-01-01

Background: High level of workload has been identified among stressors of nurses in intensive care units (ICUs). The present study investigated nursing workload and identified its influencing perfor­mance obstacles in ICUs. Methods: This cross-sectional study was conducted, in 2013, on 81 nurses working in ICUs in Imam Khomeini Hospital in Tehran, Iran. NASA-TLX was applied for assessment of workload. Moreover, ICUs Performance Obstacles Questionnaire was used to identify performance obstacles associated with ICU nursing. Results: Physical demand (mean=84.17) was perceived as the most important dimensions of workload by nurses. The most critical performance obstacles affecting workload included: difficulty in finding a place to sit down, hectic workplace, disorganized workplace, poor-conditioned equipment, waiting for using a piece of equipment, spending much time seeking for supplies in the central stock, poor quality of medical materials, delay in getting medications, unpredicted problems, disorganized central stock, outpatient surgery, spending much time dealing with family needs, late, inadequate, and useless help from nurse assistants, and ineffective morning rounds (P-value<0.05). Conclusion: Various performance obstacles are correlated with nurses' workload, affirms the significance of nursing work system characteristics. Interventions are recommended based on the results of this study in the work settings of nurses in ICUs. PMID:26933647

How Stereotype Threat Affects Healthy Older Adults’ Performance on Clinical Assessments of Cognitive Decline: The Key Role of Regulatory Fit

PubMed Central

Mather, Mara; Gatz, Margaret

2015-01-01

Objectives. Stereotype threat can impair older adults’ performance on clinical assessments for cognitive decline. We examined why this occurs. Based upon the regulatory focus account of stereotype threat, we predicted that the effects of stereotype threat should depend upon the assessments’ reward structure. Stereotype threat should be associated with poor performance when the assessment emphasizes gaining correct answers, but not when it emphasizes avoiding mistakes. Method. Healthy older adults completed a series of mental status examinations. Half of the participants completed these examinations under stereotype threat about their cognitive abilities. Monetary incentives were also manipulated. For half of the participants correct responding led to gains. For the remaining participants incorrect responding/forgetting led to losses. Results. Consistent with the regulatory focus account, stereotype threat was associated with poor performance when the mental status examinations had a gains-based structure, but not when they had a losses-based structure. Discussion. Older adults respond to stereotype threat by becoming vigilant to avoid the losses that will make them their worst. Researchers and clinicians can capitalize on this motivational change to combat stereotype threat’s negative effects. By using a loss-avoidance frame, stereotype threat’s negative effects can be attenuated or even eliminated. PMID:25752896

Reduced ovulation rate, failure to be mated and fertilization failure/embryo loss are the underlying causes of poor reproductive performance in juvenile ewes.

PubMed

Edwards, Sara J; Smaill, Bronwyn; O'Connell, Anne R; Johnstone, Peter D; Stevens, David R; Quirke, Laurel D; Farquhar, Philip A; Juengel, Jennifer L

2016-04-01

A ewe that is mated as a juvenile (producing a lamb at 1 year of age) will produce an average of only 0.6 lambs to weaning, compared to an average of 1.2 lambs in adult ewes. Understanding the underlying causes of this low reproductive efficiency and designing methods to improve or mitigate these effects could potentially increase adoption of mating juvenile ewes. In Experiment 1, 2 Cohorts of ewes, born a year apart, were mated in order to lamb at 1 and 2 years of age and the performance of the ewes at each age was compared. Onset of puberty, mating by the fertile ram, ovulation rate, early pregnancy (day 30-35) litter size, number of lambs born and number of lambs weaned were measured. In juvenile ewes, by day 35 of pregnancy, 43% of ova had failed to become a viable embryo and this early loss was the largest contributor to the poor reproductive performance observed. Compared with young adult ewes, ovulation rate was lower (p<0.001), fewer ova were exposed to sperm (p<0.001) and fertilization failure/embryo loss was increased (p<0.001) in juveniles. In Experiment 2, the early pregnancy litter size of juveniles was shown to be greater (p<0.001) in those ewes with a greater ovulation rate (p<0.001). Attaining puberty prior to introduction of the fertile ram was associated with an increased pregnancy rate (p<0.001). In juvenile ewes, failure to mate with the ram, lower ovulation rate and increased fertilisation failure/embryo loss underlie their poor reproductive performance. Copyright © 2016 Elsevier B.V. All rights reserved.

Social inequality in dynamic balance performance in an early old age Spanish population: the role of health and lifestyle associated factors.

PubMed

Rodríguez López, Santiago; Nilsson, Charlotte; Lund, Rikke; Montero, Pilar; Fernández-Ballesteros, Rocío; Avlund, Kirsten

2012-01-01

This study investigates the association between socioeconomic status (SES) and dynamic balance performance and whether lifestyle factors explained any possible associations. A total of 448 nondisabled individuals, age-range 54-75 years and enrolled in the Active Aging Longitudinal Study of Spain in 2006, constituted the study population. Baseline data of this cross-sectional study were obtained by personal interviews and objective measures of balance performance. The present study shows an educational gradient in poor dynamic balance, where individuals with no formal education had higher risk of poor balance, also after adjustment for age, gender, obesity and physical activity. In addition, obesity and sedentary physical activity were related to poor dynamic balance. The findings suggest an independent effect of both SES and behavioral factors on poor balance performance in the older Spanish population. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Phasic dopamine release in the rat nucleus accumbens predicts approach and avoidance performance

PubMed Central

Gentry, Ronny N.; Lee, Brian; Roesch, Matthew R.

2016-01-01

Dopamine (DA) is critical for reward processing, but significantly less is known about its role in punishment avoidance. Using a combined approach-avoidance task, we measured phasic DA release in the nucleus accumbens (NAc) of rats during presentation of cues that predicted reward, punishment or neutral outcomes and investigated individual differences based on avoidance performance. Here we show that DA release within a single microenvironment is higher for reward and avoidance cues compared with neutral cues and positively correlated with poor avoidance behaviour. We found that DA release delineates trial-type during sessions with good avoidance but is non-selective during poor avoidance, with high release correlating with poor performance. These data demonstrate that phasic DA is released during cued approach and avoidance within the same microenvironment and abnormal processing of value signals is correlated with poor performance. PMID:27786172

Deterioration in Teachers' Performance: Causes and Some Remedies

ERIC Educational Resources Information Center

Yariv, Eliezer

2011-01-01

Why do teachers become poor performers? In semi-structured interviews, forty elementary school principals in Israel described the personal story of one poor-performing staff member. Half of the problematic teachers were veteran teachers who faced a marked internal and external shift in mid-career. The seeds of their problems were probably planted…

Analysis of automatic repeat request methods for deep-space downlinks

NASA Technical Reports Server (NTRS)

Pollara, F.; Ekroot, L.

1995-01-01

Automatic repeat request (ARQ) methods cannot increase the capacity of a memoryless channel. However, they can be used to decrease the complexity of the channel-coding system to achieve essentially error-free transmission and to reduce link margins when the channel characteristics are poorly predictable. This article considers ARQ methods on a power-limited channel (e.g., the deep-space channel), where it is important to minimize the total power needed to transmit the data, as opposed to a bandwidth-limited channel (e.g., terrestrial data links), where the spectral efficiency or the total required transmission time is the most relevant performance measure. In the analysis, we compare the performance of three reference concatenated coded systems used in actual deep-space missions to that obtainable by ARQ methods using the same codes, in terms of required power, time to transmit with a given number of retransmissions, and achievable probability of word error. The ultimate limits of ARQ with an arbitrary number of retransmissions are also derived.

Exercising upper respiratory videoendoscopic evaluation of 100 nonracing performance horses with abnormal respiratory noise and/or poor performance.

PubMed

Davidson, E J; Martin, B B; Boston, R C; Parente, E J

2011-01-01

Although well documented in racehorses, there is paucity in the literature regarding the prevalence of dynamic upper airway abnormalities in nonracing performance horses. To describe upper airway function of nonracing performance horses with abnormal respiratory noise and/or poor performance via exercising upper airway videoendoscopy. Medical records of nonracing performance horses admitted for exercising evaluation with a chief complaint of abnormal respiratory noise and/or poor performance were reviewed. All horses had video recordings of resting and exercising upper airway endoscopy. Relationships between horse demographics, resting endoscopic findings, treadmill intensity and implementation of head and neck flexion during exercise with exercising endoscopic findings were examined. Dynamic upper airway obstructions were observed in 72% of examinations. Head and neck flexion was necessary to obtain a diagnosis in 21 horses. Pharyngeal wall collapse was the most prevalent upper airway abnormality, observed in 31% of the examinations. Complex abnormalities were noted in 27% of the examinations. Resting laryngeal dysfunction was significantly associated with dynamic arytenoid collapse and the odds of detecting intermittent dorsal displacement of the soft palate (DDSP) during exercise in horses with resting DDSP was only 7.7%. Exercising endoscopic observations were different from the resting observations in 54% of examinations. Dynamic upper airway obstructions were common in nonracing performance horses with respiratory noise and/or poor performance. Resting endoscopy was only helpful in determining exercising abnormalities with recurrent laryngeal neuropathy. This study emphasises the importance of exercising endoscopic evaluation in nonracing performance horses with abnormal respiratory noise and/or poor performance for accurate assessment of dynamic upper airway function. © 2010 EVJ Ltd.

Enhanced electrochemical performance and storage property of LiNi0.815Co0.15Al0.035O2 via Al gradient doping

NASA Astrophysics Data System (ADS)

Duan, Jianguo; Hu, Guorong; Cao, Yanbing; Tan, Chaopu; Wu, Ceng; Du, Ke; Peng, Zhongdong

2016-09-01

LiNi1-x-yCoxAlyO2 is a commonly used Ni-rich cathode material because of its relatively low cost, excellent rate capability and high gravimetric energy density. Surface modification is an efficient way to overcome the shortcomings of Ni-rich cathodes such as poor cycling stability and poor thermal stability. A high-powered concentration-gradient cathode material with an average composition of LiNi0.815Co0.15Al0.035O2 (LGNCAO) has been successfully synthesized by using spherical concentration-gradient Ni0.815Co0.15Al0.035(OH)2 (GNCA)as the starting material. An efficient design of the Al3+ precipitation method is developed, which enables obtaining spherical GNCA with ∼10 μm particle size and high tap density. In LGNCAO, the nickel and cobalt concentration decreases gradually whereas the aluminum concentration increases from the centre to the outer layer of each particle. Electrochemical performance and storage properties of LGNCAO have been investigated comparatively. The LGNCAO displays better electrochemical performance and improved storage stability than LNCAO.

Sleep Quality Prediction From Wearable Data Using Deep Learning.

PubMed

Sathyanarayana, Aarti; Joty, Shafiq; Fernandez-Luque, Luis; Ofli, Ferda; Srivastava, Jaideep; Elmagarmid, Ahmed; Arora, Teresa; Taheri, Shahrad

2016-11-04

The importance of sleep is paramount to health. Insufficient sleep can reduce physical, emotional, and mental well-being and can lead to a multitude of health complications among people with chronic conditions. Physical activity and sleep are highly interrelated health behaviors. Our physical activity during the day (ie, awake time) influences our quality of sleep, and vice versa. The current popularity of wearables for tracking physical activity and sleep, including actigraphy devices, can foster the development of new advanced data analytics. This can help to develop new electronic health (eHealth) applications and provide more insights into sleep science. The objective of this study was to evaluate the feasibility of predicting sleep quality (ie, poor or adequate sleep efficiency) given the physical activity wearable data during awake time. In this study, we focused on predicting good or poor sleep efficiency as an indicator of sleep quality. Actigraphy sensors are wearable medical devices used to study sleep and physical activity patterns. The dataset used in our experiments contained the complete actigraphy data from a subset of 92 adolescents over 1 full week. Physical activity data during awake time was used to create predictive models for sleep quality, in particular, poor or good sleep efficiency. The physical activity data from sleep time was used for the evaluation. We compared the predictive performance of traditional logistic regression with more advanced deep learning methods: multilayer perceptron (MLP), convolutional neural network (CNN), simple Elman-type recurrent neural network (RNN), long short-term memory (LSTM-RNN), and a time-batched version of LSTM-RNN (TB-LSTM). Deep learning models were able to predict the quality of sleep (ie, poor or good sleep efficiency) based on wearable data from awake periods. More specifically, the deep learning methods performed better than traditional logistic regression. “CNN had the highest specificity and sensitivity, and an overall area under the receiver operating characteristic (ROC) curve (AUC) of 0.9449, which was 46% better as compared with traditional logistic regression (0.6463). Deep learning methods can predict the quality of sleep based on actigraphy data from awake periods. These predictive models can be an important tool for sleep research and to improve eHealth solutions for sleep. ©Aarti Sathyanarayana, Shafiq Joty, Luis Fernandez-Luque, Ferda Ofli, Jaideep Srivastava, Ahmed Elmagarmid, Teresa Arora, Shahrad Taheri. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 04.11.2016.

Optimized iterative decoding method for TPC coded CPM

NASA Astrophysics Data System (ADS)

Ma, Yanmin; Lai, Penghui; Wang, Shilian; Xie, Shunqin; Zhang, Wei

2018-05-01

Turbo Product Code (TPC) coded Continuous Phase Modulation (CPM) system (TPC-CPM) has been widely used in aeronautical telemetry and satellite communication. This paper mainly investigates the improvement and optimization on the TPC-CPM system. We first add the interleaver and deinterleaver to the TPC-CPM system, and then establish an iterative system to iteratively decode. However, the improved system has a poor convergence ability. To overcome this issue, we use the Extrinsic Information Transfer (EXIT) analysis to find the optimal factors for the system. The experiments show our method is efficient to improve the convergence performance.

Methods to characterize charging effects

NASA Astrophysics Data System (ADS)

Slots, H.

1984-08-01

Methods to characterize charging in insulating material under high voltage dc stress, leading to electrical breakdown, are reviewed. The behavior of the charges can be studied by ac loss angle measurements after application or removal of dc bias. Measurements were performed on oil-paper and oil-Mylar systems. The poor reproducibility of the measurements makes it impossible to draw more than qualitative conclusions about the charging effects. With an ultrasound pressure wave the electric field distribution in a material can be determined. An alternative derivation for the transient response of a system which elucidates the influence of several parameters in a simple way is given.

Using Qualitative Methods with Poor Children in Urban Ethiopia: Opportunities & Challenges

ERIC Educational Resources Information Center

Tekola, Bethlehem; Griffin, Christine; Camfield, Laura

2009-01-01

This paper discusses the advantages and challenges of using qualitative methods to elicit poor children's perspectives about threats and positive influences on their wellbeing. It draws on research carried out by the author on the subjective experiences of poor children in Addis Ababa, the capital of Ethiopia in terms of their understandings of…

PPO and HMO performance factors: insurance company evaluation criteria.

PubMed

Rodin, B E

1993-01-01

A venture into managed care should be done only following the proper amount of due diligence. The goal should be to select the most effective managed care organization with the flexibility to meet long-term needs and the mission to work on an ongoing basis to improve service and managed care performance. Unfortunately, all too often purchasers do not demand critical information from managed care service providers. As a result, poor quality organizations have prospered and delivered less than satisfactory results. In fact, it is not unusual that savings from discounts are more than offset by increased use of health care services because of poor utilization management. It is important to be aware that use of the appropriate selection methods and monitoring performance on an ongoing basis are best done by dedicated professionals. They are also resource intensive and require a sophisticated systems capability. Since resources and systems involve significant investment, the most appropriate course for purchasers is to play the role of educated consumers. Detailed documentation should be demanded from all potential service providers to ensure that due diligence and ongoing management are in fact performed. The health care management staff at ITT Hartford is often told by managed care vendors that few other purchasers perform thorough review. It is imperative that managed care be scrutinized at least as closely as any important business venture.

Rice distribution planning for “the poor people” in Bandung, West Java, Indonesia.

NASA Astrophysics Data System (ADS)

Sutarman; Hidayat, Endang

2017-12-01

Bandung is one of the big and developed cities in Indonesia. The high economic growth in this city has an impact on increasing the prosperity of its citizens. However, the prosperity has not spread evenly. In fact, many residents of the city are still lack of rice. The party in charge of distributing rice to the poor is a state company called Bulog. Bulog has several warehouses with limited capacity to supply the poor. Three of them are Cisaranten Kidul, Main Warehouse and Citeureup warehouse. Bulog supplies rice to poor villages spread over 30 districts in Bandung. The allocation of rice for all districts needs to be improved so that the needs of the poor can be fulfilled with minimum allocation cost. Distribution planning conducted in this research was used Linear Programming method. Through this method, the optimization of rice allocation for the poor in Bandung can be obtained. Based on the finding, Linear programming method can be recommended as rice distribution pattern for poor people in Bandung with minimal logistics cost.

Toward Biopredictive Dissolution for Enteric Coated Dosage Forms.

PubMed

Al-Gousous, J; Amidon, G L; Langguth, P

2016-06-06

The aim of this work was to develop a phosphate buffer based dissolution method for enteric-coated formulations with improved biopredictivity for fasted conditions. Two commercially available enteric-coated aspirin products were used as model formulations (Aspirin Protect 300 mg, and Walgreens Aspirin 325 mg). The disintegration performance of these products in a physiological 8 mM pH 6.5 bicarbonate buffer (representing the conditions in the proximal small intestine) was used as a standard to optimize the employed phosphate buffer molarity. To account for the fact that a pH and buffer molarity gradient exists along the small intestine, the introduction of such a gradient was proposed for products with prolonged lag times (when it leads to a release lower than 75% in the first hour post acid stage) in the proposed buffer. This would allow the method also to predict the performance of later-disintegrating products. Dissolution performance using the accordingly developed method was compared to that observed when using two well-established dissolution methods: the United States Pharmacopeia (USP) method and blank fasted state simulated intestinal fluid (FaSSIF). The resulting dissolution profiles were convoluted using GastroPlus software to obtain predicted pharmacokinetic profiles. A pharmacokinetic study on healthy human volunteers was performed to evaluate the predictions made by the different dissolution setups. The novel method provided the best prediction, by a relatively wide margin, for the difference between the lag times of the two tested formulations, indicating its being able to predict the post gastric emptying onset of drug release with reasonable accuracy. Both the new and the blank FaSSIF methods showed potential for establishing in vitro-in vivo correlation (IVIVC) concerning the prediction of Cmax and AUC0-24 (prediction errors not more than 20%). However, these predictions are strongly affected by the highly variable first pass metabolism necessitating the evaluation of an absorption rate metric that is more independent of the first-pass effect. The Cmax/AUC0-24 ratio was selected for this purpose. Regarding this metric's predictions, the new method provided very good prediction of the two products' performances relative to each other (only 1.05% prediction error in this regard), while its predictions for the individual products' values in absolute terms were borderline, narrowly missing the regulatory 20% prediction error limits (21.51% for Aspirin Protect and 22.58% for Walgreens Aspirin). The blank FaSSIF-based method provided good Cmax/AUC0-24 ratio prediction, in absolute terms, for Aspirin Protect (9.05% prediction error), but its prediction for Walgreens Aspirin (33.97% prediction error) was overwhelmingly poor. Thus it gave practically the same average but much higher maximum prediction errors compared to the new method, and it was strongly overdiscriminating as for predicting their performances relative to one another. The USP method, despite not being overdiscriminating, provided poor predictions of the individual products' Cmax/AUC0-24 ratios. This indicates that, overall, the new method is of improved biopredictivity compared to established methods.

Training children aged 5-10 years in manual compliance control to improve drawing and handwriting.

PubMed

Bingham, Geoffrey P; Snapp-Childs, Winona

2018-04-12

A large proportion of school-aged children exhibit poor drawing and handwriting. This prevalence limits the availability of therapy. We developed an automated method for training improved manual compliance control and relatedly, prospective control of a stylus. The approach included a difficult training task, while providing parametrically modifiable support that enables the children to perform successfully while developing good compliance control. The task was to use a stylus to push a bead along a 3D wire path. Support was provided by making the wire magnetically attractive to the stylus. Support was progressively reduced as 3D tracing performance improved. We report studies that (1) compared performance of Typically Developing (TD) children and children with Developmental Coordination Disorder (DCD), (2) tested training with active versus passive movement, (3) tested progressively reduced versus constant or no support during training, (4) tested children of different ages, (5) tested the transfer of training to a drawing task, (6) tested the specificity of training in respect to the size, shape and dimensionality of figures, and (7) investigated the relevance of the training task to the Beery VMI, an inventory used to diagnose DCD. The findings were as follows. (1) Pre-training performance of TD and DCD children was the same and good with high support but distinct and poor with low support. Support yielded good self-efficacy that motivated training. Post training performance with no support was improved and the same for TD and DCD children. (2) Actively controlled movements were required for improved performance. (3) Progressively reduced support was required for good performance during and after training. (4) Age differences in performance during pre-training were eliminated post-training. (5) Improvements transferred to drawing. (6) There was no evidence of specificity of training in transfer. (7) Disparate Beery scores were reflected in pre-training but not post-training performance. We conclude that the method improves manual compliance control, and more generally, prospective control of movements used in drawing performance. Copyright © 2018. Published by Elsevier B.V.

Empowering the rural poor through EO products and services—An impact assessment

NASA Astrophysics Data System (ADS)

Diwakar, P. G.; Ranganath, B. K.; Gowrisankar, D.; Jayaraman, V.

2008-07-01

With the advent of technology in the form of space-based imaging, network-based computation and information technology, the focus has shifted to how these technologies could change the livelihoods of rural community and put them on the path of developmental processes. Many rural villages in India do not have right kind of infrastructure and connectivity, which makes it difficult for any developmental program to perform successfully. This makes them more vulnerable and further cut off from the mainstream developmental programs in the country. There are large tracts of arid and semi-arid lands in many parts of the country, which requires scientific inputs and improved farming practices for sustenance of poor communities under tough conditions. Unless some simple and cost-effective methods are evolved and taken to the field level, it is difficult to see positive developments in such areas and stop people from migrating to different areas for livelihood options. Integrated watershed development program with innovative practices and holistic approach could bring about positive changes in such poverty stricken areas that host vulnerable groups who experience the hardship due to poor local natural resources conditions and living standards. An optimal combination of space technology and information technology has been successfully used, through participatory methods, to empower the rural poor in realizing better livelihood possibilities. An attempt is made in this paper to find solutions for such problematic areas with some innovative tools and techniques that involve user-friendly delivery of EO products and services for the benefit of the rural community and help them in decision making at local level.

A simplified focusing and astigmatism correction method for a scanning electron microscope

NASA Astrophysics Data System (ADS)

Lu, Yihua; Zhang, Xianmin; Li, Hai

2018-01-01

Defocus and astigmatism can lead to blurred images and poor resolution. This paper presents a simplified method for focusing and astigmatism correction of a scanning electron microscope (SEM). The method consists of two steps. In the first step, the fast Fourier transform (FFT) of the SEM image is performed and the FFT is subsequently processed with a threshold to achieve a suitable result. In the second step, the threshold FFT is used for ellipse fitting to determine the presence of defocus and astigmatism. The proposed method clearly provides the relationships between the defocus, the astigmatism and the direction of stretching of the FFT, and it can determine the astigmatism in a single image. Experimental studies are conducted to demonstrate the validity of the proposed method.

Automated Transition State Theory Calculations for High-Throughput Kinetics.

PubMed

Bhoorasingh, Pierre L; Slakman, Belinda L; Seyedzadeh Khanshan, Fariba; Cain, Jason Y; West, Richard H

2017-09-21

A scarcity of known chemical kinetic parameters leads to the use of many reaction rate estimates, which are not always sufficiently accurate, in the construction of detailed kinetic models. To reduce the reliance on these estimates and improve the accuracy of predictive kinetic models, we have developed a high-throughput, fully automated, reaction rate calculation method, AutoTST. The algorithm integrates automated saddle-point geometry search methods and a canonical transition state theory kinetics calculator. The automatically calculated reaction rates compare favorably to existing estimated rates. Comparison against high level theoretical calculations show the new automated method performs better than rate estimates when the estimate is made by a poor analogy. The method will improve by accounting for internal rotor contributions and by improving methods to determine molecular symmetry.

Recommendations for level-determined sampling in wells

NASA Astrophysics Data System (ADS)

Lerner, David N.; Teutsch, Georg

1995-10-01

Level-determined samples of groundwater are increasingly important for hydrogeological studies. The techniques for collecting them range from the use of purpose drilled wells, sometimes with sophisticated dedicated multi-level samplers in them, to a variety of methods used in open wells. Open, often existing, wells are frequently used on cost grounds, but there are risks of obtaining poor and unrepresentative samples. Alternative approaches to level-determined sampling incorporate seven concepts: depth sampling; packer systems; individual wells; dedicated multi-level systems; separation pumping; baffle systems; multi-port sock samplers. These are outlined and evaluated in terms of the environment to be sampled, and the features and performance of the methods. Recommendations are offered to match methods to sampling problems.

Embedded measures of performance validity using verbal fluency tests in a clinical sample.

PubMed

Sugarman, Michael A; Axelrod, Bradley N

2015-01-01

The objective of this study was to determine to what extent verbal fluency measures can be used as performance validity indicators during neuropsychological evaluation. Participants were clinically referred for neuropsychological evaluation in an urban-based Veteran's Affairs hospital. Participants were placed into 2 groups based on their objectively evaluated effort on performance validity tests (PVTs). Individuals who exhibited credible performance (n = 431) failed 0 PVTs, and those with poor effort (n = 192) failed 2 or more PVTs. All participants completed the Controlled Oral Word Association Test (COWAT) and Animals verbal fluency measures. We evaluated how well verbal fluency scores could discriminate between the 2 groups. Raw scores and T scores for Animals discriminated between the credible performance and poor-effort groups with 90% specificity and greater than 40% sensitivity. COWAT scores had lower sensitivity for detecting poor effort. A combination of FAS and Animals scores into logistic regression models yielded acceptable group classification, with 90% specificity and greater than 44% sensitivity. Verbal fluency measures can yield adequate detection of poor effort during neuropsychological evaluation. We provide suggested cut points and logistic regression models for predicting the probability of poor effort in our clinical setting and offer suggested cutoff scores to optimize sensitivity and specificity.

A Cascaded Approach for Correcting Ionospheric Contamination with Large Amplitude in HF Skywave Radars

PubMed Central

Wei, Yinsheng; Guo, Rujiang; Xu, Rongqing; Tang, Xiudong

2014-01-01

Ionospheric phase perturbation with large amplitude causes broadening sea clutter's Bragg peaks to overlap each other; the performance of traditional decontamination methods about filtering Bragg peak is poor, which greatly limits the detection performance of HF skywave radars. In view of the ionospheric phase perturbation with large amplitude, this paper proposes a cascaded approach based on improved S-method to correct the ionospheric phase contamination. This approach consists of two correction steps. At the first step, a time-frequency distribution method based on improved S-method is adopted and an optimal detection method is designed to obtain a coarse ionospheric modulation estimation from the time-frequency distribution. At the second correction step, based on the phase gradient algorithm (PGA) is exploited to eliminate the residual contamination. Finally, use the measured data to verify the effectiveness of the method. Simulation results show the time-frequency resolution of this method is high and is not affected by the interference of the cross term; ionospheric phase perturbation with large amplitude can be corrected in low signal-to-noise (SNR); such a cascade correction method has a good effect. PMID:24578656

Getting off on the Wrong Foot: Longitudinal Effects of Hispanic Students' Stability Attributions Following Poor Initial Test Performance

ERIC Educational Resources Information Center

Cox, Cody B.; Yang, Yan

2012-01-01

Though studies have established that following poor performance, attributions to stable causes affect the performance of minority students, few studies have explored the impact of stability attributions over time. This study explored attributions following initial failure among a predominantly Hispanic student population. We measured students'…

Performance of Seven Seed Sources of Blue Spruce in Central North Dakota

Treesearch

David H. Dawson; Paul O. Rudolf

1966-01-01

Blue spruce (Picea pungens Engelm.) has been planted quite extensively in North Dakota shelterbelts and farmstead windbreaks. Generally survival and growth have been promising, but there is considerable variation in performance of individual trees or plantations. Poorly adapted seed sources have been suspected as one cause for poor performance. There should be...

Computational aspects of sensitivity calculations in linear transient structural analysis. Ph.D. Thesis - Virginia Polytechnic Inst. and State Univ.

NASA Technical Reports Server (NTRS)

Greene, William H.

1990-01-01

A study was performed focusing on the calculation of sensitivities of displacements, velocities, accelerations, and stresses in linear, structural, transient response problems. One significant goal of the study was to develop and evaluate sensitivity calculation techniques suitable for large-order finite element analyses. Accordingly, approximation vectors such as vibration mode shapes are used to reduce the dimensionality of the finite element model. Much of the research focused on the accuracy of both response quantities and sensitivities as a function of number of vectors used. Two types of sensitivity calculation techniques were developed and evaluated. The first type of technique is an overall finite difference method where the analysis is repeated for perturbed designs. The second type of technique is termed semi-analytical because it involves direct, analytical differentiation of the equations of motion with finite difference approximation of the coefficient matrices. To be computationally practical in large-order problems, the overall finite difference methods must use the approximation vectors from the original design in the analyses of the perturbed models. In several cases this fixed mode approach resulted in very poor approximations of the stress sensitivities. Almost all of the original modes were required for an accurate sensitivity and for small numbers of modes, the accuracy was extremely poor. To overcome this poor accuracy, two semi-analytical techniques were developed. The first technique accounts for the change in eigenvectors through approximate eigenvector derivatives. The second technique applies the mode acceleration method of transient analysis to the sensitivity calculations. Both result in accurate values of the stress sensitivities with a small number of modes and much lower computational costs than if the vibration modes were recalculated and then used in an overall finite difference method.

Annealed Importance Sampling Reversible Jump MCMC algorithms

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

Karagiannis, Georgios; Andrieu, Christophe

2013-03-20

It will soon be 20 years since reversible jump Markov chain Monte Carlo (RJ-MCMC) algorithms have been proposed. They have significantly extended the scope of Markov chain Monte Carlo simulation methods, offering the promise to be able to routinely tackle transdimensional sampling problems, as encountered in Bayesian model selection problems for example, in a principled and flexible fashion. Their practical efficient implementation, however, still remains a challenge. A particular difficulty encountered in practice is in the choice of the dimension matching variables (both their nature and their distribution) and the reversible transformations which allow one to define the one-to-one mappingsmore » underpinning the design of these algorithms. Indeed, even seemingly sensible choices can lead to algorithms with very poor performance. The focus of this paper is the development and performance evaluation of a method, annealed importance sampling RJ-MCMC (aisRJ), which addresses this problem by mitigating the sensitivity of RJ-MCMC algorithms to the aforementioned poor design. As we shall see the algorithm can be understood as being an “exact approximation” of an idealized MCMC algorithm that would sample from the model probabilities directly in a model selection set-up. Such an idealized algorithm may have good theoretical convergence properties, but typically cannot be implemented, and our algorithms can approximate the performance of such idealized algorithms to an arbitrary degree while not introducing any bias for any degree of approximation. Our approach combines the dimension matching ideas of RJ-MCMC with annealed importance sampling and its Markov chain Monte Carlo implementation. We illustrate the performance of the algorithm with numerical simulations which indicate that, although the approach may at first appear computationally involved, it is in fact competitive.« less

Protocol for the process evaluation of interventions combining performance-based financing with health equity in Burkina Faso.

PubMed

Ridde, Valéry; Turcotte-Tremblay, Anne-Marie; Souares, Aurélia; Lohmann, Julia; Zombré, David; Koulidiati, Jean Louis; Yaogo, Maurice; Hien, Hervé; Hunt, Matthew; Zongo, Sylvie; De Allegri, Manuela

2014-10-12

The low quality of healthcare and the presence of user fees in Burkina Faso contribute to low utilization of healthcare and elevated levels of mortality. To improve access to high-quality healthcare and equity, national authorities are testing different intervention arms that combine performance-based financing with community-based health insurance and pro-poor targeting. There is a need to evaluate the implementation of these unique approaches. We developed a research protocol to analyze the conditions that led to the emergence of these intervention arms, the fidelity between the activities initially planned and those conducted, the implementation and adaptation processes, the sustainability of the interventions, the possibilities for scaling them up, and their ethical implications. The study adopts a longitudinal multiple case study design with several embedded levels of analyses. To represent the diversity of contexts where the intervention arms are carried out, we will select three districts. Within districts, we will select both primary healthcare centers (n =18) representing different intervention arms and the district or regional hospital (n =3). We will select contrasted cases in relation to their initial performance (good, fair, poor). Over a period of 18 months, we will use quantitative and qualitative data collection and analytical tools to study these cases including in-depth interviews, participatory observation, research diaries, and questionnaires. We will give more weight to qualitative methods compared to quantitative methods. Performance-based financing is expanding rapidly across low- and middle-income countries. The results of this study will enable researchers and decision makers to gain a better understanding of the factors that can influence the implementation and the sustainability of complex interventions aiming to increase healthcare quality as well as equity.

Temporal diagnostic analysis of the SWAT model to detect dominant periods of poor model performance

NASA Astrophysics Data System (ADS)

Guse, Björn; Reusser, Dominik E.; Fohrer, Nicola

2013-04-01

Hydrological models generally include thresholds and non-linearities, such as snow-rain-temperature thresholds, non-linear reservoirs, infiltration thresholds and the like. When relating observed variables to modelling results, formal methods often calculate performance metrics over long periods, reporting model performance with only few numbers. Such approaches are not well suited to compare dominating processes between reality and model and to better understand when thresholds and non-linearities are driving model results. We present a combination of two temporally resolved model diagnostic tools to answer when a model is performing (not so) well and what the dominant processes are during these periods. We look at the temporal dynamics of parameter sensitivities and model performance to answer this question. For this, the eco-hydrological SWAT model is applied in the Treene lowland catchment in Northern Germany. As a first step, temporal dynamics of parameter sensitivities are analyzed using the Fourier Amplitude Sensitivity test (FAST). The sensitivities of the eight model parameters investigated show strong temporal variations. High sensitivities were detected for two groundwater (GW_DELAY, ALPHA_BF) and one evaporation parameters (ESCO) most of the time. The periods of high parameter sensitivity can be related to different phases of the hydrograph with dominances of the groundwater parameters in the recession phases and of ESCO in baseflow and resaturation periods. Surface runoff parameters show high parameter sensitivities in phases of a precipitation event in combination with high soil water contents. The dominant parameters give indication for the controlling processes during a given period for the hydrological catchment. The second step included the temporal analysis of model performance. For each time step, model performance was characterized with a "finger print" consisting of a large set of performance measures. These finger prints were clustered into four reoccurring patterns of typical model performance, which can be related to different phases of the hydrograph. Overall, the baseflow cluster has the lowest performance. By combining the periods with poor model performance with the dominant model components during these phases, the groundwater module was detected as the model part with the highest potential for model improvements. The detection of dominant processes in periods of poor model performance enhances the understanding of the SWAT model. Based on this, concepts how to improve the SWAT model structure for the application in German lowland catchment are derived.

Measuring Health System Strengthening: Application of the Balanced Scorecard Approach to Rank the Baseline Performance of Three Rural Districts in Zambia

PubMed Central

Mutale, Wilbroad; Godfrey-Fausset, Peter; Mwanamwenge, Margaret Tembo; Kasese, Nkatya; Chintu, Namwinga; Balabanova, Dina; Spicer, Neil; Ayles, Helen

2013-01-01

Introduction There is growing interest in health system performance and recently WHO launched a report on health systems strengthening emphasising the need for close monitoring using system-wide approaches. One recent method is the balanced scorecard system. There is limited application of this method in middle- and low-income countries. This paper applies the concept of balanced scorecard to describe the baseline status of three intervention districts in Zambia. Methodology The Better Health Outcome through Mentoring and Assessment (BHOMA) project is a randomised step-wedged community intervention that aims to strengthen the health system in three districts in the Republic of Zambia. To assess the baseline status of the participating districts we used a modified balanced scorecard approach following the domains highlighted in the MOH 2011 Strategic Plan. Results Differences in performance were noted by district and residence. Finance and service delivery domains performed poorly in all study districts. The proportion of the health workers receiving training in the past 12 months was lowest in Kafue (58%) and highest in Luangwa district (77%). Under service capacity, basic equipment and laboratory capacity scores showed major variation, with Kafue and Luangwa having lower scores when compared to Chongwe. The finance domain showed that Kafue and Chongwe had lower scores (44% and 47% respectively). Regression model showed that children's clinical observation scores were negatively correlated with drug availability (coeff −0.40, p = 0.02). Adult clinical observation scores were positively association with adult service satisfaction score (coeff 0.82, p = 0.04) and service readiness (coeff 0.54, p = 0.03). Conclusion The study applied the balanced scorecard to describe the baseline status of 42 health facilities in three districts of Zambia. Differences in performance were noted by district and residence in most domains with finance and service delivery performing poorly in all study districts. This tool could be valuable in monitoring and evaluation of health systems. PMID:23555590

Measuring health system strengthening: application of the balanced scorecard approach to rank the baseline performance of three rural districts in Zambia.

PubMed

Mutale, Wilbroad; Godfrey-Fausset, Peter; Mwanamwenge, Margaret Tembo; Kasese, Nkatya; Chintu, Namwinga; Balabanova, Dina; Spicer, Neil; Ayles, Helen

2013-01-01

There is growing interest in health system performance and recently WHO launched a report on health systems strengthening emphasising the need for close monitoring using system-wide approaches. One recent method is the balanced scorecard system. There is limited application of this method in middle- and low-income countries. This paper applies the concept of balanced scorecard to describe the baseline status of three intervention districts in Zambia. The Better Health Outcome through Mentoring and Assessment (BHOMA) project is a randomised step-wedged community intervention that aims to strengthen the health system in three districts in the Republic of Zambia. To assess the baseline status of the participating districts we used a modified balanced scorecard approach following the domains highlighted in the MOH 2011 Strategic Plan. Differences in performance were noted by district and residence. Finance and service delivery domains performed poorly in all study districts. The proportion of the health workers receiving training in the past 12 months was lowest in Kafue (58%) and highest in Luangwa district (77%). Under service capacity, basic equipment and laboratory capacity scores showed major variation, with Kafue and Luangwa having lower scores when compared to Chongwe. The finance domain showed that Kafue and Chongwe had lower scores (44% and 47% respectively). Regression model showed that children's clinical observation scores were negatively correlated with drug availability (coeff -0.40, p = 0.02). Adult clinical observation scores were positively association with adult service satisfaction score (coeff 0.82, p = 0.04) and service readiness (coeff 0.54, p = 0.03). The study applied the balanced scorecard to describe the baseline status of 42 health facilities in three districts of Zambia. Differences in performance were noted by district and residence in most domains with finance and service delivery performing poorly in all study districts. This tool could be valuable in monitoring and evaluation of health systems.

Paediatric cerebrovascular CT angiography—towards better image quality

PubMed Central

Thust, Stefanie C.; Chong, Wui Khean Kling; Gunny, Roxana; Mazumder, Asif; Poitelea, Marius; Welsh, Anna; Ederies, Ash

2014-01-01

Background Paediatric cerebrovascular CT angiography (CTA) can be challenging to perform due to variable cardiovascular physiology between different age groups and the risk of movement artefact. This analysis aimed to determine what proportion of CTA at our institution was of diagnostic quality and identify technical factors which could be improved. Materials and methods a retrospective analysis of 20 cases was performed at a national paediatric neurovascular centre assessing image quality with a subjective scoring system and Hounsfield Unit (HU) measurements. Demographic data, contrast dose, flow rate and triggering times were recorded for each patient. Results Using a qualitative scoring system, 75% of studies were found to be of diagnostic quality (n=9 ‘good’, n=6 ‘satisfactory’) and 25% (n=5) were ‘poor’. Those judged subjectively to be poor had arterial contrast density measured at less than 250 HU. Increased arterial opacification was achieved for cases performed with an increased flow rate (2.5-4 mL/s) and higher intravenous contrast dose (2 mL/kg). Triggering was found to be well timed in nine cases, early in four cases and late in seven cases. Of the scans triggered early, 75% were poor. Of the scans triggered late, less (29%) were poor. Conclusions High flow rates (>2.5 mL/s) were a key factor for achieving high quality paediatric cerebrovascular CTA imaging. However, appropriate triggering by starting the scan immediately on contrast opacification of the monitoring vessel plays an important role and could maintain image quality when flow rates were lower. Early triggering appeared more detrimental than late. PMID:25525579

Multisource Feedback in the Ambulatory Setting

PubMed Central

Warm, Eric J.; Schauer, Daniel; Revis, Brian; Boex, James R.

2010-01-01

Background The Accreditation Council for Graduate Medical Education has mandated multisource feedback (MSF) in the ambulatory setting for internal medicine residents. Few published reports demonstrate actual MSF results for a residency class, and fewer still include clinical quality measures and knowledge-based testing performance in the data set. Methods Residents participating in a year-long group practice experience called the “long-block” received MSF that included self, peer, staff, attending physician, and patient evaluations, as well as concomitant clinical quality data and knowledge-based testing scores. Residents were given a rank for each data point compared with peers in the class, and these data were reviewed with the chief resident and program director over the course of the long-block. Results Multisource feedback identified residents who performed well on most measures compared with their peers (10%), residents who performed poorly on most measures compared with their peers (10%), and residents who performed well on some measures and poorly on others (80%). Each high-, intermediate-, and low-performing resident had a least one aspect of the MSF that was significantly lower than the other, and this served as the basis of formative feedback during the long-block. Conclusion Use of multi-source feedback in the ambulatory setting can identify high-, intermediate-, and low-performing residents and suggest specific formative feedback for each. More research needs to be done on the effect of such feedback, as well as the relationships between each of the components in the MSF data set. PMID:21975632

Costing Hospital Surgery Services: The Method Matters

PubMed Central

Mercier, Gregoire; Naro, Gerald

2014-01-01

Background Accurate hospital costs are required for policy-makers, hospital managers and clinicians to improve efficiency and transparency. However, different methods are used to allocate direct costs, and their agreement is poorly understood. The aim of this study was to assess the agreement between bottom-up and top-down unit costs of a large sample of surgical operations in a French tertiary centre. Methods Two thousand one hundred and thirty consecutive procedures performed between January and October 2010 were analysed. Top-down costs were based on pre-determined weights, while bottom-up costs were calculated through an activity-based costing (ABC) model. The agreement was assessed using correlation coefficients and the Bland and Altman method. Variables associated with the difference between methods were identified with bivariate and multivariate linear regressions. Results The correlation coefficient amounted to 0.73 (95%CI: 0.72; 0.76). The overall agreement between methods was poor. In a multivariate analysis, the cost difference was independently associated with age (Beta = −2.4; p = 0.02), ASA score (Beta = 76.3; p<0.001), RCI (Beta = 5.5; p<0.001), staffing level (Beta = 437.0; p<0.001) and intervention duration (Beta = −10.5; p<0.001). Conclusions The ability of the current method to provide relevant information to managers, clinicians and payers is questionable. As in other European countries, a shift towards time-driven activity-based costing should be advocated. PMID:24817167

The numerical study and comparison of radial basis functions in applications of the dual reciprocity boundary element method to convection-diffusion problems

NASA Astrophysics Data System (ADS)

Chanthawara, Krittidej; Kaennakham, Sayan; Toutip, Wattana

2016-02-01

The methodology of Dual Reciprocity Boundary Element Method (DRBEM) is applied to the convection-diffusion problems and investigating its performance is our first objective of the work. Seven types of Radial Basis Functions (RBF); Linear, Thin-plate Spline, Cubic, Compactly Supported, Inverse Multiquadric, Quadratic, and that proposed by [12], were closely investigated in order to numerically compare their effectiveness drawbacks etc. and this is taken as our second objective. A sufficient number of simulations were performed covering as many aspects as possible. Varidated against both exacts and other numerical works, the final results imply strongly that the Thin-Plate Spline and Linear type of RBF are superior to others in terms of both solutions' quality and CPU-time spent while the Inverse Multiquadric seems to poorly yield the results. It is also found that DRBEM can perform relatively well at moderate level of convective force and as anticipated becomes unstable when the problem becomes more convective-dominated, as normally found in all classical mesh-dependence methods.

A Novel Segmentation Approach Combining Region- and Edge-Based Information for Ultrasound Images

PubMed Central

Luo, Yaozhong; Liu, Longzhong; Li, Xuelong

2017-01-01

Ultrasound imaging has become one of the most popular medical imaging modalities with numerous diagnostic applications. However, ultrasound (US) image segmentation, which is the essential process for further analysis, is a challenging task due to the poor image quality. In this paper, we propose a new segmentation scheme to combine both region- and edge-based information into the robust graph-based (RGB) segmentation method. The only interaction required is to select two diagonal points to determine a region of interest (ROI) on the original image. The ROI image is smoothed by a bilateral filter and then contrast-enhanced by histogram equalization. Then, the enhanced image is filtered by pyramid mean shift to improve homogeneity. With the optimization of particle swarm optimization (PSO) algorithm, the RGB segmentation method is performed to segment the filtered image. The segmentation results of our method have been compared with the corresponding results obtained by three existing approaches, and four metrics have been used to measure the segmentation performance. The experimental results show that the method achieves the best overall performance and gets the lowest ARE (10.77%), the second highest TPVF (85.34%), and the second lowest FPVF (4.48%). PMID:28536703

Factors Affecting the Delivery, Access, and Use of Interventions to Prevent Malaria in Pregnancy in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

PubMed Central

Hill, Jenny; Hoyt, Jenna; van Eijk, Anna Maria; D'Mello-Guyett, Lauren; ter Kuile, Feiko O.; Steketee, Rick; Smith, Helen; Webster, Jayne

2013-01-01

Background Malaria in pregnancy has important consequences for mother and baby. Coverage with the World Health Organization–recommended prevention strategy for pregnant women in sub-Saharan Africa of intermittent preventive treatment in pregnancy (IPTp) and insecticide-treated nets (ITNs) is low. We conducted a systematic review to explore factors affecting delivery, access, and use of IPTp and ITNs among healthcare providers and women. Methods and Results We searched the Malaria in Pregnancy Library and Global Health Database from 1 January 1990 to 23 April 2013, without language restriction. Data extraction was performed by two investigators independently, and data was appraised for quality and content. Data on barriers and facilitators, and the effect of interventions, were explored using content analysis and narrative synthesis. We conducted a meta-analysis of determinants of IPTp and ITN uptake using random effects models, and performed subgroup analysis to evaluate consistency across interventions and study populations, countries, and enrolment sites. We did not perform a meta-ethnography of qualitative data. Ninety-eight articles were included, of which 20 were intervention studies. Key barriers to the provision of IPTp and ITNs were unclear policy and guidance on IPTp; general healthcare system issues, such as stockouts and user fees; health facility issues stemming from poor organisation, leading to poor quality of care; poor healthcare provider performance, including confusion over the timing of each IPTp dose; and women's poor antenatal attendance, affecting IPTp uptake. Key determinants of IPTp coverage were education, knowledge about malaria/IPTp, socio-economic status, parity, and number and timing of antenatal clinic visits. Key determinants of ITN coverage were employment status, education, knowledge about malaria/ITNs, age, and marital status. Predictors showed regional variations. Conclusions Delivery of ITNs through antenatal clinics presents fewer problems than delivery of IPTp. Many obstacles to IPTp delivery are relatively simple barriers that could be resolved in the short term. Other barriers are more entrenched within the overall healthcare system or socio-economic/cultural contexts, and will require medium- to long-term strategies. Please see later in the article for the Editors' Summary PMID:23935459

Comparison of three commercially available fit-test methods.

PubMed

Janssen, Larry L; Luinenburg, D Michael; Mullins, Haskell E; Nelson, Thomas J

2002-01-01

American National Standards Institute (ANSI) standard Z88.10, Respirator Fit Testing Methods, includes criteria to evaluate new fit-tests. The standard allows generated aerosol, particle counting, or controlled negative pressure quantitative fit-tests to be used as the reference method to determine acceptability of a new test. This study examined (1) comparability of three Occupational Safety and Health Administration-accepted fit-test methods, all of which were validated using generated aerosol as the reference method; and (2) the effect of the reference method on the apparent performance of a fit-test method under evaluation. Sequential fit-tests were performed using the controlled negative pressure and particle counting quantitative fit-tests and the bitter aerosol qualitative fit-test. Of 75 fit-tests conducted with each method, the controlled negative pressure method identified 24 failures; bitter aerosol identified 22 failures; and the particle counting method identified 15 failures. The sensitivity of each method, that is, agreement with the reference method in identifying unacceptable fits, was calculated using each of the other two methods as the reference. None of the test methods met the ANSI sensitivity criterion of 0.95 or greater when compared with either of the other two methods. These results demonstrate that (1) the apparent performance of any fit-test depends on the reference method used, and (2) the fit-tests evaluated use different criteria to identify inadequately fitting respirators. Although "acceptable fit" cannot be defined in absolute terms at this time, the ability of existing fit-test methods to reject poor fits can be inferred from workplace protection factor studies.

Orthographic Processing and Visual Sequential Memory in Unexpectedly Poor Spellers

ERIC Educational Resources Information Center

Holmes, Virginia M.; Malone, Aisling M.; Redenbach, Holly

2008-01-01

Does unexpectedly poor spelling in adults result from inferior visual sequential memory? In one experiment, unexpectedly poor spellers performed significantly worse than better spellers in the immediate reproduction of sequences of visual symbols, but in a second experiment, the effect was not replicated. Poor spellers were also no worse at the…

Evaluation of multiple precipitation products across Mainland China using the triple collocation method without ground truth

NASA Astrophysics Data System (ADS)

Tang, G.; Li, C.; Hong, Y.; Long, D.

2017-12-01

Proliferation of satellite and reanalysis precipitation products underscores the need to evaluate their reliability, particularly over ungauged or poorly gauged regions. However, it is really challenging to perform such evaluations over regions lacking ground truth data. Here, using the triple collocation (TC) method that is capable of evaluating relative uncertainties in different products without ground truth, we evaluate five satellite-based precipitation products and comparatively assess uncertainties in three types of independent precipitation products, e.g., satellite-based, ground-observed, and model reanalysis over Mainland China, including a ground-based precipitation dataset (the gauge based daily precipitation analysis, CGDPA), the latest version of the European reanalysis agency reanalysis (ERA-interim) product, and five satellite-based products (i.e., 3B42V7, 3B42RT of TMPA, IMERG, CMORPH-CRT, PERSIANN-CDR) on a regular 0.25° grid at the daily timescale from 2013 to 2015. First, the effectiveness of the TC method is evaluated by comparison with traditional methods based on ground observations in a densely gauged region. Results show that the TC method is reliable because the correlation coefficient (CC) and root mean square error (RMSE) are close to those based on the traditional method with a maximum difference only up to 0.08 and 0.71 (mm/day) for CC and RMSE, respectively. Then, the TC method is applied to Mainland China and the Tibetan Plateau (TP). Results indicate that: (1) the overall performance of IMERG is better than the other satellite products over Mainland China; (2) over grid cells without rain gauges in the TP, IMERG and ERA show better performance than CGDPA, indicating the potential of remote sensing and reanalysis data over these regions and the inherent uncertainty of CGDPA due to interpolation using sparsely gauged data; (3) both TMPA-3B42 and CMORPH-CRT have some unexpected CC values over certain grid cells that contain water bodies, reaffirming the overestimation of precipitation over inland water bodies. Overall, the TC method provides not only reliable cross-validation results of precipitation estimates over Mainland China but also a new perspective as to compressively assess multi-source precipitation products, particularly over poorly gauged regions.

Visual navigation using edge curve matching for pinpoint planetary landing

NASA Astrophysics Data System (ADS)

Cui, Pingyuan; Gao, Xizhen; Zhu, Shengying; Shao, Wei

2018-05-01

Pinpoint landing is challenging for future Mars and asteroid exploration missions. Vision-based navigation scheme based on feature detection and matching is practical and can achieve the required precision. However, existing algorithms are computationally prohibitive and utilize poor-performance measurements, which pose great challenges for the application of visual navigation. This paper proposes an innovative visual navigation scheme using crater edge curves during descent and landing phase. In the algorithm, the edge curves of the craters tracked from two sequential images are utilized to determine the relative attitude and position of the lander through a normalized method. Then, considering error accumulation of relative navigation, a method is developed. That is to integrate the crater-based relative navigation method with crater-based absolute navigation method that identifies craters using a georeferenced database for continuous estimation of absolute states. In addition, expressions of the relative state estimate bias are derived. Novel necessary and sufficient observability criteria based on error analysis are provided to improve the navigation performance, which hold true for similar navigation systems. Simulation results demonstrate the effectiveness and high accuracy of the proposed navigation method.

Accuracy of Cardiac Output by Nine Different Pulse Contour Algorithms in Cardiac Surgery Patients: A Comparison with Transpulmonary Thermodilution.

PubMed

Broch, Ole; Bein, Berthold; Gruenewald, Matthias; Masing, Sarah; Huenges, Katharina; Haneya, Assad; Steinfath, Markus; Renner, Jochen

2016-01-01

Objective. Today, there exist several different pulse contour algorithms for calculation of cardiac output (CO). The aim of the present study was to compare the accuracy of nine different pulse contour algorithms with transpulmonary thermodilution before and after cardiopulmonary bypass (CPB). Methods. Thirty patients scheduled for elective coronary surgery were studied before and after CPB. A passive leg raising maneuver was also performed. Measurements included CO obtained by transpulmonary thermodilution (CO TPTD ) and by nine pulse contour algorithms (CO X1-9 ). Calibration of pulse contour algorithms was performed by esophageal Doppler ultrasound after induction of anesthesia and 15 min after CPB. Correlations, Bland-Altman analysis, four-quadrant, and polar analysis were also calculated. Results. There was only a poor correlation between CO TPTD and CO X1-9 during passive leg raising and in the period before and after CPB. Percentage error exceeded the required 30% limit. Four-quadrant and polar analysis revealed poor trending ability for most algorithms before and after CPB. The Liljestrand-Zander algorithm revealed the best reliability. Conclusions. Estimation of CO by nine different pulse contour algorithms revealed poor accuracy compared with transpulmonary thermodilution. Furthermore, the less-invasive algorithms showed an insufficient capability for trending hemodynamic changes before and after CPB. The Liljestrand-Zander algorithm demonstrated the highest reliability. This trial is registered with NCT02438228 (ClinicalTrials.gov).

Childhood clumsiness and peer victimization: a case–control study of psychiatric patients

PubMed Central

2013-01-01

Background Poor motor and social skills as well as peer victimization are commonly reported in both ADHD and autism spectrum disorder. Positive relationships between poor motor and poor social skills, and between poor social skills and peer victimization, are well documented, but the relationship between poor motor skills and peer victimization has not been studied in psychiatric populations. Method 277 patients (133 males, 144 females), mean age 31 years, investigated for ADHD or autism spectrum disorder in adulthood and with normal intelligence, were interviewed about childhood peer victimization and examined for gross motor skills. The parents completed a comprehensive questionnaire on childhood problems, the Five to Fifteen. The Five to Fifteen is a validated questionnaire with 181 statements that covers various symptoms in childhood across eight different domains, one of them targeting motor skills. Regression models were used to evaluate the relationship between motor skills and the risk and duration of peer victimization, adjusted for sex and diagnosis. Results Victims were described as more clumsy in childhood than their non-victimized counterparts. A significant independent association was found between reportedly poor childhood gross motor skills and peer victimization (adjusted odds ratio: 2.97 [95% confidence interval: 1.46-6.07], n = 235, p = 0.003). In adulthood, the victimized group performed worse on vertical jumps, a gross motor task, and were lonelier. Other factors that were expected to be associated with peer victimization were not found in this highly selected group. Conclusion Poor gross motor skills constitute a strong and independent risk factor for peer victimization in childhood, regardless of sex, childhood psychiatric care and diagnosis. PMID:23442984

STAR-GALAXY CLASSIFICATION IN MULTI-BAND OPTICAL IMAGING

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

Fadely, Ross; Willman, Beth; Hogg, David W.

2012-11-20

Ground-based optical surveys such as PanSTARRS, DES, and LSST will produce large catalogs to limiting magnitudes of r {approx}> 24. Star-galaxy separation poses a major challenge to such surveys because galaxies-even very compact galaxies-outnumber halo stars at these depths. We investigate photometric classification techniques on stars and galaxies with intrinsic FWHM <0.2 arcsec. We consider unsupervised spectral energy distribution template fitting and supervised, data-driven support vector machines (SVMs). For template fitting, we use a maximum likelihood (ML) method and a new hierarchical Bayesian (HB) method, which learns the prior distribution of template probabilities from the data. SVM requires training datamore » to classify unknown sources; ML and HB do not. We consider (1) a best-case scenario (SVM{sub best}) where the training data are (unrealistically) a random sampling of the data in both signal-to-noise and demographics and (2) a more realistic scenario where training is done on higher signal-to-noise data (SVM{sub real}) at brighter apparent magnitudes. Testing with COSMOS ugriz data, we find that HB outperforms ML, delivering {approx}80% completeness, with purity of {approx}60%-90% for both stars and galaxies. We find that no algorithm delivers perfect performance and that studies of metal-poor main-sequence turnoff stars may be challenged by poor star-galaxy separation. Using the Receiver Operating Characteristic curve, we find a best-to-worst ranking of SVM{sub best}, HB, ML, and SVM{sub real}. We conclude, therefore, that a well-trained SVM will outperform template-fitting methods. However, a normally trained SVM performs worse. Thus, HB template fitting may prove to be the optimal classification method in future surveys.« less

Low thermal budget annealing technique for high performance amorphous In-Ga-ZnO thin film transistors

NASA Astrophysics Data System (ADS)

Shin, Joong-Won; Cho, Won-Ju

2017-07-01

In this paper, we investigate a low thermal budget post-deposition-annealing (PDA) process for amorphous In-Ga-ZnO (a-IGZO) oxide semiconductor thin-film-transistors (TFTs). To evaluate the electrical characteristics and reliability of the TFTs after the PDA process, microwave annealing (MWA) and rapid thermal annealing (RTA) methods were applied, and the results were compared with those of the conventional annealing (CTA) method. The a-IGZO TFTs fabricated with as-deposited films exhibited poor electrical characteristics; however, their characteristics were improved by the proposed PDA process. The CTA-treated TFTs had excellent electrical properties and stability, but the CTA method required high temperatures and long processing times. In contrast, the fabricated RTA-treated TFTs benefited from the lower thermal budget due to the short process time; however, they exhibited poor stability. The MWA method uses a low temperature (100 °C) and short annealing time (2 min) because microwaves transfer energy directly to the substrate, and this method effectively removed the defects in the a-IGZO TFTs. Consequently, they had a higher mobility, higher on-off current ratio, lower hysteresis voltage, lower subthreshold swing, and higher interface trap density than TFTs treated with CTA or RTA, and exhibited excellent stability. Based on these results, low thermal budget MWA is a promising technology for use on various substrates in next generation displays.

Iron deficiency chlorosis in plants as related to Fe sources in soil

NASA Astrophysics Data System (ADS)

Díaz, I.; Delgado, A.; de Santiago, A.; del Campillo, M. C.; Torrent, J.

2012-04-01

Iron deficiency chlorosis (IDC) is a relevant agricultural problem in many areas of the World where calcareous soils are dominant. Although this problem has been traditionally ascribed to the pH-buffering effect of soil carbonates, the content and type of Fe oxides in soil contribute to explain Fe uptake by plants and the incidence of this problem. During the last two decades, it has been demonstrated Fe extraction with oxalate, related to the content of poorly crystalline Fe oxides, was well-correlated with the chlorophyll content of plants and thus with the incidence of IDC. This reveals the contribution of poorly crystalline Fe oxides in soil to Fe availability to plants in calcareous soils, previously shown in microcosm experiments using ferrihydrite as Fe source in the growing media. In order to supply additional information about the contribution of Fe sources in soil to explain the incidence of IDC and to perform accurate methods to predict it, a set of experiments involving different methods to extract soil Fe and plant cultivation in pots to correlate amounts of extracted Fe with the chlorophyll content of plants (measured using the SPAD chlorophyll meter) were performed. The first experiment involved 21 soils and white lupin cultivation, sequential Fe extraction in soil to study Fe forms, and single extractions (DTPA, rapid oxalate and non-buffered hydroxylamine). After that, a set of experiments in pot involving growing of grapevine rootstocks, chickpea, and sunflower were performed, although in this case only single extractions in soil were done. The Fe fraction more closely related to chlorophyll content in plants (r = 0.5, p < 0.05) was the citrate + ascorbate (CA) extraction, which was the fraction that releases most of the Fe related to poorly crystalline Fe oxides, thus revealing the key role of these compounds in Fe supply to plants. Fe extracted with CA was more correlated with chlorophyll content in plants that oxalate extractable Fe, probably due to a more selective dissolution of poorly crystalline oxides by the former extractant. In general terms, the best correlation between extractable Fe and chlorophyll content in plants was observed with hydroxylamine, which explained from 21 to 72 % of the variance observed in chlorophyll content in plants, greater than the variance explained by the rapid oxalate (11 to 60 %, not always significant) or the classical active calcium carbonate content determination (6 to 56 %, not always significant). Extraction with DTPA provided the worse results, explaining from 18 to 36 % of the variance in chlorophyll content in plants. The good predictive value of the hydroxylamine extraction was explained by its correlation with Fe in poorly crystalline Fe oxides (estimated as CA-extractable Fe) and by its negative correlation with the active calcium carbonate content of soils.

Subtyping children with developmental coordination disorder based on physical fitness outcomes.

PubMed

Aertssen, Wendy; Bonney, Emmanuel; Ferguson, Gillian; Smits-Engelsman, Bouwien

2018-05-28

Children with Developmental Coordination Disorder (DCD) are known to have poor physical fitness. However, differentiating homogenous subgroups of DCD using fitness performance has not yet been established. Therefore the purpose of this study was to identify subtypes in children with and without DCD using measures of physical fitness. Children (aged 6-10 years, n = 217) constituted the sample for this study. They were assessed on 1) aerobic fitness (20m Shuttle Run test), 2) anaerobic fitness (Muscle Power Sprint Test), 3) isometric muscle strength (handheld dynamometry) 4) functional upper and lower body strength (Functional Strength Measurement) and 5) motor coordination [Movement Assessment Battery for Children-2nd edition (MABC-2) test]. The Ward method was used to identify the various clusters. Five subtypes emerged in the entire sample. In the typically developing (TD) children mainly 2 subtypes (number 5 and 2) were found containing 89% of the TD children (n = 55), with the largest group demonstrating above average performance on all measures (cluster 5). Children in subtype 2 had just above average motor coordination and good aerobic fitness but lower muscle strength. Subtypes 1, 3 and 4 were clearly "DCD" clusters, however they showed difference in fitness performance. Subtype 1 contained children with DCD who showed poor performance on all fitness outcomes (n = 45). Children with DCD in subtype 3 had poor aerobic but average strength and anaerobic fitness (n = 48). Subtype 4 contained children with DCD (n = 45) who had good muscle strength and anaerobic fitness. Of these, 36% were at risk of DCD while 24% had definite motor coordination problems. Our findings indicate that children with and without DCD demonstrate heterogeneous physical fitness profiles. The majority of the children (66%) with DCD belonged to subtypes with lower fitness performance. Further studies are needed to confirm these findings in other samples of DCD children. Copyright © 2018 Elsevier B.V. All rights reserved.

Why Rural Community Day Secondary Schools Students' Performance in Physical Science Examinations Is Poor in Lilongwe Rural West Education District in Malawi

ERIC Educational Resources Information Center

Mlangeni, Angstone Noel J. Thembachako; Chiotha, Sosten Staphael

2015-01-01

A study was conducted to investigate factors that affect students' poor performance in physical science examinations at Malawi School Certificate of Education and Junior Certificate of Education levels in Community day secondary schools (CDSS) in Lilongwe Rural West Education District in Malawi. Students' performance was collected from schools'…

Is Self-Worth Protection Best Regarded as Intentional Self-Handicapping Behaviour or an Outcome of Choking under Pressure?

ERIC Educational Resources Information Center

Thompson, Ted; Dinnel, Dale L.

2007-01-01

Self-worth protective students characteristically perform poorly when they anticipate that poor performance is likely to reveal low ability, yet perform well in situations that involve little threat to self-worth. The present study sought a further understanding of this variable pattern of achievement, assessing two possibilities: (1) that the…

Advancing hypoxic training in team sports: from intermittent hypoxic training to repeated sprint training in hypoxia.

PubMed

Faiss, Raphaël; Girard, Olivier; Millet, Grégoire P

2013-12-01

Over the past two decades, intermittent hypoxic training (IHT), that is, a method where athletes live at or near sea level but train under hypoxic conditions, has gained unprecedented popularity. By adding the stress of hypoxia during 'aerobic' or 'anaerobic' interval training, it is believed that IHT would potentiate greater performance improvements compared to similar training at sea level. A thorough analysis of studies including IHT, however, leads to strikingly poor benefits for sea-level performance improvement, compared to the same training method performed in normoxia. Despite the positive molecular adaptations observed after various IHT modalities, the characteristics of optimal training stimulus in hypoxia are still unclear and their functional translation in terms of whole-body performance enhancement is minimal. To overcome some of the inherent limitations of IHT (lower training stimulus due to hypoxia), recent studies have successfully investigated a new training method based on the repetition of short (<30 s) 'all-out' sprints with incomplete recoveries in hypoxia, the so-called repeated sprint training in hypoxia (RSH). The aims of the present review are therefore threefold: first, to summarise the main mechanisms for interval training and repeated sprint training in normoxia. Second, to critically analyse the results of the studies involving high-intensity exercises performed in hypoxia for sea-level performance enhancement by differentiating IHT and RSH. Third, to discuss the potential mechanisms underpinning the effectiveness of those methods, and their inherent limitations, along with the new research avenues surrounding this topic.

A Divergence Median-based Geometric Detector with A Weighted Averaging Filter

NASA Astrophysics Data System (ADS)

Hua, Xiaoqiang; Cheng, Yongqiang; Li, Yubo; Wang, Hongqiang; Qin, Yuliang

2018-01-01

To overcome the performance degradation of the classical fast Fourier transform (FFT)-based constant false alarm rate detector with the limited sample data, a divergence median-based geometric detector on the Riemannian manifold of Heimitian positive definite matrices is proposed in this paper. In particular, an autocorrelation matrix is used to model the correlation of sample data. This method of the modeling can avoid the poor Doppler resolution as well as the energy spread of the Doppler filter banks result from the FFT. Moreover, a weighted averaging filter, conceived from the philosophy of the bilateral filtering in image denoising, is proposed and combined within the geometric detection framework. As the weighted averaging filter acts as the clutter suppression, the performance of the geometric detector is improved. Numerical experiments are given to validate the effectiveness of our proposed method.

Multi-stage classification method oriented to aerial image based on low-rank recovery and multi-feature fusion sparse representation.

PubMed

Ma, Xu; Cheng, Yongmei; Hao, Shuai

2016-12-10

Automatic classification of terrain surfaces from an aerial image is essential for an autonomous unmanned aerial vehicle (UAV) landing at an unprepared site by using vision. Diverse terrain surfaces may show similar spectral properties due to the illumination and noise that easily cause poor classification performance. To address this issue, a multi-stage classification algorithm based on low-rank recovery and multi-feature fusion sparse representation is proposed. First, color moments and Gabor texture feature are extracted from training data and stacked as column vectors of a dictionary. Then we perform low-rank matrix recovery for the dictionary by using augmented Lagrange multipliers and construct a multi-stage terrain classifier. Experimental results on an aerial map database that we prepared verify the classification accuracy and robustness of the proposed method.

A step toward development of printable dosage forms for poorly soluble drugs.

PubMed

Raijada, Dhara; Genina, Natalja; Fors, Daniela; Wisaeus, Erik; Peltonen, Jouko; Rantanen, Jukka; Sandler, Niklas

2013-10-01

The purpose of this study was to formulate printable dosage forms for a poorly soluble drug (piroxicam; PRX) and to gain understanding of critical parameters to be considered during development of such dosage forms. Liquid formulations of PRX were printed on edible paper using piezoelectric inkjet printing (PIJ) and impression printing (flexography). The printed dosage forms were characterized using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and the amount of drug was determined using high-performance liquid chromatography. Solutions of PRX in polyethylene glycol 400 (PEG-400):ethanol (40:60) and in PEG-400 were found to be optimal formulations for PIJ and flexography, respectively. SEM-EDX analysis revealed no visible solid particles on the printed dosage forms indicating the drug most likely remained in solution after printing. More accurate drug deposition was obtained by PIJ as compared with flexography. More than 90% drug release was achieved within 5 min regardless of printing method used. The solubility of drug in solvents/cosolvents, rheological properties of formulations, properties of substrate, feasibility and accuracy of the printing methods, and detection limit of analytical techniques for characterization of printed dosage forms are some of the concerns that need to be addressed for development of printable dosage forms of poorly soluble drugs. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

Measuring and understanding motivation among community health workers in rural health facilities in India-a mixed method study.

PubMed

Tripathy, Jaya Prasad; Goel, Sonu; Kumar, Ajay M V

2016-08-09

Motivated human resource is the key to improve health system performance and retention of health workers. There is scanty literature on measuring motivation of health workers in India. Thus, the objective of this study was to measure and identify important aspects of health workers' motivation in North India. A mixed method study design was adopted. Under the quantitative component, we interviewed randomly selected 62 community health workers (CHWs) in 18 sub-centres in two blocks of District Ambala, Haryana, India using a structured motivation scale. In-depth interviews were also carried out with 18 CHWs to explore the sources of motivation. The age of respondents and training in the past 12 months were found to be significantly associated with motivation. Job burnout, poor personal health, job insecurity and less career development opportunities were the individual level de-motivators, whereas not being able to fulfil family roles and poor supportive supervision were identified as environmental factors for poor motivation. Love for work, and financial incentives were individual level motivators, while community support and recognition, organizational commitment and pride, regular training were identified as environmental level motivators. Non-financial motivators such as interpersonal relations, family support, skill and career development opportunities require more attention. Regular need-based training is essential to maintain high levels of motivation.

Predictive factors for lymph node metastasis in poorly differentiated early gastric cancer and their impact on the surgical strategy

PubMed Central

Li, Hua; Lu, Ping; Lu, Yang; Liu, Cai-Gang; Xu, Hui-Mian; Wang, Shu-Bao; Chen, Jun-Qing

2008-01-01

AIM: To identify the predictive clinicopathological factors for lymph node metastasis (LNM) in poorly differentiated early gastric cancer (EGC) and to further expand the possibility of using endoscopic mucosal resection (EMR) for the treatment of poorly differentiated EGC. METHODS: Data were collected from 85 poorly-differentiated EGC patients who were surgically treated. Association between the clinicopathological factors and the presence of LNM was retrospectively analyzed by univariate and multivariate logistic regression analyses. RESULTS: Univariate analysis showed that tumor size (OR = 5.814, 95% CI = 1.050 - 32.172, P = 0.044), depth of invasion (OR = 10.763, 95% CI = 1.259 - 92.026, P = 0.030) and lymphatic vessel involvement (OR = 61.697, 95% CI = 2.144 - 175.485, P = 0.007) were the significant and independent risk factors for LNM. The LNM rate was 5.4%, 42.9% and 50%, respectively, in poorly differentiated EGC patients with one, two and three of the risk factors, respectively. No LNM was found in 25 patients without the three risk factors. Forty-four lymph nodes were found to have metastasis, 29 (65.9%) and 15 (34.1%) of the lymph nodes involved were within N1 and beyond N1, respectively, in 12 patients with LNM. CONCLUSION: Endoscopic mucosal resection alone may be sufficient to treat poorly differentiated intramucosal EGC (≤ 2.0 cm in diameter) with no histologically-confirmed lymphatic vessel involvement. When lymphatic vessels are involved, lymph node dissection beyond limited (D1) dissection or D1+ lymph node dissection should be performed depending on the tumor location. PMID:18636670

Visual acuity and visual skills in Malaysian children with learning disabilities

PubMed Central

Muzaliha, Mohd-Nor; Nurhamiza, Buang; Hussein, Adil; Norabibas, Abdul-Rani; Mohd-Hisham-Basrun, Jaafar; Sarimah, Abdullah; Leo, Seo-Wei; Shatriah, Ismail

2012-01-01

Background: There is limited data in the literature concerning the visual status and skills in children with learning disabilities, particularly within the Asian population. This study is aimed to determine visual acuity and visual skills in children with learning disabilities in primary schools within the suburban Kota Bharu district in Malaysia. Methods: We examined 1010 children with learning disabilities aged between 8–12 years from 40 primary schools in the Kota Bharu district, Malaysia from January 2009 to March 2010. These children were identified based on their performance in a screening test known as the Early Intervention Class for Reading and Writing Screening Test conducted by the Ministry of Education, Malaysia. Complete ocular examinations and visual skills assessment included near point of convergence, amplitude of accommodation, accommodative facility, convergence break and recovery, divergence break and recovery, and developmental eye movement tests for all subjects. Results: A total of 4.8% of students had visual acuity worse than 6/12 (20/40), 14.0% had convergence insufficiency, 28.3% displayed poor accommodative amplitude, and 26.0% showed signs of accommodative infacility. A total of 12.1% of the students had poor convergence break, 45.7% displayed poor convergence recovery, 37.4% showed poor divergence break, and 66.3% were noted to have poor divergence recovery. The mean horizontal developmental eye movement was significantly prolonged. Conclusion: Although their visual acuity was satisfactory, nearly 30% of the children displayed accommodation problems including convergence insufficiency, poor accommodation, and accommodative infacility. Convergence and divergence recovery are the most affected visual skills in children with learning disabilities in Malaysia. PMID:23055674

Long-running telemedicine networks delivering humanitarian services: experience, performance and scientific output

PubMed Central

Geissbuhler, Antoine; Jethwani, Kamal; Kovarik, Carrie; Person, Donald A; Vladzymyrskyy, Anton; Zanaboni, Paolo; Zolfo, Maria

2012-01-01

Abstract Objective To summarize the experience, performance and scientific output of long-running telemedicine networks delivering humanitarian services. Methods Nine long-running networks – those operating for five years or more– were identified and seven provided detailed information about their activities, including performance and scientific output. Information was extracted from peer-reviewed papers describing the networks’ study design, effectiveness, quality, economics, provision of access to care and sustainability. The strength of the evidence was scored as none, poor, average or good. Findings The seven networks had been operating for a median of 11 years (range: 5–15). All networks provided clinical tele-consultations for humanitarian purposes using store-and-forward methods and five were also involved in some form of education. The smallest network had 15 experts and the largest had more than 500. The clinical caseload was 50 to 500 cases a year. A total of 59 papers had been published by the networks, and 44 were listed in Medline. Based on study design, the strength of the evidence was generally poor by conventional standards (e.g. 29 papers described non-controlled clinical series). Over half of the papers provided evidence of sustainability and improved access to care. Uncertain funding was a common risk factor. Conclusion Improved collaboration between networks could help attenuate the lack of resources reported by some networks and improve sustainability. Although the evidence base is weak, the networks appear to offer sustainable and clinically useful services. These findings may interest decision-makers in developing countries considering starting, supporting or joining similar telemedicine networks. PMID:22589567

[Gender reassignment surgery in transsexualism from a urological perspective].

PubMed

Althaus, Peter

2006-01-01

The surgical treatment of transsexual patients can barely be called satisfactory. Poor quality surgical operations cause the life of the patients so treated to become unhappy. Transsexual surgery should only be performed in centres where a sufficient amount of experience has been gathered, and--what is equally important--an understanding amounting to affinity exists with the problem of transsexualism. There is a great need for better treatment methods. The present situation is far from being optimal.

Single-locus species delimitation: a test of the mixed Yule-coalescent model, with an empirical application to Philippine round-leaf bats.

PubMed

Esselstyn, Jacob A; Evans, Ben J; Sedlock, Jodi L; Anwarali Khan, Faisal Ali; Heaney, Lawrence R

2012-09-22

Prospects for a comprehensive inventory of global biodiversity would be greatly improved by automating methods of species delimitation. The general mixed Yule-coalescent (GMYC) was recently proposed as a potential means of increasing the rate of biodiversity exploration. We tested this method with simulated data and applied it to a group of poorly known bats (Hipposideros) from the Philippines. We then used echolocation call characteristics to evaluate the plausibility of species boundaries suggested by GMYC. In our simulations, GMYC performed relatively well (errors in estimated species diversity less than 25%) when the product of the haploid effective population size (N(e)) and speciation rate (SR; per lineage per million years) was less than or equal to 10(5), while interspecific variation in N(e) was twofold or less. However, at higher but also biologically relevant values of N(e) × SR and when N(e) varied tenfold among species, performance was very poor. GMYC analyses of mitochondrial DNA sequences from Philippine Hipposideros suggest actual diversity may be approximately twice the current estimate, and available echolocation call data are mostly consistent with GMYC delimitations. In conclusion, we consider the GMYC model useful under some conditions, but additional information on N(e), SR and/or corroboration from independent character data are needed to allow meaningful interpretation of results.

Advancing haemostasis automation--successful implementation of robotic centrifugation and sample processing in a tertiary service hospital.

PubMed

Sédille-Mostafaie, Nazanin; Engler, Hanna; Lutz, Susanne; Korte, Wolfgang

2013-06-01

Laboratories today face increasing pressure to automate operations due to increasing workloads and the need to reduce expenditure. Few studies to date have focussed on the laboratory automation of preanalytical coagulation specimen processing. In the present study, we examined whether a clinical chemistry automation protocol meets the preanalytical requirements for the analyses of coagulation. During the implementation of laboratory automation, we began to operate a pre- and postanalytical automation system. The preanalytical unit processes blood specimens for chemistry, immunology and coagulation by automated specimen processing. As the production of platelet-poor plasma is highly dependent on optimal centrifugation, we examined specimen handling under different centrifugation conditions in order to produce optimal platelet deficient plasma specimens. To this end, manually processed models centrifuged at 1500 g for 5 and 20 min were compared to an automated centrifugation model at 3000 g for 7 min. For analytical assays that are performed frequently enough to be targets for full automation, Passing-Bablok regression analysis showed close agreement between different centrifugation methods, with a correlation coefficient between 0.98 and 0.99 and a bias between -5% and +6%. For seldom performed assays that do not mandate full automation, the Passing-Bablok regression analysis showed acceptable to poor agreement between different centrifugation methods. A full automation solution is suitable and can be recommended for frequent haemostasis testing.

Simultaneous measurement of proguanil and its metabolites in human plasma and urine by reversed-phase high-performance liquid chromatography, and its preliminary application in relation to genetically determined S-mephenytoin 4'-hydroxylation status.

PubMed

Kusaka, M; Setiabudy, R; Chiba, K; Ishizaki, T

1996-02-01

A simple high-performance liquid chromatographic (HPLC) assay method was developed for the measurement of proguanil (PG) and its major metabolites, cycloguanil (CG) and 4-chlorophenyl-biguanide (CPB), in human plasma and urine. The assay allowed the simultaneous determination of all analytes in 1 ml of plasma or 0.1 ml of urine. The detection limits of PG, CG, and CPB, defined as the signal-to-noise ratio of 3, were 1 and 5 ng/ml for plasma and urine samples, respectively. Recoveries of the analytes and the internal standard (pyrimethamine) were > 62% from plasma and > 77% from urine. Intra-assay and interassay coefficients of variation for all analytes in plasma and urine were < 10% except for the values of CG and CPB, which ranged from 10% to 15% at one or two concentrations among 4-5 concentrations studied. The clinical applicability of the method was assessed by the preliminary pharmacokinetic study of PG, CG, and CPB in six healthy volunteers with the individually known phenotypes (extensive and poor metabolizers) of S-mephenytoin 4'-hydroxylation, suggesting that individuals with a poor metabolizer phenotype of S-mephenytoin have a much lower capacity to bioactivate PG to CG compared with the extensive metabolizers.

Hybrid quantum and molecular mechanics embedded cluster models for chemistry on silicon and silicon carbide surfaces

NASA Astrophysics Data System (ADS)

Shoemaker, James Richard

Fabrication of silicon carbide (SiC) semiconductor devices are of interest for aerospace applications because of their high-temperature tolerance. Growth of an insulating SiO2 layer on SiC by oxidation is a poorly understood process, and sometimes produces interface defects that degrade device performance. Accurate theoretical models of surface chemistry, using quantum mechanics (QM), do not exist because of the huge computational cost of solving Schrodinger's equation for a molecular cluster large enough to represent a surface. Molecular mechanics (MM), which describes a molecule as a collection of atoms interacting through classical potentials, is a fast computational method, good at predicting molecular structure, but cannot accurately model chemical reactions. A new hybrid QM/MM computational method for surface chemistry was developed and applied to silicon and SiC surfaces. The addition of MM steric constraints was shown to have a large effect on the energetics of O atom adsorption on SiC. Adsorption of O atoms on Si-terminated SiC(111) favors above surface sites, in contrast to Si(111), but favors subsurface adsorption sites on C- terminated SiC(111). This difference, and the energetics of C atom etching via CO2 desorption, can explain the observed poor performance of SiC devices in which insulating layers were grown on C-terminated surfaces.

Morphology-dependent optical absorption and conduction properties of photoelectrochemical photocatalysts for H2 production: A case study

NASA Astrophysics Data System (ADS)

Huda, Muhammad N.; Turner, John A.

2010-06-01

Efficient photoelectrochemical H2 production by solar irradiation depends not only on the photocatalyst's band gap and its band-edge positions but also on the detailed electronic nature of the bands, such as the localization or delocalization of the band edges and their orbital characteristics. These determine the carrier transport properties, reactivity, light absorption strength, etc. and significantly impact the material's efficiency as a photoconverter. The localization or delocalization of the band edges may arise either due to the orbital nature of the bands or the structural morphology of the material. A recent experimental report on a photocatalyst based on s /p orbitals showed very poor performance for H2 production despite the delocalized nature of the s /p bands as compared to the d-bands of transition metal oxides. It is then important to examine whether this poor performance is inherent to these materials or rather arises from some experimental limitations. A theoretical analysis by first-principle methods is well suited to shed light on this question.

Ascertainment bias from imputation methods evaluation in wheat.

PubMed

Brandariz, Sofía P; González Reymúndez, Agustín; Lado, Bettina; Malosetti, Marcos; Garcia, Antonio Augusto Franco; Quincke, Martín; von Zitzewitz, Jarislav; Castro, Marina; Matus, Iván; Del Pozo, Alejandro; Castro, Ariel J; Gutiérrez, Lucía

2016-10-04

Whole-genome genotyping techniques like Genotyping-by-sequencing (GBS) are being used for genetic studies such as Genome-Wide Association (GWAS) and Genomewide Selection (GS), where different strategies for imputation have been developed. Nevertheless, imputation error may lead to poor performance (i.e. smaller power or higher false positive rate) when complete data is not required as it is for GWAS, and each marker is taken at a time. The aim of this study was to compare the performance of GWAS analysis for Quantitative Trait Loci (QTL) of major and minor effect using different imputation methods when no reference panel is available in a wheat GBS panel. In this study, we compared the power and false positive rate of dissecting quantitative traits for imputed and not-imputed marker score matrices in: (1) a complete molecular marker barley panel array, and (2) a GBS wheat panel with missing data. We found that there is an ascertainment bias in imputation method comparisons. Simulating over a complete matrix and creating missing data at random proved that imputation methods have a poorer performance. Furthermore, we found that when QTL were simulated with imputed data, the imputation methods performed better than the not-imputed ones. On the other hand, when QTL were simulated with not-imputed data, the not-imputed method and one of the imputation methods performed better for dissecting quantitative traits. Moreover, larger differences between imputation methods were detected for QTL of major effect than QTL of minor effect. We also compared the different marker score matrices for GWAS analysis in a real wheat phenotype dataset, and we found minimal differences indicating that imputation did not improve the GWAS performance when a reference panel was not available. Poorer performance was found in GWAS analysis when an imputed marker score matrix was used, no reference panel is available, in a wheat GBS panel.

Evaluation of trapping-web designs

USGS Publications Warehouse

Lukacs, P.M.; Anderson, D.R.; Burnham, K.P.

2005-01-01

The trapping web is a method for estimating the density and abundance of animal populations. A Monte Carlo simulation study is performed to explore performance of the trapping web for estimating animal density under a variety of web designs and animal behaviours. The trapping performs well when animals have home ranges, even if the home ranges are large relative to trap spacing. Webs should contain at least 90 traps. Trapping should continue for 5-7 occasions. Movement rates have little impact on density estimates when animals are confined to home ranges. Estimation is poor when animals do not have home ranges and movement rates are rapid. The trapping web is useful for estimating the density of animals that are hard to detect and occur at potentially low densities. ?? CSIRO 2005.

Combining approaches to on-line handwriting information retrieval

NASA Astrophysics Data System (ADS)

Peña Saldarriaga, Sebastián; Viard-Gaudin, Christian; Morin, Emmanuel

2010-01-01

In this work, we propose to combine two quite different approaches for retrieving handwritten documents. Our hypothesis is that different retrieval algorithms should retrieve different sets of documents for the same query. Therefore, significant improvements in retrieval performances can be expected. The first approach is based on information retrieval techniques carried out on the noisy texts obtained through handwriting recognition, while the second approach is recognition-free using a word spotting algorithm. Results shows that for texts having a word error rate (WER) lower than 23%, the performances obtained with the combined system are close to the performances obtained on clean digital texts. In addition, for poorly recognized texts (WER > 52%), an improvement of nearly 17% can be observed with respect to the best available baseline method.

Visible-light-driven photoelectrochemical and photocatalytic performances of Cr-doped SrTiO3/TiO2 heterostructured nanotube arrays.

PubMed

Jiao, Zhengbo; Chen, Tao; Xiong, Jinyan; Wang, Teng; Lu, Gongxuan; Ye, Jinhua; Bi, Yingpu

2013-01-01

Well-aligned TiO2 nanotube arrays have become of increasing significance because of their unique highly ordered array structure, high specific surface area, unidirectional charge transfer and transportation features. However, their poor visible light utilization as well as the high recombination rate of photoexcited electron-hole pairs greatly limited their practical applications. Herein, we demonstrate the fabrication of visible-light-responsive heterostructured Cr-doped SrTiO3/TiO2 nanotube arrays by a simple hydrothermal method, which facilitate efficient charge separation and thus improve the photoelectrochemical as well as photocatalytic performances.

SETI low-frequency feed design study for DSS 24

NASA Technical Reports Server (NTRS)

Stanton, P. H.; Lee, P. R.

1992-01-01

The Search for Extraterrestrial Intelligence Sky Survey project requires operation from 1 to 10 GHz on the beam waveguide (BWG) antenna DSS 24. The BWG reflectors are undersized in the 1- to 3.02-GHz range, resulting in poor performance. Horn designs and a method for implementing 1- to 3.02-GHz operation on DSS 24 are presented. A combination of a horn and a shaped feed reflector placed above the main reflector is suggested. The horn and feed reflector could be hidden in the RF shadow of the subreflector and struts. Results from computer analysis of this design indicate that adequate performance could be achieved.

Poor decision-making by chronic marijuana users is associated with decreased functional responsiveness to negative consequences.

PubMed

Wesley, Michael J; Hanlon, Colleen A; Porrino, Linda J

2011-01-30

Chronic marijuana users (MJ Users) perform poorly on the Iowa Gambling Task (IGT), a complex decision-making task in which monetary wins and losses guide strategy development. This functional magnetic resonance imaging (MRI) study sought to determine if the poor performance of MJ Users was related to differences in brain activity while evaluating wins and losses during the strategy development phase of the IGT. MJ Users (16) and Controls (16) performed a modified IGT in an MRI scanner. Performance was tracked and functional activity in response to early wins and losses was examined. While the MJ Users continued to perform poorly at the end of the task, there was no difference in group performance during the initial strategy development phase. During this phase, before the emergence of behavioral differences, Controls exhibited significantly greater activity in response to losses in the anterior cingulate cortex, medial frontal cortex, precuneus, superior parietal lobe, occipital lobe and cerebellum as compared to MJ Users. Furthermore, in Controls, but not MJ Users, the functional response to losses in the anterior cingulate cortex, ventral medial prefrontal cortex and rostral prefrontal cortex positively correlated with performance over time. These data suggest MJ Users are less sensitive to negative feedback during strategy development. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Impact of familiar and unfamiliar settings on cooking task assessments in frail older adults with poor and preserved executive functions.

PubMed

Provencher, Véronique; Demers, Louise; Gagnon, Lise; Gélinas, Isabelle

2012-05-01

Hospitalized frail older patients are usually assessed for their ability to perform some daily living activities in a clinical setting prior to discharge. However, assessments that take place in this unfamiliar environment might not be as representative of their functional performance as assessments at home. This may be related to a decline in some cognitive components, such as executive functions (EF), which enable one to cope with new environments. This study thus aims to compare cooking task performance in familiar and unfamiliar settings in a population of frail older adults with poor and preserved EF. Thirty-seven frail older adults were assigned to one of two groups: poor EF or preserved EF. Participants performed two cooking tasks in familiar and unfamiliar settings, using a counterbalanced design. Their performance was assessed with a reliable tool based on observation of motor and process skills (Assessment of Motor and Process Skills). Thirty-three participants were retained for analysis. They demonstrated significantly better motor skills (F = 5.536; p = 0.025) and process skills (F = 8.149; p = 0.008) in the familiar setting. The difference between settings was particularly marked for process skills in participants with poor EF (F = 16.920; p < 0.001). This study suggests that a home setting may be preferable for a more accurate assessment of cooking task performance in frail older adults, especially those with poor EF. These findings highlight the risk of underestimating frail older adults' performance when assessed in an unfamiliar setting (e.g. hospital), which could lead to inefficient allocation of home care services.

Species delimitation using Bayes factors: simulations and application to the Sceloporus scalaris species group (Squamata: Phrynosomatidae).

PubMed

Grummer, Jared A; Bryson, Robert W; Reeder, Tod W

2014-03-01

Current molecular methods of species delimitation are limited by the types of species delimitation models and scenarios that can be tested. Bayes factors allow for more flexibility in testing non-nested species delimitation models and hypotheses of individual assignment to alternative lineages. Here, we examined the efficacy of Bayes factors in delimiting species through simulations and empirical data from the Sceloporus scalaris species group. Marginal-likelihood scores of competing species delimitation models, from which Bayes factor values were compared, were estimated with four different methods: harmonic mean estimation (HME), smoothed harmonic mean estimation (sHME), path-sampling/thermodynamic integration (PS), and stepping-stone (SS) analysis. We also performed model selection using a posterior simulation-based analog of the Akaike information criterion through Markov chain Monte Carlo analysis (AICM). Bayes factor species delimitation results from the empirical data were then compared with results from the reversible-jump MCMC (rjMCMC) coalescent-based species delimitation method Bayesian Phylogenetics and Phylogeography (BP&P). Simulation results show that HME and sHME perform poorly compared with PS and SS marginal-likelihood estimators when identifying the true species delimitation model. Furthermore, Bayes factor delimitation (BFD) of species showed improved performance when species limits are tested by reassigning individuals between species, as opposed to either lumping or splitting lineages. In the empirical data, BFD through PS and SS analyses, as well as the rjMCMC method, each provide support for the recognition of all scalaris group taxa as independent evolutionary lineages. Bayes factor species delimitation and BP&P also support the recognition of three previously undescribed lineages. In both simulated and empirical data sets, harmonic and smoothed harmonic mean marginal-likelihood estimators provided much higher marginal-likelihood estimates than PS and SS estimators. The AICM displayed poor repeatability in both simulated and empirical data sets, and produced inconsistent model rankings across replicate runs with the empirical data. Our results suggest that species delimitation through the use of Bayes factors with marginal-likelihood estimates via PS or SS analyses provide a useful and complementary alternative to existing species delimitation methods.

Frequency of and risk factors for poor cognitive performance in hemodialysis patients

USDA-ARS?s Scientific Manuscript database

There are few detailed data on cognition in patients undergoing dialysis. We evaluated the frequency of and risk factors for poor cognitive performance using detailed neurocognitive testing. In this cross-sectional cohort study, 314 hemodialysis patients from 6 Boston-area hemodialysis units underwe...

Confronting Poor Performance.

ERIC Educational Resources Information Center

Dennis, Bruce L.

Responsible and effective administrative leadership requires confronting those members of the teaching staff who are a negative influence on the institution. Importantly, the absence of expressed appreciation for good work can have a devastating impact on a principal's image if he or she suddenly begins to confront poor performances. Actually, the…

Perceptual impairment in face identification with poor sleep

PubMed Central

Beattie, Louise; Walsh, Darragh; McLaren, Jessica; Biello, Stephany M.

2016-01-01

Previous studies have shown impaired memory for faces following restricted sleep. However, it is not known whether lack of sleep impairs performance on face identification tasks that do not rely on recognition memory, despite these tasks being more prevalent in security and forensic professions—for example, in photo-ID checks at national borders. Here we tested whether poor sleep affects accuracy on a standard test of face-matching ability that does not place demands on memory: the Glasgow Face-Matching Task (GFMT). In Experiment 1, participants who reported sleep disturbance consistent with insomnia disorder show impaired accuracy on the GFMT when compared with participants reporting normal sleep behaviour. In Experiment 2, we then used a sleep diary method to compare GFMT accuracy in a control group to participants reporting poor sleep on three consecutive nights—and again found lower accuracy scores in the short sleep group. In both experiments, reduced face-matching accuracy in those with poorer sleep was not associated with lower confidence in their decisions, carrying implications for occupational settings where identification errors made with high confidence can have serious outcomes. These results suggest that sleep-related impairments in face memory reflect difficulties in perceptual encoding of identity, and point towards metacognitive impairment in face matching following poor sleep. PMID:27853547

The current role of direct vision internal urethrotomy and self-catheterization for anterior urethral strictures

PubMed Central

Dubey, Deepak

2011-01-01

Introduction: Direct visual internal urethrotomy (DVIU) followed by intermittent self-dilatation (ISD) is the most commonly performed intervention for urethral stricture disease. The objective of this paper is to outline the current scientific evidence supporting this approach for its use in the management of anterior urethral strictures. Materials and Methods: A Pubmed database search was performed with the words “internal urethrotomy” and “internal urethrotomy” self-catheterization. All papers dealing with this subject were scrutinized. Cross-references from the retrieved articles were also viewed. Only English language articles were included in the analyses. Studies were analyzed to identify predictors for success for DVIU. Results: Initial studies showed excellent outcomes with DVIU with success rates ranging from 50% to 85%. However, these studies reported only short-term results. Recent studies with longer followup have shown a poor success rate ranging from 6% to 28%. Stricture length and degree of fibrosis (luminal narrowing) were found to be predictors of response. Repeated urethrotomies were associated with poor results. Studies involving intermittent self-catheterization following DVIU have shown no role in short-term ISD with one study reporting beneficial effects if continued for more than a year. A significant number of studies have shown long-term complications with SC and high dropout rates. Conclusions: DVIU is associated with poor long-term cure rates. It remains as a treatment of first choice for bulbar urethral strictures <1 cm with minimal spongiofibrosis. There is no role for repeated urethrotomy as outcomes are uniformly poor. ISD, when used for more than a year on a weekly or biweekly basis may delay the onset of stricture recurrence. PMID:22022065

Relationship Between Poor Physical Function, Inflammatory Markers, and Comorbidities in HIV-Infected Women on Antiretroviral Therapy

PubMed Central

Harris, Ariana; Michaels, Daniel; Miciek, Renee; Storer, Thomas; Sebastiani, Paola; Montano, Monty

2014-01-01

Abstract Background: HIV-infected individuals may be at increased risk of poor physical function. Chronic inflammation has been associated with decreased physical function in the elderly and may also influence physical function in HIV-infected individuals. Methods: This cross-sectional study assessed physical function in 65 HIV-infected women aged 40 and older on stable antiretroviral treatment using the Short Physical Performance Battery (SPPB): a standardized test of balance, walking speed, and lower- extremity strength developed for elderly populations. The relationship between low SPPB score, selected demographic and medical characteristics, and high inflammatory biomarker profile was analyzed using Fisher's exact test and Wilcoxon rank sum test. Results: The median age of subjects was 49 years (interquartile range [IQR] 45–55), and the median CD4 T-cell count was 675 cells/mm3 (IQR 436–828). Thirteen subjects (20%) had a low SPPB score. Subjects with a low SPPB score were more likely to be cigarette smokers (p=0.03), had more medical comorbidities (p=0.01), and had higher levels of interleukin-6 (IL-6) (p<0.05). They also tended to be older (median age 55 vs. 48, p=0.06), more likely to have diabetes (p=0.07), and have higher levels of soluble tumor necrosis factor-1 (p=0.09). Conclusions: Twenty percent of women aged 40 and older with well-treated HIV had poor physical-function performance, which was associated with the high burden of comorbidities in this population and with increased IL-6. However, it is unclear from this cross-sectional study whether increased inflammation was related to poor physical function or to other factors, such as age and medical comorbidities. PMID:24219874

Bench-scale screening tests for a boiling sodium-potassium alloy solar receiver

NASA Astrophysics Data System (ADS)

Moreno, J. B.; Moss, T. A.

1993-06-01

Bench-scale tests were carried out in support of the design of a second-generation 75-kW(sub t) reflux pool-boiler solar receiver. The receiver will be made from Haynes Alloy 230 and will contain the sodium-potassium alloy NaK-78. The bench-scale tests used quartz lamp heated boilers to screen candidate boiling stabilization materials and methods at temperatures up to 750 degree C. Candidates that provided stable boiling were tested for hot-restart behavior. Poor stability was obtained with single 1/4-inch diameter patches of powdered metal hot press sintered onto the wetted side of the heat-input area. Laser-drilled and electric discharge machined cavities in the heated surface also performed poorly. Small additions of xenon, and heated-surface tilt out of the vertical, dramatically improved poor boiling stability; additions of helium or oxygen did not. The most stable boiling was obtained when the entire heat-input area was covered by a powdered-metal coating. The effect of heated-area size was assessed for one coating: at low incident fluxes, when even this coating performed poorly, increasing the heated-area size markedly improved boiling stability. Good hot-restart behavior was not observed with any candidate, although results were significantly better with added xenon in a boiler shortened from 3 to 2 feet. In addition to the screening tests, flash-radiography imaging of metal-vapor bubbles during boiling was attempted. Contrary to the Cole-Rohsenow correlation, these bubble-size estimates did not vary with pressure; instead they were constant, consistent with the only other alkali metal measurements, but about 1/2 their size.

Applying Multivariate Discrete Distributions to Genetically Informative Count Data.

PubMed

Kirkpatrick, Robert M; Neale, Michael C

2016-03-01

We present a novel method of conducting biometric analysis of twin data when the phenotypes are integer-valued counts, which often show an L-shaped distribution. Monte Carlo simulation is used to compare five likelihood-based approaches to modeling: our multivariate discrete method, when its distributional assumptions are correct, when they are incorrect, and three other methods in common use. With data simulated from a skewed discrete distribution, recovery of twin correlations and proportions of additive genetic and common environment variance was generally poor for the Normal, Lognormal and Ordinal models, but good for the two discrete models. Sex-separate applications to substance-use data from twins in the Minnesota Twin Family Study showed superior performance of two discrete models. The new methods are implemented using R and OpenMx and are freely available.

A two-step electrodialysis method for DNA purification from polluted metallic environmental samples.

PubMed

Rodríguez-Mejía, José Luis; Martínez-Anaya, Claudia; Folch-Mallol, Jorge Luis; Dantán-González, Edgar

2008-08-01

Extracting DNA from samples of polluted environments using standard methods often results in low yields of poor-quality material unsuited to subsequent manipulation and analysis by molecular biological techniques. Here, we report a novel two-step electrodialysis-based method for the extraction of DNA from environmental samples. This technique permits the rapid and efficient isolation of high-quality DNA based on its acidic nature, and without the requirement for phenol-chloroform-isoamyl alcohol cleanup and ethanol precipitation steps. Subsequent PCR, endonuclease restriction, and cloning reactions were successfully performed utilizing DNA obtained by electrodialysis, whereas some or all of these techniques failed using DNA extracted with two alternative methods. We also show that his technique is applicable to purify DNA from a range of polluted and nonpolluted samples.

A NEW LOG EVALUATION METHOD TO APPRAISE MESAVERDE RE-COMPLETION OPPORTUNITIES

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

Albert Greer

2003-09-11

Artificial intelligence tools, fuzzy logic and neural networks were used to evaluate the potential of the behind pipe Mesaverde formation in BMG's Mancos formation wells. A fractal geostatistical mapping algorithm was also used to predict Mesaverde production. Additionally, a conventional geological study was conducted. To date one Mesaverde completion has been performed. The Janet No.3 Mesaverde completion was non-economic. Both the AI method and the geostatistical methods predicted the failure of the Janet No.3. The Gavilan No.1 in the Mesaverde was completed during the course of the study and was an extremely good well. This well was not included inmore » the statistical dataset. The AI method predicted very good production while the fractal map predicted a poor producer.« less

The oral microbiome and human health.

PubMed

Yamashita, Yoshihisa; Takeshita, Toru

2017-01-01

In this brief review, we discuss our previous research on the relationship between the bacterial composition of salivary microbiota and periodontal disease. Analysis using a terminal restriction fragment length polymorphism method and an international comparison suggest that the predominance of the genera Prevotella and Veillonella in the salivary microbiota is attributable to periodontal disease conditions, and that the predominance of the genus Neisseria indicates healthy periodontal conditions. Furthermore, we recently used next-generation sequencing technology to perform a detailed large-scale analysis of the salivary microbiota. An important finding of that study was that high bacterial richness in the salivary microbiota was significantly associated with poor oral health, as indicated by decayed teeth, periodontitis, and poor oral hygiene. Another important result was that relative abundance of predominant bacteria in saliva was significantly associated with oral health-related conditions. Of the two different cohabiting groups of bacteria found in the salivary microbiota, a greater relative abundance of group I bacteria, which include Prevotella and Veillonella species, was associated with poor oral health, high body mass index, and old age. These findings suggest that the salivary microbiota reflects oral and systemic conditions.

AGREEMENT AND COVERAGE OF INDICATORS OF RESPONSE TO INTERVENTION: A MULTI-METHOD COMPARISON AND SIMULATION

PubMed Central

Fletcher, Jack M.; Stuebing, Karla K.; Barth, Amy E.; Miciak, Jeremy; Francis, David J.; Denton, Carolyn A.

2013-01-01

Purpose Agreement across methods for identifying students as inadequate responders or as learning disabled is often poor. We report (1) an empirical examination of final status (post-intervention benchmarks) and dual-discrepancy growth methods based on growth during the intervention and final status for assessing response to intervention; and (2) a statistical simulation of psychometric issues that may explain low agreement. Methods After a Tier 2 intervention, final status benchmark criteria were used to identify 104 inadequate and 85 adequate responders to intervention, with comparisons of agreement and coverage for these methods and a dual-discrepancy method. Factors affecting agreement were investigated using computer simulation to manipulate reliability, the intercorrelation between measures, cut points, normative samples, and sample size. Results Identification of inadequate responders based on individual measures showed that single measures tended not to identify many members of the pool of 104 inadequate responders. Poor to fair levels of agreement for identifying inadequate responders were apparent between pairs of measures In the simulation, comparisons across two simulated measures generated indices of agreement (kappa) that were generally low because of multiple psychometric issues inherent in any test. Conclusions Expecting excellent agreement between two correlated tests with even small amounts of unreliability may not be realistic. Assessing outcomes based on multiple measures, such as level of CBM performance and short norm-referenced assessments of fluency may improve the reliability of diagnostic decisions. PMID:25364090

DRAINWAT--Based Methods For Estimating Nitrogen Transport in Poorly Drained Watersheds

Treesearch

Devendra M. Amatya; George M. Chescheir; Glenn P. Fernandez; R. Wayne Skaggs; J.W. Gilliam

2004-01-01

Methods are needed to quantify effects of land use and management practices on nutrient and sediment loads at the watershed scale. Two methods were used to apply a DRAINMOD-based watershed-scale model (DRAINWAT) to estimate total nitrogen (N) transport from a poorly drained, forested watershed. In both methods, in-stream retention or losses of N were calculated with a...

The association of neighbourhood and individual social capital with consistent self-rated health: a longitudinal study in Brazilian pregnant and postpartum women

PubMed Central

2013-01-01

Background Social conditions, social relationships and neighbourhood environment, the components of social capital, are important determinants of health. The objective of this study was to investigate the association of neighbourhood and individual social capital with consistent self-rated health in women between the first trimester of pregnancy and six months postpartum. Methods A multilevel cohort study in 34 neighbourhoods was performed on 685 Brazilian women recruited at antenatal units in two cities in the State of Rio de Janeiro, Brazil. Self-rated health (SRH) was assessed in the 1st trimester of pregnancy (baseline) and six months after childbirth (follow-up). The participants were divided into two groups: 1. Good SRH – good SRH at baseline and follow-up, and, 2. Poor SRH – poor SRH at baseline and follow-up. Exploratory variables collected at baseline included neighbourhood social capital (neighbourhood-level variable), individual social capital (social support and social networks), demographic and socioeconomic characteristics, health-related behaviours and self-reported diseases. A hierarchical binomial multilevel analysis was performed to test the association between neighbourhood and individual social capital and SRH, adjusted for covariates. Results The Good SRH group reported higher scores of social support and social networks than the Poor SRH group. Although low neighbourhood social capital was associated with poor SRH in crude analysis, the association was not significant when individual socio-demographic variables were included in the model. In the final model, women reporting poor SRH both at baseline and follow-up had lower levels of social support (positive social interaction) [OR 0.82 (95% CI: 0.73-0.90)] and a lower likelihood of friendship social networks [OR 0.61 (95% CI: 0.37-0.99)] than the Good SRH group. The characteristics that remained associated with poor SRH were low level of schooling, Black and Brown ethnicity, more children, urinary infection and water plumbing outside the house. Conclusions Low individual social capital during pregnancy, considered here as social support and social network, was independently associated with poor SRH in women whereas neighbourhood social capital did not affect women’s SRH during pregnancy and the months thereafter. From pregnancy and up to six months postpartum, the effect of individual social capital explained better the consistency of SRH over time than neighbourhood social capital. PMID:23324161

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.

PANNZER2: a rapid functional annotation web server.

PubMed

Törönen, Petri; Medlar, Alan; Holm, Liisa

2018-05-08

The unprecedented growth of high-throughput sequencing has led to an ever-widening annotation gap in protein databases. While computational prediction methods are available to make up the shortfall, a majority of public web servers are hindered by practical limitations and poor performance. Here, we introduce PANNZER2 (Protein ANNotation with Z-scoRE), a fast functional annotation web server that provides both Gene Ontology (GO) annotations and free text description predictions. PANNZER2 uses SANSparallel to perform high-performance homology searches, making bulk annotation based on sequence similarity practical. PANNZER2 can output GO annotations from multiple scoring functions, enabling users to see which predictions are robust across predictors. Finally, PANNZER2 predictions scored within the top 10 methods for molecular function and biological process in the CAFA2 NK-full benchmark. The PANNZER2 web server is updated on a monthly schedule and is accessible at http://ekhidna2.biocenter.helsinki.fi/sanspanz/. The source code is available under the GNU Public Licence v3.

A Robust Statistics Approach to Minimum Variance Portfolio Optimization

NASA Astrophysics Data System (ADS)

Yang, Liusha; Couillet, Romain; McKay, Matthew R.

2015-12-01

We study the design of portfolios under a minimum risk criterion. The performance of the optimized portfolio relies on the accuracy of the estimated covariance matrix of the portfolio asset returns. For large portfolios, the number of available market returns is often of similar order to the number of assets, so that the sample covariance matrix performs poorly as a covariance estimator. Additionally, financial market data often contain outliers which, if not correctly handled, may further corrupt the covariance estimation. We address these shortcomings by studying the performance of a hybrid covariance matrix estimator based on Tyler's robust M-estimator and on Ledoit-Wolf's shrinkage estimator while assuming samples with heavy-tailed distribution. Employing recent results from random matrix theory, we develop a consistent estimator of (a scaled version of) the realized portfolio risk, which is minimized by optimizing online the shrinkage intensity. Our portfolio optimization method is shown via simulations to outperform existing methods both for synthetic and real market data.

Which factors are associated with global cognitive impairment in Wilson's disease?

PubMed Central

Frota, Norberto Anízio Ferreira; Barbosa, Egberto Reis; Porto, Claudia Sellitto; Lucato, Leandro Tavares; Ono, Carla Rachel; Buchpiguel, Carlos Alberto; Machado, Alexandre Aluizio Costa; Caramelli, Paulo

2016-01-01

Background Patients with Wilson's disease (WD) present cognitive impairment, especially in executive functions. Which other factors might be associated with global cognitive decline in these patients remains unclear. Objective To assess which factors are associated with worse performance on a global cognitive test in patients with WD. Methods Twenty patients with WD underwent cognitive assessment with the following tests: the Mini-Mental State Examination (MMSE), Dementia Rating Scale (DRS), verbal fluency test, brief cognitive battery, clock drawing test, Frontal Assessment Battery, Stroop test, Wisconsin card sorting test, Hopper test, cubes (WAIS) and the Pfeffer questionnaire. MRI changes were quantified. Patients with poor performance on the DRS were compared to patients with normal performance. Results Nine patients had a poor performance on the DRS. This group had lower educational level (9.11±3.58× 12.82±3.06) and a greater number of changes on MRI (9.44±2.74× 6.27±2.45). The presence of hyperintensity in the globus pallidus on MRI was more frequent in this group (66.6% vs 9.0%), with OR=5.38 (95% CI 0.85-33.86). Conclusion Global cognitive impairment was prevalent in this sample of patients with WD and was associated with low educational level, number of changes on MRI and MRI hyperintensity in the globus pallidus. PMID:29213476

Effect of bathing on atopic dermatitis during the summer season

PubMed Central

Kim, Hakyoung; Ban, Jeongsuk; Park, Mi-Ran; Kim, Do-Soo; Kim, Hye-Young; Han, Youngshin; Ahn, Kangmo

2012-01-01

Background There are little objective data regarding the optimal practice methods of bathing, although bathing and the use of moisturizers are the most important facets to atopic dermatitis (AD) management. Objective We performed this study to evaluate the effect of bathing on AD. Methods Ninety-six children with AD were enrolled during the summer season. Parents were educated to bathe them once daily with mildly acidic cleansers, and to apply emollients for 14 days. Parents recorded the frequency of bathing and skin symptoms in a diary. Scoring AD (SCORAD) scores were measured at the initial and follow-up visits. Patients were divided into two groups, based on the compliance of bathing; poor compliance was defined as ≥ 2 bathless days. Results There was an improvement of SCORAD score, itching, and insomnia in the good compliance group (all p < 0.001). The mean change in SCORAD score from the baseline at the follow-up visit was greater in the good compliance group than the poor compliance group (p = 0.038). Conclusion Daily bathing using weakly acidic syndets can reduce skin symptoms of pediatric AD during the summer season. PMID:23130333

Measurement error in earnings data: Using a mixture model approach to combine survey and register data.

PubMed

Meijer, Erik; Rohwedder, Susann; Wansbeek, Tom

2012-01-01

Survey data on earnings tend to contain measurement error. Administrative data are superior in principle, but they are worthless in case of a mismatch. We develop methods for prediction in mixture factor analysis models that combine both data sources to arrive at a single earnings figure. We apply the methods to a Swedish data set. Our results show that register earnings data perform poorly if there is a (small) probability of a mismatch. Survey earnings data are more reliable, despite their measurement error. Predictors that combine both and take conditional class probabilities into account outperform all other predictors.

Reducing failures of working memory with performance feedback.

PubMed

Adam, Kirsten C S; Vogel, Edward K

2016-10-01

Fluctuations in attentional control can lead to failures of working memory (WM), in which the subject is no better than chance at reporting items from a recent display. In three experiments, we used a whole-report measure of visual WM to examine the impact of feedback on the rate of failures. In each experiment, subjects remembered an array of colored items across a blank delay, and then reported the identity of items using a whole-report procedure. In Experiment 1, we gave subjects simple feedback about the number of items they correctly identified at the end of each trial. In Experiment 2, we gave subjects additional information about the cumulative number of items correctly identified within each block. Finally, in Experiment 3, we gave subjects weighted feedback in which poor trials resulted in lost points and consistent successful performance received "streak" points. Surprisingly, simple feedback (Exp. 1) was ineffective at improving average performance or decreasing the rate of poor-performance trials. Simple cumulative feedback (Exp. 2) modestly decreased poor-performance trials (by 7 %). Weighted feedback produced the greatest benefits, decreasing the frequency of poor-performance trials by 28 % relative to baseline performance. This set of results demonstrates the usefulness of whole-report WM measures for investigating the effects of feedback on WM performance. Further, we showed that only a feedback structure that specifically discouraged lapses using negative feedback led to large reductions in WM failures.

77 FR 9876 - Proposed Modification of VOR Federal Airways V-10, V-12, and V-508 in the Vicinity of Olathe, KS

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-21

... (OJC) VOR/DME navigation aid located on the Johnson County Executive Airport, Olathe, KS, due to poor performance of the navigation aid. The OJC VOR/DME performs poorly due to suburban encroachment into the...

12 CFR 367.6 - Causes for exclusion.

Code of Federal Regulations, 2010 CFR

2010-01-01

... default; or (2) The termination of such contract(s) for poor performance; or (3) A violation of the terms of a contract that would have resulted in a default or termination of the contract for poor... lack of integrity, or conspiracy to do the same; (l) The contractor's performance under previous...

Leadership Development: A Lever for System-Wide Educational Change

ERIC Educational Resources Information Center

Naicker, Suraiya R.; Mestry, Raj

2016-01-01

The continuous poor performance of South Africa's learners is detrimental to its developing economy. The need for education change prompted two universities to initiate a system-wide change strategy in a poorly performing school district. The leverage for change was leadership development, involving school principals and district officials. The…

Principals' Perceptions of Barriers to Dismissal of Poor-Performing Teachers

ERIC Educational Resources Information Center

Dandoy, Jason R.

2012-01-01

The purpose of this study is to determine which factors influence items that school principals consider "barriers" to dismissal of "incompetent" or "poor performing" teachers. This study determines if specific characteristics of schools, principals, or a combination of the two can predict the specific barriers cited…

Poorly Performing Physicians: Does the Script Concordance Test Detect Bad Clinical Reasoning?

ERIC Educational Resources Information Center

Goulet, Francois; Jacques, Andre; Gagnon, Robert; Charlin, Bernard; Shabah, Abdo

2010-01-01

Introduction: Evaluation of poorly performing physicians is a worldwide concern for licensing bodies. The College des Medecins du Quebec currently assesses the clinical competence of physicians previously identified with potential clinical competence difficulties through a day-long procedure called the Structured Oral Interview (SOI). Two peer…

Fine-scale patterns of population stratification confound rare variant association tests.

PubMed

O'Connor, Timothy D; Kiezun, Adam; Bamshad, Michael; Rich, Stephen S; Smith, Joshua D; Turner, Emily; Leal, Suzanne M; Akey, Joshua M

2013-01-01

Advances in next-generation sequencing technology have enabled systematic exploration of the contribution of rare variation to Mendelian and complex diseases. Although it is well known that population stratification can generate spurious associations with common alleles, its impact on rare variant association methods remains poorly understood. Here, we performed exhaustive coalescent simulations with demographic parameters calibrated from exome sequence data to evaluate the performance of nine rare variant association methods in the presence of fine-scale population structure. We find that all methods have an inflated spurious association rate for parameter values that are consistent with levels of differentiation typical of European populations. For example, at a nominal significance level of 5%, some test statistics have a spurious association rate as high as 40%. Finally, we empirically assess the impact of population stratification in a large data set of 4,298 European American exomes. Our results have important implications for the design, analysis, and interpretation of rare variant genome-wide association studies.

Planar heterojunction perovskite solar cells with superior reproducibility

PubMed Central

Jeon, Ye-Jin; Lee, Sehyun; Kang, Rira; Kim, Jueng-Eun; Yeo, Jun-Seok; Lee, Seung-Hoon; Kim, Seok-Soon; Yun, Jin-Mun; Kim, Dong-Yu

2014-01-01

Perovskite solar cells (PeSCs) have been considered one of the competitive next generation power sources. To date, light-to-electric conversion efficiencies have rapidly increased to over 10%, and further improvements are expected. However, the poor device reproducibility of PeSCs ascribed to their inhomogeneously covered film morphology has hindered their practical application. Here, we demonstrate high-performance PeSCs with superior reproducibility by introducing small amounts of N-cyclohexyl-2-pyrrolidone (CHP) as a morphology controller into N,N-dimethylformamide (DMF). As a result, highly homogeneous film morphology, similar to that achieved by vacuum-deposition methods, as well as a high PCE of 10% and an extremely small performance deviation within 0.14% were achieved. This study represents a method for realizing efficient and reproducible planar heterojunction (PHJ) PeSCs through morphology control, taking a major step forward in the low-cost and rapid production of PeSCs by solving one of the biggest problems of PHJ perovskite photovoltaic technology through a facile method. PMID:25377945

A novel approach to describing and detecting performance anti-patterns

NASA Astrophysics Data System (ADS)

Sheng, Jinfang; Wang, Yihan; Hu, Peipei; Wang, Bin

2017-08-01

Anti-pattern, as an extension to pattern, describes a widely used poor solution which can bring negative influence to application systems. Aiming at the shortcomings of the existing anti-pattern descriptions, an anti-pattern description method based on first order predicate is proposed. This method synthesizes anti-pattern forms and symptoms, which makes the description more accurate and has good scalability and versatility as well. In order to improve the accuracy of anti-pattern detection, a Bayesian classification method is applied in validation for detection results, which can reduce false negatives and false positives of anti-pattern detection. Finally, the proposed approach in this paper is applied to a small e-commerce system, the feasibility and effectiveness of the approach is demonstrated further through experiments.

Hyperfibrinogenemia is a poor prognostic factor in diffuse large B cell lymphoma.

PubMed

Niu, Jun-Ying; Tian, Tian; Zhu, Hua-Yuan; Liang, Jin-Hua; Wu, Wei; Cao, Lei; Lu, Rui-Nan; Wang, Li; Li, Jian-Yong; Xu, Wei

2018-06-02

Diffuse large B cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphomas worldwide. Previous studies indicated that hyperfibrinogenemia was a poor predictor in various tumors. The purpose of our study was to evaluate the prognostic effect of hyperfibrinogenemia in DLBCL. Data of 228 patients, who were diagnosed with DLBCL in our hospital between May 2009 and February 2016, were analyzed retrospectively. The Kaplan-Meier method and Cox regression were performed to find prognostic factors associated with progression-free survival (PFS) and overall survival (OS). Receiver operator characteristic (ROC) curve and the areas under the curve were used to evaluate the predictive accuracy of predictors. Comparison of characters between groups indicated that patients with high National Comprehensive Cancer Network-International Prognostic Index (NCCN-IPI) score (4-8) and advanced stage (III-IV) were more likely to suffer from hyperfibrinogenemia. The Kaplan-Meier method revealed that patients with hyperfibrinogenemia showed inferior PFS (P < 0.001) and OS (P < 0.001) than those without hyperfibrinogenemia. Multivariate analysis showed that hyperfibrinogenemia was an independent prognostic factor associated with poor outcomes (HR = 1.90, 95% CI: 1.15-3.16 for PFS, P = 0.013; HR = 2.65, 95% CI: 1.46-4.79 for OS, P = 0.001). We combined hyperfibrinogenemia and NCCN-IPI to build a new prognostic index (NPI). The NPI was demonstrated to have a superior predictive effect on prognosis (P = 0.0194 for PFS, P = 0.0034 for OS). Hyperfibrinogenemia was demonstrated to be able to predict poor outcome in DLBCL, especially for patients with advanced stage and high NCCN-IPI score. Adding hyperfibrinogenemia to NCCN-IPI could significantly improve the predictive effect of NCCN-IPI.

Development of Advanced Verification and Validation Procedures and Tools for the Certification of Learning Systems in Aerospace Applications

NASA Technical Reports Server (NTRS)

Jacklin, Stephen; Schumann, Johann; Gupta, Pramod; Richard, Michael; Guenther, Kurt; Soares, Fola

2005-01-01

Adaptive control technologies that incorporate learning algorithms have been proposed to enable automatic flight control and vehicle recovery, autonomous flight, and to maintain vehicle performance in the face of unknown, changing, or poorly defined operating environments. In order for adaptive control systems to be used in safety-critical aerospace applications, they must be proven to be highly safe and reliable. Rigorous methods for adaptive software verification and validation must be developed to ensure that control system software failures will not occur. Of central importance in this regard is the need to establish reliable methods that guarantee convergent learning, rapid convergence (learning) rate, and algorithm stability. This paper presents the major problems of adaptive control systems that use learning to improve performance. The paper then presents the major procedures and tools presently developed or currently being developed to enable the verification, validation, and ultimate certification of these adaptive control systems. These technologies include the application of automated program analysis methods, techniques to improve the learning process, analytical methods to verify stability, methods to automatically synthesize code, simulation and test methods, and tools to provide on-line software assurance.

Singing proficiency in the majority: normality and "phenotypes" of poor singing.

PubMed

Dalla Bella, Simone; Berkowska, Magdalena

2009-07-01

Recent evidence indicates that the majority of occasional singers can carry a tune. For example, when asked to sing a well-known song (e.g., "Happy Birthday"), nonmusicians performing at a slow tempo are as proficient as professional singers. Yet, some occasional singers are poor singers, mostly in the pitch domain, and sometimes despite not having impoverished perception. Poor singing is not a monolithic deficit, but is likely to be characterized by a diversity of singing "phenotypes." Here we systematically examined singing proficiency in a group of occasional singers, with the goal of characterizing the different patterns of poor singing. Participants sang three well-known melodies (e.g., "Jingle Bells") at a natural tempo and at a slow tempo, as indicated by a metronome. For each rendition, we computed objective measures of pitch and time accuracy with an acoustical method. The results confirmed previous observations that the majority of occasional singers can sing in tune and in time. Moreover, singing at a slow tempo after the target melody to be imitated was presented with a metronome improved pitch and time accuracy. In general, poor singers were mostly impaired on the pitch dimension, although various patterns of impairment emerged. Pitch accuracy or time accuracy could be selectively impaired; moreover, absolute measures of singing proficiency (pitch or tempo transposition) dissociated from relative measures of proficiency (pitch intervals, relative duration). These patterns of dissociations point to a multicomponent system underlying proficient singing that fractionates as a result of a developmental anomaly.

Examining asthma quality of care using a population-based approach

PubMed Central

Klomp, Helena; Lawson, Joshua A.; Cockcroft, Donald W.; Chan, Benjamin T.; Cascagnette, Paul; Gander, Laurie; Jorgenson, Derek

2008-01-01

Background Asthma accounts for considerable burden on health care, but in most cases, asthma can be controlled. Quality-of-care indicators would aid in monitoring asthma management. We describe the quality of asthma care using a set of proposed quality indicators. Methods We performed a retrospective cross-sectional study using health databases in Saskatchewan, a Canadian province with a population of about 1 million people. We assessed 6 quality-of-care indicators among people with asthma: admission to hospital because of asthma; poor asthma control (high use of short-acting β-agonists, admission to hospital because of asthma or death due to asthma); no inhaled corticosteroid use among patients with poor control; at least moderate inhaled corticosteroid use among patients with poor control; high inhaled corticosteroid use and use of another preventer medication among patients with poor control; and any main preventer use among patients with poor control. We calculated crude and adjusted rates with 95% confidence intervals. We tested for differences using the χ2 test for proportions and generalized linear modelling techniques. Results In 2002/03, there were 24 616 people aged 5–54 years with asthma in Saskatchewan, representing a prevalence of 3.8%. Poor symptom control was observed in 18% of patients with asthma. Among those with poor control, 37% were not dispensed any inhaled corticosteroids, and 40% received potentially inadequate doses. Among those with poor control who were dispensed high doses of inhaled corticosteroids, 26% also used another preventer medication. Hospital admissions because of asthma were highest among those aged 6–9 years and females aged 20–44 years. Males and those in adult age groups (predominantly 20–44 years) had worse quality of care for 4 indicators examined. Interpretation Suboptimal asthma management would be improved through increased use of inhaled corticosteroids and preventer medications, and reduced reliance on short-acting β-agonist medications as recommended by consensus guidelines. PMID:18390944

Black-white disparity in physical performance among older women with newly diagnosed non-metastatic breast cancer: Exploring the role of inflammation and physical activity.

PubMed

Owusu, Cynthia; Schluchter, Mark; Koroukian, Siran M; Schmitz, Kathryn H; Berger, Nathan A

2018-04-23

To examine racial differences in physical performance among older women with newly diagnosed non-metastatic breast cancer and identify clinical, behavioral and biological factors that might contribute to such disparities. This is a cross-sectional study of women aged ≥65 years with newly diagnosed stage I-III breast cancer recruited from ambulatory oncology clinics at an academic center, between September 2010 and August 2015. Participants completed a Comprehensive Geriatric Assessment and laboratory testing for biomarkers of inflammation [interleukin-6 (IL6)] prior to receiving systemic treatment for cancer. The primary outcome was poor physical performance, defined as scoring ≤7 on the Short Physical Performance Battery, Yes or No. Logistic regression analyses were undertaken. Among 135 women with mean age of 74.8 years (SD = 6.9), 31% were African-American (AA), and 33% had poor physical performance. Controlling for age, education, comorbidities and geriatric syndromes, participants with poor physical performance were more likely to be AA [versus (vs.) Non-Hispanic Whites (NHW)], odds ratio (OR) = 3.10, 95% confidence interval (CI) = 1.18-8.15. Controlling further for physical activity (PA) attenuated the racial disparity in physical performance (OR = 2.50, CI = 0.91-6.84). Lastly, controlling for IL6 further diminished the racial disparity in physical performance (OR = 1.93, CI = 0.67-5.56). In adjusted models, PA and IL6 explained 29% and 38%, respectively, of the racial disparity in poor physical performance. Among older women with newly diagnosed non-metastatic breast cancer, poor physical performance was prevalent and AA were disproportionately affected. Less engagement in physical activity and subclinical inflammation partly contributed to this disparity. Copyright © 2018 Elsevier Inc. All rights reserved.

Clinical utility of the Conners' Continuous Performance Test-II to detect poor effort in U.S. military personnel following traumatic brain injury.

PubMed

Lange, Rael T; Iverson, Grant L; Brickell, Tracey A; Staver, Tara; Pancholi, Sonal; Bhagwat, Aditya; French, Louis M

2013-06-01

The purpose of this study is to examine the clinical utility of the Conners' Continuous Performance Test (CPT-II) as an embedded marker of poor effort in military personnel undergoing neuropsychological evaluations following traumatic brain injury. Participants were 158 U.S. military service members divided into 3 groups on the basis of brain injury severity and performance (pass/fail) on 2 symptom validity tests: Mild Traumatic Brain Injury (MTBI)-Pass (n = 87), MTBI-Fail (n = 42), and severe traumatic brain injury (STBI)-Pass (n = 29). The MTBI-Fail group performed worse on the majority of CPT-II measures compared with both the MTBI-Pass and STBI-Pass groups. When comparing the MTBI-Fail group and MTBI-Pass groups, the most accurate measure for identifying poor effort was the Commission T score. When selected measures were combined (i.e., Omissions, Commissions, and Perseverations), there was a very small increase in sensitivity (from .26 to .29). When comparing the MTBI-Fail group and STBI-Pass groups, the most accurate measure for identifying poor effort was the Omission and Commissions T score. When selected measures were combined, sensitivity again increased (from .24 to .45). Overall, these results suggest that individual CPT-II measures can be useful for identifying people who are suspected of providing poor effort from those who have provided adequate effort. However, due to low sensitivity and modest negative predictive power values, this measure cannot be used in isolation to detect poor effort, and is largely useful as a test to "rule in," not "rule out" poor effort. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Adrenoleukodystrophy

MedlinePlus

... 10. The most common symptoms are usually behavioral changes such as abnormal withdrawal or aggression, poor memory, and poor school performance. Other symptoms include visual loss, learning disabilities, ...

A Methodological Critique of the ProPublica Surgeon Scorecard

PubMed Central

Friedberg, Mark W.; Pronovost, Peter J.; Shahian, David M.; Safran, Dana Gelb; Bilimoria, Karl Y.; Elliott, Marc N.; Damberg, Cheryl L.; Dimick, Justin B.; Zaslavsky, Alan M.

2016-01-01

Abstract On July 14, 2015, ProPublica published its Surgeon Scorecard, which displays “Adjusted Complication Rates” for individual, named surgeons for eight surgical procedures performed in hospitals. Public reports of provider performance have the potential to improve the quality of health care that patients receive. A valid performance report can drive quality improvement and usefully inform patients' choices of providers. However, performance reports with poor validity and reliability are potentially damaging to all involved. This article critiques the methods underlying the Scorecard and identifies opportunities for improvement. Until these opportunities are addressed, the authors advise users of the Scorecard—most notably, patients who might be choosing their surgeons—not to consider the Scorecard a valid or reliable predictor of the health outcomes any individual surgeon is likely to provide. The authors hope that this methodological critique will contribute to the development of more-valid and more-reliable performance reports in the future. PMID:28083411

49 CFR 240.309 - Railroad oversight responsibilities.

Code of Federal Regulations, 2010 CFR

2010-10-01

... reported train accidents attributed to poor safety performance by locomotive engineers; (3) The number and... and analysis concerning the administration of its program for responding to detected instances of poor... analysis shall involve: (1) The number and nature of the instances of detected poor safety conduct...

Analytical review based on statistics on good and poor financial performance of LPD in Bangli regency.

NASA Astrophysics Data System (ADS)

Yasa, I. B. A.; Parnata, I. K.; Susilawati, N. L. N. A. S.

2018-01-01

This study aims to apply analytical review model to analyze the influence of GCG, accounting conservatism, financial distress models and company size on good and poor financial performance of LPD in Bangli Regency. Ordinal regression analysis is used to perform analytical review, so that obtained the influence and relationship between variables to be considered further audit. Respondents in this study were LPDs in Bangli Regency, which amounted to 159 LPDs of that number 100 LPDs were determined as randomly selected samples. The test results found GCG and company size have a significant effect on both the good and poor financial performance, while the conservatism and financial distress model has no significant effect. The influence of the four variables on the overall financial performance of 58.8%, while the remaining 41.2% influenced by other variables. Size, FDM and accounting conservatism are variables, which are further recommended to be audited.

Utilization of alternative fuels in diesel engines

NASA Technical Reports Server (NTRS)

Lestz, S. A.

1984-01-01

Performance and emission data are collected for various candidate alternate fuels and compare these data to that for a certified petroleum based number two Diesel fuel oil. Results for methanol, ethanol, four vegetable oils, two shale derived oils, and two coal derived oils are reported. Alcohol fumigation does not appear to be a practical method for utilizing low combustion quality fuels in a Diesel engine. Alcohol fumigation enhances the bioactivity of the emitted exhaust particles. While it is possible to inject many synthetic fuels using the engine stock injection system, wholly acceptable performance is only obtained from a fuel whose specifications closely approach those of a finished petroleum based Diesel oil. This is illustrated by the contrast between the poor performance of the unupgraded coal derived fuel blends and the very good performance of the fully refined shale derived fuel.

Post processing of protein-compound docking for fragment-based drug discovery (FBDD): in-silico structure-based drug screening and ligand-binding pose prediction.

PubMed

Fukunishi, Yoshifumi

2010-01-01

For fragment-based drug development, both hit (active) compound prediction and docking-pose (protein-ligand complex structure) prediction of the hit compound are important, since chemical modification (fragment linking, fragment evolution) subsequent to the hit discovery must be performed based on the protein-ligand complex structure. However, the naïve protein-compound docking calculation shows poor accuracy in terms of docking-pose prediction. Thus, post-processing of the protein-compound docking is necessary. Recently, several methods for the post-processing of protein-compound docking have been proposed. In FBDD, the compounds are smaller than those for conventional drug screening. This makes it difficult to perform the protein-compound docking calculation. A method to avoid this problem has been reported. Protein-ligand binding free energy estimation is useful to reduce the procedures involved in the chemical modification of the hit fragment. Several prediction methods have been proposed for high-accuracy estimation of protein-ligand binding free energy. This paper summarizes the various computational methods proposed for docking-pose prediction and their usefulness in FBDD.

Humidification performance of 48 passive airway humidifiers: comparison with manufacturer data.

PubMed

Lellouche, François; Taillé, Solenne; Lefrançois, Frédéric; Deye, Nicolas; Maggiore, Salvatore Maurizio; Jouvet, Philippe; Ricard, Jean-Damien; Fumagalli, Bruno; Brochard, Laurent

2009-02-01

Heat and moisture exchangers (HMEs) are increasingly used in the ICU for gas conditioning during mechanical ventilation. Independent assessments of the humidification performance of HMEs are scarce. The aim of the present study was thus to assess the humidification performance of a large number of adult HMEs. We assessed 48 devices using a bench test apparatus that simulated real-life physiologic ventilation conditions. Thirty-two devices were described by the manufacturers as HMEs, and 16 were described as antibacterial filters. The test apparatus provided expiratory gases with an absolute humidity (AH) of 35 mg H(2)O/L. The AH of inspired gases was measured after steady state using the psychrometric method. We performed three hygrometric measurements for each device, measured their resistance, and compared our results with the manufacturer data. Of the 32 HMEs tested, only 37.5% performed well (>or= 30 mg H(2)O/L), while 25% performed poorly (< 25 mg H(2)O/L). The mean difference (+/- SD) between our measurements and the manufacturer data was 3.0 +/- 2.7 mg H(2)O/L for devices described as HMEs (maximum, 8.9 mg H(2)O/L) [p = 0.0001], while the mean difference for 36% of the HMEs was > 4 mg H(2)O/L. The mean difference for the antibacterial filters was 0.2 +/- 1.4 mg H(2)O/L. The mean resistance of all the tested devices was 2.17 +/- 0.70 cm H(2)O/L/s. Several HMEs performed poorly and should not be used as HMEs. The values determined by independent assessments may be lower than the manufacturer data. Describing a device as an HME does not guarantee that it provides adequate humidification. The performance of HMEs must be verified by independent assessment.

Oral and Written Expression in Children With Reading Comprehension Difficulties.

PubMed

Carretti, Barbara; Motta, Eleonora; Re, Anna Maria

2016-01-01

Several studies have highlighted that children with reading comprehension difficulties also have problems in tasks that involve telling a story, in writing or verbally. The main differences identified regard poor comprehenders' lower level of coherence in their productions by comparison with good comprehenders. Only one study has compared poor and good comprehenders' performance in both modalities (oral and written), however, to see whether these modalities differently influence poor comprehenders' performance. We qualitatively and quantitatively compared the performance of good and poor comprehenders in oral and written narrative tasks with the aim of shedding light on this issue. Regression analyses were also used to explore the role of working memory and vocabulary in explaining individual differences. Our results showed that the two groups produced narratives of comparable length, with similar percentages of spelling mistakes, whereas they differed in terms of the quality of their narratives, regardless of the modality. These differences were qualified by analyzing the children's use of connective devices, and poor comprehenders were found to use a higher proportion of additive devices than good comprehenders. Regression analyses showed that working memory (particularly the intrusion errors measure) explained a modest part of the qualitative differences in narrative production. Implications for our theoretical understanding of poor comprehenders' profiles and education are discussed. © Hammill Institute on Disabilities 2014.

Performance-based self-esteem and burnout in a cross-sectional study of medical students.

PubMed

Dahlin, M; Joneborg, N; Runeson, B

2007-02-01

To examine levels of burnout among medical students and test the hypothesis that high performance-based self-esteem is associated with burnout. Further to study associations between burnout and self-rated health. Cross-sectional survey, of medical students at 1st, 3rd and 6th year of medical school, N = 342, 59.1% women. Burnout was monitored by the Oldenburg Burnout Inventory (OLBI), comprising Exhaustion and Disengagement dimensions. Performance-based self-esteem (PBSE) was assessed by the PBSE-scale (PBSS) and self-rated health by SRH-5. The response rate was 90.4%. Females were more exhausted than males and sixth year students were most disengaged. High performance-based self-esteem was present in 41.7% of the respondents and poor health in 10.7%. Performance-based self-esteem had significant and moderate correlations with both burnout dimensions. Logistic regression showed a positive association between poor health and Exhaustion. Exhaustion among medical students was significantly associated with poor health, and deserves attention from teachers. Performance-based self-esteem was higher than in other populations and associated with both burnout dimensions, but not with poor health. Further research on study environment and burnout is needed, and the reasons for female students' higher exhaustion levels should be further investigated.

Arbitrary and semantic associations in subjective memory impairment and amnestic mild cognitive impairment among Taiwanese individuals: A cross-sectional study.

PubMed

Chang, Hsin-Te; Chen, Ta-Fu; Cheng, Ting-Wen; Lai, Ya-Mei; Hua, Mau-Sun

2018-05-01

Researchers have recently proposed a preclinical stage of dementia of Alzheimer's type (DAT), referred to as subjective memory impairment (SMI), with the aim of developing methods for the early detection of DAT and subsequent intervention. It has been proposed that the objective memory functions of individuals with SMI are normal; however, arbitrary and semantic associations are both used to describe the processes of memory. No previous studies have investigated these processes among individuals with SMI. Cross-sectional analysis was used to compare the memory function of individuals with SMI, amnestic mild cognitive impairment (aMCI), or DAT. One hundred and eighty-three participants were recruited from the Memory Clinic of National Taiwan University Hospital and communities in northern Taiwan, including individuals with no memory complaints (HC, n = 30) and individuals with SMI (n = 61), aMCI-single domain (n = 24), aMCI-multiple domain (n = 33), or DAT (n = 35). The Word Sequence Learning Test (WSLT) was used to assess the formation of arbitrary associations and the Logical Memory subtest of the Wechsler Memory Scale-Third Edition was used to assess the formation of semantic associations. Compared to the HC group, the SMI group performed poorly only on the WSLT, whereas the other groups performed poorly on both of the memory tasks. This study demonstrated that SMI individuals tend to perform poorly in the formation of arbitrary associations. Our findings suggest that tasks requiring arbitrary associations may provide greater sensitivity in the detection cognitive changes associated with preclinical DAT. Copyright © 2017. Published by Elsevier B.V.

Effect of Dopamine Therapy on Nonverbal Affect Burst Recognition in Parkinson's Disease

PubMed Central

Péron, Julie; Grandjean, Didier; Drapier, Sophie; Vérin, Marc

2014-01-01

Background Parkinson's disease (PD) provides a model for investigating the involvement of the basal ganglia and mesolimbic dopaminergic system in the recognition of emotions from voices (i.e., emotional prosody). Although previous studies of emotional prosody recognition in PD have reported evidence of impairment, none of them compared PD patients at different stages of the disease, or ON and OFF dopamine replacement therapy, making it difficult to determine whether their impairment was due to general cognitive deterioration or to a more specific dopaminergic deficit. Methods We explored the involvement of the dopaminergic pathways in the recognition of nonverbal affect bursts (onomatopoeias) in 15 newly diagnosed PD patients in the early stages of the disease, 15 PD patients in the advanced stages of the disease and 15 healthy controls. The early PD group was studied in two conditions: ON and OFF dopaminergic therapy. Results Results showed that the early PD patients performed more poorly in the ON condition than in the OFF one, for overall emotion recognition, as well as for the recognition of anger, disgust and fear. Additionally, for anger, the early PD ON patients performed more poorly than controls. For overall emotion recognition, both advanced PD patients and early PD ON patients performed more poorly than controls. Analysis of continuous ratings on target and nontarget visual analog scales confirmed these patterns of results, showing a systematic emotional bias in both the advanced PD and early PD ON (but not OFF) patients compared with controls. Conclusions These results i) confirm the involvement of the dopaminergic pathways and basal ganglia in emotional prosody recognition, and ii) suggest a possibly deleterious effect of dopatherapy on affective abilities in the early stages of PD. PMID:24651759

Crisis management can leave residual effects.

PubMed

Margolis, G L; DeMuro, P R

1991-10-01

A healthcare organization that once suffered from poor financial performance may fail to correct recovery methods that can cause lingering legal and accounting problems. A crisis management style is prone to creating problems with an organization's debt structure, Medicare and Medicaid payment, tax issues, labor relations, licensing and accreditation, compliance with fraud and abuse rules, and accounting for charity care. After stabilizing a worrisome financial situation, a healthcare organization should conduct an internal audit to ensure that its legal and accounting practices remain above board.

Promoting Airmen with the Potential to Lead: A Study of the Air Force Master Sergeant Promotion System

DTIC Science & Technology

2014-01-01

than men. A common rule of thumb for measuring the existence of adverse impact is the four-fifths rule, which says that adverse impact is...a test. Similarly, another respondent commented that the current system “ says if you hang in there long enough, then you can get promoted, and I...Consequently, we did not review assessment methods found to be poor predictors of performance (e.g., handwriting analysis known as graphology

Deployment Simulation Methods for Ultra-Lightweight Inflatable Structures

NASA Technical Reports Server (NTRS)

Wang, John T.; Johnson, Arthur R.

2003-01-01

Two dynamic inflation simulation methods are employed for modeling the deployment of folded thin-membrane tubes. The simulations are necessary because ground tests include gravity effects and may poorly represent deployment in space. The two simulation methods are referred to as the Control Volume (CV) method and the Arbitrary Lagrangian Eulerian (ALE) method. They are available in the LS-DYNA nonlinear dynamic finite element code. Both methods are suitable for modeling the interactions between the inflation gas and the thin-membrane tube structures. The CV method only considers the pressure induced by the inflation gas in the simulation, while the ALE method models the actual flow of the inflation gas. Thus, the transient fluid properties at any location within the tube can be predicted by the ALE method. Deployment simulations of three packaged tube models; namely coiled, Z-folded, and telescopically-folded configurations, are performed. Results predicted by both methods for the telescopically-folded configuration are correlated and computational efficiency issues are discussed.

Understanding Preclerkship Medical Students' Poor Performance in Prescription Writing.

PubMed

James, Henry; Al Khaja, Khalid A J; Tayem, Yasin I; Veeramuthu, Sindhan; Sequeira, Reginald P

2016-05-01

This study aimed to explore reasons for poor performance in prescription writing stations of the objective structured practical examination (OSPE) and absenteeism in prescription writing sessions among preclerkship medical students at the Arabian Gulf University (AGU) in Manama, Bahrain. This descriptive study was carried out between September 2014 and June 2015 among 157 preclerkship medical students at AGU. Data were collected using focus group discussions and a questionnaire with closed- and open-ended items. All 157 students participated in the study (response rate: 100.0%). The most frequently cited reasons for poor performance in OSPE stations were an inability to select the correct drugs (79.6%), treatment duration (69.4%), drug quantity (69.4%) and drug formulation (68.2%). Additionally, students reported inadequate time for completing the stations (68.8%). During focus group discussions, students reported other reasons for poor performance, including examination stress and the difficulty of the stations. Absenteeism was attributed to the length of each session (55.4%), lack of interest (50.3%), reliance on peers for information (48.4%) and optional attendance policies (47.1%). Repetitive material, large group sessions, unmet student expectations and the proximity of the sessions to summative examinations were also indicated to contribute to absenteeism according to open-ended responses or focus group discussions. This study suggests that AGU medical students perform poorly in prescription writing OSPE stations because of inadequate clinical pharmacology knowledge. Participation in prescription writing sessions needs to be enhanced by addressing the concerns identified in this study. Strategies to improve attendance and performance should take into account the learner-teacher relationship.

The association of snoring and risk of obstructive sleep apnea with poor academic performance among university students.

PubMed

Khassawneh, Basheer Y; Alkhatib, Loiy L; Ibnian, Ali M; Khader, Yousef S

2018-04-20

Subjects with obstructive sleep apnea (OSA) have neurocognitive dysfunction. The aim of this study was to estimate the prevalence of symptoms and risk of OSA among university students and the association with academic performance. A cross-sectional study was conducted at Jordan University of Science and Technology. Students from faculties of engineering, medicine, nursing, pharmacy, and dentistry were asked to participate in this study. The Berlin Sleep Questionnaire was used to report symptoms and risk of OSA. Below average cumulative scores were considered poor academic performance. A total of 777 students (51% female; mean age, 20 years) completed the study questionnaire. According to the study definition, 42 students (5.4%) had high risk for OSA. Snoring was reported by 11% and daytime sleepiness and fatigue by 30%. Compared to female students, male students had more snoring (14.6 vs. 7.6%, p = 0.002) and higher risk for OSA (6.5 vs. 1.6%, p = 0.001). Both self-reported snoring and being at high risk for OSA were associated with poor academic performance (27.9 vs. 11.6% and 23.1 vs. 9.2%, respectively; p < 0.02). After adjusting for confounding factors, the odds ratio of having poor academic performance in students at high risk for OSA was 2.4 (CI 1.11-5.2, p = 0.027). Snoring and OSA were uncommon among university students. However, both were more common among male students and were associated with poor academic performance.

Oral health and impact on performance of athletes participating in the London 2012 Olympic Games: a cross-sectional study

PubMed Central

Needleman, I; Ashley, P; Petrie, A; Fortune, F; Turner, W; Jones, J; Niggli, J; Engebretsen, L; Budgett, R; Donos, N; Clough, T; Porter, S

2013-01-01

Background Oral health is important both for well-being and successful elite sporting performance. Reports from Olympic Games have found significant treatment needs; however, few studies have examined oral health directly. The aim of this study was to evaluate oral health, the determinants of oral health and the effect of oral health on well-being, training and performance of athletes participating in the London 2012 Games. Methods Cross-sectional study at the dental clinic within the Polyclinic in the athletes’ village. Following informed consent, a standardised history, clinical examination and brief questionnaire were conducted. Results 302 athletes from 25 sports were recruited with data available for 278. The majority of athletes were from Africa, the Americas and Europe. Overall, the results demonstrated high levels of poor oral health including dental caries (55% athletes), dental erosion (45% athletes) and periodontal disease (gingivitis 76% athletes, periodontitis 15% athletes). More than 40% of athletes were ‘bothered’ by their oral health with 28% reporting an impact on quality of life and 18% on training and performance. Nearly half of the participants had not undergone a dental examination or hygiene care in the previous year. Conclusions The oral health of athletes attending the dental clinic of the London 2012 Games was poor with a resulting substantial negative impact on well-being, training and performance. As oral health is an important element of overall health and well-being, health promotion and disease prevention interventions are urgently required to optimise athletic performance. PMID:24068332

The Chemistry Development Kit (CDK) v2.0: atom typing, depiction, molecular formulas, and substructure searching.

PubMed

Willighagen, Egon L; Mayfield, John W; Alvarsson, Jonathan; Berg, Arvid; Carlsson, Lars; Jeliazkova, Nina; Kuhn, Stefan; Pluskal, Tomáš; Rojas-Chertó, Miquel; Spjuth, Ola; Torrance, Gilleain; Evelo, Chris T; Guha, Rajarshi; Steinbeck, Christoph

2017-06-06

The Chemistry Development Kit (CDK) is a widely used open source cheminformatics toolkit, providing data structures to represent chemical concepts along with methods to manipulate such structures and perform computations on them. The library implements a wide variety of cheminformatics algorithms ranging from chemical structure canonicalization to molecular descriptor calculations and pharmacophore perception. It is used in drug discovery, metabolomics, and toxicology. Over the last 10 years, the code base has grown significantly, however, resulting in many complex interdependencies among components and poor performance of many algorithms. We report improvements to the CDK v2.0 since the v1.2 release series, specifically addressing the increased functional complexity and poor performance. We first summarize the addition of new functionality, such atom typing and molecular formula handling, and improvement to existing functionality that has led to significantly better performance for substructure searching, molecular fingerprints, and rendering of molecules. Second, we outline how the CDK has evolved with respect to quality control and the approaches we have adopted to ensure stability, including a code review mechanism. This paper highlights our continued efforts to provide a community driven, open source cheminformatics library, and shows that such collaborative projects can thrive over extended periods of time, resulting in a high-quality and performant library. By taking advantage of community support and contributions, we show that an open source cheminformatics project can act as a peer reviewed publishing platform for scientific computing software. Graphical abstract CDK 2.0 provides new features and improved performance.

Selecting between-sample RNA-Seq normalization methods from the perspective of their assumptions.

PubMed

Evans, Ciaran; Hardin, Johanna; Stoebel, Daniel M

2017-02-27

RNA-Seq is a widely used method for studying the behavior of genes under different biological conditions. An essential step in an RNA-Seq study is normalization, in which raw data are adjusted to account for factors that prevent direct comparison of expression measures. Errors in normalization can have a significant impact on downstream analysis, such as inflated false positives in differential expression analysis. An underemphasized feature of normalization is the assumptions on which the methods rely and how the validity of these assumptions can have a substantial impact on the performance of the methods. In this article, we explain how assumptions provide the link between raw RNA-Seq read counts and meaningful measures of gene expression. We examine normalization methods from the perspective of their assumptions, as an understanding of methodological assumptions is necessary for choosing methods appropriate for the data at hand. Furthermore, we discuss why normalization methods perform poorly when their assumptions are violated and how this causes problems in subsequent analysis. To analyze a biological experiment, researchers must select a normalization method with assumptions that are met and that produces a meaningful measure of expression for the given experiment. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The Influence of Closing Poor Performing Primary Schools on the Educational Attainment of Students

ERIC Educational Resources Information Center

De Witte, Kristof; Van Klaveren, Chris

2014-01-01

This paper examines whether the closure of poor performing primary schools improved students' educational attainment. It is believed that school closure affects children's educational outcomes positively because children switch to better primary schools. At the same time, school closure creates a social disturbance such that educational outcomes…

Experiences of Second-Class Citizenship Related to Continued Poor Academic Performance of Minority Xhosa Learners

ERIC Educational Resources Information Center

Dreyer, Lorna M.; Singh, Suzanne A. M.

2016-01-01

This article examines the subjective life experiences of racial minority Xhosa speakers and the factors that contribute to their continued poor academic performance in a previously Whites-only school in South Africa. Vygotskian sociocultural perspective in relation to creating a democratic educational system and Bronfenbrenner's biosystemic theory…

Faculty Response to Department Leadership: Strategies for Creating More Supportive Academic Work Environments

ERIC Educational Resources Information Center

Miller, Michael T.; Murry, John W., Jr.

2015-01-01

Having a strong, positive departmental chair is critical to enhancing and assuring faculty performance and student learning. Poor leadership, however, can result in increased faculty turn over, poor teaching and research performance, and even the discouragement of students from enrolling. The current study explored response strategies by faculty…

Instructor Responses to Poor Student Communication Performance: An Attributional Interpretation.

ERIC Educational Resources Information Center

Fiechtner, Susan Brown; Krayer, Karl J.

A study was conducted (1) to investigate factors that influence an instructor's choice of behavior when confronted with incidents of students' poor communication performance, and (2) to demonstrate how attribution theory can be used as a vehicle for describing and understanding the causes of instructor reactions or behaviors. The study sought to…

Enhanced encapsulation and bioavailability of breviscapine in PLGA microparticles by nanocrystal and water-soluble polymer template techniques.

PubMed

Wang, Hong; Zhang, Guangxing; Ma, Xueqin; Liu, Yanhua; Feng, Jun; Park, Kinam; Wang, Wenping

2017-06-01

Poly (lactide-co-glycolide) (PLGA) microparticles are widely used for controlled drug delivery. Emulsion methods have been commonly used for preparation of PLGA microparticles, but they usually result in low loading capacity, especially for drugs with poor solubility in organic solvents. In the present study, the nanocrystal technology and a water-soluble polymer template method were used to fabricate nanocrystal-loaded microparticles with improved drug loading and encapsulation efficiency for prolonged delivery of breviscapine. Breviscapine nanocrystals were prepared using a precipitation-ultrasonication method and further loaded into PLGA microparticles by casting in a mold from a water-soluble polymer. The obtained disc-like particles were then characterized and compared with the spherical particles prepared by an emulsion-solvent evaporation method. X-ray powder diffraction (XRPD) and confocal laser scanning microscopy (CLSM) analysis confirmed a highly-dispersed state of breviscapine inside the microparticles. The drug form, loading percentage and fabrication techniques significantly affected the loading capacity and efficiency of breviscapine in PLGA microparticles, and their release performance as well. Drug loading was increased from 2.4% up to 15.3% when both nanocrystal and template methods were applied, and encapsulation efficiency increased from 48.5% to 91.9%. But loading efficiency was reduced as the drug loading was increased. All microparticles showed an initial burst release, and then a slow release period of 28days followed by an erosion-accelerated release phase, which provides a sustained delivery of breviscapine over a month. A relatively stable serum drug level for more than 30days was observed after intramuscular injection of microparticles in rats. Therefore, PLGA microparticles loaded with nanocrystals of poorly soluble drugs provided a promising approach for long-term therapeutic products characterized with preferable in vitro and in vivo performance. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of two- and three-dimensional assessment methods of nasolabial appearance in cleft lip and palate patients: Do the assessment methods measure the same outcome?

PubMed

Mosmuller, David G M; Maal, Thomas J; Prahl, Charlotte; Tan, Robin A; Mulder, Frans J; Schwirtz, Roderic M F; de Vet, Henrica C W; Bergé, Stefaan J; Don Griot, J P W

2017-08-01

For the assessment of the nasolabial appearance in cleft patients, a widely accepted, reliable scoring system is not available. In this study four different methods of assessment are compared, including 2D and 3D asymmetry and aesthetic assessments. The data and ratings from an earlier study using the Asher-McDade aesthetic index on 3D photographs and the outcomes of 3D facial distance mapping were compared to a 2D aesthetic assessment, the Cleft Aesthetic Rating Scale, and to SymNose, a computerized 2D asymmetry assessment technique. The reliability and correlation between the four assessment techniques were tested using a sample of 79 patients. The 3D asymmetry assessment had the highest reliability and could be performed by just one observer (Intraclass correlation coefficient (ICC): 0.99). The 2D asymmetry assessment of the nose was highly reliable when performed by just one observer (ICC: 0.89). However, for the 2D asymmetry assessment of the lip more observers were needed. For the 2D aesthetic assessments 3 observers were needed. The 3D aesthetic assessment had the lowest single-observer reliability (ICC: 0.38-0.56) of all four techniques. The agreement between the different assessment methods is poor to very poor. The highest correlation (R: 0.48) was found between 2D and 3D aesthetic assessments. Remarkably, the lowest correlations were found between 2D and 3D asymmetry assessments (0.08-0.17). Different assessment methods are not in agreement and seem to measure different nasolabial aspects. More research is needed to establish exactly what each assessment technique measures and which measurements or outcomes are relevant for the patients. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Detecting representative data and generating synthetic samples to improve learning accuracy with imbalanced data sets.

PubMed

Li, Der-Chiang; Hu, Susan C; Lin, Liang-Sian; Yeh, Chun-Wu

2017-01-01

It is difficult for learning models to achieve high classification performances with imbalanced data sets, because with imbalanced data sets, when one of the classes is much larger than the others, most machine learning and data mining classifiers are overly influenced by the larger classes and ignore the smaller ones. As a result, the classification algorithms often have poor learning performances due to slow convergence in the smaller classes. To balance such data sets, this paper presents a strategy that involves reducing the sizes of the majority data and generating synthetic samples for the minority data. In the reducing operation, we use the box-and-whisker plot approach to exclude outliers and the Mega-Trend-Diffusion method to find representative data from the majority data. To generate the synthetic samples, we propose a counterintuitive hypothesis to find the distributed shape of the minority data, and then produce samples according to this distribution. Four real datasets were used to examine the performance of the proposed approach. We used paired t-tests to compare the Accuracy, G-mean, and F-measure scores of the proposed data pre-processing (PPDP) method merging in the D3C method (PPDP+D3C) with those of the one-sided selection (OSS), the well-known SMOTEBoost (SB) study, and the normal distribution-based oversampling (NDO) approach, and the proposed data pre-processing (PPDP) method. The results indicate that the classification performance of the proposed approach is better than that of above-mentioned methods.

Prediction of brain-computer interface aptitude from individual brain structure.

PubMed

Halder, S; Varkuti, B; Bogdan, M; Kübler, A; Rosenstiel, W; Sitaram, R; Birbaumer, N

2013-01-01

Brain-computer interface (BCI) provide a non-muscular communication channel for patients with impairments of the motor system. A significant number of BCI users is unable to obtain voluntary control of a BCI-system in proper time. This makes methods that can be used to determine the aptitude of a user necessary. We hypothesized that integrity and connectivity of involved white matter connections may serve as a predictor of individual BCI-performance. Therefore, we analyzed structural data from anatomical scans and DTI of motor imagery BCI-users differentiated into high and low BCI-aptitude groups based on their overall performance. Using a machine learning classification method we identified discriminating structural brain trait features and correlated the best features with a continuous measure of individual BCI-performance. Prediction of the aptitude group of each participant was possible with near perfect accuracy (one error). Tissue volumetric analysis yielded only poor classification results. In contrast, the structural integrity and myelination quality of deep white matter structures such as the Corpus Callosum, Cingulum, and Superior Fronto-Occipital Fascicle were positively correlated with individual BCI-performance. This confirms that structural brain traits contribute to individual performance in BCI use.

Land Cover Classification in a Complex Urban-Rural Landscape with Quickbird Imagery

PubMed Central

Moran, Emilio Federico.

2010-01-01

High spatial resolution images have been increasingly used for urban land use/cover classification, but the high spectral variation within the same land cover, the spectral confusion among different land covers, and the shadow problem often lead to poor classification performance based on the traditional per-pixel spectral-based classification methods. This paper explores approaches to improve urban land cover classification with Quickbird imagery. Traditional per-pixel spectral-based supervised classification, incorporation of textural images and multispectral images, spectral-spatial classifier, and segmentation-based classification are examined in a relatively new developing urban landscape, Lucas do Rio Verde in Mato Grosso State, Brazil. This research shows that use of spatial information during the image classification procedure, either through the integrated use of textural and spectral images or through the use of segmentation-based classification method, can significantly improve land cover classification performance. PMID:21643433

Nonlinear Characterization of Half and Full Wavelength Power Ultrasonic Devices

NASA Astrophysics Data System (ADS)

Mathieson, Andrew; Cerisola, Niccolò; Cardoni, Andrea

It is well known that power ultrasonic devices whilst driven under elevated excitation levels exhibit nonlinear behaviors. If no attempt is made to understand and subsequently control these behaviors, these devices can exhibit poor performance or even suffer premature failure. This paper presents an experimental method for the dynamic characterization of a commercial ultrasonic transducer for bone cutting applications (Piezosurgery® Device) operated together with a variety of rod horns that are tuned to operate in a longitudinal mode of vibration. Near resonance responses, excited via a burst sine sweep method were used to identify nonlinear responses exhibited by the devices, while experimental modal analysis was performed to identify the modal parameters of the longitudinal modes of vibration of the assemblies between 0-80 kHz. This study tries to provide an understanding of the effects that geometry and material choices may have on the nonlinear behavior of a tuned device.

A simple strategy to reduce stereotype threat for orthopedic residents.

PubMed

Gomez, Everlyne; Wright, James G

2014-04-01

Stereotype threat, defined as the predicament felt by people in either positive or negative learning experiences where they could conform to negative stereotypes associated with their own group membership, can interfere with learning. The purpose of this study was to determine if a simple orientation session could reduce stereotype threat for orthopedic residents. The intervention group received an orientation on 2 occasions focusing on their possible responses to perceived poor performance in teaching rounds and the operating room (OR). Participants completed a survey with 7 questions typical for stereotype threat evaluating responses to their experiences. The questions had 7 response options with a maximum total score of 49, where higher scores indicated greater degree of experiences typical of stereotype threat. Of the 84 eligible residents, 49 participated: 22 in the nonintervention and 27 in the intervention group. The overall scores were 29 and 29.4, and 26.2 and 25.8 in the nonintervention and intervention groups for their survey responses to perceived poor performance in teaching rounds (p = 0.85) and the OR (p = 0.84), respectively. Overall, responses typical of stereotype threat were greater for perceived poor performance at teaching rounds than in the OR (p = 0.001). Residents experience low self-esteem following perceived poor performance, particularly at rounds. A simple orientation designed to reduce stereotype threat was unsuccessful in reducing this threat overall. Future research will need to consider longer-term intervention as possible strategies to reduce perceived poor performance at teaching rounds and in the OR.

Synthesis of hierarchical porous δ-MnO2 nanoboxes as an efficient catalyst for rechargeable Li-O2 batteries

NASA Astrophysics Data System (ADS)

Zhang, Jian; Luan, Yanping; Lyu, Zhiyang; Wang, Liangjun; Xu, Leilei; Yuan, Kaidi; Pan, Feng; Lai, Min; Liu, Zhaolin; Chen, Wei

2015-09-01

A rechargeable lithium-oxygen (Li-O2) battery with a remarkably high theoretical energy storage capacity has attracted enormous research attention. However, the poor oxygen reduction and oxygen evolution reaction (ORR and OER) activities in discharge and charge processes cause low energy efficiency, poor electrolyte stability and short cycle life. This requires the development of efficient cathode catalysts to dramatically improve the Li-O2 battery performances. MnO2-based materials are recognized as efficient and low-cost catalysts for a Li-O2 battery cathode. Here, we report a controllable approach to synthesize hierarchical porous δ-MnO2 nanoboxes by using Prussian blue analogues as the precursors. The obtained products possess hierarchical pore size and an extremely large surface area (249.3 m2 g-1), which would favour oxygen transportation and provide more catalytically active sites to promote ORR and OER as the Li-O2 battery cathode. The battery shows enhanced discharge capacity (4368 mA h g-1@0.08 mA cm-2), reduced overpotential (270 mV), improved rate performance and excellent cycle stability (248 cycles@500 mA h g-1 and 112 cycles@1000 mA h g-1), in comparison with the battery with a VX-72 carbon cathode. The superb performance of the hierarchical porous δ-MnO2 nanoboxes, together with a convenient fabrication method, presents an alternative to develop advanced cathode catalysts for the Li-O2 battery.A rechargeable lithium-oxygen (Li-O2) battery with a remarkably high theoretical energy storage capacity has attracted enormous research attention. However, the poor oxygen reduction and oxygen evolution reaction (ORR and OER) activities in discharge and charge processes cause low energy efficiency, poor electrolyte stability and short cycle life. This requires the development of efficient cathode catalysts to dramatically improve the Li-O2 battery performances. MnO2-based materials are recognized as efficient and low-cost catalysts for a Li-O2 battery cathode. Here, we report a controllable approach to synthesize hierarchical porous δ-MnO2 nanoboxes by using Prussian blue analogues as the precursors. The obtained products possess hierarchical pore size and an extremely large surface area (249.3 m2 g-1), which would favour oxygen transportation and provide more catalytically active sites to promote ORR and OER as the Li-O2 battery cathode. The battery shows enhanced discharge capacity (4368 mA h g-1@0.08 mA cm-2), reduced overpotential (270 mV), improved rate performance and excellent cycle stability (248 cycles@500 mA h g-1 and 112 cycles@1000 mA h g-1), in comparison with the battery with a VX-72 carbon cathode. The superb performance of the hierarchical porous δ-MnO2 nanoboxes, together with a convenient fabrication method, presents an alternative to develop advanced cathode catalysts for the Li-O2 battery. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr02983j

Skin grafts: a rural general surgical perspective.

PubMed

Henderson, Nigel J; Fancourt, Michael; Gilkison, William; Kyle, Stephen; Mosquera, Damien

2009-05-01

Skin grafts are a common method of closing skin defects. The literature comparing methods of graft application and subsequent outcomes is poor, but reports indicate a graft failure rate between 2 and 30%. The aim of this study was to audit our current skin graft practice. Data were collected prospectively on all skin grafts performed by the general surgical department between 1st December 2005 and 1st December 2006. A standardized proforma on each patient included data on age, gender, graft indication, application method, comorbidities, length of stay, and graft outcomes including graft take at 1, 2 and 6 weeks post-operatively. There were 85 grafts performed on 74 patients, median age 72 years (9-102 years), with 10 (12%) acute admissions. Prophylactic antibiotics were given to 50% (38 of 74) of patients. Successful grafts (>80% take) were performed in 68 (80%) patients. The overall graft complication rate was 24.7% (22 of 85 grafts). Infection occurred in 13 of 17 graft failures. No patients underwent re-operation for graft failure. Patients who received prophylactic antibiotics had a reduced risk of graft failure (Fisher's exact test, P = 0.016). Skin grafts were performed successfully in the majority of patients. Graft complication and failure rates compare well with the world literature. The use of prophylactic antibiotics was the only predictor of successful graft take.

Self-rated imagery and encoding strategies in visual memory.

PubMed

Berger, G H; Gaunitz, S C

1979-02-01

The value of self-rated vividness of imagery in predicting performance was investigated, taking into account the mnemonic strategies utilized among subjects performing a visual-memory task. Subjects classified as 'good' or 'poor' imagers, according to their scores in the Vividness of Visual Imagery Questionnaire (VVIQ; Marks, 1972), were to detect as rapidly as possible differences between pairs of similar pictures presented consecutively. No coding instructions were given and the mnemonic strategies used were analysed by studying subjective reports and objective performance measurements. The results indicated that the subjects utilized two main strategies--a detail or an image strategy. The detail strategy was the more efficient. In accordance with a previous study (Berger & Gaunitz, 1977), it was found that the VVIQ did not discriminate between performance by 'good' and 'poor' imagers. However, among subjects who used the image strategy, 'good' imagers performed more rapidly than 'poor' imagers. Self-rated imagery may then have some value in predicting performance among individuals shown to have utilized an image strategy.

Selected physical and chemical properties of Feverfew (Tanacetum parthenium) extracts important for formulated product quality and performance.

PubMed

Jin, Ping; Madieh, Shadi; Augsburger, Larry L

2008-01-01

The objectives of this research are: (1) to assess selected formulation-relevant physical properties of several commercial Feverfew extracts, including flowability, hygroscopicity, compressibility and compactibility (2) to develop and validate a suitable extraction method and HPLC assay, and (3) to determine the parthenolide content of several commercial Feverfew extracts. Carr's index, minimum orifice diameter and particle-particle interaction were used to evaluate powder flowability. Hygroscopicity was evaluated by determining the equilibrium moisture content (EMC) after storage at various % relative humidities. Heckle analysis and compression pressure-radial tensile strength relationship were used to represent compression and compaction properties of feverfew extracts. An adapted analytical method was developed based on literature methods and then validated for the determination of parthenolide in feverfew. The commercial extracts tested exhibited poor to very poor flowability. The comparatively low mean yield pressure suggested that feverfew extracts deformed mainly plastically. Hygroscopicity and compactibility varied greatly with source. No commercial feverfew extracts tested contained the label claimed parthenolide. Even different batches from the same manufacturer showed significantly different parthenolide content. Therefore, extract manufactures should commit to proper quality control procedures that ensure accurate label claims, and supplement manufacturers should take into account possible differences in physico-chemical properties when using extracts from multiple suppliers.

Impact of hygiene of housing conditions on performance and health of two pig genetic lines divergent for residual feed intake.

PubMed

Chatelet, A; Gondret, F; Merlot, E; Gilbert, H; Friggens, N C; Le Floc'h, N

2018-02-01

Pigs selected for high performance may be more at risk of developing diseases. This study aimed to assess the health and performance of two pig lines divergently selected for residual feed intake (RFI) (low RFI (LRFI) v. high RFI (HRFI)) and housed in two contrasted hygiene conditions (poor v. good) using a 2×2 factorial design (n=40/group). The challenge period (Period 1), started on week zero (W0) when 12-week-old pigs were transferred to good or poor housing conditions. At week 6 (W6), half of the pigs in each group were slaughtered. During a recovery period (Period 2) from W6 to W13 to W14, the remaining pigs (n=20/group) were transferred in good hygiene conditions before being slaughtered. Blood was collected every three (Period 1) or 2 weeks (Period 2) to assess blood indicators of immune and inflammatory responses. Pulmonary lesions at slaughter and performance traits were evaluated. At W6, pneumonia prevalence was greater for pigs housed in poor than in good conditions (51% v. 8%, respectively, P<0.001). Irrespective of hygiene conditions, lung lesion scores were lower for LRFI pigs than for HRFI pigs (P=0.03). At W3, LRFI in poor conditions had the highest number of blood granulocytes (hygiene×line, P=0.03) and at W6, HRFI pigs in poor conditions had the greatest plasma haptoglobin concentrations (hygiene×line, P=0.02). During Period 1, growth rate and growth-to-feed ratio were less affected by poor hygiene in LRFI pigs than in HRFI pigs (hygiene×line, P=0.001 and P=0.02, respectively). Low residual feed intake pigs in poor conditions ate more than the other groups (hygiene×line, P=0.002). Irrespective of the line, fasting plasma glucose concentrations were higher in poor conditions, whereas fasting free fatty acids concentrations were lower than in good conditions. At the end of Period 2, pneumonia prevalence was similar for both housing conditions (39% v. 38%, respectively). During Period 2, plasma protein concentrations were greater for pigs previously housed in poor than in good conditions during Period 1. Immune traits, gain-to-feed ratio, BW gain and feed consumption did not differ during Period 2. Nevertheless, at W12, BW of HRFI previously housed in poor conditions was 13.4 kg lower than BW of HRFI pigs (P<0.001) previously housed in good conditions. In conclusion, health of the most feed efficient LRFI pigs was less impaired by poor hygiene conditions. This line was able to preserve its health, growth performance and its feed ingestion to a greater extent than the less efficient HRFI line.

A coupled hydrological-hydraulic flood inundation model calibrated using post-event measurements and integrated uncertainty analysis in a poorly gauged Mediterranean basin

NASA Astrophysics Data System (ADS)

Hdeib, Rouya; Abdallah, Chadi; Moussa, Roger; Colin, Francois

2017-04-01

Developing flood inundation maps of defined exceedance probabilities is required to provide information on the flood hazard and the associated risk. A methodology has been developed to model flood inundation in poorly gauged basins, where reliable information on the hydrological characteristics of floods are uncertain and partially captured by the traditional rain-gauge networks. Flood inundation is performed through coupling a hydrological rainfall-runoff (RR) model (HEC-HMS) with a hydraulic model (HEC-RAS). The RR model is calibrated against the January 2013 flood event in the Awali River basin, Lebanon (300 km2), whose flood peak discharge was estimated by post-event measurements. The resulting flows of the RR model are defined as boundary conditions of the hydraulic model, which is run to generate the corresponding water surface profiles and calibrated against 20 post-event surveyed cross sections after the January-2013 flood event. An uncertainty analysis is performed to assess the results of the models. Consequently, the coupled flood inundation model is simulated with design storms and flood inundation maps are generated of defined exceedance probabilities. The peak discharges estimated by the simulated RR model were in close agreement with the results from different empirical and statistical methods. This methodology can be extended to other poorly gauged basins facing common stage-gauge failure or characterized by floods with a stage exceeding the gauge measurement level, or higher than that defined by the rating curve.

Poor quality vital anti-malarials in Africa - an urgent neglected public health priority

PubMed Central

2011-01-01

Background Plasmodium falciparum malaria remains a major public health problem. A vital component of malaria control rests on the availability of good quality artemisinin-derivative based combination therapy (ACT) at the correct dose. However, there are increasing reports of poor quality anti-malarials in Africa. Methods Seven collections of artemisinin derivative monotherapies, ACT and halofantrine anti-malarials of suspicious quality were collected in 2002/10 in eleven African countries and in Asia en route to Africa. Packaging, chemical composition (high performance liquid chromatography, direct ionization mass spectrometry, X-ray diffractometry, stable isotope analysis) and botanical investigations were performed. Results Counterfeit artesunate containing chloroquine, counterfeit dihydroartemisinin (DHA) containing paracetamol (acetaminophen), counterfeit DHA-piperaquine containing sildenafil, counterfeit artemether-lumefantrine containing pyrimethamine, counterfeit halofantrine containing artemisinin, and substandard/counterfeit or degraded artesunate and artesunate+amodiaquine in eight countries are described. Pollen analysis was consistent with manufacture of counterfeits in eastern Asia. These data do not allow estimation of the frequency of poor quality anti-malarials in Africa. Conclusions Criminals are producing diverse harmful anti-malarial counterfeits with important public health consequences. The presence of artesunate monotherapy, substandard and/or degraded and counterfeit medicines containing sub-therapeutic amounts of unexpected anti-malarials will engender drug resistance. With the threatening spread of artemisinin resistance to Africa, much greater investment is required to ensure the quality of ACTs and removal of artemisinin monotherapies. The International Health Regulations may need to be invoked to counter these serious public health problems. PMID:22152094

Poor Decision Making is Associated with an Increased Risk of Mortality Among Community-Dwelling Older Persons without Dementia

PubMed Central

Boyle, Patricia A.; Wilson, Robert S.; Yu, Lei; Buchman, Aron S.; Bennett, David A.

2013-01-01

Background Decision making is thought to be an important determinant of health and well-being across the lifespan, but little is known about the association of decision making with mortality. Methods Participants were 675 older persons without dementia from the Rush Memory and Aging Project, a longitudinal cohort study of aging. Baseline assessments of decision making were used to predict the risk of mortality during up to 4 years of follow-up. Results The mean score on the decision making measure at baseline was 7.1 (SD=2.9, range: 0-12), with lower scores indicating poorer decision making. During up to 4 years of follow-up (mean=1.7 years), 40 (6% of 675) persons died. In a proportional hazards model adjusted for age, sex, and education, the risk of mortality increased by about 20% for each additional decision making error (HR=1.19, 95% CI 1.07, 1.32, p=0.002). Thus, a person who performed poorly on the measure of decision making (score=3, 10th percentile) was about four times more likely to die compared to a person who performed well (score=11, 90th percentile). Further, the association of decision making with mortality persisted after adjustment for the level of cognitive function. Conclusion Poor decision making is associated with an increased risk of mortality in old age even after accounting for cognitive function. PMID:23364306

A MODIFIED LOW COST COLOURIMETRIC METHOD FOR PARACETAMOL (ACETAMINOPHEN) MEASUREMENT IN PLASMA

PubMed Central

Shihana, Fathima; Dissanayake, Dhammika Menike; Dargan, Paul Ivor; Dawson, Andrew Hamilton

2011-01-01

Background Despite a significant increase in the number of patients with paracetamol poisoning in the developing world, plasma paracetamol assays are not widely available. The purpose of this study was to assess a low cost modified colorimetric paracetamol assay that has the potential to be performed in small laboratories with restricted resources. Methods The paracetamol assay used in this study was based on the Glynn and Kendal colorimetric method with a few modifications in order to decrease the production of nitrous gas and thereby reduce infrastructure costs. Preliminary validation studies were performed using spiked aqueous samples with known concentrations of paracetamol. Subsequently, the results from the colorimetric method for 114 stored clinical samples from patients with paracetamol poisoning were compared with those from the current gold-standard high-performance liquid chromatography (HPLC) method. A prospective survey, assessing the clinical use of the paracetamol assay, was performed on all patients with paracetamol poisoning attending the Peradeniya General Hospital, Sri Lanka over a ten-month period. Results The recovery study showed an excellent correlation (r2 >0.998) for paracetamol concentrations from 25- 400 mg/l. The final yellow colour was stable for at least 10 minutes at room temperature. There was also excellent correlation with the HPLC method (r2=0.9758). In the clinical cohort study, use of the antidote N-acetylcysteine was avoided in over a third of patients who had a plasma paracetamol concentration measured. The cost of consumables used per assay was $0.50 (US). Conclusions This colorimetric paracetamol assay is reliable and accurate and can be performed rapidly, easily and economically. Use of this assay in resource poor clinical settings has the potential to have a significant clinical and economic impact on the management of paracetamol poisoning. PMID:20095813

Radon-domain interferometric interpolation for reconstruction of the near-offset gap in marine seismic data

NASA Astrophysics Data System (ADS)

Xu, Zhuo; Sopher, Daniel; Juhlin, Christopher; Han, Liguo; Gong, Xiangbo

2018-04-01

In towed marine seismic data acquisition, a gap between the source and the nearest recording channel is typical. Therefore, extrapolation of the missing near-offset traces is often required to avoid unwanted effects in subsequent data processing steps. However, most existing interpolation methods perform poorly when extrapolating traces. Interferometric interpolation methods are one particular method that have been developed for filling in trace gaps in shot gathers. Interferometry-type interpolation methods differ from conventional interpolation methods as they utilize information from several adjacent shot records to fill in the missing traces. In this study, we aim to improve upon the results generated by conventional time-space domain interferometric interpolation by performing interferometric interpolation in the Radon domain, in order to overcome the effects of irregular data sampling and limited source-receiver aperture. We apply both time-space and Radon-domain interferometric interpolation methods to the Sigsbee2B synthetic dataset and a real towed marine dataset from the Baltic Sea with the primary aim to improve the image of the seabed through extrapolation into the near-offset gap. Radon-domain interferometric interpolation performs better at interpolating the missing near-offset traces than conventional interferometric interpolation when applied to data with irregular geometry and limited source-receiver aperture. We also compare the interferometric interpolated results with those obtained using solely Radon transform (RT) based interpolation and show that interferometry-type interpolation performs better than solely RT-based interpolation when extrapolating the missing near-offset traces. After data processing, we show that the image of the seabed is improved by performing interferometry-type interpolation, especially when Radon-domain interferometric interpolation is applied.

Advancing hypoxic training in team sports: from intermittent hypoxic training to repeated sprint training in hypoxia

PubMed Central

Faiss, Raphaël; Girard, Olivier; Millet, Grégoire P

2013-01-01

Over the past two decades, intermittent hypoxic training (IHT), that is, a method where athletes live at or near sea level but train under hypoxic conditions, has gained unprecedented popularity. By adding the stress of hypoxia during ‘aerobic’ or ‘anaerobic’ interval training, it is believed that IHT would potentiate greater performance improvements compared to similar training at sea level. A thorough analysis of studies including IHT, however, leads to strikingly poor benefits for sea-level performance improvement, compared to the same training method performed in normoxia. Despite the positive molecular adaptations observed after various IHT modalities, the characteristics of optimal training stimulus in hypoxia are still unclear and their functional translation in terms of whole-body performance enhancement is minimal. To overcome some of the inherent limitations of IHT (lower training stimulus due to hypoxia), recent studies have successfully investigated a new training method based on the repetition of short (<30 s) ‘all-out’ sprints with incomplete recoveries in hypoxia, the so-called repeated sprint training in hypoxia (RSH). The aims of the present review are therefore threefold: first, to summarise the main mechanisms for interval training and repeated sprint training in normoxia. Second, to critically analyse the results of the studies involving high-intensity exercises performed in hypoxia for sea-level performance enhancement by differentiating IHT and RSH. Third, to discuss the potential mechanisms underpinning the effectiveness of those methods, and their inherent limitations, along with the new research avenues surrounding this topic. PMID:24282207

Processing time tolerance-based ACO algorithm for solving job-shop scheduling problem

NASA Astrophysics Data System (ADS)

Luo, Yabo; Waden, Yongo P.

2017-06-01

Ordinarily, Job Shop Scheduling Problem (JSSP) is known as NP-hard problem which has uncertainty and complexity that cannot be handled by a linear method. Thus, currently studies on JSSP are concentrated mainly on applying different methods of improving the heuristics for optimizing the JSSP. However, there still exist many problems for efficient optimization in the JSSP, namely, low efficiency and poor reliability, which can easily trap the optimization process of JSSP into local optima. Therefore, to solve this problem, a study on Ant Colony Optimization (ACO) algorithm combined with constraint handling tactics is carried out in this paper. Further, the problem is subdivided into three parts: (1) Analysis of processing time tolerance-based constraint features in the JSSP which is performed by the constraint satisfying model; (2) Satisfying the constraints by considering the consistency technology and the constraint spreading algorithm in order to improve the performance of ACO algorithm. Hence, the JSSP model based on the improved ACO algorithm is constructed; (3) The effectiveness of the proposed method based on reliability and efficiency is shown through comparative experiments which are performed on benchmark problems. Consequently, the results obtained by the proposed method are better, and the applied technique can be used in optimizing JSSP.

Consequences of self-handicapping: effects on coping, academic performance, and adjustment.

PubMed

Zuckerman, M; Kieffer, S C; Knee, C R

1998-06-01

Self-handicappers erect impediments to performance to protect their self-esteem. The impediments may interfere with the ability to do well and, as such, may result in poor adjustment. Using a longitudinal design, the present studies examined prospective effects of self-handicapping on coping, academic performance, and several adjustment-related variables (e.g., self-esteem). It was found that, compared to low self-handicappers, high self-handicappers reported higher usage of coping strategies implying withdrawal and negative focus. High self-handicappers performed less well academically, an effect that was mediated in part by poor study habits. Finally, high self-handicapping resulted in poorer adjustment over time, and poorer adjustment resulted in higher self-handicapping over time. These relations are consistent with the idea of a vicious cycle in which self-handicapping and poor adjustment reinforce one another.

A DBN based anomaly targets detector for HSI

NASA Astrophysics Data System (ADS)

Ma, Ning; Wang, Shaojun; Yu, Jinxiang; Peng, Yu

2017-10-01

Due to the assumption that Hyperspectral image (HSI) should conform to Gaussian distribution, traditional Mahalanobis distance-based anomaly targets detectors perform poor because the assumption may not always hold. In order to solve those problems, a deep learning based detector, Deep Belief Network(DBN) anomaly detector(DBN-AD), was proposed to fit the unknown distribution of HSI by energy modeling, the reconstruction errors of this encode-decode processing are used for discriminating the anomaly targets. Experiments are implemented on real and synthesized HSI dataset which collection by Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS). Comparing to classic anomaly detector, the proposed method shows better performance, it performs about 0.17 higher in Area Under ROC Curve (AUC) than that of Reed-Xiaoli detector(RXD) and Kernel-RXD (K-RXD).

The limits of low-temperature performance of Li-ion cells

NASA Technical Reports Server (NTRS)

Huang, C.; Sakamoto, J.; Wolfenstine, J.; Surampudi, S.

2000-01-01

The results of electrode and electrolyte studies reveal that the poor low-temperature (<-30 degrees C) performance of Li-ion cells is mainly caused by the carbon electrodes and not the organic electrolytes and solid electrolyte interphase, as previously suggested. It is suggested that the main causes for the poor performance in the carbon electrodes are (i) the low value and concentration depedence of the Li diffusivity and (ii) limited Li capacity.

Language Profiles of Poor Comprehenders in English and French

ERIC Educational Resources Information Center

D'Angelo, Nadia; Chen, Xi

2017-01-01

This study explored components of language comprehension (vocabulary, grammar, and higher-level language) skills for poor comprehenders in French immersion. We identified three groups of bilingual comprehenders (poor, average, and good) based on English reading performance and compared their language comprehension skills in English L1 and French…

Improvements of the offshore earthquake locations in the Earthquake Early Warning System

NASA Astrophysics Data System (ADS)

Chen, Ta-Yi; Hsu, Hsin-Chih

2017-04-01

Since 2014 the Earthworm Based Earthquake Alarm Reporting (eBEAR) system has been operated and been used to issue warnings to schools. In 2015 the system started to provide warnings to the public in Taiwan via television and the cell phone. Online performance of the eBEAR system indicated that the average reporting times afforded by the system are approximately 15 and 28 s for inland and offshore earthquakes, respectively. The eBEAR system in average can provide more warning time than the current EEW system (3.2 s and 5.5 s for inland and offshore earthquakes, respectively). However, offshore earthquakes were usually located poorly because only P-wave arrivals were used in the eBEAR system. Additionally, in the early stage of the earthquake early warning system, only fewer stations are available. The poor station coverage may be a reason to answer why offshore earthquakes are difficult to locate accurately. In the Geiger's inversion procedure of earthquake location, we need to put an initial hypocenter and origin time into the location program. For the initial hypocenter, we defined some test locations on the offshore area instead of using the average of locations from triggered stations. We performed 20 programs concurrently running the Geiger's method with different pre-defined initial position to locate earthquakes. We assume that if the program with the pre-defined initial position is close to the true earthquake location, during the iteration procedure of the Geiger's method the processing time of this program should be less than others. The results show that using pre-defined locations for trial-hypocenter in the inversion procedure is able to improve the accurate of offshore earthquakes. Especially for EEW system, in the initial stage of the EEW system, only use 3 or 5 stations to locate earthquakes may lead to bad results because of poor station coverage. In this study, the pre-defined trial-locations provide a feasible way to improve the estimations of earthquake locations in EEW system.

An adaptive optics imaging system designed for clinical use

PubMed Central

Zhang, Jie; Yang, Qiang; Saito, Kenichi; Nozato, Koji; Williams, David R.; Rossi, Ethan A.

2015-01-01

Here we demonstrate a new imaging system that addresses several major problems limiting the clinical utility of conventional adaptive optics scanning light ophthalmoscopy (AOSLO), including its small field of view (FOV), reliance on patient fixation for targeting imaging, and substantial post-processing time. We previously showed an efficient image based eye tracking method for real-time optical stabilization and image registration in AOSLO. However, in patients with poor fixation, eye motion causes the FOV to drift substantially, causing this approach to fail. We solve that problem here by tracking eye motion at multiple spatial scales simultaneously by optically and electronically integrating a wide FOV SLO (WFSLO) with an AOSLO. This multi-scale approach, implemented with fast tip/tilt mirrors, has a large stabilization range of ± 5.6°. Our method consists of three stages implemented in parallel: 1) coarse optical stabilization driven by a WFSLO image, 2) fine optical stabilization driven by an AOSLO image, and 3) sub-pixel digital registration of the AOSLO image. We evaluated system performance in normal eyes and diseased eyes with poor fixation. Residual image motion with incremental compensation after each stage was: 1) ~2–3 arc minutes, (arcmin) 2) ~0.5–0.8 arcmin and, 3) ~0.05–0.07 arcmin, for normal eyes. Performance in eyes with poor fixation was: 1) ~3–5 arcmin, 2) ~0.7–1.1 arcmin and 3) ~0.07–0.14 arcmin. We demonstrate that this system is capable of reducing image motion by a factor of ~400, on average. This new optical design provides additional benefits for clinical imaging, including a steering subsystem for AOSLO that can be guided by the WFSLO to target specific regions of interest such as retinal pathology and real-time averaging of registered images to eliminate image post-processing. PMID:26114033

Improving semi-automated segmentation by integrating learning with active sampling

NASA Astrophysics Data System (ADS)

Huo, Jing; Okada, Kazunori; Brown, Matthew

2012-02-01

Interactive segmentation algorithms such as GrowCut usually require quite a few user interactions to perform well, and have poor repeatability. In this study, we developed a novel technique to boost the performance of the interactive segmentation method GrowCut involving: 1) a novel "focused sampling" approach for supervised learning, as opposed to conventional random sampling; 2) boosting GrowCut using the machine learned results. We applied the proposed technique to the glioblastoma multiforme (GBM) brain tumor segmentation, and evaluated on a dataset of ten cases from a multiple center pharmaceutical drug trial. The results showed that the proposed system has the potential to reduce user interaction while maintaining similar segmentation accuracy.

Chaotic homes and school achievement: a twin study

PubMed Central

Hanscombe, Ken B; Haworth, Claire MA; Davis, Oliver SP; Jaffee, Sara R; Plomin, Robert

2011-01-01

Background Chaotic homes predict poor school performance. Given that it is known that genes affect both children's experience of household chaos and their school achievement, to what extent is the relationship between high levels of noise and environmental confusion in the home, and children's school performance, mediated by heritable child effects? This is the first study to explore the genetic and environmental pathways between household chaos and academic performance. Method Children's perceptions of family chaos at ages 9 and 12 and their school performance at age 12 were assessed in more than 2,300 twin pairs. The use of child-specific measures in a multivariate genetic analysis made it possible to investigate the genetic and environmental origins of the covariation between children's experience of chaos in the home and their school achievement. Results Children's experience of family chaos and their school achievement were significantly correlated in the expected negative direction (r = −.26). As expected, shared environmental factors explained a large proportion (63%) of the association. However, genetic factors accounted for a significant proportion (37%) of the association between children's experience of household chaos and their school performance. Conclusions The association between chaotic homes and poor performance in school, previously assumed to be entirely environmental in origin, is in fact partly genetic. How children's home environment affects their academic achievement is not simply in the direction environment → child → outcome. Instead, genetic factors that influence children's experience of the disordered home environment also affect how well they do at school. The relationship between the child, their environment and their performance at school is complex: both genetic and environmental factors play a role. PMID:21675992

Cross-evaluation of ground-based, multi-satellite and reanalysis precipitation products: Applicability of the Triple Collocation method across Mainland China

NASA Astrophysics Data System (ADS)

Li, Changming; Tang, Guoqiang; Hong, Yang

2018-07-01

Evaluating the reliability of satellite and reanalysis precipitation products is critical but challenging over ungauged or poorly gauged regions. The Triple Collocation (TC) method is a reliable approach to estimate the accuracy of any three independent inputs in the absence of truth values. This study assesses the uncertainty of three types of independent precipitation products, i.e., satellite-based, ground-based and model reanalysis over Mainland China using the TC method. The ground-based data set is Gauge Based Daily Precipitation Analysis (CGDPA). The reanalysis data set is European Reanalysis Agency Reanalysis Product (ERA-interim). The satellite-based products include five mainstream satellite products. The comparison and evaluation are conducted at 0.25° and daily resolutions from 2013 to 2015. First, the effectiveness of the TC method is evaluated in South China with dense gauge network. The results demonstrate that the TC method is reliable because the correlation coefficient (CC) and root mean square error (RMSE) derived from TC are close to those derived from ground observations, with only 9% and 7% mean relative differences, respectively. Then, the TC method is applied in Mainland China, with special attention paid to the Tibetan Plateau (TP) known as the Earth's third pole with few ground stations. Results indicate that (1) The overall performance of IMERG is better than the other satellite products over Mainland China, followed by 3B42V7, CMORPH-CRT and PERSIANN-CDR. (2) In the TP, CGDPA shows the best overall performance over gauged grid cells, however, over ungauged regions, IMERG and ERA-interim slightly outperform CGDPA with similar RMSE but higher mean CC (0.63, 0.61, and 0.58, respectively). It highlights the strengths and potentiality of remote sensing and reanalysis data over the TP and reconfirms the cons of the inherent uncertainty of CGDPA due to interpolation from sparsely gauged data. The study concludes that the TC method provides not only reliable cross-validation results over Mainland China but also a new perspective for comparatively assessing multi-source precipitation products, particularly over poorly gauged regions such as the TP.

Training to improve manual control in 7-8 and 10-12 year old children: Training eliminates performance differences between ages.

PubMed

Snapp-Childs, Winona; Fath, Aaron J; Watson, Carol A; Flatters, Ian; Mon-Williams, Mark; Bingham, Geoffrey P

2015-10-01

Many children have difficulty producing movements well enough to improve in perceptuo-motor learning. We have developed a training method that supports active movement generation to allow improvement in a 3D tracing task requiring good compliance control. We previously tested 7-8 year old children who exhibited poor performance and performance differences before training. After training, performance was significantly improved and performance differences were eliminated. According to the Dynamic Systems Theory of development, appropriate support can enable younger children to acquire the ability to perform like older children. In the present study, we compared 7-8 and 10-12 year old school children and predicted that younger children would show reduced performance that was nonetheless amenable to training. Indeed, the pre-training performance of the 7-8 year olds was worse than that of the 10-12 year olds, but post-training performance was equally good for both groups. This was similar to previous results found using this training method for children with DCD and age-matched typically developing children. We also found in a previous study of 7-8 year old school children that training in the 3D tracing task transferred to a 2D drawing task. We now found similar transfer for the 10-12 year olds. Copyright © 2015 Elsevier B.V. All rights reserved.

A novel alignment-free method for detection of lateral genetic transfer based on TF-IDF.

PubMed

Cong, Yingnan; Chan, Yao-Ban; Ragan, Mark A

2016-07-25

Lateral genetic transfer (LGT) plays an important role in the evolution of microbes. Existing computational methods for detecting genomic regions of putative lateral origin scale poorly to large data. Here, we propose a novel method based on TF-IDF (Term Frequency-Inverse Document Frequency) statistics to detect not only regions of lateral origin, but also their origin and direction of transfer, in sets of hierarchically structured nucleotide or protein sequences. This approach is based on the frequency distributions of k-mers in the sequences. If a set of contiguous k-mers appears sufficiently more frequently in another phyletic group than in its own, we infer that they have been transferred from the first group to the second. We performed rigorous tests of TF-IDF using simulated and empirical datasets. With the simulated data, we tested our method under different parameter settings for sequence length, substitution rate between and within groups and post-LGT, deletion rate, length of transferred region and k size, and found that we can detect LGT events with high precision and recall. Our method performs better than an established method, ALFY, which has high recall but low precision. Our method is efficient, with runtime increasing approximately linearly with sequence length.

Sparse Method for Direction of Arrival Estimation Using Denoised Fourth-Order Cumulants Vector.

PubMed

Fan, Yangyu; Wang, Jianshu; Du, Rui; Lv, Guoyun

2018-06-04

Fourth-order cumulants (FOCs) vector-based direction of arrival (DOA) estimation methods of non-Gaussian sources may suffer from poor performance for limited snapshots or difficulty in setting parameters. In this paper, a novel FOCs vector-based sparse DOA estimation method is proposed. Firstly, by utilizing the concept of a fourth-order difference co-array (FODCA), an advanced FOCs vector denoising or dimension reduction procedure is presented for arbitrary array geometries. Then, a novel single measurement vector (SMV) model is established by the denoised FOCs vector, and efficiently solved by an off-grid sparse Bayesian inference (OGSBI) method. The estimation errors of FOCs are integrated in the SMV model, and are approximately estimated in a simple way. A necessary condition regarding the number of identifiable sources of our method is presented that, in order to uniquely identify all sources, the number of sources K must fulfill K ≤ ( M 4 - 2 M 3 + 7 M 2 - 6 M ) / 8 . The proposed method suits any geometry, does not need prior knowledge of the number of sources, is insensitive to associated parameters, and has maximum identifiability O ( M 4 ) , where M is the number of sensors in the array. Numerical simulations illustrate the superior performance of the proposed method.

Contextual Factors Related to Math Anxiety in Second-Grade Children

ERIC Educational Resources Information Center

Jameson, Molly M.

2014-01-01

As the United States falls farther behind other countries in standardized math assessments, the author seeks to understand why U.S. students perform so poorly. One of the possible explanations to U.S. students' poor math performance may be math anxiety. However, math anxiety in elementary school children is a neglected area in the research. The…

The Effects of Knowledge of Criterion Task on Comprehension and Recall in Normally Achieving and Learning Disabled Children.

ERIC Educational Resources Information Center

Wong, Bernice Y. L.; And Others

1982-01-01

A study investigated the hypothesis that poor comprehension or recall of task demands, rather than a putative lack of goal directedness, is a possible source of learning-disabled children's poor performance of experimental tasks. Clear instructions substantially facilitated performance by both normally achieving and learning disabled children of…

Investigating Sentence Processing and Language Segmentation in Explaining Children's Performance on a Sentence-Span Task

ERIC Educational Resources Information Center

Mainela-Arnold, Elina; Misra, Maya; Miller, Carol; Poll, Gerard H.; Park, Ji Sook

2012-01-01

Background: Children with poor language abilities tend to perform poorly on verbal working memory tasks. This result has been interpreted as evidence that limitations in working memory capacity may interfere with the development of a mature linguistic system. However, it is possible that language abilities, such as the efficiency of sentence…

The Effect of Script on Poor Readers' Sensitivity to Dynamic Visual Stimuli

ERIC Educational Resources Information Center

Kim, Jeesun; Davis, Chris; Burnham, Denis; Luksaneeyanawin, Sudaporn

2004-01-01

The current research examined performance of good and poor readers of Thai on two tasks that assess sensitivity to dynamic visual displays. Readers of Thai, a complex alphabetic script that nonetheless has a regular orthography, were chosen in order to contrast patterns of performance with readers of Korean Hangul (a similarly regular language but…

Is the United States Really Losing the International Horse Race in Academic Achievement?

ERIC Educational Resources Information Center

Boe, Erling E.; Shin, Sujie

2005-01-01

It is widely believed and lamented that U.S. students perform poorly on international comparisons of academic achievement. For example, Edward Silver reports that U.S. seventh- and eighth-grade students performed poorly on the mathematics section of the Third International Mathematics and Science Study (TIMSS 1995) and that this indicates "a…

Pediatric hepatic hemangiosarcoma in a rhesus macaque (Macaca mulatta)

PubMed Central

Mejía, A.F.; Gierbolini, L.; Jacob, B.; Westmoreland, S.V.

2009-01-01

Background Pediatric hepatic angiosarcoma is a rare condition in children with poor prognosis. Microscopically this neoplasm has a particular ‘Kaposi-form’ arrangement. Hemangiosarcoma in non-human primates is a rare finding. Methods Gross and microscopic examination of a 3-year-old rhesus were performed. Immunohistochemistry was used to characterize the hepatic hemangiosarcoma. Results The gross necropsy revealed hemoabdomen and a 4 × 3 × 3 cm mass in the liver with multiple smaller masses throughout the hepatic parenchyma. Histopathology confirmed a poorly differentiated hemangiosarcoma. Other organs submitted were free of metastases. Conclusions Hemangiosarcoma in non-human primates has been rarely reported. Diagnosis was confirmed by expression of endothelial-specific markers CD31 and vWF by immunohistochemistry. Due to the young age of this monkey and the particular solid pattern throughout the mass this neoplasm resembles pediatric hepatic angiosarcoma in humans. PMID:18671765

An Approach to 3d Digital Modeling of Surfaces with Poor Texture by Range Imaging Techniques. `SHAPE from Stereo' VS. `SHAPE from Silhouette' in Digitizing Jorge Oteiza's Sculptures

NASA Astrophysics Data System (ADS)

García Fernández, J.; Álvaro Tordesillas, A.; Barba, S.

2015-02-01

Despite eminent development of digital range imaging techniques, difficulties persist in the virtualization of objects with poor radiometric information, in other words, objects consisting of homogeneous colours (totally white, black, etc.), repetitive patterns, translucence, or materials with specular reflection. This is the case for much of the Jorge Oteiza's works, particularly in the sculpture collection of the Museo Fundación Jorge Oteiza (Navarra, Spain). The present study intend to analyse and asses the performance of two digital 3D-modeling methods based on imaging techniques, facing cultural heritage in singular cases, determined by radiometric characteristics as mentioned: Shape from Silhouette and Shape from Stereo. On the other hand, the text proposes the definition of a documentation workflow and presents the results of its application in the collection of sculptures created by Oteiza.

Closing the poor-rich gap in contraceptive use in urban Kenya: are family planning programs increasingly reaching the urban poor?

PubMed

Fotso, Jean Christophe; Speizer, Ilene S; Mukiira, Carol; Kizito, Paul; Lumumba, Vane

2013-08-27

Kenya is characterized by high unmet need for family planning (FP) and high unplanned pregnancy, in a context of urban population explosion and increased urban poverty. It witnessed an improvement of its FP and reproductive health (RH) indicators in the recent past, after a period of stalled progress. The objectives of the paper are to: a) describe inequities in modern contraceptive use, types of methods used, and the main sources of contraceptives in urban Kenya; b) examine the extent to which differences in contraceptive use between the poor and the rich widened or shrank over time; and c) attempt to relate these findings to the FP programming context, with a focus on whether the services are increasingly reaching the urban poor. We use data from the 1993, 1998, 2003 and 2008/09 Kenya demographic and health survey. Bivariate analyses describe the patterns of modern contraceptive use and the types and sources of methods used, while multivariate logistic regression models assess how the gap between the poor and the rich varied over time. The quantitative analysis is complemented by a review on the major FP/RH programs carried out in Kenya. There was a dramatic change in contraceptive use between 2003 and 2008/09 that resulted in virtually no gap between the poor and the rich in 2008/09, by contrast to the period 1993-1998 during which the improvement in contraceptive use did not significantly benefit the urban poor. Indeed, the late 1990s marked the realization by the Government of Kenya and its development partners, of the need to deliberately target the poor with family planning services. Most urban women use short-term and less effective methods, with the proportion of long-acting method users dropping by half during the review period. The proportion of private sector users also declined between 2003 and 2008/09. The narrowing gap in the recent past between the urban poor and the urban rich in the use of modern contraception is undoubtedly good news, which, coupled with the review of the family program context, suggests that family planning programs may be increasingly reaching the urban poor.

Cognitive performance after mild traumatic brain injury: the impact of poor effort on test results and its relation to distress, personality and litigation.

PubMed

Stulemeijer, Maja; Andriessen, Teuntje M J C; Brauer, Jolanda M P; Vos, Pieter E; Van Der Werf, Sieberen

2007-03-01

To compare consecutive Mild Traumatic Brain Injury (MTBI) patients with and without adequate effort on cognitive performance, litigation status, fatigue, distress and personality. (Neuro)psychological assessment was done 6 months post-injury in 110 patients from a cohort of 618 consecutive MTBI patients aged 18-60, who attended the emergency department of our level I trauma centre. Effort was tested with the Amsterdam Short Term Memory test. Thirty patients (27%) failed the effort test. Poor effort was associated with significantly poorer scores on seven out of eleven measures, covering all tested domains. Poor effort was associated with lower educational level and changes in work status, but not litigation. Furthermore, poor effort was related to high levels of distress, Type-D personality and fatigue. Even in a sample of non-referred MTBI patients, poor effort was common and was strongly associated with inferior test performance. These findings imply that effort testing should be part of all cognitive assessments, also outside mediolegal settings. Behavioural factors like distress and personality should be considered as potential threats to the validity of neuropsychological testing after MTBI.

Hydrocephalus

MedlinePlus

... lethargy Nausea or vomiting Unstable balance Poor coordination Poor appetite Seizures Urinary incontinence Behavioral and cognitive changes Irritability Change in personality Decline in school performance Delays or problems with previously acquired skills, such ...

Making great leaps forward: Accounting for detectability in herpetological field studies

USGS Publications Warehouse

Mazerolle, Marc J.; Bailey, Larissa L.; Kendall, William L.; Royle, J. Andrew; Converse, Sarah J.; Nichols, James D.

2007-01-01

Detecting individuals of amphibian and reptile species can be a daunting task. Detection can be hindered by various factors such as cryptic behavior, color patterns, or observer experience. These factors complicate the estimation of state variables of interest (e.g., abundance, occupancy, species richness) as well as the vital rates that induce changes in these state variables (e.g., survival probabilities for abundance; extinction probabilities for occupancy). Although ad hoc methods (e.g., counts uncorrected for detection, return rates) typically perform poorly in the face of no detection, they continue to be used extensively in various fields, including herpetology. However, formal approaches that estimate and account for the probability of detection, such as capture-mark-recapture (CMR) methods and distance sampling, are available. In this paper, we present classical approaches and recent advances in methods accounting for detectability that are particularly pertinent for herpetological data sets. Through examples, we illustrate the use of several methods, discuss their performance compared to that of ad hoc methods, and we suggest available software to perform these analyses. The methods we discuss control for imperfect detection and reduce bias in estimates of demographic parameters such as population size, survival, or, at other levels of biological organization, species occurrence. Among these methods, recently developed approaches that no longer require marked or resighted individuals should be particularly of interest to field herpetologists. We hope that our effort will encourage practitioners to implement some of the estimation methods presented herein instead of relying on ad hoc methods that make more limiting assumptions.

Multidimensional deconvolution of optical microscope and ultrasound imaging using adaptive least-mean-square (LMS) inverse filtering

NASA Astrophysics Data System (ADS)

Sapia, Mark Angelo

2000-11-01

Three-dimensional microscope images typically suffer from reduced resolution due to the effects of convolution, optical aberrations and out-of-focus blurring. Two- dimensional ultrasound images are also degraded by convolutional bluffing and various sources of noise. Speckle noise is a major problem in ultrasound images. In microscopy and ultrasound, various methods of digital filtering have been used to improve image quality. Several methods of deconvolution filtering have been used to improve resolution by reversing the convolutional effects, many of which are based on regularization techniques and non-linear constraints. The technique discussed here is a unique linear filter for deconvolving 3D fluorescence microscopy or 2D ultrasound images. The process is to solve for the filter completely in the spatial-domain using an adaptive algorithm to converge to an optimum solution for de-blurring and resolution improvement. There are two key advantages of using an adaptive solution: (1)it efficiently solves for the filter coefficients by taking into account all sources of noise and degraded resolution at the same time, and (2)achieves near-perfect convergence to the ideal linear deconvolution filter. This linear adaptive technique has other advantages such as avoiding artifacts of frequency-domain transformations and concurrent adaptation to suppress noise. Ultimately, this approach results in better signal-to-noise characteristics with virtually no edge-ringing. Many researchers have not adopted linear techniques because of poor convergence, noise instability and negative valued data in the results. The methods presented here overcome many of these well-documented disadvantages and provide results that clearly out-perform other linear methods and may also out-perform regularization and constrained algorithms. In particular, the adaptive solution is most responsible for overcoming the poor performance associated with linear techniques. This linear adaptive approach to deconvolution is demonstrated with results of restoring blurred phantoms for both microscopy and ultrasound and restoring 3D microscope images of biological cells and 2D ultrasound images of human subjects (courtesy of General Electric and Diasonics, Inc.).

Children's catching performance when the demands on the postural system is altered.

PubMed

Angelakopoulos, Georgios T; Tsorbatzoudis, Haralambos; Grouios, George

2014-07-01

In many dynamic interceptive actions performers need to integrate activity of manual and postural subsystems for successful performance. Groups of different skill level (poor and good catchers), (mean age = 9.1 and 9.4 respectively) were required to perform one-handed catches under different postural constraints: standing; standing in contact with a postural support aid by their side (PSAS) or to the left of their trunk (PSAF); Tandem; and sitting (control). Results revealed that, for poor catchers, the number of successful catches increased and grasp errors decreased significantly when sitting and with both postural aids in comparison with standing alone and Tandem conditions. Kinematic analyses showed that the postural aid devices reduced head sway in the anterior-posterior direction, while the PSAF reduced lateral head sway. The poor catchers' performance benefited from an enlarged support surface, and reduction of lateral sway. Good catchers performed successfully under all task constraints, signifying the existence of a functional relationship between postural and grasping subsystems during performance. The results are discussed in the frame of Bernstein's (1967) and Newell's (1986) theory.

Self-affirmation among the poor: cognitive and behavioral implications.

PubMed

Hall, Crystal C; Zhao, Jiaying; Shafir, Eldar

2014-02-01

The poor are universally stigmatized. The stigma of poverty includes being perceived as incompetent and feeling shunned and disrespected. It can lead to cognitive distancing, diminish cognitive performance, and cause the poor to forego beneficial programs. In the present research, we examined how self-affirmation can mitigate the stigma of poverty through randomized field experiments involving low-income individuals at an inner-city soup kitchen. Because of low literacy levels, we used an oral rather than written affirmation procedure, in which participants verbally described a personal experience that made them feel successful or proud. Compared with nonaffirmed participants, affirmed individuals exhibited better executive control, higher fluid intelligence, and a greater willingness to avail themselves of benefits programs. The effects were not driven by elevated positive mood, and the same intervention did not affect the performance of wealthy participants. The findings suggest that self-affirmation can improve the cognitive performance and decisions of the poor, and it may have important policy implications.

Evaluating simplified methods for liquefaction assessment for loss estimation

NASA Astrophysics Data System (ADS)

Kongar, Indranil; Rossetto, Tiziana; Giovinazzi, Sonia

2017-06-01

Currently, some catastrophe models used by the insurance industry account for liquefaction by applying a simple factor to shaking-induced losses. The factor is based only on local liquefaction susceptibility and this highlights the need for a more sophisticated approach to incorporating the effects of liquefaction in loss models. This study compares 11 unique models, each based on one of three principal simplified liquefaction assessment methods: liquefaction potential index (LPI) calculated from shear-wave velocity, the HAZUS software method and a method created specifically to make use of USGS remote sensing data. Data from the September 2010 Darfield and February 2011 Christchurch earthquakes in New Zealand are used to compare observed liquefaction occurrences to forecasts from these models using binary classification performance measures. The analysis shows that the best-performing model is the LPI calculated using known shear-wave velocity profiles, which correctly forecasts 78 % of sites where liquefaction occurred and 80 % of sites where liquefaction did not occur, when the threshold is set at 7. However, these data may not always be available to insurers. The next best model is also based on LPI but uses shear-wave velocity profiles simulated from the combination of USGS VS30 data and empirical functions that relate VS30 to average shear-wave velocities at shallower depths. This model correctly forecasts 58 % of sites where liquefaction occurred and 84 % of sites where liquefaction did not occur, when the threshold is set at 4. These scores increase to 78 and 86 %, respectively, when forecasts are based on liquefaction probabilities that are empirically related to the same values of LPI. This model is potentially more useful for insurance since the input data are publicly available. HAZUS models, which are commonly used in studies where no local model is available, perform poorly and incorrectly forecast 87 % of sites where liquefaction occurred, even at optimal thresholds. This paper also considers two models (HAZUS and EPOLLS) for estimation of the scale of liquefaction in terms of permanent ground deformation but finds that both models perform poorly, with correlations between observations and forecasts lower than 0.4 in all cases. Therefore these models potentially provide negligible additional value to loss estimation analysis outside of the regions for which they have been developed.

Rapid and Accurate Diagnosis of Acute Pyogenic Meningitis Due to Streptococcus Pneumoniae, Haemophilus influenzae Type b and Neisseria meningitidis Using A Multiplex PCR Assay.

PubMed

Seth, Rajeev; Murthy, Peela Sree Ramchandra; Sistla, Sujatha; Subramanian, Mahadevan; Tamilarasu, Kadhiravan

2017-09-01

Acute bacterial meningitis is one of the major causes of morbidity and mortality in children and geriatric population, especially in developing countries. Methods of identification are standard culture and other phenotypic tests in many resource poor settings. To use molecular methods for the improvement of aetiological diagnosis of acute pyogenic meningitis in patients. CSF samples of 125 patients were included for the study. Gram staining and culture were performed according to standard procedures. Antigen was detected using commercial latex agglutination test kit. Multiplex PCR was performed using previously published primers and protocols. Fischer's exact test was used for finding association between presence of the disease and clinical/biochemical parameters, considering two tailed p<0.05 as statistically significant. Sensitivity, specificity, positive and negative predictive values were calculated using Graphpad QuicCalc software. A total of 39 cases (31.2%) were confirmed to be of acute pyogenic meningitis based on biochemical methods. Only 10/39 was positive for the three organisms tested. Multiplex PCR was able to detect one additional isolate each of Streptococcus pneumoniae and Haemophilus influenzae type b. When compared with multiplex PCR as the gold standard, culture and latex agglutination tests had same sensitivity (80%), specificity (100%), PPV (100%) and NPV (97.8%), whereas Gram stain had poor sensitivity (40%) and good specificity (95.6%). Detection rates were higher in multiplex PCR for the two organisms Streptococcus pneumoniae and Haemophilus influenzae type b. Multiplex PCR was more sensitive than culture or antigen detection, and employing this assay can significantly increase the speed and accuracy of identification of the pathogen.

Predictors of medical school clerkship performance: a multispecialty longitudinal analysis of standardized examination scores and clinical assessments.

PubMed

Casey, Petra M; Palmer, Brian A; Thompson, Geoffrey B; Laack, Torrey A; Thomas, Matthew R; Hartz, Martha F; Jensen, Jani R; Sandefur, Benjamin J; Hammack, Julie E; Swanson, Jerry W; Sheeler, Robert D; Grande, Joseph P

2016-04-27

Evidence suggests that poor performance on standardized tests before and early in medical school is associated with poor performance on standardized tests later in medical school and beyond. This study aimed to explore relationships between standardized examination scores (before and during medical school) with test and clinical performance across all core clinical clerkships. We evaluated characteristics of 435 students at Mayo Medical School (MMS) who matriculated 2000-2009 and for whom undergraduate grade point average, medical college aptitude test (MCAT), medical school standardized tests (United States Medical Licensing Examination [USMLE] 1 and 2; National Board of Medical Examiners [NBME] subject examination), and faculty assessments were available. We assessed the correlation between scores and assessments and determined USMLE 1 cutoffs predictive of poor performance (≤10th percentile) on the NBME examinations. We also compared the mean faculty assessment scores of MMS students vs visiting students, and for the NBME, we determined the percentage of MMS students who scored at or below the tenth percentile of first-time national examinees. MCAT scores correlated robustly with USMLE 1 and 2, and USMLE 1 and 2 independently predicted NBME scores in all clerkships. USMLE 1 cutoffs corresponding to poor NBME performance ranged from 220 to 223. USMLE 1 scores were similar among MMS and visiting students. For most academic years and clerkships, NBME scores were similar for MMS students vs all first-time examinees. MCAT, USMLE 1 and 2, and subsequent clinical performance parameters were correlated with NBME scores across all core clerkships. Even more interestingly, faculty assessments correlated with NBME scores, affirming patient care as examination preparation. USMLE 1 scores identified students at risk of poor performance on NBME subject examinations, facilitating and supporting implementation of remediation before the clinical years. MMS students were representative of medical students across the nation.

Presentation and outcome of clinical poor performance in one health district over a 5-year period: 2002-2007.

PubMed

Cox, Stephen J; Holden, John D

2009-05-01

The detection, assessment, and management of primary care poor performance raise difficult issues for all those involved. Guidance has largely focused on managing the most serious cases where patient safety is severely compromised. The management of primary care poor performance has become an increasingly important part of primary care trust (PCT) work, but its modes of presentation and prevalence are not well known. To report the prevalence, presentation modes, and management of primary care poor performance cases presenting to one PCT over a 5-year period. A retrospective review of primary care poor performance cases in one district. St Helens PCT administered 35 practices with 130 GPs on the performers list, caring for 190 110 patients in North West England, UK. Cases presenting during 2002-2007 were initially reviewed by the chair of the PCT clinical executive committee. Anonymised data were then jointly reviewed by the assessor and another experienced GP advisor. There were 102 individual presentations (20 per year or one every 2-3 weeks) where clinician performance raised significant cause for concern occurred over the 5-year period. These concerns related to 37 individual clinicians, a range of 1-14 per clinician (mean 2.7). Whistleblowing by professional colleagues on 43 occasions was the most common presentation, of which 26 were from GPs about GPs. Patient complaints (18) were the second most common presentation. Twenty-seven clinicians were GPs, of whom the General Medical Council (GMC) were notified or involved in 13 cases. Clinicians were supported locally, and remedying was exclusively locally managed in 14 cases, and shared with an external organisation (such as the GMC or deanery) in another 12. Professional whistleblowing and patient complaints were the most common sources of presentation. Effective PCT teams are needed to manage clinicians whose performance gives cause for concern. Sufficient resources and both formal and informal ways of reporting concerns are essential.

Impact of poor sleep quality and physical inactivity on cognitive function in community-dwelling older adults.

PubMed

Nakakubo, Sho; Makizako, Hyuma; Doi, Takehiko; Tsutsumimoto, Kota; Lee, Sangyoon; Lee, Sungchul; Hotta, Ryo; Bae, Seongryu; Suzuki, Takao; Shimada, Hiroyuki

2017-11-01

The purpose of the present study was to examine whether the combination of subjective sleep quality and physical activity is associated with cognitive performance among community-dwelling older adults. Cross-sectional data on 5381 older adults who participated in part of the National Center for Geriatrics and Gerontology - Study of Geriatric Syndromes were analyzed. We assessed general cognitive impairment using the Mini-Mental State Examination, and also assessed story memory, attention, executive function and processing speed using the National Center for Geriatrics and Gerontology Functional Assessment Tool. Physical activity was assessed using two questionnaires, and participants were categorized as active or inactive. Sleep quality was assessed using the Pittsburgh Sleep Quality Index, and participants were categorized as having poor (PS) or good sleep quality (GS). Participants in the inactive + PS group had worse performances than those in the active + GS group in all cognitive measures (Mini-Mental State Examination: P = 0.008, story memory: P = 0.007, other cognitive measures: P < 0.001), and also had worse performances than those in the inactive + GS and active + PS groups in the trail-making test, part B, and the symbol digit substitution test (P < 0.001, respectively). Additionally, participants in the inactive + GS group had worse performances than in the active + GS in the trail-making test, part B, and the symbol digit substitution test (P = 0.002 and P = 0.001, respectively). Inactivity and poor sleep quality were associated with poor cognitive performance among community-dwelling older adults. The combination of poor sleep quality and physical inactivity also worsened cognitive performance. Geriatr Gerontol Int 2017; 17: 1823-1828. © 2017 Japan Geriatrics Society.

Iliac artery stenting in patients with poor distal runoff: Influence of concomitant infrainguinal arterial reconstruction.

PubMed

Timaran, Carlos H; Ohki, Takao; Gargiulo, Nicholas J; Veith, Frank J; Stevens, Scott L; Freeman, Michael B; Goldman, Mitchell H

2003-09-01

Inadequate infrainguinal runoff is considered an important risk factor for iliac stent failure. However, the influence of concomitant infrainguinal arterial reconstruction (CIAR) on iliac stent patency is unknown. This study evaluated the influence of CIAR on outcome of iliac angioplasty and stenting (IAS) in patients with poor distal runoff. Over 5 years (1996 to 2001), 68 IAS procedures (78 stents) were performed in 62 patients with poor distal runoff (angiographic runoff score >or=5). The SVS/AAVS reporting standards were followed to define outcome variables and risk factors. Data were analyzed with both univariate analysis (Kaplan-Meier method [K-M]) and regression analysis (Cox proportional hazards model). Indications for iliac artery stenting were disabling claudication (59%) and limb salvage (41%). Of the 68 procedures, IAS with CIAR was performed in 31 patients (46%), and IAS alone was performed in 37 patients (54%). Patients undergoing IAS with CIAR were older (P =.03) and had more extensive and multifocal iliac artery occlusive disease, with more TASC (TransAtlantic Inter-Society Consensus) type C lesions (P =.03), compared with patients undergoing IAS alone. No other significant differences in risk factors were noted. Runoff scores between patients undergoing IAS with CIAR and those undergoing IAS alone were not significantly different (median runoff scores, 6 [range, 5-8] and 7 [range, 5-9], respectively; P =.77). Primary stent patency rate at 1, 3, and 5 years was 87%, 54%, and 42%, respectively, for patients undergoing IAS with CIAR, and was 76%, 66%, and 55%, respectively, for patients undergoing IAS. Univariate analysis revealed that primary stent patency rate was not significantly different between the 2 groups (K-M, log-rank test, P =.81). Primary graft patency rate for CIAR was 81%, 52%, and 46% at 1, 3, and 5 years, respectively. Performing CIAR did not affect primary iliac stent patency (relative risk, 1.1; 95% confidence interval, 0.49-2.47; P =.81). Overall, there was a trend toward improved limb salvage in patients undergoing IAS with CIAR, compared with those undergoing IAS alone (K-M, log rank test, P =.07). In patients undergoing IAS with poor distal runoff, CIAR does not improve iliac artery stent patency. Infrainguinal bypass procedures should therefore be reserved for patients who do not demonstrate clinical improvement and possibly for those with limb-threatening ischemia.

Open-loop-feedback control of serum drug concentrations: pharmacokinetic approaches to drug therapy.

PubMed

Jelliffe, R W

1983-01-01

Recent developments to optimize open-loop-feedback control of drug dosage regimens, generally applicable to pharmacokinetically oriented therapy with many drugs, involve computation of patient-individualized strategies for obtaining desired serum drug concentrations. Analyses of past therapy are performed by least squares, extended least squares, and maximum a posteriori probability Bayesian methods of fitting pharmacokinetic models to serum level data. Future possibilities for truly optimal open-loop-feedback therapy with full Bayesian methods, and conceivably for optimal closed-loop therapy in such data-poor clinical situations, are also discussed. Implementation of these various therapeutic strategies, using automated, locally controlled infusion devices, has also been achieved in prototype form.

Bilateral adrenal histoplasmosis: endoscopic ultrasound-guided fine needle aspiration as a method of diagnosis and assessment.

PubMed

Azhar, J Khairul; Jacqueline, H S G; Tony, L K H; Tan, B H; Steven, J M

2011-12-01

We report a case of a healthy 78-year-old indonesian man who presented with chronic weight loss, poor appetite and lethargy. CT abdomen showed bilateral adrenal masses. EUS-guided FNA was performed on the left adrenal gland. Histopathology report was Histoplasma Capsulatum. He recovered well with antifungal treatment without any complication. In this case, we found that the role of EUS -guided FNA was not only limited to diagnosis but also helped in the prognosis of the disease since the method was able to assess the general anatomy of the adrenal gland better than other imaging modalities due to its close proximity and direct visualization.

Creep rupture of polymer-matrix composites

NASA Technical Reports Server (NTRS)

Brinson, H. F.; Morris, D. H.; Griffith, W. I.

1981-01-01

The time-dependent creep-rupture process in graphite-epoxy laminates is examined as a function of temperature and stress level. Moisture effects are not considered. An accelerated characterization method of composite-laminate viscoelastic modulus and strength properties is reviewed. It is shown that lamina-modulus master curves can be obtained using a minimum of normally performed quality-control-type testing. Lamina-strength master curves, obtained by assuming a constant-strain-failure criterion, are presented along with experimental data, and reasonably good agreement is shown to exist between the two. Various phenomenological delayed failure models are reviewed and two (the modified rate equation and the Larson-Miller parameter method) are compared to creep-rupture data with poor results.

The mirror neuron system: a neural substrate for methods in stroke rehabilitation.

PubMed

Garrison, Kathleen A; Winstein, Carolee J; Aziz-Zadeh, Lisa

2010-06-01

Mirror neurons found in the premotor and parietal cortex respond not only during action execution, but also during observation of actions being performed by others. Thus, the motor system may be activated without overt movement. Rehabilitation of motor function after stroke is often challenging due to severity of impairment and poor to absent voluntary movement ability. Methods in stroke rehabilitation based on the mirror neuron system--action observation, motor imagery, and imitation--take advantage of this opportunity to rebuild motor function despite impairments, as an alternative or complement to physical therapy. Here the authors review research into each condition of practice, and discuss the relevance of the mirror neuron system to stroke recovery.

An improved method for characterizing photoresist lithographic and defectivity performance for sub-20nm node lithography

NASA Astrophysics Data System (ADS)

Amblard, Gilles; Purdy, Sara; Cooper, Ryan; Hockaday, Marjory

2016-03-01

The overall quality and processing capability of lithographic materials are critical for ensuring high device yield and performance at sub-20nm technology nodes in a high volume manufacturing environment. Insufficient process margin and high line width roughness (LWR) cause poor manufacturing control, while high defectivity causes product failures. In this paper, we focus on the most critical layer of a sub-20nm technology node LSI device, and present an improved method for characterizing both lithographic and post-patterning defectivity performance of state-of-the-art immersion photoresists. Multiple formulations from different suppliers were used and compared. Photoresists were tested under various process conditions, and multiple lithographic metrics were investigated (depth of focus, exposure dose latitude, line width roughness, etc.). Results were analyzed and combined using an innovative approach based on advanced software, providing clearer results than previously available. This increased detail enables more accurate performance comparisons among the different photoresists. Post-patterning defectivity was also quantified, with defects reviewed and classified using state-of-the-art inspection tools. Correlations were established between the lithographic and post-patterning defectivity performances for each material, and overall ranking was established among the photoresists, enabling the selection of the best performer for implementation in a high volume manufacturing environment.

Cognitive performance is associated with macronutrient intake in healthy young and middle-aged adults.

PubMed

Zhang, Jian; Mckeown, Robert E; Muldoon, Matthew F; Tang, Shenghui

2006-01-01

The objective was to examine whether dietary intakes of macronutrients are associated with neuropsychological performance. Study participants were 3960 adults aged 20-59 years, who completed three neuropsychological tests and a 24-hour dietary recall as a part of the Third National Health and Nutrition Examination Survey, 1988-1994. Poor performance was defined as the test score below gender-specific 15th percentile. While holding the energy percentages from different macronutrients, additional 100 kcal intake of energy was associated with a reduced odds of poor performance on serial digital learning test (OR = 0.98, 95% CI = 0.96, 0.99) and symbol digital substitution test (OR = 0.97, 95% CI = 0.96, 0.99). Compared with equivalent energy from carbohydrates, each 5% of energy from poly-unsaturated fatty acids (PUFA) or total fat was associated with a reduced OR of poor performance on simple reaction time test (PUFA: OR = 0.77, 95% CI = 0.63-0.95 and total fat: OR = 0.93, 95% CI = 0.87, 0.99). Poor global cognition was associated with an additional intake of 100 mg cholesterol (OR = 1.14, 95% CI = 1.05, 1.23). These associations were more salient in men. Habitual intake of macronutrients is weakly but significantly associated with cognitive functioning. These relationships are more evident in men.

Encoding of Spatial Attention by Primate Prefrontal Cortex Neuronal Ensembles

PubMed Central

Treue, Stefan

2018-01-01

Abstract Single neurons in the primate lateral prefrontal cortex (LPFC) encode information about the allocation of visual attention and the features of visual stimuli. However, how this compares to the performance of neuronal ensembles at encoding the same information is poorly understood. Here, we recorded the responses of neuronal ensembles in the LPFC of two macaque monkeys while they performed a task that required attending to one of two moving random dot patterns positioned in different hemifields and ignoring the other pattern. We found single units selective for the location of the attended stimulus as well as for its motion direction. To determine the coding of both variables in the population of recorded units, we used a linear classifier and progressively built neuronal ensembles by iteratively adding units according to their individual performance (best single units), or by iteratively adding units based on their contribution to the ensemble performance (best ensemble). For both methods, ensembles of relatively small sizes (n < 60) yielded substantially higher decoding performance relative to individual single units. However, the decoder reached similar performance using fewer neurons with the best ensemble building method compared with the best single units method. Our results indicate that neuronal ensembles within the LPFC encode more information about the attended spatial and nonspatial features of visual stimuli than individual neurons. They further suggest that efficient coding of attention can be achieved by relatively small neuronal ensembles characterized by a certain relationship between signal and noise correlation structures. PMID:29568798

The Specific Role of Inhibition in Reading Comprehension in Good and Poor Comprehenders

ERIC Educational Resources Information Center

Borella, Erika; Carretti, Barbara; Pelegrina, Santiago

2010-01-01

Difficulties in inhibitory processes have been shown to characterize the performance of poor comprehenders. However, the inhibitory inefficiency of poor comprehenders is most often assessed by their resistance to proactive interference, that is, the ability to suppress off-goal task information from working memory (WM). In two studies tasks…

The Affordable Housing Crisis: Residential Mobility of Poor Families and School Mobility of Poor Children.

ERIC Educational Resources Information Center

Crowley, Sheila

2003-01-01

Helping poor families increase their residential stability can have direct bearing on school stability and student academic achievement. Discusses the role of housing in child and family wellbeing; residential mobility and school performance; residential mobility and housing problems; housing affordability; (federal housing policy); homeownership;…

A Customized Attention-Based Long Short-Term Memory Network for Distant Supervised Relation Extraction.

PubMed

He, Dengchao; Zhang, Hongjun; Hao, Wenning; Zhang, Rui; Cheng, Kai

2017-07-01

Distant supervision, a widely applied approach in the field of relation extraction can automatically generate large amounts of labeled training corpus with minimal manual effort. However, the labeled training corpus may have many false-positive data, which would hurt the performance of relation extraction. Moreover, in traditional feature-based distant supervised approaches, extraction models adopt human design features with natural language processing. It may also cause poor performance. To address these two shortcomings, we propose a customized attention-based long short-term memory network. Our approach adopts word-level attention to achieve better data representation for relation extraction without manually designed features to perform distant supervision instead of fully supervised relation extraction, and it utilizes instance-level attention to tackle the problem of false-positive data. Experimental results demonstrate that our proposed approach is effective and achieves better performance than traditional methods.

Planning a sports training program using Adaptive Particle Swarm Optimization with emphasis on physiological constraints.

PubMed

Kumyaito, Nattapon; Yupapin, Preecha; Tamee, Kreangsak

2018-01-08

An effective training plan is an important factor in sports training to enhance athletic performance. A poorly considered training plan may result in injury to the athlete, and overtraining. Good training plans normally require expert input, which may have a cost too great for many athletes, particularly amateur athletes. The objectives of this research were to create a practical cycling training plan that substantially improves athletic performance while satisfying essential physiological constraints. Adaptive Particle Swarm Optimization using ɛ-constraint methods were used to formulate such a plan and simulate the likely performance outcomes. The physiological constraints considered in this study were monotony, chronic training load ramp rate and daily training impulse. A comparison of results from our simulations against a training plan from British Cycling, which we used as our standard, showed that our training plan outperformed the benchmark in terms of both athletic performance and satisfying all physiological constraints.

Challenging ocular image recognition

NASA Astrophysics Data System (ADS)

Pauca, V. Paúl; Forkin, Michael; Xu, Xiao; Plemmons, Robert; Ross, Arun A.

2011-06-01

Ocular recognition is a new area of biometric investigation targeted at overcoming the limitations of iris recognition performance in the presence of non-ideal data. There are several advantages for increasing the area beyond the iris, yet there are also key issues that must be addressed such as size of the ocular region, factors affecting performance, and appropriate corpora to study these factors in isolation. In this paper, we explore and identify some of these issues with the goal of better defining parameters for ocular recognition. An empirical study is performed where iris recognition methods are contrasted with texture and point operators on existing iris and face datasets. The experimental results show a dramatic recognition performance gain when additional features are considered in the presence of poor quality iris data, offering strong evidence for extending interest beyond the iris. The experiments also highlight the need for the direct collection of additional ocular imagery.

Inferior vena cava segmentation with parameter propagation and graph cut.

PubMed

Yan, Zixu; Chen, Feng; Wu, Fa; Kong, Dexing

2017-09-01

The inferior vena cava (IVC) is one of the vital veins inside the human body. Accurate segmentation of the IVC from contrast-enhanced CT images is of great importance. This extraction not only helps the physician understand its quantitative features such as blood flow and volume, but also it is helpful during the hepatic preoperative planning. However, manual delineation of the IVC is time-consuming and poorly reproducible. In this paper, we propose a novel method to segment the IVC with minimal user interaction. The proposed method performs the segmentation block by block between user-specified beginning and end masks. At each stage, the proposed method builds the segmentation model based on information from image regional appearances, image boundaries, and a prior shape. The intensity range and the prior shape for this segmentation model are estimated based on the segmentation result from the last block, or from user- specified beginning mask if at first stage. Then, the proposed method minimizes the energy function and generates the segmentation result for current block using graph cut. Finally, a backward tracking step from the end of the IVC is performed if necessary. We have tested our method on 20 clinical datasets and compared our method to three other vessel extraction approaches. The evaluation was performed using three quantitative metrics: the Dice coefficient (Dice), the mean symmetric distance (MSD), and the Hausdorff distance (MaxD). The proposed method has achieved a Dice of [Formula: see text], an MSD of [Formula: see text] mm, and a MaxD of [Formula: see text] mm, respectively, in our experiments. The proposed approach can achieve a sound performance with a relatively low computational cost and a minimal user interaction. The proposed algorithm has high potential to be applied for the clinical applications in the future.

A Temporal Locality-Aware Page-Mapped Flash Translation Layer

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

Kim, Youngjae; Gupta, Aayush; Urgaonkar, Bhuvan

2013-01-01

The poor performance of random writes has been a cause of major concern which needs to be addressed to better utilize the potential of flash in enterprise-scale environments. We examine one of the important causes of this poor performance: the design of the flash translation layer (FTL) which performs the virtual-to-physical address translations and hides the erase-before-write characteristics of flash. We propose a complete paradigm shift in the design of the core FTL engine from the existing techniques with our Demand-Based Flash Translation Layer (DFTL) which selectively caches page- level address mappings. Our experimental evaluation using FlashSim with realistic enterprise-scalemore » workloads endorses the utility of DFTL in enterprise-scale storage systems by demonstrating: 1) improved performance, 2) reduced garbage collection overhead and 3) better overload behavior compared with hybrid FTL schemes which are the most popular implementation methods. For example, a predominantly random-write dominant I/O trace from an OLTP application running at a large financial institution shows a 78% improvement in average response time (due to a 3-fold reduction in operations of the garbage collector), compared with the hybrid FTL scheme. Even for the well-known read-dominant TPC-H benchmark, for which DFTL introduces additional overheads, we improve system response time by 56%. Moreover, interestingly, when write-back cache on DFTL-based SSD is enabled, DFTL even outperforms the page-based FTL scheme, improving their response time by 72% in Financial trace.« less

Comparison of reading and listening-reading techniques for administration of PIAT Reading Comprehension subtest: justification for the bypass approach.

PubMed

Weinberg, W A; McLean, A; Brumback, R A

1988-04-01

The Peabody Individual Achievement Test (PIAT) Reading Comprehension subtest was administered to a group of 23 learning disabled children in Grades 5 through 7 who had been classified by the clinical Lexical Paradigm as good readers or poor readers. Using standardized test administration, 14 poor readers scored substantially below the 9 good readers; however, when the child was allowed to listen and read silently while the test item was read aloud, poor readers showed marked improvement in performance compared to only moderate improvement shown by the good readers. This difference in improvement between the groups was significant and resulted in poor readers achieving performance similar to that of the good readers administered the test in the standard manner.

SLEEP QUALITY AND ITS ASSOCIATION WITH PSYCHOLOGICAL SYMPTOMS IN ADOLESCENT ATHLETES

PubMed Central

Gomes, Gabriel Cordeiro; dos Passos, Muana Hiandra Pereira; Silva, Hítalo Andrade; de Oliveira, Valéria Mayaly Alves; Novaes, Wbinayara Alves; Pitangui, Ana Carolina Rodarti; de Araújo, Rodrigo Cappato

2017-01-01

ABSTRACT Objective: To verify the prevalence of poor sleep quality and its association with personal characteristics and symptoms of depression, anxiety and stress in amateur adolescent athletes. Methods: 309 adolescent athletes aged between 10 and 19 years were enrolled. Data collection included: a structured questionnaire, with personal information; the Pittsburgh Sleep Quality Index (PSQI); and the Depression, Anxiety and Stress Scale (DASS-21). Results are described in mean and standard deviation (numeric variables) and absolute and relative frequencies (categorical variables). For the inferential analysis, Student’s t-test and chi-square test were performed, in addition to Poisson regression. Prevalence ratios (PR) were calculated in a 95% confidence interval (95%CI). Results: The mean age of participants was 14.1±2.1, being 13.8±2.0 and 15.0±2.1, respectively, for those with good and poor sleep quality. Poor sleep quality was recorded in 28.2% (n=87), depression in 26.9% (n=83) and anxiety/stress in 40.1% (n=124). Poor sleep quality was associated with ages between 15 and 19 years (PR 1.24; 95%CI 1.14-1.37), overweight (PR 1.12; 95%CI 1.01-1.24) and psychological symptoms of depression (PR 1.23; 95%CI 1.08-1.40) and anxiety/stress (PR 1.16; 95%CI 1.04-1.28). Conclusions: The presence of overweight and psychological symptoms and the age over 15 years were risk factors for increasing the likelihood of poor sleep quality in adolescent athletes. PMID:28977294

Association between depression and glycemic control among type 2 diabetes patients in Lima, Peru

PubMed Central

Crispín‐Trebejo, Brenda; Bernabé‐Ortiz, Antonio

2015-01-01

Abstract Introduction There is limited and controversial information regarding the potential impact of depression on glycemic control. This study aims to evaluate the association between depression and poor glycemic control. In addition, the prevalence of depression and rates of poor glycemic control were determined. Methods Cross‐sectional study performed in the endocrinology unit of two hospitals of ESSALUD in Peru. The outcome of interest was poor glycemic control, evaluated by glycated hemoglobin (HbA1c: < 7% versus ≥ 7%), whereas the exposure of interest was depression defined as 15 or more points in the Patient Health Questionnaire‐9 tool. The association of interest was evaluated using Poisson regression models with robust standard errors reporting prevalence ratios (PR) and 95% confidence intervals (95% CI) adjusting for potential confounders. Results A total of 277 participants, 184 (66.4%) males, mean age 59.0 (SD: 4.8), and 7.1 (SD: 6.8) years of disease were analyzed. Only 31 participants (11.2%; 95% CI: 7.5%–14.9%) had moderately severe or severe depression, whereas 70 (25.3%; 95% CI 20.3%–30.8%) had good glycemic control. Depression increased the probability of having poor glycemic control (PR = 1.32; 95% CI 1.15–1.51) after adjusting for several potential confounders. Conclusions There is an association between depression and poor glycemic control among type 2 diabetes patients. Our results suggest that early detection of depression might be important to facilitate appropriate glycemic control and avoid further metabolic complications. PMID:26037488

Physical Aggression and Language Ability from 17 to 72 Months: Cross-Lagged Effects in a Population Sample

PubMed Central

Girard, Lisa-Christine; Pingault, Jean-Baptiste; Falissard, Bruno; Boivin, Michel; Dionne, Ginette; Tremblay, Richard E.

2014-01-01

Background Does poor language ability in early childhood increase the likelihood of physical aggression or is language ability delayed by frequent physical aggression? This study examined the longitudinal associations between physical aggression and language ability from toddlerhood to early childhood in a population sample while controlling for parenting behaviours, non-verbal intellectual functioning, and children’s sex. Methods Children enrolled in the Quebec Longitudinal Study of Child Development (QLSCD) (N = 2, 057) were assessed longitudinally from 17 to 72 months via parent reports and standardized assessments. Results The cross-lagged models revealed modest reciprocal associations between physical aggression and language performance from 17 to 41 months but not thereafter. Conclusions Significant associations between physical aggression and poor language ability are minimal and limited to the period when physical aggression and language performance are both substantially increasing. During that period parenting behaviours may play an important role in supporting language ability while reducing the frequency of physical aggression. Further studies are needed that utilize multiple assessments of physical aggression, assess multiple domains of language abilities, and that examine the potential mediating role of parenting behaviours between 12 and 48 months. PMID:25375971

A national survey of cardiac rehabilitation services in New Zealand: 2015.

PubMed

Kira, Geoff; Doolan-Noble, Fiona; Humphreys, Grace; Williams, Gina; O'Shaughnessy, Helen; Devlin, Gerry

2016-05-27

Guidelines for cardiac rehabilitation (CR) programmes inform best practice. In Aotearoa NewZealand, little information exists about the structure and services provided by CR programmes and there is a poor understanding of how existing CR programmes are delivered with respect to evidence-based national guidelines. All 46 CR providers in New Zealand were invited to participate in a national survey in 2015. The survey sought information on the following: unit structure; referral processes; patient assessment; audit (including quality assurance activity); Phase 2 CR content; and support for special populations. Simple descriptive analysis of the responses was conducted, involving forming counts and percentages. Thirty-six distinct units completed the survey and 94% provided Phase 2. Assessment tools, Phase 2 educational components, and the methods of providing the exercise component varied. Most units audited their services, 25% audited their programme six-monthly or more frequently. Just over half of the units (56%) reported key performance indicators. The survey identified variations in delivery and content of CR in New Zealand, with poor understanding of the impact on patient outcomes. This is likely due to the absence of standardised audit practices and routine collection of key performance indicators on a national basis.

Applied kinesiology methods for a 10-year-old child with headaches, neck pain, asthma, and reading disabilities

PubMed Central

Cuthbert, Scott; Rosner, Anthony

2010-01-01

Objective The purpose of this case report is to describe the chiropractic care of a 10-year-old boy who presented with developmental delay syndromes, asthma, and chronic neck and head pain and to present an overview of his muscular imbalances during manual muscle testing evaluation that guided the interventions offered to this child. Clinical Features The child was a poor reader, suffered eye strain while reading, had poor memory for classroom material, and was unable to move easily from one line of text to another during reading. He was using 4 medications for the asthma but was still symptomatic during exercise. Intervention and Outcome Chiropractic care, using applied kinesiology, guided evaluation, and treatment. Following spinal and cranial treatment, the patient showed improvement in his reading ability, head and neck pain, and respiratory distress. His ability to read improved (in 3 weeks, after 5 treatments), performing at his own grade level. He has remained symptom free for 2 years. Conclusion The care provided to this patient seemed to help resolve his chronic musculoskeletal dysfunction and pain and improve his academic performance. PMID:22027037

Biliary access in technically difficult biliary cannulation: the mucosal bridge technique

PubMed Central

Thomas, Rebecca; Shah, Suhaila Rizal; Worthley, Christopher S

2009-01-01

Background: The use of precut sphincterotomy during endoscopic retrograde cholangiopancreatography (ERCP) facilitates selective bile duct access in difficult procedures. However, it is also associated with high rates of complications. Several techniques for precut sphincterotomy have been described in the literature. This paper reports our experience with a non-needle-knife technique for precut sphincterotomy, namely, the mucosal bridge technique. Methods: We analysed the experience of a single surgical endoscopist at our centre in performing precut sphincterotomies by retrospectively examining information in the database for January 2002 to February 2008, which had been stored prospectively using Endoscribe. Results: The mucosal bridge technique was performed in 16 (3.19%) of 501 patients. Success rates were 75% and 100% after first and second ERCPs, respectively. The failure of initial procedures was caused by bleeding, tissue oedema, poorly visualized papilla or a poorly distensible duodenum and oedematous papilla. There were four cases of complications, which included periductular extravasation of contrast, bleeding, and sepsis in two patients. However, these complications were not a direct consequence of the precut sphincterotomy. Conclusions: The mucosal bridge technique can be used to increase the likelihood of successful bile duct cannulation, thus preventing the need for a second intervention. PMID:19590645

Sensitivity to gaze-contingent contrast increments in naturalistic movies: An exploratory report and model comparison

PubMed Central

Wallis, Thomas S. A.; Dorr, Michael; Bex, Peter J.

2015-01-01

Sensitivity to luminance contrast is a prerequisite for all but the simplest visual systems. To examine contrast increment detection performance in a way that approximates the natural environmental input of the human visual system, we presented contrast increments gaze-contingently within naturalistic video freely viewed by observers. A band-limited contrast increment was applied to a local region of the video relative to the observer's current gaze point, and the observer made a forced-choice response to the location of the target (≈25,000 trials across five observers). We present exploratory analyses showing that performance improved as a function of the magnitude of the increment and depended on the direction of eye movements relative to the target location, the timing of eye movements relative to target presentation, and the spatiotemporal image structure at the target location. Contrast discrimination performance can be modeled by assuming that the underlying contrast response is an accelerating nonlinearity (arising from a nonlinear transducer or gain control). We implemented one such model and examined the posterior over model parameters, estimated using Markov-chain Monte Carlo methods. The parameters were poorly constrained by our data; parameters constrained using strong priors taken from previous research showed poor cross-validated prediction performance. Atheoretical logistic regression models were better constrained and provided similar prediction performance to the nonlinear transducer model. Finally, we explored the properties of an extended logistic regression that incorporates both eye movement and image content features. Models of contrast transduction may be better constrained by incorporating data from both artificial and natural contrast perception settings. PMID:26057546

Measuring cognitive load: mixed results from a handover simulation for medical students.

PubMed

Young, John Q; Irby, David M; Barilla-LaBarca, Maria-Louise; Ten Cate, Olle; O'Sullivan, Patricia S

2016-02-01

The application of cognitive load theory to workplace-based activities such as patient handovers is hindered by the absence of a measure of the different load types. This exploratory study tests a method for measuring cognitive load during handovers. The authors developed the Cognitive Load Inventory for Handoffs (CLI4H) with items for intrinsic, extraneous, and germane load. Medical students completed the measure after participating in a simulated handover. Exploratory factor and correlation analyses were performed to collect evidence for validity. Results yielded a two-factor solution for intrinsic and germane load that explained 50 % of the variance. The extraneous load items performed poorly and were removed from the model. The score for intrinsic load correlated with the Paas Cognitive Load scale (r = 0.31, p = 0.004) and was lower for students with more prior handover training (p = 0.036). Intrinsic load did not, however, correlate with performance. Germane load did not correlate with the Paas Cognitive Load scale but did correlate as expected with performance (r = 0.30, p = 0.005) and was lower for those students with more prior handover training (p = 0.03). The CLI4H yielded mixed results with some evidence for validity of the score from the intrinsic load items. The extraneous load items performed poorly and the use of only a single item for germane load limits conclusions. The instrument requires further development and testing. Study results and limitations provide guidance to future efforts to measure cognitive load during workplace-based activities, such as handovers.

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

Wang, Qiannan; Zhu, Ding; Zhou, Wanhai

Highlights: • Effects of four different preparation processes were studied at 20/60 °C. • All NS + HT, RS and RS + HT processes can optimize the thermodynamic performance. • The HT process can provoke the precipitation of A{sub 2}B{sub 7} and leads to a poor cycling life. • Al exhibits the most remarkable dissolution for all the alloys, especially at 60 °C. - Abstract: In order to optimize the microstructure and high temperature electrochemical performances of low-cost AB{sub 5}-type Ml(NiMnAl){sub 4.2}Co{sub 0.3}Fe{sub 0.5} hydrogen storage electrode alloys, four different preparation methods including normal solidification (NS), normal solidification and 900more » °C heat treatment (NS + HT), rapid solidification (RS), rapid solidification and 900 °C heat treatment (RS + HT) were adopted in this work. All alloys exhibit CaCu{sub 5} type hexagonal structure and there is a small amount of A{sub 2}B{sub 7} phase in NS + HT and RS + HT alloys. It is found the using of HT process can decrease the hydrogen equilibrium plateau pressure, the plateau slope and hysteresis at 40, 60 and 80 °C. The NS + HT and RS + HT alloys also possess better activation, high rate discharge performance, larger discharge capacity, but poor cycling performance due to the existence of A{sub 2}B{sub 7} phase which can accelerate dissolution of Ni, Mn and Fe elements in KOH alkaline electrolyte. The RS process can make alloy exhibit the best cycling performance especially at 60 °C.« less

Variations in Oncologist Recommendations for Chemotherapy for Stage IV Lung Cancer: What Is the Role of Performance Status?

PubMed

Tisnado, Diana; Malin, Jennifer; Kahn, Katherine; Landrum, Mary Beth; Fletcher, Robert; Klabunde, Carrie; Clauser, Steven; Rogers, Selwyn O; Keating, Nancy L

2016-07-01

Chemotherapy prolongs survival in patients with advanced non-small-cell lung cancer. However, few studies have included patients with poor performance status. This study examined rates of oncologists' recommendations for chemotherapy by patient performance status and symptoms and how physician characteristics influence chemotherapy recommendations. We surveyed medical oncologists involved in the care of a population-based cohort of patients with lung cancer from the CanCORS (Cancer Care Outcomes Research and Surveillance) study. Physicians were queried about their likelihood to recommend chemotherapy to patients with stage IV lung cancer with varying performance status (Eastern Cooperative Oncology Group performance status 0 [good] v 3 [poor]) and presence or absence of tumor-related pain. Repeated measures logistic regression was used to estimate the independent associations of patients' performance status and symptoms and physicians' demographic and practice characteristics with chemotherapy recommendations. Nearly all physicians (adjusted rate, 97% to 99%) recommended chemotherapy for patients with good performance status, and approximately half (adjusted rate, 38% to 53%) recommended chemotherapy for patients with poor performance status (P < .001). Compared with patient factors, physician and practice characteristics were less strongly associated with chemotherapy recommendations in adjusted analyses. Strong consensus among oncologists exists for chemotherapy in patients with advanced non-small-cell lung cancer and good performance status. However, the relatively high rate of chemotherapy recommendations for patients with poor performance status despite the unfavorable risk-benefit profile highlights the need for ongoing work to define high-value care in oncology and to implement and evaluate strategies to align incentives for such care. Copyright © 2016 by American Society of Clinical Oncology.

Performance in College Chemistry: a Statistical Comparison Using Gender and Jungian Personality Type

NASA Astrophysics Data System (ADS)

Greene, Susan V.; Wheeler, Henry R.; Riley, Wayne D.

This study sorted college introductory chemistry students by gender and Jungian personality type. It recognized differences from the general population distribution and statistically compared the students' grades with their Jungian personality types. Data from 577 female students indicated that ESFP (extroverted, sensory, feeling, perceiving) and ENFP (extroverted, intuitive, feeling, perceiving) profiles performed poorly at statistically significant levels when compared with the distribution of females enrolled in introductory chemistry. The comparable analysis using data from 422 male students indicated that the poorly performing male profiles were ISTP (introverted, sensory, thinking, perceiving) and ESTP (extroverted, sensory, thinking, perceiving). ESTJ (extroverted, sensory, thinking, judging) female students withdrew from the course at a statistically significant level. For both genders, INTJ (introverted, intuitive, thinking, judging) students were the best performers. By examining the documented characteristics of Jungian profiles that correspond with poorly performing students in chemistry, one may more effectively assist the learning process and the retention of these individuals in the fields of natural science, engineering, and technology.

GIS diagnostics: thermal imaging systems used for poor contact detection

NASA Astrophysics Data System (ADS)

Avital, Doron; Brandenbursky, V.; Farber, A.

2004-04-01

The reliability of GIS is very high but any failure that occurs can cause extensive damage result and the repair times are considerably long. The consequential losses to system security and economically can be high, especially if the nominal GIS voltage is 420 kV and above. In view of these circumstances, increasing attention is being given to diagnostic techniques for in-service maintenance undertaken to improve the reliability and availability of GIS. Recently considerable progress has been made in diagnostic techniques and they are now used successfully during the service life of the equipment. These diagnostic techniques in general focus on the GIS insulation system and are based on partial discharge (PD) measurements in GIS. There are three main methods for in-service PD detection in GIS: - the chemical method that rely on the detection of cracked gas caused by PD, the acoustic method designed to detect the acoustic emission excited by PD, and, the electrical method which is based on detection of electrical resonance at ultra high frequencies (UHF) up to 1.5 GHz caused by PD excitation in GIS chambers (UHF method). These three dielectric diagnostic methods cannot be used for the detection of poor current carrying contacts in GIS. This problem does not always produce partial discharges and at early stages it does not cause gas cracking. An interesting solution to use two techniques - the current unbalance alarm scheme and partial discharge monitoring was advised by A. Salinas from South California Edison Co. Unfortunately this way is complicated and very expensive. The investigations performed in Japan on standing alone SF6 breaker showed that joule heating of the contact accompanied by released power of 1600 Watt produce temperature difference on the enclosure up to 7 degrees centigrade that could be detected by infra-red Thermal Imaging System. According to CIGRE Joint Working Group 33/23.12 Report, 11% of all GIS failures are due to poor current carrying contacts in GIS. The Israel Electric Company (IEC) in seeking a solution to this problem have undertaken experimental work to examine the possibility of in-service diagnostic of poor contact problem in GIS via direct local heating detection, using a Thermal Imaging System. The experiments were carried out on the part of the GIS with nominal SF6 pressure. The following aspects of the problem were examined: - the range of power released in the defective contact that could give the practical temperature rise on the surface of enclosure; - temperature distribution on the surface of enclosure; - the influence of spacer type (with holes or without) on the heat transfer process; - the influence of the length of SF6 tubes and there position (horizontal or vertical); - the temperature difference between upper and lower parts of the tubes in horizontal position; - practical use of the Thermal Imaging System for detecting poor contact problem in GIS.

A Novel Algorithm Combining Finite State Method and Genetic Algorithm for Solving Crude Oil Scheduling Problem

PubMed Central

Duan, Qian-Qian; Yang, Gen-Ke; Pan, Chang-Chun

2014-01-01

A hybrid optimization algorithm combining finite state method (FSM) and genetic algorithm (GA) is proposed to solve the crude oil scheduling problem. The FSM and GA are combined to take the advantage of each method and compensate deficiencies of individual methods. In the proposed algorithm, the finite state method makes up for the weakness of GA which is poor at local searching ability. The heuristic returned by the FSM can guide the GA algorithm towards good solutions. The idea behind this is that we can generate promising substructure or partial solution by using FSM. Furthermore, the FSM can guarantee that the entire solution space is uniformly covered. Therefore, the combination of the two algorithms has better global performance than the existing GA or FSM which is operated individually. Finally, a real-life crude oil scheduling problem from the literature is used for conducting simulation. The experimental results validate that the proposed method outperforms the state-of-art GA method. PMID:24772031

The Hybrid Management Model: Influences of Organizational Structure and IT Project Management Practices on the Performance of Federal IT Projects

ERIC Educational Resources Information Center

Neves, Celine A.

2012-01-01

The federal government spends much money on information technology (IT) projects each year, yet numerous IT projects continue to underperform. For instance, in Fiscal Year 2008, OMB and federal agencies identified approximately 413 IT projects ($25.2 billion) as being poorly planned, poorly performing, or both. Agencies struggle to implement sound…

Eye-Movement Patterns and Reader Characteristics of Students with Good and Poor Performance When Reading Scientific Text with Diagrams

ERIC Educational Resources Information Center

Jian, Yu-Cin

2017-01-01

This study investigated the cognitive processes and reader characteristics of sixth graders who had good and poor performance when reading scientific text with diagrams. We first measured the reading ability and reading self-efficacy of sixth-grade participants, and then recorded their eye movements while they were reading an illustrated…

Improving the Instructional Leadership of Heads of Department in Under-Resourced Schools: A Collaborative Action-Learning Approach

ERIC Educational Resources Information Center

Seobi, Boitshepo Audrey; Wood, Lesley

2016-01-01

An unacceptable number of learners in under-resourced schools in South Africa are failing to perform adequately in national and international benchmark tests. Poor learner performance has been linked to poor-quality teaching, which, in turn, can be attributed in part to a lack of instructional leadership at schools. According to policy, heads of…

Assessment of muscle tissue oxygen saturation after out-of-hospital cardiac arrest.

PubMed

Orban, Jean-Christophe; Scarlatti, Audrey; Danin, Pierre-Eric; Dellamonica, Jean; Bernardin, Gilles; Ichai, Carole

2015-12-01

Pathophysiology of cardiac arrest corresponds to an ischemia-reperfusion syndrome with deep impairment of microcirculation. Muscular tissue oxygen saturation (StO2) is a noninvasive method of evaluation of microcirculation. Our study was aimed at assessing the prognosis value of muscular StO2 in patients admitted for out-of-hospital cardiac arrest (OHCA) and treated with hypothermia. We conducted a prospective bicentric observational study including OHCA patients treated with therapeutic hypothermia. Baseline StO2, derived variables (desaturation and resaturation slopes), and lactate levels were compared at different times between patients with good and poor outcomes. Prognosis was assessed by the Cerebral Performance Category (CPC) score at 6 months after admission (CPC 1-2, good outcome; CPC 3-5, poor outcome). Forty-four patients were included, 17 good and 27 poor outcomes at 6 months. At admission, StO2 and lactate levels were lower in good outcome patients. Desaturation and resaturation slopes did not differ between groups. After an OHCA treated with therapeutic hypothermia, StO2 was correlated with outcome. Further research is needed to better understand the pathophysiological process underlying our results. Copyright © 2015 Elsevier Inc. All rights reserved.

Development and application of bio-sample quantification to evaluate stability and pharmacokinetics of inulin-type fructo-oligosaccharides from Morinda Officinalis.

PubMed

Chi, Liandi; Chen, Lingxiao; Zhang, Jiwen; Zhao, Jing; Li, Shaoping; Zheng, Ying

2018-07-15

Inulin-type fructooligosaccharides (FOS) purified from Morinda Officinalis, with degrees of polymerization (DP) from 3 to 9, have been approved in China as an oral prescribed drug for mild and moderate depression episode, while the stability and oral absorption of this FOS mixtures are largely unknown. As the main active component and quality control marker for above FOS, DP5 was selected as the representative FOS in this study. Desalting method by ion exchange resin was developed to treat bio-sample, followed by separation and quantification by high performance liquid chromatography-charged aerosol detector. Results showed that the DP5 was stepwisely hydrolyzed in simulated gastric fluid and gut microbiota, while maintained stable in intestinal fluid. DP5 has poor permeability across Caco-2 monolayer with P app of 5.22 × 10 -7  cm/s, and very poor oral absorption with bioavailability of (0.50 ± 0.12)% in rat. In conclusion, FOS in Morinda Officinalis demonstrated poor chemical stability in simulated gastric fluid and human gut microbiota, and low oral absorption in rats. Copyright © 2018 Elsevier B.V. All rights reserved.

Reason behind wet pack after steam sterilization and its consequences: An overview from Central Sterile Supply Department of a cancer center in eastern India.

PubMed

Basu, Debabrata

Wet pack after steam sterilization process that means there are surely obtain millions of microorganisms that can breed and multiply rapidly and objects are unsterile and can never be used for further procedure. There are many reasons behind the wet pack occurrences after autoclaving like poor quality of wrapping materials, faulty valves of rigid container, faulty loading and packaging technique, poor steam quality, sterilizer malfunction and may be design related problems in CSSD sterile storage area. Cause of wet pack after steam sterilization processes may occur severe problems because of wasted time and effort, increased work load, increased cost, potentially contaminated instruments, infection risk to the patient, poor patient outcomes and delayed or cancellation of procedures. But such wet pack scenario can be avoided by various methods by using good steam (water) quality, performing periodic maintenance of the Autoclaves, avoidance of sterilizer overloading, allowing adequate post sterilization time to cool down the materials to room temperature, using good quality wrapping materials, properly maintain temperature and humidity of sterile storage area etc. Copyright © 2016 King Saud Bin Abdulaziz University for Health Sciences. Published by Elsevier Ltd. All rights reserved.

Developing Appropriate Methods for Cost-Effectiveness Analysis of Cluster Randomized Trials

PubMed Central

Gomes, Manuel; Ng, Edmond S.-W.; Nixon, Richard; Carpenter, James; Thompson, Simon G.

2012-01-01

Aim. Cost-effectiveness analyses (CEAs) may use data from cluster randomized trials (CRTs), where the unit of randomization is the cluster, not the individual. However, most studies use analytical methods that ignore clustering. This article compares alternative statistical methods for accommodating clustering in CEAs of CRTs. Methods. Our simulation study compared the performance of statistical methods for CEAs of CRTs with 2 treatment arms. The study considered a method that ignored clustering—seemingly unrelated regression (SUR) without a robust standard error (SE)—and 4 methods that recognized clustering—SUR and generalized estimating equations (GEEs), both with robust SE, a “2-stage” nonparametric bootstrap (TSB) with shrinkage correction, and a multilevel model (MLM). The base case assumed CRTs with moderate numbers of balanced clusters (20 per arm) and normally distributed costs. Other scenarios included CRTs with few clusters, imbalanced cluster sizes, and skewed costs. Performance was reported as bias, root mean squared error (rMSE), and confidence interval (CI) coverage for estimating incremental net benefits (INBs). We also compared the methods in a case study. Results. Each method reported low levels of bias. Without the robust SE, SUR gave poor CI coverage (base case: 0.89 v. nominal level: 0.95). The MLM and TSB performed well in each scenario (CI coverage, 0.92–0.95). With few clusters, the GEE and SUR (with robust SE) had coverage below 0.90. In the case study, the mean INBs were similar across all methods, but ignoring clustering underestimated statistical uncertainty and the value of further research. Conclusions. MLMs and the TSB are appropriate analytical methods for CEAs of CRTs with the characteristics described. SUR and GEE are not recommended for studies with few clusters. PMID:22016450

The Associations Between Clerkship Objective Structured Clinical Examination (OSCE) Grades and Subsequent Performance.

PubMed

Dong, Ting; Zahn, Christopher; Saguil, Aaron; Swygert, Kimberly A; Yoon, Michelle; Servey, Jessica; Durning, Steven

2017-01-01

Construct: We investigated the extent of the associations between medical students' clinical competency measured by performance in Objective Structured Clinical Examinations (OSCE) during Obstetrics/Gynecology and Family Medicine clerkships and later performance in both undergraduate and graduate medical education. There is a relative dearth of studies on the correlations between undergraduate OSCE scores and future exam performance within either undergraduate or graduate medical education and almost none on linking these simulated encounters to eventual patient care. Of the research studies that do correlate clerkship OSCE scores with future performance, these often have a small sample size and/or include only 1 clerkship. Students in USU graduating classes of 2007 through 2011 participated in the study. We investigated correlations between clerkship OSCE grades with United States Medical Licensing Examination Step 2 Clinical Knowledge, Clinical Skills, and Step 3 Exams scores as well as Postgraduate Year 1 program director's evaluation scores on Medical Expertise and Professionalism. We also conducted contingency table analysis to examine the associations between poor performance on clerkship OSCEs with failing Step 3 and receiving poor program director ratings. The correlation coefficients were weak between the clerkship OSCE grades and the outcomes. The strongest correlations existed between the clerkship OSCE grades and the Step 2 CS Integrated Clinical Encounter component score, Step 2 Clinical Skills, and Step 3 scores. Contingency table associations between poor performances on both clerkships OSCEs and poor Postgraduate Year 1 Program Director ratings were significant. The results of this study provide additional but limited validity evidence for the use of OSCEs during clinical clerkships given their associations with subsequent performance measures.

Cholinergic control over attention in rats prone to attribute incentive salience to reward cues

PubMed Central

Paolone, Giovanna; Angelakos, Christopher C.; Meyer, Paul J.; Robinson, Terry E.; Sarter, Martin

2013-01-01

Some rats (sign-trackers, ST) are especially prone to attribute incentive salience to reward cues, relative to others (goal-trackers, GT). Thus, reward cues are more likely to promote maladaptive reward-seeking behavior in ST than GT. Here, we asked whether ST and GT differ on another trait that can contribute to poor restraint over behavior evoked by reward cues. We report that, relative to GT, ST have poor control over attentional performance, due in part to insufficient cholinergic stimulation of cortical circuitry. We found that, relative to GT, ST showed poor performance on a sustained attention task (SAT). Furthermore, their performance fluctuated rapidly between periods of good to near-chance performance. This finding was reproduced using a separate cohort of rats. As demonstrated earlier, performance on the SAT was associated with increases in extracellular levels of cortical acetylcholine (ACh); however, SAT performance-associated increases in ACh levels were significantly attenuated in ST relative to GT. Consistent with the view that the modulatory effects of ACh involves stimulation of α4β2* nicotinic acetylcholine receptors (nAChRs), systemic administration of the partial nAChR agonist ABT-089 improved SAT performance in ST and abolished the difference between SAT-associated ACh levels in ST and GT. Neither the nonselective nAChR agonist nicotine nor the psychostimulant amphetamine improved SAT performance. These findings suggest that individuals who have a propensity to attribute high incentive salience to reward cues also exhibit relatively poor attentional control. A combination of these traits may render individuals especially vulnerable to disorders such as obesity and addiction. PMID:23658172

Quantification of the fraction poorly deformable red blood cells using ektacytometry.

PubMed

Streekstra, G J; Dobbe, J G G; Hoekstra, A G

2010-06-21

We describe a method to obtain the fraction of poorly deformable red blood cells in a blood sample from the intensity pattern in an ektacytometer. In an ektacytometer red blood cells are transformed into ellipsoids by a shear flow between two transparent cylinders. The intensity pattern, due to a laser beam that is sent through the suspension, is projected on a screen. When measuring a healthy red blood cell population iso-intensity curves are ellipses with an axial ratio equal to that of the average red blood cell. In contrast poorly deformable cells result in circular iso-intensity curves. In this study we show that for mixtures of deformable and poorly deformable red blood cells, iso-intensity curves in the composite intensity pattern are neither elliptical nor circular but obtain cross-like shapes. We propose a method to obtain the fraction of poorly deformable red blood cells from those intensity patterns. Experiments with mixtures of poorly deformable and deformable red blood cells validate the method and demonstrate its accuracy. In a clinical setting our approach is potentially of great value for the detection of the fraction of sickle cells in blood samples of patients with sickle cell disease or to find a measure for the parasitemia in patients infected with malaria.

Conducting effective performance appraisals.

PubMed

2001-01-01

According to experts, performance appraisals rate just below firing someone as the least favorite thing managers do. Many factors contribute to this view--one is that current systems do a poor job of evaluating performance and in fact often impede both evaluation and performance. When used as part of an ongoing supportive process of goal setting and feedback, performance appraisals can enhance performance and morale. One alternative to traditional employee evaluation methods is full-circle or 360-degree feedback. Contained in this issue are practical suggestions for preparing employees for performance appraisals which, when followed daily, encourage employees to put their best feet forward as part of their regular routine. Also included is a template specific to assessing the performance of clinical laboratory technologists . Additionally, numerous resources are provided to help you refine appraisal systems to fit your needs. Full-circle feedback is proving to be a boon to managers. It relieves them from being the exclusive "heavies" in evaluating performance, integrates appraisal input from several sources, and incorporates increasing employee skills, competencies, and satisfaction, thus improving productivity of people and processes. And aren't integration and continuous improvement what the laboratory is all about?

Three methods to monitor utilization of healthcare services by the poor

PubMed Central

Bhuiya, Abbas; Hanifi, SMA; Urni, Farhana; Mahmood, Shehrin Shaila

2009-01-01

Background Achieving equity by way of improving the condition of the economically poor or otherwise disadvantaged is among the core goals of contemporary development paradigm. This places importance on monitoring outcome indicators among the poor. National surveys allow disaggregation of outcomes by socioeconomic status at national level and do not have statistical adequacy to provide estimates for lower level administrative units. This limits the utility of these data for programme managers to know how well particular services are reaching the poor at the lowest level. Managers are thus left without a tool for monitoring results for the poor at lower levels. This paper demonstrates that with some extra efforts community and facility based data at the lower level can be used to monitor utilization of healthcare services by the poor. Methods Data used in this paper came from two sources- Chakaria Health and Demographic Surveillance System (HDSS) of ICDDR,B and from a special study conducted during 2006 among patients attending the public and private health facilities in Chakaria, Bangladesh. The outcome variables included use of skilled attendants for delivery and use of facilities. Rate-ratio, rate-difference, concentration index, benefit incidence ratio, sequential sampling, and Lot Quality Assurance Sampling were used to assess how pro-poor is the use of skilled attendants for delivery and healthcare facilities. Findings Poor are using skilled attendants for delivery far less than the better offs. Government health service facilities are used more than the private facilities by the poor. Benefit incidence analysis and sequential sampling techniques could assess the situation realistically which can be used for monitoring utilization of services by poor. The visual display of the findings makes both these methods attractive. LQAS, on the other hand, requires small fixed sample and always enables decision making. Conclusion With some extra efforts monitoring of the utilization of healthcare services by the poor at the facilities can be done reliably. If monitored, the findings can guide the programme and facility managers to act in a timely fashion to improve the effectiveness of the programme in reaching the poor. PMID:19650938

What predicts performance during clinical psychology training?

PubMed Central

Scior, Katrina; Bradley, Caroline E; Potts, Henry W W; Woolf, Katherine; de C Williams, Amanda C

2014-01-01

Objectives While the question of who is likely to be selected for clinical psychology training has been studied, evidence on performance during training is scant. This study explored data from seven consecutive intakes of the UK's largest clinical psychology training course, aiming to identify what factors predict better or poorer outcomes. Design Longitudinal cross-sectional study using prospective and retrospective data. Method Characteristics at application were analysed in relation to a range of in-course assessments for 274 trainee clinical psychologists who had completed or were in the final stage of their training. Results Trainees were diverse in age, pre-training experience, and academic performance at A-level (advanced level certificate required for university admission), but not in gender or ethnicity. Failure rates across the three performance domains (academic, clinical, research) were very low, suggesting that selection was successful in screening out less suitable candidates. Key predictors of good performance on the course were better A-levels and better degree class. Non-white students performed less well on two outcomes. Type and extent of pre-training clinical experience on outcomes had varied effects on outcome. Research supervisor ratings emerged as global indicators and predicted nearly all outcomes, but may have been biased as they were retrospective. Referee ratings predicted only one of the seven outcomes examined, and interview ratings predicted none of the outcomes. Conclusions Predicting who will do well or poorly in clinical psychology training is complex. Interview and referee ratings may well be successful in screening out unsuitable candidates, but appear to be a poor guide to performance on the course. Practitioner points While referee and selection interview ratings did not predict performance during training, they may be useful in screening out unsuitable candidates at the application stage High school final academic performance was the best predictor of good performance during clinical psychology training The findings are derived from seven cohorts of one training course, the UK's largest; they cannot be assumed to generalize to all training courses PMID:24206117

Reading comprehension and expressive writing: a comparison between good and poor comprehenders.

PubMed

Carretti, Barbara; Re, Anna Maria; Arfè, Barbara

2013-01-01

This study investigated expressive writing in 8- to 10-year-old children with different levels of reading comprehension. Poor and good comprehenders were presented with three expressive writing tasks where the modality (pictorial vs. verbal) and the text genre (narrative vs. descriptive) varied. Results showed that poor comprehenders' performance was minimally influenced by the modality of the prompt. In fact, their performance was generally worse than that of good comprehenders and affected by the text genre, as the quality of their narratives was generally lower than that of good comprehenders. However, in the descriptive text condition, their performance was comparable to that of good comprehenders. One can conclude that their problems depend on the characteristics of the narrative text where coherence and causality are important elements.

The association between teenage motherhood and poor offspring outcomes: A national cohort study across 30 years

PubMed Central

Coyne, Claire A; Långström, Niklas; Rickert, Martin E; Lichtenstein, Paul; D’Onofrio, Brian M

2013-01-01

Teenage motherhood is associated with poor offspring outcomes but these associations may be influenced by offspring birth year because of substantial social changes in recent decades. Existing research also has not examined whether these associations are due to the specific effect of mother’s age at childbirth or factors shared by siblings in a family. We used a population-based cohort study in Sweden comprising all children born from 1960–1989 (N=3,162,239), and a subsample of siblings differentially exposed to maternal teenage childbearing (N=485,259) to address these limitations. We examined the effect of teenage childbearing on offspring violent and nonviolent criminal convictions, poor academic performance, and substance-related problems. Population-wide, teenage childbearing was associated with offspring criminal convictions, poor academic performance, and substance-related problems. The magnitude of these associations increased over time. Comparisons of differentially exposed siblings indicated no within-family association between teenage childbearing and offspring violent and nonviolent criminal convictions or poor academic performance, although offspring born to teenage mothers were more likely to experience substance-related problems than their later-born siblings. Being born to a teenage mother in Sweden has become increasingly associated with negative outcomes across time, but the nature of this association may differ by outcome. Teenage childbearing may be associated with offspring violent and nonviolent criminal convictions and poor academic performance because of shared familial risk factors but may be causally associated with offspring substance-related problems. The findings suggest that interventions to improve offspring outcomes should delay teenage childbearing and target risk factors influencing all offspring of teenage mothers. PMID:23632141

Impact of poor oral health on children's school attendance and performance.

PubMed

Jackson, Stephanie L; Vann, William F; Kotch, Jonathan B; Pahel, Bhavna T; Lee, Jessica Y

2011-10-01

We examined school days missed for routine dental care versus dental pain or infection to determine the relationship between children's oral health status and school attendance and performance. We used 2008 data from the North Carolina Child Health Assessment and Monitoring Program. The study sample, weighted to reflect the state's population, included 2183 schoolchildren. Variables assessed included school absences and performance, oral health status, parental education, health insurance coverage, race, and gender. Children with poor oral health status were nearly 3 times more likely (odds ratio = 3.89; 95% confidence interval = 1.96, 7.75) than were their counterparts to miss school as a result of dental pain. Absences caused by pain were associated with poorer school performance (P < .05), but absences for routine care were not. Mediation analyses revealed that oral health status was associated with performance independent of absence for pain. Children with poorer oral health status were more likely to experience dental pain, miss school, and perform poorly in school. These findings suggest that improving children's oral health status may be a vehicle to enhancing their educational experience.