Funding Medical Research Projects: Taking into Account Referees' Severity and Consistency through Many-Faceted Rasch Modeling of Projects' Scores.

Science.gov (United States)

Tesio, Luigi; Simone, Anna; Grzeda, Mariuzs T; Ponzio, Michela; Dati, Gabriele; Zaratin, Paola; Perucca, Laura; Battaglia, Mario A

2015-01-01

The funding policy of research projects often relies on scores assigned by a panel of experts (referees). The non-linear nature of raw scores and the severity and inconsistency of individual raters may generate unfair numeric project rankings. Rasch measurement (many-facets version, MFRM) provides a valid alternative to scoring. MFRM was applied to the scores achieved by 75 research projects on multiple sclerosis sent in response to a previous annual call by FISM-Italian Foundation for Multiple Sclerosis. This allowed to simulate, a posteriori, the impact of MFRM on the funding scenario. The applications were each scored by 2 to 4 independent referees (total = 131) on a 10-item, 0-3 rating scale called FISM-ProQual-P. The rotation plan assured "connection" of all pairs of projects through at least 1 shared referee.The questionnaire fulfilled satisfactorily the stringent criteria of Rasch measurement for psychometric quality (unidimensionality, reliability and data-model fit). Arbitrarily, 2 acceptability thresholds were set at a raw score of 21/30 and at the equivalent Rasch measure of 61.5/100, respectively. When the cut-off was switched from score to measure 8 out of 18 acceptable projects had to be rejected, while 15 rejected projects became eligible for funding. Some referees, of various severity, were grossly inconsistent (z-std fit indexes less than -1.9 or greater than 1.9). The FISM-ProQual-P questionnaire seems a valid and reliable scale. MFRM may help the decision-making process for allocating funds to MS research projects but also in other fields. In repeated assessment exercises it can help the selection of reliable referees. Their severity can be steadily calibrated, thus obviating the need to connect them with other referees assessing the same projects.

Sample Size and Statistical Conclusions from Tests of Fit to the Rasch Model According to the Rasch Unidimensional Measurement Model (Rumm) Program in Health Outcome Measurement.

Science.gov (United States)

Hagell, Peter; Westergren, Albert

Sample size is a major factor in statistical null hypothesis testing, which is the basis for many approaches to testing Rasch model fit. Few sample size recommendations for testing fit to the Rasch model concern the Rasch Unidimensional Measurement Models (RUMM) software, which features chi-square and ANOVA/F-ratio based fit statistics, including Bonferroni and algebraic sample size adjustments. This paper explores the occurrence of Type I errors with RUMM fit statistics, and the effects of algebraic sample size adjustments. Data with simulated Rasch model fitting 25-item dichotomous scales and sample sizes ranging from N = 50 to N = 2500 were analysed with and without algebraically adjusted sample sizes. Results suggest the occurrence of Type I errors with N less then or equal to 500, and that Bonferroni correction as well as downward algebraic sample size adjustment are useful to avoid such errors, whereas upward adjustment of smaller samples falsely signal misfit. Our observations suggest that sample sizes around N = 250 to N = 500 may provide a good balance for the statistical interpretation of the RUMM fit statistics studied here with respect to Type I errors and under the assumption of Rasch model fit within the examined frame of reference (i.e., about 25 item parameters well targeted to the sample).

Rasch analysis of the Multiple Sclerosis Impact Scale (MSIS-29

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Misajon Rose

2009-06-01

Full Text Available Abstract Background Multiple Sclerosis (MS is a degenerative neurological disease that causes impairments, including spasticity, pain, fatigue, and bladder dysfunction, which negatively impact on quality of life. The Multiple Sclerosis Impact Scale (MSIS-29 is a disease-specific health-related quality of life (HRQoL instrument, developed using the patient's perspective on disease impact. It consists of two subscales assessing the physical (MSIS-29-PHYS and psychological (MSIS-29-PSYCH impact of MS. Although previous studies have found support for the psychometric properties of the MSIS-29 using traditional methods of scale evaluation, the scale has not been subjected to a detailed Rasch analysis. Therefore, the objective of this study was to use Rasch analysis to assess the internal validity of the scale, and its response format, item fit, targeting, internal consistency and dimensionality. Methods Ninety-two persons with definite MS residing in the community were recruited from a tertiary hospital database. Patients completed the MSIS-29 as part of a larger study. Rasch analysis was undertaken to assess the psychometric properties of the MSIS-29. Results Rasch analysis showed overall support for the psychometric properties of the two MSIS-29 subscales, however it was necessary to reduce the response format of the MSIS-29-PHYS to a 3-point response scale. Both subscales were unidimensional, had good internal consistency, and were free from item bias for sex and age. Dimensionality testing indicated it was not appropriate to combine the two subscales to form a total MSIS score. Conclusion In this first study to use Rasch analysis to fully assess the psychometric properties of the MSIS-29 support was found for the two subscales but not for the use of the total scale. Further use of Rasch analysis on the MSIS-29 in larger and broader samples is recommended to confirm these findings.

Rasch analysis of the Multiple Sclerosis Impact Scale (MSIS-29)

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Ramp, Melina; Khan, Fary; Misajon, Rose Anne; Pallant, Julie F

2009-01-01

Background Multiple Sclerosis (MS) is a degenerative neurological disease that causes impairments, including spasticity, pain, fatigue, and bladder dysfunction, which negatively impact on quality of life. The Multiple Sclerosis Impact Scale (MSIS-29) is a disease-specific health-related quality of life (HRQoL) instrument, developed using the patient's perspective on disease impact. It consists of two subscales assessing the physical (MSIS-29-PHYS) and psychological (MSIS-29-PSYCH) impact of MS. Although previous studies have found support for the psychometric properties of the MSIS-29 using traditional methods of scale evaluation, the scale has not been subjected to a detailed Rasch analysis. Therefore, the objective of this study was to use Rasch analysis to assess the internal validity of the scale, and its response format, item fit, targeting, internal consistency and dimensionality. Methods Ninety-two persons with definite MS residing in the community were recruited from a tertiary hospital database. Patients completed the MSIS-29 as part of a larger study. Rasch analysis was undertaken to assess the psychometric properties of the MSIS-29. Results Rasch analysis showed overall support for the psychometric properties of the two MSIS-29 subscales, however it was necessary to reduce the response format of the MSIS-29-PHYS to a 3-point response scale. Both subscales were unidimensional, had good internal consistency, and were free from item bias for sex and age. Dimensionality testing indicated it was not appropriate to combine the two subscales to form a total MSIS score. Conclusion In this first study to use Rasch analysis to fully assess the psychometric properties of the MSIS-29 support was found for the two subscales but not for the use of the total scale. Further use of Rasch analysis on the MSIS-29 in larger and broader samples is recommended to confirm these findings. PMID:19545445

Rasch Analysis of the Locus-of-Hope Scale. Brief Report

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Gadiana, Leny G.; David, Adonis P.

2015-01-01

The Locus-of-Hope Scale (LHS) was developed as a measure of the locus-of-hope dimensions (Bernardo, 2010). The present study adds to the emerging literature on locus-of-hope by assessing the psychometric properties of the LHS using Rasch analysis. The results from the Rasch analyses of the four subscales of LHS provided evidence on the…

Improving the Individual Work Performance Questionnaire using Rasch analysis.

OpenAIRE

Koopmans, L.; Bernaards, C.M.; Hildebrandt, V.H.; Buuren, S. van; Beek, A.J. van der; Vet, H.C.W. de

2014-01-01

Recently, the Individual Work Performance Questionnaire (IWPQ) version 0.2 was developed using Rasch analysis. The goal of the current study was to improve targeting of the IWPQ scales by including additional items. The IWPQ 0.2 (original) and 0.3 (including additional items) were examined using Rasch analysis. Additional items that showed misfit or did not improve targeting were removed from the IWPQ 0.3, resulting in a final IWPQ 1.0. Subsequently, the scales showed good model fit and relia...

Detecting Aberrant Response Patterns in the Rasch Model. Rapport 87-3.

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Kogut, Jan

In this paper, the detection of response patterns aberrant from the Rasch model is considered. For this purpose, a new person fit index, recently developed by I. W. Molenaar (1987) and an iterative estimation procedure are used in a simulation study of Rasch model data mixed with aberrant data. Three kinds of aberrant response behavior are…

Guessing and the Rasch Model

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Holster, Trevor A.; Lake, J.

2016-01-01

Stewart questioned Beglar's use of Rasch analysis of the Vocabulary Size Test (VST) and advocated the use of 3-parameter logistic item response theory (3PLIRT) on the basis that it models a non-zero lower asymptote for items, often called a "guessing" parameter. In support of this theory, Stewart presented fit statistics derived from…

Item Information in the Rasch Model

NARCIS (Netherlands)

Engelen, Ron J.H.; van der Linden, Willem J.; Oosterloo, Sebe J.

1988-01-01

Fisher's information measure for the item difficulty parameter in the Rasch model and its marginal and conditional formulations are investigated. It is shown that expected item information in the unconditional model equals information in the marginal model, provided the assumption of sampling

Examination of a Social-Networking Site Activities Scale (SNSAS) Using Rasch Analysis

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Alhaythami, Hassan; Karpinski, Aryn; Kirschner, Paul; Bolden, Edward

2017-01-01

This study examined the psychometric properties of a social-networking site (SNS) activities scale (SNSAS) using Rasch Analysis. Items were also examined with Rasch Principal Components Analysis (PCA) and Differential Item Functioning (DIF) across groups of university students (i.e., males and females from the United States [US] and Europe; N =…

Construct validity of the Heart Failure Screening Tool (Heart-FaST) to identify heart failure patients at risk of poor self-care: Rasch analysis.

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Reynolds, Nicholas A; Ski, Chantal F; McEvedy, Samantha M; Thompson, David R; Cameron, Jan

2018-02-14

The aim of this study was to psychometrically evaluate the Heart Failure Screening Tool (Heart-FaST) via: (1) examination of internal construct validity; (2) testing of scale function in accordance with design; and (3) recommendation for change/s, if items are not well adjusted, to improve psychometric credential. Self-care is vital to the management of heart failure. The Heart-FaST may provide a prospective assessment of risk, regarding the likelihood that patients with heart failure will engage in self-care. Psychometric validation of the Heart-FaST using Rasch analysis. The Heart-FaST was administered to 135 patients (median age = 68, IQR = 59-78 years; 105 males) enrolled in a multidisciplinary heart failure management program. The Heart-FaST is a nurse-administered tool for screening patients with HF at risk of poor self-care. A Rasch analysis of responses was conducted which tested data against Rasch model expectations, including whether items serve as unbiased, non-redundant indicators of risk and measure a single construct and that rating scales operate as intended. The results showed that data met Rasch model expectations after rescoring or deleting items due to poor discrimination, disordered thresholds, differential item functioning, or response dependence. There was no evidence of multidimensionality which supports the use of total scores from Heart-FaST as indicators of risk. Aggregate scores from this modified screening tool rank heart failure patients according to their "risk of poor self-care" demonstrating that the Heart-FaST items constitute a meaningful scale to identify heart failure patients at risk of poor engagement in heart failure self-care. © 2018 John Wiley & Sons Ltd.

Rasch model analysis of the Depression, Anxiety and Stress Scales (DASS).

Science.gov (United States)

Shea, Tracey L; Tennant, Alan; Pallant, Julie F

2009-05-09

There is a growing awareness of the need for easily administered, psychometrically sound screening tools to identify individuals with elevated levels of psychological distress. Although support has been found for the psychometric properties of the Depression, Anxiety and Stress Scales (DASS) using classical test theory approaches it has not been subjected to Rasch analysis. The aim of this study was to use Rasch analysis to assess the psychometric properties of the DASS-21 scales, using two different administration modes. The DASS-21 was administered to 420 participants with half the sample responding to a web-based version and the other half completing a traditional pencil-and-paper version. Conformity of DASS-21 scales to a Rasch partial credit model was assessed using the RUMM2020 software. To achieve adequate model fit it was necessary to remove one item from each of the DASS-21 subscales. The reduced scales showed adequate internal consistency reliability, unidimensionality and freedom from differential item functioning for sex, age and mode of administration. Analysis of all DASS-21 items combined did not support its use as a measure of general psychological distress. A scale combining the anxiety and stress items showed satisfactory fit to the Rasch model after removal of three items. The results provide support for the measurement properties, internal consistency reliability, and unidimensionality of three slightly modified DASS-21 scales, across two different administration methods. The further use of Rasch analysis on the DASS-21 in larger and broader samples is recommended to confirm the findings of the current study.

Rasch model analysis of the Depression, Anxiety and Stress Scales (DASS)

Science.gov (United States)

Shea, Tracey L; Tennant, Alan; Pallant, Julie F

2009-01-01

Background There is a growing awareness of the need for easily administered, psychometrically sound screening tools to identify individuals with elevated levels of psychological distress. Although support has been found for the psychometric properties of the Depression, Anxiety and Stress Scales (DASS) using classical test theory approaches it has not been subjected to Rasch analysis. The aim of this study was to use Rasch analysis to assess the psychometric properties of the DASS-21 scales, using two different administration modes. Methods The DASS-21 was administered to 420 participants with half the sample responding to a web-based version and the other half completing a traditional pencil-and-paper version. Conformity of DASS-21 scales to a Rasch partial credit model was assessed using the RUMM2020 software. Results To achieve adequate model fit it was necessary to remove one item from each of the DASS-21 subscales. The reduced scales showed adequate internal consistency reliability, unidimensionality and freedom from differential item functioning for sex, age and mode of administration. Analysis of all DASS-21 items combined did not support its use as a measure of general psychological distress. A scale combining the anxiety and stress items showed satisfactory fit to the Rasch model after removal of three items. Conclusion The results provide support for the measurement properties, internal consistency reliability, and unidimensionality of three slightly modified DASS-21 scales, across two different administration methods. The further use of Rasch analysis on the DASS-21 in larger and broader samples is recommended to confirm the findings of the current study. PMID:19426512

Reliability in the Rasch Model

Czech Academy of Sciences Publication Activity Database

Martinková, Patrícia; Zvára, K.

2007-01-01

Roč. 43, č. 3 (2007), s. 315-326 ISSN 0023-5954 R&D Projects: GA MŠk(CZ) 1M06014 Institutional research plan: CEZ:AV0Z10300504 Keywords : Cronbach's alpha * Rasch model * reliability Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.552, year: 2007 http://dml.cz/handle/10338.dmlcz/135776

Fitting polytomous Rasch models in SAS

DEFF Research Database (Denmark)

Christensen, Karl Bang

2006-01-01

The item parameters of a polytomous Rasch model can be estimated using marginal and conditional approaches. This paper describes how this can be done in SAS (V8.2) for three item parameter estimation procedures: marginal maximum likelihood estimation, conditional maximum likelihood estimation, an...

Measuring Mindfulness: A Rasch Analysis of the Freiburg Mindfulness Inventory

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Siobhan Lynch

2011-12-01

Full Text Available The objective of the study was to assess the psychometric properties of the Freiburg Mindfulness Inventory (FMI-14 using a Rasch model approach in a cross-sectional design. The scale was administered to N = 130 British patients with different psychosomatic conditions. The scale failed to show clear one-factoriality and item 13 did not fit the Rasch model. A two-factorial solution without item 13, however, appeared to fit well. The scale seemed to work equally well in different subgroups such as patients with or without mindfulness practice. However, some limitations of the validity of both the one-factorial and the two-factorial version of the scale were observed. Sizeable floor and ceiling effects limit the diagnostical use of the instrument. In summary, the study demonstrates that the two-factorial version of the FMI-13 shows acceptable approximation to Rasch requirements, but is in need of further improvement. The one-factorial solution did not fit well, and cannot be recommended for further use.

Rasch model analysis of the Depression, Anxiety and Stress Scales (DASS

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Tennant Alan

2009-05-01

Full Text Available Abstract Background There is a growing awareness of the need for easily administered, psychometrically sound screening tools to identify individuals with elevated levels of psychological distress. Although support has been found for the psychometric properties of the Depression, Anxiety and Stress Scales (DASS using classical test theory approaches it has not been subjected to Rasch analysis. The aim of this study was to use Rasch analysis to assess the psychometric properties of the DASS-21 scales, using two different administration modes. Methods The DASS-21 was administered to 420 participants with half the sample responding to a web-based version and the other half completing a traditional pencil-and-paper version. Conformity of DASS-21 scales to a Rasch partial credit model was assessed using the RUMM2020 software. Results To achieve adequate model fit it was necessary to remove one item from each of the DASS-21 subscales. The reduced scales showed adequate internal consistency reliability, unidimensionality and freedom from differential item functioning for sex, age and mode of administration. Analysis of all DASS-21 items combined did not support its use as a measure of general psychological distress. A scale combining the anxiety and stress items showed satisfactory fit to the Rasch model after removal of three items. Conclusion The results provide support for the measurement properties, internal consistency reliability, and unidimensionality of three slightly modified DASS-21 scales, across two different administration methods. The further use of Rasch analysis on the DASS-21 in larger and broader samples is recommended to confirm the findings of the current study.

USING RASCH ANALYSIS TO EXPLORE WHAT STUDENTS LEARN ABOUT PROBABILITY CONCEPTS

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Zamalia Mahmud

2015-01-01

Full Text Available Students’ understanding of probability concepts have been investigated from various different perspectives. This study was set out to investigate perceived understanding of probability concepts of forty-four students from the STAT131 Understanding Uncertainty and Variation course at the University of Wollongong, NSW. Rasch measurement which is based on a probabilistic model was used to identify concepts that students find easy, moderate and difficult to understand.  Data were captured from the e-learning Moodle platform where students provided their responses through an on-line quiz. As illustrated in the Rasch map, 96% of the students could understand about sample space, simple events, mutually exclusive events and tree diagram while 67% of the students found concepts of conditional and independent events rather easy to understand.Keywords: Perceived Understanding, Probability Concepts, Rasch Measurement Model DOI: dx.doi.org/10.22342/jme.61.1

Scale construction utilising the Rasch unidimensional measurement model: A measurement of adolescent attitudes towards abortion.

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Hendriks, Jacqueline; Fyfe, Sue; Styles, Irene; Skinner, S Rachel; Merriman, Gareth

2012-01-01

Measurement scales seeking to quantify latent traits like attitudes, are often developed using traditional psychometric approaches. Application of the Rasch unidimensional measurement model may complement or replace these techniques, as the model can be used to construct scales and check their psychometric properties. If data fit the model, then a scale with invariant measurement properties, including interval-level scores, will have been developed. This paper highlights the unique properties of the Rasch model. Items developed to measure adolescent attitudes towards abortion are used to exemplify the process. Ten attitude and intention items relating to abortion were answered by 406 adolescents aged 12 to 19 years, as part of the "Teen Relationships Study". The sampling framework captured a range of sexual and pregnancy experiences. Items were assessed for fit to the Rasch model including checks for Differential Item Functioning (DIF) by gender, sexual experience or pregnancy experience. Rasch analysis of the original dataset initially demonstrated that some items did not fit the model. Rescoring of one item (B5) and removal of another (L31) resulted in fit, as shown by a non-significant item-trait interaction total chi-square and a mean log residual fit statistic for items of -0.05 (SD=1.43). No DIF existed for the revised scale. However, items did not distinguish as well amongst persons with the most intense attitudes as they did for other persons. A person separation index of 0.82 indicated good reliability. Application of the Rasch model produced a valid and reliable scale measuring adolescent attitudes towards abortion, with stable measurement properties. The Rasch process provided an extensive range of diagnostic information concerning item and person fit, enabling changes to be made to scale items. This example shows the value of the Rasch model in developing scales for both social science and health disciplines.

Educational Leadership Effectiveness: A Rasch Analysis

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Sinnema, Claire; Ludlow, Larry; Robinson, Viviane

2016-01-01

Purpose: The purposes of this paper are, first, to establish the psychometric properties of the ELP tool, and, second, to test, using a Rasch item response theory analysis, the hypothesized progression of challenge presented by the items included in the tool. Design/ Methodology/ Approach: Data were collected at two time points through a survey of…

Validation of VARK learning modalities questionnaire using Rasch analysis

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Fitkov-Norris, E. D.; Yeghiazarian, A.

2015-02-01

This article discusses the application of Rasch analysis to assess the internal validity of a four sub-scale VARK (Visual, Auditory, Read/Write and Kinaesthetic) learning styles instrument. The results from the analysis show that the Rasch model fits the majority of the VARK questionnaire data and the sample data support the internal validity of the four sub-constructs at 1% level of significance for all but one item. While this suggests that the instrument could potentially be used as a predictor for a person's learning preference orientation, further analysis is necessary to confirm the invariability of the instrument across different user groups across factors such as gender, age, educational and cultural background.

A Comparison of Uniform DIF Effect Size Estimators under the MIMIC and Rasch Models

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Jin, Ying; Myers, Nicholas D.; Ahn, Soyeon; Penfield, Randall D.

2013-01-01

The Rasch model, a member of a larger group of models within item response theory, is widely used in empirical studies. Detection of uniform differential item functioning (DIF) within the Rasch model typically employs null hypothesis testing with a concomitant consideration of effect size (e.g., signed area [SA]). Parametric equivalence between…

The Rasch Poisson counts model for incomplete data : An application of the EM algorithm

NARCIS (Netherlands)

Jansen, G.G.H.

Rasch's Poisson counts model is a latent trait model for the situation in which K tests are administered to N examinees and the test score is a count [e.g., the repeated occurrence of some event, such as the number of items completed or the number of items answered (in)correctly]. The Rasch Poisson

Rasch-family models are more valuable than score-based approaches for analysing longitudinal patient-reported outcomes with missing data.

Science.gov (United States)

de Bock, Élodie; Hardouin, Jean-Benoit; Blanchin, Myriam; Le Neel, Tanguy; Kubis, Gildas; Bonnaud-Antignac, Angélique; Dantan, Étienne; Sébille, Véronique

2016-10-01

The objective was to compare classical test theory and Rasch-family models derived from item response theory for the analysis of longitudinal patient-reported outcomes data with possibly informative intermittent missing items. A simulation study was performed in order to assess and compare the performance of classical test theory and Rasch model in terms of bias, control of the type I error and power of the test of time effect. The type I error was controlled for classical test theory and Rasch model whether data were complete or some items were missing. Both methods were unbiased and displayed similar power with complete data. When items were missing, Rasch model remained unbiased and displayed higher power than classical test theory. Rasch model performed better than the classical test theory approach regarding the analysis of longitudinal patient-reported outcomes with possibly informative intermittent missing items mainly for power. This study highlights the interest of Rasch-based models in clinical research and epidemiology for the analysis of incomplete patient-reported outcomes data. © The Author(s) 2013.

A Rasch and factor analysis of the Functional Assessment of Cancer Therapy-General (FACT-G

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Selby Peter J

2007-04-01

Full Text Available Abstract Background Although the Functional Assessment of Cancer Therapy – General questionnaire (FACT-G has been validated few studies have explored the factor structure of the instrument, in particular using non-sample dependent measurement techniques, such as Rasch Models. Furthermore, few studies have explored the relationship between item fit to the Rasch Model and clinical utility. The aim of this study was to investigate the dimensionality and measurement properties of the FACT-G with Rasch Models and Factor analysis. Methods A factor analysis and Rasch analysis (Partial Credit Model was carried out on the FACT-G completed by a heterogeneous sample of cancer patients (n = 465. For the Rasch analysis item fit (infit mean squares ≥ 1.30, dimensionality and item invariance were assessed. The impact of removing misfitting items on the clinical utility of the subscales and FACT-G total scale was also assessed. Results The factor analysis demonstrated a four factor structure of the FACT-G which broadly corresponded to the four subscales of the instrument. Internal consistency for these four scales was very good (Cronbach's alpha 0.72 – 0.85. The Rasch analysis demonstrated that each of the subscales and the FACT-G total scale had misfitting items (infit means square ≥ 1.30. All these scales with the exception of the Social & Family Well-being Scale (SFWB were unidimensional. When misfitting items were removed, the effect sizes and the clinical utility of the instrument were maintained for the subscales and the total FACT-G scores. Conclusion The results of the traditional factor analysis and Rasch analysis of the FACT-G broadly agreed. Caution should be exercised when utilising the Social & Family Well-being scale and further work is required to determine whether this scale is best represented by two factors. Additionally, removing misfitting items from scales should be performed alongside an assessment of the impact on clinical utility.

Examining Teacher Grades Using Rasch Measurement Theory

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Randall, Jennifer; Engelhard, George, Jr.

2009-01-01

In this study, we present an approach to questionnaire design within educational research based on Guttman's mapping sentences and Many-Facet Rasch Measurement Theory. We designed a 54-item questionnaire using Guttman's mapping sentences to examine the grading practices of teachers. Each item in the questionnaire represented a unique student…

From Rasch scores to regression

DEFF Research Database (Denmark)

Christensen, Karl Bang

2006-01-01

Rasch models provide a framework for measurement and modelling latent variables. Having measured a latent variable in a population a comparison of groups will often be of interest. For this purpose the use of observed raw scores will often be inadequate because these lack interval scale propertie....... This paper compares two approaches to group comparison: linear regression models using estimated person locations as outcome variables and latent regression models based on the distribution of the score....

Measuring situational avoidance in older drivers: An application of Rasch analysis.

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Davis, Jessica; Conlon, Elizabeth; Ownsworth, Tamara; Morrissey, Shirley

2016-02-01

Situational avoidance is a form of driving self-regulation at the strategic level of driving behaviour. It has typically been defined as the purposeful avoidance of driving situations perceived as challenging or potentially hazardous. To date, assessment of the psychometric properties of existing scales that measure situational avoidance has been sparse. This study examined the contribution of Rasch analysis to the situational avoidance construct. Three hundred and ninety-nine Australian drivers (M=66.75, SD=10.14, range: 48-91 years) completed the Situational Avoidance Questionnaire (SAQ). Following removal of the item Parallel Parking, the scale conformed to a Rasch model, showing good person separation, sufficient reliability, little disordering of thresholds, and no evidence of differential item functioning by age or gender. The residuals were independent supporting the assumption of unidimensionality and in conforming to a Rasch model, SAQ items were found to be hierarchical or cumulative. Increased avoidance was associated with factors known to be related to driving self-regulation more broadly, including older age, female gender, reduced driving space and frequency, reporting a change in driving in the past five years and poorer indices of health (i.e., self-rated mood, vision and cognitive function). Overall, these results support the use of the SAQ as a psychometrically sound measure of situational avoidance. Application of Rasch analysis to this area of research advances understanding of the driving self-regulation construct and its practice by drivers in baby boomer and older adult generations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Analysis of letter name knowledge using Rasch measurement.

Science.gov (United States)

Bowles, Ryan P; Skibbe, Lori E; Justice, Laura M

2011-01-01

Letter name knowledge (LNK) is a key predictor of later reading ability and has been emphasized strongly in recent educational policy. Studies of LNK have implicitly treated it as a unidimensional construct with all letters equally relevant to its measurement. However, some empirical research suggests that contextual factors can affect the measurement of LNK. In this study, we analyze responses from 909 children on measures of LNK using the Rasch model and its extensions, and consider two contextual factors: the format of assessment and the own-name advantage, which states that children are more likely to know letters in their own first names. Results indicate that both contextual factors have important impacts on measurement and that LNK does not meet the requirements of Rasch measurement even when accounting for the contextual factors. These findings introduce philosophical concerns for measurement of constrained skills which have limited content for assessment.

Sample Size Determination for Rasch Model Tests

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Draxler, Clemens

2010-01-01

This paper is concerned with supplementing statistical tests for the Rasch model so that additionally to the probability of the error of the first kind (Type I probability) the probability of the error of the second kind (Type II probability) can be controlled at a predetermined level by basing the test on the appropriate number of observations.…

Exploring the measurement properties of the osteopathy clinical teaching questionnaire using Rasch analysis.

Science.gov (United States)

Vaughan, Brett

2018-01-01

Clinical teaching evaluations are common in health profession education programs to ensure students are receiving a quality clinical education experience. Questionnaires students use to evaluate their clinical teachers have been developed in professions such as medicine and nursing. The development of a questionnaire that is specifically for the osteopathy on-campus, student-led clinic environment is warranted. Previous work developed the 30-item Osteopathy Clinical Teaching Questionnaire. The current study utilised Rasch analysis to investigate the construct validity of the Osteopathy Clinical Teaching Questionnaire and provide evidence for the validity argument through fit to the Rasch model. Senior osteopathy students at four institutions in Australia, New Zealand and the United Kingdom rated their clinical teachers using the Osteopathy Clinical Teaching Questionnaire. Three hundred and ninety-nine valid responses were received and the data were evaluated for fit to the Rasch model. Reliability estimations (Cronbach's alpha and McDonald's omega) were also evaluated for the final model. The initial analysis demonstrated the data did not fit the Rasch model. Accordingly, modifications to the questionnaire were made including removing items, removing person responses, and rescoring one item. The final model contained 12 items and fit to the Rasch model was adequate. Support for unidimensionality was demonstrated through both the Principal Components Analysis/t-test, and the Cronbach's alpha and McDonald's omega reliability estimates. Analysis of the questionnaire using McDonald's omega hierarchical supported a general factor (quality of clinical teaching in osteopathy). The evidence for unidimensionality and the presence of a general factor support the calculation of a total score for the questionnaire as a sufficient statistic. Further work is now required to investigate the reliability of the 12-item Osteopathy Clinical Teaching Questionnaire to provide evidence

Circuitry linking the Csr and stringent response global regulatory systems.

Science.gov (United States)

Edwards, Adrianne N; Patterson-Fortin, Laura M; Vakulskas, Christopher A; Mercante, Jeffrey W; Potrykus, Katarzyna; Vinella, Daniel; Camacho, Martha I; Fields, Joshua A; Thompson, Stuart A; Georgellis, Dimitris; Cashel, Michael; Babitzke, Paul; Romeo, Tony

2011-06-01

CsrA protein regulates important cellular processes by binding to target mRNAs and altering their translation and/or stability. In Escherichia coli, CsrA binds to sRNAs, CsrB and CsrC, which sequester CsrA and antagonize its activity. Here, mRNAs for relA, spoT and dksA of the stringent response system were found among 721 different transcripts that copurified with CsrA. Many of the transcripts that copurified with CsrA were previously determined to respond to ppGpp and/or DksA. We examined multiple regulatory interactions between the Csr and stringent response systems. Most importantly, DksA and ppGpp robustly activated csrB/C transcription (10-fold), while they modestly activated csrA expression. We propose that CsrA-mediated regulation is relieved during the stringent response. Gel shift assays confirmed high affinity binding of CsrA to relA mRNA leader and weaker interactions with dksA and spoT. Reporter fusions, qRT-PCR and immunoblotting showed that CsrA repressed relA expression, and (p)ppGpp accumulation during stringent response was enhanced in a csrA mutant. CsrA had modest to negligible effects on dksA and spoT expression. Transcription of dksA was negatively autoregulated via a feedback loop that tended to mask CsrA effects. We propose that the Csr system fine-tunes the stringent response and discuss biological implications of the composite circuitry. © Published 2011. This article is a US Government work and is in the public domain in the USA.

Teachers' Checklist on Reading-Related Behavioral Characteristics of Chinese Primary Students: A Rasch Measurement Model Analysis

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Chan, David W.; Ho, Connie Suk-han; Chung, Kevin K. H.; Tsang, Suk-man; Lee, Suk-han

2010-01-01

Data of item responses to the Hong Kong Specific Learning Difficulties Behaviour Checklist from 673 Chinese primary grade students were analyzed using the dichotomous Rasch measurement model. Rasch scaling suggested that the data fit the model adequately with a latent dimension of global dyslexic dysfunctioning. Estimates of item attributes and…

Rasch-built Overall Disability Scale (R-ODS) for immune-mediated peripheral neuropathies.

Science.gov (United States)

van Nes, S I; Vanhoutte, E K; van Doorn, P A; Hermans, M; Bakkers, M; Kuitwaard, K; Faber, C G; Merkies, I S J

2011-01-25

To develop a patient-based, linearly weighted scale that captures activity and social participation limitations in patients with Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), and gammopathy-related polyneuropathy (MGUSP). A preliminary Rasch-built Overall Disability Scale (R-ODS) containing 146 activity and participation items was constructed, based on the WHO International Classification of Functioning, Disability and Health, literature search, and patient interviews. The preliminary R-ODS was assessed twice (interval: 2-4 weeks; test-retest reliability studies) in 294 patients who experienced GBS in the past (n = 174) or currently have stable CIDP (n = 80) or MGUSP (n = 40). Data were analyzed using the Rasch unidimensional measurement model (RUMM2020). The preliminary R-ODS did not meet the Rasch model expectations. Based on disordered thresholds, misfit statistics, item bias, and local dependency, items were systematically removed to improve the model fit, regularly controlling the class intervals and model statistics. Finally, we succeeded in constructing a 24-item scale that fulfilled all Rasch requirements. "Reading a newspaper/book" and "eating" were the 2 easiest items; "standing for hours" and "running" were the most difficult ones. Good validity and reliability were obtained. The R-ODS is a linearly weighted scale that specifically captures activity and social participation limitations in patients with GBS, CIDP, and MGUSP. Compared to the Overall Disability Sum Score, the R-ODS represents a wider range of item difficulties, thereby better targeting patients with different ability levels. If responsive, the R-ODS will be valuable for future clinical trials and follow-up studies in these conditions.

Rasch Analysis of Professional Behavior in Medical Education

Science.gov (United States)

Lange, R.; Verhulst, S. J.; Roberts, N. K.; Dorsey, J. K.

2015-01-01

The use of students' "consumer feedback" to assess faculty behavior and improve the process of medical education is a significant challenge. We used quantitative Rasch measurement to analyze pre-categorized student comments listed by 385 graduating medical students. We found that students differed little with respect to the number of…

A Cross-Cultural Validation of Stage Development: A Rasch Re-Analysis of Longitudinal Socio-Moral Reasoning Data

Science.gov (United States)

Boom, Jan; Wouters, Hans; Keller, Monika

2007-01-01

Kohlberg's characterization of moral development as displaying an invariant hierarchical order of structurally consistent stages is losing ground. However, by applying Rasch analysis, Dawson recently gave new interpretation and support to his characterization of stage development. Using Rasch models, we replicated and strengthened her findings in…

Comparison of CTT and Rasch-based approaches for the analysis of longitudinal Patient Reported Outcomes.

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Blanchin, Myriam; Hardouin, Jean-Benoit; Le Neel, Tanguy; Kubis, Gildas; Blanchard, Claire; Mirallié, Eric; Sébille, Véronique

2011-04-15

Health sciences frequently deal with Patient Reported Outcomes (PRO) data for the evaluation of concepts, in particular health-related quality of life, which cannot be directly measured and are often called latent variables. Two approaches are commonly used for the analysis of such data: Classical Test Theory (CTT) and Item Response Theory (IRT). Longitudinal data are often collected to analyze the evolution of an outcome over time. The most adequate strategy to analyze longitudinal latent variables, which can be either based on CTT or IRT models, remains to be identified. This strategy must take into account the latent characteristic of what PROs are intended to measure as well as the specificity of longitudinal designs. A simple and widely used IRT model is the Rasch model. The purpose of our study was to compare CTT and Rasch-based approaches to analyze longitudinal PRO data regarding type I error, power, and time effect estimation bias. Four methods were compared: the Score and Mixed models (SM) method based on the CTT approach, the Rasch and Mixed models (RM), the Plausible Values (PV), and the Longitudinal Rasch model (LRM) methods all based on the Rasch model. All methods have shown comparable results in terms of type I error, all close to 5 per cent. LRM and SM methods presented comparable power and unbiased time effect estimations, whereas RM and PV methods showed low power and biased time effect estimations. This suggests that RM and PV methods should be avoided to analyze longitudinal latent variables. Copyright © 2010 John Wiley & Sons, Ltd.

Rasch model based analysis of the Force Concept Inventory

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Maja Planinic

2010-03-01

Full Text Available The Force Concept Inventory (FCI is an important diagnostic instrument which is widely used in the field of physics education research. It is therefore very important to evaluate and monitor its functioning using different tools for statistical analysis. One of such tools is the stochastic Rasch model, which enables construction of linear measures for persons and items from raw test scores and which can provide important insight in the structure and functioning of the test (how item difficulties are distributed within the test, how well the items fit the model, and how well the items work together to define the underlying construct. The data for the Rasch analysis come from the large-scale research conducted in 2006-07, which investigated Croatian high school students’ conceptual understanding of mechanics on a representative sample of 1676 students (age 17–18 years. The instrument used in research was the FCI. The average FCI score for the whole sample was found to be (27.7±0.4%, indicating that most of the students were still non-Newtonians at the end of high school, despite the fact that physics is a compulsory subject in Croatian schools. The large set of obtained data was analyzed with the Rasch measurement computer software WINSTEPS 3.66. Since the FCI is routinely used as pretest and post-test on two very different types of population (non-Newtonian and predominantly Newtonian, an additional predominantly Newtonian sample (N=141, average FCI score of 64.5% of first year students enrolled in introductory physics course at University of Zagreb was also analyzed. The Rasch model based analysis suggests that the FCI has succeeded in defining a sufficiently unidimensional construct for each population. The analysis of fit of data to the model found no grossly misfitting items which would degrade measurement. Some items with larger misfit and items with significantly different difficulties in the two samples of students do require further

A psychometric revision of the European American Values Scale for Asian Americans using the Rasch model

OpenAIRE

Hong, S; Kim, Bryan S.K.; Wolfe, M M

2005-01-01

The 18-item European American Values Scale for Asian Americans (M. M. Wolfe, P H. Yang, E C. Wong, & D. R. Atkinson, 2001) was revised on the basis of results from a psychometric analysis using the Rasch Model (G. Rasch,1960). The results led to the establishment of the 25-item European AmericanValues Scale for Asian Americans-Revised.

TESTING THE ASSUMPTIONS AND INTERPRETING THE RESULTS OF THE RASCH MODEL USING LOG-LINEAR PROCEDURES IN SPSS

NARCIS (Netherlands)

TENVERGERT, E; GILLESPIE, M; KINGMA, J

This paper shows how to use the log-linear subroutine of SPSS to fit the Rasch model. It also shows how to fit less restrictive models obtained by relaxing specific assumptions of the Rasch model. Conditional maximum likelihood estimation was achieved by including dummy variables for the total

Improving the Individual Work Performance Questionnaire using Rasch analysis.

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Koopmans, L.; Bernaards, C.M.; Hildebrandt, V.H.; Buuren, S. van; Beek, A.J. van der; Vet, H.C.W. de

2014-01-01

Recently, the Individual Work Performance Questionnaire (IWPQ) version 0.2 was developed using Rasch analysis. The goal of the current study was to improve targeting of the IWPQ scales by including additional items. The IWPQ 0.2 (original) and 0.3 (including additional items) were examined using

USING RASCH ANALYSIS TO EXPLORE WHAT STUDENTS LEARN ABOUT PROBABILITY CONCEPTS

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Zamalia Mahmud

2015-01-01

Full Text Available Students’ understanding of probability concepts have been investigated from various different perspectives. This study was set out to investigate perceived understanding of probability concepts of forty-four students from the STAT131 Understanding Uncertainty and Variation course at the University of Wollongong, NSW. Rasch measurement which is based on a probabilistic model was used to identify concepts that students find easy, moderate and difficult to understand. Data were captured from the e-learning Moodle platform where students provided their responses through an on-line quiz. As illustrated in the Rasch map, 96% of the students could understand about sample space, simple events, mutually exclusive events and tree diagram while 67% of the students found concepts of conditional and independent events rather easy to understand

Using Rasch Analysis To Explore What Students Learn About Probability Concepts

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Zamalia Mahmud

2015-01-01

Full Text Available Students’ understanding of probability concepts have been investigated from various different perspectives. This study was set out to investigate perceived understanding of probability concepts of forty-four students from the STAT131 Understanding Uncertainty and Variation course at the University of Wollongong, NSW. Rasch measurement which is based on a probabilistic model was used to identify concepts that students find easy, moderate and difficult to understand. Data were captured from the e-learning Moodle platform where students provided their responses through an on-line quiz. As illustrated in the Rasch map, 96% of the students could understand about sample space, simple events, mutually exclusive events and tree diagram while 67% of the students found concepts of conditional and independent events rather easy to understand.

An Analysis of Cross Racial Identity Scale Scores Using Classical Test Theory and Rasch Item Response Models

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Sussman, Joshua; Beaujean, A. Alexander; Worrell, Frank C.; Watson, Stevie

2013-01-01

Item response models (IRMs) were used to analyze Cross Racial Identity Scale (CRIS) scores. Rasch analysis scores were compared with classical test theory (CTT) scores. The partial credit model demonstrated a high goodness of fit and correlations between Rasch and CTT scores ranged from 0.91 to 0.99. CRIS scores are supported by both methods.…

Rasch scaling of the Oswestry Disability Index and the Roland-Morris Disability Questionnaire

DEFF Research Database (Denmark)

Lauridsen, Henrik Hein; Hartvigsen, Jan

Questionnaire (RMQ) and the Oswestry Disability Index (ODI), however, only few studies have tested these questionnaires using Rasch analysis. This study used Rasch scaling to test the construct validity of the Danish versions of the RMQ (23-item Patrick version) and the ODI (version 2.1a) in a heterogeneous...... on an ordinal scale into interval scaling in addition to optimising the fit of instrument items to the target population. In low back pain research the two most commonly used and well-validated questionnaires to assess functional status in patients with low back pain are the Roland-Morris Disability...

Quantitative Reasoning in Environmental Science: Rasch Measurement to Support QR Assessment

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Robert L. Mayes

2015-07-01

Full Text Available The ability of middle and high school students to reason quantitatively within the context of environmental science was investigated. A quantitative reasoning (QR learning progression, with associated QR assessments in the content areas of biodiversity, water, and carbon, was developed based on three QR progress variables: quantification act, quantitative interpretation, and quantitative modeling. Diagnostic instruments were developed specifically for the progress variable quantitative interpretation (QI, each consisting of 96 Likert-scale items. Each content version of the instrument focused on three scale levels (macro scale, micro scale, and landscape scale and four elements of QI identified in prior research (trend, translation, prediction, and revision. The QI assessments were completed by 362, 6th to 12th grade students in three U.S. states. Rasch (1960/1980 measurement was used to determine item and person measures for the QI instruments, both to examine validity and reliability characteristics of the instrument administration and inform the evolution of the learning progression. Rasch methods allowed identification of several QI instrument revisions, including modification of specific items, reducing number of items to avoid cognitive fatigue, reconsidering proposed item difficulty levels, and reducing Likert scale to 4 levels. Rasch diagnostics also indicated favorable levels of instrument reliability and appropriate targeting of item abilities to student abilities for the majority of participants. A revised QI instrument is available for STEM researchers and educators.

Is ionizing radiation regulated more stringently than chemical carcinogens

International Nuclear Information System (INIS)

Travis, C.C.; Pack, S.R.; Hattemer-Frey, H.A.

1989-01-01

It is widely believed that United States government agencies regulate exposure to ionizing radiation more stringently than exposure to chemical carcinogens. It is difficult to verify this perception, however, because chemical carcinogens and ionizing radiation are regulated using vastly different strategies. Chemical carcinogens are generally regulated individually. Regulators consider the risk of exposure to one chemical rather than the cumulative radiation exposure from all sources. Moreover, standards for chemical carcinogens are generally set in terms of quantities released or resultant environmental concentrations, while standards for ionizing radiation are set in terms of dose to the human body. Since chemicals and ionizing radiation cannot be compared on the basis of equal dose to the exposed individual, standards regulating chemicals and ionizing radiation cannot be compared directly. It is feasible, however, to compare the two sets of standards on the basis of equal risk to the exposed individual, assuming that standards for chemicals and ionizing radiation are equivalent if estimated risk levels are equitable. This paper compares risk levels associated with current standards for ionizing radiation and chemical carcinogens. The authors do not attempt to determine whether either type of risk is regulated too stringently or not stringently enough but endeavor only to ascertain if ionizing radiation is actually regulated more strictly than chemical carcinogens

Validating Quantitative Measurement Using Qualitative Data: Combining Rasch Scaling and Latent Semantic Analysis in Psychiatry

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Lange, Rense

2015-02-01

An extension of concurrent validity is proposed that uses qualitative data for the purpose of validating quantitative measures. The approach relies on Latent Semantic Analysis (LSA) which places verbal (written) statements in a high dimensional semantic space. Using data from a medical / psychiatric domain as a case study - Near Death Experiences, or NDE - we established concurrent validity by connecting NDErs qualitative (written) experiential accounts with their locations on a Rasch scalable measure of NDE intensity. Concurrent validity received strong empirical support since the variance in the Rasch measures could be predicted reliably from the coordinates of their accounts in the LSA derived semantic space (R2 = 0.33). These coordinates also predicted NDErs age with considerable precision (R2 = 0.25). Both estimates are probably artificially low due to the small available data samples (n = 588). It appears that Rasch scalability of NDE intensity is a prerequisite for these findings, as each intensity level is associated (at least probabilistically) with a well- defined pattern of item endorsements.

Rasch Calibration of Perceived Weights of Different Sports Games

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Kang, Sang-Jo; Kang, Minsoo

2006-01-01

In many countries, an athlete's performance at sporting competitions is often used as part of the selection criteria for entry into college. These criteria could be biased depending upon the procedures utilized by the authorities in a particular country. The purpose of this study was to calibrate, by using the Rasch rating scale model, the…

Emotional Intelligence and Nurse Recruitment: Rasch and confirmatory factor analysis of the trait emotional intelligence questionnaire short form.

Science.gov (United States)

Snowden, Austyn; Watson, Roger; Stenhouse, Rosie; Hale, Claire

2015-12-01

To examine the construct validity of the Trait Emotional Intelligence Questionnaire Short form. Emotional intelligence involves the identification and regulation of our own emotions and the emotions of others. It is therefore a potentially useful construct in the investigation of recruitment and retention in nursing and many questionnaires have been constructed to measure it. Secondary analysis of existing dataset of responses to Trait Emotional Intelligence Questionnaire Short form using concurrent application of Rasch analysis and confirmatory factor analysis. First year undergraduate nursing and computing students completed Trait Emotional Intelligence Questionnaire-Short Form in September 2013. Responses were analysed by synthesising results of Rasch analysis and confirmatory factor analysis. Participants (N = 938) completed Trait Emotional Intelligence Questionnaire Short form. Rasch analysis showed the majority of the Trait Emotional Intelligence Questionnaire-Short Form items made a unique contribution to the latent trait of emotional intelligence. Five items did not fit the model and differential item functioning (gender) accounted for this misfit. Confirmatory factor analysis revealed a four-factor structure consisting of: self-confidence, empathy, uncertainty and social connection. All five misfitting items from the Rasch analysis belonged to the 'social connection' factor. The concurrent use of Rasch and factor analysis allowed for novel interpretation of Trait Emotional Intelligence Questionnaire Short form. Much of the response variation in Trait Emotional Intelligence Questionnaire Short form can be accounted for by the social connection factor. Implications for practice are discussed. © 2015 John Wiley & Sons Ltd.

Power analysis on the time effect for the longitudinal Rasch model.

Science.gov (United States)

Feddag, M L; Blanchin, M; Hardouin, J B; Sebille, V

2014-01-01

Statistics literature in the social, behavioral, and biomedical sciences typically stress the importance of power analysis. Patient Reported Outcomes (PRO) such as quality of life and other perceived health measures (pain, fatigue, stress,...) are increasingly used as important health outcomes in clinical trials or in epidemiological studies. They cannot be directly observed nor measured as other clinical or biological data and they are often collected through questionnaires with binary or polytomous items. The Rasch model is the well known model in the item response theory (IRT) for binary data. The article proposes an approach to evaluate the statistical power of the time effect for the longitudinal Rasch model with two time points. The performance of this method is compared to the one obtained by simulation study. Finally, the proposed approach is illustrated on one subscale of the SF-36 questionnaire.

Measuring Instrument Constructs of Return Factors for Green Office Building Investments Variables Using Rasch Measurement Model

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Isa Mona

2016-01-01

Full Text Available This paper is a preliminary study on rationalising green office building investments in Malaysia. The aim of this paper is attempt to introduce the application of Rasch measurement model analysis to determine the validity and reliability of each construct in the questionnaire. In achieving this objective, a questionnaire survey was developed consists of 6 sections and a total of 106 responses were received from various investors who own and lease office buildings in Kuala Lumpur. The Rasch Measurement analysis is used to measure the quality control of item constructs in the instrument by measuring the specific objectivity within the same dimension, to reduce ambiguous measures, and a realistic estimation of precision and implicit quality. The Rasch analysis consists of the summary statistics, item unidimensionality and item measures. A result shows the items and respondent (person reliability is at 0.91 and 0.95 respectively.

Self-report measure of financial exploitation of older adults.

Science.gov (United States)

Conrad, Kendon J; Iris, Madelyn; Ridings, John W; Langley, Kate; Wilber, Kathleen H

2010-12-01

this study was designed to improve the measurement of financial exploitation (FE) by testing psychometric properties of the older adult financial exploitation measure (OAFEM), a client self-report instrument. rasch item response theory and traditional validation approaches were used. Questionnaires were administered by 22 adult protective services investigators from 7 agencies in Illinois to 227 substantiated abuse clients. Analyses included tests for dimensionality, model fit, and additional construct validation. Results from the OAFEM were also compared with the substantiation decision of abuse and with investigators' assessments of FE using a staff report version. Hypotheses were generated to test hypothesized relationships. the OAFEM, including the original 79-, 54-, and 30-item measures, met stringent Rasch analysis fit and unidimensionality criteria and had high internal consistency and item reliability. The validation results were supportive, while leading to reconsideration of aspects of the hypothesized theoretical hierarchy. Thresholds were suggested to demonstrate levels of severity. the measure is now available to aid in the assessment of FE of older adults by both clinicians and researchers. Theoretical refinements developed using the empirically generated item hierarchy may help to improve assessment and intervention.

Assessing social isolation in motor neurone disease: a Rasch analysis of the MND Social Withdrawal Scale.

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Gibbons, Chris J; Thornton, Everard W; Ealing, John; Shaw, Pamela J; Talbot, Kevin; Tennant, Alan; Young, Carolyn A

2013-11-15

Social withdrawal is described as the condition in which an individual experiences a desire to make social contact, but is unable to satisfy that desire. It is an important issue for patients with motor neurone disease who are likely to experience severe physical impairment. This study aims to reassess the psychometric and scaling properties of the MND Social Withdrawal Scale (MND-SWS) domains and examine the feasibility of a summary scale, by applying scale data to the Rasch model. The MND Social Withdrawal Scale was administered to 298 patients with a diagnosis of MND, alongside the Hospital Anxiety and Depression Scale. The factor structure of the MND Social Withdrawal Scale was assessed using confirmatory factor analysis. Model fit, category threshold analysis, differential item functioning (DIF), dimensionality and local dependency were evaluated. Factor analysis confirmed the suitability of the four-factor solution suggested by the original authors. Mokken scale analysis suggested the removal of item five. Rasch analysis removed a further three items; from the Community (one item) and Emotional (two items) withdrawal subscales. Following item reduction, each scale exhibited excellent fit to the Rasch model. A 14-item Summary scale was shown to fit the Rasch model after subtesting the items into three subtests corresponding to the Community, Family and Emotional subscales, indicating that items from these three subscales could be summed together to create a total measure for social withdrawal. Removal of four items from the Social Withdrawal Scale led to a four factor solution with a 14-item hierarchical Summary scale that were all unidimensional, free for DIF and well fitted to the Rasch model. The scale is reliable and allows clinicians and researchers to measure social withdrawal in MND along a unidimensional construct. © 2013. Published by Elsevier B.V. All rights reserved.

Obtaining Content Weights for Test Specifications from Job Analysis Task Surveys: An Application of the Many-Facets Rasch Model

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Wang, Ning; Stahl, John

2012-01-01

This article discusses the use of the Many-Facets Rasch Model, via the FACETS computer program (Linacre, 2006a), to scale job/practice analysis survey data as well as to combine multiple rating scales into single composite weights representing the tasks' relative importance. Results from the Many-Facets Rasch Model are compared with those…

Psychometric validation of the Persian Bergen Social Media Addiction Scale using classic test theory and Rasch models.

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Lin, Chung-Ying; Broström, Anders; Nilsen, Per; Griffiths, Mark D; Pakpour, Amir H

2017-12-01

Background and aims The Bergen Social Media Addiction Scale (BSMAS), a six-item self-report scale that is a brief and effective psychometric instrument for assessing at-risk social media addiction on the Internet. However, its psychometric properties in Persian have never been examined and no studies have applied Rasch analysis for the psychometric testing. This study aimed to verify the construct validity of the Persian BSMAS using confirmatory factor analysis (CFA) and Rasch models among 2,676 Iranian adolescents. Methods In addition to construct validity, measurement invariance in CFA and differential item functioning (DIF) in Rasch analysis across gender were tested for in the Persian BSMAS. Results Both CFA [comparative fit index (CFI) = 0.993; Tucker-Lewis index (TLI) = 0.989; root mean square error of approximation (RMSEA) = 0.057; standardized root mean square residual (SRMR) = 0.039] and Rasch (infit MnSq = 0.88-1.28; outfit MnSq = 0.86-1.22) confirmed the unidimensionality of the BSMAS. Moreover, measurement invariance was supported in multigroup CFA including metric invariance (ΔCFI = -0.001; ΔSRMR = 0.003; ΔRMSEA = -0.005) and scalar invariance (ΔCFI = -0.002; ΔSRMR = 0.005; ΔRMSEA = 0.001) across gender. No item displayed DIF (DIF contrast = -0.48 to 0.24) in Rasch across gender. Conclusions Given the Persian BSMAS was unidimensional, it is concluded that the instrument can be used to assess how an adolescent is addicted to social media on the Internet. Moreover, users of the instrument may comfortably compare the sum scores of the BSMAS across gender.

Assessment of upper limb capacity in children with unilateral cerebral palsy: construct validity of a Rasch-reduced Modified House Classification

NARCIS (Netherlands)

Geerdink, Yvonne; Lindeboom, Robert; de Wolf, Sander; Steenbergen, Bert; Geurts, Alexander C. H.; Aarts, Pauline

2014-01-01

The aim of this study was to test and improve the unidimensionality and item hierarchy of the Modified House Classification (MHC) for the assessment of upper limb capacity in children with unilateral cerebral palsy (CP) using Rasch analysis. The construct validity of the Rasch-reduced item set was

Rasch analysis suggested three unidimensional domains for Affiliate Stigma Scale: additional psychometric evaluation.

Science.gov (United States)

Chang, Chih-Cheng; Su, Jian-An; Tsai, Ching-Shu; Yen, Cheng-Fang; Liu, Jiun-Horng; Lin, Chung-Ying

2015-06-01

To examine the psychometrics of the Affiliate Stigma Scale using rigorous psychometric analysis: classical test theory (CTT) (traditional) and Rasch analysis (modern). Differential item functioning (DIF) items were also tested using Rasch analysis. Caregivers of relatives with mental illness (n = 453; mean age: 53.29 ± 13.50 years) were recruited from southern Taiwan. Each participant filled out four questionnaires: Affiliate Stigma Scale, Rosenberg Self-Esteem Scale, Beck Anxiety Inventory, and one background information sheet. CTT analyses showed that the Affiliate Stigma Scale had satisfactory internal consistency (α = 0.85-0.94) and concurrent validity (Rosenberg Self-Esteem Scale: r = -0.52 to -0.46; Beck Anxiety Inventory: r = 0.27-0.34). Rasch analyses supported the unidimensionality of three domains in the Affiliate Stigma Scale and indicated four DIF items (affect domain: 1; cognitive domain: 3) across gender. Our findings, based on rigorous statistical analysis, verified the psychometrics of the Affiliate Stigma Scale and reported its DIF items. We conclude that the three domains of the Affiliate Stigma Scale can be separately used and are suitable for measuring the affiliate stigma of caregivers of relatives with mental illness. Copyright © 2015 Elsevier Inc. All rights reserved.

Evaluation of the Edinburgh Post Natal Depression Scale using Rasch analysis

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Tennant Alan

2006-06-01

Full Text Available Abstract Background The Edinburgh Postnatal Depression Scale (EPDS is a 10 item self-rating post-natal depression scale which has seen widespread use in epidemiological and clinical studies. Concern has been raised over the validity of the EPDS as a single summed scale, with suggestions that it measures two separate aspects, one of depressive feelings, the other of anxiety. Methods As part of a larger cross-sectional study conducted in Melbourne, Australia, a community sample (324 women, ranging in age from 18 to 44 years: mean = 32 yrs, SD = 4.6, was obtained by inviting primiparous women to participate voluntarily in this study. Data from the EPDS were fitted to the Rasch measurement model and tested for appropriate category ordering, for item bias through Differential Item Functioning (DIF analysis, and for unidimensionality through tests of the assumption of local independence. Results Rasch analysis of the data from the ten item scale initially demonstrated a lack of fit to the model with a significant Item-Trait Interaction total chi-square (chi Square = 82.8, df = 40; p Conclusion The results of this study suggest that EPDS, in its original 10 item form, is not a viable scale for the unidimensional measurement of depression. Rasch analysis suggests that a revised eight item version (EPDS-8 would provide a more psychometrically robust scale. The revised cut points of 7/8 and 9/10 for the EPDS-8 show high levels of agreement with the original case identification for the EPDS-10.

Rasch Analysis: A Primer for School Psychology Researchers and Practitioners

Science.gov (United States)

Boone, William J.; Noltemeyer, Amity

2017-01-01

In order to progress as a field, school psychology research must be informed by effective measurement techniques. One approach to address the need for careful measurement is Rasch analysis. This technique can (a) facilitate the development of instruments that provide useful data, (b) provide data that can be used confidently for both descriptive…

Rasch scaling paranormal belief and experience: structure and semantics of Thalbourne's Australian Sheep-Goat Scale.

Science.gov (United States)

Lange, Rense; Thalbourne, Michael A

2002-12-01

Research on the relation between demographic variables and paranormal belief remains controversial given the possible semantic distortions introduced by item and test level biases. We illustrate how Rasch scaling can be used to detect such biases and to quantify their effects, using the Australian Sheep-Goal Scale as a substantive example. Based on data from 1.822 respondents, this test was Rasch scalable, reliable, and unbiased at the test level. Consistent with other research in which unbiased measures of paranormal belief were used, extremely weak age and sex effects were found (partial eta2 = .005 and .012, respectively).

Estimating the Multilevel Rasch Model: With the lme4 Package

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Harold Doran

2007-02-01

Full Text Available Traditional Rasch estimation of the item and student parameters via marginal maximum likelihood, joint maximum likelihood or conditional maximum likelihood, assume individuals in clustered settings are uncorrelated and items within a test that share a grouping structure are also uncorrelated. These assumptions are often violated, particularly in educational testing situations, in which students are grouped into classrooms and many test items share a common grouping structure, such as a content strand or a reading passage. Consequently, one possible approach is to explicitly recognize the clustered nature of the data and directly incorporate random effects to account for the various dependencies. This article demonstrates how the multilevel Rasch model can be estimated using the functions in R for mixed-effects models with crossed or partially crossed random effects. We demonstrate how to model the following hierarchical data structures: a individuals clustered in similar settings (e.g., classrooms, schools, b items nested within a particular group (such as a content strand or a reading passage, and c how to estimate a teacher × content strand interaction.

Higher Education End-of-Course Evaluations: Assessing the Psychometric Properties Utilizing Exploratory Factor Analysis and Rasch Modeling Approaches

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Kelly D. Bradley

2016-07-01

Full Text Available This paper offers a critical assessment of the psychometric properties of a standard higher education end-of-course evaluation. Using both exploratory factor analysis (EFA and Rasch modeling, the authors investigate the (a an overall assessment of dimensionality using EFA, (b a secondary assessment of dimensionality using a principal components analysis (PCA of the residuals when the items are fit to the Rasch model, and (c an assessment of item-level properties using item-level statistics provided when the items are fit to the Rasch model. The results support the usage of the scale as a supplement to high-stakes decision making such as tenure. However, the lack of precise targeting of item difficulty to person ability combined with the low person separation index renders rank-ordering professors according to minuscule differences in overall subscale scores a highly questionable practice.

The construct validity of the Major Depression Inventory: A Rasch analysis of a self-rating scale in primary care.

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Nielsen, Marie Germund; Ørnbøl, Eva; Vestergaard, Mogens; Bech, Per; Christensen, Kaj Sparle

2017-06-01

We aimed to assess the measurement properties of the ten-item Major Depression Inventory when used on clinical suspicion in general practice by performing a Rasch analysis. General practitioners asked consecutive persons to respond to the web-based Major Depression Inventory on clinical suspicion of depression. We included 22 practices and 245 persons. Rasch analysis was performed using RUMM2030 software. The Rasch model fit suggests that all items contribute to a single underlying trait (defined as internal construct validity). Mokken analysis was used to test dimensionality and scalability. Our Rasch analysis showed misfit concerning the sleep and appetite items (items 9 and 10). The response categories were disordered for eight items. After modifying the original six-point to a four-point scoring system for all items, we achieved ordered response categories for all ten items. The person separation reliability was acceptable (0.82) for the initial model. Dimensionality testing did not support combining the ten items to create a total score. The scale appeared to be well targeted to this clinical sample. No significant differential item functioning was observed for gender, age, work status and education. The Rasch and Mokken analyses revealed two dimensions, but the Major Depression Inventory showed fit to one scale if items 9 and 10 were excluded. Our study indicated scalability problems in the current version of the Major Depression Inventory. The conducted analysis revealed better statistical fit when items 9 and 10 were excluded. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of High School German Textbooks through Rasch Measurement Model

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Batdi, Veli; Elaldi, Senel

2016-01-01

The purpose of the present study is to analyze German teacher trainers' views on high school German textbooks through the Rasch measurement model. A survey research design was employed and study group consisted of a total of 21 teacher trainers, three from each region and selected randomly from provinces which are located in seven regions and…

Application of Rasch analysis to the parent adherence report questionnaire in juvenile idiopathic arthritis.

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Toupin April, Karine; Higgins, Johanne; Ehrmann Feldman, Debbie

2016-07-28

Adherence to treatment in children with juvenile idiopathic arthritis (JIA) is associated with better outcomes. Assessing patient adherence in JIA, as well as attitudes and beliefs about prescribed treatments, is important for the clinician in order to optimize patient management. The objective of the current study was to evaluate the psychometric properties of the Parent (proxy-report) Adherence Report Questionnaires (PARQ), which assesses beliefs and behaviors related to adherence to treatments prescribed for JIA. A Rasch analysis was conducted on data collected with parents of children with JIA from two studies in which the PARQ was used as a measure of adherence. The PARQ showed preliminary evidence of multidimensionality with two factors, accounting for 38 % and 27 % of the variance respectively. The PARQ in its original version does not adhere to expectations of the Rasch model. A transformed version of the PARQ obtained by deletion of the general adherence scale and modification of visual analog scales into 5-point likert scales improved fit to the model and showed preliminary evidence of unidimensionality. The PARQ was transformed based on the results of the Rasch analysis. The transformed version of the PARQ shows preliminary evidence of unidimensionality and may allow computation of a total score, although further testing is needed to verify these findings.

%lrasch_mml: A SAS Macro for Marginal Maximum Likelihood Estimation in Longitudinal Polytomous Rasch Models

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Maja Olsbjerg

2015-10-01

Full Text Available Item response theory models are often applied when a number items are used to measure a unidimensional latent variable. Originally proposed and used within educational research, they are also used when focus is on physical functioning or psychological wellbeing. Modern applications often need more general models, typically models for multidimensional latent variables or longitudinal models for repeated measurements. This paper describes a SAS macro that fits two-dimensional polytomous Rasch models using a specification of the model that is sufficiently flexible to accommodate longitudinal Rasch models. The macro estimates item parameters using marginal maximum likelihood estimation. A graphical presentation of item characteristic curves is included.

Rasch Analysis of the Adult Strabismus Quality of Life Questionnaire (AS-20 among Chinese Adult Patients with Strabismus.

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Zonghua Wang

Full Text Available The impact of strabismus on visual function, self-image, self-esteem, and social interactions decrease health-related quality of life (HRQoL.The purpose of this study was to evaluate and refine the adult strabismus quality of life questionnaire (AS-20 by using Rasch analysis among Chinese adult patients with strabismus.We evaluated the fitness of the AS-20 with Rasch model in Chinese population by assessing unidimensionality, infit and outfit, person and item separation index and reliability, response ordering, targeting and differential item functioning (DIF.The overall AS-20 did not demonstrate unidimensional; however, it was achieved separately in the two Rasch-revised subscales: the psychosocial subscale (11 items and the function subscale (9 items. The features of good targeting, optimal item infit and outfit, and no notable local dependence were found for each of the subscales. The rating scale was appropriate for the psychosocial subscale but a reduction to four response categories was required for the function subscale. No significant DIF were revealed for any demographic and clinical factors (e.g., age, gender, and strabismus types.The AS-20 was demonstrated by Rasch analysis to be a rigorous instrument for measuring health-related quality of life in Chinese strabismus patents if some revisions were made regarding the subscale construct and response options.

Spurious Latent Class Problem in the Mixed Rasch Model: A Comparison of Three Maximum Likelihood Estimation Methods under Different Ability Distributions

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Sen, Sedat

2018-01-01

Recent research has shown that over-extraction of latent classes can be observed in the Bayesian estimation of the mixed Rasch model when the distribution of ability is non-normal. This study examined the effect of non-normal ability distributions on the number of latent classes in the mixed Rasch model when estimated with maximum likelihood…

Scale construction utilising the Rasch unidimensional measurement model: A measurement of adolescent attitudes towards abortion

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Jacqueline Hendriks

2012-05-01

Full Text Available BackgroundMeasurement scales seeking to quantify latent traits likeattitudes, are often developed using traditionalpsychometric approaches. Application of the Raschunidimensional measurement model may complement orreplace these techniques, as the model can be used toconstruct scales and check their psychometric properties. Ifdata fit the model, then a scale with invariant measurementproperties, including interval-level scores, will have beendeveloped.AimsThis paper highlights the unique properties of the Raschmodel. Items developed to measure adolescent attitudestowards abortion are used to exemplify the process.MethodTen attitude and intention items relating to abortion wereanswered by 406 adolescents aged 12 to 19 years, as part ofthe “Teen Relationships Study”. The sampling frameworkcaptured a range of sexual and pregnancy experiences.Items were assessed for fit to the Rasch model includingchecks for Differential Item Functioning (DIF by gender,sexual experience or pregnancy experience.ResultsRasch analysis of the original dataset initially demonstratedthat some items did not fit the model. Rescoring of one item(B5 and removal of another (L31 resulted in fit, as shownby a non-significant item-trait interaction total chi-squareand a mean log residual fit statistic for items of -0.05(SD=1.43. No DIF existed for the revised scale. However,items did not distinguish as well amongst persons with themost intense attitudes as they did for other persons. Aperson separation index of 0.82 indicated good reliability.ConclusionApplication of the Rasch model produced a valid andreliable scale measuring adolescent attitudes towardsabortion, with stable measurement properties. The Raschprocess provided an extensive range of diagnosticinformation concerning item and person fit, enablingchanges to be made to scale items. This example shows thevalue of the Rasch model in developing scales for bothsocial science and health disciplines.

Rasch validation of the Chinese parent-child interaction scale (CPCIS).

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Ip, Patrick; Tso, Winnie; Rao, Nirmala; Ho, Frederick Ka Wing; Chan, Ko Ling; Fu, King Wa; Li, Sophia Ling; Goh, Winnie; Wong, Wilfred Hing-Sang; Chow, Chun Bong

2018-03-15

Proper parent-child interaction is crucial for child development, but an assessment tool in Chinese is currently lacking. This study aimed to develop and validate a parent-reported parent-child interaction scale for Chinese preschool children. The Chinese parent-child interaction scale (CPCIS) was designed by an expert panel based on the literature and clinical observations in the Chinese context. The initial CPCIS had 14 parent-child interactive activity items. Psychometric properties of the CPCIS were examined using the Rasch model and confirmatory factor analysis (CFA). Convergent validity was investigated by the associations between CPCIS and family income, maternal education level, and children's school readiness. The study recruited 567 Chinese parent-child pairs from diverse socioeconomic backgrounds, who completed the CPCIS. Six out of the 14 items in the initial CPCIS were dropped due to suboptimal fit values. The refined 8-item CPCIS was shown to be valid and reliable by Rasch models and CFA. The person separation reliability and Cronbach's α of the CPCIS were 0.81 and 0.82, respectively. The CPCIS scores were positively associated with family's socioeconomic status (η 2  = 0.05, P parent-child interactions in Chinese families.

Rasch family models in e-learning: analyzing architectural sketching with a digital pen.

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Scalise, Kathleen; Cheng, Nancy Yen-Wen; Oskui, Nargas

2009-01-01

Since architecture students studying design drawing are usually assessed qualitatively on the basis of their final products, the challenges and stages of their learning have remained masked. To clarify the challenges in design drawing, we have been using the BEAR Assessment System and Rasch family models to measure levels of understanding for individuals and groups, in order to correct pedagogical assumptions and tune teaching materials. This chapter discusses the analysis of 81 drawings created by architectural students to solve a space layout problem, collected and analyzed with digital pen-and-paper technology. The approach allows us to map developmental performance criteria and perceive achievement overlaps in learning domains assumed separate, and then re-conceptualize a three-part framework to represent learning in architectural drawing. Results and measurement evidence from the assessment and Rasch modeling are discussed.

A Rasch Analysis of the Junior Metacognitive Awareness Inventory with Singapore Students

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Ning, Hoi Kwan

2018-01-01

The psychometric properties of the 2 versions of the Junior Metacognitive Awareness Inventory were examined with Singapore student samples. Other than 2 misfitting items and an underutilized response scale, Rasch analysis demonstrated that the instruments have good measurement precision, and no differential item functioning was detected across…

Multi-faceted Rasch measurement and bias patterns in EFL writing performance assessment.

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He, Tung-Hsien; Gou, Wen Johnny; Chien, Ya-Chen; Chen, I-Shan Jenny; Chang, Shan-Mao

2013-04-01

This study applied multi-faceted Rasch measurement to examine rater bias in the assessment of essays written by college students learning English as a foreign language. Four raters who had received different academic training from four distinctive disciplines applied a six-category rating scale to analytically rate essays on an argumentative topic and on a descriptive topic. FACETS, a Rasch computer program, was utilized to pinpoint bias patterns by analyzing the rater-topic, rater-category, and topic-category interactions. Results showed: argumentative essays were rated more severely than were descriptive essays; the linguistics-major rater was the most lenient rater, while the literature-major rater was the severest one; and the category of language use received the severest ratings, whereas content was given the most lenient ratings. The severity hierarchies for raters, essay topics, and rating categories suggested that raters' academic training and their perceptions of the importance of categories were associated with their bias patterns. Implications for rater training are discussed.

Validation of the brief version of the Recovery Self-Assessment (RSA-B) using Rasch measurement theory.

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Barbic, Skye P; Kidd, Sean A; Davidson, Larry; McKenzie, Kwame; O'Connell, Maria J

2015-12-01

In psychiatry, the recovery paradigm is increasingly identified as the overarching framework for service provision. Currently, the Recovery Self-Assessment (RSA), a 36-item rating scale, is commonly used to assess the uptake of a recovery orientation in clinical services. However, the consumer version of the RSA has been found challenging to complete because of length and the reading level required. In response to this feedback, a brief 12-item version of the RSA was developed (RSA-B). This article describes the development of the modified instrument and the application of traditional psychometric analysis and Rasch Measurement Theory to test the psychometrics properties of the RSA-B. Data from a multisite study of adults with serious mental illnesses (n = 1256) who were followed by assertive community treatment teams were examined for reliability, clinical meaning, targeting, response categories, model fit, reliability, dependency, and raw interval-level measurement. Analyses were performed using the Rasch Unidimensional Measurement Model (RUMM 2030). Adequate fit to the Rasch model was observed (χ2 = 112.46, df = 90, p = .06) and internal consistency was good (r = .86). However, Rasch analysis revealed limitations of the 12-item version, with items covering only 39% of the targeted theoretical continuum, 2 misfitting items, and strong evidence for the 5 option response categories not working as intended. This study revealed areas for improvement in the shortened version of the 12-item RSA-B. A revisit of the conceptual model and original 36-item rating scale is encouraged to select items that will help practitioners and researchers measure the full range of recovery orientation. (c) 2015 APA, all rights reserved).

Revalidating the Arabic Scale for Teachers' Ratings of Basic Education Gifted Students' Characteristics Using Rasch Modeling

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Salah Eldin Farah Atallah Bakheit

2013-12-01

Full Text Available The Arabic scale for teachers' ratings of basic education gifted students' characteristics is one of the most common Arabic measures used for initial identification of gifted students in some Arabic countries. One of the shortcomings of this scale is that it is based on the classical the-ory of measurement. This study sought to reval-idate the scale in the light of Rasch modeling which rests upon the modern theory of meas-urement and to develop different criteria for in-terpreting the levels of individuals' traits. The scale was administered to 830 of Basic Educa-tion students in Khartoum (ages ranged from 7 to 12 years. Two groups of students partici-pated in the study: a calibration sample (N = 250 and a standardization sample (N = 580. The statistical treatments were performed using the PSAW 18 and RUMM 2020 programs ac-cording to Rasch's unidimentional model. Six of the scale's items were deleted for not conform-ing to Rasch Modeling. This left the scale with 31 items. Besides, new criteria for the scale were developed by obtaining the t-scores and special education scores that match the various ratings of the individuals' ability.

Orphan Toxin OrtT (YdcX) of Escherichia coli Reduces Growth during the Stringent Response

Science.gov (United States)

2015-01-29

antimicrobials trimethoprim and sulfamethoxazole; these antimicrobials induce the stringent response by inhibiting tetrahydrofolate synthesis...in the presence of both antimicrobials trimethoprim and sulfamethoxazole; these antimicrobials induce the stringent response by inhibiting...level [20]. Toxins 2015, 7 301 Despite these difficulties in determining physiological roles, TA systems are clearly phage inhibition systems

A psychometric revision of the Asian values scale using the Rasch model

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Kim, Bryan S. K.; Hong, Sehee

2004-01-01

The 36-item Asian Values Scale (B. S. K. Kim, D. R. Atkinson, & P H. Yang, 1999) was revised on the basis of G. Rasch (1960) model and data from 618 Asian Americans. The results led to the establishment of a 25-item measure named the Asian Values Scale-Revised.

Rasch Analysis of the Fullerton Advanced Balance (FAB) Scale

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Fiedler, Roger C.; Rose, Debra J.

2011-01-01

ABSTRACT Purpose: This cross-sectional study explores the psychometric properties and dimensionality of the Fullerton Advanced Balance (FAB) Scale, a multi-item balance test for higher-functioning older adults. Methods: Participants (n=480) were community-dwelling adults able to ambulate independently. Data gathering consisted of survey and balance performance assessment. Psychometric properties were assessed using Rasch analysis. Results: Mean age of participants was 76.4 (SD=7.1) years. Mean FAB Scale scores were 24.7/40 (SD=7.5). Analyses for scale dimensionality showed that 9 of the 10 items fit a unidimensional measure of balance. Item 10 (Reactive Postural Control) did not fit the model. The reliability of the scale to separate persons was 0.81 out of 1.00; the reliability of the scale to separate items in terms of their difficulty was 0.99 out of 1.00. Cronbach's alpha for a 10-item model was 0.805. Items of differing difficulties formed a useful ordinal hierarchy for scaling patterns of expected balance ability scoring for a normative population. Conclusion: The FAB Scale appears to be a reliable and valid tool to assess balance function in higher-functioning older adults. The test was found to discriminate among participants of varying balance abilities. Further exploration of concurrent validity of Rasch-generated expected item scoring patterns should be undertaken to determine the test's diagnostic and prescriptive utility. PMID:22210989

Rasch Analysis of the Fullerton Advanced Balance (FAB) Scale.

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Klein, Penelope J; Fiedler, Roger C; Rose, Debra J

2011-01-01

This cross-sectional study explores the psychometric properties and dimensionality of the Fullerton Advanced Balance (FAB) Scale, a multi-item balance test for higher-functioning older adults. Participants (n=480) were community-dwelling adults able to ambulate independently. Data gathering consisted of survey and balance performance assessment. Psychometric properties were assessed using Rasch analysis. Mean age of participants was 76.4 (SD=7.1) years. Mean FAB Scale scores were 24.7/40 (SD=7.5). Analyses for scale dimensionality showed that 9 of the 10 items fit a unidimensional measure of balance. Item 10 (Reactive Postural Control) did not fit the model. The reliability of the scale to separate persons was 0.81 out of 1.00; the reliability of the scale to separate items in terms of their difficulty was 0.99 out of 1.00. Cronbach's alpha for a 10-item model was 0.805. Items of differing difficulties formed a useful ordinal hierarchy for scaling patterns of expected balance ability scoring for a normative population. The FAB Scale appears to be a reliable and valid tool to assess balance function in higher-functioning older adults. The test was found to discriminate among participants of varying balance abilities. Further exploration of concurrent validity of Rasch-generated expected item scoring patterns should be undertaken to determine the test's diagnostic and prescriptive utility.

A developmental screening tool for toddlers with multiple domains based on Rasch analysis.

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Hwang, Ai-Wen; Chou, Yeh-Tai; Hsieh, Ching-Lin; Hsieh, Wu-Shiun; Liao, Hua-Fang; Wong, Alice May-Kuen

2015-01-01

Using multidomain developmental screening tools is a feasible method for pediatric health care professionals to identify children at risk of developmental problems in multiple domains simultaneously. The purpose of this study was to develop a Rasch-based tool for Multidimensional Screening in Child Development (MuSiC) for children aged 0-3 years. The MuSic was developed by constructing items bank based on three commonly used screening tools, validating with developmental status (at risk for delay or not) on five developmental domains. Parents of a convenient sample of 632 children (aged 3-35.5 months) with and without developmental delays responded to items from the three screening tools funded by health authorities in Taiwan. Item bank was determined by item fit of Rasch analysis for each of the five developmental domains (cognitive skills, language skills, gross motor skills, fine motor skills, and socioadaptive skills). Children's performance scores in logits derived in Rasch analysis were validated with developmental status for each domain using the area under receiver operating characteristic curves. MuSiC, a 75-item developmental screening tool for five domains, was derived. The diagnostic validity of all five domains was acceptable for all stages of development, except for the infant stage (≤11 months and 15 days). MuSiC can be applied simultaneously to well-child care visits as a universal screening tool for children aged 1-3 years on multiple domains. Items with sound validity for infants need to be further developed. Copyright © 2014. Published by Elsevier B.V.

Calibration of a Chemistry Test Using the Rasch Model

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Nancy Coromoto Martín Guaregua

2011-11-01

Full Text Available The Rasch model was used to calibrate a general chemistry test for the purpose of analyzing the advantages and information the model provides. The sample was composed of 219 college freshmen. Of the 12 questions used, good fit was achieved in 10. The evaluation shows that although there are items of variable difficulty, there are gaps on the scale; in order to make the test complete, it will be necessary to design new items to fill in these gaps.

Stringent DDI-based prediction of H. sapiens-M. tuberculosis H37Rv protein-protein interactions.

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Zhou, Hufeng; Rezaei, Javad; Hugo, Willy; Gao, Shangzhi; Jin, Jingjing; Fan, Mengyuan; Yong, Chern-Han; Wozniak, Michal; Wong, Limsoon

2013-01-01

H. sapiens-M. tuberculosis H37Rv protein-protein interaction (PPI) data are very important information to illuminate the infection mechanism of M. tuberculosis H37Rv. But current H. sapiens-M. tuberculosis H37Rv PPI data are very scarce. This seriously limits the study of the interaction between this important pathogen and its host H. sapiens. Computational prediction of H. sapiens-M. tuberculosis H37Rv PPIs is an important strategy to fill in the gap. Domain-domain interaction (DDI) based prediction is one of the frequently used computational approaches in predicting both intra-species and inter-species PPIs. However, the performance of DDI-based host-pathogen PPI prediction has been rather limited. We develop a stringent DDI-based prediction approach with emphasis on (i) differences between the specific domain sequences on annotated regions of proteins under the same domain ID and (ii) calculation of the interaction strength of predicted PPIs based on the interacting residues in their interaction interfaces. We compare our stringent DDI-based approach to a conventional DDI-based approach for predicting PPIs based on gold standard intra-species PPIs and coherent informative Gene Ontology terms assessment. The assessment results show that our stringent DDI-based approach achieves much better performance in predicting PPIs than the conventional approach. Using our stringent DDI-based approach, we have predicted a small set of reliable H. sapiens-M. tuberculosis H37Rv PPIs which could be very useful for a variety of related studies. We also analyze the H. sapiens-M. tuberculosis H37Rv PPIs predicted by our stringent DDI-based approach using cellular compartment distribution analysis, functional category enrichment analysis and pathway enrichment analysis. The analyses support the validity of our prediction result. Also, based on an analysis of the H. sapiens-M. tuberculosis H37Rv PPI network predicted by our stringent DDI-based approach, we have discovered some

Teater vajab ellujäämiseks värsket dramaturgiat / Jane Rasch ; vahendanud Eva-Liisa Linder

Index Scriptorium Estoniae

Rasch, Jane

2009-01-01

Taani teatriteadlane Jane Rasch õpetas 10.-14. augustini 2009 Viljandi Kultuuriakadeemias toimunud draamakirjutuskursusel "Ideedest näidendi stsenaariumini". Ka näitekirjanike koolitamisest Taanis jt. Põhjamaades

Quantifying Local, Response Dependence between Two Polytomous Items Using the Rasch Model

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Andrich, David; Humphry, Stephen M.; Marais, Ida

2012-01-01

Models of modern test theory imply statistical independence among responses, generally referred to as "local independence." One violation of local independence occurs when the response to one item governs the response to a subsequent item. Expanding on a formulation of this kind of violation as a process in the dichotomous Rasch model,…

Accounting for Local Dependence with the Rasch Model: The Paradox of Information Increase.

Science.gov (United States)

Andrich, David

Test theories imply statistical, local independence. Where local independence is violated, models of modern test theory that account for it have been proposed. One violation of local independence occurs when the response to one item governs the response to a subsequent item. Expanding on a formulation of this kind of violation between two items in the dichotomous Rasch model, this paper derives three related implications. First, it formalises how the polytomous Rasch model for an item constituted by summing the scores of the dependent items absorbs the dependence in its threshold structure. Second, it shows that as a consequence the unit when the dependence is accounted for is not the same as if the items had no response dependence. Third, it explains the paradox, known, but not explained in the literature, that the greater the dependence of the constituent items the greater the apparent information in the constituted polytomous item when it should provide less information.

Measuring parental stress in mothers of infants: A Rasch-based construct validity study

DEFF Research Database (Denmark)

Nielsen, Tine; Pontoppidan, Maiken; Kristensen, Ingeborg Hedegaard

of the Danish language version of the PSS in a community sample of 1110 mothers of children aged 0 to 12 months employing the Rasch family of IRT models, and emphasizing the issues of unidimensionality and equal item functioning (no DIF) relative to the age and educational levels of the mothers. No adequate fit......) were found each to fit so-called graphical loglinear Rasch models: The parental stress subscale fit a model adjusted for local response dependence between some item pairs, as well as DIF for one item relative to mothers’ level of education and DIF for another item relative to age and educational level...... of the mothers. The parental satisfaction subscale fit a model adjusted only for local response dependence. The findings are in line with the original interpretation of the PSS. We recommend that the scoring of the PSS is changed to reflect the two subscales and the dichotomization of response categories...

Using the Rasch Measurement Model in Psychometric Analysis of the Family Effectiveness Measure

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McCreary, Linda L.; Conrad, Karen M.; Conrad, Kendon J.; Scott, Christy K; Funk, Rodney R.; Dennis, Michael L.

2013-01-01

Background Valid assessment of family functioning can play a vital role in optimizing client outcomes. Because family functioning is influenced by family structure, socioeconomic context, and culture, existing measures of family functioning--primarily developed with nuclear, middle class European American families--may not be valid assessments of families in diverse populations. The Family Effectiveness Measure was developed to address this limitation. Objectives To test the Family Effectiveness Measure with data from a primarily low-income African American convenience sample, using the Rasch measurement model. Method A sample of 607 adult women completed the measure. Rasch analysis was used to assess unidimensionality, response category functioning, item fit, person reliability, differential item functioning by race and parental status, and item hierarchy. Criterion-related validity was tested using correlations with five other variables related to family functioning. Results The Family Effectiveness Measure measures two separate constructs: The effective family functioning construct was a psychometrically sound measure of the target construct that was more efficient due to the deletion of 22 items. The ineffective family functioning construct consisted of 16 of those deleted items but was not as strong psychometrically. Items in both constructs evidenced no differential item functioning by race. Criterion-related validity was supported for both. Discussion In contrast to the prevailing conceptualization that family functioning is a single construct, assessed by positively and negatively worded items, use of the Rasch analysis suggested the existence of two constructs. While the effective family functioning is a strong and efficient measure of family functioning, the ineffective family functioning will require additional item development and psychometric testing. PMID:23636342

Análise de Rasch aplicada a questionário sobre consumo de tabaco em escolares adolescentes = Rasch analysis applied to a questionnaire on tobacco use among adolescent students

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Santos, Wendel Mombaque dos

2014-01-01

Conclusões: O uso do método de Rasch possibilitou verificar a exposição de cada participante às diferentes condições de exposição ao tabaco, assim como demonstrou que o questionário que avalia a exposição ao tabaco deve tratar cada questão com pesos diferentes

Factors associated with knowledge of diabetes in patients with type 2 diabetes using the Diabetes Knowledge Test validated with Rasch analysis.

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Eva K Fenwick

Full Text Available OBJECTIVE: In patients with Type 2 diabetes, to determine the factors associated with diabetes knowledge, derived from Rasch analysis, and compare results with a traditional raw scoring method. RESEARCH DESIGN & METHODS: Participants in this cross-sectional study underwent a comprehensive clinical and biochemical assessment. Diabetes knowledge (main outcome was assessed using the Diabetes Knowledge Test (DKT which was psychometrically validated using Rasch analysis. The relationship between diabetes knowledge and risk factors identified during univariate analyses was examined using multivariable linear regression. The results using raw and Rasch-transformed methods were descriptively compared. RESULTS: 181 patients (mean age±standard deviation = 66.97±9.17 years; 113 (62% male were included. Using Rasch-derived DKT scores, those with greater education (β = 1.14; CI: 0.25,2.04, p = 0.013; had seen an ophthalmologist (β = 1.65; CI: 0.63,2.66, p = 0.002, and spoke English at home (β = 1.37; CI: 0.43,2.31, p = 0.005 had significantly better diabetes knowledge than those with less education, had not seen an ophthalmologist and spoke a language other than English, respectively. Patients who were members of the National Diabetes Service Scheme (NDSS and had seen a diabetes educator also had better diabetes knowledge than their counterparts. Higher HbA1c level was independently associated with worse diabetes knowledge. Using raw measures, access to an ophthalmologist and NDSS membership were not independently associated with diabetes knowledge. CONCLUSIONS: Sociodemographic, clinical and service use factors were independently associated with diabetes knowledge based on both raw scores and Rasch-derived scores, which supports the implementation of targeted interventions to improve patients' knowledge. Choice of psychometric analytical method can affect study outcomes and should be considered during intervention

Factors Associated with Knowledge of Diabetes in Patients with Type 2 Diabetes Using the Diabetes Knowledge Test Validated with Rasch Analysis

Science.gov (United States)

Fenwick, Eva K.; Xie, Jing; Rees, Gwyn; Finger, Robert P.; Lamoureux, Ecosse L.

2013-01-01

Objective In patients with Type 2 diabetes, to determine the factors associated with diabetes knowledge, derived from Rasch analysis, and compare results with a traditional raw scoring method. Research Design & Methods Participants in this cross-sectional study underwent a comprehensive clinical and biochemical assessment. Diabetes knowledge (main outcome) was assessed using the Diabetes Knowledge Test (DKT) which was psychometrically validated using Rasch analysis. The relationship between diabetes knowledge and risk factors identified during univariate analyses was examined using multivariable linear regression. The results using raw and Rasch-transformed methods were descriptively compared. Results 181 patients (mean age±standard deviation = 66.97±9.17 years; 113 (62%) male) were included. Using Rasch-derived DKT scores, those with greater education (β = 1.14; CI: 0.25,2.04, p = 0.013); had seen an ophthalmologist (β = 1.65; CI: 0.63,2.66, p = 0.002), and spoke English at home (β = 1.37; CI: 0.43,2.31, p = 0.005) had significantly better diabetes knowledge than those with less education, had not seen an ophthalmologist and spoke a language other than English, respectively. Patients who were members of the National Diabetes Service Scheme (NDSS) and had seen a diabetes educator also had better diabetes knowledge than their counterparts. Higher HbA1c level was independently associated with worse diabetes knowledge. Using raw measures, access to an ophthalmologist and NDSS membership were not independently associated with diabetes knowledge. Conclusions Sociodemographic, clinical and service use factors were independently associated with diabetes knowledge based on both raw scores and Rasch-derived scores, which supports the implementation of targeted interventions to improve patients' knowledge. Choice of psychometric analytical method can affect study outcomes and should be considered during intervention development. PMID:24312484

A longitudinal evaluation of the Center for Epidemiologic Studies-Depression scale (CES-D) in a Rheumatoid Arthritis Population using Rasch Analysis

Science.gov (United States)

Covic, Tanya; Pallant, Julie F; Conaghan, Philip G; Tennant, Alan

2007-01-01

Background The aim of this study was to test the internal validity of the total Center for Epidemiologic Studies-Depression (CES-D) scale using Rasch analysis in a rheumatoid arthritis (RA) population. Methods CES-D was administered to 157 patients with RA over three time points within a 12 month period. Rasch analysis was applied using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF) and person separation. Results Pooled data across three time points was shown to fit the Rasch model with removal of seven items from the original 20-item CES-D scale. It was necessary to rescore the response format from four to three categories in order to improve the scale's fit. Two items demonstrated some DIF for age and gender but were retained within the 13-item CES-D scale. A new cut point for depression score of 9 was found to correspond to the original cut point score of 16 in the full CES-D scale. Conclusion This Rasch analysis of the CES-D in a longstanding RA cohort resulted in the construction of a modified 13-item scale with good internal validity. Further validation of the modified scale is recommended particularly in relation to the new cut point for depression. PMID:17629902

A longitudinal evaluation of the Center for Epidemiologic Studies-Depression scale (CES-D in a Rheumatoid Arthritis Population using Rasch Analysis

Directory of Open Access Journals (Sweden)

Tennant Alan

2007-07-01

Full Text Available Abstract Background The aim of this study was to test the internal validity of the total Center for Epidemiologic Studies-Depression (CES-D scale using Rasch analysis in a rheumatoid arthritis (RA population. Methods CES-D was administered to 157 patients with RA over three time points within a 12 month period. Rasch analysis was applied using RUMM2020 software to assess the overall fit of the model, the response scale used, individual item fit, differential item functioning (DIF and person separation. Results Pooled data across three time points was shown to fit the Rasch model with removal of seven items from the original 20-item CES-D scale. It was necessary to rescore the response format from four to three categories in order to improve the scale's fit. Two items demonstrated some DIF for age and gender but were retained within the 13-item CES-D scale. A new cut point for depression score of 9 was found to correspond to the original cut point score of 16 in the full CES-D scale. Conclusion This Rasch analysis of the CES-D in a longstanding RA cohort resulted in the construction of a modified 13-item scale with good internal validity. Further validation of the modified scale is recommended particularly in relation to the new cut point for depression.

Electricity versus hydrogen for passenger cars under stringent climate change control

NARCIS (Netherlands)

Rösler, H.; van der Zwaan, B.; Keppo, I.; Bruggink, J.

2014-01-01

In this article we analyze how passenger car transportation in Europe may change this century under permanent high oil prices and stringent climate control policy. We focus on electricity and hydrogen as principal candidate energy carriers, because these two options are increasingly believed to

Historical Views of Invariance: Evidence from the Measurement Theories of Thorndike, Thurstone, and Rasch.

Science.gov (United States)

Engelhard, George, Jr.

1992-01-01

A historical perspective is provided of the concept of invariance in measurement theory, describing sample-invariant item calibration and item-invariant measurement of individuals. Invariance as a key measurement concept is illustrated through the measurement theories of E. L. Thorndike, L. L. Thurstone, and G. Rasch. (SLD)

A Rasch and confirmatory factor analysis of the General Health Questionnaire (GHQ - 12

Directory of Open Access Journals (Sweden)

Velikova Galina

2010-04-01

Full Text Available Abstract Background The General Health Questionnaire (GHQ - 12 was designed as a short questionnaire to assess psychiatric morbidity. Despite the fact that studies have suggested a number of competing multidimensional factor structures, it continues to be largely used as a unidimensional instrument. This may have an impact on the identification of psychiatric morbidity in target populations. The aim of this study was to explore the dimensionality of the GHQ-12 and to evaluate a number of alternative models for the instrument. Methods The data were drawn from a large heterogeneous sample of cancer patients. The Partial Credit Model (Rasch was applied to the 12-item GHQ. Item misfit (infit mean square ≥ 1.3 was identified, misfitting items removed and unidimensionality and differential item functioning (age, gender, and treatment aims were assessed. The factor structures of the various alternative models proposed in the literature were explored and optimum model fit evaluated using Confirmatory Factor Analysis. Results The Rasch analysis of the 12-item GHQ identified six misfitting items. Removal of these items produced a six-item instrument which was not unidimensional. The Rasch analysis of an 8-item GHQ demonstrated two unidimensional structures corresponding to Anxiety/Depression and Social Dysfunction. No significant differential item functioning was observed by age, gender and treatment aims for the six- and eight-item GHQ. Two models competed for best fit from the confirmatory factor analysis, namely the GHQ-8 and Hankin's (2008 unidimensional model, however, the GHQ-8 produced the best overall fit statistics. Conclusions The results are consistent with the evidence that the GHQ-12 is a multi-dimensional instrument. Use of the summated scores for the GHQ-12 could potentially lead to an incorrect assessment of patients' psychiatric morbidity. Further evaluation of the GHQ-12 with different target populations is warranted.

Thorndike, Thurstone and Rasch: A Comparison of Their Approaches to Item-Invariant Measurement.

Science.gov (United States)

Englehard, George, Jr.

The methods used by E. L. Thorndike, L. L. Thurstone, and G. Rasch to address issues related to item-invariant measurement and the scoring of individual performance are compared. The analyses highlight the close connection among the three methods, and suggest that progress in measurement theory reflects the movement from essentially ad hoc methods…

El modelo de rasch en dirección de operaciones

Directory of Open Access Journals (Sweden)

Lidia Sanchez

2012-11-01

Full Text Available Durante décadas, en el área de Dirección de Operaciones, se ha destacado la necesidad de un acercamiento entre el mundo académico y el profesional, reclamando la realización de estudios empíricos que aporten soluciones prácticas a los profesionales. De ahí que durante los últimos años se hayan producido dos fenómenos clave: la convergencia entre los temas objeto de investigación y los temas de interés para las empresas; y un aumento en el  número de estudios empíricos realizados.Ahora bien, otro factor importantísimo a la hora de aportar conocimientos prácticos a la disciplina es la herramienta o metodología aplicada. Por ello, el desarrollo de nuevas herramientas o la aplicación de otras ya existentes en otros campos es un tema interesante. Es en este punto donde adquiere importancia la Metodología de Rasch.Esta técnica ha sido tradicionalmente utilizada en disciplinas tales como la Psicología o la Medicina. Sin embargo, ya hace algunos años, ha comenzado a utilizarse en otras áreas de conocimiento, entre ellas, el área de Administración y Dirección de Empresas. No obstante, su aplicación al área concreta de Operaciones es escasa y, por ello, las posibilidades de desarrollo e investigaciones futuras son numerosas.La Metodología de Rasch, útil para el diseño y la explotación de encuestas, se basa en tres principios, unidimensionalidad, aditividad e invarianza, y permite obtener medidas objetivas a partir del análisis de variables categóricas. Entre sus múltiples aplicaciones destacamos las siguientes: análisis de la viabilidad y fiabilidad globales, análisis de la unidimensionalidad del constructo, análisis de escalas del cuestionario, priorización (ordenación de los ítems y/o de los sujetos, análisis DAFO… Es, por lo tanto, una metodología muy rica con multitud de posibilidades para su aplicación en la disciplina.Dado su incipiente desarrollo en esta área de conocimiento el objetivo de este

Using the Rasch model as an objective and probabilistic technique to integrate different soil properties

Science.gov (United States)

Rebollo, Francisco J.; Jesús Moral García, Francisco

2016-04-01

Soil apparent electrical conductivity (ECa) is one of the simplest, least expensive soil measurements that integrates many soil properties affecting crop productivity, including, for instance, soil texture, water content, and cation exchange capacity. The ECa measurements obtained with a 3100 Veris sensor, operating in both shallow (0-30 cm), ECs, and deep (0-90 cm), ECd, mode, can be used as an additional and essential information to be included in a probabilistic model, the Rasch model, with the aim of quantifying the overall soil fertililty potential in an agricultural field. This quantification should integrate the main soil physical and chemical properties, with different units. In this work, the formulation of the Rasch model integrates 11 soil properties (clay, silt and sand content, organic matter -OM-, pH, total nitrogen -TN-, available phosphorus -AP- and potassium -AK-, cation exchange capacity -CEC-, ECd, and ECs) measured at 70 locations in a field. The main outputs of the model include a ranking of all soil samples according to their relative fertility potential and the unexpected behaviours of some soil samples and properties. In the case study, the considered soil variables fit the model reasonably, having an important influence on soil fertility, except pH, probably due to its homogeneity in the field. Moreover, ECd, ECs are the most influential properties on soil fertility and, on the other hand, AP and AK the less influential properties. The use of the Rasch model to estimate soil fertility potential (always in a relative way, taking into account the characteristics of the studied soil) constitutes a new application of great practical importance, enabling to rationally determine locations in a field where high soil fertility potential exists and establishing those soil samples or properties which have any anomaly; this information can be necessary to conduct site-specific treatments, leading to a more cost-effective and sustainable field

Validity of the Neuromuscular Recovery Scale: a measurement model approach.

Science.gov (United States)

Velozo, Craig; Moorhouse, Michael; Ardolino, Elizabeth; Lorenz, Doug; Suter, Sarah; Basso, D Michele; Behrman, Andrea L

2015-08-01

To determine how well the Neuromuscular Recovery Scale (NRS) items fit the Rasch, 1-parameter, partial-credit measurement model. Confirmatory factor analysis (CFA) and principal components analysis (PCA) of residuals were used to determine dimensionality. The Rasch, 1-parameter, partial-credit rating scale model was used to determine rating scale structure, person/item fit, point-measure item correlations, item discrimination, and measurement precision. Seven NeuroRecovery Network clinical sites. Outpatients (N=188) with spinal cord injury. Not applicable. NRS. While the NRS met 1 of 3 CFA criteria, the PCA revealed that the Rasch measurement dimension explained 76.9% of the variance. Ten of 11 items and 91% of the patients fit the Rasch model, with 9 of 11 items showing high discrimination. Sixty-nine percent of the ratings met criteria. The items showed a logical item-difficulty order, with Stand retraining as the easiest item and Walking as the most challenging item. The NRS showed no ceiling or floor effects and separated the sample into almost 5 statistically distinct strata; individuals with an American Spinal Injury Association Impairment Scale (AIS) D classification showed the most ability, and those with an AIS A classification showed the least ability. Items not meeting the rating scale criteria appear to be related to the low frequency counts. The NRS met many of the Rasch model criteria for construct validity. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

MetHumi - Humidity Device for Mars MetNet Lander

Science.gov (United States)

Genzer, Maria; Polkko, Jouni; Harri, Ari-Matti; Schmidt, Walter; Leinonen, Jussi; Mäkinen, Teemu; Haukka, Harri

2010-05-01

MetNet Mars Mission focused for Martian atmospheric science is based on a new semihard landing vehicle called the MetNet Lander (MNL). The MNL will have a versatile science payload focused on the atmospheric science of Mars. The scientific payload of the MetNet Mission encompasses separate instrument packages for the atmospheric entry and descent phase and for the surface operation phase. MetHumi is the humidity sensor of MetNet Lander designed to work on Martian surface. It is based on Humicap® technology developed by Vaisala, Inc. MetHumi is a capacitive type of sensing device where an active polymer film changes capacitance as function of relative humidity. One MetHumi device package consists of one humidity transducer including three Humicap® sensor heads, an accurate temperature sensor head (Thermocap® by Vaisala, Inc.) and constant reference channels. MetHumi is very small, lightweighed and has low power consumption. It weighs only about 15 g without wires, and consumes 15 mW of power. MetHumi can make meaningful relative humidity measurements in range of 0 - 100%RH down to -70°C ambient temperature, but it survives even -135°C ambient temperature.

On the Construct Validity of the Academic Motivation Scale: a CFA and Rasch Analysis approach

DEFF Research Database (Denmark)

Andersen, Martin Stolpe; Nielsen, Tine

subscales measuring Extrinsic Motivation (EM) and one scale measuring Amotivation (AM), each with 4 items. The AMS was translated into Danish and data was collected from psychology students (N = 607) at two Danish universities in 6 different study terms. The construct validity of the seven scales was first...... investigated using confirmatory factor analysis with mixed results of some acceptable and some non-acceptable fit indices for the model. Secondly, Rasch analyses were conducted for each of the seven subscales, using the partial credit model (PCM) and graphical loglinear rasch models (GLLRM). This resulted...... in fit to the PCM in the case of IM to Accomplish (retaining three out of four items), and fit to GLLRMs in two cases: 1) IM to know with evidence of local dependence between all four items. 2) AM (retaining three out of four items) with evidence of gender-based differential item functioning, which...

Met kerse op met -konstruksies 1 : 'n Verwysingspuntperspektief ...

African Journals Online (AJOL)

Met kerse op met-konstruksies1: 'n Verwysingspuntperspektief. Johanna Messerschmidt, Luna Bergh. Abstract. This article analyses the usage of the Afrikaans preposition met ('with'). The analysis is done within the framework of Cognitive Linguistics and more specifically within the model proposed by Langacker (1993) ...

Evaluation of the Edinburgh Post Natal Depression Scale using Rasch analysis

Science.gov (United States)

Pallant, Julie F; Miller, Renée L; Tennant, Alan

2006-01-01

Background The Edinburgh Postnatal Depression Scale (EPDS) is a 10 item self-rating post-natal depression scale which has seen widespread use in epidemiological and clinical studies. Concern has been raised over the validity of the EPDS as a single summed scale, with suggestions that it measures two separate aspects, one of depressive feelings, the other of anxiety. Methods As part of a larger cross-sectional study conducted in Melbourne, Australia, a community sample (324 women, ranging in age from 18 to 44 years: mean = 32 yrs, SD = 4.6), was obtained by inviting primiparous women to participate voluntarily in this study. Data from the EPDS were fitted to the Rasch measurement model and tested for appropriate category ordering, for item bias through Differential Item Functioning (DIF) analysis, and for unidimensionality through tests of the assumption of local independence. Results Rasch analysis of the data from the ten item scale initially demonstrated a lack of fit to the model with a significant Item-Trait Interaction total chi-square (chi Square = 82.8, df = 40; p < .001). Removal of two items (items 7 and 8) resulted in a non-significant Item-Trait Interaction total chi-square with a residual mean value for items of -0.467 with a standard deviation of 0.850, showing fit to the model. No DIF existed in the final 8-item scale (EPDS-8) and all items showed fit to model expectations. Principal Components Analysis of the residuals supported the local independence assumption, and unidimensionality of the revised EPDS-8 scale. Revised cut points were identified for EPDS-8 to maintain the case identification of the original scale. Conclusion The results of this study suggest that EPDS, in its original 10 item form, is not a viable scale for the unidimensional measurement of depression. Rasch analysis suggests that a revised eight item version (EPDS-8) would provide a more psychometrically robust scale. The revised cut points of 7/8 and 9/10 for the EPDS-8 show high

Linguistic validation of stigmatisation degree, self-esteem and knowledge questionnaire among asthma patients using Rasch analysis.

Science.gov (United States)

Ahmad, Sohail; Ismail, Ahmad Izuanuddin; Khan, Tahir Mehmood; Akram, Waqas; Mohd Zim, Mohd Arif; Ismail, Nahlah Elkudssiah

2017-04-01

The stigmatisation degree, self-esteem and knowledge either directly or indirectly influence the control and self-management of asthma. To date, there is no valid and reliable instrument that can assess these key issues collectively. The main aim of this study was to test the reliability and validity of the newly devised and translated "Stigmatisation Degree, Self-Esteem and Knowledge Questionnaire" among adult asthma patients using the Rasch measurement model. This cross-sectional study recruited thirty adult asthma patients from two respiratory specialist clinics in Selangor, Malaysia. The newly devised self-administered questionnaire was adapted from relevant publications and translated into the Malay language using international standard translation guidelines. Content and face validation was done. The data were extracted and analysed for real item reliability and construct validation using the Rasch model. The translated "Stigmatisation Degree, Self-Esteem and Knowledge Questionnaire" showed high real item reliability values of 0.90, 0.86 and 0.89 for stigmatisation degree, self-esteem, and knowledge of asthma, respectively. Furthermore, all values of point measure correlation (PTMEA Corr) analysis were within the acceptable specified range of the Rasch model. Infit/outfit mean square values and Z standard (ZSTD) values of each item verified the construct validity and suggested retaining all the items in the questionnaire. The reliability analyses and output tables of item measures for construct validation proved the translated Malaysian version of "Stigmatisation Degree, Self-Esteem and Knowledge Questionnaire" as a valid and highly reliable questionnaire.

MetBaro - Pressure Device for Mars MetNet Lander

Science.gov (United States)

Haukka, Harri; Polkko, Jouni; Harri, Ari-Matti; Schmidt, Walter; Leinonen, Jussi; Genzer, Maria; Mäkinen, Teemu

2010-05-01

MetNet Mars Mission focused for Martian atmospheric science is based on a new semihard landing vehicle called the MetNet Lander (MNL). The MNL will have a versatile science payload focused on the atmospheric science of Mars. The scientific payload of the MetNet Mission encompasses separate instrument packages for the atmospheric entry and descent phase and for the surface operation phase. MetBaro is the pressure sensor of MetNet Lander designed to work on Martian surface. It is based on Barocap® technology developed by Vaisala, Inc. MetBaro is a capacitive type of sensing device where capasitor plates are moved by ambient pressure. MetBaro device consists of two pressure transducers including a total of 4 Barocap® sensor heads of high-stability and high-resolution types. The long-term stability of MetBaro is in order of 20…50 µBar and resolution a few µBar. MetBaro is small, lightweighed and has low power consumption. It weighs about 50g without wires and controlling FPGA, and consumes 15 mW of power. A similar device has successfully flown in Phoenix mission, where it performed months of measurements on Martian ground. Another device is also part of the Mars Science Laboratory REMS instrument (to be launched in 2011).

Psychometric properties of the International Classification of Functioning, Disability and Health set for spinal cord injury nursing based on Rasch analysis.

Science.gov (United States)

Li, Kun; Yan, Tiebin; You, Liming; Xie, Sumei; Li, Yun; Tang, Jie; Wang, Yingmin; Gao, Yan

2018-02-01

To examine the psychometric properties of the International Classification of Functioning, Disability and Health (ICF) set for spinal cord injury nursing (ICF-SCIN) using Rasch analysis. A total of 140 spinal cord injury patients were recruited between December 2013 and March 2014 through convenience sampling. Nurses used the components body functions (BF), body structures (BS), and activities and participation (AP) of the ICF-SCIN to rate the patients' functioning. Rasch analysis was performed using RUMM 2030 software. In each component, categories were rescored from 01234 to 01112 because of reversed thresholds. Nine testlets were created to overcome local dependency. Four categories which fit to the Rasch model poorly were deleted. After modification, the components BF, BS, and AP showed good fit to the Rasch model with a Bonferroni-adjusted significant level (χ 2  =   86.29, p = 0.006; χ 2  =   22.44, p = 0.130; χ 2  =   39.92, p = 0.159). The person separation indices (PSIs) for the three components were 0.80, 0.54, and 0.97, respectively. No differential item functioning (DIF) was detected across age, gender, or educational level. The fit properties of the ICF set were satisfactory after modifications. The ICF-SCIN has the potential as a nursing assessment instrument for measuring the functioning of patients with spinal cord injury. Implications for rehabilitation The International Classification of Functioning, Disability and Health (ICF) set for spinal cord injury nursing contains a group of categories which can reflect the functioning of spinal cord injury patients from the perspective of nurses. The components body functions (BF), body structures (BS), and activities and participation (AP) of the ICF set for spinal cord injury achieved the fit to the Rasch model through rescoring, generating testlets, and deleting categories with poor fit. The ICF set for spinal cord injury nursing (ICF-SCIN) has the potential to be used as a

Analysis of the Professional Choice Self-Efficacy Scale Using the Rasch-Andrich Rating Scale Model

Science.gov (United States)

Ambiel, Rodolfo A. M.; Noronha, Ana Paula Porto; de Francisco Carvalho, Lucas

2015-01-01

The aim of this research was to analyze the psychometrics properties of the professional choice self-efficacy scale (PCSES), using the Rasch-Andrich rating scale model. The PCSES assesses four factors: self-appraisal, gathering occupational information, practical professional information search and future planning. Participants were 883 Brazilian…

Latent trait standardization of the benzodiazepine dependence self-report questionnaire using the Rasch scaling model.

NARCIS (Netherlands)

Kan, C.C.; Ven, A.H.G.S. van der; Breteler, M.H.M.; Zitman, F.G.

2001-01-01

The aim of the present study was to obtain standardized scores that correspond with the raw scores on the four Rasch scales of the Benzodiazepine Dependence-Self Report Questionnaire (Bendep-SRQ). The eligible normative group for standardization of the Bendep-SRQ scales consisted of 217 general

Latent Trait Standardization of the Benzodiazepine Dependence Self-Report Questionnaire using the Rasch Scaling Model

NARCIS (Netherlands)

Kan, C.C.; Ven, A.H.G.S. van der; Breteler, M.H.M.; Zitman, F.G.

2001-01-01

The aim of the present study was to obtain standardized scores that correspond with the raw scores on the four Rasch scales of the Benzodiazepine Dependence-Self Report Questionnaire (Bendep-SRQ). The eligible normative group for standardization of the Bendep-SRQ scales consisted of 217 general

Rasch analysis of the Rosenberg Self-Esteem Scale with African Americans.

Science.gov (United States)

Chao, Ruth Chu-Lien; Vidacovich, Courtney; Green, Kathy E

2017-03-01

Effectively diagnosing African Americans' self-esteem has posed an unresolved challenge. To address this assessment issue, we conducted exploratory factor analysis and Rasch analysis to assess the psychometric characteristics of the Rosenberg Self-Esteem Scale (RSES, Rosenberg, 1965) for African American college students. The dimensional structure of the RSES was first identified with the first subsample (i.e., calibration subsample) and then held up under cross-validation with a second subsample (i.e., validation subsample). Exploratory factor analysis and Rasch analysis both supported unidimensionality of the measure, with that finding replicated for a random split of the sample. Response scale use was generally appropriate, items were endorsed at a high level reflecting high levels of self-esteem, and person separation and reliability of person separation were adequate, and reflected results similar to those found in prior research. However, as some categories were infrequently used, we also collapsed scale points and found a slight improvement in scale and item indices. No differential item functioning was found by sex or having received professional assistance versus not; there were no mean score differences by age group, marital status, or year in college. Two items were seen as problematic. Implications for theory and research on multicultural mental health are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Catquest-9SF questionnaire: validation of Malay and Chinese-language versions using Rasch analysis.

Science.gov (United States)

Adnan, Tassha Hilda; Mohamed Apandi, Mokhlisoh; Kamaruddin, Haireen; Salowi, Mohamad Aziz; Law, Kian Boon; Haniff, Jamaiyah; Goh, Pik Pin

2018-01-05

Catquest questionnaire was originally developed in Swedish to measure patients' self-assessed visual function to evaluate the benefit of cataract surgery. The result of the Rasch analysis leading to the creation of the nine-item short form of Catquest, (Catquest-9SF), and it had been translated and validated in English. The aim is therefore to evaluate the translated Catquest-9SF questionnaire in Malay and Chinese (Mandarin) language version for measuring patient-reported visual function among cataract population in Malaysia. The English version of Catquest-9SF questionnaire was translated and back translated into Malay and Chinese languages. The Malay and Chinese translated versions were self-administered by 236 and 202 pre-operative patients drawn from a cataract surgery waiting list, respectively. The translated Catquest-9SF data and its four response options were assessed for fit to the Rasch model. The Catquest-9SF performed well in the Malay and Chinese translated versions fulfilling all criteria for valid measurement, as demonstrated by Rasch analysis. Both versions of questionnaire had ordered response thresholds, with a good person separation (Malay 2.84; and Chinese 2.59) and patient separation reliability (Malay 0.89; Chinese 0.87). Targeting was 0.30 and -0.11 logits in Malay and Chinese versions respectively, indicating that the item difficulty was well suited to the visual abilities of the patients. All items fit a single overall construct (Malay infit range 0.85-1.26, outfit range 0.73-1.13; Chinese infit range 0.80-1.51, outfit range 0.71-1.36), unidimensional by principal components analysis, and was free of Differential Item Functioning (DIF). These results support the good overall functioning of the Catquest-9SF in patients with cataract. The translated questionnaire to Malay and Chinese-language versions are reliable and valid in measuring visual disability outcomes in the Malaysian cataract population.

MetBaro - Pressure Instrument for Mars MetNet Lander

Science.gov (United States)

Polkko, J.; Haukka, H.; Harri, A.-M.; Schmidt, W.; Leinonen, J.; Mäkinen, T.

2009-04-01

THE METNET MISSION FOCUSED ON THE Martian atmospheric science is based on a new semihard landing vehicle called the MetNet Lander (MNL). The MNL will have a versatile science payload focused on the atmospheric science of Mars. The scientific payload of the MetNet Mission encompasses separate instrument packages for the atmospheric entry and descent phase and for the surface operation phase. MetBaro is the pressure instrument of MetNet Lander designed to work on Martian surface. It is based on Barocap® technology developed by Vaisala, Inc. MetBaro is a capacitic type of sensing device where capasitor plates are moved by ambient pressure. MetBaro device consists of two pressure transducers including a total of 6 Barocap® sensor heads of high-stability and high-resolution types. The long-term stability of MetBaro is in order of 20…50 µBar and resolution a few µBar. MetBaro is small, lightweighed and has low power consumption. It weighs about 50g without wires and controlling FPGA, and consumes 15 mW of power. A similar device has successfully flown in Phoenix mission, where it performed months of measurements on Martian ground. Another device is also part of the Mars Science Laboratory REMS instrument (to be launched in 2011).

With hiccups and bumps: the development of a Rasch-based instrument to measure elementary students' understanding of the nature of science.

Science.gov (United States)

Peoples, Shelagh M; O'Dwyer, Laura M; Shields, Katherine A; Wang, Yang

2013-01-01

This research describes the development process, psychometric analyses and part validation study of a theoretically-grounded Rasch-based instrument, the Nature of Science Instrument-Elementary (NOSI-E). The NOSI-E was designed to measure elementary students' understanding of the Nature of Science (NOS). Evidence is provided for three of the six validity aspects (content, substantive and generalizability) needed to support the construct validity of the NOSI-E. A future article will examine the structural and external validity aspects. Rasch modeling proved especially productive in scale improvement efforts. The instrument, designed for large-scale assessment use, is conceptualized using five construct domains. Data from 741 elementary students were used to pilot the Rasch scale, with continuous improvements made over three successive administrations. The psychometric properties of the NOSI-E instrument are consistent with the basic assumptions of Rasch measurement, namely that the items are well-fitting and invariant. Items from each of the five domains (Empirical, Theory-Laden, Certainty, Inventive, and Socially and Culturally Embedded) are spread along the scale's continuum and appear to overlap well. Most importantly, the scale seems appropriately calibrated and responsive for elementary school-aged children, the target age group. As a result, the NOSI-E should prove beneficial for science education research. As the United States' science education reform efforts move toward students' learning science through engaging in authentic scientific practices (NRC, 2011), it will be important to assess whether this new approach to teaching science is effective. The NOSI-E can be used as one measure of whether this reform effort has an impact.

Saving energy in 1-D : tailoring energy-saving advice using a Rasch-based energy recommender system

NARCIS (Netherlands)

Starke, Alain; Willemsen, Martijn; Snijders, Chris; Ge, Mouhzi; Ricci, Francesco

2015-01-01

Although there are numerous possibilities to save energy, conservation initiatives often do not tailor their content to the consumer. By considering energy conservation as a one-dimensional construct, where different behaviors have different execution difficulties, we have set out a Rasch-based

Differences in MetS marker prevalence between black African and ...

African Journals Online (AJOL)

Multiple linear regression analysis, independent of covariates, showed that the albumin:creatinine ratio is explained only by glucose in Africans. Conclusion: African women, as a group, present with few MetS risk factors, and glucose is associated with renal function risk in Africans. Keywords: MetS, metabolic syndrome, ...

Rasch models suggested the satisfactory psychometric properties of the World Health Organization Quality of Life-Brief among lung cancer patients.

Science.gov (United States)

Lin, Chung-Ying; Yang, Szu-Chun; Lai, Wu-Wei; Su, Wu-Chou; Wang, Jung-Der

2017-03-01

The study examined whether the items of the World Health Organization Quality of Life-Brief questionnaire can assess its four underlying domains (Physical, Psychological, Social, and Environment) in a sample of lung cancer patients. All patients ( n = 1150) were recruited from a medical center in Tainan, and each participant completed the World Health Organization Quality of Life-Brief. Several Rasch rating scale models were used to examine the data-model fit, and Rasch analyses corroborated that each domain of the World Health Organization Quality of Life-Brief could be unidimensional. Although three items were found to have a poor fit, all the other items fit the unidimensionality with ordered thresholds.

Comparison of formula and number-right scoring in undergraduate medical training: a Rasch model analysis.

Science.gov (United States)

Cecilio-Fernandes, Dario; Medema, Harro; Collares, Carlos Fernando; Schuwirth, Lambert; Cohen-Schotanus, Janke; Tio, René A

2017-11-09

Progress testing is an assessment tool used to periodically assess all students at the end-of-curriculum level. Because students cannot know everything, it is important that they recognize their lack of knowledge. For that reason, the formula-scoring method has usually been used. However, where partial knowledge needs to be taken into account, the number-right scoring method is used. Research comparing both methods has yielded conflicting results. As far as we know, in all these studies, Classical Test Theory or Generalizability Theory was used to analyze the data. In contrast to these studies, we will explore the use of the Rasch model to compare both methods. A 2 × 2 crossover design was used in a study where 298 students from four medical schools participated. A sample of 200 previously used questions from the progress tests was selected. The data were analyzed using the Rasch model, which provides fit parameters, reliability coefficients, and response option analysis. The fit parameters were in the optimal interval ranging from 0.50 to 1.50, and the means were around 1.00. The person and item reliability coefficients were higher in the number-right condition than in the formula-scoring condition. The response option analysis showed that the majority of dysfunctional items emerged in the formula-scoring condition. The findings of this study support the use of number-right scoring over formula scoring. Rasch model analyses showed that tests with number-right scoring have better psychometric properties than formula scoring. However, choosing the appropriate scoring method should depend not only on psychometric properties but also on self-directed test-taking strategies and metacognitive skills.

Unified Balance Scale: an activity-based, bed to community, and aetiology-independent measure of balance calibrated with Rasch analysis.

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La Porta, Fabio; Franceschini, Marco; Caselli, Serena; Cavallini, Paola; Susassi, Sonia; Tennant, Alan

2011-04-01

To build a new activity-based, "bed to community", aetiology-independent measure of balance within the neurological rehabilitation setting by merging some existing scales. Balance scales were selected using a conceptual framework and subsequently administered to a convenience sample of adult patients with balance problems due to different neurological aetiologies. Data were then processed using classical psychometric analyses and Rasch analysis in order to construct a new balance measurement tool. The Berg Balance Scale, the Tinetti Scales and the Fullerton Advanced Balance Scale were selected and administered to a sample of patients, giving 302 observations. Classical psychometric analyses (item and scale analysis; confirmatory factor analysis) were undertaken on the pooled 40-item set with confirmation of unidimensionality. The subsequent Rasch analysis allowed the identification of a 27-item set satisfying the Rasch Model's requirements for fundamental measurement, with further confirmation of unidimensionality by post-hoc confirmatory factor analysis. The new scale (Unified Balance Scale) holds proven measurement properties and may be a candidate tool for "bed to community" balance measurement for patients with balance problems within the neuro-rehabilitation setting. Future studies are warranted to explore further its external validity and other clinical properties, as well as to improve its usability.

Development of Rasch-based item banks for the assessment of work performance in patients with musculoskeletal diseases.

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Mueller, Evelyn A; Bengel, Juergen; Wirtz, Markus A

2013-12-01

This study aimed to develop a self-description assessment instrument to measure work performance in patients with musculoskeletal diseases. In terms of the International Classification of Functioning, Disability and Health (ICF), work performance is defined as the degree of meeting the work demands (activities) at the actual workplace (environment). To account for the fact that work performance depends on the work demands of the job, we strived to develop item banks that allow a flexible use of item subgroups depending on the specific work demands of the patients' jobs. Item development included the collection of work tasks from literature and content validation through expert surveys and patient interviews. The resulting 122 items were answered by 621 patients with musculoskeletal diseases. Exploratory factor analysis to ascertain dimensionality and Rasch analysis (partial credit model) for each of the resulting dimensions were performed. Exploratory factor analysis resulted in four dimensions, and subsequent Rasch analysis led to the following item banks: 'impaired productivity' (15 items), 'impaired cognitive performance' (18), 'impaired coping with stress' (13) and 'impaired physical performance' (low physical workload 20 items, high physical workload 10 items). The item banks exhibited person separation indices (reliability) between 0.89 and 0.96. The assessment of work performance adds the activities component to the more commonly employed participation component of the ICF-model. The four item banks can be adapted to specific jobs where necessary without losing comparability of person measures, as the item banks are based on Rasch analysis.

Modern psychometrics for assessing achievement goal orientation: a Rasch analysis.

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Muis, Krista R; Winne, Philip H; Edwards, Ordene V

2009-09-01

A program of research is needed that assesses the psychometric properties of instruments designed to quantify students' achievement goal orientations to clarify inconsistencies across previous studies and to provide a stronger basis for future research. We conducted traditional psychometric and modern Rasch-model analyses of the Achievement Goals Questionnaire (AGQ, Elliot & McGregor, 2001) and the Patterns of Adaptive Learning Scale (PALS, Midgley et al., 2000) to provide an in-depth analysis of the two most popular instruments in educational psychology. For Study 1, 217 undergraduate students enrolled in educational psychology courses participated. Thirty-four were male and 181 were female (two did not respond). Participants completed the AGQ in the context of their educational psychology class. For Study 2, 126 undergraduate students enrolled in educational psychology courses participated. Thirty were male and 95 were female (one did not respond). Participants completed the PALS in the context of their educational psychology class. Traditional psychometric assessments of the AGQ and PALS replicated previous studies. For both, reliability estimates ranged from good to very good for raw subscale scores and fit for the models of goal orientations were good. Based on traditional psychometrics, the AGQ and PALS are valid and reliable indicators of achievement goals. Rasch analyses revealed that estimates of reliability for items were very good but respondent ability estimates varied from poor to good for both the AGQ and PALS. These findings indicate that items validly and reliably reflect a group's aggregate goal orientation, but using either instrument to characterize an individual's goal orientation is hazardous.

Rasch Analysis of Lebanese Nurses’ Responses to the EIS Questionnaire

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Michael Clinton

2014-08-01

Full Text Available This study examined the psychometric characteristics of a 32-item modified version of the Ethical Issues Scale (EIS. Data were collected from 59 registered nurses at the American University of Beirut Medical Centre (AUBMC. Data were analyzed using WINSTEPS Rasch analysis software. The four-category EIS rating scale needs modification for future studies in Lebanon. All EIS scale items need rewording prior to translation into Arabic to avoid confusion among Lebanese nurses. Principal component analysis (PCA of residuals indicated the possible presence of additional dimensions. Additional EIS items are needed to improve targeting.

Cross-cultural validity of the Spanish version of PHQ-9 among pregnant Peruvian women: a Rasch item response theory analysis.

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Zhong, Qiuyue; Gelaye, Bizu; Fann, Jesse R; Sanchez, Sixto E; Williams, Michelle A

2014-04-01

We sought to evaluate the validity of the Spanish language version of the patient health questionnaire-9 (PHQ-9) depression scale in a large sample of pregnant Peruvian women using Rasch item response theory (IRT) approaches. We further sought to examine the appropriateness of the response formats, reliability and potential differential item functioning (DIF) by maternal age, educational attainment and employment status. This cross-sectional study was conducted among 1520 pregnant women in Lima, Peru. A structured interview was used to collect information on demographic characteristics and PHQ-9 items. Data from the PHQ-9 were fitted to the Rasch IRT model and tested for appropriate category ordering, the assumptions of unidimensionality and local independence, item fit, reliability and presence of DIF. The Spanish language version of PHQ-9 demonstrated unidimensionality, local independence, and acceptable fit for the Rasch IRT model. However, we detected disordered response categories for the original four response categories. After collapsing "more than half the days" and "nearly every day", the response categories ordered properly and the PHQ-9 fit the Rasch IRT model. The PHQ-9 had moderate internal consistency (person separation index, PSI=0.72). Additionally, the items of PHQ-9 were free of DIF with regard to age, educational attainment, and employment status. The Spanish language version of the PHQ-9 was shown to have item properties of an effective screening instrument. Collapsing rating scale categories and reconstructing three-point Likert scale for all items improved the fit of the instrument. Future studies are warranted to establish new cutoff scores and criterion validity of the three-point Likert scale response options for the Spanish language version of the PHQ-9. Copyright © 2014 Elsevier B.V. All rights reserved.

Using and Developing Measurement Instruments in Science Education: A Rasch Modeling Approach. Science & Engineering Education Sources

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Liu, Xiufeng

2010-01-01

This book meets a demand in the science education community for a comprehensive and introductory measurement book in science education. It describes measurement instruments reported in refereed science education research journals, and introduces the Rasch modeling approach to developing measurement instruments in common science assessment domains,…

Structural characterization of the stringent response related exopolyphosphatase/guanosine pentaphosphate phosphohydrolase protein family

DEFF Research Database (Denmark)

Kristensen, Ole; Laurberg, Martin; Liljas, Anders

2004-01-01

Exopolyphosphatase/guanosine pentaphosphate phosphohydrolase (PPX/GPPA) enzymes play central roles in the bacterial stringent response induced by starvation. The high-resolution crystal structure of the putative Aquifex aeolicus PPX/GPPA phosphatase from the actin-like ATPase domain superfamily has...

Examination of an eHealth literacy scale and a health literacy scale in a population with moderate to high cardiovascular risk: Rasch analyses.

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Sarah S Richtering

Full Text Available Electronic health (eHealth strategies are evolving making it important to have valid scales to assess eHealth and health literacy. Item response theory methods, such as the Rasch measurement model, are increasingly used for the psychometric evaluation of scales. This paper aims to examine the internal construct validity of an eHealth and health literacy scale using Rasch analysis in a population with moderate to high cardiovascular disease risk.The first 397 participants of the CONNECT study completed the electronic health Literacy Scale (eHEALS and the Health Literacy Questionnaire (HLQ. Overall Rasch model fit as well as five key psychometric properties were analysed: unidimensionality, response thresholds, targeting, differential item functioning and internal consistency.The eHEALS had good overall model fit (χ2 = 54.8, p = 0.06, ordered response thresholds, reasonable targeting and good internal consistency (person separation index (PSI 0.90. It did, however, appear to measure two constructs of eHealth literacy. The HLQ subscales (except subscale 5 did not fit the Rasch model (χ2: 18.18-60.60, p: 0.00-0.58 and had suboptimal targeting for most subscales. Subscales 6 to 9 displayed disordered thresholds indicating participants had difficulty distinguishing between response options. All subscales did, nonetheless, demonstrate moderate to good internal consistency (PSI: 0.62-0.82.Rasch analyses demonstrated that the eHEALS has good measures of internal construct validity although it appears to capture different aspects of eHealth literacy (e.g. using eHealth and understanding eHealth. Whilst further studies are required to confirm this finding, it may be necessary for these constructs of the eHEALS to be scored separately. The nine HLQ subscales were shown to measure a single construct of health literacy. However, participants' scores may not represent their actual level of ability, as distinction between response categories was unclear for

Organizational Culture Influence On Total Productive Maintenance (TPM and Operational Performance Using RASCH Model Analysis

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Mohd Norhasni Mohd Asaad

2014-02-01

Full Text Available Abstract. Market globalization, competitive product and services, high economic crises are the most critical factors that influence the success of the manufacturing companies in global market. Therefore it is critical to the manufacturing companies to be efficient in production and lean tool may used to achieve that.  The most frequently used is the Total Preventive Maintenance (TPM, even though there are many studies have been conducted in relation to the TPM but there is limited research in investigating the effects of the TPM on operational performance. However, the result of the studies was not consistent, where TPM practice may have positive and negative impact on operational performance. Among the reason is the culture of the organization that influenced the implementation of TPM and operational performance. Due to that this study attempts to investigate the influence of organizational culture on the TPM implementation and operational performance.  Rasch model is used in this study due to its ability in interpreting and analyzing the ability of respondents in performing the difficult items. The online questionnaires were distributed to 63 randomly selected automotive companies located at Northern Region of Malaysia.  Results of the study revealed that the organizational culture has influenced on the successful implementation of TPM and operational performance. Therefore by the implementation of TPM in outstanding organizational culture can improve operational performance.   Keyword: Total Preventive Maintenance (TPM, Lean manufacturing, Operational performance, Organizational culture, Rasch modeldoi:10.12695/ajtm.2013.6.2.2How to cite this article:Mohd Asaad, M.N and Yusoff, R.Z. (2013. Organizational Culture Influence On Total Productive Maintenance (TPM and Operational Performance Using RASCH Model Analysis . The Asian Journal of Technology Management 6 (2: 72-81. Print ISSN: 1978-6956; Online ISSN: 2089-791X.  doi:10.12695/ajtm

Rasch Analysis of the Bruininks-Oseretsky Test of Motor Proficiency--Second Edition in Intellectual Disabilities

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Wuang, Yee-Pay; Lin, Yueh-Hsien; Su, Chwen-Yng

2009-01-01

The Bruininks-Oseretsky Test of Motor Proficiency-Second Edition (BOT-2) is widely used to assess motor skills for both clinical and research purposes; however, its validity has not been adequately assessed in intellectual disabilities (ID). This study used partial credit Rasch model to examine the measurement properties of the BOT-2 among 446…

Measuring Math Anxiety (in Spanish) with the Rasch Rating Scale Model.

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Prieto, Gerardo; Delgado, Ana R

2007-01-01

Two successive studies probed the psychometric properties of a Math Anxiety questionnaire (in Spanish) by means of the Rasch Rating Scale Model. Participants were 411 and 216 Spanish adolescents. Convergent validity was examined by correlating the scale with both the Fennema and Sherman Attitude Scale and a math achievement test. The results show that the scores are psychometrically appropriate, and replicate those reported in meta-analyses: medium-sized negative correlations with achievement and with attitudes toward mathematics, as well as moderate sex-related differences (with girls presenting higher anxiety levels than boys).

Using the Mixture Rasch Model to Explore Knowledge Resources Students Invoke in Mathematic and Science Assessments

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Zhang, Danhui; Orrill, Chandra; Campbell, Todd

2015-01-01

The purpose of this study was to investigate whether mixture Rasch models followed by qualitative item-by-item analysis of selected Programme for International Student Assessment (PISA) mathematics and science items offered insight into knowledge students invoke in mathematics and science separately and combined. The researchers administered an…

Synthetic Peptides to Target Stringent Response-Controlled Virulence in a Pseudomonas aeruginosa Murine Cutaneous Infection Model

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Daniel Pletzer

2017-09-01

Full Text Available Microorganisms continuously monitor their surroundings and adaptively respond to environmental cues. One way to cope with various stress-related situations is through the activation of the stringent stress response pathway. In Pseudomonas aeruginosa this pathway is controlled and coordinated by the activity of the RelA and SpoT enzymes that metabolize the small nucleotide secondary messenger molecule (pppGpp. Intracellular ppGpp concentrations are crucial in mediating adaptive responses and virulence. Targeting this cellular stress response has recently been the focus of an alternative approach to fight antibiotic resistant bacteria. Here, we examined the role of the stringent response in the virulence of P. aeruginosa PAO1 and the Liverpool epidemic strain LESB58. A ΔrelA/ΔspoT double mutant showed decreased cytotoxicity toward human epithelial cells, exhibited reduced hemolytic activity, and caused down-regulation of the expression of the alkaline protease aprA gene in stringent response mutants grown on blood agar plates. Promoter fusions of relA or spoT to a bioluminescence reporter gene revealed that both genes were expressed during the formation of cutaneous abscesses in mice. Intriguingly, virulence was attenuated in vivo by the ΔrelA/ΔspoT double mutant, but not the relA mutant nor the ΔrelA/ΔspoT complemented with either gene. Treatment of a cutaneous P. aeruginosa PAO1 infection with anti-biofilm peptides increased animal welfare, decreased dermonecrotic lesion sizes, and reduced bacterial numbers recovered from abscesses, resembling the phenotype of the ΔrelA/ΔspoT infection. It was previously demonstrated by our lab that ppGpp could be targeted by synthetic peptides; here we demonstrated that spoT promoter activity was suppressed during cutaneous abscess formation by treatment with peptides DJK-5 and 1018, and that a peptide-treated relA complemented stringent response double mutant strain exhibited reduced peptide

Factor and Rasch analysis of the Fonseca anamnestic index for the diagnosis of myogenous temporomandibular disorder.

Science.gov (United States)

Rodrigues-Bigaton, Delaine; de Castro, Ester M; Pires, Paulo F

Rasch analysis has been used in recent studies to test the psychometric properties of a questionnaire. The conditions for use of the Rasch model are one-dimensionality (assessed via prior factor analysis) and local independence (the probability of getting a particular item right or wrong should not be conditioned upon success or failure in another). To evaluate the dimensionality and the psychometric properties of the Fonseca anamnestic index (FAI), such as the fit of the data to the model, the degree of difficulty of the items, and the ability to respond in patients with myogenous temporomandibular disorder (TMD). The sample consisted of 94 women with myogenous TMD, diagnosed by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), who answered the FAI. For the factor analysis, we applied the Kaiser-Meyer-Olkin test, Bartlett's sphericity, Spearman's correlation, and the determinant of the correlation matrix. For extraction of the factors/dimensions, an eigenvalue >1.0 was used, followed by oblique oblimin rotation. The Rasch analysis was conducted on the dimension that showed the highest proportion of variance explained. Adequate sample "n" and FAI multidimensionality were observed. Dimension 1 (primary) consisted of items 1, 2, 3, 6, and 7. All items of dimension 1 showed adequate fit to the model, being observed according to the degree of difficulty (from most difficult to easiest), respectively, items 2, 1, 3, 6, and 7. The FAI presented multidimensionality with its main dimension consisting of five reliable items with adequate fit to the composition of its structure. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

Diagnosis of students' ability in a statistical course based on Rasch probabilistic outcome

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Mahmud, Zamalia; Ramli, Wan Syahira Wan; Sapri, Shamsiah; Ahmad, Sanizah

2017-06-01

Measuring students' ability and performance are important in assessing how well students have learned and mastered the statistical courses. Any improvement in learning will depend on the student's approaches to learning, which are relevant to some factors of learning, namely assessment methods carrying out tasks consisting of quizzes, tests, assignment and final examination. This study has attempted an alternative approach to measure students' ability in an undergraduate statistical course based on the Rasch probabilistic model. Firstly, this study aims to explore the learning outcome patterns of students in a statistics course (Applied Probability and Statistics) based on an Entrance-Exit survey. This is followed by investigating students' perceived learning ability based on four Course Learning Outcomes (CLOs) and students' actual learning ability based on their final examination scores. Rasch analysis revealed that students perceived themselves as lacking the ability to understand about 95% of the statistics concepts at the beginning of the class but eventually they had a good understanding at the end of the 14 weeks class. In terms of students' performance in their final examination, their ability in understanding the topics varies at different probability values given the ability of the students and difficulty of the questions. Majority found the probability and counting rules topic to be the most difficult to learn.

Measuring Engagement in Later Life Activities: Rasch-Based Scenario Scales for Work, Caregiving, Informal Helping, and Volunteering

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Ludlow, Larry H.; Matz-Costa, Christina; Johnson, Clair; Brown, Melissa; Besen, Elyssa; James, Jacquelyn B.

2014-01-01

The development of Rasch-based "comparative engagement scenarios" based on Guttman's facet theory and sentence mapping procedures is described. The scenario scales measuring engagement in work, caregiving, informal helping, and volunteering illuminate the lived experiences of role involvement among older adults and offer multiple…

Ten Year Study of the Stringently Defined Otitis Prone Child in Rochester, NY

Science.gov (United States)

Pichichero, Michael E.

2016-01-01

This review summarizes a prospective, longitudinal 10-year study in Rochester NY with virtually every clinically diagnosed acute otitis media (AOM) confirmed by bacterial culture of middle ear fluid. Children experiencing 3 episodes within 6 months or 4 episodes in 12 months were considered stringently-defined otitis prone (sOP). We found stringent diagnosis compared with clinical diagnosis reduced the frequency of children meeting the OP definition from 27% to 6% resulting in 14.8% and 2.4% receiving tympanostomy tubes, respectively. Significantly more often RSV infection led to AOM in sOP than non-otitis prone (NOP) children that correlated with diminished total RSV-specific serum IgG. sOP children produced low levels of antibody to Streptococcus pneumoniae and Haemophilus influenzae candidate vaccine protein antigens and to routine pediatric vaccines. sOP children generated significantly fewer memory B cells, functional and memory T cells to otopathogens following NP colonization and AOM than NOP children and they had defects in antigen presenting cells. PMID:27273691

Item and response-category functioning of the Persian version of the KIDSCREEN-27: Rasch partial credit model

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Jafari Peyman

2012-10-01

Full Text Available Abstract Background The purpose of the study was to determine whether the Persian version of the KIDSCREEN-27 has the optimal number of response category to measure health-related quality of life (HRQoL in children and adolescents. Moreover, we aimed to determine if all the items contributed adequately to their own domain. Findings The Persian version of the KIDSCREEN-27 was completed by 1083 school children and 1070 of their parents. The Rasch partial credit model (PCM was used to investigate item statistics and ordering of response categories. The PCM showed that no item was misfitting. The PCM also revealed that, successive response categories for all items were located in the expected order except for category 1 in self- and proxy-reports. Conclusions Although Rasch analysis confirms that all the items belong to their own underlying construct, response categories should be reorganized and evaluated in further studies, especially in children with chronic conditions.

Assessing Pre-Service Physics Teachers’ Energy Literacy: An Application of Rasch measurement

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Yusup, M.; Setiawan, A.; Rustaman, N. Y.; Kaniawati, I.

2017-09-01

This paper aims to present a summary of pre-service physics teachers’ responses on energy literacy assessment. A total of 123 pre-service physics teacher in first through third year of education participated. Data were analyzed using Rasch modeling. Research findings indicate that pre-service physics teachers show their low self-system toward energy conservation. They were also still lack of metacognitive and cognitive competencies. These finding provide information for the future development of curriculum, teaching and learning that can improve pre-service physics teachers’ energy literacy.

Stringent homology-based prediction of H. sapiens-M. tuberculosis H37Rv protein-protein interactions.

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Zhou, Hufeng; Gao, Shangzhi; Nguyen, Nam Ninh; Fan, Mengyuan; Jin, Jingjing; Liu, Bing; Zhao, Liang; Xiong, Geng; Tan, Min; Li, Shijun; Wong, Limsoon

2014-04-08

H. sapiens-M. tuberculosis H37Rv protein-protein interaction (PPI) data are essential for understanding the infection mechanism of the formidable pathogen M. tuberculosis H37Rv. Computational prediction is an important strategy to fill the gap in experimental H. sapiens-M. tuberculosis H37Rv PPI data. Homology-based prediction is frequently used in predicting both intra-species and inter-species PPIs. However, some limitations are not properly resolved in several published works that predict eukaryote-prokaryote inter-species PPIs using intra-species template PPIs. We develop a stringent homology-based prediction approach by taking into account (i) differences between eukaryotic and prokaryotic proteins and (ii) differences between inter-species and intra-species PPI interfaces. We compare our stringent homology-based approach to a conventional homology-based approach for predicting host-pathogen PPIs, based on cellular compartment distribution analysis, disease gene list enrichment analysis, pathway enrichment analysis and functional category enrichment analysis. These analyses support the validity of our prediction result, and clearly show that our approach has better performance in predicting H. sapiens-M. tuberculosis H37Rv PPIs. Using our stringent homology-based approach, we have predicted a set of highly plausible H. sapiens-M. tuberculosis H37Rv PPIs which might be useful for many of related studies. Based on our analysis of the H. sapiens-M. tuberculosis H37Rv PPI network predicted by our stringent homology-based approach, we have discovered several interesting properties which are reported here for the first time. We find that both host proteins and pathogen proteins involved in the host-pathogen PPIs tend to be hubs in their own intra-species PPI network. Also, both host and pathogen proteins involved in host-pathogen PPIs tend to have longer primary sequence, tend to have more domains, tend to be more hydrophilic, etc. And the protein domains from both

Spinal Cord Independence Measure, version III: applicability to the UK spinal cord injured population.

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Glass, Clive A; Tesio, Luigi; Itzkovich, Malka; Soni, Bakul M; Silva, Pedro; Mecci, Munawar; Chadwick, Raymond; el Masry, Waghi; Osman, Aheed; Savic, Gordana; Gardner, Brian; Bergström, Ebba; Catz, Amiram

2009-09-01

To examine the validity, reliability and usefulness of the Spinal Cord Independence Measure for the UK spinal cord injury population. Multi-centre cohort study. Four UK regional spinal cord injury centres. Eighty-six people with spinal cord injury. Spinal Cord Independence Measure and Functional Independence Measure on admission analysed using inferential statistics, and Rasch analysis of Spinal Cord Independence Measure. Internal consistency, inter-rater reliability, discriminant validity; Spinal Cord Independence Measure subscale match between distribution of item difficulty and patient ability measurements; reliability of patient ability measures; fit of data to Rasch model; unidimensionality of subscales; hierarchical ordering of categories within items; differential item functioning across patient groups. Scale reliability (kappa coefficients range 0.491-0.835; (p Spinal Cord Independence Measure subscales compatible with stringent Rasch requirements; mean infit indices high; distinct strata of abilities identified; most thresholds ordered; item hierarchy stable across clinical groups and centres. Misfit and differences in item hierarchy identified. Difficulties assessing central cord injuries highlighted. Conventional statistical and Rasch analyses justify the use of the Spinal Cord Independence Measure in clinical practice and research in the UK. Cross-cultural validity may be further improved.

Sensitivity of Mantel Haenszel Model and Rasch Model as Viewed From Sample Size

OpenAIRE

ALWI, IDRUS

2011-01-01

The aims of this research is to study the sensitivity comparison of Mantel Haenszel and Rasch Model for detection differential item functioning, observed from the sample size. These two differential item functioning (DIF) methods were compared using simulate binary item respon data sets of varying sample size,  200 and 400 examinees were used in the analyses, a detection method of differential item functioning (DIF) based on gender difference. These test conditions were replication 4 tim...

The Stringent Response Induced by Phosphate Limitation Promotes Purine Salvage in Agrobacterium fabrum.

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Sivapragasam, Smitha; Deochand, Dinesh K; Meariman, Jacob K; Grove, Anne

2017-10-31

Agrobacterium fabrum induces tumor growth in susceptible plant species. The upregulation of virulence genes that occurs when the bacterium senses plant-derived compounds is enhanced by acidic pH and limiting inorganic phosphate. Nutrient starvation may also trigger the stringent response, and purine salvage is among the pathways expected to be favored under such conditions. We show here that phosphate limitation induces the stringent response, as evidenced by production of (p)ppGpp, and that the xdhCSML operon encoding the purine salvage enzyme xanthine dehydrogenase is upregulated ∼15-fold. The xdhCSML operon is under control of the TetR family transcription factor XdhR; direct binding of ppGpp to XdhR attenuates DNA binding, and the enhanced xdhCSML expression correlates with increased cellular levels of (p)ppGpp. Xanthine dehydrogenase may also divert purines away from salvage pathways to form urate, the ligand for the transcription factor PecS, which in the plant pathogen Dickeya dadantii is a key regulator of virulence gene expression. However, urate levels remain low under conditions that produce increased levels of xdhCSML expression, and neither acidic pH nor limiting phosphate results in induction of genes under control of PecS. Instead, expression of such genes is induced only by externally supplemented urate. Taken together, our data indicate that purine salvage is favored during the stringent response induced by phosphate starvation, suggesting that control of this pathway may constitute a novel approach to modulating virulence. Because bacterial purine catabolism appears to be unaffected, as evidenced by the absence of urate accumulation, we further propose that the PecS regulon is induced by only host-derived urate.

Improving the measurement of health-related quality of life in adolescent with idiopathic scoliosis: the SRS-7, a Rasch-developed short form of the SRS-22 questionnaire.

Science.gov (United States)

Caronni, Antonio; Zaina, Fabio; Negrini, Stefano

2014-04-01

Scoliosis Research Society-22 (SRS-22) questionnaire was developed to evaluate health-related quality of life (HRQL) in adolescent idiopathic scoliosis (AIS) patients. Rasch analysis (RA) is a statistical procedure which turns questionnaire ordinal scores into interval measures. Measures from Rasch-compatible questionnaires can be used, similar to body temperature or blood pressure, to quantify disease severity progression and treatment efficacy. Purpose of the current work is to present Rasch analysis (RA) of the SRS-22 questionnaire and to develop an SRS-22 Rasch-approved short form. 300 SRS-22 were randomly collected from 2447 consecutive IS adolescents at their first evaluation (229 females; 13.9 ± 1.9 years; 26.9 ± 14.7 Cobb°) in a scoliosis outpatient clinic. RA showed both disordered thresholds and overall misfit of the SRS-22. Sixteen items were re-scored and two misfitting items (6 and 14) removed to obtain a Rasch-compatible questionnaire. Participants HRQL measured too high with the rearranged questionnaire, indicating a severe SRS-22 ceiling effect. RA also highlighted SRS-22 multidimensionality, with pain/function not merging with self-image/mental health items. Item 3 showed differential item functioning (DIF) for both curve and hump amplitude. A 7-item questionnaire (SRS-7) was prepared by selecting single items from the original SRS-22. SRS-7 showed fit to the model, unidimensionality and no DIF. Compared with the SRS-22, the short form scale shows better targeting of the participants' population. RA shows that SRS-22 has poor clinimetric properties; moreover, when used with AIS at first evaluation, SRS-22 is affected by a severe ceiling effect. SRS-7, an SRS-22 7-item short form questionnaire, provides an HRQL interval measure better tailored to these participants. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identifying potential misfit items in cognitive process of learning engineering mathematics based on Rasch model

International Nuclear Information System (INIS)

Ataei, Sh; Mahmud, Z; Khalid, M N

2014-01-01

The students learning outcomes clarify what students should know and be able to demonstrate after completing their course. So, one of the issues on the process of teaching and learning is how to assess students' learning. This paper describes an application of the dichotomous Rasch measurement model in measuring the cognitive process of engineering students' learning of mathematics. This study provides insights into the perspective of 54 engineering students' cognitive ability in learning Calculus III based on Bloom's Taxonomy on 31 items. The results denote that some of the examination questions are either too difficult or too easy for the majority of the students. This analysis yields FIT statistics which are able to identify if there is data departure from the Rasch theoretical model. The study has identified some potential misfit items based on the measurement of ZSTD where the removal misfit item was accomplished based on the MNSQ outfit of above 1.3 or less than 0.7 logit. Therefore, it is recommended that these items be reviewed or revised to better match the range of students' ability in the respective course.

Rasch Measurement of Collaborative Problem Solving in an Online Environment.

Science.gov (United States)

Harding, Susan-Marie E; Griffin, Patrick E

2016-01-01

This paper describes an approach to the assessment of human to human collaborative problem solving using a set of online interactive tasks completed by student dyads. Within the dyad, roles were nominated as either A or B and students selected their own roles. The question as to whether role selection affected individual student performance measures is addressed. Process stream data was captured from 3402 students in six countries who explored the problem space by clicking, dragging the mouse, moving the cursor and collaborating with their partner through a chat box window. Process stream data were explored to identify behavioural indicators that represented elements of a conceptual framework. These indicative behaviours were coded into a series of dichotomous items. These items represented actions and chats performed by students. The frequency of occurrence was used as a proxy measure of item difficulty. Then given a measure of item difficulty, student ability could be estimated using the difficulty estimates of the range of items demonstrated by the student. The Rasch simple logistic model was used to review the indicators to identify those that were consistent with the assumptions of the model and were invariant across national samples, language, curriculum and age of the student. The data were analysed using a one and two dimension, one parameter model. Rasch separation reliability, fit to the model, distribution of students and items on the underpinning construct, estimates for each country and the effect of role differences are reported. This study provides evidence that collaborative problem solving can be assessed in an online environment involving human to human interaction using behavioural indicators shown to have a consistent relationship between the estimate of student ability, and the probability of demonstrating the behaviour.

Stringent or nonstringent complete remission and prognosis in acute myeloid leukemia

DEFF Research Database (Denmark)

Øvlisen, Andreas K; Oest, Anders; Bendtsen, Mette D

2018-01-01

Stringent complete remission (sCR) of acute myeloid leukemia is defined as normal hematopoiesis after therapy. Less sCR, including non-sCR, was introduced as insufficient blood platelet, neutrophil, or erythrocyte recovery. These latter characteristics were defined retrospectively as postremission...... transfusion dependency and were suggested to be of prognostic value. In the present report, we evaluated the prognostic impact of achieving sCR and non-sCR in the Danish National Acute Leukaemia Registry, including 769 patients registered with classical CR (ie,

Developing a Measure of Therapist Adherence to Contingency Management: An Application of the Many-Facet Rasch Model

Science.gov (United States)

Chapman, Jason E.; Sheidow, Ashli J.; Henggeler, Scott W.; Halliday-Boykins, Colleen A.; Cunningham, Phillippe B.

2008-01-01

A unique application of the Many-Facet Rasch Model (MFRM) is introduced as the preferred method for evaluating the psychometric properties of a measure of therapist adherence to Contingency Management (CM) treatment of adolescent substance use. The utility of psychometric methods based in Classical Test Theory was limited by complexities of the…

Inter-regional metric disadvantages when comparing countries’ happiness on a global scale. A Rasch based consequential validity analysis

Directory of Open Access Journals (Sweden)

Diego Fernando Rojas-Gualdrón

2017-07-01

Full Text Available Measurement confounding due to socioeconomic differences between world regions may bias the estimations of countries’ happiness and global inequality. Potential implications of this bias have not been researched. In this study, the consequential validity of the Happy Planet Index, 2012 as an indicator of global inequality is evaluated from the Rasch measurement perspective. Differential Item Functioning by world region and bias in the estimated magnitude of inequalities were analyzed. The recalculated measure showed a good fit to Rasch model assumptions. The original index underestimated relative inequalities between world regions by 20%. DIF had no effect on relative measures but affected absolute measures by overestimating world average happiness and underestimating its variance. These findings suggest measurement confounding by unmeasured characteristics. Metric disadvantages must be adjusted to make fair comparisons. Public policy decisions based on biased estimations could have relevant negative consequences on people’s health and well-being by not focusing efforts on real vulnerable populations.

Emotional vitality in caregivers: application of Rasch Measurement Theory with secondary data to development and test a new measure.

Science.gov (United States)

Barbic, Skye P; Bartlett, Susan J; Mayo, Nancy E

2015-07-01

To describe the practical steps in identifying items and evaluating scoring strategies for a new measure of emotional vitality in informal caregivers of individuals who have experienced a significant health event. The psychometric properties of responses to selected items from validated health-related quality of life and other psychosocial questionnaires administered four times over a one-year period were evaluated using Rasch Measurement Theory. Community. A total of 409 individuals providing informal care at home to older adults who had experienced a recent stroke. Rasch Measurement Theory was used to test the ordering of response option thresholds, fit, spread of the item locations, residual correlations, person separation index, and stability across time. Based on a theoretical framework developed in earlier work, we identified 22 candidate items from a pool of relevant psychosocial measures available. Of these, additional evaluation resulted in 19 items that could be used to assess the five core domains. The overall model fit was reasonable (χ(2) = 202.26, DF = 117, p = 0.06), stable across time, with borderline evidence of multidimensionality (10%). Items and people covered a continuum ranging from -3.7 to +2.7 logits, reflecting coverage of the measurement continuum, with a person separation index of 0.85. Mean fit of caregivers was lower than expected (-1.31 ±1.10 logits). Established methods from the Rasch Measurement Theory were applied to develop a prototype measure of emotional vitality that is acceptable, reliable, and can be used to obtain an interval level score for use in future research and clinical settings. © The Author(s) 2014.

Validation of the Danish version of the McGill Ingestive Skills Assessment using classical test theory and the Rasch model

DEFF Research Database (Denmark)

Hansen, Tina; Lambert, Heather C; Faber, Jens

2012-01-01

Purpose: The study aimed to validate the Danish version of the Canadian the "McGill Ingestive Skills Assessment" (MISA-DK) for measuring dysphagia in frail elders. Method: One-hundred and ten consecutive older medical patients were recruited to the study. Reliability was assessed by internal...... consistency (Chronbach's alpha). External construct validity (convergent and known-groups validity) was evaluated against theoretical constructs assessing the complex concept of ingestive skills. Internal construct validity was tested using Rasch analysis. Results: High internal consistency reliability...... with Chronbach's alpha of 0.77-0.95 was evident. External construct validity was supported by expected high correlations with most of the constructs related to ingestive skills (r(s)¿=¿0.53 to r(s)¿=¿0.66). The MISA-DK discriminated significantly between known-groups. Fit to the Rasch model (x(2) (df)¿=¿12 (12...

An application of dichotomous and polytomous Rasch models for scoring energy insecurity

International Nuclear Information System (INIS)

Murray, Anthony G.; Mills, Bradford F.

2012-01-01

Household food security in the United States has been extensively researched and a number of indexes have been generated. However, household energy security has been largely ignored even though low-income households spend almost equal income shares on food and energy. This paper uses Rasch models and household responses to energy security questions in the 2005 Residential Energy Consumption Survey to generate an energy insecurity index that is consistent with those found in the food insecurity literature. The analysis yields several important findings for the generation of policy relevant household energy insecurity indexes. Questions that indicate reduction of basic expenditures, such as food, clothing, and shelter, are easiest for households to affirm implying low exposure to energy insecurity. Conversely, questions that concern households leaving the residence due to extreme temperatures consistently imply high exposure to energy insecurity. Households that score in the top decile of the energy insecurity index are more likely to be headed by single-females, be younger, and have a Black household head. Rasch models also identify flaws within survey. Particularly, the scope of the questions is quite broad and a refinement of the survey questions to focus on specific attributes of energy insecurity would likely improve future energy security indexes. - Highlights: ► A novel household energy insecurity index is generated for low-income U.S. families. ► Severely energy insecure households have unique characteristics. ► Energy insecure households are more likely to participate in LIHEAP. ► RECS survey questions should be modified for an improved energy insecurity index.

Using the Rasch measurement model to design a report writing assessment instrument.

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Carlson, Wayne R

2013-01-01

This paper describes how the Rasch measurement model was used to develop an assessment instrument designed to measure student ability to write law enforcement incident and investigative reports. The ability to write reports is a requirement of all law enforcement recruits in the state of Michigan and is a part of the state's mandatory basic training curriculum, which is promulgated by the Michigan Commission on Law Enforcement Standards (MCOLES). Recently, MCOLES conducted research to modernize its training and testing in the area of report writing. A structured validation process was used, which included: a) an examination of the job tasks of a patrol officer, b) input from content experts, c) a review of the professional research, and d) the creation of an instrument to measure student competency. The Rasch model addressed several measurement principles that were central to construct validity, which were particularly useful for assessing student performances. Based on the results of the report writing validation project, the state established a legitimate connectivity between the report writing standard and the essential job functions of a patrol officer in Michigan. The project also produced an authentic instrument for measuring minimum levels of report writing competency, which generated results that are valid for inferences of student ability. Ultimately, the state of Michigan must ensure the safety of its citizens by licensing only those patrol officers who possess a minimum level of core competency. Maintaining the validity and reliability of both the training and testing processes can ensure that the system for producing such candidates functions as intended.

Controlling response dependence in the measurement of change using the Rasch model.

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Andrich, David

2017-01-01

The advantages of using person location estimates from the Rasch model over raw scores for the measurement of change using a common test include the linearization of scores and the automatic handling of statistical properties of repeated measurements. However, the application of the model requires that the responses to the items are statistically independent in the sense that the specific responses to the items on the first time of testing do not affect the responses at a second time. This requirement implies that the responses to the items at both times of assessment are governed only by the invariant location parameters of the items at the two times of testing and the location parameters of each person each time. A specific form of dependence that is pertinent when the same items are used is when the observed response to an item at the second time of testing is affected by the response to the same item at the first time, a form of dependence which has been referred to as response dependence. This paper presents the logic of applying the Rasch model to quantify, control and remove the effect of response dependence in the measurement of change when the same items are used on two occasions. The logic is illustrated with four sets of simulation studies with dichotomous items and with a small example of real data. It is shown that the presence of response dependence can reduce the evidence of change, a reduction which may impact interpretations at the individual, research, and policy levels.

Rasch Analyses of Very Low Food Security among Households and Children in the Three City Study.

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Moffitt, Robert A; Ribar, David C

2016-04-01

The longitudinal Three City Study of low-income families with children measures food hardships using fewer questions and some different questions from the standard U.S. instrument for measuring food security, the Household Food Security Survey Module (HFSSM) in the Current Population Survey (CPS). We utilize a Rasch measurement model to identify thresholds of very low food security among households and very low food security among children in the Three City Study that are comparable to thresholds from the HFSSM. We also use the Three City Study to empirically investigate the determinants of food insecurity and of these specific food insecurity outcomes, estimating a multivariate behavioral Rasch model that is adapted to address longitudinal data. The estimation results indicate that participation in the Supplemental Nutrition Assistance Program and the Temporary Assistance for Needy Families program reduce food insecurity, while poverty and disability among caregivers increase it. Besides its longitudinal structure, the Three City Study measures many more characteristics about households than the CPS. Our estimates reveal that financial assistance through social networks and a household's own financial assets reduce food insecurity, while its outstanding loans increase insecurity.

Rasch Analyses of Very Low Food Security among Households and Children in the Three City Study*

Science.gov (United States)

Moffitt, Robert A.; Ribar, David C.

2017-01-01

The longitudinal Three City Study of low-income families with children measures food hardships using fewer questions and some different questions from the standard U.S. instrument for measuring food security, the Household Food Security Survey Module (HFSSM) in the Current Population Survey (CPS). We utilize a Rasch measurement model to identify thresholds of very low food security among households and very low food security among children in the Three City Study that are comparable to thresholds from the HFSSM. We also use the Three City Study to empirically investigate the determinants of food insecurity and of these specific food insecurity outcomes, estimating a multivariate behavioral Rasch model that is adapted to address longitudinal data. The estimation results indicate that participation in the Supplemental Nutrition Assistance Program and the Temporary Assistance for Needy Families program reduce food insecurity, while poverty and disability among caregivers increase it. Besides its longitudinal structure, the Three City Study measures many more characteristics about households than the CPS. Our estimates reveal that financial assistance through social networks and a household's own financial assets reduce food insecurity, while its outstanding loans increase insecurity. PMID:29187764

Development and validation of the Brazilian version of the Attitudes to Aging Questionnaire (AAQ: An example of merging classical psychometric theory and the Rasch measurement model

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Trentini Clarissa M

2008-01-01

Full Text Available Abstract Background Aging has determined a demographic shift in the world, which is considered a major societal achievement, and a challenge. Aging is primarily a subjective experience, shaped by factors such as gender and culture. There is a lack of instruments to assess attitudes to aging adequately. In addition, there is no instrument developed or validated in developing region contexts, so that the particularities of ageing in these areas are not included in the measures available. This paper aims to develop and validate a reliable attitude to aging instrument by combining classical psychometric approach and Rasch analysis. Methods Pilot study and field trial are described in details. Statistical analysis included classic psychometric theory (EFA and CFA and Rasch measurement model. The latter was applied to examine unidimensionality, response scale and item fit. Results Sample was composed of 424 Brazilian old adults, which was compared to an international sample (n = 5238. The final instrument shows excellent psychometric performance (discriminant validity, confirmatory factor analysis and Rasch fit statistics. Rasch analysis indicated that modifications in the response scale and item deletions improved the initial solution derived from the classic approach. Conclusion The combination of classic and modern psychometric theories in a complementary way is fruitful for development and validation of instruments. The construction of a reliable Brazilian Attitudes to Aging Questionnaire is important for assessing cultural specificities of aging in a transcultural perspective and can be applied in international cross-cultural investigations running less risk of cultural bias.

Clinical usefulness of the clock drawing test applying rasch analysis in predicting of cognitive impairment.

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Yoo, Doo Han; Lee, Jae Shin

2016-07-01

[Purpose] This study examined the clinical usefulness of the clock drawing test applying Rasch analysis for predicting the level of cognitive impairment. [Subjects and Methods] A total of 187 stroke patients with cognitive impairment were enrolled in this study. The 187 patients were evaluated by the clock drawing test developed through Rasch analysis along with the mini-mental state examination of cognitive evaluation tool. An analysis of the variance was performed to examine the significance of the mini-mental state examination and the clock drawing test according to the general characteristics of the subjects. Receiver operating characteristic analysis was performed to determine the cutoff point for cognitive impairment and to calculate the sensitivity and specificity values. [Results] The results of comparison of the clock drawing test with the mini-mental state showed significant differences in according to gender, age, education, and affected side. A total CDT of 10.5, which was selected as the cutoff point to identify cognitive impairement, showed a sensitivity, specificity, Youden index, positive predictive, and negative predicive values of 86.4%, 91.5%, 0.8, 95%, and 88.2%. [Conclusion] The clock drawing test is believed to be useful in assessments and interventions based on its excellent ability to identify cognitive disorders.

Rasch analysis of the 23-item version of the Roland Morris Disability Questionnaire

DEFF Research Database (Denmark)

Kent, Peter; Grotle, Margreth; Dunn, Kate M

2015-01-01

OBJECTIVE: To determine the psychometric properties of the 23-item version of the Roland Morris Disability Questionnaire (RMDQ-23) and to quantify their stability across 2 cultures/languages and 2 types of care-settings. METHODS: Rasch analysis of data from 1,000 patients with low back pain from...... clinical characteristics (such as age, gender, pain intensity, pain duration and care setting), depending on the country. CONCLUSION: As similar results have been found for the RMDQ-24, we believe it is timely to reconsider whether: (i) the RMDQ should be reconstructed using an item-response theory...

Gezondheidsrisico's in verband met het werken met Pentachloorfenol : een onderzoek

NARCIS (Netherlands)

Geuskens, R.B.M.; Nossent, S.M.; Koëter, H.B.W.M.; Dreef-van der Meulen, H.C.; Stijkel, A.; Zielhuis, R.l.

1989-01-01

De gezondheidsrisico's i.v.m. het werken met pentachloorfenol (PCP) wordt geevalueerd. Het gebruik van PCP in Nederlandse arbeidssituaties neemt sterk af en is beperkt tot de formulering van emeltenkorrels en de, met name preventieve, houtverduurzaming. De totale risicopopulatie is niet omvangrijk

Protocol: validation of the INCODE barometer to measure the innovation compe-tence through the Rasch Measurement Theory

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Lidia Sanchez

2017-06-01

Full Text Available This communication presents a protocol in order to show the different phases that must be followed in order to validate the INCODE barometer, which is used to measure the innovation competence, with Rasch Measurement Theory. Five phases are stated: dimensionality analysis, individual reliability and validity analysis of ítems and persons, global reliability and validity analysis, and cathegory analysis.

Flight Hardware Packaging Design for Stringent EMC Radiated Emission Requirements

Science.gov (United States)

Lortz, Charlene L.; Huang, Chi-Chien N.; Ravich, Joshua A.; Steiner, Carl N.

2013-01-01

This packaging design approach can help heritage hardware meet a flight project's stringent EMC radiated emissions requirement. The approach requires only minor modifications to a hardware's chassis and mainly concentrates on its connector interfaces. The solution is to raise the surface area where the connector is mounted by a few millimeters using a pedestal, and then wrapping with conductive tape from the cable backshell down to the surface-mounted connector. This design approach has been applied to JPL flight project subsystems. The EMC radiated emissions requirements for flight projects can vary from benign to mission critical. If the project's EMC requirements are stringent, the best approach to meet EMC requirements would be to design an EMC control program for the project early on and implement EMC design techniques starting with the circuit board layout. This is the ideal scenario for hardware that is built from scratch. Implementation of EMC radiated emissions mitigation techniques can mature as the design progresses, with minimal impact to the design cycle. The real challenge exists for hardware that is planned to be flown following a built-to-print approach, in which heritage hardware from a past project with a different set of requirements is expected to perform satisfactorily for a new project. With acceptance of heritage, the design would already be established (circuit board layout and components have already been pre-determined), and hence any radiated emissions mitigation techniques would only be applicable at the packaging level. The key is to take a heritage design with its known radiated emissions spectrum and repackage, or modify its chassis design so that it would have a better chance of meeting the new project s radiated emissions requirements.

Use of Rasch Analysis to Evaluate and Refine the Community Balance and Mobility Scale for Use in Ambulatory Community-Dwelling Adults Following Stroke

Science.gov (United States)

Pollock, Courtney L.; Brouwer, Brenda; Garland, S. Jayne

2016-01-01

Background The Community Balance and Mobility Scale (CB&M) is increasingly used to evaluate walking balance following stroke. Objective This study applied Rasch analysis to evaluate and refine the CB&M for use in ambulatory community-dwelling adults following stroke. Methods The CB&M content was linked to task demands and motor skill classifications. Rasch analysis was used to evaluate internal construct validity (structural validity) and refine the CB&M for use with ambulatory community-dwelling adults following stroke. The CB&M data were collected at 3 time points: at discharge from inpatient rehabilitation and at 6 and 12 months postdischarge (N=238). Rasch analysis evaluated scale dimensionality, item and person fit, item response bias, scoring hierarchy, and targeting. Disordered scoring hierarchy was resolved by collapsing scoring categories. Highly correlated and “misfitting” items were removed. Sensitivity to change was evaluated with standardized response means (SRMs) and one-way repeated-measures analysis of variance. Results The CB&M was primarily linked to closed body transport task demands. Significant item-trait interaction, disordered scoring hierarchies, and multidimensionality were found. Scoring categories were collapsed in 15/19 items, and 5 misfitting items were removed. The resulting stroke-specific 14-item unidimensional CB&M (CB&MStroke) fit Rasch model expectations, with no item response bias, acceptable targeting (13% floor effects and 0% ceiling effects), and moderate-to-strong sensitivity to change at 6 months postdischarge (SRM=0.63; 95% confidence interval=−1.523, −0.142) and 12 months postdischarge (SRM=0.73; 95% confidence interval=−2.318, −0.760). Limitations Findings are limited to a modest-sized sample of individuals with mild-to-moderate balance impairment following stroke. Conclusions The CB&MStroke shows promise as a clinical scale for measuring change in walking balance in ambulatory community-dwelling adults

Improving Measurement of Trait Competitiveness: A Rasch Analysis of the Revised Competitiveness Index With Samples From New Zealand and US University Students.

Science.gov (United States)

Krägeloh, Christian U; Medvedev, Oleg N; Hill, Erin M; Webster, Craig S; Booth, Roger J; Henning, Marcus A

2018-01-01

Measuring competitiveness is necessary to fully understand variables affecting student learning. The 14-item Revised Competitiveness Index has become a widely used measure to assess trait competitiveness. The current study reports on a Rasch analysis to investigate the psychometric properties of the Revised Competitiveness Index and to improve its precision for international comparisons. Students were recruited from medical studies at a university in New Zealand, undergraduate health sciences courses at another New Zealand university, and a psychology undergraduate class at a university in the United States. Rasch model estimate parameters were affected by local dependency and item misfit. Best fit to the Rasch model (χ 2 (20) = 15.86, p = .73, person separation index = .95) was obtained for the Enjoyment of Competition subscale after combining locally dependent items into a subtest and discarding the highly misfitting Item 9. The only modifications required to obtain a suitable fit (χ 2 (25) = 25.81, p = .42, person separation index = .77) for the Contentiousness subscale were a subtest to combine two locally dependent items and splitting this subtest by country to deal with differential item functioning. The results support reliability and internal construct validity of the modified Revised Competitiveness Index. Precision of the measure may be enhanced using the ordinal-to-interval conversion algorithms presented here, allowing the use of parametric statistics without breaking fundamental statistical assumptions.

A Multi-Marker Genetic Association Test Based on the Rasch Model Applied to Alzheimer's Disease.

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Wenjia Wang

Full Text Available Results from Genome-Wide Association Studies (GWAS have shown that the genetic basis of complex traits often include many genetic variants with small to moderate effects whose identification remains a challenging problem. In this context multi-marker analysis at the gene and pathway level can complement traditional point-wise approaches that treat the genetic markers individually. In this paper we propose a novel statistical approach for multi-marker analysis based on the Rasch model. The method summarizes the categorical genotypes of SNPs by a generalized logistic function into a genetic score that can be used for association analysis. Through different sets of simulations, the false-positive rate and power of the proposed approach are compared to a set of existing methods, and shows good performances. The application of the Rasch model on Alzheimer's Disease (AD ADNI GWAS dataset also allows a coherent interpretation of the results. Our analysis supports the idea that APOE is a major susceptibility gene for AD. In the top genes selected by proposed method, several could be functionally linked to AD. In particular, a pathway analysis of these genes also highlights the metabolism of cholesterol, that is known to play a key role in AD pathogenesis. Interestingly, many of these top genes can be integrated in a hypothetic signalling network.

Using Rasch Analysis to Evaluate the Reliability and Validity of the Swallowing Quality of Life Questionnaire: An Item Response Theory Approach.

Science.gov (United States)

Cordier, Reinie; Speyer, Renée; Schindler, Antonio; Michou, Emilia; Heijnen, Bas Joris; Baijens, Laura; Karaduman, Ayşe; Swan, Katina; Clavé, Pere; Joosten, Annette Veronica

2018-02-01

The Swallowing Quality of Life questionnaire (SWAL-QOL) is widely used clinically and in research to evaluate quality of life related to swallowing difficulties. It has been described as a valid and reliable tool, but was developed and tested using classic test theory. This study describes the reliability and validity of the SWAL-QOL using item response theory (IRT; Rasch analysis). SWAL-QOL data were gathered from 507 participants at risk of oropharyngeal dysphagia (OD) across four European countries. OD was confirmed in 75.7% of participants via videofluoroscopy and/or fiberoptic endoscopic evaluation, or a clinical diagnosis based on meeting selected criteria. Patients with esophageal dysphagia were excluded. Data were analysed using Rasch analysis. Item and person reliability was good for all the items combined. However, person reliability was poor for 8 subscales and item reliability was poor for one subscale. Eight subscales exhibited poor person separation and two exhibited poor item separation. Overall item and person fit statistics were acceptable. However, at an individual item fit level results indicated unpredictable item responses for 28 items, and item redundancy for 10 items. The item-person dimensionality map confirmed these findings. Results from the overall Rasch model fit and Principal Component Analysis were suggestive of a second dimension. For all the items combined, none of the item categories were 'category', 'threshold' or 'step' disordered; however, all subscales demonstrated category disordered functioning. Findings suggest an urgent need to further investigate the underlying structure of the SWAL-QOL and its psychometric characteristics using IRT.

Lipid ratio as a suitable tool to identify individuals with MetS risk: A case- control study.

Science.gov (United States)

Abbasian, Maryam; Delvarianzadeh, Mehri; Ebrahimi, Hossein; Khosravi, Farideh

2017-11-01

This study aimed to compare the serum lipids ratio in staff with and without metabolic syndrome (MetS) who were working in Shahroud University of Medical Sciences. This case-control study was conducted in 2015 on 499 personnel aged 30-60 years old. ATP III criteria were used to diagnose patients with MetS. The data were analyzed by using logistic regression and ROC curve. Mean lipid ratio was higher in individuals having the MetS in both sexes compared with those without. In addition, the mean levels of lipid ratios significantly increased with increasing number of MetS components in both sexes. Also it could be concluded that TG/HDL-C ratio is the best marker for the diagnosis of MetS in men and women. Moreover, the cut-off point for the TG/HDL-C was 2.86 in women and 4.03 in men. It was found that for any unit of increases in the TG/HDL-C, the risk of developing the MetS will increase by 2.12 times. TG/HDL-C ratio is found to be the best clinical marker for the diagnosis of MetS compare with other lipid ratios, therefore it is recommended to be used as a feasible tool to identify individuals with MetS risk. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Rasch-modeling the Portuguese SOCRATES in a clinical sample.

Science.gov (United States)

Lopes, Paulo; Prieto, Gerardo; Delgado, Ana R; Gamito, Pedro; Trigo, Hélder

2010-06-01

The Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES) assesses motivation for treatment in the drug-dependent population. The development of adequate measures of motivation is needed in order to properly understand the role of this construct in rehabilitation. This study probed the psychometric properties of the SOCRATES in the Portuguese population by means of the Rasch Rating Scale Model, which allows the conjoint measurement of items and persons. The participants were 166 substance abusers under treatment for their addiction. Results show that the functioning of the five response categories is not optimal; our re-analysis indicates that a three-category system is the most appropriate one. By using this response category system, both model fit and estimation accuracy are improved. The discussion takes into account other factors such as item format and content in order to make suggestions for the development of better motivation-for-treatment scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

A Comparison between Discrimination Indices and Item-Response Theory Using the Rasch Model in a Clinical Course Written Examination of a Medical School.

Science.gov (United States)

Park, Jong Cook; Kim, Kwang Sig

2012-03-01

The reliability of test is determined by each items' characteristics. Item analysis is achieved by classical test theory and item response theory. The purpose of the study was to compare the discrimination indices with item response theory using the Rasch model. Thirty-one 4th-year medical school students participated in the clinical course written examination, which included 22 A-type items and 3 R-type items. Point biserial correlation coefficient (C(pbs)) was compared to method of extreme group (D), biserial correlation coefficient (C(bs)), item-total correlation coefficient (C(it)), and corrected item-total correlation coeffcient (C(cit)). Rasch model was applied to estimate item difficulty and examinee's ability and to calculate item fit statistics using joint maximum likelihood. Explanatory power (r2) of Cpbs is decreased in the following order: C(cit) (1.00), C(it) (0.99), C(bs) (0.94), and D (0.45). The ranges of difficulty logit and standard error and ability logit and standard error were -0.82 to 0.80 and 0.37 to 0.76, -3.69 to 3.19 and 0.45 to 1.03, respectively. Item 9 and 23 have outfit > or =1.3. Student 1, 5, 7, 18, 26, 30, and 32 have fit > or =1.3. C(pbs), C(cit), and C(it) are good discrimination parameters. Rasch model can estimate item difficulty parameter and examinee's ability parameter with standard error. The fit statistics can identify bad items and unpredictable examinee's responses.

Quality of life in the Danish general population--normative data and validity of WHOQOL-BREF using Rasch and item response theory models

DEFF Research Database (Denmark)

Noerholm, V; Groenvold, M; Watt, T

2004-01-01

BACKGROUND: The main objective of this study was to investigate the construct validity of the WHOQOL-BREF by use of Rasch and Item Response Theory models and to examine the stability of the model across high/low scoring individuals, gender, education, and depressive illness. Furthermore......, the objective of the study was to estimate the reference data for the quality of life questionnaire WHOQOL-BREF in the general Danish population and in subgroups defined by age, gender, and education. METHODS: Mail-out-mail-back questionnaires were sent to a randomly selected sample of the Danish general...... population. The response rate was 68.5%, and the sample reported here contained 1101 respondents: 578 women and 519 men (four respondents did not indicate their genders). RESULTS: Each of the four domains of the WHOQOL-BREF scale fitted a two-parameter IRT model, but did not fit the Rasch model. Due...

Brazilian WHOQOL-OLD Module version: a Rasch analysis of a new instrument Versão em português do Módulo WHOQOL-OLD: análise de Rasch de um novo instrumento

Directory of Open Access Journals (Sweden)

Eduardo Chachamovich

2008-04-01

Full Text Available OBJECTIVE: To evaluate the Brazilian version of WHOQOL-OLD Module and to test potential changes to the instrument to increase its psychometric adequacy. METHODS: A total of 424 older adults living in a city in Southern Brazil completed the WHOQOL-OLD instrument, in 2005. Rasch analysis was used to explore the psychometric performance of the scale, as implemented by the RUMM2020 software. Item-trait interaction, threshold disorders, presence of differential item functioning and item fit, were analyzed. RESULTS: Two ("death and dying" and "sensory abilities" out of six domains showed inadequate item-trait interactions. Rescoring the response scale and deleting the most misperforming items led to scale improvement. The evaluation of domains and items individually showed that the "intimacy" domain does perform well in contrast to the findings using the classical approach. In addition, the "sensory abilities" domain does not derive an interval measure in its current format. CONCLUSIONS: Unidimensionality and local independence were seen in all domains. Changes in the response scale and deletion of problematic items improved the scale's performance.OBJETIVO: Analisar a versão brasileira do Módulo WHOQOL-OLD, indicando alterações potenciais do instrumento para aumentar a adequação psicométrica. MÉTODOS: O total de 424 idosos residentes em Porto Alegre, RS, responderam o instrumento WHOQOL-OLD em 2005. O modelo de Rasch foi utilizado para a análise do desempenho psicométrico da escala, a partir do software RUMM2020. Foram analisadas a interação item-traço, a presença de funcionamento diferencial dos itens e a adequação dos itens ao modelo de Rasch. RESULTADOS: Dois domínios ("morte e morrer" e "funcionamento do sensório" apresentaram interação item-total insuficiente. Remodelar a escala de resposta e excluir itens com pior performance resultou em melhora da escala. A análise dos domínios e itens individualmente foi capaz de indicar

C-MET overexpression and amplification in gliomas.

Science.gov (United States)

Kwak, Yoonjin; Kim, Seong-Ik; Park, Chul-Kee; Paek, Sun Ha; Lee, Soon-Tae; Park, Sung-Hye

2015-01-01

We investigated c-Met overexpression and MET gene amplification in gliomas to determine their incidence and prognostic significance. c-Met immunohistochemistry and MET gene fluorescence in situ hybridization were carried out on tissue microarrays from 250 patients with gliomas (137 grade IV GBMs and 113 grade II and III diffuse gliomas). Clinicopathological features of these cases were reviewed. c-Met overexpression and MET gene amplification were detected in 13.1% and 5.1% of the GBMs, respectively. All the MET-amplified cases showed c-Met overexpression, but MET amplification was not always concordant with c-Met overexpression. None of grade II and III gliomas demonstrated c-Met overexpression or MET gene amplification. Mean survival of the GBM patients with MET amplification was not significantly different from patients without MET amplification (P=0.155). However, GBM patients with c-Met overexpression survived longer than patients without c-Met overexpression (P=0.035). Although MET amplification was not related to poor GBM prognosis, it is partially associated with the aggressiveness of gliomas, as MET amplification was found only in grade IV, not in grade II and III gliomas. We suggest that MET inhibitor therapy may be beneficial in about 5% GBMs, which was the incidence of MET gene amplification found in the patients included in this study.

Samen in Zee met Zelfregulatie: Een Design-Based Aanpak met Vmbo Leraren

NARCIS (Netherlands)

Jossberger, Helen; Brand-Gruwel, Saskia; Boshuizen, Els; Van de Wiel, Margje

2010-01-01

Jossberger, H., Brand-Gruwel, S., Boshuizen, H. P. A., & Van der Wiel, M. (2010, June). Samen in Zee met Zelfregulatie: Een Design-Based Aanpak met Vmbo Leraren. Poster presented at the 37th Onderwijs Research Dagen (ORD), Enschede, Nederland.

Using the Many-Faceted Rasch Model to Evaluate Standard Setting Judgments: An Illustration with the Advanced Placement Environmental Science Exam

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Kaliski, Pamela K.; Wind, Stefanie A.; Engelhard, George, Jr.; Morgan, Deanna L.; Plake, Barbara S.; Reshetar, Rosemary A.

2013-01-01

The many-faceted Rasch (MFR) model has been used to evaluate the quality of ratings on constructed response assessments; however, it can also be used to evaluate the quality of judgments from panel-based standard setting procedures. The current study illustrates the use of the MFR model for examining the quality of ratings obtained from a standard…

Measurement of Online Student Engagement: Utilization of Continuous Online Student Behavior Indicators as Items in a Partial Credit Rasch Model

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Anderson, Elizabeth

2017-01-01

Student engagement has been shown to be essential to the development of research-based best practices for K-12 education. It has been defined and measured in numerous ways. The purpose of this research study was to develop a measure of online student engagement for grades 3 through 8 using a partial credit Rasch model and validate the measure…

Bilimsel Araştırma Ödevlerinin Çok Yüzeyli Rasch Ölçme Modeli ile Değerlendirilmesi

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Ramazan BAŞTÜRK

2010-06-01

Full Text Available The purpose of this study is to investigate the usefulness of the many-facet Rasch model (MFRM in evaluating the quality of performance related to preparing Research assignment in higher education. The Rasch Model utilizes item response theory stating that the probability of a correct response to a test item/task depends largely on a single parameter, the ability of the person. MFRM extends this one-parameter model to other facets, for example, rater severity, rating scale format, task difficulty levels. This paper specifically investigated research preparation ability in terms of items/task difficulty and rater severity/leniency. Fourth year counseling students prepared research assignments during the autumn semester of the 2009-2010 school years in the “Research Methods in Education” course. Six judges evaluated each students assignments using “Research Assignment Evaluation Rubric”. The results of this study demonstrated that the MFRM is a powerful tool for handling polytomous data in performance and peer assessment in higher education.

Gendered language attitudes: exploring language as a gendered construct using Rasch measurement theory.

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Knisely, Kris A; Wind, Stefanie A

2015-01-01

Gendered language attitudes (GLAs) are gender-based perceptions of language varieties based on connections between gender-related and linguistic characteristics of individuals, including the perception of language varieties as possessing degrees of masculinity and femininity. This study combines substantive theory about language learning and gender with a model based on Rasch measurement theory to explore the psychometric properties of a new measure of GLAs. Findings suggest that GLAs is a unidimensional construct and that the items used can be used to describe differences among students in terms of the strength of their GLAs. Implications for research, theory, and practice are discussed. Special emphasis is given to the teaching and learning of languages.

Profil Perencanaan Karir Siswa Sekolah Menengah Kejuruan dengan Pemodelan Rasch Berdasarkan Jenis Kelamin

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Itsar Bolo Rangka

2017-08-01

Full Text Available This research aimed to (1 perform inventory career planning of students, and (2 measuring students career planning based on gender. Data analysis used Rasch model for 45 students with actual power measurement 0.9272652. The research findings showed (1 inventory career planning has been fit with the theoretic model, and (2 female student have a tendency to a higher career planning rather than male student. In the future, to measurement of student’s career planning by using this inventory can only produce a high measurement information for students who have a mediocre ability. Further, the researcher need to consider to eliminate item No. 12 in this inventory due to the biased towards the male gender.

Acceptance on Mobile Learning via SMS: A Rasch Model Analysis

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Issham Ismail

2010-04-01

Full Text Available This study investigated whether mobile learning via Short Message Service (SMS-learning is accepted by the students enrolled in the distance learning academic programme in the Universiti Sains Malaysia. This study explored the impact of perceived usefulness, perceived ease of use and usability of the system to their acceptability. The survey was constructed using a questionnaire consisting of statements regarding the participants’ demographics, experiences in and perception of using mobile learning via SMS, involving 105 students from management and sciences disciplines. The Rasch Model Analysis was used for measurement correspond to a 5 point Likert. Results indicated that the usability of the system contributed to be effectiveness in assisting the students with their study. Respondents agree that SMS-learning is easy, effective and useful to help them study. However, the results found that there has been a problem in mobile learning that less interaction with lecturers. It implies that the acceptability of students to this mode on communication and interaction is highly endorsed.

A psychometric evaluation of the Swedish version of the Research Utilization Questionnaire using a Rasch measurement model.

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Lundberg, Veronica; Boström, Anne-Marie; Malinowsky, Camilla

2017-07-30

Evidence-based practice and research utilisation has become a commonly used concept in health care. The Research Utilization Questionnaire (RUQ) has been recognised to be a widely used instrument measuring the perception of research utilisation among nursing staff in clinical practice. Few studies have however analysed the psychometric properties of the RUQ. The aim of this study was to examine the psychometric properties of the Swedish version of the three subscales in RUQ using a Rasch measurement model. This study has a cross-sectional design using a sample of 163 staff (response rate 81%) working in one nursing home in Sweden. Data were collected using the Swedish version of RUQ in 2012. The three subscales Attitudes towards research, Availability of and support for research use and Use of research findings in clinical practice were investigated. Data were analysed using a Rasch measurement model. The results indicate presence of multidimensionality in all subscales. Moreover, internal scale validity and person response validity also provide some less satisfactory results, especially for the subscale Use of research findings. Overall, there seems to be a problem with the negatively worded statements. The findings suggest that clarification and refining of items, including additional psychometric evaluation of the RUQ, are needed before using the instrument in clinical practice and research studies among staff in nursing homes. © 2017 Nordic College of Caring Science.

Augmenting the Genetic Toolbox for Sulfolobus islandicus with a Stringent Positive Selectable Marker for Agmatine Prototrophy

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Cooper, Tara E.; Krause, David J.

2013-01-01

Sulfolobus species have become the model organisms for studying the unique biology of the crenarchaeal division of the archaeal domain. In particular, Sulfolobus islandicus provides a powerful opportunity to explore natural variation via experimental functional genomics. To support these efforts, we further expanded genetic tools for S. islandicus by developing a stringent positive selection for agmatine prototrophs in strains in which the argD gene, encoding arginine decarboxylase, has been deleted. Strains with deletions in argD were shown to be auxotrophic for agmatine even in nutrient-rich medium, but growth could be restored by either supplementation of exogenous agmatine or reintroduction of a functional copy of the argD gene from S. solfataricus P2 into the ΔargD host. Using this stringent selection, a robust targeted gene knockout system was established via an improved next generation of the MID (marker insertion and unmarked target gene deletion) method. Application of this novel system was validated by targeted knockout of the upsEF genes involved in UV-inducible cell aggregation formation. PMID:23835176

Sereniteit met een dip

NARCIS (Netherlands)

dr Ed de Jonge

2015-01-01

Boekbespreking van Serendipiteit. De ongezochte vondst. Het boek opent met een verzameling van citaten die direct of indirect met het onderwerp samenhangen. Daarna volgt een kort voorwoord van Hans Clevers, de toenmalige president van de KNAW, die een lans breekt voor serendipiteit in de biologie.

Using Rasch models to develop and validate an environmental thinking learning progression

Science.gov (United States)

Hashimoto-Martell, Erin A.

Environmental understanding is highly relevant in today's global society. Social, economic, and political structures are connected to the state of environmental degradation and exploitation, and disproportionately affect those in poor or urban communities (Brulle & Pellow, 2006; Executive Order No. 12898, 1994). Environmental education must challenge the way we live, and our social and ecological quality of life, with the goal of responsible action. The development of a learning progression in environmental thinking, along with a corresponding assessment, could provide a tool that could be used across environmental education programs to help evaluate and guide programmatic decisions. This study sought to determine if a scale could be constructed that allowed individuals to be ordered along a continuum of environmental thinking. First, I developed the Environmental Thinking Learning Progression, a scale of environmental thinking from novice to advanced, based on the current available research and literature. The scale consisted of four subscales, each measuring a different aspect of environmental thinking: place consciousness, human connection, agency, and science concepts. Second, a measurement instrument was developed, so that the data appropriately fit the model using Rasch analysis. A Rasch analysis of the data placed respondents along a continuum, given the range of item difficulty for each subscale. Across three iterations of instrument revision and data collection, findings indicated that the items were ordered in a hierarchical way that corresponded to the construct of environmental thinking. Comparisons between groups showed that the average score of respondents who had participated in environmental education programs was significantly higher than those who had not. A comparison between males and females showed no significant difference in average measure, however, there were varied significant differences between how racial/ethnic groups performed. Overall

Psychometrics evaluation of Charcot-Marie-Tooth Neuropathy Score (CMTNSv2) second version, using Rasch analysis.

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Sadjadi, Reza; Reilly, Mary M; Shy, Michael E; Pareyson, Davide; Laura, Matilde; Murphy, Sinead; Feely, Shawna M E; Grider, Tiffany; Bacon, Chelsea; Piscosquito, Giuseppe; Calabrese, Daniela; Burns, Ted M

2014-09-01

Charcot-Marie-Tooth Neuropathy Score second version (CMTNSv2) is a validated clinical outcome measure developed for use in clinical trials to monitor disease impairment and progression in affected CMT patients. Currently, all items of CMTNSv2 have identical contribution to the total score. We used Rasch analysis to further explore psychometric properties of CMTNSv2, and in particular, category response functioning, and their weight on the overall disease progression. Weighted category responses represent a more accurate estimate of actual values measuring disease severity and therefore could potentially be used in improving the current version. © 2014 Peripheral Nerve Society.

Precisão de avaliadores na avaliação da criatividade por meio da produção de metáforas Inter rater reliability in the creativity assessment using metaphor production

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Ricardo Primi

2007-12-01

Full Text Available A criatividade é um dos temas da psicologia cuja mensuração está circundada de dificuldades, já que é uma área carente de bons instrumentos. Metáforas como "O camelo é o barco do deserto" são meios de expressão de aspectos diferente de algum conceito (camelo por meio da associação de idéias. A elaboração de metáforas desse tipo pressupõe a execução de processos cognitivos básicos, tais como o raciocínio analógico e as associações remotas, processos esses que estão associados aos componentes cognitivos da criatividade. Objetivou-se nesta pesquisa estudar a precisão de critérios de pontuação de um instrumento de avaliação da criatividade por meio de produção de metáforas que avalia respostas metafóricas a partir de um estímulo do tipo "O camelo é o ______ do deserto". Participaram deste estudo 19 sujeitos e nove juízes. O teste de metáforas é composto por nove itens, aos quais os sujeitos deram um total de 513 respostas. Cada resposta foi avaliada independentemente pelos juízes, em uma escala de 0 a 3, indicando o nível de elaboração da metáfora. A precisão foi calculada a partir do modelo de Rasch, assumindo cada idéia como um caso e cada juiz como um item de um teste hipotético, aplicando-se um procedimento chamado rede de juízes ancorados. A precisão de avaliadores variou de 0,52 a 0,83, com média 0,74 (DP=0,08, indicando uma boa precisão de avaliadores.The measure of creativity is a difficult task in psychology and consequently there is a shortage of good quality instruments. Metaphors, like "The camel is the boat of the desert", are means of expressing different characteristics of a concept (camel through association of ideas. The creation of such metaphors assumes the accomplishment of basic cognitive processes, like analogical reasoning and remote associations, which are linked to the creativity cognitive processess. The goal of this research was to study the reliability of scoring system

Rasch Measurement in Language Research: Creating the Foreign Language Classroom Anxiety Inventory

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Miranda J. Walker

2014-11-01

Full Text Available The purpose of this study was to construct a new scale for measuring foreign language classroom anxiety (FLCA. It begun with the creation of an extended item pool generated by qualitative methods. Subsequent Rasch and semantic analyses led to the final 18-item Foreign Language Classroom Anxiety Inventory (FLCAI. In comparison with the Foreign Language Classroom Anxiety Scale (FLCAS, the FLCAI demonstrated more convincing evidence of unidimensionality and the optimal 5-point Likert scale functioned better. The FLCAI, while 55% the length of the FLCAS, thus more practical for classroom practitioners to administer and analyse, maintains its psychometric properties and covers a wider range on the construct continuum thus improving the degree of validity of the instrument. Finally, test anxiety was shown to be a component of FLCA.

Air Quality and Health Benefits of China's Recent Stringent Environmental Policy

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Zheng, Y.; Xue, T.; Zhang, Q.; Geng, G.; He, K.

2016-12-01

Aggressive emission control measures were taken by China's central and local governments after the promulgation of the "Air Pollution Prevention and Control Action Plan" in 2013. We evaluated the air quality and health benefits of this ever most stringent air pollution control policy during 2013-2015 by utilizing a two-stage data fusion model and newly-developed cause-specific integrated exposure-response functions (IER) developed for the Global Burden of Disease (GBD). The two-stage data fusion model predicts spatiotemporal continuous PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) concentrations by integrating satellite-derived aerosol optical depth (AOD) measurements, PM2.5 concentrations from measurement and air quality model, and other ancillary information. During the years of analysis, PM2.5 concentration dropped significantly on national average and over heavily polluted regions as identified by Mann-Kendall analysis. The national PM2.5-attributable mortality decreased by 72.8 (95% CI: 59.4, 85.2) thousand (6%) from 1.23 (95% CI: 1.06, 1.39) million in 2013 to 1.15 (95% CI: 0.98, 1.31) million in 2015 due to considerable reduction (i.e. 18%) of population-weighted PM2.5 from 61.4 to 50.5 µg/m3. Meteorological variations between 2013 and 2015 were estimated to raise the PM2.5 levels by 0.24 µg/m3 and national mortality by 2.1 (95% CI: 1.6, 2.6) thousand through sensitivity tests, which implies the dominant role of anthropogenic impacts on PM2.5 abatement and attributable mortality reduction. Our study affirms the effectiveness of China's recent air quality policy, however, due to the possible supralinear shape of C-R functions, health benefits induced by air quality improvement in these years are limited. We therefore appeal for continuous implementation of current policies and further stringent measures from both air quality improvement and public health protection perspectives.

Patient self-report section of the ASES questionnaire: a Spanish validation study using classical test theory and the Rasch model.

Science.gov (United States)

Vrotsou, Kalliopi; Cuéllar, Ricardo; Silió, Félix; Rodriguez, Miguel Ángel; Garay, Daniel; Busto, Gorka; Trancho, Ziortza; Escobar, Antonio

2016-10-18

The aim of the current study was to validate the self-report section of the American Shoulder and Elbow Surgeons questionnaire (ASES-p) into Spanish. Shoulder pathology patients were recruited and followed up to 6 months post treatment. The ASES-p, Constant, SF-36 and Barthel scales were filled-in pre and post treatment. Reliability was tested with Cronbach's alpha, convergent validity with Spearman's correlations coefficients. Confirmatory factor analysis (CFA) and the Rasch model were implemented for assessing structural validity and unidimensionality of the scale. Models with and without the pain item were considered. Responsiveness to change was explored via standardised effect sizes. Results were acceptable for both tested models. Cronbach's alpha was 0.91, total scale correlations with Constant and physical SF-36 dimensions were >0.50. Factor loadings for CFA were >0.40. The Rasch model confirmed unidimensionality of the scale, even though item 10 "do usual sport" was suggested as non-informative. Finally, patients with improved post treatment shoulder function and those receiving surgery had higher standardised effect sizes. The adapted Spanish ASES-p version is a valid and reliable tool for shoulder evaluation and its unidimensionality is supported by the data.

Developing the Polish Educational Needs Assessment Tool (Pol-ENAT) in rheumatoid arthritis and systemic sclerosis: a cross-cultural validation study using Rasch analysis.

Science.gov (United States)

Sierakowska, Matylda; Sierakowski, Stanisław; Sierakowska, Justyna; Horton, Mike; Ndosi, Mwidimi

2015-03-01

To undertake cross-cultural adaptation and validation of the educational needs assessment tool (ENAT) for use with people with rheumatoid arthritis (RA) and systemic sclerosis (SSc) in Poland. The study involved two main phases: (1) cross-cultural adaptation of the ENAT from English into Polish and (2) Cross-cultural validation of Polish Educational Needs Assessment Tool (Pol-ENAT). The first phase followed an established process of cross-cultural adaptation of self-report measures. The second phase involved completion of the Pol-ENAT by patients and subjecting the data to Rasch analysis to assess the construct validity, unidimensionality, internal consistency and cross-cultural invariance. An adequate conceptual equivalence was achieved following the adaptation process. The dataset for validation comprised a total of 278 patients, 237 (85.3 %) of which were female. In each disease group (145, RA and 133, SSc), the 7 domains of the Pol-ENAT were found to fit the Rasch model, X (2)(df) = 16.953(14), p = 0.259 and 8.132(14), p = 0.882 for RA and SSc, respectively. Internal consistency of the Pol-ENAT was high (patient separation index = 0.85 and 0.89 for SSc and RA, respectively), and unidimensionality was confirmed. Cross-cultural differential item functioning (DIF) was detected in some subscales, and DIF-adjusted conversion tables were calibrated to enable cross-cultural comparison of data between Poland and the UK. Using a standard process in cross-cultural adaptation, conceptual equivalence was achieved between the original (UK) ENAT and the adapted Pol-ENAT. Fit to the Rasch model, confirmed that the construct validity, unidimensionality and internal consistency of the ENAT have been preserved.

Metsämaisema ulkoilijoiden kokemana

OpenAIRE

Vuohijoki, Jaana

2010-01-01

Työn aiheena oli tutkia, miten ulkoilijat kokevat metsämaiseman Tampereella. Tavoitteena oli selvittää ulkoilijoiden maisema-arvostuksia sekä suhtautumista metsänhoidon toimenpiteisiin. Tutkimus toteutettiin maastohaastatteluina Tampereella kolmella eri asuinalueella: Hallilassa, Leinolassa ja Tesomajärvellä. Otoskooksi muodostui kymmenen haastattelua aluetta kohti, mutta yhdeltä vastaajalta ei ehditty kysyä kaikkia kysymyksiä. Vastaajat olivat yleisesti ottaen tyytyväisiä alueiden metsän...

Mars MetNet Mission Status

Science.gov (United States)

Harri, A.-M.; Aleksashkin, S.; Arruego, I.; Schmidt, W.; Genzer, M.; Vazquez, L.; Haukka, H.; Palin, M.; Nikkanen, T.

2015-10-01

New kind of planetary exploration mission for Mars is under development in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semihard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested.

Word je met Donkey Konga een betere muzikant? : Muziek leren spelen met de spelcomputer

NARCIS (Netherlands)

Tom Langhorst

2010-01-01

Kan de spelcomputer behulpzaam zijn bij de ontwikkeling van het muzikale gevoel? Met die vraag in het achterhoofd bekijkt Tom Langhorst hier kritisch het Nintendo-spel Donkey Konga, waarin de speler mee kan drummen met bekende popsongs.

Mars MetNet Mission Status

Science.gov (United States)

Harri, Ari-Matti; Aleksashkin, Sergei; Arruego, Ignacio; Schmidt, Walter; Genzer, Maria; Vazquez, Luis; Haukka, Harri

2015-04-01

New kind of planetary exploration mission for Mars is under development in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semi-hard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested. 1. MetNet Lander The MetNet landing vehicles are using an inflatable entry and descent system instead of rigid heat shields and parachutes as earlier semi-hard landing devices have used. This way the ratio of the payload mass to the overall mass is optimized. The landing impact will burrow the payload container into the Martian soil providing a more favorable thermal environment for the electronics and a suitable orientation of the telescopic boom with external sensors and the radio link antenna. It is planned to deploy several tens of MNLs on the Martian surface operating at least partly at the same time to allow meteorological network science. 2. Scientific Payload The payload of the two MNL precursor models includes the following instruments: Atmospheric instruments: 1. MetBaro Pressure device 2. MetHumi Humidity device 3. MetTemp Temperature sensors Optical devices: 1. PanCam Panoramic 2. MetSIS Solar irradiance sensor with OWLS optical wireless system for data transfer 3. DS Dust sensor The descent processes dynamic properties are monitored by a special 3-axis accelerometer combined with a 3-axis gyrometer. The data will be sent via auxiliary beacon antenna throughout the

A Rasch analysis of patients' opinions of primary health care professionals' ethical behaviour with respect to communication issues.

Science.gov (United States)

González-de Paz, Luis; Kostov, Belchin; López-Pina, Jose A; Solans-Julián, Pilar; Navarro-Rubio, M Dolors; Sisó-Almirall, Antoni

2015-04-01

Patients' opinions are crucial in assessing the effectiveness of the ethical theories which underlie the care relationship between patients and primary health care professionals. To study the ethical behaviour of primary health care professionals with respect to communication issues according to patients' opinions. Cross-sectional study using a self-administered questionnaire in patients from a network of 15 urban primary health centres. Participants were patients attended at the centres when the study was conducted. We used a Rasch analysis to verify the structure of the 17 questionnaire items, and to calculate interval level measures for patients and items. We analysed differences according to patient subgroups using analysis of variance tests and differences between the endorsement of each item. We analysed 1013 (70.34%) of questionnaires. Data fit to the Rasch model was achieved after collapsing two categories and eliminating five items. Items with the lowest degree of endorsement were related to the management of differences in conflictive situations between patients and health care professionals. We found significant differences (P communication skills were respected by family physicians and nurses. However, opinions on endorsement were lower when patients disagreed with health care professionals. The differences found between patient subgroups demonstrated the importance of trust and confidence between patients and professionals. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Exploring students’ perceived and actual ability in solving statistical problems based on Rasch measurement tools

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Azila Che Musa, Nor; Mahmud, Zamalia; Baharun, Norhayati

2017-09-01

One of the important skills that is required from any student who are learning statistics is knowing how to solve statistical problems correctly using appropriate statistical methods. This will enable them to arrive at a conclusion and make a significant contribution and decision for the society. In this study, a group of 22 students majoring in statistics at UiTM Shah Alam were given problems relating to topics on testing of hypothesis which require them to solve the problems using confidence interval, traditional and p-value approach. Hypothesis testing is one of the techniques used in solving real problems and it is listed as one of the difficult concepts for students to grasp. The objectives of this study is to explore students’ perceived and actual ability in solving statistical problems and to determine which item in statistical problem solving that students find difficult to grasp. Students’ perceived and actual ability were measured based on the instruments developed from the respective topics. Rasch measurement tools such as Wright map and item measures for fit statistics were used to accomplish the objectives. Data were collected and analysed using Winsteps 3.90 software which is developed based on the Rasch measurement model. The results showed that students’ perceived themselves as moderately competent in solving the statistical problems using confidence interval and p-value approach even though their actual performance showed otherwise. Item measures for fit statistics also showed that the maximum estimated measures were found on two problems. These measures indicate that none of the students have attempted these problems correctly due to reasons which include their lack of understanding in confidence interval and probability values.

Induction of a stringent metabolic response in intracellular stages of Leishmania mexicana leads to increased dependence on mitochondrial metabolism.

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Eleanor C Saunders

2014-01-01

Full Text Available Leishmania parasites alternate between extracellular promastigote stages in the insect vector and an obligate intracellular amastigote stage that proliferates within the phagolysosomal compartment of macrophages in the mammalian host. Most enzymes involved in Leishmania central carbon metabolism are constitutively expressed and stage-specific changes in energy metabolism remain poorly defined. Using (13C-stable isotope resolved metabolomics and (2H2O labelling, we show that amastigote differentiation is associated with reduction in growth rate and induction of a distinct stringent metabolic state. This state is characterized by a global decrease in the uptake and utilization of glucose and amino acids, a reduced secretion of organic acids and increased fatty acid β-oxidation. Isotopomer analysis showed that catabolism of hexose and fatty acids provide C4 dicarboxylic acids (succinate/malate and acetyl-CoA for the synthesis of glutamate via a compartmentalized mitochondrial tricarboxylic acid (TCA cycle. In vitro cultivated and intracellular amastigotes are acutely sensitive to inhibitors of mitochondrial aconitase and glutamine synthetase, indicating that these anabolic pathways are essential for intracellular growth and virulence. Lesion-derived amastigotes exhibit a similar metabolism to in vitro differentiated amastigotes, indicating that this stringent response is coupled to differentiation signals rather than exogenous nutrient levels. Induction of a stringent metabolic response may facilitate amastigote survival in a nutrient-poor intracellular niche and underlie the increased dependence of this stage on hexose and mitochondrial metabolism.

Construct validity of the psychological general well being index (PGWBI in a sample of patients undergoing treatment for stress-related exhaustion: a rasch analysis

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Lundgren-Nilsson Åsa

2013-01-01

Full Text Available Abstract Purpose The Psychological General Well Being Index (PGWBI is a widely used scale across many conditions. Over time issues have been raised about the dimensional structure of the scale, and it has not yet been subjected to scrutiny by modern Psychometric approaches. The current study thus evaluates the PGWBI with Rasch- and factor analysis. Methods Consecutive patients recruited to a tertiary stress clinic were administered the PGBWI as part of routine clinical assessment at baseline and three months. Data from the scale was subjected to Factor Analyses and to Rasch analysis. In both cases adjustments for local independence violations were allowed. Results 179 patients were recruited, with a mean age of 43 years, and of whom 70% were female. An initial Confirmatory Factor Analysis (CFA with baseline data failed, but the modification indices also indicated considerable levels of local dependency requiring errors to be correlated. An EFA highlighted positive and negative effect domains. Rasch analysis confirmed that fit of data to the model was influenced by local dependency, and that in practice if the items from the six underlying domains were treated as six ‘super’ items, the scale was shown to measure one dominant construct of well being. An interval scale transformation was therefore possible. A significant improvement in well-being was observed over a three month period. Conclusion The PGWBI scale has satisfactory internal construct validity when tested with modern psychometric techniques, using data obtained from patients treated for stress-related exhaustion. The instrument has qualities that make it suitable also for monitoring well-being during interventions for stress-related exhaustion/clinical burnout.

Validación de la escala para manía de la Universidad Nacional de Colombia usando el análisis de Rasch

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Ricardo Sánchez

2011-03-01

Conclusiones. En este primer estudio de la escala para manías usando el análisis de Rasch, se detectó mal ajuste y redundancia de algunos ítems. El síndrome maníaco no queda completamente evaluado por la escala. El instrumento podría mejorarse agregando síntomas depresivos.

Physics Metacognition Inventory Part II: Confirmatory factor analysis and Rasch analysis

Science.gov (United States)

Taasoobshirazi, Gita; Bailey, MarLynn; Farley, John

2015-11-01

The Physics Metacognition Inventory was developed to measure physics students' metacognition for problem solving. In one of our earlier studies, an exploratory factor analysis provided evidence of preliminary construct validity, revealing six components of students' metacognition when solving physics problems including knowledge of cognition, planning, monitoring, evaluation, debugging, and information management. The college students' scores on the inventory were found to be reliable and related to students' physics motivation and physics grade. However, the results of the exploratory factor analysis indicated that the questionnaire could be revised to improve its construct validity. The goal of this study was to revise the questionnaire and establish its construct validity through a confirmatory factor analysis. In addition, a Rasch analysis was applied to the data to better understand the psychometric properties of the inventory and to further evaluate the construct validity. Results indicated that the final, revised inventory is a valid, reliable, and efficient tool for assessing student metacognition for physics problem solving.

Using Rasch Measurement To Investigate the Cross-form Equivalence and Clinical Utility of Spanish and English Versions of a Diabetes Questionnaire: A Pilot Study.

Science.gov (United States)

Gerber, Ben; Smith, Everett V., Jr.; Girotti, Mariela; Pelaez, Lourdes; Lawless, Kimberly; Smolin, Louanne; Brodsky, Irwin; Eiser, Arnold

2002-01-01

Used Rasch measurement to study the psychometric properties of data obtained from a newly developed Diabetes Questionnaire designed to measure diabetes knowledge, attitudes, and self-care. Responses of 26 diabetes patients to the English version of the questionnaire and 24 patients to the Spanish version support the cross-form equivalence and…

Measuring Health-Related Quality of Life in Strabismus: A Modification of the Adult Strabismus-20 (AS-20 Questionnaire Using Rasch Analysis.

Directory of Open Access Journals (Sweden)

Vijaya K Gothwal

Full Text Available To evaluate the psychometric properties of the Adult Strabismus-20 (AS-20- a health-related quality of life (HRQoL questionnaire in adults with strabismus, and if flawed, to revise the AS-20 and its subscales creating valid measurement scales.584 adults (meanage, 27.5 years with strabismus were recruited from an outpatient clinic at a South Indian tertiary eye care centre and were administered the AS-20 questionnaire.The AS-20 was translated and back translated into two Indian languages. The AS-20 and its two 10-item subscales - 'psychosocial' and 'function'were assessed separately for fit to the Rasch model, including an assessment of the rating scale, unidimensionality (by principal components analysis, measurement precision by person separation reliability, PSR, targeting, and differential item functioning (DIF; notable > 1.0 logits.Response categories were not used as intended, thereby, required re-organization and reducing their number from 5 to 3. The AS-20 had adequate measurement precision (PSR = 0.87 but lacked unidimensionality; however, deletion of the six multi-dimensionality causing items and an additional three misfitting items resulted in 11-item unidimensional questionnaire (AS-11. Two items failed to satisfy the model expectations in the 'psychosocial' subscale and were deleted - resulting in an 8-item unidimensional scale with adequate PSR (0.81 and targeting (0.23 logits. One item misfit in the 'function' subscale and was deleted-resulting in a 9 item Rasch-revised unidimensional subscale with acceptable PSR (0.80 and targeting (0.97 logits.None of the items displayed notable DIF by age, gender and level of education.The AS-11 and its two Rasch-revised subscales - 8-item psychosocial and 9-item function subscale may be more appropriate than the original AS-20 and its two 10-item subscales for use as unidimensional measures of HRQoL in adults with strabismus in India. Further work is required to establish the validity of the

Phase I Trial of Anti-MET Monoclonal Antibody in MET-Overexpressed Refractory Cancer.

Science.gov (United States)

Lee, Jeeyun; Kim, Seung Tae; Park, Sungju; Lee, Sujin; Park, Se Hoon; Park, Joon Oh; Lim, Ho Yeong; Ahn, Hongmo; Bok, Haesook; Kim, Kyoung-Mee; Ahn, Myung Ju; Kang, Won Ki; Park, Young Suk

2018-06-01

Samsung Advance Institute of Technology-301 (SAIT301) is a human immunoglobulin G2 antibody that can specifically target mesenchymal epithelial transition factor (c-MET). This novel antibody has higher priority over hepatocyte growth factors when binding to the Sema domain of c-MET and accelerates the internalization and degradation of c-MET, proving its powerful antitumor activities in intra- as well as extracellular areas. SAIT301 was administered intravenously once every 3 weeks in c-MET overexpressed solid tumor patients, focusing on metastatic colorectal cancer (CRC) according to common clinical phase I criteria. Dose escalation was performed according to a modified Fibonacci design, following the conventional 3+3 design. The purpose of this phase I study was to assess the safety profile, to establish the recommended dose for clinical phase II studies and to assess potential anticancer activity of the compound. Sixteen patients with a median age of 56 (range, 39-69) years were enrolled in the study. The most common adverse events were decreased appetite (50.0%), hypophosphatemia, fatigue and dizziness (25.0%, respectively), and diarrhea, blood alkaline phosphatase increased and dyspnea (18.8%, respectively). For tumor response, no patients achieved complete response. One (9.1%) CRC patient had a partial response in the 1.23 mg/kg group, 4 (36.4%) patients achieved stable disease (2 in the 0.41 mg/kg group, 2 in the 1.23 mg/kg group, 0 in the 3.69 mg/kg group, and 1 in the 8.61 mg/kg group). Because of the increase in dose-limiting toxicities (DLTs) at 8.61 mg/kg, the 3.69 mg/kg dose was considered the maximum tolerated dose and selected for further assessment in phase II. We successfully completed a phase I trial with MET antibody in a MET-overexpressed patient population focusing on CRC, and found that the DLTs were alkaline phosphatase elevation or hypophosphatemia. The recommended dose of SAIT301 for phase II is the dose of 3.69 mg/kg. Copyright © 2018

Microbewerking met behulp van lasers

NARCIS (Netherlands)

Ezendam, M.M.M.

1994-01-01

Het bewerken van materialen met behulp van lasers staat momenteel enorm in de belangstelling, en terecht. De ontwikkeling van bestaande en nieuwe typen lasers staat alles behalve stil. Ontwikkelingen bevinden zich met name in het gebied van hogere vermogens, betere bundelkwaliteit en hogere

Imputation by the mean score should be avoided when validating a Patient Reported Outcomes questionnaire by a Rasch model in presence of informative missing data

LENUS (Irish Health Repository)

Hardouin, Jean-Benoit

2011-07-14

Abstract Background Nowadays, more and more clinical scales consisting in responses given by the patients to some items (Patient Reported Outcomes - PRO), are validated with models based on Item Response Theory, and more specifically, with a Rasch model. In the validation sample, presence of missing data is frequent. The aim of this paper is to compare sixteen methods for handling the missing data (mainly based on simple imputation) in the context of psychometric validation of PRO by a Rasch model. The main indexes used for validation by a Rasch model are compared. Methods A simulation study was performed allowing to consider several cases, notably the possibility for the missing values to be informative or not and the rate of missing data. Results Several imputations methods produce bias on psychometrical indexes (generally, the imputation methods artificially improve the psychometric qualities of the scale). In particular, this is the case with the method based on the Personal Mean Score (PMS) which is the most commonly used imputation method in practice. Conclusions Several imputation methods should be avoided, in particular PMS imputation. From a general point of view, it is important to use an imputation method that considers both the ability of the patient (measured for example by his\\/her score), and the difficulty of the item (measured for example by its rate of favourable responses). Another recommendation is to always consider the addition of a random process in the imputation method, because such a process allows reducing the bias. Last, the analysis realized without imputation of the missing data (available case analyses) is an interesting alternative to the simple imputation in this context.

MMPM - Mars MetNet Precursor Mission

Science.gov (United States)

Harri, A.-M.; Schmidt, W.; Pichkhadze, K.; Linkin, V.; Vazquez, L.; Uspensky, M.; Polkko, J.; Genzer, M.; Lipatov, A.; Guerrero, H.; Alexashkin, S.; Haukka, H.; Savijarvi, H.; Kauhanen, J.

2008-09-01

We are developing a new kind of planetary exploration mission for Mars - MetNet in situ observation network based on a new semi-hard landing vehicle called the Met-Net Lander (MNL). The eventual scope of the MetNet Mission is to deploy some 20 MNLs on the Martian surface using inflatable descent system structures, which will be supported by observations from the orbit around Mars. Currently we are working on the MetNet Mars Precursor Mission (MMPM) to deploy one MetNet Lander to Mars in the 2009/2011 launch window as a technology and science demonstration mission. The MNL will have a versatile science payload focused on the atmospheric science of Mars. Detailed characterization of the Martian atmospheric circulation patterns, boundary layer phenomena, and climatology cycles, require simultaneous in-situ measurements by a network of observation posts on the Martian surface. The scientific payload of the MetNet Mission encompasses separate instrument packages for the atmospheric entry and descent phase and for the surface operation phase. The MetNet mission concept and key probe technologies have been developed and the critical subsystems have been qualified to meet the Martian environmental and functional conditions. Prototyping of the payload instrumentation with final dimensions was carried out in 2003-2006.This huge development effort has been fulfilled in collaboration between the Finnish Meteorological Institute (FMI), the Russian Lavoschkin Association (LA) and the Russian Space Research Institute (IKI) since August 2001. Currently the INTA (Instituto Nacional de Técnica Aeroespacial) from Spain is also participating in the MetNet payload development. To understand the behavior and dynamics of the Martian atmosphere, a wealth of simultaneous in situ observations are needed on varying types of Martian orography, terrain and altitude spanning all latitudes and longitudes. This will be performed by the Mars MetNet Mission. In addition to the science aspects the

MET gene exon 14 deletion created using the CRISPR/Cas9 system enhances cellular growth and sensitivity to a MET inhibitor.

Science.gov (United States)

Togashi, Yosuke; Mizuuchi, Hiroshi; Tomida, Shuta; Terashima, Masato; Hayashi, Hidetoshi; Nishio, Kazuto; Mitsudomi, Tetsuya

2015-12-01

MET splice site mutations resulting in an exon 14 deletion have been reported to be present in about 3% of all lung adenocarcinomas. Patients with lung adenocarcinoma and a MET splice site mutation who have responded to MET inhibitors have been reported. The CRISPR/Cas9 system is a recently developed genome-engineering tool that can easily and rapidly cause small insertions or deletions. We created an in vitro model for MET exon 14 deletion using the CRISPR/Cas9 system and the HEK293 cell line. The phenotype, which included MET inhibitor sensitivity, was then investigated in vitro. Additionally, MET splice site mutations were analyzed in several cancers included in The Cancer Genome Atlas (TCGA) dataset. An HEK293 cell line with a MET exon 14 deletion was easily and rapidly created; this cell line had a higher MET protein expression level, enhanced MET phosphorylation, and prolonged MET activation. In addition, a direct comparison of phenotypes using this system demonstrated enhanced cellular growth, colony formation, and MET inhibitor sensitivity. In the TCGA dataset, lung adenocarcinomas had the highest incidence of MET exon 14 deletions, while other cancers rarely carried such mutations. Approximately 10% of the lung adenocarcinoma samples without any of driver gene alterations carried the MET exon 14 deletion. These findings suggested that this system may be useful for experiments requiring the creation of specific mutations, and the present experimental findings encourage the development of MET-targeted therapy against lung cancer carrying the MET exon 14 deletion. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

The validity of a professional competence tool for physiotherapy students in simulation-based clinical education: a Rasch analysis.

Science.gov (United States)

Judd, Belinda K; Scanlan, Justin N; Alison, Jennifer A; Waters, Donna; Gordon, Christopher J

2016-08-05

Despite the recent widespread adoption of simulation in clinical education in physiotherapy, there is a lack of validated tools for assessment in this setting. The Assessment of Physiotherapy Practice (APP) is a comprehensive tool used in clinical placement settings in Australia to measure professional competence of physiotherapy students. The aim of the study was to evaluate the validity of the APP for student assessment in simulation settings. A total of 1260 APPs were collected, 971 from students in simulation and 289 from students in clinical placements. Rasch analysis was used to examine the construct validity of the APP tool in three different simulation assessment formats: longitudinal assessment over 1 week of simulation; longitudinal assessment over 2 weeks; and a short-form (25 min) assessment of a single simulation scenario. Comparison with APPs from 5 week clinical placements in hospital and clinic-based settings were also conducted. The APP demonstrated acceptable fit to the expectations of the Rasch model for the 1 and 2 week clinical simulations, exhibiting unidimensional properties that were able to distinguish different levels of student performance. For the short-form simulation, nine of the 20 items recorded greater than 25 % of scores as 'not-assessed' by clinical educators which impacted on the suitability of the APP tool in this simulation format. The APP was a valid assessment tool when used in longitudinal simulation formats. A revised APP may be required for assessment in short-form simulation scenarios.

Effects of the BDNF Val66Met polymorphism and met allele load on declarative memory related neural networks.

Science.gov (United States)

Dodds, Chris M; Henson, Richard N; Suckling, John; Miskowiak, Kamilla W; Ooi, Cinly; Tait, Roger; Soltesz, Fruzsina; Lawrence, Phil; Bentley, Graham; Maltby, Kay; Skeggs, Andrew; Miller, Sam R; McHugh, Simon; Bullmore, Edward T; Nathan, Pradeep J

2013-01-01

It has been suggested that the BDNF Val66Met polymorphism modulates episodic memory performance via effects on hippocampal neural circuitry. However, fMRI studies have yielded inconsistent results in this respect. Moreover, very few studies have examined the effect of met allele load on activation of memory circuitry. In the present study, we carried out a comprehensive analysis of the effects of the BDNF polymorphism on brain responses during episodic memory encoding and retrieval, including an investigation of the effect of met allele load on memory related activation in the medial temporal lobe. In contrast to previous studies, we found no evidence for an effect of BDNF genotype or met load during episodic memory encoding. Met allele carriers showed increased activation during successful retrieval in right hippocampus but this was contrast-specific and unaffected by met allele load. These results suggest that the BDNF Val66Met polymorphism does not, as previously claimed, exert an observable effect on neural systems underlying encoding of new information into episodic memory but may exert a subtle effect on the efficiency with which such information can be retrieved.

Effects of the BDNF Val66Met polymorphism and met allele load on declarative memory related neural networks.

Directory of Open Access Journals (Sweden)

Chris M Dodds

Full Text Available It has been suggested that the BDNF Val66Met polymorphism modulates episodic memory performance via effects on hippocampal neural circuitry. However, fMRI studies have yielded inconsistent results in this respect. Moreover, very few studies have examined the effect of met allele load on activation of memory circuitry. In the present study, we carried out a comprehensive analysis of the effects of the BDNF polymorphism on brain responses during episodic memory encoding and retrieval, including an investigation of the effect of met allele load on memory related activation in the medial temporal lobe. In contrast to previous studies, we found no evidence for an effect of BDNF genotype or met load during episodic memory encoding. Met allele carriers showed increased activation during successful retrieval in right hippocampus but this was contrast-specific and unaffected by met allele load. These results suggest that the BDNF Val66Met polymorphism does not, as previously claimed, exert an observable effect on neural systems underlying encoding of new information into episodic memory but may exert a subtle effect on the efficiency with which such information can be retrieved.

Fitting a Mixture Rasch Model to English as a Foreign Language Listening Tests: The Role of Cognitive and Background Variables in Explaining Latent Differential Item Functioning

Science.gov (United States)

Aryadoust, Vahid

2015-01-01

The present study uses a mixture Rasch model to examine latent differential item functioning in English as a foreign language listening tests. Participants (n = 250) took a listening and lexico-grammatical test and completed the metacognitive awareness listening questionnaire comprising problem solving (PS), planning and evaluation (PE), mental…

Gezondheidsrisico's in verband met het werken met Polychloorbifenylen : een onderzoek

NARCIS (Netherlands)

Geuskens, R.B.M.; Nossent, S.M.; Koëter, H.B.W.M.; Dreef-van der Meulen, H.C.; Stijkel, A.; Zielhuis, R.L.

1989-01-01

Met behulp van gegevens verkregen uit een werkplekinventarisatie naar gegevens over produktie/gebruik, risicopopulatie en (mogelijke) blootstelling aan polychloorbifenylen (PCB's), en een literatuurstudie naar mogelijke schadelijke eigenschappen van PCB's op het reproductiesysteem en/of nageslacht

The EGFR/ErbB3 Pathway Acts as a Compensatory Survival Mechanism upon c-Met Inhibition in Human c-Met+ Hepatocellular Carcinoma.

Directory of Open Access Journals (Sweden)

Steven N Steinway

Full Text Available c-Met, a high-affinity receptor for Hepatocyte Growth Factor (HGF, plays a critical role in tumor growth, invasion, and metastasis. Hepatocellular carcinoma (HCC patients with activated HGF/c-Met signaling have a significantly worse prognosis. Targeted therapies using c-Met tyrosine kinase inhibitors are currently in clinical trials for HCC, although receptor tyrosine kinase inhibition in other cancers has demonstrated early success. Unfortunately, therapeutic effect is frequently not durable due to acquired resistance.We utilized the human MHCC97-H c-Met positive (c-Met+ HCC cell line to explore the compensatory survival mechanisms that are acquired after c-Met inhibition. MHCC97-H cells with stable c-Met knockdown (MHCC97-H c-Met KD cells were generated using a c-Met shRNA vector with puromycin selection and stably transfected scrambled shRNA as a control. Gene expression profiling was conducted, and protein expression was analyzed to characterize MHCC97-H cells after blockade of the c-Met oncogene. A high-throughput siRNA screen was performed to find putative compensatory survival proteins, which could drive HCC growth in the absence of c-Met. Findings from this screen were validated through subsequent analyses.We have previously demonstrated that treatment of MHCC97-H cells with a c-Met inhibitor, PHA665752, results in stasis of tumor growth in vivo. MHCC97-H c-Met KD cells demonstrate slower growth kinetics, similar to c-Met inhibitor treated tumors. Using gene expression profiling and siRNA screening against 873 kinases and phosphatases, we identified ErbB3 and TGF-α as compensatory survival factors that are upregulated after c-Met inhibition. Suppressing these factors in c-Met KD MHCC97-H cells suppresses tumor growth in vitro. In addition, we found that the PI3K/Akt signaling pathway serves as a negative feedback signal responsible for the ErbB3 upregulation after c-Met inhibition. Furthermore, in vitro studies demonstrate that

Dual Regulation of Bacillus subtilis kinB Gene Encoding a Sporulation Trigger by SinR through Transcription Repression and Positive Stringent Transcription Control.

Science.gov (United States)

Fujita, Yasutaro; Ogura, Mitsuo; Nii, Satomi; Hirooka, Kazutake

2017-01-01

It is known that transcription of kinB encoding a trigger for Bacillus subtilis sporulation is under repression by SinR, a master repressor of biofilm formation, and under positive stringent transcription control depending on the adenine species at the transcription initiation nucleotide (nt). Deletion and base substitution analyses of the kinB promoter (P kinB ) region using lacZ fusions indicated that either a 5-nt deletion (Δ5, nt -61/-57, +1 is the transcription initiation nt) or the substitution of G at nt -45 with A (G-45A) relieved kinB repression. Thus, we found a pair of SinR-binding consensus sequences (GTTCTYT; Y is T or C) in an inverted orientation (SinR-1) between nt -57/-42, which is most likely a SinR-binding site for kinB repression. This relief from SinR repression likely requires SinI, an antagonist of SinR. Surprisingly, we found that SinR is essential for positive stringent transcription control of P kinB . Electrophoretic mobility shift assay (EMSA) analysis indicated that SinR bound not only to SinR-1 but also to SinR-2 (nt -29/-8) consisting of another pair of SinR consensus sequences in a tandem repeat arrangement; the two sequences partially overlap the '-35' and '-10' regions of P kinB . Introduction of base substitutions (T-27C C-26T) in the upstream consensus sequence of SinR-2 affected positive stringent transcription control of P kinB , suggesting that SinR binding to SinR-2 likely causes this positive control. EMSA also implied that RNA polymerase and SinR are possibly bound together to SinR-2 to form a transcription initiation complex for kinB transcription. Thus, it was suggested in this work that derepression of kinB from SinR repression by SinI induced by Spo0A∼P and occurrence of SinR-dependent positive stringent transcription control of kinB might induce effective sporulation cooperatively, implying an intimate interplay by stringent response, sporulation, and biofilm formation.

MET Expression in Primary and Metastatic Clear Cell Renal Cell Carcinoma: Implications of Correlative Biomarker Assessment to MET Pathway Inhibitors

Directory of Open Access Journals (Sweden)

Brian Shuch

2015-01-01

Full Text Available Aims. Inhibitors of the MET pathway hold promise in the treatment for metastatic kidney cancer. Assessment of predictive biomarkers may be necessary for appropriate patient selection. Understanding MET expression in metastases and the correlation to the primary site is important, as distant tissue is not always available. Methods and Results. MET immunofluorescence was performed using automated quantitative analysis and a tissue microarray containing matched nephrectomy and distant metastatic sites from 34 patients with clear cell renal cell carcinoma. Correlations between MET expressions in matched primary and metastatic sites and the extent of heterogeneity were calculated. The mean expression of MET was not significantly different between primary tumors when compared to metastases (P=0.1. MET expression weakly correlated between primary and matched metastatic sites (R=0.5 and a number of cases exhibited very high levels of discordance between these tumors. Heterogeneity within nephrectomy specimens compared to the paired metastatic tissues was not significantly different (P=0.39. Conclusions. We found that MET expression is not significantly different in primary tumors than metastatic sites and only weakly correlates between matched sites. Moderate concordance of MET expression and significant expression heterogeneity may be a barrier to the development of predictive biomarkers using MET targeting agents.

COMT (Val158Met and BDNF (Val66Met Genes Polymorphism in Schizophrenia: A Case-Control Report

Directory of Open Access Journals (Sweden)

ramin saravani

2017-10-01

Full Text Available Objective: The effects of human brain-derived neurotropic factor (BDNF Val66Met (G>A and the human Catechol-O-methylTransferase (COMT Val158Met (G>A polymorphisms on Schizophrenia (SCZ risk were evaluated.Methods: This case control study included 92 SCZ patients and 92 healthy controls (HCs. Genotyping of both variants were conducted using Amplification Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR.Results: The findings showed that BDNF Val66Met (G>A variant increased the risk of SCZ (OR=2.008 95%CI=1.008-4.00, P=0.047, GA vs. GG, OR=3.876 95%CI=1.001-14.925, P=0.049. AA vs. GG, OR=2.272. 95%CI=1.204-4.347, P=0.011, GA+AA vs. GG, OR=2.22 95%CI=1.29-3.82. P=0.005, A vs. G. COMT Val158Met (G>A polymorphism was not associated with the risk/protective of SCZ.Conclusion: The results proposed that BDNF Val66Met (G>A polymorphism may increase the risk of SCZ development and did not support an association between COMT Val158Met (G>A variant and risk/protective of SCZ. Further studies and different ethnicities are recommended to confirm the findings.

Mars MetNet Precursor Mission Status

Science.gov (United States)

Harri, A.-M.; Aleksashkin, S.; Guerrero, H.; Schmidt, W.; Genzer, M.; Vazquez, L.; Haukka, H.

2013-09-01

We are developing a new kind of planetary exploration mission for Mars in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semi-hard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested.

Rasch Validation and Cross-validation of the Health of Nation Outcome Scales (HoNOS) for Monitoring of Psychiatric Disability in Traumatized Refugees in Western Psychiatric Care

DEFF Research Database (Denmark)

Palic, Sabina; Kappel, Michelle Lind; Makransky, Guido

2016-01-01

group. A revised 10-item HoNOS fit the Rasch model at pre-treatment, and also showed excellent fit within the cross-validation data. Culture, gender, and need for translation did not exert serious bias on the measure’s performance. The results establish good monitoring properties of the 10-item Ho...

Targeting MET Amplification as a New Oncogenic Driver

International Nuclear Information System (INIS)

Kawakami, Hisato; Okamoto, Isamu; Okamoto, Wataru; Tanizaki, Junko; Nakagawa, Kazuhiko; Nishio, Kazuto

2014-01-01

Certain genetically defined cancers are dependent on a single overactive oncogene for their proliferation and survival, a phenomenon known as “oncogene addiction”. A new generation of drugs that selectively target such “driver oncogenes” manifests a clinical efficacy greater than that of conventional chemotherapy in appropriate genetically defined patients. MET is a proto-oncogene that encodes a receptor tyrosine kinase, and aberrant activation of MET signaling occurs in a subset of advanced cancers as result of various genetic alterations including gene amplification, polysomy, and gene mutation. Our preclinical studies have shown that inhibition of MET signaling either with the small-molecule MET inhibitor crizotinib or by RNA interference targeted to MET mRNA resulted in marked antitumor effects in cancer cell lines with MET amplification both in vitro and in vivo. Furthermore, patients with non-small cell lung cancer or gastric cancer positive for MET amplification have shown a pronounced clinical response to crizotinib. Accumulating preclinical and clinical evidence thus suggests that MET amplification is an “oncogenic driver” and therefore a valid target for treatment. However, the prevalence of MET amplification has not been fully determined, possibly in part because of the difficulty in evaluating gene amplification. In this review, we provide a rationale for targeting this genetic alteration in cancer therapy

Targeting MET Amplification as a New Oncogenic Driver

Energy Technology Data Exchange (ETDEWEB)

Kawakami, Hisato [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Okamoto, Isamu, E-mail: okamotoi@kokyu.med.kyushu-u.ac.jp [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Center for Clinical and Translational Research, Kyushu University Hospital, 3-1-1 Maidashi, Higashiku, Fukuoka 812-8582 (Japan); Okamoto, Wataru [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Division of Transrlational Research, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 6-5-1 Kashiwanoha, Kashiwa, Chiba 277-8577 (Japan); Tanizaki, Junko [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Lowe Center for Thoracic Oncology, Dana-Farber Cancer Institute, HIM223, 450 Brookline Avenue, Boston, MA 02215 (United States); Nakagawa, Kazuhiko [Department of Medical Oncology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan); Nishio, Kazuto [Department of Genome Biology, Kinki University Faculty of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka 589-8511 (Japan)

2014-07-22

Certain genetically defined cancers are dependent on a single overactive oncogene for their proliferation and survival, a phenomenon known as “oncogene addiction”. A new generation of drugs that selectively target such “driver oncogenes” manifests a clinical efficacy greater than that of conventional chemotherapy in appropriate genetically defined patients. MET is a proto-oncogene that encodes a receptor tyrosine kinase, and aberrant activation of MET signaling occurs in a subset of advanced cancers as result of various genetic alterations including gene amplification, polysomy, and gene mutation. Our preclinical studies have shown that inhibition of MET signaling either with the small-molecule MET inhibitor crizotinib or by RNA interference targeted to MET mRNA resulted in marked antitumor effects in cancer cell lines with MET amplification both in vitro and in vivo. Furthermore, patients with non-small cell lung cancer or gastric cancer positive for MET amplification have shown a pronounced clinical response to crizotinib. Accumulating preclinical and clinical evidence thus suggests that MET amplification is an “oncogenic driver” and therefore a valid target for treatment. However, the prevalence of MET amplification has not been fully determined, possibly in part because of the difficulty in evaluating gene amplification. In this review, we provide a rationale for targeting this genetic alteration in cancer therapy.

Mars MetNet Mission Payload Overview

Science.gov (United States)

Harri, A.-M.; Haukka, H.; Alexashkin, S.; Guerrero, H.; Schmidt, W.; Genzer, M.; Vazquez, L.

2012-09-01

A new kind of planetary exploration mission for Mars is being developed in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission [1] is based on a new semi-hard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide crucial scientific data about the Martian atmospheric phenomena.

Stringent limits on the ionized mass loss from A and F dwarfs

International Nuclear Information System (INIS)

Brown, A.; Veale, A.; Judge, P.; Bookbinder, J.A.; Hubeny, I.

1990-01-01

Following the suggestion of Willson et al. (1987) that A- and F-type main-sequence stars might undergo significant mass loss due to pulsationally driven winds, upper limits to the ionized mass loss from A and F dwarfs have been obtained using VLA observations. These stringent upper limits show that the level of ionized mass loss would have at most only a small effect on stellar evolution. Radiative-equilibrium atmospheric and wind models for early A dwarfs indicate that it is highly likely that a wind flowing from such stars would be significantly ionized. In addition, late A and early F dwarfs exhibit chromospheric emission indicative of significant nonradiative heating. The present mass-loss limits are thus representative of the total mass-loss rates for these stars. It is concluded that A and F dwarfs are not losing sufficient mass to cause A dwarfs to evolve into G dwarfs. 24 refs

Ervaringen met beeldverwerking.

NARCIS (Netherlands)

Meuleman, J.

1989-01-01

Verslag van een werkbezoek aan het Franse instituut Cemagref, met nadruk op beeldverwerking. Toepassingen van beeldverwerking zijn onder andere: een plukrobot voor appels; het detecteren van oppervlaktebeschadigingen bij appels; het detecteren van breuk in eieren; remote sensing

Rasch modeling of the Spanish self-report version of the Liebowitz Social Anxiety Scale for Children and Adolescents (LSAS-CA-SR

Directory of Open Access Journals (Sweden)

José A. López-Pina

2008-01-01

Full Text Available El objetivo de este estudio instrumental fue analizar la estructura unidimensional de las subescalas de miedo y evitación de la versión española de la escala de ansiedad social LSAS-CA-SR para niños y adolescentes bajo la familia de modelos de Rasch. La muestra estuvo formada por 454 estudiantes (236 varones y 218 mujeres de educación primaria y secundaria cuya edad variaba entre 10 y 17 años. El modelo de escalas de valoración fue ajustado a los datos de ambas subescalas. Los estadísticos de ajuste (media cuadrática ponderada y media cuadrática no ponderada mostraron un buen ajuste de los ítems al modelo, excepto en los ítems 10 y 16 en la subescala de miedo, y los ítems 6, 7 y 21 en la subescala de evitación. Además, la subdivisión de la muestra global en dos submuestras aleatorias de 150 personas probó que el modelo de escalas de valoración produjo un ordenamiento invariante de los parámetros de los ítems y de los parámetros de las personas. Este estudio respalda, así, la utilidad del modelo de Rasch y su familia para determinar la unidimensionalidad en un test psicológico.

Development of a Microsoft Excel tool for one-parameter Rasch model of continuous items: an application to a safety attitude survey.

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Chien, Tsair-Wei; Shao, Yang; Kuo, Shu-Chun

2017-01-10

Many continuous item responses (CIRs) are encountered in healthcare settings, but no one uses item response theory's (IRT) probabilistic modeling to present graphical presentations for interpreting CIR results. A computer module that is programmed to deal with CIRs is required. To present a computer module, validate it, and verify its usefulness in dealing with CIR data, and then to apply the model to real healthcare data in order to show how the CIR that can be applied to healthcare settings with an example regarding a safety attitude survey. Using Microsoft Excel VBA (Visual Basic for Applications), we designed a computer module that minimizes the residuals and calculates model's expected scores according to person responses across items. Rasch models based on a Wright map and on KIDMAP were demonstrated to interpret results of the safety attitude survey. The author-made CIR module yielded OUTFIT mean square (MNSQ) and person measures equivalent to those yielded by professional Rasch Winsteps software. The probabilistic modeling of the CIR module provides messages that are much more valuable to users and show the CIR advantage over classic test theory. Because of advances in computer technology, healthcare users who are familiar to MS Excel can easily apply the study CIR module to deal with continuous variables to benefit comparisons of data with a logistic distribution and model fit statistics.

Alkaline transition of pseudoazurin Met16X mutant proteins: protein stability influenced by the substitution of Met16 in the second sphere coordination.

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Abdelhamid, Rehab F; Obara, Yuji; Kohzuma, Takamitsu

2008-01-01

Several blue copper proteins are known to change the active site structure at alkaline pH (alkaline transition). Spectroscopic studies of Met16Phe, Met16Tyr, Met16Trp, and Met16Val pseudoazurin variants were performed to investigate the second sphere role through alkaline transition. The visible electronic absorption and resonance Raman spectra of Met16Phe, Met16Tyr, and Met16Trp variants showed the increasing of axial component at pH approximately 11 like wild-type PAz. The visible electronic absorption and far-UV CD spectra of Met16Val demonstrated that the destabilization of the protein structure was triggered at pH>11. Resonance Raman (RR) spectra of PAz showed that the intensity-weighted averaged Cu-S(Cys) stretching frequency was shifted to higher frequency region at pH approximately 11. The higher frequency shift of Cu-S(Cys) bond is implied the stronger Cu-S(Cys) bond at alkaline transition pH approximately 11. The visible electronic absorption and far-UV CD spectra of Met16X PAz revealed that the Met16Val variant is denatured at pH>11, but Met16Phe, Met16Tyr, and Met16Trp mutant proteins are not denatured even at pH>11. These observations suggest that Met16 is important to maintain the protein structure through the possible weak interaction between methionine -SCH3 part and coordinated histidine imidazole moiety. The introduction of pi-pi interaction in the second coordination sphere may be contributed to the enhancement of protein structure stability.

Autorijden met ADHD

NARCIS (Netherlands)

Fuermaier, Anselm B.M.; Tucha, Lara; de Vries, Stefanie M.; Koerts, Janneke; de Waard, Dick; Brookhuis, Karel; Tucha, Oliver

Volwassenen met attention deficit hyperactivity disorder (ADHD) hebben uiteenlopende cognitieve beperkingen, die een aanzienlijke invloed kunnen hebben op verschillende aspecten van het dagelijks leven. Een van deze aspecten is het besturen van een auto. Autorijden is een belangrijke activiteit in

Classical test theory and Rasch analysis validation of the Upper Limb Functional Index in subjects with upper limb musculoskeletal disorders.

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Bravini, Elisabetta; Franchignoni, Franco; Giordano, Andrea; Sartorio, Francesco; Ferriero, Giorgio; Vercelli, Stefano; Foti, Calogero

2015-01-01

To perform a comprehensive analysis of the psychometric properties and dimensionality of the Upper Limb Functional Index (ULFI) using both classical test theory and Rasch analysis (RA). Prospective, single-group observational design. Freestanding rehabilitation center. Convenience sample of Italian-speaking subjects with upper limb musculoskeletal disorders (N=174). Not applicable. The Italian version of the ULFI. Data were analyzed using parallel analysis, exploratory factor analysis, and RA for evaluating dimensionality, functioning of rating scale categories, item fit, hierarchy of item difficulties, and reliability indices. Parallel analysis revealed 2 factors explaining 32.5% and 10.7% of the response variance. RA confirmed the failure of the unidimensionality assumption, and 6 items out of the 25 misfitted the Rasch model. When the analysis was rerun excluding the misfitting items, the scale showed acceptable fit values, loading meaningfully to a single factor. Item separation reliability and person separation reliability were .98 and .89, respectively. Cronbach alpha was .92. RA revealed weakness of the scale concerning dimensionality and internal construct validity. However, a set of 19 ULFI items defined through the statistical process demonstrated a unidimensional structure, good psychometric properties, and clinical meaningfulness. These findings represent a useful starting point for further analyses of the tool (based on modern psychometric approaches and confirmatory factor analysis) in larger samples, including different patient populations and nationalities. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Research progress in c-Met and hepatocellular carcinoma

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WANG Changqing

2015-06-01

Full Text Available c-Met plays a pivotal role in the development and progression of hepatocellular carcinoma (HCC, which can lead to proliferation, survival, cytoskeleton reorganization, separation and diffusion, and angiogenesis of tumor cells. Moreover, c-Met is an important prognostic factor for HCC. In HCC, c-Met acts as an activator of a series of signaling pathways, including PI3K/AKT/mTOR, ERK/MAPK, and Rac-Pak. In recent years, it has been reported that small-molecule kinase inhibitors can abolish phosphorylation at the intracellular carboxyl terminal of c-Met, and then inhibit the recruitment of signal convertors and downstream signaling pathways, which finally achieve anti-tumor activities. Based on the carcinogenic activity of c-Met in HCC, this paper points out that selective inhibitors of c-Met hold promise for targeted therapies for HCC.

Validity study of the Beck Anxiety Inventory (Portuguese version by the Rasch Rating Scale model

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Sónia Quintão

2013-01-01

Full Text Available Our objective was to conduct a validation study of the Portuguese version of the Beck Anxiety Inventory (BAI by means of the Rasch Rating Scale Model, and then compare it with the most used scales of anxiety in Portugal. The sample consisted of 1,160 adults (427 men and 733 women, aged 18-82 years old (M=33.39; SD=11.85. Instruments were Beck Anxiety Inventory, State-Trait Anxiety Inventory and Zung Self-Rating Anxiety Scale. It was found that Beck Anxiety Inventory's system of four categories, the data-model fit, and people reliability were adequate. The measure can be considered as unidimensional. Gender and age-related differences were not a threat to the validity. BAI correlated significantly with other anxiety measures. In conclusion, BAI shows good psychometric quality.

The Reliability and Validity of the Power-Load-Margin Inventory: A Rasch Analysis.

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Hardigan, Patrick C; Cohen, Stanley R; Hagen, Kathleen P

2015-01-01

Margin is a function of the relationship of stress to strength. The greater the margin, the more likely students are able to successfully navigate academic structures. This study examined the psychometric properties of a newly created instrument designed to measure margin - the Power-Load-Margin Inventory (PLMI). The PLMI was created using eight domains: (A) Student's aptitude and ability, (B) Course structure, (C) External motivation, (D) Student health, (E) Instructor style, (F) Internal motivation, (G) Life opportunities, and (H) University support structure. A three-point response scale was used to measure the domains: (1) stress, (2) neither stress nor strength, and (3) strength. The PLMI was administered to 586 medical, dental, and pharmacy students. A Rasch rating scale model was used to examine the psychometric properties of the PLMI. The PLMI demonstrated acceptable psychometric properties for use with pharmacy, dental, and medical students. The PLMI's primary weakness was with the subscales' reliability. We attribute this to the small number of items per subscale.

The nutrition for sport knowledge questionnaire (NSKQ): development and validation using classical test theory and Rasch analysis.

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Trakman, Gina Louise; Forsyth, Adrienne; Hoye, Russell; Belski, Regina

2017-01-01

Appropriate dietary intake can have a significant influence on athletic performance. There is a growing consensus on sports nutrition and professionals working with athletes often provide dietary education. However, due to the limitations of existing sports nutrition knowledge questionnaires, previous reports of athletes' nutrition knowledge may be inaccurate. An updated questionnaire has been developed based on a recent review of sports nutrition guidelines. The tool has been validated using a robust methodology that incorporates relevant techniques from classical test theory (CTT) and Item response theory (IRT), namely, Rasch analysis. The final questionnaire has 89 questions and six sub-sections (weight management, macronutrients, micronutrients, sports nutrition, supplements, and alcohol). The content and face validity of the tool have been confirmed based on feedback from expert sports dietitians and university sports students, respectively. The internal reliability of the questionnaire as a whole is high (KR = 0.88), and most sub-sections achieved an acceptable internal reliability. Construct validity has been confirmed, with an independent T-test revealing a significant ( p  < 0.001) difference in knowledge scores of nutrition (64 ± 16%) and non-nutrition students (51 ± 19%). Test-retest reliability has been assured, with a strong correlation ( r  = 0.92, p  < 0.001) between individuals' scores on two attempts of the test, 10 days to 2 weeks apart. Three of the sub-sections fit the Rasch Unidimensional Model. The final version of the questionnaire represents a significant improvement over previous tools. Each nutrition sub-section is unidimensional, and therefore researchers and practitioners can use these individually, as required. Use of the questionnaire will allow researchers to draw conclusions about the effectiveness of nutrition education programs, and differences in knowledge across athletes of varying ages, genders, and athletic

Utilizing Multifaceted Rasch Measurement through Facets to Evaluate Science Education Data Sets Composed of Judges, Respondents, and Rating Scale Items: An Exemplar Utilizing the Elementary Science Teaching Analysis Matrix Instrument

Science.gov (United States)

Boone, William J.; Townsend, J. Scott; Staver, John R.

2016-01-01

When collecting data, science education researchers frequently have multiple respondents evaluate multiple artifacts using multiple criteria. Herein, the authors introduce Multifaceted Rasch Measurement (MFRM) analysis and explain why MFRM must be used when "judges'" data are collected. The authors use data from elementary science…

MET amplification, expression, and exon 14 mutations in colorectal adenocarcinoma.

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Zhang, Meng; Li, Guichao; Sun, Xiangjie; Ni, Shujuan; Tan, Cong; Xu, Midie; Huang, Dan; Ren, Fei; Li, Dawei; Wei, Ping; Du, Xiang

2018-04-08

MET amplification, expression, and splice mutations at exon 14 result in dysregulation of the MET signaling pathway. The aim of this study was to identify the relationship between MET amplification, protein or mRNA expression, and mutations in colorectal cancer (CRC). MET immunohistochemistry (IHC) was used for MET protein expression analysis and fluorescence in situ hybridization (FISH) was used for MET amplification detection. Both analyses were performed in tissue microarrays (TMA) containing 294 of colorectal adenocarcinoma tissue samples and 131 samples of adjacent normal epithelial tissue. MET mRNA expression was examined by real-time quantitative polymerase chain reaction (qRT-PCR) in 72 fresh colorectal adenocarcinoma tissue samples and adjacent normal colon tissue. PCR sequencing was performed to screen for MET exon 14 splice mutations in 59 fresh CRC tissue samples. Our results showed that MET protein expression was higher in colorectal tumor tissue than in adjacent normal intestinal epithelium. Positive MET protein expression was associated with significantly poorer overall survival (OS) and disease-free survival (DFS). Multivariate analysis revealed that positive MET protein expression was an independent risk factor for DFS, but not for OS. MET mRNA expression was upregulated in tumor tissues compared with the adjacent normal tissues. The incidence of MET amplification was 4.4%. None of the patients was positive for MET mutation. Collectively, MET was overexpressed in colorectal adenocarcinoma, and its positive protein expression predicted a poorer outcome in CRC patients. Furthermore, according to our results, MET amplification and 14 exon mutation are extremely rare events in colorectal adenocarcinoma. Copyright © 2018. Published by Elsevier Inc.

Whole-Genome Microarray and Gene Deletion Studies Reveal Regulation of the Polyhydroxyalkanoate Production Cycle by the Stringent Response in Ralstonia eutropha H16

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Brigham, CJ; Speth, DR; Rha, C; Sinskey, AJ

2012-10-22

Poly(3-hydroxybutyrate) (PHB) production and mobilization in Ralstonia eutropha are well studied, but in only a few instances has PHB production been explored in relation to other cellular processes. We examined the global gene expression of wild-type R. eutropha throughout the PHB cycle: growth on fructose, PHB production using fructose following ammonium depletion, and PHB utilization in the absence of exogenous carbon after ammonium was resupplied. Our results confirm or lend support to previously reported results regarding the expression of PHB-related genes and enzymes. Additionally, genes for many different cellular processes, such as DNA replication, cell division, and translation, are selectively repressed during PHB production. In contrast, the expression levels of genes under the control of the alternative sigma factor sigma(54) increase sharply during PHB production and are repressed again during PHB utilization. Global gene regulation during PHB production is strongly reminiscent of the gene expression pattern observed during the stringent response in other species. Furthermore, a ppGpp synthase deletion mutant did not show an accumulation of PHB, and the chemical induction of the stringent response with DL-norvaline caused an increased accumulation of PHB in the presence of ammonium. These results indicate that the stringent response is required for PHB accumulation in R. eutropha, helping to elucidate a thus-far-unknown physiological basis for this process.

Jeugd met beperkingen

NARCIS (Netherlands)

Sjoerd Kooiker

2006-01-01

Voor kinderen en jongeren met een lichamelijke of verstandelijke beperking is 'gewoon meedoen' in de samenleving geen vanzelfsprekendheid.  Zij ervaren vaak meer obstakels bij het naar school gaan, het vinden van een baan en in hun vrijetijdsbesteding dan andere kinderen en jongeren. Ook

SPSS met syntax

NARCIS (Netherlands)

Grotenhuis, H.F. te; Visscher, C.A.M.

2007-01-01

Dit boekje wijkt af van de gebruikelijke statistiekboeken omdat het sec gaat over het bekende statistische computerprogramma SPSS, en dan alleen nog de oorspronkelijke variant waarin wordt gewerkt met syntax (intypen commando's -zoals bij DOS) i.p.v. de later ontwikkelde 'Windows-schil' (aanklikken

PHA665752, a small-molecule inhibitor of c-Met, inhibits hepatocyte growth factor-stimulated migration and proliferation of c-Met-positive neuroblastoma cells

International Nuclear Information System (INIS)

Crosswell, Hal E; Dasgupta, Anindya; Alvarado, Carlos S; Watt, Tanya; Christensen, James G; De, Pradip; Durden, Donald L; Findley, Harry W

2009-01-01

c-Met is a tyrosine kinase receptor for hepatocyte growth factor/scatter factor (HGF/SF), and both c-Met and its ligand are expressed in a variety of tissues. C-Met/HGF/SF signaling is essential for normal embryogenesis, organogenesis, and tissue regeneration. Abnormal c-Met/HGF/SF signaling has been demonstrated in different tumors and linked to aggressive and metastatic tumor phenotypes. In vitro and in vivo studies have demonstrated inhibition of c-Met/HGF/SF signaling by the small-molecule inhibitor PHA665752. This study investigated c-Met and HGF expression in two neuroblastoma (NBL) cell lines and tumor tissue from patients with NBL, as well as the effects of PHA665752 on growth and motility of NBL cell lines. The effect of the tumor suppressor protein PTEN on migration and proliferation of tumor cells treated with PHA665752 was also evaluated. Expression of c-Met and HGF in NBL cell lines SH-EP and SH-SY5Y and primary tumor tissue was assessed by immunohistochemistry and quantitative RT-PCR. The effect of PHA665752 on c-Met/HGF signaling involved in NBL cell proliferation and migration was evaluated in c-Met-positive cells and c-Met-transfected cells. The transwell chemotaxis assay and the MTT assay were used to measure migration and proliferation/cell-survival of tumor cells, respectively. The PPAR-γ agonist rosiglitazone was used to assess the effect of PTEN on PHA665752-induced inhibition of NBL cell proliferation/cell-survival and migration High c-Met expression was detected in SH-EP cells and primary tumors from patients with advanced-stage disease. C-Met/HGF signaling induced both migration and proliferation of SH-EP cells. Migration and proliferation/cell-survival were inhibited by PHA665752 in a dose-dependent manner. We also found that induced overexpression of PTEN following treatment with rosiglitazone significantly enhanced the inhibitory effect of PHA665752 on NBL-cell migration and proliferation. c-Met is highly expressed in most tumors from

City-specific vehicle emission control strategies to achieve stringent emission reduction targets in China's Yangtze River Delta region.

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Zhang, Shaojun; Wu, Ye; Zhao, Bin; Wu, Xiaomeng; Shu, Jiawei; Hao, Jiming

2017-01-01

The Yangtze River Delta (YRD) region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality. Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants (e.g., CO, HC and PM 2.5 ) in the YRD region. Even in Shanghai, where the emission control implemented are more stringent than in Jiangsu and Zhejiang, we observed little to no reduction in NOx emissions from 2000 to 2010. Emission-reduction targets for HC, NOx and PM 2.5 are determined using a response surface modeling tool for better air quality. We design city-specific emission control strategies for three vehicle-populated cities in the YRD region: Shanghai and Nanjing and Wuxi in Jiangsu. Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards, the limitation of vehicle population and usage, and the scrappage of older vehicles is applied, Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020. Therefore, additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles. Copyright © 2016. Published by Elsevier B.V.

Achieving stringent climate targets. An analysis of the role of transport and variable renewable energies using energy-economy-climate models

Energy Technology Data Exchange (ETDEWEB)

Pietzcker, Robert Carl

2014-07-01

Anthropogenic climate change is threatening the welfare of mankind. Accordingly, policy makers have repeatedly stated the goal of slowing climate change and limiting the increase of global mean temperature to less than 2 C above pre-industrial times (the so-called ''two degree target''). Stabilizing the temperature requires drastic reductions of greenhouse gas (GHG) emissions to nearly zero. As the global system of energy supply currently relies on fossil fuels, reducing GHG emissions can only be achieved through a full-scale transformation of the energy system. This thesis investigates the economic requirements and implications of different scenarios that achieve stringent climate mitigation targets. It starts with the analysis of characteristic decarbonization patterns and identifies two particularly relevant aspects of mitigation scenarios: deployment of variable renewable energies (VRE) and decarbonization of the transport sector. After investigating these fields in detail, we turned towards one of the most relevant questions for policy makers and analyzed the trade-off between the stringency of a climate target and its economic requirements and implications. All analyses are based on the improvement, application, comparison, and discussion of large-scale IAMs. The novel ''mitigation share'' metric allowed us to identify the relevance of specific technology groups for mitigation and to improve our understanding of the decarbonization patterns of different energy subsectors. It turned out that the power sector is decarbonized first and reaches lowest emissions, while the transport sector is slowest to decarbonize. For the power sector, non-biomass renewable energies contribute most to emission reductions, while the transport sector strongly relies on liquid fuels and therefore requires biomass in combination with carbon capture and sequestration (CCS) to reduce emissions. An in-depth investigation of the solar power

Dissection of combinatorial control by the Met4 transcriptional complex.

Science.gov (United States)

Lee, Traci A; Jorgensen, Paul; Bognar, Andrew L; Peyraud, Caroline; Thomas, Dominique; Tyers, Mike

2010-02-01

Met4 is the transcriptional activator of the sulfur metabolic network in Saccharomyces cerevisiae. Lacking DNA-binding ability, Met4 must interact with proteins called Met4 cofactors to target promoters for transcription. Two types of DNA-binding cofactors (Cbf1 and Met31/Met32) recruit Met4 to promoters and one cofactor (Met28) stabilizes the DNA-bound Met4 complexes. To dissect this combinatorial system, we systematically deleted each category of cofactor(s) and analyzed Met4-activated transcription on a genome-wide scale. We defined a core regulon for Met4, consisting of 45 target genes. Deletion of both Met31 and Met32 eliminated activation of the core regulon, whereas loss of Met28 or Cbf1 interfered with only a subset of targets that map to distinct sectors of the sulfur metabolic network. These transcriptional dependencies roughly correlated with the presence of Cbf1 promoter motifs. Quantitative analysis of in vivo promoter binding properties indicated varying levels of cooperativity and interdependency exists between members of this combinatorial system. Cbf1 was the only cofactor to remain fully bound to target promoters under all conditions, whereas other factors exhibited different degrees of regulated binding in a promoter-specific fashion. Taken together, Met4 cofactors use a variety of mechanisms to allow differential transcription of target genes in response to various cues.

Innoveren met serious games : Wat is serious gaming?

NARCIS (Netherlands)

Werkhoven, P.J.

2008-01-01

Het begrip serious gaming is inmiddels gekaapt door vele aanbieders van wat vroeger simulatie en virtual reality technologie genoemd werd. Met die technologie kunnen we mensen laten rondlopen in virtuele gebouwen en landschappen, al dan niet met grote projectieschermen of met brillen op. Maar dat is

Measuring students' perceptions of plagiarism: modification and Rasch validation of a plagiarism attitude scale.

Science.gov (United States)

Howard, Steven J; Ehrich, John F; Walton, Russell

2014-01-01

Plagiarism is a significant area of concern in higher education, given university students' high self-reported rates of plagiarism. However, research remains inconsistent in prevalence estimates and suggested precursors of plagiarism. This may be a function of the unclear psychometric properties of the measurement tools adopted. To investigate this, we modified an existing plagiarism scale (to broaden its scope), established its psychometric properties using traditional (EFA, Cronbach's alpha) and modern (Rasch analysis) survey evaluation approaches, and examined results of well-functioning items. Results indicated that traditional and modern psychometric approaches differed in their recommendations. Further, responses indicated that although most respondents acknowledged the seriousness of plagiarism, these attitudes were neither unanimous nor consistent across the range of issues assessed. This study thus provides rigorous psychometric testing of a plagiarism attitude scale and baseline data from which to begin a discussion of contextual, personal, and external factors that influence students' plagiarism attitudes.

Rasch Analysis of the Premature Ejaculation Diagnostic Tool (PEDT and the International Index of Erectile Function (IIEF in an Iranian Sample of Prostate Cancer Patients.

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Chung-Ying Lin

Full Text Available Male sexual dysfunction is an increasing problem across a variety of general and clinical populations, such as cancer populations; especially among prostate cancer patients who tend to receive treatments that often result in erectile dysfunction (ED and/or premature ejaculation (PE. Therefore, in order to diagnose ED and PE in these populations, adequate and efficient instruments such as the International Index of Erectile Function 5-item version (IIEF-5 and the Premature Ejaculation Diagnostic Tool (PEDT are needed. However, since this is an important topic additional evidence of psychometric properties of the IIEF-5 and the PEDT in such samples are required. Thus the aim of the present study was to use Rasch models to investigate the construct validity, local dependency, score order, and differential item functioning (DIF of both questionnaires in a sample of prostate cancer patients.Prostate cancer patients (n = 1058, mean±SD age = 64.07±6.84 years who visited urology clinics were invited to fill out the IIEF-5 and the PEDT. Construct validity was examined using infit and outfit mean square (MnSq and local dependency using correlations between each two residual Rasch scores. Score order was investigated using step and average measures of difficulty and DIF using DIF contrast.All IIEF-5 and PEDT items had acceptable infit and outfit MnSq. Step measures revealed that all but two items had disordered categories in terms of scores 1 to 3. Only one local dependency was found, and no items displayed DIF across age, educational level, and help seeking.The results showed that both the IIEF-5 and the PEDT had sound psychometric properties in the Rasch analyses, although some score disordering could be detected in both instruments. The results of no DIF items in both instruments suggest using them to compare ED and PE across age and educational level is adequate.

Rasch analysis of the Mini-Mental Adjustment to Cancer Scale (mini-MAC) among a heterogeneous sample of long-term cancer survivors: a cross-sectional study.

Science.gov (United States)

Zucca, Alison; Lambert, Sylvie D; Boyes, Allison W; Pallant, Julie F

2012-05-20

The mini-Mental Adjustment to Cancer Scale (mini-MAC) is a well-recognised, popular measure of coping in psycho-oncology and assesses five cancer-specific coping strategies. It has been suggested that these five subscales could be grouped to form the over-arching adaptive and maladptive coping subscales to facilitate the interpretation and clinical application of the scale. Despite the popularity of the mini-MAC, few studies have examined its psychometric properties among long-term cancer survivors, and further validation of the mini-MAC is needed to substantiate its use with the growing population of survivors. Therefore, this study examined the psychometric properties and dimensionality of the mini-MAC in a sample of long-term cancer survivors using Rasch analysis. RUMM 2030 was used to analyse the mini-MAC data (n=851). Separate Rasch analyses were conducted for each of the original mini-MAC subscales as well as the over-arching adaptive and maladaptive coping subscales to examine summary and individual model fit statistics, person separation index (PSI), response format, local dependency, targeting, item bias (or differential item functioning -DIF), and dimensionality. For the fighting spirit, fatalism, and helplessness-hopelessness subscales, a revised three-point response format seemed more optimal than the original four-point response. To achieve model fit, items were deleted from four of the five subscales - Anxious Preoccupation items 7, 25, and 29; Cognitive Avoidance items 11 and 17; Fighting Spirit item 18; and Helplessness-Hopelessness items 16 and 20. For those subscales with sufficient items, analyses supported unidimensionality. Combining items to form the adaptive and maladaptive subscales was partially supported. The original five subscales required item deletion and/or rescaling to improve goodness of fit to the Rasch model. While evidence was found for overarching subscales of adaptive and maladaptive coping, extensive modifications were

Rasch analysis of the Mini-Mental Adjustment to Cancer Scale (mini-MAC among a heterogeneous sample of long-term cancer survivors: A cross-sectional study

Directory of Open Access Journals (Sweden)

Zucca Alison

2012-05-01

Full Text Available Abstract Background The mini-Mental Adjustment to Cancer Scale (mini-MAC is a well-recognised, popular measure of coping in psycho-oncology and assesses five cancer-specific coping strategies. It has been suggested that these five subscales could be grouped to form the over-arching adaptive and maladptive coping subscales to facilitate the interpretation and clinical application of the scale. Despite the popularity of the mini-MAC, few studies have examined its psychometric properties among long-term cancer survivors, and further validation of the mini-MAC is needed to substantiate its use with the growing population of survivors. Therefore, this study examined the psychometric properties and dimensionality of the mini-MAC in a sample of long-term cancer survivors using Rasch analysis. Methods RUMM 2030 was used to analyse the mini-MAC data (n=851. Separate Rasch analyses were conducted for each of the original mini-MAC subscales as well as the over-arching adaptive and maladaptive coping subscales to examine summary and individual model fit statistics, person separation index (PSI, response format, local dependency, targeting, item bias (or differential item functioning -DIF, and dimensionality. Results For the fighting spirit, fatalism, and helplessness-hopelessness subscales, a revised three-point response format seemed more optimal than the original four-point response. To achieve model fit, items were deleted from four of the five subscales – Anxious Preoccupation items 7, 25, and 29; Cognitive Avoidance items 11 and 17; Fighting Spirit item 18; and Helplessness-Hopelessness items 16 and 20. For those subscales with sufficient items, analyses supported unidimensionality. Combining items to form the adaptive and maladaptive subscales was partially supported. Conclusions The original five subscales required item deletion and/or rescaling to improve goodness of fit to the Rasch model. While evidence was found for overarching subscales of

A measure of early physical functioning (EPF) post-stroke.

Science.gov (United States)

Finch, Lois E; Higgins, Johanne; Wood-Dauphinee, Sharon; Mayo, Nancy E

2008-07-01

To develop a comprehensive measure of Early Physical Functioning (EPF) post-stroke quantified through Rasch analysis and conceptualized using the International Classification of Functioning Disability and Health (ICF). An observational cohort study. A cohort of 262 subjects (mean age 71.6 (standard deviation 12.5) years) hospitalized post-acute stroke. Functional assessments were made within 3 days of stroke with items from valid and reliable indices commonly utilized to evaluate stroke survivors. Information on important variables was also collected. Principal component and Rasch analysis confirmed the factor structure, and dimensionality of the measure. Rasch analysis combined items across ICF components to develop the measure. Items were deleted iteratively, those retained fit the model and were related to the construct; reliability and validity were assessed. A 38-item unidimensional measure of the EPF met all Rasch model requirements. The item difficulty matched the person ability (mean person measure: -0.31; standard error 0.37 logits), reliability of the person-item-hierarchy was excellent at 0.97. Initial validity was adequate. The 38-item EPF measure was developed. It expands the range of assessment post acute stroke; it covers a broad spectrum of difficulty with good initial psychometric properties that, once revalidated, can assist in planning and evaluating early interventions.

The HGF Receptor c-Met Is Overexpressed in Esophageal Adenocarcinoma

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Luis J. Herrera

2005-01-01

Full Text Available The hepatocyte growth factor (HGF receptor, Met, has established oncogenic properties; however, its expression and function in esophageal adenocarcinoma (EA remain poorly understood. We aimed to determine the expression and potential alterations in Met expression in EA. Met expression was investigated in surgical specimens of EA, Barrett's esophagus (BE, and normal esophagus (NE using immunohistochemistry (IHC and quantitative reverse transcriptase polymerase chain reaction. Met expression, phosphorylation, and the effect of COX-2 inhibition on expression were examined in EA cell lines. IHC demonstrated intense Met immunoreactivity in all (100% EA and dysplastic BE specimens. In contrast, minimal immunostaining was observed in BE without dysplasia or NE specimens. Met mRNA and protein levels were increased in three EA cell lines, and Met protein was phosphorylated in the absence of serum. Sequence analysis found the kinase domain of c-met to be wild type in all three EA cell lines. HGF mRNA expression was identified in two EA cell lines. In COX-2-overexpressing cells, COX-2 inhibition decreased Met expression. Met is consistently overexpressed in EA surgical specimens and in three EA cell lines. Met dysregulation occurs early in Barrett's dysplasia to adenocarcinoma sequence. Future study of Met inhibition as a potential biologic therapy for EA is warranted.

Development of a Microsoft Excel tool for one-parameter Rasch model of continuous items: an application to a safety attitude survey

Directory of Open Access Journals (Sweden)

Tsair-Wei Chien

2017-01-01

Full Text Available Abstract Background Many continuous item responses (CIRs are encountered in healthcare settings, but no one uses item response theory’s (IRT probabilistic modeling to present graphical presentations for interpreting CIR results. A computer module that is programmed to deal with CIRs is required. To present a computer module, validate it, and verify its usefulness in dealing with CIR data, and then to apply the model to real healthcare data in order to show how the CIR that can be applied to healthcare settings with an example regarding a safety attitude survey. Methods Using Microsoft Excel VBA (Visual Basic for Applications, we designed a computer module that minimizes the residuals and calculates model’s expected scores according to person responses across items. Rasch models based on a Wright map and on KIDMAP were demonstrated to interpret results of the safety attitude survey. Results The author-made CIR module yielded OUTFIT mean square (MNSQ and person measures equivalent to those yielded by professional Rasch Winsteps software. The probabilistic modeling of the CIR module provides messages that are much more valuable to users and show the CIR advantage over classic test theory. Conclusions Because of advances in computer technology, healthcare users who are familiar to MS Excel can easily apply the study CIR module to deal with continuous variables to benefit comparisons of data with a logistic distribution and model fit statistics.

Nisine geholpen met hordentechnologie

NARCIS (Netherlands)

Jong, de L.S.

2001-01-01

Een combinatie van nisine met carvacrol, thymol of carvon leidde tot een synergistische reductie van het aantal levensvatbare cellen van Listeria monocytogenes en Bacillus cereus. Verslag van een promotieonderzoek

A comparison of metabolic syndrome (MetS) risk factors in Filipino women and Filipino American women: a pilot study.

Science.gov (United States)

Ancheta, Irma B; Battie, Cynthia A; Tuason, Teresa; Ancheta, Christine V

2012-01-01

Cardiovascular disease (CVD) is a significant cause of morbidity and mortality in women of Filipino ethnicity. The objective of our work was to determine if metabolic syndrome (MetS), a modifiable CVD risk factor, differs in women as a function of country of residency and to determine if, CVD prevention strategies need to differ for these groups of Filipino women. Data were collected in community-based health screenings for this cross-sectional study. PARTICIPANTS were recruited at places of worship in southeast United States (n=60) and Central Visayas, Philippines (n=56). Prevalence of MetS and its component factors as defined by the International Diabetes Federation criteria. The prevalence of MetS in Filipino women (FW) and Filipino American women (FAW) groups was similar (52% vs 55%, P=.08) although the prevalence of elevated waist circumference was greater for FAW (78% vs 59%, P=.03). Conversely, the percentage of FW women with risk-associated high-density lipoprotein (HDL) levels was higher than the FAW group (84% vs 42%, PFilipino women regardless of the country of residency although the FAW tended to have higher rates of central obesity while the FW tended to have higher rates of risk-associated HDL levels. Further research should examine the cause of these differences in order to develop better cardiovascular screening and intervention strategies.

Met1-linked Ubiquitination in Immune Signalling

DEFF Research Database (Denmark)

Fiil, Berthe Katrine; Gyrd-Hansen, Mads

2014-01-01

Methionine 1-linked ubiquitin chains (Met1-Ub), or linear ubiquitin, has emerged as a central post-translational modification in innate immune signalling. Molecular machinery that assembles, senses and, more recently, disassembles Met1-Ub has been identified, and technical advances have enabled...... identification of physiological substrates for Met1-Ub in response to activation of innate immune receptors. These discoveries have significantly advanced our understanding of how non-degradative ubiquitin modifications control pro-inflammatory responses mediated by nuclear factor κB and mitogen...

Factors Influencing Singapore Students' Choice of Physics as a Tertiary Field of Study: A Rasch analysis

Science.gov (United States)

Oon, Pey-Tee; Subramaniam, R.

2013-01-01

Asian students often perform well in international science and mathematics assessments. Their attitude toward technical subjects, such as physics, remains curious for many. The present study examines Singapore school students' views on various aspects of physics according to whether they intend to choose physics as an advanced field of study. A sample of 1076 physics students, from 16 secondary schools and junior colleges, participated in this study. The students were categorized as physics choosers or non-choosers according to their indicated intention, as sought in the survey, to study or not to study physics as a major subject at university after their leaving level examinations. Rasch-anchored analysis was employed to interpret the results; the use of Rasch analysis has helped to overcome significantly the psychometric limitations inherent in the treatment of Likert scale type of data using traditional analysis. As expected, the image of physics as a difficult subject surfaced in the samples used in our study. The students recognized unequivocally the utilitarian value of physics: physics is said to enhance career options and is necessary for technological progress to occur in a country. They also showed high interest in school physics-this is so even for students who are not keen to study physics in the future, a finding which is at variance with other studies reported from Western countries. School physics is seen to be relevant, and physics teachers are viewed as being able to foster students' interest in physics. Laboratory work, enrichment activities, and physics textbooks were reported to be important in order to encourage students to like physics. Though the physics choosers showed greater intention in physics, they were generally not inclined to pursue physics-related careers after graduation. Parents and peers at school, on the other hand, are perceived to display unenthusiastic attitudes toward physics. Possible reasons for these are discussed along

Predicting the need for institutional care shortly after admission to rehabilitation: Rasch analysis and predictive validity of the BRASS Index.

Science.gov (United States)

Panella, L; La Porta, F; Caselli, S; Marchisio, S; Tennant, A

2012-09-01

Effective discharge planning is increasingly recognised as a critical component of hospital-based Rehabilitation. The BRASS index is a risk screening tool for identification, shortly after hospital admission, of patients who are at risk of post-discharge problems. To evaluate the internal construct validity and reliability of the Blaylock Risk Assessment Screening Score (BRASS) within the rehabilitation setting. Observational prospective study. Rehabilitation ward of an Italian district hospital. One hundred and four consecutively admitted patients. Using classical psychometric methods and Rasch analysis (RA), the internal construct validity and reliability of the BRASS were examined. Also, external and predictive validity of the Rasch-modified BRASS (RMB) score were determined. Reliability of the original BRASS was low (Cronbach's alpha=0.595) and factor analyses showed that it was clearly multidimensional. A RA, based on a reduced 7-BRASS item set (RMB), satisfied model's expectations. Reliability was 0.777. The RMB scores strongly correlated with the original BRASS (rho=0.952; P28 days (RR=7.6, 95%CI=1.8-31.9). This study demonstrated that the original BRASS was multidimensional and unreliable. However, the RMB holds adequate internal construct validity and is sufficiently reliable as a predictor of discharge problems for group, but not individual use. The application of tools and methods (such as the BRASS Index) developed under the biomedical paradigm in a Physical and Rehabilitation Medicine setting may have limitations. Further research is needed to develop, within the rehabilitation setting, a valid measuring tool of risk of post-discharge problems at the individual level.

Psychometric properties of the Zarit Caregiver Burden Interview administered to caregivers to patients with Duchenne muscular dystrophy: a Rasch analysis.

Science.gov (United States)

Landfeldt, Erik; Mayhew, Anna; Straub, Volker; Bushby, Katharine; Lochmüller, Hanns; Lindgren, Peter

2017-12-18

To explore the psychometric properties of the full 22-item English (UK and US) version of the Zarit Caregiver Burden Interview administered to caregivers to patients with Duchenne muscular dystrophy. Caregivers to patients with Duchenne muscular dystrophy from the United Kingdom and the United States, recruited through the TREAT-NMD network, completed the Zarit Caregiver Burden Interview online. The psychometric properties of the Zarit Caregiver Burden Interview were examined using Rasch analysis. A total of 475 caregivers completed the Zarit Caregiver Burden Interview. Model misfit was identified for 9 of 22 items (mean item fit residual 0.061, SD: 2.736) and 13 of 22 items displayed disordered thresholds. The overall item-trait interaction chi-square value was 499 (198 degrees of freedom, p Interview fails to fully operationalize a quantitative conceptualization of caregiver burden among caregivers to patients with Duchenne muscular dystrophy from the United Kingdom and the United States. Further research is needed to understand the psychometric properties of the Zarit Caregiver Burden Interview in other populations and settings. Implications for Rehabilitation Duchenne muscular dystrophy is a terminal disease characterized by progressive muscle degeneration resulting in substantial disability and a significant burden on family caregivers. The Zarit Caregiver Burden Interview is one of the most widely applied measures of caregiver burden. Our Rasch analysis suggests that the Zarit Caregiver Burden Interview is not fit for purpose to measure burden in UK and US caregivers to patients with Duchenne muscular dystrophy. Clinicians and decision-makers should interpret Zarit Caregiver Burden Interview data from these populations with caution.

Effects of the BDNF Val66Met polymorphism and met allele load on declarative memory related neural networks

DEFF Research Database (Denmark)

Dodds, Chris M; Henson, Richard N; Suckling, John

2013-01-01

It has been suggested that the BDNF Val66Met polymorphism modulates episodic memory performance via effects on hippocampal neural circuitry. However, fMRI studies have yielded inconsistent results in this respect. Moreover, very few studies have examined the effect of met allele load on activatio...

Hydrogen storage capacity of titanium met-cars

International Nuclear Information System (INIS)

Akman, N; Durgun, E; Yildirim, T; Ciraci, S

2006-01-01

The adsorption of hydrogen molecules on the titanium metallocarbohedryne (met-car) cluster has been investigated by using the first-principles plane wave method. We have found that, while a single Ti atom at the corner can bind up to three hydrogen molecules, a single Ti atom on the surface of the cluster can bind only one hydrogen molecule. Accordingly, a Ti 8 C 12 met-car can bind up to 16 H 2 molecules and hence can be considered as a high-capacity hydrogen storage medium. Strong interaction between two met-car clusters leading to the dimer formation can affect H 2 storage capacity slightly. Increasing the storage capacity by directly inserting H 2 into the met-car or by functionalizing it with an Na atom have been explored. It is found that the insertion of neither an H 2 molecule nor an Na atom could further promote the H 2 storage capacity of a Ti 8 C 12 cluster. We have also tested the stability of the H 2 -adsorbed Ti 8 C 12 met-car with ab initio molecular dynamics calculations which have been carried out at room temperature

The Cervical Dystonia Impact Profile (CDIP-58: Can a Rasch developed patient reported outcome measure satisfy traditional psychometric criteria?

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Bhatia Kailash P

2008-08-01

Full Text Available Abstract Background The United States Food and Drug Administration (FDA are currently producing guidelines for the scientific adequacy of patient reported outcome measures (PROMs in clinical trials, which will have implications for the selection of scales used in future clinical trials. In this study, we examine how the Cervical Dystonia Impact Profile (CDIP-58, a rigorous Rasch measurement developed neurologic PROM, stands up to traditional psychometric criteria for three reasons: 1 provide traditional psychometric evidence for the CDIP-58 in line with proposed FDA guidelines; 2 enable researchers and clinicians to compare it with existing dystonia PROMs; and 3 help researchers and clinicians bridge the knowledge gap between old and new methods of reliability and validity testing. Methods We evaluated traditional psychometric properties of data quality, scaling assumptions, targeting, reliability and validity in a group of 391 people with CD. The main outcome measures used were the CDIP-58, Medical Outcome Study Short Form-36, the 28-item General Health Questionnaire, and Hospital and Anxiety and Depression Scale. Results A total of 391 people returned completed questionnaires (corrected response rate 87%. Analyses showed: 1 data quality was high (low missing data ≤ 4%, subscale scores could be computed for > 96% of the sample; 2 item groupings passed tests for scaling assumptions; 3 good targeting (except for the Sleep subscale, ceiling effect = 27%; 4 good reliability (Cronbach's alpha ≥ 0.92, test-retest intraclass correlations ≥ 0.83; and 5 validity was supported. Conclusion This study has shown that new psychometric methods can produce a PROM that stands up to traditional criteria and supports the clinical advantages of Rasch analysis.

An introduction to Item Response Theory and Rasch Analysis of the Eating Assessment Tool (EAT-10).

Science.gov (United States)

Kean, Jacob; Brodke, Darrel S; Biber, Joshua; Gross, Paul

2018-03-01

Item response theory has its origins in educational measurement and is now commonly applied in health-related measurement of latent traits, such as function and symptoms. This application is due in large part to gains in the precision of measurement attributable to item response theory and corresponding decreases in response burden, study costs, and study duration. The purpose of this paper is twofold: introduce basic concepts of item response theory and demonstrate this analytic approach in a worked example, a Rasch model (1PL) analysis of the Eating Assessment Tool (EAT-10), a commonly used measure for oropharyngeal dysphagia. The results of the analysis were largely concordant with previous studies of the EAT-10 and illustrate for brain impairment clinicians and researchers how IRT analysis can yield greater precision of measurement.

Is neurofeedback effectief bij kinderen met ADHD?

NARCIS (Netherlands)

de Hen, M.H.; Geurts, H.M.

2008-01-01

Kan neurofeedback verantwoord ingezet worden bij de behandeling van kinderen met ADHD? Omdeze vraag te beantwoorden worden zeven recente onderzoeken naar de effectiviteit van neurofeedback bij kinderen met ADHD geanalyseerd. Ondanks dat de resultaten in eerste instantie lijken te suggereren dat

Proef met duurzaam watergebruik in de bollenstreek

NARCIS (Netherlands)

Fliegenthart, F.; Dik, P.E.; Groenendijk, P.

2009-01-01

In 2007 begon in de Wieringermeer een praktijkproef met alternatieve waterbeheersystemen voor de bollenteelt. Met drie verschillende teeltsystemen wordt onderzoek verricht naar zo optimaal mogelijk gebruik van zoet water door recirculatie en hergebruik. Ook loopt onderzoek naar de emissie van

Mars MetNet Mission Pressure and Humidity Devices

Science.gov (United States)

Haukka, H.; Harri, A.-M.; Schmidt, W.; Genzer, M.; Polkko, J.; Kemppinen, O.; Leinonen, J.

2012-09-01

A new kind of planetary exploration mission for Mars is being developed in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission [1] is based on a new semi-hard landing vehicle called MetNet Lander (MNL). MetBaro and MetHumi are part of the scientific payload of the MNL. Main scientific goal of both devices is to measure the meteorological phenomena (pressure and humidity) of the Martian atmosphere and complement the previous Mars mission atmospheric measurements (Viking and Phoenix) for better understanding of the Martian atmospheric conditions.

Aptamers Binding to c-Met Inhibiting Tumor Cell Migration.

Directory of Open Access Journals (Sweden)

Birgit Piater

Full Text Available The human receptor tyrosine kinase c-Met plays an important role in the control of critical cellular processes. Since c-Met is frequently over expressed or deregulated in human malignancies, blocking its activation is of special interest for therapy. In normal conditions, the c-Met receptor is activated by its bivalent ligand hepatocyte growth factor (HGF. Also bivalent antibodies can activate the receptor by cross linking, limiting therapeutic applications. We report the generation of the RNA aptamer CLN64 containing 2'-fluoro pyrimidine modifications by systematic evolution of ligands by exponential enrichment (SELEX. CLN64 and a previously described single-stranded DNA (ssDNA aptamer CLN3 exhibited high specificities and affinities to recombinant and cellular expressed c-Met. Both aptamers effectively inhibited HGF-dependent c-Met activation, signaling and cell migration. We showed that these aptamers did not induce c-Met activation, revealing an advantage over bivalent therapeutic molecules. Both aptamers were shown to bind overlapping epitopes but only CLN3 competed with HGF binding to cMet. In addition to their therapeutic and diagnostic potential, CLN3 and CLN64 aptamers exhibit valuable tools to further understand the structural and functional basis for c-Met activation or inhibition by synthetic ligands and their interplay with HGF binding.

A first-in-human phase I study of SAR125844, a selective MET tyrosine kinase inhibitor, in patients with advanced solid tumours with MET amplification.

Science.gov (United States)

Angevin, Eric; Spitaleri, Gianluca; Rodon, Jordi; Dotti, Katia; Isambert, Nicolas; Salvagni, Stefania; Moreno, Victor; Assadourian, Sylvie; Gomez, Corinne; Harnois, Marzia; Hollebecque, Antoine; Azaro, Analia; Hervieu, Alice; Rihawi, Karim; De Marinis, Filippo

2017-12-01

Dysregulated MET signalling is implicated in oncogenesis. The safety and preliminary efficacy of a highly selective MET kinase inhibitor (SAR125844) was investigated in patients with advanced solid tumours and MET dysregulation. This was a phase I dose-escalation (3 + 3 design [50-740 mg/m 2 ]) and dose-expansion study. In the dose escalation, patients had high total MET (t-MET) expression by immunohistochemistry (IHC) or MET amplification by fluorescence in situ hybridisation. In the dose expansion, patients had MET amplification (including a subset of patients with non-small cell lung cancer [NSCLC]) or phosphorylated-MET (p-MET) expression (IHC). Objectives were determination of maximum tolerated dose (MTD) of once-weekly intravenous SAR125844 based on dose-limiting toxicities; safety and pharmacokinetic profile; preliminary efficacy of SAR125844 MTD in the expansion cohort. In total, 72 patients were enrolled: dose escalation, N = 33; dose expansion, N = 39; 570 mg/m 2 was established as the MTD. Most frequent treatment-emergent adverse events (AEs) were asthenia/fatigue (58.3%), nausea (31.9%), and abdominal pain, constipation, and dyspnea (27.8% for each); 58.3% of patients reported grade 3 AEs (19.4% were treatment related). Of the 29 evaluable patients with MET amplification treated at 570 mg/m 2 , five achieved a partial response, including four of 22 with NSCLC; 17 patients had stable disease. No response was observed in patients with high p-MET solid tumours. There was no correlation between tumour response and t-MET status or MET gene copy number. The MTD of once-weekly SAR125844 was 570 mg/m 2 ; SAR125844 was well tolerated, with significant antitumour activity in patients with MET-amplified NSCLC. NCT01391533. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Internal construct validity of the Warwick-Edinburgh Mental Well-being Scale (WEMWBS: a Rasch analysis using data from the Scottish Health Education Population Survey

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Platt Stephen

2009-02-01

Full Text Available Abstract Background The Warwick-Edinburgh Mental Well-Being Scale (WEMWBS was developed to meet demand for instruments to measure mental well-being. It comprises 14 positively phrased Likert-style items and fulfils classic criteria for scale development. We report here the internal construct validity of WEMWBS from the perspective of the Rasch measurement model. Methods The model was applied to data collected from 779 respondents in Wave 12 (Autumn 2006 of the Scottish Health Education Population Survey. Respondents were aged 16–74 (average 41.9 yrs. Results Initial fit to model expectations was poor. The items 'I've been feeling good about myself', 'I've been interested in new things' and 'I've been feeling cheerful' all showed significant misfit to model expectations, and were deleted. This led to a marginal improvement in fit to the model. After further analysis, more items were deleted and a strict unidimensional seven item scale (the Short Warwick Edinburgh Mental Well-Being Scale (SWEMWBS was resolved. Many items deleted because of misfit with model expectations showed considerable bias for gender. Two retained items also demonstrated bias for gender but, at the scale level, cancelled out. One further retained item 'I've been feeling optimistic about the future' showed bias for age. The correlation between the 14 item and 7 item versions was 0.954. Given fit to the Rasch model, and strict unidimensionality, SWEMWBS provides an interval scale estimate of mental well-being. Conclusion A short 7 item version of WEMWBS was found to satisfy the strict unidimensionality expectations of the Rasch model, and be largely free of bias. This scale, SWEMWBS, provides a raw score-interval scale transformation for use in parametric procedures. In terms of face validity, SWEMWBS presents a more restricted view of mental well-being than the 14 item WEMWBS, with most items representing aspects of psychological and eudemonic well-being, and few covering

Effective implementation of novel MET pharmacodynamic assays in translational studies.

Science.gov (United States)

Srivastava, Apurva K; Navas, Tony; Herrick, William G; Hollingshead, Melinda G; Bottaro, Donald P; Doroshow, James H; Parchment, Ralph E

2017-01-01

MET tyrosine kinase (TK) dysregulation is significantly implicated in many types of cancer. Despite over 20 years of drug development to target MET in cancers, a pure anti-MET therapeutic has not yet received market approval. The failure of two recently concluded phase III trials point to a major weakness in biomarker strategies to identify patients who will benefit most from MET therapies. The capability to interrogate oncogenic mutations in MET via circulating tumor DNA (ctDNA) provides an important advancement in identification and stratification of patients for MET therapy. However, a wide range in type and frequency of these mutations suggest there is a need to carefully link these mutations to MET dysregulation, at least in proof-of-concept studies. In this review, we elaborate how we can utilize recently developed and validated pharmacodynamic biomarkers of MET not only to show target engagement, but more importantly to quantitatively measure MET dysregulation in tumor tissues. The MET assay endpoints provide evidence of both canonical and non-canonical MET signaling, can be used as "effect markers" to define biologically effective doses (BEDs) for molecularly targeted drugs, confirm mechanism-of-action in testing combination of drugs, and establish whether a diagnostic test is reporting MET dysregulation. We have established standard operating procedures for tumor biopsy collections to control pre-analytical variables that have produced valid results in proof-of-concept studies. The reagents and procedures are made available to the research community for potential implementation on multiple platforms such as ELISA, quantitative immunofluorescence assay (qIFA), and immuno-MRM assays.

Comparative study of middle school students' attitudes towards science: Rasch analysis of entire TIMSS 2011 attitudinal data for England, Singapore and the U.S.A. as well as psychometric properties of attitudes scale

Science.gov (United States)

Pey Tee, Oon; Subramaniam, R.

2018-02-01

We report here on a comparative study of middle school students' attitudes towards science involving three countries: England, Singapore and the U.S.A. Complete attitudinal data sets from TIMSS (Trends in International Mathematics and Science Study) 2011 were used, thus giving a very large sample size (N = 20,246), compared to other studies in the journal literature. The Rasch model was used to analyse the data, and the findings have shed some useful light on not only how the Western and Asian students responded on a comparative basis in the various scales related to attitudes but also on the validity, reliability, and unidimensionality of the attitudes instrument used in TIMSS 2011. There may be a need for TIMSS test developers to consider doing away with negatively phrased items in the attitudes instrument and phrasing these positively as the Rasch framework shows that response bias is associated with these statements.

Measurement properties of the CLOX Executive Clock Drawing Task in an inpatient stroke rehabilitation setting.

Science.gov (United States)

Zuverza-Chavarria, Virginia; Tsanadis, John

2011-05-01

The goal of this study was to explore the psychometric properties of the CLOX Executive Clock Drawing Task (Royall, Cordes, & Polk, 1998) in persons who had sustained a stroke and were receiving inpatient rehabilitation. Rasch modeling was utilized to examine the psychometric properties of the CLOX. Separate analyses were conducted for the free draw (CLOX 1) and copy (CLOX 2) portions of the measure to investigate each presentation mode independently. The sample consisted of 66 inpatient adults who had sustained a stroke. CLOX 1 met most Rasch model expectations for item fit, unidimensionality, test reliability, and sample targeting. CLOX 2 was less psychometrically sound and contained two items with significant misfit. CLOX 2 demonstrated a significant ceiling effect that resulted in poor sample targeting. CLOX 1 is a psychometrically sound screening instrument for assessing persons with stroke receiving inpatient rehabilitation. In addition to the psychometric weaknesses of CLOX 2, its interpretive yield is minimal and clinicians may consider omitting it. Recommendations are made for using the Rasch item-person maps in clinical practice.

When Historiography Met Epistemology

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Jean-François Stoffel

2017-06-01

Full Text Available Review of Bordoni, Stefano. When historiography met epistemology: Sophisticated histories and philosophies of science in French-speaking countries in the second half of the nineteenth century. Reviewed by Jean-François Stoffel.

Ribosome•RelA structures reveal the mechanism of stringent response activation

Science.gov (United States)

Loveland, Anna B; Bah, Eugene; Madireddy, Rohini; Zhang, Ying; Brilot, Axel F; Grigorieff, Nikolaus; Korostelev, Andrei A

2016-01-01

Stringent response is a conserved bacterial stress response underlying virulence and antibiotic resistance. RelA/SpoT-homolog proteins synthesize transcriptional modulators (p)ppGpp, allowing bacteria to adapt to stress. RelA is activated during amino-acid starvation, when cognate deacyl-tRNA binds to the ribosomal A (aminoacyl-tRNA) site. We report four cryo-EM structures of E. coli RelA bound to the 70S ribosome, in the absence and presence of deacyl-tRNA accommodating in the 30S A site. The boomerang-shaped RelA with a wingspan of more than 100 Å wraps around the A/R (30S A-site/RelA-bound) tRNA. The CCA end of the A/R tRNA pins the central TGS domain against the 30S subunit, presenting the (p)ppGpp-synthetase domain near the 30S spur. The ribosome and A/R tRNA are captured in three conformations, revealing hitherto elusive states of tRNA engagement with the ribosomal decoding center. Decoding-center rearrangements are coupled with the step-wise 30S-subunit 'closure', providing insights into the dynamics of high-fidelity tRNA decoding. DOI: http://dx.doi.org/10.7554/eLife.17029.001 PMID:27434674

Saving energy with paint. Coating with ceramic globules; Energie besparen met verf. Coating met keramische bolletjes

Energy Technology Data Exchange (ETDEWEB)

Willemse, R. [Coateq Coatings, Haarlem (Netherlands)

2011-07-01

The special paint coating of ThermoShield saves energy. The coating consists for 50% of hollow, vacuum ceramic globules. The waterborne damp-open coating with capillary function resists rain water and removes redundant water in case of draught and it reflects sunlight. [Dutch] Met de speciale verfcoating ThermoShield kan energie worden bespaard. De coating bestaat voor 50% uit holle, vacuum getrokken keramische bolletjes. De watergedragen damp-open coating met capillaire werking stoot bij regen water af en voert bij droogte overtollig vocht af en reflecteert zonlicht.

Groen proceswater: zuivering brouwerijprocesafvalwater met microalgen : Resultaten onderzoek 2013

NARCIS (Netherlands)

Dijk, van W.; Diem, van A.; Doornbusch, P.; Grobben-Gaastra, S.A.; Kleinhout, G.; Kroon, A.; Weide, van der R.Y.

2014-01-01

Afgelopen jaar is de pilot met het kweken van algen met afvalwater van de brouwerijlocatie Zoeterwoude geslaagd. Dit is gedaan in een samenwerkingsverband van Heineken Nederland BV, Algae Food & Fuel en WUR-Acrres. Dit is de eerste inline pilot in de wereld waarbij met LED verlichting op 1000 L

Uso del modelo de Rasch para poner en la misma escala las puntuaciones de distintos tests

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Gerardo Prieto-Adánez

2003-01-01

Full Text Available Los usuarios de los tests tienen que poner en una escala común las puntuaciones de distintos instrumentos en varias situaciones prácticas, tales como la evaluación académica, la selección de personal, los estudios acerca del cambio de un atributo psicológico o educativo, la construcción de bancos de ítems, la validación intercultural de tests y los estudios sobre el funcionamiento diferencial de los ítems. Situar en una escala común las puntuaciones de diferentes tests es una de las principales aplicaciones del modelo de Rasch. En este artículo, mostramos el proceso de equiparación de dos tests (diseño, análisis de datos e interpretación usando como anclaje un conjunto de ítems comunes.

Validation of the malaysian versions of parents and children health survey for asthma by using rasch-model.

Science.gov (United States)

Hussein, Maryam Se; Akram, Waqas; Mamat, Mohd Nor; Majeed, Abu Bakar Abdul; Ismail, Nahlah Elkudssiah Binti

2015-04-01

In recent years, health-related quality of life (HRQOL) has become an important outcome measure in epidemiologic studies and clinical trials. For patients with asthma there are many instruments but most of them have been developed in English. With the increase in research project, researchers working in other languages have two options; either to develop a new measure or to translate an already developed measure. Children Health Survey for Asthma is developed by American Academy of Paediatrics which has two versions one for the parents (CHSA) and the other for the child (CHSA-C). However, there is no Malay version of the CHSA or the CHSA-C. The aim of this study was to translate and determine the validity and reliability of the Malaysian versions of Parent and Children Health Survey for Asthma. Questionnaires were translated to Bahasa Malayu using previously established guidelines, data from 180 respondents (asthmatic children and their parent) were analysed using Rasch-Model; as, it is an approach that has been increasingly used in health field and also it explores the performance of each item rather than total set score. The internal consistency was high for the parent questionnaire (CHSA) (reliability score for persons = 0.88 and for items was 0.97), and good for child questionnaire (CHSA-C) (reliability score for persons = 0.83 and for items was 0.94). Also, this study shows that all items measure for both questionnaires (CHSA and CHSA-C) are fitted to Rasch-Model. This study produced questionnaires that are conceptually equivalent to the original, easy to understand for the children and their parents, and good in terms of internal consistency. Because of the questionnaire has two versions one for the child and the other for the parents, they could be used in clinical practice to measure the effect of asthma on the child and their families. This current research had translated two instruments to other language (BahasaMalayu) and evaluated their reliability and

Efficacy of c-Met inhibitor for advanced prostate cancer

International Nuclear Information System (INIS)

Tu, William H; Zhu, Chunfang; Clark, Curtis; Christensen, James G; Sun, Zijie

2010-01-01

Aberrant expression of HGF/SF and its receptor, c-Met, often correlates with advanced prostate cancer. Our previous study showed that expression of c-Met in prostate cancer cells was increased after attenuation of androgen receptor (AR) signalling. This suggested that current androgen ablation therapy for prostate cancer activates c-Met expression and may contribute to development of more aggressive, castration resistant prostate cancer (CRPC). Therefore, we directly assessed the efficacy of c-Met inhibition during androgen ablation on the growth and progression of prostate cancer. We tested two c-Met small molecule inhibitors, PHA-665752 and PF-2341066, for anti-proliferative activity by MTS assay and cell proliferation assay on human prostate cancer cell lines with different levels of androgen sensitivity. We also used renal subcapsular and castrated orthotopic xenograft mouse models to assess the effect of the inhibitors on prostate tumor formation and progression. We demonstrated a dose-dependent inhibitory effect of PHA-665752 and PF-2341066 on the proliferation of human prostate cancer cells and the phosphorylation of c-Met. The effect on cell proliferation was stronger in androgen insensitive cells. The c-Met inhibitor, PF-2341066, significantly reduced growth of prostate tumor cells in the renal subcapsular mouse model and the castrated orthotopic mouse model. The effect on cell proliferation was greater following castration. The c-Met inhibitors demonstrated anti-proliferative efficacy when combined with androgen ablation therapy for advanced prostate cancer

A protective effect of the BDNF Met/Met genotype in obesity in healthy Caucasian subjects but not in patients with coronary heart disease.

Science.gov (United States)

Sustar, A; Nikolac Perkovic, M; Nedic Erjavec, G; Svob Strac, D; Pivac, N

2016-08-01

Brain-derived neurotrophic factor (BDNF) is a neurotrophic factor with an important role in the regulation of body weight, body mass index (BMI) and obesity. Increased BMI that leads to obesity is a substantial risk factor for coronary heart disease (CHD). The functional BDNF Val66Met polymorphism (rs6265) has been associated with CHD, obesity and BMI. The aim of the study was to determine the association between BDNF rs6265 polymorphism and CHD and/or BMI in patients with CHD and healthy control subjects. The study included 704 Caucasian subjects: 206 subjects with CHD and 498 healthy control subjects. The BDNF rs6265 genotype frequency was similar in male and female subjects, and there were no differences in the frequency of the BDNF rs6265 genotypes in 206 patients with CHD and in 498 healthy subjects. When study participants were subdivided according to the BMI categories into normal weight, overweight and obese subjects, significantly different BDNF rs6265 genotype frequency was found within healthy subjects, but not within patients with CHD. Healthy subjects, but not patients with CHD, subdivided into carriers of the Met/Met, Met/Val and Val/Val genotype, had different BMI scores. The BDNF rs6265 genotype frequency was similar in male and female subjects, and there were no differences in the frequency of the BDNF rs6265 genotypes in 206 patients with CHD and in 498 healthy subjects. When study participants were subdivided according to the BMI categories into normal weight, overweight and obese subjects, significantly different BDNF rs6265 genotype frequency was found within healthy subjects, but not within patients with CHD. Healthy subjects, but not patients with CHD, subdivided into carriers of the Met/Met, Met/Val and Val/Val genotype, had different BMI scores. BDNF rs6265 polymorphism was not associated with a diagnosis of CHD or with BMI categories among patients with CHD. In contrast, healthy Caucasians, carriers of the BDNF Met/Met genotype, had more

Mars MetNet Mission - Martian Atmospheric Observational Post Network

Science.gov (United States)

Hari, Ari-Matti; Haukka, Harri; Aleksashkin, Sergey; Arruego, Ignacio; Schmidt, Walter; Genzer, Maria; Vazquez, Luis; Siikonen, Timo; Palin, Matti

2017-04-01

A new kind of planetary exploration mission for Mars is under development in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semi-hard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested. 1. MetNet Lander The MetNet landing vehicles are using an inflatable entry and descent system instead of rigid heat shields and parachutes as earlier semi-hard landing devices have used. This way the ratio of the payload mass to the overall mass is optimized. The landing impact will burrow the payload container into the Martian soil providing a more favorable thermal environment for the electronics and a suitable orientation of the telescopic boom with external sensors and the radio link antenna. It is planned to deploy several tens of MNLs on the Martian surface operating at least partly at the same time to allow meteorological network science. 2. Strawman Scientific Payload The strawman payload of the two MNL precursor models includes the following instruments: Atmospheric instruments: - MetBaro Pressure device - MetHumi Humidity device - MetTemp Temperature sensors Optical devices: - PanCam Panoramic - MetSIS Solar irradiance sensor with OWLS optical wireless system for data transfer - DS Dust sensor Composition and Structure Devices: Tri-axial magnetometer MOURA Tri-axial System Accelerometer The descent processes dynamic properties are monitored by a special 3-axis

Towards the development of clinical measures for spinal cord injury based on the International Classification of Functioning, Disability and Health with Rasch analyses.

Science.gov (United States)

Ballert, Carolina S; Stucki, Gerold; Biering-Sørensen, Fin; Cieza, Alarcos

2014-09-01

To determine whether the International Classification of Functioning, Disability and Health (ICF) categories relevant to spinal cord injury (SCI) can be integrated in clinical measures and to obtain insights to guide their future operationalization. Specific aims are to find out whether the ICF categories relevant to SCI fit a Rasch model taking into consideration the dimensionality found in previous investigations, local item dependencies, or differential item functioning. All second-level ICF categories collected in the Development of ICF Core Sets for SCI project in specialized centers within 15 countries from 2006 through 2008. Secondary data analysis. Adults (N=1048) with SCI from the early postacute and long-term living context. Not applicable. Two unidimensional Rasch analyses: one for the ICF categories from body functions and body structures components and another for the ICF categories from the activities and participation component. Results support good reliability and targeting of the ICF categories in both dimensions. In each dimension, few ICF categories were subject to misfit. Local item dependency was observed between ICF categories of the same chapters. Group effects for age and sex were observed only to a small extent. The validity of ICF categories to develop measures of functioning in SCI for clinical practice and research is to some extent supported. Model adjustments were suggested to further improve their operationalization and psychometrics. Copyright © 2014 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Studeren met Hans Rosenberg

NARCIS (Netherlands)

Rutten, R.J.

2001-01-01

Hoe was het om in de jaren zestig te studeren? Laat ik een terugblik ophangen aan een studiemakker, Hans Rosenberg. We vormden samen de sterrekundejaar- gang 1961. Hans studeerde af in 1966 met hoofdvak wiskunde, promoveerde op radiostralingsprocessen in de zonnecorona in 1973, verliet de

Higher Levels of c-Met Expression and Phosphorylation Identify Cell Lines With Increased Sensitivity to AMG-458, a Novel Selective c-Met Inhibitor With Radiosensitizing Effects

International Nuclear Information System (INIS)

Li Bo; Torossian, Artour; Sun, Yunguang; Du, Ruihong; Dicker, Adam P.; Lu Bo

2012-01-01

Purpose: c-Met is overexpressed in some non-small cell lung cancer (NSCLC) cell lines and tissues. Cell lines with higher levels of c-Met expression and phosphorylation depend on this receptor for survival. We studied the effects of AMG-458 on 2 NSCLC cell lines. Methods and Materials: 3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl) -2H-tetrazolium assays assessed the sensitivities of the cells to AMG-458. Clonogenic survival assays illustrated the radiosensitizing effects of AMG-458. Western blot for cleaved caspase 3 measured apoptosis. Immunoblotting for c-Met, phospho-Met (p-Met), Akt/p-Akt, and Erk/p-Erk was performed to observe downstream signaling. Results: AMG-458 enhanced radiosensitivity in H441 but not in A549. H441 showed constitutive phosphorylation of c-Met. A549 expressed low levels of c-Met, which were phosphorylated only in the presence of exogenous hepatocyte growth factor. The combination of radiation therapy and AMG-458 treatment was found to synergistically increase apoptosis in the H441 cell line but not in A549. Radiation therapy, AMG-458, and combination treatment were found to reduce p-Akt and p-Erk levels in H441 but not in A549. H441 became less sensitive to AMG-458 after small interfering RNA knockdown of c-Met; there was no change in A549. After overexpression of c-Met, A549 became more sensitive, while H441 became less sensitive to AMG-458. Conclusions: AMG-458 was more effective in cells that expressed higher levels of c-Met/p-Met, suggesting that higher levels of c-Met and p-Met in NSCLC tissue may classify a subset of tumors that are more sensitive to molecular therapies against this receptor.

Klimaatverandering en de stadsboom (interview met Jitze Kopinga)

NARCIS (Netherlands)

Bennink, P.; Kopinga, J.

2010-01-01

Bomen in de stad staan vaak op warme plaatsen met een gebrekkige waterhuishouding. Volgens het KNMI zal Nederland in de toekomst steeds vaker met hitte en droogte te maken hebben. Wat betekent dat voor onze stadsbomen?

Rasch measurement of self-regulated learning in an information and communication technology (ICT)-rich environment.

Science.gov (United States)

Njiru, Joseph N; Waugh, Russell F

2007-01-01

This report describes how a linear scale of self-regulated learning in an ICT-rich environment was created by analysing student data using the Rasch measurement model. A person convenience sample of (N = 409) university students in Western Australia was used. The stem-item sample was initially 41, answered in two perspectives ("I aim for this" and "I actually do this"), and reduced to 16 that fitted the measurement model to form a unidimensional scale. Items for motivation (extrinsic rewards, intrinsic rewards, and social rewards), academic goals (fear of performing poorly) (but not standards), self-learning beliefs (ability and interest), task management (strategies and time management) (but not cooperative learning), Volition (action control (but not environmental control), and self-evaluation (cognitive self-evaluation and metacognition) fitted the measurement model. The proportion of observed variance considered true was 0.90. A new instrument is proposed to handle the conceptually valid but non-fitting items. Characteristics of high self-regulated learners are measured.

MetNet Network Mission for Martian Atmospheric Investigations

Science.gov (United States)

Harri, A.-M.; Alexashkin, S.; Arrugeo, I.; Schmidt, W.; Vazquez, L.; Genzer, M.; Haukka, H.

2014-07-01

A new kind of planetary exploration mission for Mars called MetNet is being developed for martian atmospheric investigations. The eventual scope of the MetNet Mission is to deploy tens of small landers on the martian surface.

Requirements to be met by the operation manual

International Nuclear Information System (INIS)

1981-03-01

The rule applies to the contents and the lay-out of the operating manual for stationary nuclear power plants. The draft contains: 1. General requirement to be met by the contents of the operating manual. The operating manual to be arranged in 4 parts (part 1: internal rules and regulations; part 2: operation overall plant; part 3: incidents; part 4: operation systems). Safety specifications to be included in the manual, the exemption being the system of technical documentation. 2. General requirements to be met by the lay-out of the operating manual. Comprehensibility; legibility; structure and subdivisions; arrangement of the instructions and design of the manuals cover. 3. Requirements to be met by part 1. Defining the various internal rules and regulations (personnel management); rules and regulations concerning inspections and shift work; maintenance and repair; radiation protection; guard duty and admission; alarm; fire protection; first aid. 4. Requirements to be met by part 2. Provisions and operational limitations; limit values important from the point of view of safety; normal operation; anomalous operation; in-service inspections. 6. Requirements to be met by part 3. 7. Annex: Rules, regulations and stipulations mentioned in the rule draft. (orig.)

Dimensionering van de Uniqfill chemischer wasser met lamellen

NARCIS (Netherlands)

Starmans, D.A.J.

2006-01-01

In dit rapport wordt een eerste aanzet gegeven tot de modellering van een kruisstroom chemische wasser met lamellen. Met behulp van bestaande metingen is de stofoverdrachtscoëfficiënt afgeschat, waarna scenario's voor nieuwe wassers doorgerekend konden worden.

Insulated hsp70B' promoter: stringent heat-inducible activity in replication-deficient, but not replication-competent adenoviruses.

Science.gov (United States)

Rohmer, Stanimira; Mainka, Astrid; Knippertz, Ilka; Hesse, Andrea; Nettelbeck, Dirk M

2008-04-01

Key to the realization of gene therapy is the development of efficient and targeted gene transfer vectors. Therapeutic gene transfer by replication-deficient or more recently by conditionally replication-competent/oncolytic adenoviruses has shown much promise. For specific applications, however, it will be advantageous to provide vectors that allow for external control of gene expression. The efficient cellular heat shock system in combination with available technology for focused and controlled hyperthermia suggests heat-regulated transcription control as a promising tool for this purpose. We investigated the feasibility of a short fragment of the human hsp70B' promoter, with and without upstream insulator elements, for the regulation of transgene expression by replication-deficient or oncolytic adenoviruses. Two novel adenoviral vectors with an insulated hsp70B' promoter were developed and showed stringent heat-inducible gene expression with induction ratios up to 8000-fold. In contrast, regulation of gene expression from the hsp70B' promoter without insulation was suboptimal. In replication-competent/oncolytic adenoviruses regulation of the hsp70B' promoter was lost specifically during late replication in permissive cells and could not be restored by the insulators. We developed novel adenovirus gene transfer vectors that feature improved and stringent regulation of transgene expression from the hsp70B' promoter using promoter insulation. These vectors have potential for gene therapy applications that benefit from external modulation of therapeutic gene expression or for combination therapy with hyperthermia. Furthermore, our study reveals that vector replication can deregulate inserted cellular promoters, an observation which is of relevance for the development of replication-competent/oncolytic gene transfer vectors. (c) 2008 John Wiley & Sons, Ltd.

Problems with the factor analysis of items: Solutions based on item response theory and item parcelling

Directory of Open Access Journals (Sweden)

Gideon P. De Bruin

2004-10-01

Full Text Available The factor analysis of items often produces spurious results in the sense that unidimensional scales appear multidimensional. This may be ascribed to failure in meeting the assumptions of linearity and normality on which factor analysis is based. Item response theory is explicitly designed for the modelling of the non-linear relations between ordinal variables and provides a strong alternative to the factor analysis of items. Items may also be combined in parcels that are more likely to satisfy the assumptions of factor analysis than do the items. The use of the Rasch rating scale model and the factor analysis of parcels is illustrated with data obtained with the Locus of Control Inventory. The results of these analyses are compared with the results obtained through the factor analysis of items. It is shown that the Rasch rating scale model and the factoring of parcels produce superior results to the factor analysis of items. Recommendations for the analysis of scales are made. Opsomming Die faktorontleding van items lewer dikwels misleidende resultate op, veral in die opsig dat eendimensionele skale as meerdimensioneel voorkom. Hierdie resultate kan dikwels daaraan toegeskryf word dat daar nie aan die aannames van lineariteit en normaliteit waarop faktorontleding berus, voldoen word nie. Itemresponsteorie, wat eksplisiet vir die modellering van die nie-liniêre verbande tussen ordinale items ontwerp is, bied ’n aantreklike alternatief vir die faktorontleding van items. Items kan ook in pakkies gegroepeer word wat meer waarskynlik aan die aannames van faktorontleding voldoen as individuele items. Die gebruik van die Rasch beoordelingskaalmodel en die faktorontleding van pakkies word aan die hand van data wat met die Lokus van Beheervraelys verkry is, gedemonstreer. Die resultate van hierdie ontledings word vergelyk met die resultate wat deur ‘n faktorontleding van die individuele items verkry is. Die resultate dui daarop dat die Rasch

MET overexpression, gene amplification and relevant clinicopathological features in gastric adenocarcinoma.

Science.gov (United States)

Zhang, Jing; Guo, Lei; Liu, Xiuyun; Li, Wenbin; Ying, Jianming

2017-02-07

This study was conducted to investigate the expression of MET in Chinese gastric adenocarcinoma cohort, the correlation between MET overexpression and clinical pathological features, HER2 expression and MET gene amplification. A total of 816 gastric adenocarcinoma patients were included and MET and HER2 immunohistochemical (IHC) staining were performed. IHC and dual-color silver in situ hybridization analysis were performed in the tissue microarrays, constructed from the 240 patients who were randomly selected. MET overexpression (IHC 3+) was observed in 6.0% (49/816) of the cohort. MET overexpression rate was higher in patients with poor prognostic factors, such as clinical stages III/IV (p =0.012) and pathologic stages T3/T4 (p =0.027). The HER2 overexpression (IHC 3+) rate was 8.8% (72/816) and MET overexpression rate was higher in HER2 positive patients (9.7%, 7/72). A high concordance rate (94.6%) between MET overexpression and gene amplification was demonstrated. Therefore, MET overexpression could serve as a prognostic biomarker and a potential therapeutic target for gastric cancer.

Mindfulness voor volwassenen met een licht verstandelijke beperking

NARCIS (Netherlands)

Punt, M.; Helmond, P.E.; Meirmans, M.; Otten, R.; Speckens, A.E.M.

2016-01-01

Mensen met een licht verstandelijke beperking (LVB) hebben veelal te maken met een opeenstapeling van verschillende biologische, psychologische en sociale factoren, waardoor zij vijf tot zes keer meer kans hebben op het ontwikkelen van psychopathologie dan normaal begaafden (Allen, 2008; Buckles,

Anxiolytic effect of music exposure on BDNFMet/Met transgenic mice.

Science.gov (United States)

Li, Wen-Jing; Yu, Hui; Yang, Jian-Min; Gao, Jing; Jiang, Hong; Feng, Min; Zhao, Yu-Xia; Chen, Zhe-Yu

2010-08-06

Brain-derived neurotrophic factor (BDNF) has been reported to play important roles in the modulation of anxiety, mood stabilizers, and pathophysiology of affective disorders. Recently, a single nucleotide polymorphism (SNP) in the BDNF gene (Val66Met) has been found to be associated with depression and anxiety disorders. The humanized BDNF(Met/Met) knock-in transgenic mice exhibited increased anxiety-related behaviors that were unresponsive to serotonin reuptake inhibitors, fluoxetine. Music is known to be able to elicit emotional changes, including anxiolytic effects. In this study, we found that music treatment could significantly decrease anxiety state in BDNF(Met/Met) mice, but not in BDNF(+/)(-), mice compared with white noise exposure in open field and elevated plus maze test. Moreover, in contrast to white noise exposure, BDNF expression levels in the prefrontal cortex (PFC), amygdala and hippocampus were significantly increased in music-exposed adult BDNF(Met/Met) mice. However, music treatment could not upregulate BDNF levels in the PFC, amygdala, and hippocampus in BDNF(+/)(-) mice, which suggests the essential role of BDNF in the anxiolytic effect of music. Together, our results imply that music may provide an effective therapeutic intervention for anxiety disorders in humans with this genetic BDNF(Met) variant. Copyright 2010 Elsevier B.V. All rights reserved.

Does dishonesty really invite third-party punishment? Results of a more stringent test.

Science.gov (United States)

Konishi, Naoki; Ohtsubo, Yohsuke

2015-05-01

Many experiments have demonstrated that people are willing to incur cost to punish norm violators even when they are not directly harmed by the violation. Such altruistic third-party punishment is often considered an evolutionary underpinning of large-scale human cooperation. However, some scholars argue that previously demonstrated altruistic third-party punishment against fairness-norm violations may be an experimental artefact. For example, envy-driven retaliatory behaviour (i.e. spite) towards better-off unfair game players may be misidentified as altruistic punishment. Indeed, a recent experiment demonstrated that participants ceased to inflict third-party punishment against an unfair player once a series of key methodological problems were systematically controlled for. Noticing that a previous finding regarding apparently altruistic third-party punishment against honesty-norm violations may have been subject to methodological issues, we used a different and what we consider to be a more sound design to evaluate these findings. Third-party punishment against dishonest players withstood this more stringent test. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Preproghrelin Leu72Met polymorphism in obese Korean children.

Science.gov (United States)

Jo, Dae-Sun; Kim, Se-Lim; Kim, Sun-Young; Hwang, Pyoung Han; Lee, Kee-Hyoung; Lee, Dae-Yeol

2005-11-01

Ghrelin is a novel gut-brain peptide that has somatotropic, orexigenic, and adipogenic effects. We examined the preproghrelin Leu72Met polymorphism in 222 obese Korean children to determine whether it is associated with obesity. The frequencies of the Leu72Met polymorphism were 29.3% in obese, 32.3% in overweight, and 32.5% in lean Korean children. No significant difference was found between Met72 carrier and non-carrier obese children with respect to BMI, total body fat, serum triglycerides, total cholesterol, or LDL-cholesterol levels. Our data suggest that the preproghrelin Leu72Met polymorphism is not associated with obesity in children.

Effect of MET on formation and vigor of wheat roots

International Nuclear Information System (INIS)

Wang Bingkui; Jin Ziyu; Zhao Miaozhen; Zhao Yanshen

1993-01-01

Effect of MET on the formation and vigor of roots of wheat seedlings were studied. The results showed that 50 ∼ 200 ppm MET inhibited vertical elongation of roots, increased root, shoot ratio and enhanced the formation and vigor of roots. But MET had no effect on the dry weight of roots. The activity of peroxidase was decreased and the proportion of assimilates in roots was increased by MET treatment compared with the control

Deelname aan de samenleving van mensen met een beperking: participatiemonitor 2007.

NARCIS (Netherlands)

Hoogen, P. van den; Cardol, M.; Speet, M.; Spreeuwenberg, P.; Rijken, M.

2008-01-01

Hoe doen mensen met een beperking mee in de maatschappij? Mensen met een lichamelijke beperking wonen en werken meestal net als iedereen, en ook zij zijn niet altijd tevreden met hun werk. Mensen met een verstandelijke beperking wonen en werken vaak in een speciale omgeving. Het overheidsbeleid

{sup 89}Zr-Onartuzumab PET imaging of c-MET receptor dynamics

Energy Technology Data Exchange (ETDEWEB)

Pool, Martin; Kol, Arjan; Giesen, Danique; Vries, Elisabeth G.E. de [University of Groningen, Department of Medical Oncology, University Medical Center Groningen, Groningen (Netherlands); Terwisscha van Scheltinga, Anton G.T. [University of Groningen, Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen (Netherlands); Lub-de Hooge, Marjolijn N. [University of Groningen, Department of Clinical Pharmacy and Pharmacology, University Medical Center Groningen, Groningen (Netherlands); University of Groningen, Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, Groningen (Netherlands)

2017-08-15

c-MET and its ligand hepatocyte growth factor are often dysregulated in human cancers. Dynamic changes in c-MET expression occur and might predict drug efficacy or emergence of resistance. Noninvasive visualization of c-MET dynamics could therefore potentially guide c-MET-directed therapies. We investigated the feasibility of {sup 89}Zr-labelled one-armed c-MET antibody onartuzumab PET for detecting relevant changes in c-MET levels induced by c-MET-mediated epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib resistance or heat shock protein-90 (HSP90) inhibitor NVP-AUY-922 treatment in human non-small-cell lung cancer (NSCLC) xenografts. In vitro membrane c-MET levels were determined by flow cytometry. HCC827ErlRes, an erlotinib-resistant clone with c-MET upregulation, was generated from the exon-19 EGFR-mutant human NSCLC cell line HCC827. Mice bearing HCC827 and HCC827ErlRes tumours in opposite flanks underwent {sup 89}Zr-onartuzumab PET scans. The HCC827-xenografted mice underwent {sup 89}Zr-onartuzumab PET scans before treatment and while receiving biweekly intraperitoneal injections of 100 mg/kg NVP-AUY-922 or vehicle. Ex vivo, tumour c-MET immunohistochemistry was correlated with the imaging results. In vitro, membrane c-MET was upregulated in HCC827ErlRes tumours by 213 ± 44% in relation to the level in HCC827 tumours, while c-MET was downregulated by 69 ± 9% in HCC827 tumours following treatment with NVP-AUY-922. In vivo, {sup 89}Zr-onartuzumab uptake was 26% higher (P < 0.05) in erlotinib-resistant HCC827ErlRes than in HCC827 xenografts, while HCC827 tumour uptake was 33% lower (P < 0.001) following NVP-AUY-922 treatment. The results show that {sup 89}Zr-onartuzumab PET effectively discriminates relevant changes in c-MET levels and could potentially be used clinically to monitor c-MET status. (orig.)

Ran GTPase promotes cancer progression via Met receptor-mediated downstream signaling

Science.gov (United States)

Yuen, Hiu-Fung; Chan, Ka-Kui; Platt-Higgins, Angela; Dakir, El-Habib; Matchett, Kyle B.; Haggag, Yusuf Ahmed; Jithesh, Puthen V.; Habib, Tanwir; Faheem, Ahmed; Dean, Fennell A.; Morgan, Richard; Rudland, Philip S.; El-Tanani, Mohamed

2016-01-01

It has been shown previously that cancer cells with an activated oncogenic pathway, including Met activation, require Ran for growth and survival. Here, we show that knockdown of Ran leads to a reduction of Met receptor expression in several breast and lung cancer cell lines. This, in turn suppressed HGF expression and the Met-mediated activation of the Akt pathway, as well as cell adhesion, migration, and invasion. In a cell line model where Met amplification has previously been shown to contribute to gefitinib resistance, Ran knockdown sensitized cells to gefitinib-mediated inhibition of Akt and ERK1/2 phosphorylation and consequently reduced cell proliferation. We further demonstrate that Met reduction-mediated by knockdown of Ran, occurs at the post-transcriptional level, probably via a matrix metalloproteinase. Moreover, the level of immunoreactive Ran and Met are positively associated in human breast cancer specimens, suggesting that a high level of Ran may be a pre-requisite for Met overexpression. Interestingly, a high level of immunoreactive Ran dictates the prognostic significance of Met, indicating that the co-overexpression of Met and Ran may be associated with cancer progression and could be used in combination as a prognostic indicator. PMID:27716616

Met .naturalis in zee: Nederlands koraalrifonderzoek in de Indo-Pacific

NARCIS (Netherlands)

Hoeksema, B.W.

2003-01-01

In een serie arikelen onder de naam 'Met Naturalis in zee', zal Onderwatersport in samenwerking met het Leidse museum Naturalis met enige regelmaat aandacht besteden aan Nederlands biologisch koraalrifonderzoek in de Indische en de Stille Oceaan. Bert Hoeksema schreef de introductie van de serie.

Effects of the BDNF Val66Met Polymorphism and Met Allele Load on Declarative Memory Related Neural Networks

OpenAIRE

Dodds, Chris M.; Henson, Richard N.; Suckling, John; Miskowiak, Kamilla W.; Ooi, Cinly; Tait, Roger; Soltesz, Fruzsina; Lawrence, Phil; Bentley, Graham; Maltby, Kay; Skeggs, Andrew; Miller, Sam R.; McHugh, Simon; Bullmore, Edward T.; Nathan, Pradeep J.

2013-01-01

It has been suggested that the BDNF Val66Met polymorphism modulates episodic memory performance via effects on hippocampal neural circuitry. However, fMRI studies have yielded inconsistent results in this respect. Moreover, very few studies have examined the effect of met allele load on activation of memory circuitry. In the present study, we carried out a comprehensive analysis of the effects of the BDNF polymorphism on brain responses during episodic memory encoding and retrieval, including...

Deelname aan de samenleving van mensen met een beperking: participatiemonitor 2007.

OpenAIRE

Hoogen, P. van den; Cardol, M.; Speet, M.; Spreeuwenberg, P.; Rijken, M.

2008-01-01

Hoe doen mensen met een beperking mee in de maatschappij? Mensen met een lichamelijke beperking wonen en werken meestal net als iedereen, en ook zij zijn niet altijd tevreden met hun werk. Mensen met een verstandelijke beperking wonen en werken vaak in een speciale omgeving. Het overheidsbeleid is erop gericht dat iedereen – dus ook mensen met een beperking – zoveel mogelijk ‘gewoon mee kan doen’ in de maatschappij. Bijvoorbeeld werken bij een gewone werkgever, schoolgaan op een gewone school...

Radiation Chemical Studies of Gly-Met-Gly in Aqueous Solution

NARCIS (Netherlands)

Barata-Vallejo, Sebastian; Ferreri, Carla; Zhang, Tao; Permentier, Hjalmar; Bischoff, Rainer; Bobrowski, Krzysztof; Chatgilialoglu, Chryssostomos

2016-01-01

Important biological consequences are related to the reaction of HO(•) radicals with methionine (Met). Several fundamental aspects remain to be defined when Met is an amino acid residue incorporated in the interior of peptides and proteins. The present study focuses on Gly-Met-Gly, the simplest

Gender fairness in self-efficacy? A Rasch-based validity study of the General Academic Self-efficacy scale (GASE)

DEFF Research Database (Denmark)

Nielsen, Tine; Vang, Maria Louison; Dammeyer, Jesper

2018-01-01

Studies have reported gender differences in academic self-efficacy. However, how and if academic self-efficacy questionnaires are gender-biased has not been psychometrically investigated. The psychometric properties of a general version of The Physics Self-Efficacy Questionnaire – the General...... Academic Self-Efficacy Scale (GASE) – were analyzed using Rasch measurement models, with data from 1018 Danish university students (psychology and technical), focusing on gender invariance and the sufficiency of the score. The short 4-item GASE scale was found to be essentially objective and construct...... valid and satisfactorily reliable, though differential item functioning was found relative to gender and academic discipline, and can be used to assess students’ general academic self-efficacy. Research on gender and self-efficacy needs to take gender into account and equate scores appropriately...

Lack of neural compensatory mechanisms of BDNF val66met met carriers and APOE E4 carriers in healthy aging, mild cognitive impairment, and Alzheimer's disease.

Science.gov (United States)

Gomar, Jesus J; Conejero-Goldberg, Concepcion; Huey, Edward D; Davies, Peter; Goldberg, Terry E

2016-03-01

Compromises in compensatory neurobiologic mechanisms due to aging and/or genetic factors (i.e., APOE gene) may influence brain-derived neurotrophic factor (BDNF) val66met polymorphism effects on temporal lobe morphometry and memory performance. We studied 2 cohorts from Alzheimer's Disease Neuroimaging Initiative: 175 healthy subjects and 222 with prodromal and established Alzheimer's disease. Yearly structural magnetic resonance imaging and cognitive performance assessments were carried out over 3 years of follow-up. Both cohorts had similar BDNF Val/Val and Met allele carriers' (including both Val/Met and Met/Met individuals) distribution. In healthy subjects, a significant trend for thinner posterior cingulate and precuneus cortices was detected in Met carriers compared to Val homozygotes in APOE E4 carriers, with large and medium effect sizes, respectively. The mild cognitive impairment/Alzheimer's disease cohort showed a longitudinal decline in entorhinal thickness in BDNF Met carriers compared to Val/Val in APOE E4 carriers, with effect sizes ranging from medium to large. In addition, an effect of BDNF genotype was found in APOE E4 carriers for episodic memory (logical memory and ADAS-Cog) and semantic fluency measures, with Met carriers performing worse in all cases. These findings suggest a lack of compensatory mechanisms in BDNF Met carriers and APOE E4 carriers in healthy and pathological aging. Copyright © 2016 Elsevier Inc. All rights reserved.

Mars MetNet Mission - Martian Atmospheric Observational Post Network

Science.gov (United States)

Harri, A.-M.; Haukka, H.; Aleksashkin, S.; Arruego, I.; Schmidt, W.; Genzer, M.; Vazquez, L.; Siikonen, T.; Palin, M.

2017-09-01

A new kind of planetary exploration mission for Mars is under development in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semi-hard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested.

A comparison of three methods of assessing differential item functioning (DIF) in the Hospital Anxiety Depression Scale: ordinal logistic regression, Rasch analysis and the Mantel chi-square procedure.

Science.gov (United States)

Cameron, Isobel M; Scott, Neil W; Adler, Mats; Reid, Ian C

2014-12-01

It is important for clinical practice and research that measurement scales of well-being and quality of life exhibit only minimal differential item functioning (DIF). DIF occurs where different groups of people endorse items in a scale to different extents after being matched by the intended scale attribute. We investigate the equivalence or otherwise of common methods of assessing DIF. Three methods of measuring age- and sex-related DIF (ordinal logistic regression, Rasch analysis and Mantel χ(2) procedure) were applied to Hospital Anxiety Depression Scale (HADS) data pertaining to a sample of 1,068 patients consulting primary care practitioners. Three items were flagged by all three approaches as having either age- or sex-related DIF with a consistent direction of effect; a further three items identified did not meet stricter criteria for important DIF using at least one method. When applying strict criteria for significant DIF, ordinal logistic regression was slightly less sensitive. Ordinal logistic regression, Rasch analysis and contingency table methods yielded consistent results when identifying DIF in the HADS depression and HADS anxiety scales. Regardless of methods applied, investigators should use a combination of statistical significance, magnitude of the DIF effect and investigator judgement when interpreting the results.

El acertijo de la metáfora visual

OpenAIRE

De la Rosa Alzate, Adriana; Universidad Autónoma de Occidente

2016-01-01

En este artículo se presentan los resultados de la investigación sobre el proceso de interpretación de la metáfora visual, en niños entre tres y cuatro años de edad. El propósito de la investigación fue dar cuenta del proceso de interpretación de la metáfora visual y del razonamiento involucrado. La metáfora visual se entiende como un fenómeno en el que los objetos representados presentan transformaciones que traen como consecuencia la emergencia de nuevas categorías e incluso la ambigüedad, ...

Resultaten boomkorsurvey 2013: BTS met onderzoeksvaartuigen Isis en Tridens (interview met Ingeborg de Boois)

NARCIS (Netherlands)

Boois, de I.J.

2013-01-01

Van begin augustus tot half september heeft IMARES de boomkorsurvey (BTS) uitgevoerd met de onderzoeksschepen Isis en Tridens. Op 29 maart 2014 wordt een bijeenkomst georganiseerd voor geinteresseerden, waar de resultaten van zowel de BTS als de bedrijfssurvey gepresenteerd worden. De BTS wordt

Preliminary study to evaluate the validity of the mini-mental state examination in a normal population in Turkey.

Science.gov (United States)

Küçükdeveci, Ayse A; Kutlay, Sehim; Elhan, Atilla H; Tennant, Alan

2005-03-01

Although the Mini-Mental State Examination (MMSE) is widely used in clinical practice, normative scores for a healthy population have not been documented in Turkey. The aim in this study was to validate the MMSE in a healthy population and to provide normal scores. Internal construct validity of the Turkish version of MMSE among a preliminary sample of 406 normal people was assessed by Rasch unidimensional measurement model. Scores of the normal sample varied according to age and education but not according to sex. The data derived from this sample showed poor fit to the Rasch model (mean item fit, -2.082, SD 3.022). Only four of 11 items met model expectations. There was also differential item functioning by education and age for most items. Thus the internal construct validity of the Turkish MMSE in a normative sample could not be demonstrated by Rasch analysis. The scale failed modern psychometric criteria for scalability. We would therefore suggest other large normative MMSE data sets to be tested in terms of internal construct validity. If these findings are replicated, the validity of MMSE norms and their consequent use in clinical practice should be reconsidered.

Measuring practical knowledge about balanced meals: development and validation of the brief PKB-7 scale.

Science.gov (United States)

Mötteli, S; Barbey, J; Keller, C; Bucher, T; Siegrist, M

2016-04-01

As a high-quality diet is associated with a lower risk for several diseases and all-cause mortality, current nutrition education tools provide people with information regarding how to build a healthy and a balanced meal. To assess this basic nutrition knowledge, the research aim was to develop and validate a brief scale to measure the Practical Knowledge about Balanced meals (PKB-7). A pool of 25 items was pretested with experts and laypeople before being tested on a random sample in Switzerland (n=517). For item selection, a Rasch model analysis was applied. The validity and reliability of the new scale were assessed by three additional studies including laypeople (n=597; n=145) and nutrition experts (n=59). The final scale consists of seven multiple-choice items, which met the assumptions of the Rasch model. The validity of the new scale was shown by several aspects: the Rasch model was replicated in a second study, and nutrition experts achieved significantly higher scores than laypeople (t(148)=20.27, Pbalanced meals based on current dietary guidelines. This brief and easy-to-use scale is intended for application in both research and practice.

La metáfora

DEFF Research Database (Denmark)

Agustin, Oscar Garcia

2007-01-01

2002 y principios de 2003, anteriores a la proclamación de las Juntas de Buen Gobierno. Nuestro objetivo es comprobar cómo las metáforas crean nuevas significaciones, que intentan deshacer una lógica comúnmente asumida, y promover otros modos de comprender la acción y la realidad político-social. Este...

Measuring health-related problem solving among African Americans with multiple chronic conditions: application of Rasch analysis.

Science.gov (United States)

Fitzpatrick, Stephanie L; Hill-Briggs, Felicia

2015-10-01

Identification of patients with poor chronic disease self-management skills can facilitate treatment planning, determine effectiveness of interventions, and reduce disease complications. This paper describes the use of a Rasch model, the Rating Scale Model, to examine psychometric properties of the 50-item Health Problem-Solving Scale (HPSS) among 320 African American patients with high risk for cardiovascular disease. Items on the positive/effective HPSS subscales targeted patients at low, moderate, and high levels of positive/effective problem solving, whereas items on the negative/ineffective problem solving subscales mostly targeted those at moderate or high levels of ineffective problem solving. Validity was examined by correlating factor scores on the measure with clinical and behavioral measures. Items on the HPSS show promise in the ability to assess health-related problem solving among high risk patients. However, further revisions of the scale are needed to increase its usability and validity with large, diverse patient populations in the future.

Metáforas metalinguísticas de Euclides da Cunha

Directory of Open Access Journals (Sweden)

Carlos Antônio Magalhães Guedelha

2016-03-01

Full Text Available Este artigo apresenta uma leitura das metáforas metalinguísticas do escritor Euclides da Cunha, ou seja, as metáforas que ele utilizou para se referir aos seus dois principais livros, Os Sertões (sobre a guerra de Canudos e Um paraíso perdido (sobre a Amazônia. O conceito de metalinguagem estabelecido por Jakobson foi fundamental para a pesquisa, que teve como suporte teórico básico o postulado da metáfora conceptual, proposta por Lakoff e Johnson. As metáforas analisados neste artigo (VINGAR-SE É ESCREVER e UM LIVRO É UM FILHO foram colhidas de ensaios do escritor e de cartas que ele escreveu a amigos e familiares, “escriturando” a sua escrita por meio da metalinguagem. A análise das metáforas assume, com base em Lakoff e Johnson, que a metáfora não é uma questão apenas de linguagem. Ela é também – e fundamentalmente – uma questão de pensamento e ação.

MetReS, an Efficient Database for Genomic Applications.

Science.gov (United States)

Vilaplana, Jordi; Alves, Rui; Solsona, Francesc; Mateo, Jordi; Teixidó, Ivan; Pifarré, Marc

2018-02-01

MetReS (Metabolic Reconstruction Server) is a genomic database that is shared between two software applications that address important biological problems. Biblio-MetReS is a data-mining tool that enables the reconstruction of molecular networks based on automated text-mining analysis of published scientific literature. Homol-MetReS allows functional (re)annotation of proteomes, to properly identify both the individual proteins involved in the processes of interest and their function. The main goal of this work was to identify the areas where the performance of the MetReS database performance could be improved and to test whether this improvement would scale to larger datasets and more complex types of analysis. The study was started with a relational database, MySQL, which is the current database server used by the applications. We also tested the performance of an alternative data-handling framework, Apache Hadoop. Hadoop is currently used for large-scale data processing. We found that this data handling framework is likely to greatly improve the efficiency of the MetReS applications as the dataset and the processing needs increase by several orders of magnitude, as expected to happen in the near future.

Role of Met Axis in Head and Neck Cancer

Energy Technology Data Exchange (ETDEWEB)

Xu, Yiru, E-mail: xuyiru@umich.edu; Fisher, Gary J., E-mail: xuyiru@umich.edu [Department of Dermatology, University of Michigan, Ann Arbor, MI 48109 (United States)

2013-11-26

Head and neck cancer is the sixth most common type of cancer worldwide. Despite advances in aggressive multidisciplinary treatments, the 5-year survival rate for this dreadful disease is only 50%, mostly due to high rate of recurrence and early involvement of regional lymph nodes and subsequent metastasis. Understanding the molecular mechanisms responsible for invasion and metastasis is one of the most pressing goals in the field of head and neck cancer. Met, also known as hepatocyte growth factor receptor (HGFR), is a member of the receptor protein tyrosine kinase (RPTK) family. There is compelling evidence that Met axis is dysregulated and plays important roles in tumorigenesis, progression, metastasis, angiogenesis, and drug resistance in head and neck cancer. We describe in this review current understanding of Met axis in head and neck cancer biology and development of therapeutic inhibitors targeting Met axis.

Construct validity in Operations Management by using Rasch Measurement Theory. The case of the construct “motivation to implement continuous improvement"

Directory of Open Access Journals (Sweden)

Lidia Sanchez-Ruiz

2016-12-01

Full Text Available Construct design and validation is a common practise in the Operations Management field. In this sense, the aim of this study is to present Rasch Measurement Theory (RMT as richful and useful methodology in order to validate constructs. In order to do so, the measurement controversy in the social science is presented; then, RMT is explained as a solution for this measurement issue; after that, the different applications of RMT are described and, finally, the different stages of the validation process are presented. Thus, this work aims to serve as a guide for those researchers interested in the methodology. Therefore, a specific case is included: the validation of the construct “motivation to implement continuous improvement”.

11C-MET PET/MRI for detection of recurrent glioma.

Science.gov (United States)

Deuschl, C; Kirchner, J; Poeppel, T D; Schaarschmidt, B; Kebir, S; El Hindy, N; Hense, J; Quick, H H; Glas, M; Herrmann, K; Umutlu, L; Moenninghoff, C; Radbruch, A; Forsting, M; Schlamann, M

2018-04-01

Radiological assessment of brain tumors is widely based on the Radiology Assessment of Neuro-Oncology (RANO) criteria that consider non-specific T1 and T2 weighted images. Limitation of the RANO criteria is that they do not include metabolic imaging techniques that have been reported to be helpful to differentiate treatment related changes from true tumor progression. In the current study, we assessed if the combined use of MRI and PET with hybrid 11 C-MET PET/MRI can improve diagnostic accuracy and diagnostic confidence of the readers to differentiate treatment related changes from true progression in recurrent glioma. Fifty consecutive patients with histopathologically proven glioma were prospectively enrolled for a hybrid 11 C-MET PET/MRI to differentiate recurrent glioma from treatment induced changes. Sole MRI data were analyzed based on RANO. Sole PET data and in a third evaluation hybrid 11 C-MET-PET/MRI data were assessed for metabolic respectively metabolic and morphologic glioma recurrence. Diagnostic performance and diagnostic confidence of the reader were calculated for the different modalities, and the McNemar test and Mann-Whitney U Test were applied for statistical analysis. Hybrid 11 C-MET PET/MRI was successfully performed in all 50 patients. Glioma recurrence was diagnosed in 35 of the 50 patients (70%). Sensitivity and specificity were calculated for MRI (86.11% and 71.43%), for 11 C-MET PET (96.77% and 73.68%), and for hybrid 11 C-MET-PET/MRI (97.14% and 93.33%). For diagnostic accuracy hybrid 11 C-MET-PET/MRI (96%) showed significantly higher values than MRI alone (82%), whereas no significant difference was found for 11C-MET PET (88%). Furthermore, by rating on a five-point Likert scale significantly higher scores were found for diagnostic confidence when comparing 11 C-MET PET/MRI (4.26 ± 0,777) to either PET alone (3.44 ± 0.705) or MRI alone (3.56 ± 0.733). This feasibility study showed that hybrid PET/MRI might strengthen

Invloed krachtvoerniveau op vleesproduktiekenmerken van Piemontese met zwartbont kruislingstieren

NARCIS (Netherlands)

Hanekamp, W.J.A.

1989-01-01

Met 3 ronden van elk 36 Piemontese X zwartbonte kruislingstieren is het effect van extra krachtvoer vergeleken met de normaal gangbare gift naast onbeperkt snijmaoskuil. De stieren waren gehuisvest in een natuurlijk geventileerde stal (space-boarding)en op een volledige roostervloer.

Pastoors naar de PFA: nieuwe impuls voor samenwerking met de wetenschap (interview met Martin Pastoors)

NARCIS (Netherlands)

Pastoors, M.A.

2014-01-01

De Pelagic Freezer-trawler Association (PFA) heeft visserijonderzoeler Martin Pastoors aangenomen als 'Chief Science Officer'. De afgelopen tien jaar is de PFA zich steeds meer bezig gaan houden met wetenschappelijk onderzoek. Bijvoorbeeld door het ontwikkelen van nieuwe manieren om data te

Met Ed gets reprieve: banks lend tax money

International Nuclear Information System (INIS)

Utroska, D.

1981-01-01

A consortium of banks agreed to loan Metropolitan Edison $23 million to pay its April 15 state taxes and temporarily relieve a cash-flow problem that is leading to default after the Pennsylvania Public Utility Commission expedited a rate request. The continued solvency of Met Ed is a matter of speculation because the present credit formula is based on liquid assets which the PUC did not address. While the action taken by the bankers gives Met Ed a reprieve, it does not provide a long-term solution. The Revolving Credit Agreement will expire on October 1. Met Ed is still faced with the problem of relicensing Three Mile Island-1 unit and the cost of underwriting the cleanup of the No. 2 unit

Recent advances in the discovery of small molecule c-Met Kinase inhibitors.

Science.gov (United States)

Parikh, Palak K; Ghate, Manjunath D

2018-01-01

c-Met is a prototype member of a subfamily of heterodimeric receptor tyrosine kinases (RTKs) and is the receptor for hepatocyte growth factor (HGF). Binding of HGF to its receptor c-Met, initiates a wide range of cellular signalling, including those involved in proliferation, motility, migration and invasion. Importantly, dysregulated HGF/c-Met signalling is a driving factor for numerous malignancies and promotes tumour growth, invasion, dissemination and/or angiogenesis. Dysregulated HGF/c-Met signalling has also been associated with poor clinical outcomes and resistance acquisition to some approved targeted therapies. Thus, c-Met kinase has emerged as a promising target for cancer drug development. Different therapeutic approaches targeting the HGF/c-Met signalling pathway are under development for targeted cancer therapy, among which small molecule inhibitors of c-Met kinase constitute the largest effort within the pharmaceutical industry. The review is an effort to summarize recent advancements in medicinal chemistry development of small molecule c-Met kinase inhibitors as potential anti-cancer agents which would certainly help future researchers to bring further developments in the discovery of small molecule c-Met kinase inhibitors. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Design and synthesis of 3,3'-biscoumarin-based c-Met inhibitors.

Science.gov (United States)

Xu, Jimin; Ai, Jing; Liu, Sheng; Peng, Xia; Yu, Linqian; Geng, Meiyu; Nan, Fajun

2014-06-14

A library of biscoumarin-based c-Met inhibitors was synthesized, based on optimization of 3,3'-biscoumarin hit 3, which was identified as a non-ATP competitive inhibitor of c-Met from a diverse library of coumarin derivatives. Among these compounds, 38 and 40 not only showed potent enzyme activities with IC50 values of 107 nM and 30 nM, respectively, but also inhibited c-Met phosphorylation in BaF3/TPR-Met and EBC-1 cells.

Metáfora y estructura conceptual

Directory of Open Access Journals (Sweden)

Emilia Castaño

2012-01-01

Full Text Available La lingüística cognitiva siempre ha argumentado que la metáfora no pertenece exclusivamente al lenguaje, sino que es una competencia que se basa en la habilidad humana de concebir un dominio de experiencia en términos de otro. Entendida así, la metáfora no puede ser otra cosa que un fenómeno conceptual. No obstante, pocos adeptos de la lingüística cognitiva han concentrados sus esfuerzos en catalogar manifestaciones metafóricas en ámbitos no lingüísticos. En este trabajo, sugerimos que es factible encontrar pruebas de que la metáfora es un proceso conceptual y, como tal, se manifiesta en esferas que no son estrictamente lingüísticas. Para ello, aportamos un seguido de evidencias muy diversas, como por ejemplo su papel en el razonamiento lógico-matemático de los niños en la fase preoperacional del desarrollo cognitivo, la programación de interfaces para aplicaciones informáticas y los resultados de tres estudios empíricos realizados recientemente en el campo  de la psicología cognitiva que analizan los efectos whorfianos en la conceptualización del tiempo y los efectos del espacio en la memoria emocional.

Activated HGF-c-Met Axis in Head and Neck Cancer

Directory of Open Access Journals (Sweden)

Levi Arnold

2017-12-01

Full Text Available Head and neck squamous cell carcinoma (HNSCC is a highly morbid disease. Recent developments including Food and Drug Administration (FDA approved molecular targeted agent’s pembrolizumab and cetuximab show promise but did not improve the five-year survival which is currently less than 40%. The hepatocyte growth factor receptor; also known as mesenchymal–epithelial transition factor (c-Met and its ligand hepatocyte growth factor (HGF are overexpressed in head and neck squamous cell carcinoma (HNSCC; and regulates tumor progression and response to therapy. The c-Met pathway has been shown to regulate many cellular processes such as cell proliferation, invasion, and angiogenesis. The c-Met pathway is involved in cross-talk, activation, and perpetuation of other signaling pathways, curbing the cogency of a blockade molecule on a single pathway. The receptor and its ligand act on several downstream effectors including phospholipase C gamma (PLCγ, cellular Src kinase (c-Src, phosphotidylinsitol-3-OH kinase (PI3K alpha serine/threonine-protein kinase (Akt, mitogen activate protein kinase (MAPK, and wingless-related integration site (Wnt pathways. They are also known to cross-talk with other receptors; namely epidermal growth factor receptor (EGFR and vascular endothelial growth factor receptor (VEGFR and specifically contribute to treatment resistance. Clinical trials targeting the c-Met axis in HNSCC have been undertaken because of significant preclinical work demonstrating a relationship between HGF/c-Met signaling and cancer cell survival. Here we focus on HGF/c-Met impact on cellular signaling in HNSCC to potentiate tumor growth and disrupt therapeutic efficacy. Herein we summarize the current understanding of HGF/c-Met signaling and its effects on HNSCC. The intertwining of c-Met signaling with other signaling pathways provides opportunities for more robust and specific therapies, leading to better clinical outcomes.

Anti-c-MET Nanobody - a new potential drug in multiple myeloma treatment.

Science.gov (United States)

Slørdahl, Tobias Schmidt; Denayer, Tinneke; Moen, Siv Helen; Standal, Therese; Børset, Magne; Ververken, Cedric; Rø, Torstein Baade

2013-11-01

c-MET is the tyrosine kinase receptor of the hepatocyte growth factor (HGF). HGF-c-MET signaling is involved in many human malignancies, including multiple myeloma (MM). Recently, multiple agents have been developed directed to interfere at different levels in HGF-c-MET signaling pathway. Nanobodies are therapeutic proteins based on the smallest functional fragments of heavy-chain-only antibodies. In this study, we wanted to determine the anticancer effect of a novel anti-c-MET Nanobody in MM. We examined the effects of an anti-c-MET Nanobody on thymidine incorporation, migration, adhesion of MM cells, and osteoblastogenesis in vitro. Furthermore, we investigated the effects of the Nanobody on HGF-dependent c-MET signaling by Western blotting. We show that the anti-c-MET Nanobody effectively inhibited thymidine incorporation of ANBL-6 MM cells via inhibition of an HGF autocrine growth loop and thymidine incorporation in INA-6 MM cells induced by exogenous HGF. HGF-induced migration and adhesion of INA-6 were completely and specifically blocked by the Nanobody. Furthermore, the Nanobody abolished the inhibiting effect of HGF on bone morphogenetic protein-2-induced alkaline phosphatase activity and the mineralization of human mesenchymal stem cells. Finally, we show that the Nanobody reduced phosphorylation of tyrosine residues in c-MET, MAPK, and Akt. We also compared the Nanobody with anti-c-MET monoclonal antibodies and revealed the similar or better effect. The anti-c-MET Nanobody inhibited MM cell migration, thymidine incorporation, and adhesion, and blocked the HGF-mediated inhibition of osteoblastogenesis. The anti-c-MET Nanobody might represent a novel therapeutic agent in the treatment of MM and other cancers driven by HGF-c-MET signaling. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Measurement properties of the Health Literacy Questionnaire (HLQ) among older adults who present to the emergency department after a fall: a Rasch analysis.

Science.gov (United States)

Morris, Rebecca L; Soh, Sze-Ee; Hill, Keith D; Buchbinder, Rachelle; Lowthian, Judy A; Redfern, Julie; Etherton-Beer, Christopher D; Hill, Anne-Marie; Osborne, Richard H; Arendts, Glenn; Barker, Anna L

2017-08-29

Health literacy is an important concept associated with participation in preventive health initiatives, such as falls prevention programs. A comprehensive health literacy measurement tool, appropriate for this population, is required. The aim of this study was to evaluate the measurement properties of the Health Literacy Questionnaire (HLQ) in a cohort of older adults who presented to a hospital emergency department (ED) after a fall. Older adults who presented to an ED after a fall had their health literacy assessed using the HLQ (n = 433). Data were collected as part of a multi-centre randomised controlled trial of a falls prevention program. Measurement properties of the HLQ were assessed using Rasch analysis. All nine scales of the HLQ were unidimensional, with good internal consistency reliability. No item bias was found for most items (43 of 44). A degree of overall misfit to the Rasch model was evident for six of the nine HLQ scales. The majority of misfit indicated content overlap between some items and does not compromise measurement. A measurement gap was identified for this cohort at mid to high HLQ score. The HLQ demonstrated good measurement properties in a cohort of older adults who presented to an ED after a fall. The summation of the HLQ items within each scale, providing unbiased information on nine separate areas of health literacy, is supported. Clinicians, researchers and policy makers may have confidence using the HLQ scale scores to gain information about health literacy in older people presenting to the ED after a fall. This study was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12614000336684 (27 March 2014).

Mogelijkheden om vroeg tijdig bladrandproblemen te signaleren met MIPS bij Hortensia

NARCIS (Netherlands)

Noort, van F.R.; Jalink, H.

2010-01-01

Met geavanceerde camera technieken zijn beelden vast te leggen van fotosynthese activiteit en het is ook mogelijk gebleken om bladgedeelten met stress vast te leggen, zonder dat deze stress met het blote oog al te zien is. Dit opent perspectieven om monitorringonderzoek te doen naar het ontstaan van

Design and Implementation of Image Research for the Columbia Mets

Science.gov (United States)

1992-01-01

the other hand, developed an unusual camaraderie through identifying with their underdog Mets." (7) Teams are finding good public relations programs do...supports the club. Question 24 was designed to measure brand loyalty by respondents to Mets sponsors versus non-Mets sponsors. Finally, question 27...be done to attract crowds. Especially with a brand new stadium. The Carolinas, in my opinion, are big minor league baseball states. Let’s get people

Alternative Fuels Data Center: Workplace Charging Success: MetLife

Science.gov (United States)

future." Several others noted that their decision to purchase or lease a PEV was based on MetLife's : MetLife " By making PEV charging stations more readily available to employees, we can encourage more promote alternative transportation. By making PEV charging stations more readily available to employees

Developing a Measure of Therapist Adherence to Contingency Management: An Application of the Many-Facet Rasch Model.

Science.gov (United States)

Chapman, Jason E; Sheidow, Ashli J; Henggeler, Scott W; Halliday-Boykins, Colleen; Cunningham, Phillippe B

2008-06-01

A unique application of the Many-Facet Rasch Model (MFRM) is introduced as the preferred method for evaluating the psychometric properties of a measure of therapist adherence to Contingency Management (CM) treatment of adolescent substance use. The utility of psychometric methods based in Classical Test Theory was limited by complexities of the data, including: (a) ratings provided by multiple informants (i.e., youth, caregivers, and therapists), (b) data from separate research studies, (c) repeated measurements, (d) multiple versions of the questionnaire, and (e) missing data. Two dimensions of CM adherence were supported: adherence to Cognitive Behavioral components and adherence to Monitoring components. The rating scale performed differently for items in these subscales, and of 11 items evaluated, eight were found to perform well. The MFRM is presented as a highly flexible approach that can be used to overcome the limitations of traditional methods in the development of adherence measures for evidence-based practices.

Cetuximab-Induced MET Activation Acts as a Novel Resistance Mechanism in Colon Cancer Cells

Directory of Open Access Journals (Sweden)

Na Song

2014-04-01

Full Text Available Aberrant MET expression and hepatocyte growth factor (HGF signaling are implicated in promoting resistance to targeted agents; however, the induced MET activation by epidermal growth factor receptor (EGFR inhibitors mediating resistance to targeted therapy remains elusive. In this study, we identified that cetuximab-induced MET activation contributed to cetuximab resistance in Caco-2 colon cancer cells. MET inhibition or knockdown sensitized Caco-2 cells to cetuximab-mediated growth inhibition. Additionally, SRC activation promoted cetuximab resistance by interacting with MET. Pretreatment with SRC inhibitors abolished cetuximab-mediated MET activation and rendered Caco-2 cells sensitive to cetuximab. Notably, cetuximab induced MET/SRC/EGFR complex formation. MET inhibitor or SRC inhibitor suppressed phosphorylation of MET and SRC in the complex, and MET inhibitor singly led to disruption of complex formation. These results implicate alternative targeting of MET or SRC as rational strategies for reversing cetuximab resistance in colon cancer.

MetWAMer: eukaryotic translation initiation site prediction

Directory of Open Access Journals (Sweden)

Brendel Volker

2008-09-01

Full Text Available Abstract Background Translation initiation site (TIS identification is an important aspect of the gene annotation process, requisite for the accurate delineation of protein sequences from transcript data. We have developed the MetWAMer package for TIS prediction in eukaryotic open reading frames of non-viral origin. MetWAMer can be used as a stand-alone, third-party tool for post-processing gene structure annotations generated by external computational programs and/or pipelines, or directly integrated into gene structure prediction software implementations. Results MetWAMer currently implements five distinct methods for TIS prediction, the most accurate of which is a routine that combines weighted, signal-based translation initiation site scores and the contrast in coding potential of sequences flanking TISs using a perceptron. Also, our program implements clustering capabilities through use of the k-medoids algorithm, thereby enabling cluster-specific TIS parameter utilization. In practice, our static weight array matrix-based indexing method for parameter set lookup can be used with good results in data sets exhibiting moderate levels of 5'-complete coverage. Conclusion We demonstrate that improvements in statistically-based models for TIS prediction can be achieved by taking the class of each potential start-methionine into account pending certain testing conditions, and that our perceptron-based model is suitable for the TIS identification task. MetWAMer represents a well-documented, extensible, and freely available software system that can be readily re-trained for differing target applications and/or extended with existing and novel TIS prediction methods, to support further research efforts in this area.

Investigation of the prominent barriers to lean manufacturing implementation in Malaysian food and beverages industry using Rasch Model

Science.gov (United States)

Khusaini, N. S.; Ismail, A.; Rashid, A. A.

2016-02-01

This paper presents a preliminary study on the prominent barriers to lean manufacturing implementation in Malaysian Food and Beverages Industry. A survey was carried out to determine the most prominent barriers of lean manufacturing implementation that are currently being faced in this industry. The amount of barriers identified for this study is twenty seven. Out of 1309 available organizations, a total of 300 organizations have been randomly selected as respondents, and 53 organizations responded. From the variable map, the analysis shows that, the negative perception towards lean manufacturing top the list as the most agreeable barrier, while the technical barriers came after it. It can also be seen from the variable map that averagely, lack of vision and direction is the barrier that is being faced. Finally, this is perhaps the first attempt in investigating the prominent barriers to Lean Manufacturing implementation in Malaysian food and beverages industry using Rasch Model.

c-MET receptor tyrosine kinase as a molecular target in advanced hepatocellular carcinoma.

Science.gov (United States)

Granito, Alessandro; Guidetti, Elena; Gramantieri, Laura

2015-01-01

c-MET is the membrane receptor for hepatocyte growth factor (HGF), also known as scatter factor or tumor cytotoxic factor, a mitogenic growth factor for hepatocytes. HGF is mainly produced by cells of mesenchymal origin and it mainly acts on neighboring epidermal and endothelial cells, regulating epithelial growth and morphogenesis. HGF/MET signaling has been identified among the drivers of tumorigenesis in human cancers. As such, c-MET is a recognized druggable target, and against it, targeted agents are currently under clinical investigation. c-MET overexpression is a common event in a wide range of human malignancies, including gastric, lung, breast, ovary, colon, kidney, thyroid, and liver carcinomas. Despite c-MET overexpression being reported by a large majority of studies, no evidence for a c-MET oncogenic addiction exists in hepatocellular carcinoma (HCC). In particular, c-MET amplification is a rare event, accounting for 4%-5% of cases while no mutation has been identified in c-MET oncogene in HCC. Thus, the selection of patient subgroups more likely to benefit from c-MET inhibition is challenging. Notwithstanding, c-MET overexpression was reported to be associated with increased metastatic potential and poor prognosis in patients with HCC, providing a rationale for its therapeutic inhibition. Here we summarize the role of activated HGF/MET signaling in HCC, its prognostic relevance, and the implications for therapeutic approaches in HCC.

Prognostic impact of tumor MET expression among patients with stage IV gastric cancer

DEFF Research Database (Denmark)

Erichsen, Rune; Kelsh, Michael A; Oliner, Kelly S

2016-01-01

PURPOSE: We aimed to investigate the prevalence and prognostic impact of tumor mesenchymal epithelial transition factor (MET) expression in stage IV gastric cancers in a real-world clinical setting because existing evidence is sparse. METHODS: The study included archived cancer specimens from 103...... stage IV gastric cancer patients (2003-2010). We analyzed MET-protein expression by immunohistochemistry (MET-positive if ≥25% of tumor cells showed MET expression). We calculated overall survival using the Kaplan-Meier method and hazard ratios comparing mortality among MET-positive and MET.......6 months), corresponding to an adjusted hazard ratio of 2.2 (95% confidence interval, 1.3-3.7). CONCLUSIONS: Tumor MET expression is prevalent and has substantial prognostic impact in stage IV gastric cancer patients....

OTULIN antagonizes LUBAC signaling by specifically hydrolyzing met1-linked polyubiquitin

DEFF Research Database (Denmark)

Keusekotten, K.; Elliott, P.R.; Kulathu, Y.

2013-01-01

The linear ubiquitin (Ub) chain assembly complex (LUBAC) is an E3 ligase that specifically assembles Met1-linked (also known as linear) Ub chains that regulate nuclear factor κB (NF-κB) signaling. Deubiquitinases (DUBs) are key regulators of Ub signaling, but a dedicated DUB for Met1 linkages has...... not been identified. Here, we reveal a previously unannotated human DUB, OTULIN (also known as FAM105B), which is exquisitely specific for Met1 linkages. Crystal structures of the OTULIN catalytic domain in complex with diubiquitin reveal Met1-specific Ub-binding sites and a mechanism of substrate...

De Doop met de Heilige Geest

Directory of Open Access Journals (Sweden)

S. C.W. Duvenage.

1965-03-01

Full Text Available Ds. Molenaar begin sy boek, waarvan hy self die publikasienie beleef het nie, deur te wys op 'n groot tekort, ’n manko,nie alleen in die Gereformeerde vroomheid of lewe nie maarook in die Gereformeerde teologie. Hy beskou dit as hoogsmerkwaardig dat die Gereformeerde teologie in die verledeso goed as niks raakgesien het van die groot betekenis vandie sogenaamde doop met die Heilige Gees nie. Daarby meenhy dat die Gereformeerde predikante verleë sit met die Pinkterfees.Talle probleme meen hy vir die Gereformeerde teoloograak te sien, veral ten aansien van die moontlikhede van dieGees teenoor die so tasbare „onmoontIikhede” in ons lewe. Dieprobleme is syns insiens nie onoplosbaar nie, as mens maardie moontlikhede van die Gees nie beperk tot die verlede nie.

c-MET Overexpression in Colorectal Cancer: A Poor Prognostic Factor for Survival.

Science.gov (United States)

Lee, Su Jin; Lee, Jeeyun; Park, Se Hoon; Park, Joon Oh; Lim, Ho Yeong; Kang, Won Ki; Park, Young Suk; Kim, Seung Tae

2018-03-02

Increased mesenchymal-epithelial transition factor gene (c-MET) expression in several human malignancies is related to increased tumor progression and is a new potential drug target for several types of cancers. In the present study, we investigated the incidence of c-MET overexpression and its prognostic significance in patients with colorectal cancer (CRC). We retrospectively reviewed the data from 255 stage IV CRC patients who had results from a c-MET immunohistochemical test at Samsung Medical Center. We explored the relationships between c-MET overexpression and clinicopathological features and survival. Primary tumor sites were 67 right-sided colon, 98 left-sided colon, and 90 rectum. Forty-two patients (16.7%) had poorly differentiated or mucinous carcinoma. Among the 255 patients, 39 (15.3%) exhibited c-MET overexpression. There was no significant difference in the prevalence of c-MET overexpression according to primary site, histologic differentiation, molecular markers, or metastatic sites. In a comparison of the tumor response to first-line chemotherapy according to the level of c-MET expression, we found no significant difference in either partial response or disease control rate. In the survival analysis, patients with c-MET overexpression had significantly shorter overall survival (39 vs. 27 months; P = .018) and progression-free survival (PFS) during bevacizumab treatment (10 vs. 7 months; P = .024). c-MET overexpression, which was detected in 39 CRC patients (15.3%) irrespective of primary sites or molecular markers, indicated a poor survival prognosis and predicted shorter PFS during bevacizumab treatment in patients with CRC. Further studies are warranted to elucidate the value of c-MET-targeted therapy in CRC patients. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Role of cMET in the Development and Progression of Colorectal Cancer

Directory of Open Access Journals (Sweden)

Ilaria Bossi

2013-09-01

Full Text Available Mesenchymal-epithelial transition (MET is a member of a distinct subfamily of heterodimeric receptor tyrosine kinase receptors that specifically binds the hepatocyte growth factor (HGF. Binding to HGF leads to receptor dimerization/multimerization and phosphorylation, resulting in its catalytic activation. MET activation drives the malignant progression of several tumor types, including colorectal cancer (CRC, by promoting signaling cascades that mainly result in alterations of cell motility, survival, and proliferation. MET is aberrantly activated in many human cancers through various mechanisms, including point mutations, gene amplification, transcriptional up-regulation, or ligand autocrine loops. MET promotes cell scattering, invasion, and protection from apoptosis, thereby acting as an adjuvant pro-metastatic gene for many tumor types. In CRC, MET expression confers more aggressiveness and worse clinical prognosis. With all of this rationale, inhibitors that target the HGF/MET axis with different types of response have been developed. HGF and MET are new promising targets to understand the pathogenesis of CRC and for the development of new, targeted therapies.

Fosfaatwerking ogranische meststoffen vergelijkbaar met kunstmest

NARCIS (Netherlands)

Ehlert, P.A.I.; Pasterkamp, H.P.

2000-01-01

Gegevens in bijgaande tabel: Indicatieve fosfaatgehalten en de relatieve verdeling over mineraalfosfaat en organisch gebonden fosfaat in meststoffen met per mestsoort gegevens over het totaal fosfaatgehalte, het percentage mineraal fosfaat en het percentage organisch fosfaat

User-Defined Meteorological (MET) Profiles from Climatological and Extreme Condition Data

Science.gov (United States)

2018-04-01

ARL-TN-0876 ● MAR 2018 US Army Research Laboratory User-Defined Meteorological (MET) Profiles from Climatological and Extreme...needed. Do not return it to the originator. ARL-TN-0876 ● MAR 2018 US Army Research Laboratory User-Defined Meteorological (MET...User-Defined Meteorological (MET) Profiles from Climatological and Extreme Condition Data 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM

Rocket experiment METS - Microwave Energy Transmission in Space

Science.gov (United States)

Kaya, N.; Matsumoto, H.; Akiba, R.

A Microwave Energy Transmission in Space (METS) rocket experiment is being planned by the Solar Power Satellite Working Group at the Institute of Space and Astronautical Science in Japan for the forthcoming International Space Year, 1992. The METS experiment is an advanced version of the previous MINIX rocket experiment (Matsumoto et al., 1990). This paper describes a conceptual design of the METS rocket experiment. It aims at verifying a newly developed microwave energy transmission system for space use and to study nonlinear effects of the microwave energy beam in the space plasma environment. A high power microwave of 936 W will be transmitted by the new phased-array antenna from a mother rocket to a separated target (daughter rocket) through the ionospheric plasma. The active phased-array system has a capability of focusing the microwave energy around any spatial point by controlling the digital phase shifters individually.

Rocket experiment METS Microwave Energy Transmission in Space

Science.gov (United States)

Kaya, N.; Matsumoto, H.; Akiba, R.

A METS (Microwave Energy Transmission in Space) rocket experiment is being planned by the SPS (Solar Power Satellite) Working Group at the Institute of Space and Astronautical Science (ISAS) in Japan for the forthcoming International Space Year (ISY), 1992. The METS experiment is an advanced version of our MINIX rocket experiment. This paper describes the conceptual design for the METS rocket experiment. Aims are to verify the feasibility of a newly developed microwave energy transmission system designed for use in space and to study nonlinear effects of the microwave energy beam on space plasma. A high power microwave (936 W) will be transmitted by a new phase-array antenna from a mother rocket to a separate target (daughter rocket) through the Earth's ionospheric plasma. The active phased-array system has the capability of being able to focus the microwave energy at any spatial point by individually controlling the digital phase shifters.

{sup 11}C-MET PET/MRI for detection of recurrent glioma

Energy Technology Data Exchange (ETDEWEB)

Deuschl, C. [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); Kirchner, J.; Schaarschmidt, B. [University Duesseldorf, Department of Diagnostic and Interventional Radiology, Medical Faculty, Duesseldorf (Germany); Poeppel, T.D.; Herrmann, K. [University Hospital Essen, Clinic for Nuclear Medicine, Essen (Germany); Kebir, S.; Glas, M. [University Hospital Essen, Division of Clinical Neurooncology, Department of Neurology, Essen (Germany); El Hindy, N. [University Hospital Essen, Department of Neurosurgery, Essen (Germany); Hense, J. [University Hospital Essen, Department of Medical Oncology, West German Cancer Center, Essen (Germany); Quick, H.H. [University of Duisburg-Essen, Erwin L. Hahn Institute for Magnetic Resonance Imaging, Essen (Germany); University Hospital Essen, High Field and Hybrid MR Imaging, Essen (Germany); Umutlu, L.; Moenninghoff, C.; Radbruch, A.; Forsting, M. [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Schlamann, M. [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); University Hospital Cologne, Department of Diagnostic and Interventional Radiology, Cologne (Germany)

2018-04-15

Radiological assessment of brain tumors is widely based on the Radiology Assessment of Neuro-Oncology (RANO) criteria that consider non-specific T1 and T2 weighted images. Limitation of the RANO criteria is that they do not include metabolic imaging techniques that have been reported to be helpful to differentiate treatment related changes from true tumor progression. In the current study, we assessed if the combined use of MRI and PET with hybrid {sup 11}C-MET PET/MRI can improve diagnostic accuracy and diagnostic confidence of the readers to differentiate treatment related changes from true progression in recurrent glioma. Fifty consecutive patients with histopathologically proven glioma were prospectively enrolled for a hybrid {sup 11}C-MET PET/MRI to differentiate recurrent glioma from treatment induced changes. Sole MRI data were analyzed based on RANO. Sole PET data and in a third evaluation hybrid {sup 11}C-MET-PET/MRI data were assessed for metabolic respectively metabolic and morphologic glioma recurrence. Diagnostic performance and diagnostic confidence of the reader were calculated for the different modalities, and the McNemar test and Mann-Whitney U Test were applied for statistical analysis. Hybrid {sup 11}C-MET PET/MRI was successfully performed in all 50 patients. Glioma recurrence was diagnosed in 35 of the 50 patients (70%). Sensitivity and specificity were calculated for MRI (86.11% and 71.43%), for {sup 11}C-MET PET (96.77% and 73.68%), and for hybrid {sup 11}C-MET-PET/MRI (97.14% and 93.33%). For diagnostic accuracy hybrid {sup 11}C-MET-PET/MRI (96%) showed significantly higher values than MRI alone (82%), whereas no significant difference was found for 11C-MET PET (88%). Furthermore, by rating on a five-point Likert scale significantly higher scores were found for diagnostic confidence when comparing {sup 11}C-MET PET/MRI (4.26 ± 0,777) to either PET alone (3.44 ± 0.705) or MRI alone (3.56 ± 0.733). This feasibility study showed that hybrid

'Epistemology models ontology'− In gesprek met John Polkinghorne

African Journals Online (AJOL)

Test

7 Jun 2011 ... maar met die aard daarvan. Polkinghorne wil met sy boek One World (1996) presies sê wat die titel suggereer. Hiervoor kry hy die oplossing by sy mentor en latere kollega, Paul Dirac. Vir meer as 30 jaar het Dirac dieselfde leerstoel in Fisika aan Cambridge beklee as Isaac Newton (Polkinghorne 2005:34).

The applications of 11C-MET PET in brain tumor

International Nuclear Information System (INIS)

Hua Fengchun

2002-01-01

11 C-methionine (MET), an amino acid, is the most widely used radio pharmaceutics which can reflect transport metabolism of amino acid in vivo, and synthesis of protein in tumor. 11 C-MET PET can be used for evaluation of brain tumor: detection of tumor, differential diagnosis between recurrence and radiation necrosis and early evaluation of response to treatment. Especially, for the definition of tumor margin and detection of low-grade tumors, PET with 11 C-MET is better than PET with 18 F-FDG or other modalities such as CT and MRI

La variable latente calidad medida a través del modelo de Rasch.

Directory of Open Access Journals (Sweden)

Guerrero, Mª M.

1997-01-01

Full Text Available La obtención de aceites de oliva de calidad requiere unos cuidados especiales en todas y cada una de las sucesivas fases de elaboración de los mismos, es una cadena que comienza en el olivo y termina en el consumo. Condición indispensable para ello es conocer las características organolépticas del aceite (a fin de potenciar sus atributos y eliminar, en la medida de los posible, sus defectos, y la influencia del proceso de elaboración en las mismas. El control y medida de estos caracteres se hará mediante las catas, realizadas por expertos catadores utilizando para ello las fichas de cata del Consejo Oleícola Internacional. El modelo de Rasch, que emplearemos para obtener la evaluación sensorial de los aceites de oliva virgen, nos permitirá no sólo dar una calificación organoléptica global al aceite (que ya podemos realizar sin necesidad de aplicar ningún método, siguiendo la metodología de valoración del Consejo Oleícola Internacional, sino también clasificar y medir los factores sensoriales que intervienen en la calidad, lo que nos permitirá realizar las acciones oportunas encaminadas a obtener aceites de oliva de cualidades óptimas.

Milde voedselverwerkingstechnologie II : milde conservering met hoge druk : nieuwe ontwikkelingen

NARCIS (Netherlands)

Matser, A.M.; Ven, van der C.; Berg, van den R.

2004-01-01

Met behulp van hogedruktechnologie kunnen producten langer houdbaar worden gemaakt. Deze bekende techniek kent de laatste tijd nieuwe ontwikkelingen en toepassingen . Naast pasteuriseren door een hogedrukbehandeling bij kamertemperatuur is het nu ook mogelijk om te steriliseren met hoge druk. Ook

Bio-composiet : Thermoplastische kunsstof met natuurvezels

NARCIS (Netherlands)

Beurden, van K.M.M. (Karin); Goselink, E.A. (Erik)

2013-01-01

Een biocomposiet wordt samengesteld uit een vezel en een hars. In dit document worden twee verwerkingsvormen van biocomposieten behandeld: - Vezel/poeder versterkt kunststof (granulaat); - Kunststof plaatmateriaal versterkt met een weefsel (laminaat), ook wel Sizopreg® genoemd. Door een

Technisch lego met een Duplo-interface

NARCIS (Netherlands)

Pimentel, A.; Schipper, D.

2008-01-01

Daedalus is een ontwerpflow op systeemniveau waarmee techneuten snel kunnen experimenteren met verschillende multiprocessorarchitecturen tijdens de vroege stadia van het ontwerptraject. Het is het resultaat van tien jaar onderzoek en ontwikkeling binnen de Progress-projecten Artemis en Artemisia.

MET and Small-Cell Lung Cancer

Directory of Open Access Journals (Sweden)

Francesco Gelsomino

2014-10-01

Full Text Available Small-cell lung cancer (SCLC is one of the most aggressive lung tumors. The majority of patients with SCLC are diagnosed at an advanced stage. This tumor type is highly sensitive to chemo-radiation treatment, with very high response rates, but invariably relapses. At this time, treatment options are still limited and the prognosis of these patients is poor. A better knowledge of the molecular biology of SCLC allowed us to identify potential druggable targets. Among these, the MET/HGF axis seems to be one of the most aberrant signaling pathways involved in SCLC invasiveness and progression. In this review, we describe briefly all recent literature on the different molecular profiling in SCLC; in particular, we discuss the specific alterations involving c-MET gene and their implications as a potential target in SCLC.

Cooperative interaction of MUC1 with the HGF/c-Met pathway during hepatocarcinogenesis.

Science.gov (United States)

Bozkaya, Giray; Korhan, Peyda; Cokaklı, Murat; Erdal, Esra; Sağol, Ozgül; Karademir, Sedat; Korch, Christopher; Atabey, Neşe

2012-09-11

Hepatocyte growth factor (HGF) induced c-Met activation is known as the main stimulus for hepatocyte proliferation and is essential for liver development and regeneration. Activation of HGF/c-Met signaling has been correlated with aggressive phenotype and poor prognosis in hepatocellular carcinoma (HCC). MUC1 is a transmembrane mucin, whose over-expression is reported in most cancers. Many of the oncogenic effects of MUC1 are believed to occur through the interaction of MUC1 with signaling molecules. To clarify the role of MUC1 in HGF/c-Met signaling, we determined whether MUC1 and c-Met interact cooperatively and what their role(s) is in hepatocarcinogenesis. MUC1 and c-Met over-expression levels were determined in highly motile and invasive, mesenchymal-like HCC cell lines, and in serial sections of cirrhotic and HCC tissues, and these levels were compared to those in normal liver tissues. Co-expression of both c-Met and MUC1 was found to be associated with the differentiation status of HCC. We further demonstrated an interaction between c-Met and MUC1 in HCC cells. HGF-induced c-Met phosphorylation decreased this interaction, and down-regulated MUC1 expression. Inhibition of c-Met activation restored HGF-mediated MUC1 down-regulation, and decreased the migratory and invasive abilities of HCC cells via inhibition of β-catenin activation and c-Myc expression. In contrast, siRNA silencing of MUC1 increased HGF-induced c-Met activation and HGF-induced cell motility and invasion. These findings indicate that the crosstalk between MUC1 and c-Met in HCC could provide an advantage for invasion to HCC cells through the β-catenin/c-Myc pathway. Thus, MUC1 and c-Met could serve as potential therapeutic targets in HCC.

c-MET receptor tyrosine kinase as a molecular target in advanced hepatocellular carcinoma

Directory of Open Access Journals (Sweden)

Granito A

2015-04-01

Full Text Available Alessandro Granito,1 Elena Guidetti,1 Laura Gramantieri2,3 1Dipartimento di Scienze Mediche e Chirurgiche Università di Bologna, Bologna, Italy; 2Dipartimento dell'Apparato Digerente, Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy; 3Centro di Ricerca Biomedica Applicata (CRBA, Azienda Ospedaliero-Universitaria Policlinico S Orsola-Malpighi e Università di Bologna, Bologna, Italy Abstract: c-MET is the membrane receptor for hepatocyte growth factor (HGF, also known as scatter factor or tumor cytotoxic factor, a mitogenic growth factor for hepatocytes. HGF is mainly produced by cells of mesenchymal origin and it mainly acts on neighboring epidermal and endothelial cells, regulating epithelial growth and morphogenesis. HGF/MET signaling has been identified among the drivers of tumorigenesis in human cancers. As such, c-MET is a recognized druggable target, and against it, targeted agents are currently under clinical investigation. c-MET overexpression is a common event in a wide range of human malignancies, including gastric, lung, breast, ovary, colon, kidney, thyroid, and liver carcinomas. Despite c-MET overexpression being reported by a large majority of studies, no evidence for a c-MET oncogenic addiction exists in hepatocellular carcinoma (HCC. In particular, c-MET amplification is a rare event, accounting for 4%–5% of cases while no mutation has been identified in c-MET oncogene in HCC. Thus, the selection of patient subgroups more likely to benefit from c-MET inhibition is challenging. Notwithstanding, c-MET overexpression was reported to be associated with increased metastatic potential and poor prognosis in patients with HCC, providing a rationale for its therapeutic inhibition. Here we summarize the role of activated HGF/MET signaling in HCC, its prognostic relevance, and the implications for therapeutic approaches in HCC. Keywords: hepatocellular carcinoma, c-MET, clinical trials

Cooperative interaction of MUC1 with the HGF/c-Met pathway during hepatocarcinogenesis

Directory of Open Access Journals (Sweden)

Bozkaya Giray

2012-09-01

Full Text Available Abstract Background Hepatocyte growth factor (HGF induced c-Met activation is known as the main stimulus for hepatocyte proliferation and is essential for liver development and regeneration. Activation of HGF/c-Met signaling has been correlated with aggressive phenotype and poor prognosis in hepatocellular carcinoma (HCC. MUC1 is a transmembrane mucin, whose over-expression is reported in most cancers. Many of the oncogenic effects of MUC1 are believed to occur through the interaction of MUC1 with signaling molecules. To clarify the role of MUC1 in HGF/c-Met signaling, we determined whether MUC1 and c-Met interact cooperatively and what their role(s is in hepatocarcinogenesis. Results MUC1 and c-Met over-expression levels were determined in highly motile and invasive, mesenchymal-like HCC cell lines, and in serial sections of cirrhotic and HCC tissues, and these levels were compared to those in normal liver tissues. Co-expression of both c-Met and MUC1 was found to be associated with the differentiation status of HCC. We further demonstrated an interaction between c-Met and MUC1 in HCC cells. HGF-induced c-Met phosphorylation decreased this interaction, and down-regulated MUC1 expression. Inhibition of c-Met activation restored HGF-mediated MUC1 down-regulation, and decreased the migratory and invasive abilities of HCC cells via inhibition of β-catenin activation and c-Myc expression. In contrast, siRNA silencing of MUC1 increased HGF-induced c-Met activation and HGF-induced cell motility and invasion. Conclusions These findings indicate that the crosstalk between MUC1 and c-Met in HCC could provide an advantage for invasion to HCC cells through the β-catenin/c-Myc pathway. Thus, MUC1 and c-Met could serve as potential therapeutic targets in HCC.

Extraboard performance : TriMet case study.

Science.gov (United States)

2012-02-01

This paper examines extraboard operations and management at TriMet, the transit provider for the Portland Oregon metropolitan area. The : extraboard consists of a pool of operators who fill open work resulting from absences and other causes. The pape...

Preproghrelin Leu72Met polymorphism is not associated with type 2 diabetes mellitus.

Science.gov (United States)

Kim, Sun-Young; Jo, Dae-Sun; Hwang, Pyoung Han; Park, Ji Hyun; Park, Sung Kwang; Yi, Ho Keun; Lee, Dae-Yeol

2006-03-01

Ghrelin is a novel gut-brain peptide, which exerts somatotropic, orexigenic, and adipogenic effects. Genetic variants of ghrelin have been associated with both obesity and insulin metabolism. In this study, we determined a role of preproghrelin Leu72Met polymorphism on type 2 diabetes mellitus and its relationship to variables studied. Genotypes were assessed by polymerase chain reaction. Frequencies of the Leu72Met polymorphism were found to be 35.4% in the type 2 diabetic patients and 32.5% in the normal controls. The Leu72Met polymorphism was not associated with hypertension, macroangiopathy, retinopathy, serum cholesterol, triglyceride, blood urea nitrogen, HbA(1c), lipoprotein (a), fasting insulin, or 24-hour urinary protein levels in the type 2 diabetic group. However, the Leu72Met polymorphism was clearly associated with serum creatinine levels in the diabetic group, as the Met72 carriers exhibited lower serum creatinine levels than the Met72 noncarriers. Our data indicate that the preproghrelin Leu72Met polymorphism is not associated with type 2 diabetes mellitus. However, the Leu72Met polymorphism is associated with serum creatinine levels. These data suggest that Met72 carrier status may be a predictable marker for diabetic nephropathy or renal impairment in type 2 diabetes mellitus.

c-Met in esophageal squamous cell carcinoma: an independent prognostic factor and potential therapeutic target.

Science.gov (United States)

Ozawa, Yohei; Nakamura, Yasuhiro; Fujishima, Fumiyoshi; Felizola, Saulo J A; Takeda, Kenichiro; Okamoto, Hiroshi; Ito, Ken; Ishida, Hirotaka; Konno, Takuro; Kamei, Takashi; Miyata, Go; Ohuchi, Noriaki; Sasano, Hironobu

2015-06-03

c-Met is widely known as a poor prognostic factor in various human malignancies. Previous studies have suggested the involvement of c-Met and/or its ligand, hepatocyte growth factor (HGF), in esophageal squamous cell carcinoma (ESCC), but the correlation between c-Met status and clinical outcome remains unclear. Furthermore, the identification of a novel molecular therapeutic target might potentially help improve the clinical outcome of ESCC patients. The expression of c-Met and HGF was immunohistochemically assessed in 104 surgically obtained tissue specimens. The correlation between c-Met/HGF expression and patients' clinicopathological features, including survival, was evaluated. We also investigated changes in cell functions and protein expression of c-Met and its downstream signaling pathway components under treatments with HGF and/or c-Met inhibitor in ESCC cell lines. Elevated expression of c-Met was significantly correlated with tumor depth and pathological stage. Patients with high c-Met expression had significantly worse survival. In addition, multivariate analysis identified the high expression of c-Met as an independent prognostic factor. Treatment with c-Met inhibitor under HGF stimulation significantly inhibited the invasive capacity of an ESCC cell line with elevated c-Met mRNA expression. Moreover, c-Met and its downstream signaling inactivation was also detected after treatment with c-Met inhibitor. The results of our study identified c-Met expression as an independent prognostic factor in ESCC patients and demonstrated that c-Met could be a potential molecular therapeutic target for the treatment of ESCC with elevated c-Met expression.

A brief report on mets system

Digital Repository Service at National Institute of Oceanography (India)

Fernandes, W.A.

Mets system is basically a gas monitoring system, used for the detection of underwater gas. The system consists of a sensor, datalogger and energy module. The sensor works on the diffusion techniques. The system can be deployed to a water depth...

The potential roles of hepatocyte growth factor (HGF-MET pathway inhibitors in cancer treatment

Directory of Open Access Journals (Sweden)

Parikh RA

2014-06-01

Full Text Available Rahul A Parikh,1 Peng Wang,2 Jan H Beumer,3 Edward Chu,1 Leonard J Appleman11Division of Hematology-Oncology, University of Pittsburgh School of Medicine, Cancer Therapeutics Program, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA; 2Division of Medical Oncology, University of Kentucky College of Medicine, Markey Cancer Center, Lexington, KY, USA; 3University of Pittsburgh School of Pharmacy, Cancer Therapeutics Program, University of Pittsburgh Cancer Institute, Pittsburgh, PA, USAAbstract: MET is located on chromosome 7q31 and is a proto-oncogene that encodes for hepatocyte growth factor (HGF receptor, a member of the receptor tyrosine kinase (RTK family. HGF, also known as scatter factor (SF, is the only known ligand for MET. MET is a master regulator of cell growth and division (mitogenesis, mobility (motogenesis, and differentiation (morphogenesis; it plays an important role in normal development and tissue regeneration. The HGF-MET axis is frequently dysregulated in cancer by MET gene amplification, translocation, and mutation, or by MET or HGF protein overexpression. MET dysregulation is associated with an increased propensity for metastatic disease and poor overall prognosis across multiple tumor types. Targeting the dysregulated HGF-MET pathway is an area of active research; a number of monoclonal antibodies to HGF and MET, as well as small molecule inhibitors of MET, are under development. This review summarizes the key biological features of the HGF-MET axis, its dysregulation in cancer, and the therapeutic agents targeting the HGF-MET axis, which are in development.Keywords: MET inhibitor, HGF inhibitor, cancer

75 FR 1007 - MetLife, Inc. and MetLife Capital Trust V; Notice of Application

Science.gov (United States)

2010-01-07

... the definition of investment company by section 3(b) of the Act or by the rules or regulations under... Act for an exclusion from the definition of an investment company. To the extent MetLife or another... definition of a ``parent company'' in rule 3a-5(b)(2)(i) solely because it is an ``insurance company'' or...

Brain-derived neurotrophic factor Val66Met genotype modulates amygdala habituation.

Science.gov (United States)

Perez-Rodriguez, M Mercedes; New, Antonia S; Goldstein, Kim E; Rosell, Daniel; Yuan, Qiaoping; Zhou, Zhifeng; Hodgkinson, Colin; Goldman, David; Siever, Larry J; Hazlett, Erin A

2017-05-30

A deficit in amygdala habituation to repeated emotional stimuli may be an endophenotype of disorders characterized by emotion dysregulation, such as borderline personality disorder (BPD). Amygdala reactivity to emotional stimuli is genetically modulated by brain-derived neurotrophic factor (BDNF) variants. Whether amygdala habituation itself is also modulated by BDNF genotypes remains unknown. We used imaging-genetics to examine the effect of BDNF Val66Met genotypes on amygdala habituation to repeated emotional stimuli. We used functional magnetic resonance imaging (fMRI) in 57 subjects (19 BPD patients, 18 patients with schizotypal personality disorder [SPD] and 20 healthy controls [HC]) during a task involving viewing of unpleasant, neutral, and pleasant pictures, each presented twice to measure habituation. Amygdala responses across genotypes (Val66Met SNP Met allele-carriers vs. Non-Met carriers) and diagnoses (HC, BPD, SPD) were examined with ANOVA. The BDNF 66Met allele was significantly associated with a deficit in amygdala habituation, particularly for emotional pictures. The association of the 66Met allele with a deficit in habituation to unpleasant emotional pictures remained significant in the subsample of BPD patients. Using imaging-genetics, we found preliminary evidence that deficient amygdala habituation may be modulated by BDNF genotype. Copyright © 2017. Published by Elsevier B.V.

Catechol-O-Methyltransferase (COMT) Gene (Val158Met) and Brain-Derived Neurotropic Factor (BDNF) (Val66Met) Genes Polymorphism in Schizophrenia: A Case-Control Study.

Science.gov (United States)

Saravani, Ramin; Galavi, Hamid Reza; Lotfian Sargazi, Marzieh

2017-10-01

Objective: Several studies have shown that some polymorphisms of genes encoding catechol-O-methyltransferase (COMT), the key enzyme in degrading dopamine, and norepinephrine and the human brain-derived neurotropic factor (BDNF), a nerve growth factor, are strong candidates for risk of schizophrenia (SCZ). In the present study, we aimed at examining the effects of COMT Val158Met (G>A) and BDNF Val66Met (G>A) polymorphisms on SCZ risk in a sample of Iranian population. Method: This case- control study included 92 SCZ patients and 92 healthy controls (HCs). Genotyping of both variants (COMT Val158Met (G>A) and BDNF Val66Met (G>A)) were conducted using Amplification Refractory Mutation System-Polymerase Chain Reaction (ARMS-PCR). Results: The findings revealed that the COMT Val158Met (G>A) polymorphism was not associated with the risk/protective of SCZ in all models (OR=0.630, 95%CI=0.299-1.326, P=0.224, GA vs. GG, OR=1.416, 95%CI=0.719-2.793, P=0.314, AA vs. GG, OR=1.00, 95%CI=0.56-1.79, P=1.00 GA+AA vs. GG, OR=1.667, 95%CI=0.885-3.125, P=0.11, AA vs. GG+GA, OR=1.247, 95%CI=0.825-1.885, P=0.343, A vs. G,). However, BDNF Val66Met (G>A) variant increased the risk of SCZ (OR = 2.008 95%CI = 1.008-4.00, P = 0.047, GA vs. GG, OR = 3.876 95%CI = 1.001-14.925, P = 0.049. AA vs. GG, OR = 2.272. 95%CI = 1.204-4.347, P = 0.011, GA+AA vs. GG, OR = 2.22 95%CI = 1.29-3.82. P = 0.005, A vs. G). Conclusion: The results did not support an association between COMT Val158Met (G>A) variant and risk/protective of SCZ. Moreover, it was found that BDNF Val66Met (G>A) polymorphism may increase the risk of SCZ development. Further studies and different ethnicities are recommended to confirm the findings.

c-Met in esophageal squamous cell carcinoma: an independent prognostic factor and potential therapeutic target

International Nuclear Information System (INIS)

Ozawa, Yohei; Nakamura, Yasuhiro; Fujishima, Fumiyoshi; Felizola, Saulo JA; Takeda, Kenichiro; Okamoto, Hiroshi; Ito, Ken; Ishida, Hirotaka; Konno, Takuro; Kamei, Takashi; Miyata, Go; Ohuchi, Noriaki; Sasano, Hironobu

2015-01-01

c-Met is widely known as a poor prognostic factor in various human malignancies. Previous studies have suggested the involvement of c-Met and/or its ligand, hepatocyte growth factor (HGF), in esophageal squamous cell carcinoma (ESCC), but the correlation between c-Met status and clinical outcome remains unclear. Furthermore, the identification of a novel molecular therapeutic target might potentially help improve the clinical outcome of ESCC patients. The expression of c-Met and HGF was immunohistochemically assessed in 104 surgically obtained tissue specimens. The correlation between c-Met/HGF expression and patients’ clinicopathological features, including survival, was evaluated. We also investigated changes in cell functions and protein expression of c-Met and its downstream signaling pathway components under treatments with HGF and/or c-Met inhibitor in ESCC cell lines. Elevated expression of c-Met was significantly correlated with tumor depth and pathological stage. Patients with high c-Met expression had significantly worse survival. In addition, multivariate analysis identified the high expression of c-Met as an independent prognostic factor. Treatment with c-Met inhibitor under HGF stimulation significantly inhibited the invasive capacity of an ESCC cell line with elevated c-Met mRNA expression. Moreover, c-Met and its downstream signaling inactivation was also detected after treatment with c-Met inhibitor. The results of our study identified c-Met expression as an independent prognostic factor in ESCC patients and demonstrated that c-Met could be a potential molecular therapeutic target for the treatment of ESCC with elevated c-Met expression. The online version of this article (doi:10.1186/s12885-015-1450-3) contains supplementary material, which is available to authorized users

Activating mutation in MET oncogene in familial colorectal cancer

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Schildkraut Joellen M

2011-10-01

Full Text Available Abstract Background In developed countries, the lifetime risk of developing colorectal cancer (CRC is 5%, and it is the second leading cause of death from cancer. The presence of family history is a well established risk factor with 25-35% of CRCs attributable to inherited and/or familial factors. The highly penetrant inherited colon cancer syndromes account for approximately 5%, leaving greater than 20% without clear genetic definition. Familial colorectal cancer has been linked to chromosome 7q31 by multiple affected relative pair studies. The MET proto-oncogene which resides in this chromosomal region is considered a candidate for genetic susceptibility. Methods MET exons were amplified by PCR from germline DNA of 148 affected sibling pairs with colorectal cancer. Amplicons with altered sequence were detected with high-resolution melt-curve analysis using a LightScanner (Idaho Technologies. Samples demonstrating alternative melt curves were sequenced. A TaqMan assay for the specific c.2975C >T change was used to confirm this mutation in a cohort of 299 colorectal cancer cases and to look for allelic amplification in tumors. Results Here we report a germline non-synonymous change in the MET proto-oncogene at amino acid position T992I (also reported as MET p.T1010I in 5.2% of a cohort of sibling pairs affected with CRC. This genetic variant was then confirmed in a second cohort of individuals diagnosed with CRC and having a first degree relative with CRC at prevalence of 4.1%. This mutation has been reported in cancer cells of multiple origins, including 2.5% of colon cancers, and in Conclusions Although the MET p.T992I genetic mutation is commonly found in somatic colorectal cancer tissues, this is the first report also implicating this MET genetic mutation as a germline inherited risk factor for familial colorectal cancer. Future studies on the cancer risks associated with this mutation and the prevalence in different at-risk populations will

Varroabestrijding met bijenbroed als mijtenval (2)

NARCIS (Netherlands)

Calis, J.; Beetsma, J.; Boot, W.J.; Eijnde, van den J.; Ruijter, de A.

1994-01-01

Bij deze bestrijdingsmethode worden belegde darreraten uit een moergoede veger overgehangen naar het moerloze en later broedloze hoofdvolk. Hier worden de mijten die zich op de bijen bevinden gevangen. Nadat de laatste darreraat uit een hoofdvolk is verwijderd, wordt het bijenvolk met Perizine

Groen proceswater: zuivering brouwerijprocesafvalwater met microalgen

NARCIS (Netherlands)

Dijk, van W.; Weide, van der R.Y.; Kroon, A.

2016-01-01

In 2012 is het project Groen Proceswater gestart. Hierin worden de mogelijkheden van zuivering van brouwerijprocesafvalwater met behulp van microalgen onderzocht. Dit is gedaan in een samenwerkingsverband van Heineken Nederland BV, Algae Food & Fuel en WUR-ACRRES. De resultaten behaald in 2012

Risicoanalyse voor buisleidingen met brandbare vloeistoffen

NARCIS (Netherlands)

van Vliet AAC; Laheij GMH; Wolting AG; CEV

2006-01-01

De minimale veiligheidsafstanden tussen buisleidingen met brandbare vloeistoffen en bebouwingen kunnen gelijk blijven of iets verkleind worden. Dit is de conclusie na een herberekening van de afstanden uit een circulaire uit 1991. In Nederland ligt zo'n 1850 kilometer aan ondergrondse buisleiding

Rasch Validation of a Measure of Reform-Oriented Science Teaching Practices

Science.gov (United States)

You, Hye Sun

2016-06-01

Growing evidence from recent curriculum documents and previous research suggests that reform-oriented science teaching practices promote students' conceptual understanding, levels of achievement, and motivation to learn, especially when students are actively engaged in constructing their ideas through scientific inquiries. However, it is difficult to identify to what extent science teachers engage students in reform-oriented teaching practices (RTPs) in their science classrooms. In order to exactly diagnose the current status of science teachers' implementation of the RTPs, a valid and reliable instrument tool is needed. The principles of validity and reliability are fundamental cornerstones in developing a robust measurement tool. As such, this study was motivated by the desire to point out the limitations of the existing statistical and psychometric analyses and to further examine the validation of the RTP survey instrument. This paper thus aims at calibrating the items of the RTPs for science teachers using the Rasch model. The survey instrument scale was adapted from the 2012 National Survey of Science and Mathematics Education (NSSME) data. A total of 3701 science teachers from 1403 schools from across the USA participated in the NSSME survey. After calibrating the RTP items and persons on the same scale, the RTP instrument well represented the population of US science teachers. Model-data fit determined by Infit and Outfit statistics was within an appropriate range (0.5-1.5), supporting the unidimensional structure of the RTPs. The ordered category thresholds and the probability of the thresholds showed that the five-point rating scale functioned well. The results of this study support the use of the RTP measure from the 2012 NSSME in assessing usage of RTPs.

El sexo de las metáforas

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Pérez Sedeño, Eulalia

2011-02-01

Full Text Available The hypothesis that states metaphors are structurally determinant in our social relations, routines, and experience has been accepted broadly in the last decades. Moreover, metaphors are to be found in many different levels of scientific practices, and have a diverse set of functions in science. Therefore, they impregnate all scientific enterprise. In this work we examine selected gender metaphors used in biology. We show metaphors are effective precisely because its effectiveness depends on shared social conventions, kinship relations and, authority that, by convention, is given to those that use them.

La tesis de que las metáforas estructuran gran parte de nuestras relaciones sociales y nuestra experiencia cotidiana ha sido ampliamente aceptada en las últimas décadas. En la ciencia, además, aparecen en muchos niveles y desempeñan diversas funciones, impregnando todo el quehacer científico. En este trabajo se examinan algunas metáforas de género usadas en biología. Se muestra que las metáforas eficaces lo son porque su efectividad depende de las convenciones sociales compartidas, los parecidos de familia ya vigentes y de la autoridad que, por convención, se otorga a quienes las usan.

Project VALOR: Trajectories of Change in PTSD in Combat-Exposed Veterans

Science.gov (United States)

2016-10-01

assault by acquaintance/ stranger (5.4%). For women, the most Table 1 Sample characteristics across the three studies. Study 1 Study 2 Study 3 n 2953...228; (g) total = 971, PTSD+ = 664, PTSD− = 307; (h) total = 971, PTSD+ = 664, PTSD− = 307. Using the higher BMI cut -point of 30 in the diagnostic...with MetS using this more stringent BMI criterion at both T1 and T2, per χ2 analysis. Using the higher BMI cut -point of 30 in the MetS criteria count

Single-molecule photobleaching reveals increased MET receptor dimerization upon ligand binding in intact cells

International Nuclear Information System (INIS)

Dietz, Marina S; Haße, Daniel; Ferraris, Davide M; Göhler, Antonia; Niemann, Hartmut H; Heilemann, Mike

2013-01-01

The human receptor tyrosine kinase MET and its ligand hepatocyte growth factor/scatter factor are essential during embryonic development and play an important role during cancer metastasis and tissue regeneration. In addition, it was found that MET is also relevant for infectious diseases and is the target of different bacteria, amongst them Listeria monocytogenes that induces bacterial uptake through the surface protein internalin B. Binding of ligand to the MET receptor is proposed to lead to receptor dimerization. However, it is also discussed whether preformed MET dimers exist on the cell membrane. To address these issues we used single-molecule fluorescence microscopy techniques. Our photobleaching experiments show that MET exists in dimers on the membrane of cells in the absence of ligand and that the proportion of MET dimers increases significantly upon ligand binding. Our results indicate that partially preformed MET dimers may play a role in ligand binding or MET signaling. The addition of the bacterial ligand internalin B leads to an increase of MET dimers which is in agreement with the model of ligand-induced dimerization of receptor tyrosine kinases.

MetAssimulo:Simulation of Realistic NMR Metabolic Profiles

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De Iorio Maria

2010-10-01

Full Text Available Abstract Background Probing the complex fusion of genetic and environmental interactions, metabolic profiling (or metabolomics/metabonomics, the study of small molecules involved in metabolic reactions, is a rapidly expanding 'omics' field. A major technique for capturing metabolite data is 1H-NMR spectroscopy and this yields highly complex profiles that require sophisticated statistical analysis methods. However, experimental data is difficult to control and expensive to obtain. Thus data simulation is a productive route to aid algorithm development. Results MetAssimulo is a MATLAB-based package that has been developed to simulate 1H-NMR spectra of complex mixtures such as metabolic profiles. Drawing data from a metabolite standard spectral database in conjunction with concentration information input by the user or constructed automatically from the Human Metabolome Database, MetAssimulo is able to create realistic metabolic profiles containing large numbers of metabolites with a range of user-defined properties. Current features include the simulation of two groups ('case' and 'control' specified by means and standard deviations of concentrations for each metabolite. The software enables addition of spectral noise with a realistic autocorrelation structure at user controllable levels. A crucial feature of the algorithm is its ability to simulate both intra- and inter-metabolite correlations, the analysis of which is fundamental to many techniques in the field. Further, MetAssimulo is able to simulate shifts in NMR peak positions that result from matrix effects such as pH differences which are often observed in metabolic NMR spectra and pose serious challenges for statistical algorithms. Conclusions No other software is currently able to simulate NMR metabolic profiles with such complexity and flexibility. This paper describes the algorithm behind MetAssimulo and demonstrates how it can be used to simulate realistic NMR metabolic profiles with

Structural Basis for Selective Small Molecule Kinase Inhibition of Activated c-Met

Energy Technology Data Exchange (ETDEWEB)

Rickert, Keith W.; Patel, Sangita B.; Allison, Timothy J.; Byrne, Noel J.; Darke, Paul L.; Ford, Rachael E.; Guerin, David J.; Hall, Dawn L.; Kornienko, Maria; Lu, Jun; Munshi, Sanjeev K.; Reid, John C.; Shipman, Jennifer M.; Stanton, Elizabeth F.; Wilson, Kevin J.; Young, Jonathon R.; Soisson, Stephen M.; Lumb, Kevin J. (Merck)

2012-03-15

The receptor tyrosine kinase c-Met is implicated in oncogenesis and is the target for several small molecule and biologic agents in clinical trials for the treatment of cancer. Binding of the hepatocyte growth factor to the cell surface receptor of c-Met induces activation via autophosphorylation of the kinase domain. Here we describe the structural basis of c-Met activation upon autophosphorylation and the selective small molecule inhibiton of autophosphorylated c-Met. MK-2461 is a potent c-Met inhibitor that is selective for the phosphorylated state of the enzyme. Compound 1 is an MK-2461 analog with a 20-fold enthalpy-driven preference for the autophosphorylated over unphosphorylated c-Met kinase domain. The crystal structure of the unbound kinase domain phosphorylated at Tyr-1234 and Tyr-1235 shows that activation loop phosphorylation leads to the ejection and disorder of the activation loop and rearrangement of helix {alpha}C and the G loop to generate a viable active site. Helix {alpha}C adopts a orientation different from that seen in activation loop mutants. The crystal structure of the complex formed by the autophosphorylated c-Met kinase domain and compound 1 reveals a significant induced fit conformational change of the G loop and ordering of the activation loop, explaining the selectivity of compound 1 for the autophosphorylated state. The results highlight the role of structural plasticity within the kinase domain in imparting the specificity of ligand binding and provide the framework for structure-guided design of activated c-Met inhibitors.

Association of Catechol-O-methyltransferase polymorphism Val158Met and mammographic density: A meta-analysis.

Science.gov (United States)

Kallionpää, Roope A; Uusitalo, Elina; Peltonen, Juha

2017-08-15

The Val158Met polymorphism in catechol-O-methyltransferase (COMT) enzyme reduces the methylation of catechol estrogens, which may affect mammographic density. High mammographic density is a known risk factor of breast cancer. Our aim was to perform meta-analysis of the effect of COMT Val158Met polymorphism on mammographic density. Original studies reporting data on mammographic density, stratified by the presence of COMT Val158Met polymorphism, were identified and combined using genetic models Met/Val vs. Val/Val, Met/Met vs. Val/Val, Val/Met+Met/Met vs. Val/Val (dominant model) and Met/Met vs. Val/Met+Val/Val (recessive model). Subgroup analyses by breast cancer status, menopausal status and use of hormone replacement therapy (HRT) were also performed. Eight studies were included in the meta-analysis. The overall effect in percent mammographic density was -1.41 (CI -2.86 to 0.05; P=0.06) in the recessive model. Exclusion of breast cancer patients increased the effect size to -1.93 (CI -3.49 to -0.37; P=0.02). The results suggested opposite effect of COMT Val158Met for postmenopausal users of HRT versus premenopausal women or postmenopausal non-users of HRT. COMT Val158Met polymorphism may be associated with mammographic density at least in healthy women. Menopausal status and HRT should be taken into account in future studies to avoid masking of the underlying effects. Copyright © 2017 Elsevier B.V. All rights reserved.

Betere en efficiëntere zorg met Lean Six Sigma

NARCIS (Netherlands)

Trip, A.; Jong, L.J.; Does, R.J.M.M.

2009-01-01

Zorgaanbieders moeten steeds meer met elkaar concurreren. De wetten van de markteconomie worden daarom meer en meer van toepassing in de zorgsector die dat tot voor kort helemaal niet gewend was. Dat vergt veranderingen, zowel in het besturen van deze organisaties, als in de omgang met patiënten en

Synthesis of Tc-99m labeled 1,2,3-triazole-4-yl c-met binding peptide as a potential c-met receptor kinase positive tumor imaging agent.

Science.gov (United States)

Kim, Eun-Mi; Joung, Min-Hee; Lee, Chang-Moon; Jeong, Hwan-Jeong; Lim, Seok Tae; Sohn, Myung-Hee; Kim, Dong Wook

2010-07-15

The mesenchymal-epithelial transition factor (c-Met), which is related to tumor cell growth, angiogenesis and metastases, is known to be overexpressed in several tumor types. In this study, we synthesized technetium-99m labeled 1,2,3-triazole-4-yl c-Met binding peptide (cMBP) derivatives, prepared by solid phase peptide synthesis and the 'click-to-chelate' protocol for the introduction of tricarbonyl technetium-99m, as a potential c-Met receptor kinase positive tumor imaging agent, and evaluated their in vitro c-Met binding affinity, cellular uptake, and stability. The (99m)Tc labeled cMBP derivatives ([(99m)Tc(CO)(3)]12, [(99m)Tc(CO)(3)]13, and [(99m)Tc(CO)(3)]14) were prepared in 85-90% radiochemical yields. The cold surrogate cMBP derivatives, [Re(CO)(3)]12, [Re(CO)(3)]13, and [Re(CO)(3)]14, were shown to have high binding affinities (0.13 microM, 0.06 microM, and 0.16 microM, respectively) to a purified cMet/Fc chimeric recombinant protein. In addition, the in vitro cellular uptake and inhibition studies demonstrated the high specific binding of these (99m)Tc labeled cMBP derivatives ([(99m)Tc(CO)(3)]12-14) to c-Met receptor positive U87MG cells. 2010 Elsevier Ltd. All rights reserved.

Interview met Leon Deben: van tegenstellingen leer je het meeste

NARCIS (Netherlands)

van Diepen, A.; Huisman, C.

2008-01-01

Wat in de jaren zeventig begonnen is als Sociologie van bouwen en wonen is uitgegroeid tot Stadssociologie. Leon Deben heeft het medeopgebouwd. Hij nam onlangs afscheid van de universiteit met een rede over de openbare ruimte. "Het centrale bestuur van de stad is druk met de waan van de dag en dan

De betekenis van Paulus' oproep tot de groet met de heilige kus

NARCIS (Netherlands)

Voogd, Joanna Bernarda

Dit boek is een studie naar de betekenis van de Paulijnse oproep tot de groet met de heilige kus. In vier passages in het Nieuwe Testament is deze oproep vindbaar: “Groet alle broeders (en zusters) met de heilige kus” (1 Tes 5:26) of “groet elkaar met de heilige kus” (1 Kor 16:20; 2 Kor 13:12 en

The Met receptor tyrosine kinase prevents zebrafish primary motoneurons from expressing an incorrect neurotransmitter

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Eisen Judith S

2008-07-01

Full Text Available Abstract Background Expression of correct neurotransmitters is crucial for normal nervous system function. How neurotransmitter expression is regulated is not well-understood; however, previous studies provide evidence that both environmental signals and intrinsic differentiation programs are involved. One environmental signal known to regulate neurotransmitter expression in vertebrate motoneurons is Hepatocyte growth factor, which acts through the Met receptor tyrosine kinase and also affects other aspects of motoneuron differentiation, including axonal extension. Here we test the role of Met in development of motoneurons in embryonic zebrafish. Results We found that met is expressed in all early developing, individually identified primary motoneurons and in at least some later developing secondary motoneurons. We used morpholino antisense oligonucleotides to knock down Met function and found that Met has distinct roles in primary and secondary motoneurons. Most secondary motoneurons were absent from met morpholino-injected embryos, suggesting that Met is required for their formation. We used chemical inhibitors to test several downstream pathways activated by Met and found that secondary motoneuron development may depend on the p38 and/or Akt pathways. In contrast, primary motoneurons were present in met morpholino-injected embryos. However, a significant fraction of them had truncated axons. Surprisingly, some CaPs in met morpholino antisense oligonucleotide (MO-injected embryos developed a hybrid morphology in which they had both a peripheral axon innervating muscle and an interneuron-like axon within the spinal cord. In addition, in met MO-injected embryos primary motoneurons co-expressed mRNA encoding Choline acetyltransferase, the synthetic enzyme for their normal neurotransmitter, acetylcholine, and mRNA encoding Glutamate decarboxylase 1, the synthetic enzyme for GABA, a neurotransmitter never normally found in these motoneurons, but

Psychometric properties of the Oswestry disability index: Rasch analysis of responses in a work-disabled population.

Science.gov (United States)

Lochhead, Lois E; MacMillan, Peter D

2013-01-01

The Oswestry disability index (ODI) is the most widely used measure of perceived disability for low back conditions. It has been adopted without adaptation in functional capacity evaluation (FCE). Rigorous testing of the ODI with modern psychometric methods, in this setting, is warranted. To determine the psychometric properties of the ODI in FCE: unidimensionality; differential item functioning; item coverage and to identify poorly functioning items, allowing for improvement of these items and recalibration of the scale. Rasch analysis, specifically Masters' partial credit model, was conducted on data. 133 work-disabled individuals presenting for FCE in northern British Columbia, Canada. All items had one poorly functioning option. Items were rescaled from six categories to five, improving the psychometric properties of the ODI as a unidimensional (disability due to back pain) scale. Item difficulty range is sufficient for a population with mild to severe disability. Although two of the ten ODI items functioned marginally unsatisfactorily in the unrevised state, the 5-option revised ODI appears superior. Use in clinical settings across a broad spectrum of disability levels could help establish its psychometric properties. Health professionals should be aware that the ODI may perform differently depending on client population.

Voice: Reflections on an Artist-Led Program at the Met

Science.gov (United States)

Valladares, Maya

2017-01-01

This article explores an education project in which artist Fred Wilson, poets from Lincoln Center's Poet-Linc program, and the Met Museum Education Department collaborated to produce a teen-led spoken-word poetry performance in the Met's galleries. Wilson drew from his own knowledge of the collection to facilitate a group dialogue about objects…

Item-Level Psychometrics of the Glasgow Outcome Scale: Extended Structured Interviews.

Science.gov (United States)

Hong, Ickpyo; Li, Chih-Ying; Velozo, Craig A

2016-04-01

The Glasgow Outcome Scale-Extended (GOSE) structured interview captures critical components of activities and participation, including home, shopping, work, leisure, and family/friend relationships. Eighty-nine community dwelling adults with mild-moderate traumatic brain injury (TBI) were recruited (average = 2.7 year post injury). Nine items of the 19 items were used for the psychometrics analysis purpose. Factor analysis and item-level psychometrics were investigated using the Rasch partial-credit model. Although the principal components analysis of residuals suggests that a single measurement factor dominates the measure, the instrument did not meet the factor analysis criteria. Five items met the rating scale criteria. Eight items fit the Rasch model. The instrument demonstrated low person reliability (0.63), low person strata (2.07), and a slight ceiling effect. The GOSE demonstrated limitations in precisely measuring activities/participation for individuals after TBI. Future studies should examine the impact of the low precision of the GOSE on effect size. © The Author(s) 2016.

Validation of a Targeted Peer Relations Scale for Adolescents Treated for Substance Use Disorder: An Application of Rasch Modeling

Directory of Open Access Journals (Sweden)

James R. Ciesla

2011-01-01

Full Text Available The objective of this research is to use item response theory (IRT to validate a 14-item peer relations scale for use in the adolescent treatment population. Subjects are 509 adolescents discharged from substance abuse treatment from 2004–2009. The person reliability is 0.76 and the Cronbach's alpha person raw score reliability is 0.93 both indicating the scale is a strong metric. The item reliability of 0.99 is high showing the model is reliable. The real separation (8.49 meaning items are placed on the Rasch “ruler” with about eight levels of importance identified. The mean-square statistics of the infit and outfit values were between 0.5 and 1.5 for the items indicating a low level of randomness and thus unidimensionality of the scale. Inspection of a Wright Item Map shows the hierarchical structure of the scale with a moderate degree of inter-item spread. The analysis shows the scale is a reliable unidimensional metric.

Kas Eesti Mets on vanim praegu ilmuv eestikeelne ajakiri? / Rosmarii Kurvits

Index Scriptorium Estoniae

Kurvits, Roosmarii, 1969-

2015-01-01

Artiklist selgub, et vanim tänini ilmuv eestikeelne ajakiri on baptistide häälekandja Teekäija. Kuid vanuselt järgmine ongi 1921. aastast ilmuv Eesti Mets. Ühtlasi on Eesti Mets vanim kodumaine loodusajakiri

Exploring Variability Sources in Student Evaluation of Teaching via Many-Facet Rasch Model

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Bengü BÖRKAN

2017-03-01

Full Text Available Evaluating quality of teaching is important in nearly every higher education institute. The most common way of assessing teaching effectiveness takes place through students. Student Evaluation of Teaching (SET is used to gather information about students’ experiences with a course and instructor’s performance at some point of semester. SET can be considered as a type of rater mediated performance assessment where students are the raters and instructors are the examinees. When performance assessment becomes a rater mediated assessment process, extra measures need to be taken into consideration in order to create more reliable and fair assessment practices. The study has two main purposes; (a to examine the extent to which the facets (instructor, student, and rating items contribute to instructors’ score variance and (b to examine the students’ judging behavior in order to detect any potential source of bias in student evaluation of teaching by using the Many-Facet Rasch Model. The data set includes one thousand 235 students’ responses from 254 courses. The results show that a students greatly differ in the severity while rating instructors, b students were fairly consistent in their ratings, c students as a group and individual level are tend to display halo effect in their ratings, d students are clustered at the highest two categories of the scale and e the variation in item measures is fairly low. The findings have practical implications for the SET practices by improving the psychometric quality of measurement.

Activation of the JNK pathway is essential for transformation by the Met oncogene.

Science.gov (United States)

Rodrigues, G A; Park, M; Schlessinger, J

1997-05-15

The Met/Hepatocyte Growth Factor (HGF) receptor tyrosine kinase is oncogenically activated through a rearrangement that creates a hybrid gene Tpr-Met. The resultant chimeric p65(Tpr-Met) protein is constitutively phosphorylated on tyrosine residues in vivo and associates with a number of SH2-containing signaling molecules including the p85 subunit of PI-3 kinase and the Grb2 adaptor protein, which couples receptor tyrosine kinases to the Ras signaling pathway. Mutation of the binding site for Grb2 impairs the ability of Tpr-Met oncoprotein to transform fibroblasts, suggesting that the activation of the Ras/MAP kinase signaling pathway through Grb2 may be essential for cellular transformation. To test this hypothesis dominant-negative mutants of Grb2 with deletions of the SH3 domains were introduced into Tpr-Met transformed fibroblasts. Cells overexpressing the mutants were found to be morphologically reverted and exhibited reduced growth in soft agar. Surprisingly, the Grb2 mutants blocked activation of the JNK/SAPK but not MAP kinase activity induced by the Tpr-Met oncoprotein. Additionally, cells expressing dominant-negative Grb2 mutants had reduced PI-3-kinase activity and dominant-negative mutants of Rac1 blocked both Tpr-Met-induced transformation and activation of JNK. These experiments reveal a novel link between Met and the JNK pathway, which is essential for transformation by this oncogene.

Intern transport beter te plannen met computer

NARCIS (Netherlands)

Annevelink, E.

1999-01-01

Verbetering van intern transport in de potplantenteelt. Door getoetste vuistregels te combineren met toegepaste wiskunde is automatische planning van het intern transport binnen handbereik. Dit leidt tot minder transportbewegingen en tijdsbesparing bij het plannen

In vivo detection of c-Met expression in a rat C6 glioma model.

Science.gov (United States)

Towner, R A; Smith, N; Doblas, S; Tesiram, Y; Garteiser, P; Saunders, D; Cranford, R; Silasi-Mansat, R; Herlea, O; Ivanciu, L; Wu, D; Lupu, F

2008-01-01

The tyrosine kinase receptor, c-Met, and its substrate, the hepatocyte growth factor (HGF), are implicated in the malignant progression of glioblastomas. In vivo detection of c-Met expression may be helpful in the diagnosis of malignant tumours. The C6 rat glioma model is a widely used intracranial brain tumour model used to study gliomas experimentally. We used a magnetic resonance imaging (MRI) molecular targeting agent to specifically tag the cell surface receptor, c-Met, with an anti-c-Met antibody (Ab) linked to biotinylated Gd (gadolinium)-DTPA (diethylene triamine penta acetic acid)-albumin in rat gliomas to detect overexpression of this antigen in vivo. The anti-c-Met probe (anti-c-Met-Gd-DTPA-albumin) was administered intravenously, and as determined by an increase in MRI signal intensity and a corresponding decrease in regional T(1) relaxation values, this probe was found to detect increased expression of c-Met protein levels in C6 gliomas. In addition, specificity for the binding of the anti-c-Met contrast agent was determined by using fluorescence microscopic imaging of the biotinylated portion of the targeting agent within neoplastic and 'normal'brain tissues following in vivo administration of the anti-c-Met probe. Controls with no Ab or with a normal rat IgG attached to the contrast agent component indicated no non-specific binding to glioma tissue. This is the first successful visualization of in vivo overexpression of c-Met in gliomas.

Muziektherapie voor kinderen en jongeren met ASS : En overzicht van de relevante literatuur

NARCIS (Netherlands)

Pater, Mathieu; van Yperen, Tom

Muziektherapie wordt met grote regelmaat toegepast bij kinderen en jongeren met een autismespectrumstoornis (ASS). De vraag is of dit effect heeft. Dit artikel geeft een overzicht van de recente literatuur op dit vlak. Over de periode 1990 tot en met 2016 zijn 33 studies gevonden naar de inzet en

A comparison of Rasch item-fit and Cronbach's alpha item reduction analysis for the development of a Quality of Life scale for children and adolescents.

Science.gov (United States)

Erhart, M; Hagquist, C; Auquier, P; Rajmil, L; Power, M; Ravens-Sieberer, U

2010-07-01

This study compares item reduction analysis based on classical test theory (maximizing Cronbach's alpha - approach A), with analysis based on the Rasch Partial Credit Model item-fit (approach B), as applied to children and adolescents' health-related quality of life (HRQoL) items. The reliability and structural, cross-cultural and known-group validity of the measures were examined. Within the European KIDSCREEN project, 3019 children and adolescents (8-18 years) from seven European countries answered 19 HRQoL items of the Physical Well-being dimension of a preliminary KIDSCREEN instrument. The Cronbach's alpha and corrected item total correlation (approach A) were compared with infit mean squares and the Q-index item-fit derived according to a partial credit model (approach B). Cross-cultural differential item functioning (DIF ordinal logistic regression approach), structural validity (confirmatory factor analysis and residual correlation) and relative validity (RV) for socio-demographic and health-related factors were calculated for approaches (A) and (B). Approach (A) led to the retention of 13 items, compared with 11 items with approach (B). The item overlap was 69% for (A) and 78% for (B). The correlation coefficient of the summated ratings was 0.93. The Cronbach's alpha was similar for both versions [0.86 (A); 0.85 (B)]. Both approaches selected some items that are not strictly unidimensional and items displaying DIF. RV ratios favoured (A) with regard to socio-demographic aspects. Approach (B) was superior in RV with regard to health-related aspects. Both types of item reduction analysis should be accompanied by additional analyses. Neither of the two approaches was universally superior with regard to cultural, structural and known-group validity. However, the results support the usability of the Rasch method for developing new HRQoL measures for children and adolescents.

Doktora Yeterlikler Çerçevesinde Öğretim Üyesi, Akran ve Öz Değerlendirmelerin Rasch Ölçme Modeliyle Analizi

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Çetin SEMERCİ

2011-12-01

Full Text Available The aim of this study is to perform the analysis of faculty member, peer and self evaluation by applying Rasch model within the scope of doctorate competencies. In this study in which survey method was used, the faculty members and researchers were chosen entirely on a voluntary basis. The Rasch model has three levels. In the study, the levels comprise of 11 evaluators, 5 of whom are faculty members and 6 are postgraduate students specified in the jury , 15 competencies which are adopted by the Council of Higher Education and are criteria being currently developed and 6 postgraduate students evaulated. The study group is composed of 5 faculty members working in the division of Curriculum and Intruction as of May 2011 and 6 postgraduate students educated in this department in Fırat University. According to the study findings, within the framework of determined criteria, the ones giving an outstanding performance were P1 and P2. In other words, P1 and P2 coded students were decided to be more adequate and P5 and P6 coded students were less adequate than the others.It was confirmed that J5 was the most lenient and J4 was the severest ones among the juries carrying out the evaluation. The most difficult task was B3 (taking the lead in specific and interdisciplinary studies and the easiest task was I3 (using a language at least at C1 level taking part in The European Language Portfolio; the ability of written, oral or visual communucation at an advanced level and discussion. In this study, it was observed differences between the competencies of the postgraduate students.It is recommended that training programs for resolving these observed differences should be provided for instructors and postgraduate students

Beeldverwerking met de Micron Automatic Processor

OpenAIRE

Goyens, Frank

2017-01-01

Deze thesis is een onderzoek naar toepassingen binnen beeldverwerking op de Micron Automata Processor hardware. De hardware wordt vergeleken met populaire hedendaagse hardware. Ook bevat dit onderzoek nuttige informatie en strategieën voor het ontwikkelen van nieuwe toepassingen. Bevindingen in dit onderzoek omvatten proof of concept algoritmes en een praktische toepassing.

Remembering the early days of the Met Lab

International Nuclear Information System (INIS)

Katz, J.J.

1990-01-01

The Met Lab was set up by the war-time Manhattan District, US Corp of Engineers to (i) find a system using normal uranium in which a chain reaction would occur; (ii) to show that if such a chain reaction did occur, it would be possible to separate plutonium chemically from the uranium matrix and the fission products formed in the chain reactions; and (iii) to prepare plans for the large-scale production of plutonium. Chemistry Section C-1 of the Met Lab was assigned the responsibility for developing separation methods for plutonium production on the industrial scale. This report describes some aspects of daily life in Section C-1

Clinical and prognostic value of the C-Met/HGF signaling pathway in cervical cancer.

Science.gov (United States)

Boromand, Nadia; Hasanzadeh, Malihe; ShahidSales, Soodabeh; Farazestanian, Marjaneh; Gharib, Masoumeh; Fiuji, Hamid; Behboodi, Negin; Ghobadi, Niloofar; Hassanian, Seyed Mahdi; Ferns, Gordon A; Avan, Amir

2018-06-01

Aberrant activation of the HGF/c-Met signalling pathway is reported to be associated with cell proliferation, progression, and metastasis features of several tumor types, including cervical cancer, suggesting that it may be of potential value as a novel therapeutic target. Furthermore, HPV-positive patients had a higher serum level of HGF or c-Met protein, compared with HPV-negative patients. c-Met or HGF overexpression in lesions of cervical cancer is reported to be related to a poorer prognosis, and hence this may be of value as a prognostic and predictive biomarker. Several approaches have been developed for targeting HGF and/or c-Met. One of these is crizotinib (a dual c-Met/ALK inhibitor). This has been approved by FDA for the treatment of lung-cancer. Further investigations are required to evaluate and optimize the use of c-Met inhibitors in cervical cancer or parallel targeting signalling pathway associated/activated via MET/HGF pathway. The main aim of current review was to give an overview of the potential of the c-Met/HGF pathway as a prognostic, or predictive biomarker in cervical cancer. © 2017 Wiley Periodicals, Inc.

Anomalous inhibition of c-Met by the kinesin inhibitor aurintricarboxylic acid.

Science.gov (United States)

Milanovic, Mina; Radtke, Simone; Peel, Nick; Howell, Michael; Carrière, Virginie; Joffre, Carine; Kermorgant, Stéphanie; Parker, Peter J

2012-03-01

c-Met [the hepatocyte growth factor (HGF) receptor] is a receptor tyrosine kinase playing a role in various biological events. Overexpression of the receptor has been observed in a number of cancers, correlating with increased metastatic tendency and poor prognosis. Additionally, activating mutations in c-Met kinase domain have been reported in a subset of familial cancers causing resistance to treatment. Receptor trafficking, relying on the integrity of the microtubule network, plays an important role in activation of downstream targets and initiation of signalling events. Aurintricarboxylic acid (ATA) is a triphenylmethane derivative that has been reported to inhibit microtubule motor proteins kinesins. Additional reported properties of this inhibitor include inhibition of protein tyrosine phosphatases, nucleases and members of the Jak family. Here we demonstrate that ATA prevents HGF-induced c-Met phosphorylation, internalisation, subsequent receptor trafficking and degradation. In addition, ATA prevented HGF-induced downstream signalling which also affected cellular function, as assayed by collective cell migration of A549 cells. Surprisingly, the inhibitory effect of ATA on HGF-induced phosphorylation and signalling in vivo was associated with an increase in basal c-Met kinase activity in vitro. It is concluded that the inhibitory effects of ATA on c-Met in vivo is an allosteric effect mediated through the kinase domain of the receptor. As the currently tested adenosine triphosphate competitive tyrosine kinase inhibitors (TKIs) may lead to tumor resistance (McDermott U, et al., Cancer Res 2010;70:1625-34), our findings suggest that novel anti-c-Met therapies could be developed in the future for cancer treatment. Copyright © 2011 UICC.

Preproghrelin Leu72Met polymorphism in Chinese subjects with coronary artery disease and controls.

Science.gov (United States)

Tang, Na-Ping; Wang, Lian-Sheng; Yang, Li; Gu, Hai-Juan; Zhu, Huai-Jun; Zhou, Bo; Sun, Qing-Min; Cong, Ri-Hong; Wang, Bin

2008-01-01

Ghrelin, a novel endogenous ligand for the growth hormone secretagogue receptor, is considered to exert a protective effect against atherosclerosis. The Leu72Met (+408C>A) polymorphic variant of the preproghrelin, the gene for the ghrelin precursor, has been linked to obesity, diabetes and metabolic syndrome. However, it is unclear whether this polymorphism is associated with coronary artery disease (CAD). We conducted a case-control study with 317 CAD patients and 323 controls to investigate the potential association of the Leu72Met polymorphism with the occurrence of CAD and CAD-related phenotypes in Chinese population. No significant difference in the Leu72Met genotype frequency was observed between CAD patients and controls (P=NS). The Leu72Met polymorphism was not associated with hypertension, diabetes, dyslipidemia, the number of diseased vessels, plasma total cholesterol, triglyceride, high density lipoprotein cholesterol, low density lipoprotein cholesterol or fasting glucose levels in CAD patients. However, among CAD patients, those with variant genotypes (Leu72Met and Met72Met) had lower BMI (24.4+/-0.3 kg/m(2)) than Leu72Leu carriers (25.4+/-0.2 kg/m(2), adjusted P=0.033). Our data indicate that the preproghrelin Leu72Met polymorphism is not associated with CAD in Chinese population. However, the Leu72Met variant is associated with BMI among CAD patients.

Measuring Life Satisfaction in Parkinson's Disease and Healthy Controls Using the Satisfaction With Life Scale.

Science.gov (United States)

Løvereide, Lise; Hagell, Peter

2016-01-01

The 5-item Satisfaction With Life Scale (SWLS) was designed to measure general life satisfaction (LS). Here we examined the psychometric properties of the SWLS in a cohort of persons with Parkinson`s disease (PwPD) and age and gender matched individuals without PD. The SWLS was administered to PwPD and controls from the Norwegian ParkWest study at 5 and 7 years after the time of diagnosis. Data were analysed according to classical test theory (CTT) and Rasch measurement theory. CTT scaling assumptions for computation of a SWLS total score were met (corrected item-total correlations >0.58). The SWLS was reasonably well targeted to the sample and had good reliability (ordinal alpha, 0.92). The scale exhibited good fit to the Rasch model and successfully separated between 5 statistically distinct strata of people (levels of SWLS). The seven response categories did not work as intended and the scale may benefit from reduction to five response categories. There was no clinically significant differential item functioning. Separate analyses in PwPD and controls yielded very similar results to those from the pooled analysis. This study supports the SWLS as a valid instrument for measuring LS in PD and controls. However, Rasch analyses provided new insights into the performance and validity of the SWLS and identified areas for future revisions in order to further improve the scale.

Reciprocal activating crosstalk between c-Met and caveolin 1 promotes invasive phenotype in hepatocellular carcinoma.

Science.gov (United States)

Korhan, Peyda; Erdal, Esra; Kandemiş, Emine; Cokaklı, Murat; Nart, Deniz; Yılmaz, Funda; Can, Alp; Atabey, Neşe

2014-01-01

c-Met, the receptor for Hepatocyte Growth Factor (HGF), overexpressed and deregulated in Hepatocellular Carcinoma (HCC). Caveolin 1 (CAV1), a plasma membrane protein that modulates signal transduction molecules, is also overexpressed in HCC. The aim of this study was to investigate biological and clinical significance of co-expression and activation of c-Met and CAV1 in HCC. We showed that c-Met and CAV1 were co-localized in HCC cells and HGF treatment increased this association. HGF-triggered c-Met activation caused a concurrent rise in both phosphorylation and expression of CAV1. Ectopic expression of CAV1 accelerated c-Met signaling, resulted in enhanced migration, invasion, and branching-morphogenesis. Silencing of CAV1 downregulated c-Met signaling, and decreased migratory/invasive capability of cells and attenuated branching morphogenesis. In addition, activation and co-localization of c-Met and CAV1 were elevated during hepatocarcinogenesis. In conclusion reciprocal activating crosstalk between c-Met and CAV1 promoted oncogenic signaling of c-Met contributed to the initiation and progression of HCC.

Reciprocal activating crosstalk between c-Met and caveolin 1 promotes invasive phenotype in hepatocellular carcinoma.

Directory of Open Access Journals (Sweden)

Peyda Korhan

Full Text Available c-Met, the receptor for Hepatocyte Growth Factor (HGF, overexpressed and deregulated in Hepatocellular Carcinoma (HCC. Caveolin 1 (CAV1, a plasma membrane protein that modulates signal transduction molecules, is also overexpressed in HCC. The aim of this study was to investigate biological and clinical significance of co-expression and activation of c-Met and CAV1 in HCC. We showed that c-Met and CAV1 were co-localized in HCC cells and HGF treatment increased this association. HGF-triggered c-Met activation caused a concurrent rise in both phosphorylation and expression of CAV1. Ectopic expression of CAV1 accelerated c-Met signaling, resulted in enhanced migration, invasion, and branching-morphogenesis. Silencing of CAV1 downregulated c-Met signaling, and decreased migratory/invasive capability of cells and attenuated branching morphogenesis. In addition, activation and co-localization of c-Met and CAV1 were elevated during hepatocarcinogenesis. In conclusion reciprocal activating crosstalk between c-Met and CAV1 promoted oncogenic signaling of c-Met contributed to the initiation and progression of HCC.

Pepino overdraagbaar via zaad (interview met René van der Vlugt)

NARCIS (Netherlands)

Boonekamp, G.; Vlugt, van der R.A.A.

2008-01-01

Zaad geoogst van planten met pepinomozaïekvirus vormt een risico voor de overdracht van het virus naar teeltbedrijven. Dit blijkt uit resultaten van het Europees onderzoeksproject Pereira. Al langer bestonden er vermoedens dat pepino met zaad wordt overgebracht. Nu blijkt inderdaad dat het virus,

Variant BDNF Val66Met polymorphism affects extinction of conditioned aversive memory.

Science.gov (United States)

Yu, Hui; Wang, Yue; Pattwell, Siobhan; Jing, Deqiang; Liu, Ting; Zhang, Yun; Bath, Kevin G; Lee, Francis S; Chen, Zhe-Yu

2009-04-01

Brain-derived neurotrophic factor (BDNF) plays important roles in activity-dependent plasticity processes, such as long-term potentiation, learning, and memory. The recently reported human BDNF Val66Met (BDNF(Met)) polymorphism has been shown to lead to altered hippocampal volume and impaired hippocampal-dependent memory and is associated with a variety of neuropsychiatric disorders. There are few studies, however, that investigate the effect of the BDNF(Met) polymorphism on hippocampal-independent memory processes. A conditioned taste aversion (CTA) task was used for studying the mechanisms of long-term, hippocampal-independent, nondeclarative memory in the mammalian brain. Using the CTA paradigm, we found a novel impairment in extinction learning, but not acquisition or retention, of aversive memories resulting from the variant BDNF(Met). BDNF(Met) mice were slower to extinguish an aversive CTA memory compared with wild-type counterparts. Moreover, the BDNF(Met) was associated with smaller volume and decreased neuronal dendritic complexity in the ventromedial prefrontal cortex (vmPFC), which plays a significant role in extinction of CTA. Finally, this delay in extinction learning could be rescued pharmacologically with a cognitive enhancer, d-cycloserine (DCS). To our knowledge, this is the first evidence that the BDNF(Met) polymorphism contributes to abnormalities in memory extinction. This abnormality in extinction learning may be explained by alterations in neuronal morphology, as well as decreased neural activity in the vmPFC. Importantly, DCS was effective in rescuing this delay in extinction, suggesting that when coupled with behavior therapy, DCS may be an effective treatment option for anxiety disorders in humans with this genetic variant BDNF.

Gesloten kringloop met omgekeerde osmose of membraandestilatie

NARCIS (Netherlands)

Stijger, H.; Os, van E.A.

2011-01-01

TNO heeft samen met Wageningen UR Glastuinbouw een inventarisatie uitgevoerd naar geschikte zuiveringstechnieken om de waterstroom op tuinbouwbedrijven gesloten te krijgen. Uit de haalbaarheidstudie komen twee veelbelovende technieken naar voren die op vrij korte termijn inzetbaar zijn: omgekeerde

Metaphor and Corpus Linguistics Metáfora e linguística de corpus

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Tony Berber Sardinha

2011-01-01

Full Text Available In this paper, I look at four different aspects of metaphor research from a corpus linguistic perspective, namely: (1 the lexicogrammar of metaphors, which refers to the patterning of linguistic metaphor revealed by corpus analysis; (2 metaphor probabilities, which is a facet of metaphor that emerges from frequency-based studies of metaphor; (3 dimensions of metaphor variation, or the search for systematic parameters of variation in metaphor use across different registers; and (4 automated metaphor retrieval, which relates to the development of software to help identify metaphors in corpora. I argue that these four aspects are interrelated, and that advances in one of them can drive changes in the others.Neste artigo discuto quarto aspectos da pesquisa sobre metáfora do ponto de vista da linguística de corpus: (1 a lexicogramática das metáforas, que se refere aos padrões da metáfora linguística revelados pela análise de corpus; (2 probabilidades metafóricas, que é uma faceta da metáfora que emerge a partir dos estudos relacionados à freqüência de metáforas; (3 dimensões da variação de metáforas, ou a busca por parâmetros sistemáticos de variação de uso de metáfora em diferentes gêneros; e (4 captura automática de metáfora, que está relacionada ao desenvolvimento de softwares que auxiliam na identificação de metáforas em corpora. I defendo que esses quatro aspectos são interrelacionados, e que progressos em um deles podem acarretar mudanças nos outros.

Recurrent MET fusion genes represent a drug target in pediatric glioblastoma

DEFF Research Database (Denmark)

Sehested, Astrid Marie

2016-01-01

Pediatric glioblastoma is one of the most common and most deadly brain tumors in childhood. Using an integrative genetic analysis of 53 pediatric glioblastomas and five in vitro model systems, we identified previously unidentified gene fusions involving the MET oncogene in ∼10% of cases. These MET...

Met tyrosine kinase inhibitor, PF-2341066, suppresses growth and invasion of nasopharyngeal carcinoma

Directory of Open Access Journals (Sweden)

Zhao Y

2015-08-01

Full Text Available Yuanyuan Zhao,1,* Jing Zhang,2,* Ying Tian,1,* Cong Xue,1 Zhihuang Hu,1 Li Zhang1,3 1Department of Medical Oncology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, 2Department of Medical Oncology, the First Affiliated Hospital of Guang Zhou Traditional Chinese Medicine University, 3National Anti-Cancer Drug Research Centre, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, and Collaborative Innovation Center for Cancer Medicine, Guangzhou, People’s Republic of China*These authors contributed equally to this work Purpose: We explored the effect of hepatocyte growth factor (HGF/Met signaling pathway on nasopharyngeal carcinoma (NPC cells in vitro and in vivo, and investigated the ability of Met tyrosine kinase inhibitor (TKI to block HGF-induced biological signaling.Experimental design: Met TKI inhibitor PF-2341066 alone, or in combination with cisplatin, was investigated for its ability to block HGF-induced signaling and biological effects in vitro and in vivo. HGF/Met expression and activation of signaling in NPC cells were detected by using Western blot and immunohistochemistry. Biological evaluation, including wound healing, cell proliferation, and invasion of NPC cells, was also examined, and the correlation between HGF/Met expression of primary and metastatic tumor in NPC patients and clinical prognosis were also analyzed.Results: Met TKI inhibitor, PF-2341066, inhibited growth of NPC cells in vivo with half maximal inhibitory concentration of 0.79±0.21 µmol/L, and suppressed invasion and migration of NPC cells; also, the inhibition of PF-2341066 was synergized with cisplatin treatment. Compared with the control group, Met TKI inhibited metastasis of transplanted NPC in nude mice (the number of live metastases [mean ± SD]: 5.8±2.2 versus 11.8±2.2, P=0.03; the number of lung metastases: 2.3±1.5 versus

Isolation and characterization of anti c-met single chain fragment variable (scFv) antibodies.

Science.gov (United States)

Qamsari, Elmira Safaie; Sharifzadeh, Zahra; Bagheri, Salman; Riazi-Rad, Farhad; Younesi, Vahid; Abolhassani, Mohsen; Ghaderi, Sepideh Safaei; Baradaran, Behzad; Somi, Mohammad Hossein; Yousefi, Mehdi

2017-12-01

The receptor tyrosine kinase (RTK) Met is the cell surface receptor for hepatocyte growth factor (HGF) involved in invasive growth programs during embryogenesis and tumorgenesis. There is compelling evidence suggesting important roles for c-Met in colorectal cancer proliferation, migration, invasion, angiogenesis, and survival. Hence, a molecular inhibitor of an extracellular domain of c-Met receptor that blocks c-Met-cell surface interactions could be of great thera-peutic importance. In an attempt to develop molecular inhibitors of c-Met, single chain variable fragment (scFv) phage display libraries Tomlinson I + J against a specific synthetic oligopeptide from the extracellular domain of c-Met receptor were screened; selected scFv were then characterized using various immune techniques. Three c-Met specific scFv (ES1, ES2, and ES3) were selected following five rounds of panning procedures. The scFv showed specific binding to c-Met receptor, and significantly inhibited proliferation responses of a human colorectal carcinoma cell line (HCT-116). Moreover, anti- apoptotic effects of selected scFv antibodies on the HCT-116 cell line were also evaluated using Annexin V/PI assays. The results demonstrated rates of apoptotic cell death of 46.0, 25.5, and 37.8% among these cells were induced by use of ES1, ES2, and ES3, respectively. The results demonstrated ability to successfully isolate/char-acterize specific c-Met scFv that could ultimately have a great therapeutic potential in immuno-therapies against (colorectal) cancers.

Characterization of HGF/Met Signaling in Cell Lines Derived From Urothelial Carcinoma of the Bladder

Energy Technology Data Exchange (ETDEWEB)

Lee, Young H. [Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Apolo, Andrea B. [Genitourinary Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States); Agarwal, Piyush K.; Bottaro, Donald P., E-mail: dbottaro@helix.nih.gov [Urologic Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

2014-11-25

There is mounting evidence of oncogenic hepatocyte growth factor (HGF)/Met signaling in urothelial carcinoma (UC) of the bladder. The effects of three kinase inhibitors, cabozantinib, crizotinib and EMD1214063, on HGF-driven signaling and cell growth, invasion and tumorigenicity were analyzed in cultured UC cell lines. SW780 xenograft growth in SCID and human HGF knock-in SCID (hHGF/SCID) mice treated with cabozantinib or vehicle, as well as tumor levels of Met and pMet, were also determined. Met content was robust in most UC-derived cell lines. Basal pMet content and effector activation state in quiescent cells were low, but significantly enhanced by added HGF, as were cell invasion, proliferation and anchorage independent growth. These HGF-driven effects were reversed by Met inhibitor treatment. Tumor xenograft growth was significantly higher in hHGF/SCID mice vs. SCID mice and significantly inhibited by cabozantinib, as was tumor phospho-Met content. These studies indicate the prevalence and functionality of the HGF/Met signaling pathway in UC cells, suggest that paracrine HGF may contribute to UC tumor growth and progression, and that support further preclinical investigation of Met inhibitors for the treatment of UC is warranted.

METs in adults while playing active video games: a metabolic chamber study.

Science.gov (United States)

Miyachi, Motohiko; Yamamoto, Kenta; Ohkawara, Kazunori; Tanaka, Shigeho

2010-06-01

Active video game systems controlled through arm gestures and motions (Nintendo Wii Sports) and video games controlled through force plate (Wii Fit Plus) are becoming increasingly popular. This study was performed to determine the energy expenditure (EE) during Wii Fit Plus and Wii Sports game activities. Twelve adult men and women performed all the activities of Wii Sports (five activities: golf, bowling, tennis, baseball, and boxing) and Wii Fit Plus (63 activities classified as yoga, resistance, balance, and aerobic exercises). Each activity was continued for at least 8 min to obtain a steady-state EE. Because EE was assessed in an open-circuit indirect metabolic chamber consisting of an airtight room (20,000 or 15,000 L), subjects were freed of apparatus to collect expired gas while playing the games. MET value was calculated from resting EE and steady-state EE during activity. The mean MET values of all 68 activities were distributed over a wide range from 1.3 METs (Lotus Focus) to 5.6 METs (single-arm stand). The mean MET values in yoga, balance, resistance, and aerobic exercise of Wii Fit Plus and Wii Sports were 2.1, 2.0, 3.2, 3.4, and 3.0 METs, respectively. Forty-six activities (67%) were classified as light intensity (6.0 METs). Time spent playing one-third of the activities supplied by motion- and gesture-controlled video games can count toward the daily amount of exercise required according to the guidelines provided by the American College of Sports Medicine and the American Heart Association, which focus on 30 min of moderate-intensity daily physical activity 5 d x wk(-1).

COMT Val158Met polymorphism, cognitive stability and cognitive flexibility: an experimental examination

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Rosa Elise C

2010-09-01

Full Text Available Abstract Background Dopamine in prefrontal cortex (PFC modulates core cognitive processes, notably working memory and executive control. Dopamine regulating genes and polymorphisms affecting PFC - including Catechol-O-Methyltransferase (COMT Val158Met - are crucial to understanding the molecular genetics of cognitive function and dysfunction. A mechanistic account of the COMT Val158Met effect associates the Met allele with increased tonic dopamine transmission underlying maintenance of relevant information, and the Val allele with increased phasic dopamine transmission underlying the flexibility of updating new information. Thus, consistent with some earlier work, we predicted that Val carriers would display poorer performance when the maintenance component was taxed, while Met carriers would be less efficient when rapid updating was required. Methods Using a Stroop task that manipulated level of required cognitive stability and flexibility, we examined reaction time performance of patients with schizophrenia (n = 67 and healthy controls (n = 186 genotyped for the Val/Met variation. Results In both groups we found a Met advantage for tasks requiring cognitive stability, but no COMT effect when a moderate level of cognitive flexibility was required, or when a conflict cost measure was calculated. Conclusions Our results do not support a simple stability/flexibility model of dopamine COMT Val/Met effects and suggest a somewhat different conceptualization and experimental operationalization of these cognitive components.

The implementation of modern digital technology in x-ray medical diagnosis in Republic of Moldova - a stringent necessity

International Nuclear Information System (INIS)

Rosca, Andrei

2011-01-01

The study includes analyses of current technical state of radiodiagnostic equipment from the Public Medico-Sanitary Institution of Ministry of Health of Republic of Moldova (IMSP MS RM). The traditional radiodiagnostic apparatuses were morally and physically outrun at 96,6% (in regional MSPI - 93,5%), inclusive the dental one - 92,0% (in raional MSPI - 97,2%), X-Ray exam -100%, mobile - 84,1% etc. The exploitation of the traditional radiodiagnostic apparatuses with high degree of physical and moral wear essentially diminished the quality of profile investigation, creates premises for diagnostic error perpetrating, increase the collective ionizing irradiation of population etc. In recent years the subvention of MSPI HM RM with digital radiodiagnostic equipment was started. This process is very hard unfold because of grave socio-economic crises in Republic of Moldova. Despite these obstacles the subvention of MSPI HM RM with digital equipment represents a stringent necessity and a time request.

Towards the Development of Clinical Measures for Spinal Cord Injury Based on the International Classification of Functioning, Disability and Health With Rasch Analyses

DEFF Research Database (Denmark)

Ballert, Carolina S; Stucki, Gerold; Biering-Sørensen, Fin

2014-01-01

item dependency was observed between ICF categories of the same chapters. Group effects for age and sex were observed only to a small extent. CONCLUSIONS: The validity of ICF categories to develop measures of functioning in SCI for clinical practice and research is to some extent supported. Model......OBJECTIVES: To determine whether the International Classification of Functioning, Disability and Health (ICF) categories relevant to spinal cord injury (SCI) can be integrated in clinical measures and to obtain insights to guide their future operationalization. Specific aims are to find out whether...... in specialized centers within 15 countries from 2006 through 2008. SETTING: Secondary data analysis. PARTICIPANTS: Adults (N=1048) with SCI from the early postacute and long-term living context. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Two unidimensional Rasch analyses: one for the ICF categories...

Vigas de madera laminada Glulam reforzadas con pletinas metálicas dentadas

OpenAIRE

Cañola, Hernán Darío

2015-01-01

En esta tesis se estudian las propiedades mecánicas de vigas de madera maciza y de madera laminada Glulam reforzadas con pletinas metálicas dentadas. Se fabricaron y analizaron experimentalmente cuatro grupos diferentes de vigas: 30 vigas de madera maciza no reforzadas, 30 vigas de madera maciza reforzadas con pletinas metálicas dentadas, 30 vigas de madera laminada Glulam no reforzadas y 30 vigas de madera laminada Glulam reforzadas con pletinas metálicas dentadas. Las vigas de madera ...

The rapidly evolving centromere-specific histone has stringent functional requirements in Arabidopsis thaliana.

Science.gov (United States)

Ravi, Maruthachalam; Kwong, Pak N; Menorca, Ron M G; Valencia, Joel T; Ramahi, Joseph S; Stewart, Jodi L; Tran, Robert K; Sundaresan, Venkatesan; Comai, Luca; Chan, Simon W-L

2010-10-01

Centromeres control chromosome inheritance in eukaryotes, yet their DNA structure and primary sequence are hypervariable. Most animals and plants have megabases of tandem repeats at their centromeres, unlike yeast with unique centromere sequences. Centromere function requires the centromere-specific histone CENH3 (CENP-A in human), which replaces histone H3 in centromeric nucleosomes. CENH3 evolves rapidly, particularly in its N-terminal tail domain. A portion of the CENH3 histone-fold domain, the CENP-A targeting domain (CATD), has been previously shown to confer kinetochore localization and centromere function when swapped into human H3. Furthermore, CENP-A in human cells can be functionally replaced by CENH3 from distantly related organisms including Saccharomyces cerevisiae. We have used cenh3-1 (a null mutant in Arabidopsis thaliana) to replace endogenous CENH3 with GFP-tagged variants. A H3.3 tail domain-CENH3 histone-fold domain chimera rescued viability of cenh3-1, but CENH3's lacking a tail domain were nonfunctional. In contrast to human results, H3 containing the A. thaliana CATD cannot complement cenh3-1. GFP-CENH3 from the sister species A. arenosa functionally replaces A. thaliana CENH3. GFP-CENH3 from the close relative Brassica rapa was targeted to centromeres, but did not complement cenh3-1, indicating that kinetochore localization and centromere function can be uncoupled. We conclude that CENH3 function in A. thaliana, an organism with large tandem repeat centromeres, has stringent requirements for functional complementation in mitosis.

"Met" Made Simple: Building Research-Based Teacher Evaluations. Issue Analysis Report

Science.gov (United States)

New Teacher Project, 2012

2012-01-01

Groundbreaking new findings from the Bill and Melinda Gates Foundation's Measures of Effective Teaching (MET) project hold the potential to answer crucial questions about how to assess teachers' performance. For the past two years, MET researchers have conducted a research project of unprecedented scope, involving 3,000 teachers in six school…

Genetic contribution of catechol-O-methyltransferase polymorphism (Val158Met) in children with chronic tension-type headache.

Science.gov (United States)

Fernández-de-las-Peñas, César; Ambite-Quesada, Silvia; Rivas-Martínez, Inés; Ortega-Santiago, Ricardo; de-la-Llave-Rincón, Ana Isabel; Fernández-Mayoralas, Daniel M; Pareja, Juan A

2011-10-01

Our aim was to investigate the relationship between Val158Met polymorphisms, headache, and pressure hypersensitivity in children with chronic tension-type headache (CTTH). A case-control study with blinded assessor was conducted. Seventy children with CTTH associated with pericranial tenderness and 70 healthy children participated. After amplifying Val158Met polymorphism by polymerase chain reactions, we assessed genotype frequencies and allele distributions. We classified children according to their Val158Met polymorphism: Val/Val, Val/Met, Met/Met. Pressure pain thresholds (PPT) were bilaterally assessed over the temporalis, upper trapezius, second metacarpal, and tibialis anterior muscles. The distribution of Val158Met genotypes was not significantly different (p = 0.335), between children with CTTH and healthy children, and between boys and girls (p = 0.872). Children with CTTH with the Met/Met genotype showed a longer headache history compared with those with Met/Val (p = 0.001) or Val/Val (p = 0.002) genotype. Children with CTTH with Met/Met genotype showed lower PPT over upper trapezius and temporalis muscles than children with CTTH with Met/Val or Val/Val genotype (p < 0.01). The Val158Met catechol-O-methyltransferase (COMT) polymorphism does not appear to be involved in predisposition to suffer from CTTH in children; nevertheless, this genetic factor may be involved in the phenotypic expression, as pressure hypersensitivity was greater in those CTTH children with the Met/Met genotype.

Targeting the MET oncogene by concomitant inhibition of receptor and ligand via an antibody-"decoy" strategy.

Science.gov (United States)

Basilico, Cristina; Modica, Chiara; Maione, Federica; Vigna, Elisa; Comoglio, Paolo M

2018-04-25

MET, a master gene sustaining "invasive growth," is a relevant target for cancer precision therapy. In the vast majority of tumors, wild-type MET behaves as a "stress-response" gene and relies on the ligand (HGF) to sustain cell "scattering," invasive growth and apoptosis protection (oncogene "expedience"). In this context, concomitant targeting of MET and HGF could be crucial to reach effective inhibition. To test this hypothesis, we combined an anti-MET antibody (MvDN30) inducing "shedding" (i.e., removal of MET from the cell surface), with a "decoy" (i.e., the soluble extracellular domain of the MET receptor) endowed with HGF-sequestering ability. To avoid antibody/decoy interaction-and subsequent neutralization-we identified a single aminoacid in the extracellular domain of MET-lysine 842-that is critical for MvDN30 binding and engineered the corresponding recombinant decoyMET (K842E). DecoyMET K842E retains the ability to bind HGF with high affinity and inhibits HGF-induced MET phosphorylation. In HGF-dependent cellular models, MvDN30 antibody and decoyMET K842E used in combination cooperate in restraining invasive growth, and synergize in blocking cancer cell "scattering." The antibody and the decoy unbridle apoptosis of colon cancer stem cells grown in vitro as spheroids. In a preclinical model, built by orthotopic transplantation of a human pancreatic carcinoma in SCID mice engineered to express human HGF, concomitant treatment with antibody and decoy significantly reduces metastatic spread. The data reported indicate that vertical targeting of the MET/HGF axis results in powerful inhibition of ligand-dependent MET activation, providing proof of concept in favor of combined target therapy of MET "expedience." © 2018 UICC.

MET-RODOS: A comprehensive atmospheric dispersion module

DEFF Research Database (Denmark)

Mikkelsen, T.; Thykier-Nielsen, S.; Astrup, P.

1997-01-01

A comprehensive meteorological dispersion module called MET-RODOS is being developed to serve the real-time RODOS(1-3) decision support system with an integrated prediction capability for airborne radioactive spread, deposition and gamma radiation exposure on all scales. Deposition, ground level ...

Mice with GFAP-targeted loss of neurofibromin demonstrate increased axonal MET expression with aging.

Science.gov (United States)

Su, Weiping; Xing, Rubing; Guha, Abhijit; Gutmann, David H; Sherman, Larry S

2007-05-01

Neurofibromatosis 1 (NF1) is a common genetic disease that predisposes patients to peripheral nerve tumors and central nervous system (CNS) abnormalities including low-grade astrocytomas and cognitive disabilities. Using mice with glial fibrillary acidic protein (GFAP)-targeted Nf1 loss (Nf1(GFAP)CKO mice), we found that Nf1(-/-) astrocytes proliferate faster and are more invasive than wild-type astrocytes. In light of our previous finding that aberrant expression of the MET receptor tyrosine kinase contributes to the invasiveness of human NF1-associated malignant peripheral nerve sheath tumors, we sought to determine whether MET expression is aberrant in the brains of Nf1 mutant mice. We found that Nf1(-/-) astrocytes express slightly more MET than wild-type cells in vitro, but do not express elevated MET in situ. However, fiber tracts containing myelinated axons in the hippocampus, midbrain, cerebral cortex, and cerebellum express higher than normal levels of MET in older (> or =6 months) Nf1(GFAP)CKO mice. Both Nf1(GFAP)CKO and wild-type astrocytes induced MET expression in neurites of wild-type hippocampal neurons in vitro, suggesting that astrocyte-derived signals may induce MET in Nf1 mutant mice. Because the Nf1 gene product functions as a RAS GTPase, we examined MET expression in the brains of mice with GFAP-targeted constitutively active forms of RAS. MET was elevated in axonal fiber tracts in mice with active K-RAS but not H-RAS. Collectively, these data suggest that loss of Nf1 in either astrocytes or GFAP(+) neural progenitor cells results in increased axonal MET expression, which may contribute to the CNS abnormalities in children and adults with NF1. (c) 2007 Wiley-Liss, Inc.

Hepatocyte growth factor/scatter factor-MET signaling in neural crest-derived melanocyte development.

Science.gov (United States)

Kos, L; Aronzon, A; Takayama, H; Maina, F; Ponzetto, C; Merlino, G; Pavan, W

1999-02-01

The mechanisms governing development of neural crest-derived melanocytes, and how alterations in these pathways lead to hypopigmentation disorders, are not completely understood. Hepatocyte growth factor/scatter factor (HGF/SF) signaling through the tyrosine-kinase receptor, MET, is capable of promoting the proliferation, increasing the motility, and maintaining high tyrosinase activity and melanin synthesis of melanocytes in vitro. In addition, transgenic mice that ubiquitously overexpress HGF/SF demonstrate hyperpigmentation in the skin and leptomenigenes and develop melanomas. To investigate whether HGF/ SF-MET signaling is involved in the development of neural crest-derived melanocytes, transgenic embryos, ubiquitously overexpressing HGF/SF, were analyzed. In HGF/SF transgenic embryos, the distribution of melanoblasts along the characteristic migratory pathway was not affected. However, additional ectopically localized melanoblasts were also observed in the dorsal root ganglia and neural tube, as early as 11.5 days post coitus (p.c.). We utilized an in vitro neural crest culture assay to further explore the role of HGF/SF-MET signaling in neural crest development. HGF/SF added to neural crest cultures increased melanoblast number, permitted differentiation into pigmented melanocytes, promoted melanoblast survival, and could replace mast-cell growth factor/Steel factor (MGF) in explant cultures. To examine whether HGF/SF-MET signaling is required for the proper development of melanocytes, embryos with a targeted Met null mutation (Met-/-) were analysed. In Met-/- embryos, melanoblast number and location were not overtly affected up to 14 days p.c. These results demonstrate that HGF/SF-MET signaling influences, but is not required for, the initial development of neural crest-derived melanocytes in vivo and in vitro.

La metáfora como proceso cognitivo

Directory of Open Access Journals (Sweden)

Luz Amparo Fajardo Uribe

2006-01-01

Full Text Available La metáfora es un mecanismo que hace posible conceptualizar y reconceptualizar el mundo a partir de la traslación de rasgos de un dominio de origen a un dominio de llegada. En esa medida, la metáfora no necesita inventar nuevos términos para referirse a la realidad, sino que a partir de los ya existentes brinda una visión diferente de ésta en tanto que ha sido enriquecida con la afectividad y la emotividad del sujeto cognoscente. Por esa razón, la comprensión y producción metafórica requiere más de la competencia comunicativa que de la competencia lingüística, dado que el sentido que éste adopta depende del contexto comunicativo y no de la constitución léxica, morfológica sintáctica del enunciado.

Inhaken met sociale media in 60 minuten

NARCIS (Netherlands)

Thijs Waardenburg; Komala Mazerant

2018-01-01

Met creatieve content die slim inhaakt op actuele gebeurtenissen kun je elke dag nieuwe mensen bereiken. Goedkoper dan adverteren op sociale media, en sympathieker bovendien.Thijs Waardenburg en Komala Mazerant leggen uit hoe je kansrijke inhakers bedenkt en communiceert om je bereik op sociale

The Pleiotropic MET Receptor Network: Circuit Development and the Neural-Medical Interface of Autism.

Science.gov (United States)

Eagleson, Kathie L; Xie, Zhihui; Levitt, Pat

2017-03-01

People with autism spectrum disorder and other neurodevelopmental disorders (NDDs) are behaviorally and medically heterogeneous. The combination of polygenicity and gene pleiotropy-the influence of one gene on distinct phenotypes-raises questions of how specific genes and their protein products interact to contribute to NDDs. A preponderance of evidence supports developmental and pathophysiological roles for the MET receptor tyrosine kinase, a multifunctional receptor that mediates distinct biological responses depending upon cell context. MET influences neuron architecture and synapse maturation in the forebrain and regulates homeostasis in gastrointestinal and immune systems, both commonly disrupted in NDDs. Peak expression of synapse-enriched MET is conserved across rodent and primate forebrain, yet regional differences in primate neocortex are pronounced, with enrichment in circuits that participate in social information processing. A functional risk allele in the MET promoter, enriched in subgroups of children with autism spectrum disorder, reduces transcription and disrupts socially relevant neural circuits structurally and functionally. In mice, circuit-specific deletion of Met causes distinct atypical behaviors. MET activation increases dendritic complexity and nascent synapse number, but synapse maturation requires reductions in MET. MET mediates its specific biological effects through different intracellular signaling pathways and has a complex protein interactome that is enriched in autism spectrum disorder and other NDD candidates. The interactome is coregulated in developing human neocortex. We suggest that a gene as pleiotropic and highly regulated as MET, together with its interactome, is biologically relevant in normal and pathophysiological contexts, affecting central and peripheral phenotypes that contribute to NDD risk and clinical symptoms. Copyright © 2016 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Physiological Signaling and Structure of the HGF Receptor MET

Directory of Open Access Journals (Sweden)

Gianluca Baldanzi

2014-12-01

Full Text Available The “hepatocyte growth factor” also known as “scatter factor”, is a multifunctional cytokine with the peculiar ability of simultaneously triggering epithelial cell proliferation, movement and survival. The combination of those proprieties results in the induction of an epithelial to mesenchymal transition in target cells, fundamental for embryogenesis but also exploited by tumor cells during metastatization. The hepatocyte growth factor receptor, MET, is a proto-oncogene and a prototypical transmembrane tyrosine kinase receptor. Inhere we discuss the MET molecular structure and the hepatocyte growth factor driven physiological signaling which coordinates epithelial proliferation, motility and morphogenesis.

Met zorg ondernemen: Bouwstenen voor succesvolle samenwerking tussen ondernemers en langdurige zorg

NARCIS (Netherlands)

Mogendorff, K.

2007-01-01

Het project Samenwerking tussen langdurige zorg en leidinggevenden (in het bedrijfsleven) wil relevante partijen inspireren en stimuleren om meer met elkaar te gaan samenwerken om zo doelstellingen als het vergroten van de maatschappelijke participatie van mensen met een langdurige zorgbehoefte te

Role of Methoprene-tolerant (Met in adult morphogenesis and in adult ecdysis of Blattella germanica.

Directory of Open Access Journals (Sweden)

Jesus Lozano

Full Text Available Juvenile Hormone (JH represses metamorphosis of young instars in insects. One of the main players in hormonal signalling is Methoprene-tolerant (Met, which plays the role of JH receptor. Using the Polyneopteran insect Blattella germanica as the model and RNAi for transcript depletion, we have confirmed that Met transduces the antimetamorphic signal of JH in young nymphs and plays a role in the last nymphal instar moult in this species. Previously, the function of Met as the JH receptor had been demonstrated in the Eumetabola clade, with experiments in Holometabola (in the beetle Tribolium castaneum and in their sister group Paraneoptera (in the bug Pyrrhocoris apterus. Our result shows that the function of Met as JH receptor is also conserved in the more basal Polyneoptera. The function of Met as JH transducer might thus predate the evolutionary innovation of metamorphosis. Moreover, expression of Met was also found in last nymphal instar of B. germanica, when JH is absent. Depletion of Met in this stage provoked deficiencies in wing growth and ecdysis problems in the imaginal moult. Down-regulation of the ecdysone-inducible gene E75A and Insulin-Like-Peptide 1 in these Met-depleted specimens suggest that Met is involved in the ecdysone and insulin signalling pathways in last nymphal instar, when JH is virtually absent.

Met flora meer fauna de stad in trekken

NARCIS (Netherlands)

Hoffman, M.H.A.

2010-01-01

Meer flora en fauna in de stedelijke omgeving begint met de aanplant van gevarieerd groen. Plant Publicity Holland geeft in een overzicht aan welke bomen, heesters en vaste planten daarvoor geschikt zijn.

The regulatory role of heparin on c-Met signaling in hepatocellular carcinoma cells.

Science.gov (United States)

İşcan, Evin; Güneş, Aysim; Korhan, Peyda; Yılmaz, Yeliz; Erdal, Esra; Atabey, Neşe

2017-06-01

The role of heparin as an anticoagulant is well defined; however, its role in tumorigenesis and tumor progression is not clear yet. Some studies have shown that anticoagulant treatment in cancer patients improve overall survival, however, recent clinical trials have not shown a survival benefit in cancer patients receiving heparin treatment. In our previous studies we have shown the inhibitory effects of heparin on Hepatocyte Growth Factor (HGF)-induced invasion and migration in hepatocellular carcinoma (HCC) cells. In this study, we showed the differential effects of heparin on the behaviors of HCC cells based on the presence or absence of HGF. In the absence of HGF, heparin activated HGF/c-Met signaling and promoted motility and invasion in HCC cells. Heparin treatment led to c-Met receptor dimerization and activated c-Met signaling in an HGF independent manner. Heparin-induced c-Met activation increased migration and invasion through ERK1/2, early growth response factor 1 (EGR1) and Matrix Metalloproteinases (MMP) axis. Interestingly, heparin modestly decreased the proliferation of HCC cells by inhibiting activatory phosphorylation of Akt. The inhibition of c-Met signaling reversed heparin-induced increase in motility and invasion and, proliferation inhibition. Our study provides a new perspective into the role of heparin on c-Met signaling in HCC.

Are Dutch residents ready for a more stringent policy to enhance the energy performance of their homes?

International Nuclear Information System (INIS)

Middelkoop, Manon van; Vringer, Kees; Visser, Hans

2017-01-01

Investments in the energy performance of houses offer good prospects for reducing energy consumption and CO_2 emissions. However, people are not easily convinced of the need to take measures to improve the energy performance of their houses, even when financial benefits outweigh the costs. This article analyses the factors that influence the decision for improving the energy performance of existing homes, including policy instruments. Subsequently, the article provides policy suggestions on how to stimulate energy performance improvements. Both owners and tenants (50–70%) support government policy on energy performance improvements to existing homes. Nevertheless, people also have strong feelings of autonomy regarding their homes. Our results underline the importance of well-informed and competent decision-makers. Introducing the use of Energy Performance Certificates (EPCs) into the tax system for energy and residential buildings might therefore be an effective way to increase the interest of owners in the EPC, improve the use and effect of this informative instrument, and make the first step towards bridging the tension between autonomy and more stringent instruments.

Opioid-dependent growth of glial cultures: Suppression of astrocyte DNA synthesis by met-enkephalin

International Nuclear Information System (INIS)

Stiene-Martin, A.; Hauser, K.F.

1990-01-01

The action of met-enkephalin on the growth of astrocytes in mixed-glial cultures was examined. Primary, mixed-glial cultures were isolated from 1 day-old mouse cerebral hemispheres and continuously treated with either basal growth media, 1 μM met-enkephalin, 1 μM met-enkephalin plus the opioid antagonist naloxone, or naloxone alone. Absolute numbers of neural cells were counted in unstained preparations, while combined [ 3 H]-thymidine autoradiography and glial fibrillary acid protein (GFAP) immunocytochemistry was performed to identify specific changes in astrocytes. When compared to control and naloxone treated cultures, met-enkephalin caused a significant decrease in both total cell numbers, and in [ 3 H]-thymidine incorporation by GFAP-positive cells with flat morphology. These results indicate that met-enkephalin suppresses astrocyte growth in culture

Opioid-dependent growth of glial cultures: Suppression of astrocyte DNA synthesis by met-enkephalin

Energy Technology Data Exchange (ETDEWEB)

Stiene-Martin, A.; Hauser, K.F. (Univ. of Kentucky, Lexington (USA))

1990-01-01

The action of met-enkephalin on the growth of astrocytes in mixed-glial cultures was examined. Primary, mixed-glial cultures were isolated from 1 day-old mouse cerebral hemispheres and continuously treated with either basal growth media, 1 {mu}M met-enkephalin, 1 {mu}M met-enkephalin plus the opioid antagonist naloxone, or naloxone alone. Absolute numbers of neural cells were counted in unstained preparations, while combined ({sup 3}H)-thymidine autoradiography and glial fibrillary acid protein (GFAP) immunocytochemistry was performed to identify specific changes in astrocytes. When compared to control and naloxone treated cultures, met-enkephalin caused a significant decrease in both total cell numbers, and in ({sup 3}H)-thymidine incorporation by GFAP-positive cells with flat morphology. These results indicate that met-enkephalin suppresses astrocyte growth in culture.

Ervaringen met ICT-onderzoek in het HBO.

NARCIS (Netherlands)

van Leeuwen, H.; Teeuw, W.J.; Tangelder, R.; Griffioen, P.; Krose, B.; Schouten, B.

2011-01-01

In dit artikel wordt het belang aangegeven van onderzoeksvaardigheden in het HBO. Met de komst van de lectoraten en de nieuwe positionering van het HBO is het belangrijk om een antwoord te vinden hoe het onderzoek binnen het HBO vormgegeven moet worden. Hierbij wordt gekeken naar de bruikbaarheid

MetNet - In situ observational Network and Orbital platform to investigate the Martian environment

Science.gov (United States)

Harri, Ari-Matti; Leinonen, Jussi; Merikallio, Sini; Paton, Mark; Haukka, Harri; Polkko, Jouni

2007-09-01

MetNet Mars Mission is an in situ observational network and orbital platform mission to investigate the Martian environment and it has been proposed to European Space Agency in response to Call for proposals for the first planning cycle of Cosmic Vision 2015-2025 D/SCI/DJS/SV/val/21851. The MetNet Mars Mission is to be implemented in collaboration with ESA, FMI, LA, IKI and the payload providing science teams. The scope of the MetNet Mission is to deploy 16 MetNet Landers (MNLs) on the Martian surface by using inflatable descent system structures accompanied by an atmospheric sounder and data relay onboard the MetNet Orbiter (MNO), which is based on ESA Mars Express satellite platform. The MNLs are attached on the three sides of the satellite and most of the MNLs are deployed to Mars separately a few weeks prior to the arrival to Mars. The MetNet Orbiter will perform continuous atmospheric soundings thus complementing the accurate in situ observations at the Martian ground produced by the MetNet observation network, as well as the orbiter will serve as the primary data relay between the MetNet Landers and the Earth. The MNLs are equipped with a versatile science payload focused on the atmospheric science of Mars. Detailed characterisation of the Martian atmospheric circulation patterns, boundary layer phenomena, and climatological cycles, as well as interior investigations, require simultaneous in situ meteorological, seismic and magnetic measurements from networks of stations on the Martian surface. MetNet Mars Mission will also provide a crucial support for the safety of large landing missions in general and manned Mars missions in particular. Accurate knowledge of atmospheric conditions and weather data is essential to guarantee safe landings of the forthcoming Mars mission elements.

'Mastspuit met sensoren brengt middel effectiever aan' (onderzoek praktijkproeven PRI en PPO)

NARCIS (Netherlands)

Engels, A.; PPO BBF Boomkwekerij,; PRI,; Nieuwenhuizen, A.T.

2011-01-01

In mei 2011 starten Plant Research International (PRI), PPO Boomkwekerij en Damcon de eerste praktijkproeven met sensoren op de mastspuit. Dit prototype spuit alleen als het bladeren detecteert. Projectleider Ard Nieuwenhuizen van PRI is ervan overtuigd dat kwekers met zo'n type spuit middelen

Preproghrelin Leu72Met polymorphism in patients with type 2 diabetes mellitus.

Science.gov (United States)

Ukkola, O; Kesäniemi, Y A

2003-10-01

The association between the Leu72Met polymorphism of the preproghrelin gene and diabetic complications was examined in patients with type 2 diabetes mellitus. A total of 258 patients with type 2 diabetes mellitus and 522 control subjects were screened. Genotypes were determined by polymerase chain reaction technique. The diagnosis of coronary heart disease was based on clinical and ECG criteria. Laboratory analyses were carried out in the hospital laboratory. No differences in the genotype distributions and allele frequencies of the preproghrelin Leu72Met polymorphism were found between type 2 diabetes mellitus patients and controls. The polymorphism was not associated with macro- or micro-angiopathy or hypertension. However, Leu72Met polymorphism was associated with serum creatinine (P = 0.006) and lipoprotein(a) [Lp(a)] levels (P = 0.006) with Leu72Leu subjects showing the highest values. This association was observed only amongst diabetic group. The Leu72Met polymorphism of the preproghrelin gene was not related to cardiovascular disease in type 2 diabetes mellitus patients. Leu72Met polymorphism was, however, associated with serum creatinine and Lp(a) levels in diabetic patients. The mechanism might be associated with a possible change in ghrelin product and its somatotropic effect.

Expression and prognostic relevance of MET and phospho-BAD in non-small cell lung cancer.

Science.gov (United States)

Sun, Wenze; Ai, Ting; Gao, Ying; Zhang, Yingbing; Cui, Jie; Song, Liping

2013-01-01

MET is involved in the progression of several types of human cancers, while phospho-BAD(Ser-136) is a key molecule in apoptosis and might be regulated by MET. The aim of this study was to investigate the correlation between altered expression of MET and phospho-BAD in non-small cell lung cancer (NSCLC) and their association with clinicopathologic parameters and overall survival. MET and phospho-BAD(Ser-136) proteins were evaluated by immunohistochemical analysis in 183 paraffin-embedded specimens and were also assessed by Western blotting analysis in 12 frozen tumor tissue samples, which were representative examples of immunohistochemical staining. Positive expression of MET and phospho-BAD(Ser-136) occurred in 67.2% and 49.2% of the 183 cases of NSCLC, respectively. However, neither MET expression nor phospho-BAD(Ser-136) expression was associated with any clinicopathologic parameter. A significant correlation was found between MET and phospho-BAD(Ser-136) expression levels evaluated by immunohistochemistry (r = 0.268, P BAD(Ser-136)+ phenotype had a poorer prognosis than others (P BAD(Ser-136) expression, and may be an adverse predictor for NSCLC. Activation of the MET/phospho-BAD(Ser-136) signaling pathway might play a role in the development and progression of NSCLC.

The BDNF Val66Met Polymorphism Affects the Vulnerability of the Brain Structural Network

Directory of Open Access Journals (Sweden)

Chang-hyun Park

2017-08-01

Full Text Available Val66Met, a naturally occurring polymorphism in the human brain-derived neurotrophic factor (BDNF gene resulting in a valine (Val to methionine (Met substitution at codon 66, plays an important role in neuroplasticity. While the effect of the BDNF Val66Met polymorphism on local brain structures has previously been examined, its impact on the configuration of the graph-based white matter structural networks is yet to be investigated. In the current study, we assessed the effect of the BDNF polymorphism on the network properties and robustness of the graph-based white matter structural networks. Graph theory was employed to investigate the structural connectivity derived from white matter tractography in two groups, Val homozygotes (n = 18 and Met-allele carriers (n = 55. Although there were no differences in the global network measures including global efficiency, local efficiency, and modularity between the two genotype groups, we found the effect of the BDNF Val66Met polymorphism on the robustness properties of the white matter structural networks. Specifically, the white matter structural networks of the Met-allele carrier group showed higher vulnerability to targeted removal of central nodes as compared with those of the Val homozygote group. These findings suggest that the central role of the BDNF Val66Met polymorphism in regards to neuroplasticity may be associated with inherent differences in the robustness of the white matter structural network according to the genetic variants. Furthermore, greater susceptibility to brain disorders in Met-allele carriers may be understood as being due to their limited stability in white matter structural connectivity.

Voor elk-ander. Ervaringsdeskundigen met een lichte verstandelijke beperking en coaches over betekenisvolle samenwerking

Directory of Open Access Journals (Sweden)

Maaike Hermsen

2017-06-01

Full Text Available For each other. Experience experts with a mild intellectual disability and coaches on meaningful cooperation Collaboration with experience experts, particularly in mental healthcare, has flourished in recent years. The positive results of cooperating with experience experts in mental healthcare have led to more initiatives in other healthcare sectors too, such as in care for people with intellectual disabilities. Daily cooperation with experience experts with intellectual disabilities requires structural support, however, which is often provided by coaches in the workplace. This qualitative study aims to answer the question which knowledge, skills and attitudes are needed by coaches in order to support experience experts with intellectual disabilities. In addition, we look at what makes the cooperation with experience experts with an intellectual disability a meaningful process for all those involved. To answer these questions, individual interviews with experience experts with an intellectual disability and with coaches were conducted, as well as group interviews with teachers and researchers working with experience experts in practice. Current coaching guidelines emphasize responsibility, self-control and reflection on the part of the person being coached. However, this research shows that these basic principles are not sufficient for the specific nature of coaching experience experts with a mild intellectual disability. Voor elk-ander. Ervaringsdeskundigen met een lichte verstandelijke beperking en coaches over betekenisvolle samenwerkingSamenwerken met ervaringsdeskundigen neemt de laatste jaren, met name in de GGZ, een hoge vlucht. De positieve resultaten van de samenwerking met ervaringsdeskundigen in de GGZ hebben ertoe geleid dat er meer initiatieven komen in andere zorgsectoren, zo ook in de zorg aan mensen met een verstandelijke beperking. Samenwerking met ervaringsdeskundigen met een verstandelijke beperking vraagt in de dagelijkse

A metáfora na ensaística de Borges

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Gustavo Ponciano Cunha de Oliveira

2014-12-01

Full Text Available http://dx.doi.org/10.5007/2176-8552.2014n17p115 A metáfora é uma recorrência temática na ensaística de Jorge Luis Borges. Porém, o tratamento dado pelo autor portenho ao objeto ensaiado não foi sempre o mesmo. Do jovem poeta e ensaísta ultraísta ao maduro palestrante, as concepções foram profundamente alteradas. Neste ensaio, pretendemos passar por estas diversificadas concepções para nos concentrarmos em uma delas: a metáfora entendida como possibilidade de convergência de conceitos diversos, mesmo contraditórios. Mais do que tema, defendemos a tese de que esta metáfora é própria ao funcionamento ensaístico de Borges. Para promover o debate, nos apoiamos em textos de Paul Ricoeur, Jaime Alazraki, Joseph Hillis Miller, Joaquina Navarro, Álvaro Salvador, entre outros.

Correlation among genetic variations of c-MET in Chinese patients with non-small cell lung cancer.

Science.gov (United States)

Duan, Jianchun; Yang, Xiaodan; Zhao, Jun; Zhuo, Minglei; Wang, Zhijie; An, Tongtong; Bai, Hua; Wang, Jie

2018-01-05

The purpose of our research was to determine the correlation of amplification, protein expression and somatic mutation of c-MET in IIIb-IV stage NSCLC (Non-small cell lung cancer). We also explored correlation of c-MET variation with clinical outcome. c-MET expression was observed in 28.6% (56/196) cases, and among those 13.8% (27/196) were shown to be FISH positive. Only 2.67% patients in this study carried the c-MET mutation. Cases with c-MET FISH positive were all IHC positive ,but in IHC positive cases, only half were FISH positive. Among patients with IHC 2+ staining, 35.5% was FISH positive, while cases with IHC 3+ staining,64% was FISH positive. Both protein expression and copy number of c-MET did not significantly correlate with clinical prognosis in these patients treated with EGFR-TKIs. IHC could be used as a preliminary screening method for c-MET copy number amplification and should be confirmed by FISH only in IHC positive case which facilitate selection of ALK or MET inhibitor therapy. c-MET gene copy number, protein expression and somatic mutation for exon 14 were detected by fluorescent- In-Situ -Hybridization (FISH), Immunohistochemistry (IHC), and Denaturing-High-Performance-Liquid-Chromatography (DHPLC), respectively, in 196 NSCLC patients. The relationship between c-MET abnormalities and clinical outcome of targeted therapy was analyzed by McNemar's test.

Patienten met diabetes Mellitus type 1 screenen op coeliakie; Ja of nee

NARCIS (Netherlands)

Greijdanus, T.

2005-01-01

Diabetes mellitus type 1 is een veelvoorkomende ziekte. Deze ziekte blijkt niet op zichzelf te staan maar is onder andere geassocieerd met coeliakie. Coeliakie wordt behandeld middels een glutenvrij dieet. De diabetespatiënten die aan coeliakie lijden blijken zich niet altijd bij de huisarts met

Radioimmunoassay of met-enkephalin in microdissected areas of paraformaldehyde-fixed rat brain

International Nuclear Information System (INIS)

Correa, F.M.A.; Saavedra, J.M.

1984-01-01

The effects were studied of various sample preparation procedures on rat brain met-enkephalin content, measured by radioimmunoassay. Whole brain met-enkephalin content of rats killed by decapitation followed by immediate tissue freezing was similar to that of rats killed by microwave irradiation and to those of rats anesthetized with pentobarbital or halothane before killing, whether previously perfused with paraformaldehyde or not. In contrast, a decrease (up to 80%) in met-enkephalin concentrations was observed when brain samples were frozen and thawed to mimic the procedure utilized in the ''punch'' technique for analysis of discrete brain nuclei. This decrease was totally prevented by paraformaldehyde perfusion of the brain prior to sacrifice. Brain perfusion did not alter the amount of immunoassayable met-enkephalin extracted from tissue or its profile after Sephadex chromatography. Paraformaldehyde perfusion results in better morphological tissue preservation and facilitates the ''punch'' dissecting technique. Paraformaldehyde perfusion may be the procedure of choice for the measurement of neuropeptides in specific brain nuclei dissected by the ''punch'' technique

Catechol-O-Methyltransferase (COMT) Gene (Val158Met) and Brain-Derived Neurotropic Factor (BDNF) (Val66Met) Genes Polymorphism in Schizophrenia: A Case-Control Study

OpenAIRE

Saravani, Ramin; Galavi, Hamid Reza; Lotfian Sargazi, Marzieh

2017-01-01

Objective: Several studies have shown that some polymorphisms of genes encoding catechol-O-methyltransferase (COMT), the key enzyme in degrading dopamine, and norepinephrine and the human brain-derived neurotropic factor (BDNF), a nerve growth factor, are strong candidates for risk of schizophrenia (SCZ). In the present study, we aimed at examining the effects of COMT Val158Met (G>A) and BDNF Val66Met (G>A) polymorphisms on SCZ risk in a sample of Iranian population. Method: This case- contro...

Complete or partial reduction of the Met receptor tyrosine kinase in distinct circuits differentially impacts mouse behavior.

Science.gov (United States)

Thompson, Barbara L; Levitt, Pat

2015-01-01

Our laboratory discovered that the gene encoding the receptor tyrosine kinase, MET, contributes to autism risk. Expression of MET is reduced in human postmortem temporal lobe in autism and Rett Syndrome. Subsequent studies revealed a role for MET in human and mouse functional and structural cortical connectivity. To further understand the contribution of Met to brain development and its impact on behavior, we generated two conditional mouse lines in which Met is deleted from select populations of central nervous system neurons. Mice were then tested to determine the consequences of disrupting Met expression. Mating of Emx1 (cre) and Met (fx/fx) mice eliminates receptor signaling from all cells arising from the dorsal pallium. Met (fx/fx) and Nestin (cre) crosses result in receptor signaling elimination from all neural cells. Behavioral tests were performed to assess cognitive, emotional, and social impairments that are observed in multiple neurodevelopmental disorders and that are in part subserved by circuits that express Met. Met (fx/fx) /Emx1 (cre) null mice displayed significant hypoactivity in the activity chamber and in the T-maze despite superior performance on the rotarod. Additionally, these animals showed a deficit in spontaneous alternation. Surprisingly, Met (fx/fx; fx/+) /Nestin (cre) null and heterozygous mice exhibited deficits in contextual fear conditioning, and Met (fx/+) /Nestin (cre) heterozygous mice spent less time in the closed arms of the elevated plus maze. These data suggest a complex contribution of Met in the development of circuits mediating social, emotional, and cognitive behavior. The impact of disrupting developmental Met expression is dependent upon circuit-specific deletion patterns and levels of receptor activity.

MET signalling in primary colon epithelial cells leads to increased transformation irrespective of aberrant Wnt signalling

Science.gov (United States)

Boon, E M J; Kovarikova, M; Derksen, P W B; van der Neut, R

2005-01-01

It has been shown that in hereditary and most sporadic colon tumours, components of the Wnt pathway are mutated. The Wnt target MET has been implicated in the development of colon cancer. Here, we show that overexpression of wild-type or a constitutively activated form of MET in colon epithelial cells leads to increased transformation irrespective of Wnt signalling. Fetal human colon epithelial cells without aberrant Wnt signalling were transfected with wild-type or mutated MET constructs. Expression of these constructs leads to increased phosphorylation of MET and its downstream targets PKB and MAPK. Upon stimulation with HGF, the expression of E-cadherin is downregulated in wild-type MET-transfected cells, whereas cells expressing mutated MET show low E-cadherin levels independent of stimulation with ligand. This implies a higher migratory propensity of these cells. Furthermore, fetal human colon epithelial cells expressing the mutated form of MET have colony-forming capacity in soft agar, while cells expressing wild-type MET show an intermediate phenotype. Subcutaneous injection of mutated MET-transfected cells in nude mice leads to the formation of tumours within 12 days in all mice injected. At this time point, mock-transfected cells do not form tumours, while wild-type MET-transfected cells form subcutaneous tumours in one out of five mice. We thus show that MET signalling can lead to increased transformation of colon epithelial cells independent of Wnt signalling and in this way could play an essential role in the onset and progression of colorectal cancer. PMID:15785735

Catechol-O-methyltransferase val158met polymorphism predicts placebo effect in irritable bowel syndrome.

Directory of Open Access Journals (Sweden)

Kathryn T Hall

Full Text Available Identifying patients who are potential placebo responders has major implications for clinical practice and trial design. Catechol-O-methyltransferase (COMT, an important enzyme in dopamine catabolism plays a key role in processes associated with the placebo effect such as reward, pain, memory and learning. We hypothesized that the COMT functional val158met polymorphism, was a predictor of placebo effects and tested our hypothesis in a subset of 104 patients from a previously reported randomized controlled trial in irritable bowel syndrome (IBS. The three treatment arms from this study were: no-treatment ("waitlist", placebo treatment alone ("limited" and, placebo treatment "augmented" with a supportive patient-health care provider interaction. The primary outcome measure was change from baseline in IBS-Symptom Severity Scale (IBS-SSS after three weeks of treatment. In a regression model, the number of methionine alleles in COMT val158met was linearly related to placebo response as measured by changes in IBS-SSS (p = .035. The strongest placebo response occurred in met/met homozygotes treated in the augmented placebo arm. A smaller met/met associated effect was observed with limited placebo treatment and there was no effect in the waitlist control. These data support our hypothesis that the COMT val158met polymorphism is a potential biomarker of placebo response.

COMT Val158 Met moderates the link between rank and aggression in a non-human primate.

Science.gov (United States)

Gutleb, D R; Roos, C; Noll, A; Ostner, J; Schülke, O

2018-04-01

The COMT Val 158 Met polymorphism is one of the most widely studied genetic polymorphisms in humans implicated in aggression and the moderation of stressful life event effects. We screened a wild primate population for polymorphisms at the COMT Val 158 Met site and phenotyped them for aggression to test whether the human polymorphism exists and is associated with variation in aggressive behavior. Subjects were all adults from 4 study groups (37 males, 40 females) of Assamese macaques (Macaca assamensis) in their natural habitat (Phu Khieo Wildlife Sanctuary, Thailand). We collected focal animal behavioral data (27 males, 36 females, 5964 focal hours) and fecal samples for non-invasive DNA analysis. We identified the human COMT Val 158 Met polymorphism (14 Met/Met, 41 Val/Met and 22 Val/Val). Preliminary results suggest that COMT genotype and dominance rank interact to influence aggression rates. Aggression rates increased with rank in Val/Val, but decreased in Met/Met and Val/Met individuals, with no significant main effect of COMT genotype on aggression. Further support for the interaction effect comes from time series analyses revealing that when changing from lower to higher rank position Val/Val individuals decreased, whereas Met/Met individuals increased their aggression rate. Contradicting the interpretation of earlier studies, we show that the widely studied Val 158 Met polymorphism in COMT is not unique to humans and yields similar behavioral phenotypes in a non-human primate. This study represents an important step towards understanding individual variation in aggression in a wild primate population and may inform human behavioral geneticists about the evolutionary roots of inter-individual variation in aggression. © 2017 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

Genomic profiling of a Hepatocyte growth factor-dependent signature for MET-targeted therapy in glioblastoma.

Science.gov (United States)

Johnson, Jennifer; Ascierto, Maria Libera; Mittal, Sandeep; Newsome, David; Kang, Liang; Briggs, Michael; Tanner, Kirk; Marincola, Francesco M; Berens, Michael E; Vande Woude, George F; Xie, Qian

2015-09-17

Constitutive MET signaling promotes invasiveness in most primary and recurrent GBM. However, deployment of available MET-targeting agents is confounded by lack of effective biomarkers for selecting suitable patients for treatment. Because endogenous HGF overexpression often causes autocrine MET activation, and also indicates sensitivity to MET inhibitors, we investigated whether it drives the expression of distinct genes which could serve as a signature indicating vulnerability to MET-targeted therapy in GBM. Interrogation of genomic data from TCGA GBM (Student's t test, GBM patients with high and low HGF expression, p ≤ 0.00001) referenced against patient-derived xenograft (PDX) models (Student's t test, sensitive vs. insensitive models, p ≤ 0.005) was used to identify the HGF-dependent signature. Genomic analysis of GBM xenograft models using both human and mouse gene expression microarrays (Student's t test, treated vs. vehicle tumors, p ≤ 0.01) were performed to elucidate the tumor and microenvironment cross talk. A PDX model with EGFR(amp) was tested for MET activation as a mechanism of erlotinib resistance. We identified a group of 20 genes highly associated with HGF overexpression in GBM and were up- or down-regulated only in tumors sensitive to MET inhibitor. The MET inhibitors regulate tumor (human) and host (mouse) cells within the tumor via distinct molecular processes, but overall impede tumor growth by inhibiting cell cycle progression. EGFR (amp) tumors undergo erlotinib resistance responded to a combination of MET and EGFR inhibitors. Combining TCGA primary tumor datasets (human) and xenograft tumor model datasets (human tumor grown in mice) using therapeutic efficacy as an endpoint may serve as a useful approach to discover and develop molecular signatures as therapeutic biomarkers for targeted therapy. The HGF dependent signature may serve as a candidate predictive signature for patient enrollment in clinical trials using MET inhibitors

Activation of c-MET induces a stem-like phenotype in human prostate cancer.

Directory of Open Access Journals (Sweden)

Geert J L H van Leenders

Full Text Available Prostate cancer consists of secretory cells and a population of immature cells. The function of immature cells and their mutual relation with secretory cells are still poorly understood. Immature cells either have a hierarchical relation to secretory cells (stem cell model or represent an inducible population emerging upon appropriate stimulation of differentiated cells. Hepatocyte Growth Factor (HGF receptor c-MET is specifically expressed in immature prostate cells. Our objective is to determine the role of immature cells in prostate cancer by analysis of the HGF/c-MET pathway.Gene-expression profiling of DU145 prostate cancer cells stimulated with HGF revealed induction of a molecular signature associated with stem cells, characterized by up-regulation of CD49b, CD49f, CD44 and SOX9, and down-regulation of CD24 ('stem-like signature'. We confirmed the acquisition of a stem-like phenotype by quantitative PCR, FACS analysis and Western blotting. Further, HGF led to activation of the stem cell related Notch pathway by up-regulation of its ligands Jagged-1 and Delta-like 4. Small molecules SU11274 and PHA665752 targeting c-MET activity were both able to block the molecular and biologic effects of HGF. Knock-down of c-MET by shRNA infection resulted in significant reduction and delay of orthotopic tumour-formation in male NMRI mice. Immunohistochemical analysis in prostatectomies revealed significant enrichment of c-MET positive cells at the invasive front, and demonstrated co-expression of c-MET with stem-like markers CD49b and CD49f.In conclusion, activation of c-MET in prostate cancer cells induced a stem-like phenotype, indicating a dynamic relation between differentiated and stem-like cells in this malignancy. Its mediation of efficient tumour-formation in vivo and predominant receptor expression at the invasive front implicate that c-MET regulates tumour infiltration in surrounding tissues putatively by acquisition of a stem-like phenotype.

BDNF val66met polymorphism affects aging of multiple types of memory.

Science.gov (United States)

Kennedy, Kristen M; Reese, Elizabeth D; Horn, Marci M; Sizemore, April N; Unni, Asha K; Meerbrey, Michael E; Kalich, Allan G; Rodrigue, Karen M

2015-07-01

The BDNF val66met polymorphism (rs6265) influences activity-dependent secretion of brain-derived neurotrophic factor in the synapse, which is crucial for learning and memory. Individuals homozygous or heterozygous for the met allele have lower BDNF secretion than val homozygotes and may be at risk for reduced declarative memory performance, but it remains unclear which types of declarative memory may be affected and how aging of memory across the lifespan is impacted by the BDNF val66met polymorphism. This cross-sectional study investigated the effects of BDNF polymorphism on multiple indices of memory (item, associative, prospective, subjective complaints) in a lifespan sample of 116 healthy adults aged 20-93 years. Advancing age showed a negative effect on item, associative and prospective memory, but not on subjective memory complaints. For item and prospective memory, there were significant age×BDNF group interactions, indicating the adverse effect of age on memory performance across the lifespan was much stronger in the BDNF met carriers than for the val homozygotes. BDNF met carriers also endorsed significantly greater subjective memory complaints, regardless of age, and showed a trend (pmemory performance compared to val homozygotes. These results suggest that genetic predisposition to the availability of brain-derived neurotrophic factor, by way of the BDNF val66met polymorphism, exerts an influence on multiple indices of episodic memory - in some cases in all individuals regardless of age (subjective memory and perhaps associative memory), in others as an exacerbation of age-related differences in memory across the lifespan (item and prospective memory). This article is part of a Special Issue entitled Memory & Aging. Copyright © 2014 Elsevier B.V. All rights reserved.

Development of a Computerized Adaptive Test of Children's Gross Motor Skills.

Science.gov (United States)

Huang, Chien-Yu; Tung, Li-Chen; Chou, Yeh-Tai; Wu, Hing-Man; Chen, Kuan-Lin; Hsieh, Ching-Lin

2018-03-01

To (1) develop a computerized adaptive test for gross motor skills (GM-CAT) as a diagnostic test and an outcome measure, using the gross motor skills subscale of the Comprehensive Developmental Inventory for Infants and Toddlers (CDIIT-GM) as the candidate item bank; and (2) examine the psychometric properties and the efficiency of the GM-CAT. Retrospective study. A developmental center of a medical center. Children with and without developmental delay (N=1738). Not applicable. The CDIIT-GM contains 56 universal items on gross motor skills assessing children's antigravity control, locomotion, and body movement coordination. The item bank of the GM-CAT had 44 items that met the dichotomous Rasch model's assumptions. High Rasch person reliabilities were found for each estimated gross motor skill for the GM-CAT (Rasch person reliabilities =.940-.995, SE=.68-2.43). For children aged 6 to 71 months, the GM-CAT had good concurrent validity (r values =.97-.98), adequate to excellent diagnostic accuracy (area under receiver operating characteristics curve =.80-.98), and moderate to large responsiveness (effect size =.65-5.82). The averages of items administered for the GM-CAT were 7 to 11, depending on the age group. The results of this study support the use of the GM-CAT as a diagnostic and outcome measure to estimate children's gross motor skills in both research and clinical settings. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

The importance of statistical modelling in clinical research : Comparing multidimensional Rasch-, structural equation and linear regression models for analyzing the depression of relatives of psychiatric patients.

Science.gov (United States)

Alexandrowicz, Rainer W; Jahn, Rebecca; Friedrich, Fabian; Unger, Anne

2016-06-01

Various studies have shown that caregiving relatives of schizophrenic patients are at risk of suffering from depression. These studies differ with respect to the applied statistical methods, which could influence the findings. Therefore, the present study analyzes to which extent different methods may cause differing results. The present study contrasts by means of one data set the results of three different modelling approaches, Rasch Modelling (RM), Structural Equation Modelling (SEM), and Linear Regression Modelling (LRM). The results of the three models varied considerably, reflecting the different assumptions of the respective models. Latent trait models (i. e., RM and SEM) generally provide more convincing results by correcting for measurement error and the RM specifically proves superior for it treats ordered categorical data most adequately.

Effects of the BDNF Val66Met Polymorphism on Anxiety-Like Behavior Following Nicotine Withdrawal in Mice.

Science.gov (United States)

Lee, Bridgin G; Anastasia, Agustin; Hempstead, Barbara L; Lee, Francis S; Blendy, Julie A

2015-12-01

Nicotine withdrawal is characterized by both affective and cognitive symptoms. Identifying genetic polymorphisms that could affect the symptoms associated with nicotine withdrawal are important in predicting withdrawal sensitivity and identifying personalized cessation therapies. In the current study we used a mouse model of a non-synonymous single nucleotide polymorphism in the translated region of the brain-derived neurotrophic factor (BDNF) gene that substitutes a valine (Val) for a methionine (Met) amino acid (Val66Met) to examine the relationship between the Val66Met single nucleotide polymorphism and nicotine dependence. This study measured proBDNF and the BDNF prodomain levels following nicotine and nicotine withdrawal and examined a mouse model of a common polymorphism in this protein (BDNF(Met/Met)) in three behavioral paradigms: novelty-induced hypophagia, marble burying, and the open-field test. Using the BDNF knock-in mouse containing the BDNF Val66Met polymorphism we found: (1) blunted anxiety-like behavior in BDNF(Met/Met) mice following withdrawal in three behavioral paradigms: novelty-induced hypophagia, marble burying, and the open-field test; (2) the anxiolytic effects of chronic nicotine are absent in BDNF(Met/Met) mice; and (3) an increase in BDNF prodomain in BDNF(Met/Met) mice following nicotine withdrawal. Our study is the first to examine the effect of the BDNF Val66Met polymorphism on the affective symptoms of withdrawal from nicotine in mice. In these mice, a single-nucleotide polymorphism in the translated region of the BDNF gene can result in a blunted withdrawal, as measured by decreased anxiety-like behavior. The significant increase in the BDNF prodomain in BDNF(Met/Met) mice following nicotine cessation suggests a possible role of this ligand in the circuitry remodeling after withdrawal. © The Author 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For

Cathecol-O-methyl transferase Val158Met genotype is not a risk factor for conversion disorder.

Science.gov (United States)

Armagan, E; Almacıoglu, M L; Yakut, T; Köse, A; Karkucak, M; Köksal, O; Görükmez, O

2013-03-19

Alterations in catechol-O-methyltransferase (COMT) activity are involved in various types of neurological disorders. We examined a possible association between the COMT Val158Met polymorphism and conversion disorder in a study of 48 patients with conversion disorder and 48 control patients. In the conversion disorder group, 31 patients were Val/Met heterozygotes, 15 patients were Val/Val homozygotes and 2 patients were Met/Met homozygotes. In the control group, 32 patients were Val/Met heterozygotes and 16 patients were Val/Val homozygotes. There was no significant difference between the groups. We conclude that the COMT Val158Met genotype is quite common in Turkey and that it is not a risk factor for conversion disorder in the Turkish population.

Remote Sensing of Volcanic ASH at the Met Office

Directory of Open Access Journals (Sweden)

Marenco F.

2016-01-01

Full Text Available The eruption of Eyjafjallajökull in 2010 has triggered the rapid development of volcanic ash remote sensing activities at the Met Office. Volcanic ash qualitative and quantitative mapping have been achieved using lidar on board the Facility for Airborne Atmospheric Measurements (FAAM research aircraft, and using improved satellite retrieval algorithms. After the eruption, a new aircraft facility, the Met Office Civil Contingencies Aircraft (MOCCA, has been set up to enable a rapid response, and a network of ground-based remote sensing sites with lidars and sunphotometers is currently being developed. Thanks to these efforts, the United Kingdom (UK will be much better equipped to deal with such a crisis, should it happen in the future.

Estimation of METs by Accelerometers while Walking and Running

Science.gov (United States)

Kurihara, Yosuke; Watanabe, Kajiro; Yoneyama, Mitsuru

It is quite important for Japan to maintain or promote the health condition of elderly citizens. Given the circumstances, the Ministry of Health, Labour and Welfare has established the standards for the activities and exercises for promoting the health, and quantitatively determined the exercise intensity on 107 items of activities. This exercise intensity, however, requires recording the type and the duration of the activity to be calculated. In this paper, the exercise intensities are surmised using 3D accelerometer while the subjects are walking and running. As the result, the exercise intensities were surmised to be within the root mean square error of 1.2[METs] for walking and 3.2[METs] for running respectively.

Operational Use of OGC Web Services at the Met Office

Science.gov (United States)

Wright, Bruce

2010-05-01

The Met Office has adopted the Service-Orientated Architecture paradigm to deliver services to a range of customers through Rich Internet Applications (RIAs). The approach uses standard Open Geospatial Consortium (OGC) web services to provide information to web-based applications through a range of generic data services. "Invent", the Met Office beta site, is used to showcase Met Office future plans for presenting web-based weather forecasts, product and information to the public. This currently hosts a freely accessible Weather Map Viewer, written in JavaScript, which accesses a Web Map Service (WMS), to deliver innovative web-based visualizations of weather and its potential impacts to the public. The intention is to engage the public in the development of new web-based services that more accurately meet their needs. As the service is intended for public use within the UK, it has been designed to support a user base of 5 million, the analysed level of UK web traffic reaching the Met Office's public weather information site. The required scalability has been realised through the use of multi-tier tile caching: - WMS requests are made for 256x256 tiles for fixed areas and zoom levels; - a Tile Cache, developed in house, efficiently serves tiles on demand, managing WMS request for the new tiles; - Edge Servers, externally hosted by Akamai, provide a highly scalable (UK-centric) service for pre-cached tiles, passing new requests to the Tile Cache; - the Invent Weather Map Viewer uses the Google Maps API to request tiles from Edge Servers. (We would expect to make use of the Web Map Tiling Service, when it becomes an OGC standard.) The Met Office delivers specialist commercial products to market sectors such as transport, utilities and defence, which exploit a Web Feature Service (WFS) for data relating forecasts and observations to specific geographic features, and a Web Coverage Service (WCS) for sub-selections of gridded data. These are locally rendered as maps or

Regulation of HGF and c-MET Interaction in Normal Ovary and Ovarian Cancer.

Science.gov (United States)

Kwon, Youngjoo; Godwin, Andrew K

2017-04-01

Binding of hepatocyte growth factor (HGF) to the c-MET receptor has mitogenic, motogenic, and morphogenic effects on cells. The versatile biological effects of HGF and c-MET interactions make them important contributors to the development of malignant tumors. We and others have demonstrated a therapeutic value in targeting the interaction of c-MET and HGF in epithelial ovarian cancer (EOC). However, both HGF and c-MET are expressed in the normal ovary as well. Therefore, it is important to understand the differences in mechanisms that control HGF signaling activation and its functional role in the normal ovary and EOC. In the normal ovary, HGF signaling may be under hormonal regulation. During ovulation, HGF-converting proteases are secreted and the subsequent activation of HGF signaling enhances the proliferation of ovarian surface epithelium in order to replenish the area damaged due to expulsion of the ovum. In contrast, EOC cells that exhibit epithelial characteristics constitutively express both c-MET and HGF-converting proteases such as urokinase-type plasminogen activator. In EOC, mechanisms to control the activation of HGF signaling are absent since HGF is provided locally from the tissue microenvironment as well as remotely throughout the body. Potential incessant HGF signaling in EOC may lead to an increase in proliferation, invasion through the stroma, and migration to other tissues of cancer cells. Therefore, targeting the interaction of c-MET and HGF would be beneficial in treating EOC.

The c-Met Inhibitor MSC2156119J Effectively Inhibits Tumor Growth in Liver Cancer Models

Energy Technology Data Exchange (ETDEWEB)

Bladt, Friedhelm, E-mail: Friedhelm.Bladt@merckgroup.com; Friese-Hamim, Manja; Ihling, Christian; Wilm, Claudia; Blaukat, Andree [EMD Serono, and Merck Serono Research and Development, Merck KGaA, Darmstadt 64293 (Germany)

2014-08-19

The mesenchymal-epithelial transition factor (c-Met) is a receptor tyrosine kinase with hepatocyte growth factor (HGF) as its only high-affinity ligand. Aberrant activation of c-Met is associated with many human malignancies, including hepatocellular carcinoma (HCC). We investigated the in vivo antitumor and antimetastatic efficacy of the c-Met inhibitor MSC2156119J (EMD 1214063) in patient-derived tumor explants. BALB/c nude mice were inoculated with MHCC97H cells or with tumor fragments of 10 patient-derived primary liver cancer explants selected according to c-Met/HGF expression levels. MSC2156119J (10, 30, and 100 mg/kg) and sorafenib (50 mg/kg) were administered orally as single-agent treatment or in combination, with vehicle as control. Tumor response, metastases formation, and alpha fetoprotein (AFP) levels were measured. MSC2156119J inhibited tumor growth and induced complete regression in mice bearing subcutaneous and orthotopic MHCC97H tumors. AFP levels were undetectable after 5 weeks of MSC2156119J treatment, and the number of metastatic lung foci was reduced. Primary liver explant models with strong c-Met/HGF activation showed increased responsiveness to MSC2156119J, with MSC2156119J showing similar or superior activity to sorafenib. Tumors characterized by low c-Met expression were less sensitive to MSC2156119J. MSC2156119J was better tolerated than sorafenib, and combination therapy did not improve efficacy. These findings indicate that selective c-Met/HGF inhibition with MSC2156119J is associated with marked regression of c-Met high-expressing tumors, supporting its clinical development as an antitumor treatment for HCC patients with active c-Met signaling.

Evangelisch Commando, onze omgamg met de buitenkerkelijke ...

African Journals Online (AJOL)

Test

Of J. en E. dus interkerklik is, bly 'n vraag! Die gedeelte oor die „Oorzaken van buitenkerklijkheid is prikkelend en interessant. Die vraag is net of dit nie nog dieper gesoek moet word, nl. in die herontwaking van die Heidendom wat sig sins die Renaissance hardnekkig deur sit met die outonomie van die mens in die sentrum.

University Programme Preferences of High School Science Students in Singapore and Reasons that Matter in their Preferences: A Rasch analysis

Science.gov (United States)

Oon, Pey-Tee; Subramaniam, R.

2015-01-01

This study explored an under-researched area in science education-the university programmes preferred by high school students who take physical science subjects and the reasons that matter in their preferences. A total of 1,071 upper secondary and pre-university students in Singapore, who take physical science subjects among their range of subjects, participated in this study. A survey method was adopted and the Rasch model was used to analyse the data. Overall, Business Studies was ranked as the predominant choice; nonetheless, scientific programmes such as Science, Engineering, and Mathematics are generally still well liked by the students. When gender differences were examined, we found that students largely followed gender-typical programme preferences, in which males tend to incline towards Engineering while females tend to incline towards Arts and Social Sciences. Students prefer a university programme based on their individual interest and ability, with career aspiration and remuneration coming next. Interestingly, females place greater emphasis on career aspiration than males. Some implications of the study are discussed.

The MET/AXL/FGFR Inhibitor S49076 Impairs Aurora B Activity and Improves the Antitumor Efficacy of Radiotherapy.

Science.gov (United States)

Clémenson, Céline; Chargari, Cyrus; Liu, Winchygn; Mondini, Michele; Ferté, Charles; Burbridge, Mike F; Cattan, Valérie; Jacquet-Bescond, Anne; Deutsch, Eric

2017-10-01

Several therapeutic agents targeting HGF/MET signaling are under clinical development as single agents or in combination, notably with anti-EGFR therapies in non-small cell lung cancer (NSCLC). However, despite increasing data supporting a link between MET, irradiation, and cancer progression, no data regarding the combination of MET-targeting agents and radiotherapy are available from the clinic. S49076 is an oral ATP-competitive inhibitor of MET, AXL, and FGFR1-3 receptors that is currently in phase I/II clinical trials in combination with gefitinib in NSCLC patients whose tumors show resistance to EGFR inhibitors. Here, we studied the impact of S49076 on MET signaling, cell proliferation, and clonogenic survival in MET-dependent (GTL16 and U87-MG) and MET-independent (H441, H460, and A549) cells. Our data show that S49076 exerts its cytotoxic activity at low doses on MET-dependent cells through MET inhibition, whereas it inhibits growth of MET-independent cells at higher but clinically relevant doses by targeting Aurora B. Furthermore, we found that S49076 improves the antitumor efficacy of radiotherapy in both MET-dependent and MET-independent cell lines in vitro and in subcutaneous and orthotopic tumor models in vivo In conclusion, our study demonstrates that S49076 has dual antitumor activity and can be used in combination with radiotherapy for the treatment of both MET-dependent and MET-independent tumors. These results support the evaluation of combined treatment of S49076 with radiation in clinical trials without patient selection based on the tumor MET dependency status. Mol Cancer Ther; 16(10); 2107-19. ©2017 AACR . ©2017 American Association for Cancer Research.

Reactions of Met-Cars

International Nuclear Information System (INIS)

Castleman, A.W. Jr.; Guo, B.C.

1993-01-01

A new class of metal-carbon complexes, termed metallo-carbohedrenes (Met-Cars), have been discovered to form in a plasma reactor in which early transition metals are vaporized into a stream carrying small hydrocarbon molecules. The initial discovery involved the species Ti 8 c 12 + , while subsequent studies revealed the stability of the anion and, most importantly, the neutral species. Subsequent investigations show that similar molecules, predicted to have a pentagonal dodecahedral structure, can also be formed with vanadium, hafnium, and zirconium. In the case of the latter, more recent investigations have displaced an interesting growth pattern. In particular, pentagonal dodecahedrons with dangling carbon atoms can undergo further growth, adding at least a second and third cage. The latest results on the properties and reactivities of these new cage-like molecular clusters will be discussed

The MetLife Survey of the American Teacher: Challenges for School Leadership

Science.gov (United States)

MetLife, Inc., 2013

2013-01-01

"The MetLife Survey of the American Teacher: Challenges for School Leadership" (2012) was conducted by Harris Interactive and is the twenty-ninth in a series sponsored annually by MetLife since 1984 to give voice to those closest to the classroom. This report examines the views of teachers and principals on the responsibilities and challenges…

Oxidative stress inactivates cobalamin-independent methionine synthase (MetE in Escherichia coli.

Directory of Open Access Journals (Sweden)

Elise R Hondorp

2004-11-01

Full Text Available In nature, Escherichia coli are exposed to harsh and non-ideal growth environments-nutrients may be limiting, and cells are often challenged by oxidative stress. For E. coli cells confronting these realities, there appears to be a link between oxidative stress, methionine availability, and the enzyme that catalyzes the final step of methionine biosynthesis, cobalamin-independent methionine synthase (MetE. We found that E. coli cells subjected to transient oxidative stress during growth in minimal medium develop a methionine auxotrophy, which can be traced to an effect on MetE. Further experiments demonstrated that the purified enzyme is inactivated by oxidized glutathione (GSSG at a rate that correlates with protein oxidation. The unique site of oxidation was identified by selectively cleaving N-terminally to each reduced cysteine and analyzing the results by liquid chromatography mass spectrometry. Stoichiometric glutathionylation of MetE by GSSG occurs at cysteine 645, which is strategically located at the entrance to the active site. Direct evidence of MetE oxidation in vivo was obtained from thiol-trapping experiments in two different E. coli strains that contain highly oxidizing cytoplasmic environments. Moreover, MetE is completely oxidized in wild-type E. coli treated with the thiol-oxidizing agent diamide; reduced enzyme reappears just prior to the cells resuming normal growth. We argue that for E. coli experiencing oxidizing conditions in minimal medium, MetE is readily inactivated, resulting in cellular methionine limitation. Glutathionylation of the protein provides a strategy to modulate in vivo activity of the enzyme while protecting the active site from further damage, in an easily reversible manner. While glutathionylation of proteins is a fairly common mode of redox regulation in eukaryotes, very few proteins in E. coli are known to be modified in this manner. Our results are complementary to the independent findings of Leichert

Pasarela metálica excéntrica suspendida y apoyada en un arco metálico en Orense, España

Directory of Open Access Journals (Sweden)

Besiga Díaz-Blanco, Julio

2007-12-01

Full Text Available The article explains the design and project of a steel footbridge, suspended and supported by an eccentric arc, situated in Orense. The footbridge, known as “Bellour”, has a main span of 20 meters, with a leaned steel eccentric arc that supports the deck. The deck was designed with a uniform slope of 8%, due the difference of level between each end. It is suspended from the arc in the Orense side and supported in the other boarder, because of the headway limitations. The deck is 2,80 meters wide. The cross section is composed of a steel eccentric tube with steel cantilever beams, of variable depth, and is joined at the other edge to a small steel tube. The pedestrian zone is narrower than the board, leaving individual empty spaces at both sides, and is constituted by a structural concrete slab of 7 centimeters thick and 2 meters wide, linked to the deck top sheet, with a steel profiles. The board was designed with a structural skeleton, spine shaped, suspended or supported from the arc, and it´s joined to the skin, a rough concrete surface that avoids frost and slides due to the rain.En este artículo se expone el diseño de una pasarela metálica excéntrica suspendida y apoyada en un arco metálico situada en la ciudad de Orense. La pasarela, conocida por «Bellour», tiene un único vano de 20 metros de luz, soportado excéntricamente por un arco metálico inclinado. Las cotas de inicio y fin de la pasarela obligaron a diseñar un tablero inclinado que está suspendido del arco en el lado Orense y apoyado en el otro extremo al permitirlo el gálibo de la carretera. La sección transversal del tablero está formada por un tubo excéntrico del que parten unas ménsulas metálicas de canto variable, unidas en su otro extremo por otro tubo más pequeño. El pavimento de la pasarela, que es más estrecho que el propio tablero, dejando sendos espacios vacíos a ambos lados, está formado por una losa de hormigón armado conectada a

Evaluatie van individuele happy games op de iPad voor mensen met dementie

NARCIS (Netherlands)

Dr. J.H. Groenewoud; Dr. J. de Lange

2014-01-01

Er is veel belangstelling voor de kwaliteit van zorg voor mensen met dementie. Ook hun kwaliteit van leven krijgt steeds meer aandacht. Een zinvolle en plezierige dagbesteding hoort daarbij. Zorgprofessionals willen mensen met dementie graag ondersteunen bij het doen van activiteiten. Het huidige

The COMT val158met polymorphism and brain morphometry in healthy young adults

NARCIS (Netherlands)

Zinkstok, Janneke; Schmitz, Nicole; van Amelsvoort, Therese; de Win, Maartje; van den Brink, Wim; Baas, Frank; Linszen, Don

2006-01-01

Catechol-O-methyltransferase (COMT) is the most important mechanism for dopamine degradation in the prefrontal cortex and contains a functional polymorphism (val(158)met) influencing enzyme activity. The low-activity met allele has been associated with better performance on cognitive tasks relying

Effects of the BDNF Val66Met polymorphism on neural responses to facial emotion.

Science.gov (United States)

Mukherjee, Prerona; Whalley, Heather C; McKirdy, James W; McIntosh, Andrew M; Johnstone, Eve C; Lawrie, Stephen M; Hall, Jeremy

2011-03-31

The brain derived neurotrophic factor (BDNF) Val66Met polymorphism has been associated with affective disorders, but its role in emotion processing has not been fully established. Due to the clinically heterogeneous nature of these disorders, studying the effect of genetic variation in the BDNF gene on a common attribute such as fear processing may elucidate how the BDNF Val66Met polymorphism impacts brain function. Here we use functional magnetic resonance imaging examine the effect of the BDNF Val66Met genotype on neural activity for fear processing. Forty healthy participants performed an implicit fear task during scanning, where subjects made gender judgments from facial images with neutral or fearful emotion. Subjects were tested for facial emotion recognition post-scan. Functional connectivity was investigated using psycho-physiological interactions. Subjects were genotyped for the BDNF Val66Met polymorphism and the measures compared between genotype groups. Met carriers showed overactivation in the anterior cingulate cortex (ACC), brainstem and insula bilaterally for fear processing, along with reduced functional connectivity from the ACC to the left hippocampus, and impaired fear recognition ability. The results show that during fear processing, Met allele carriers show an increased neural response in regions previously implicated in mediating autonomic arousal. Further, the Met carriers show decreased functional connectivity with the hippocampus, which may reflect differential retrieval of emotional associations. Together, these effects show significant differences in the neural substrate for fear processing with genetic variation in BDNF. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Advanced CerMet ceramic composites for medical applications.

Science.gov (United States)

Dittmer, Robert; Schaefer, Christian M; Fischer, Jean-Francois; Hausch, Ulrich; Troetzschel, Jens; Specht, Heiko

2017-11-01

Implantable active devices such as pacemakers are facing rigorous requirements. Because they reside within the body for years, materials applied in this surrounding must exhibit biocompatibility and extraordinary reliability. They also have to provide a number of functional properties. In this work we present a method that enables the realization of a highly complex profile of properties by means of a dual composite approach. Using multilayer technology, an electrical conductor is embedded into a ceramic matrix, thus, creating conductive paths that are insulated from each other. In addition to this macroscopically hybrid architecture, this approach features a second composite aspect: the conductor is not composed of a single metallic phase, but is a ceramic-metal mixture. Owing to its interpenetrating microstructure, this CerMet allows for a strong and hermetic integration of the conductor into the ceramic matrix otherwise impossible due to mismatch in thermal expansion. In fact, the CerMet ceramic composite exhibits a higher strength than the pure ceramic as revealed by a three-point bending test study. At the same time, the CerMet offers high and virtually metal-like conductor properties, enabling a down-scaling of the conductive paths to 150µm diameter and smaller. Furthermore, the described composite is biocompatible, non-magnetic, and chemically inert, which is vital for the application in active, implantable, medical devices. Beside the general fabrication route, we present the microstructural, functional, and mechanical properties of this newly developed class of dual composites. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phase I dose-escalation study of the c-Met tyrosine kinase inhibitor SAR125844 in Asian patients with advanced solid tumors, including patients with MET-amplified gastric cancer.

Science.gov (United States)

Shitara, Kohei; Kim, Tae Min; Yokota, Tomoya; Goto, Masahiro; Satoh, Taroh; Ahn, Jin-Hee; Kim, Hyo Song; Assadourian, Sylvie; Gomez, Corinne; Harnois, Marzia; Hamauchi, Satoshi; Kudo, Toshihiro; Doi, Toshihido; Bang, Yung-Jue

2017-10-03

SAR125844 is a potent and selective inhibitor of the c-Met kinase receptor. This was an open-label, phase I, multicenter, dose-escalation, and dose-expansion trial of SAR125844 in Asian patients with solid tumors, a subgroup of whom had gastric cancer and MET amplification (NCT01657214). SAR125844 was administered by intravenous infusion (260-570 mg/m 2 ) on days 1, 8, 15, and 22 of each 28-day cycle. Objectives were to determine the maximum tolerated dose (MTD) and to evaluate SAR125844 safety and pharmacokinetic profile. Antitumor activity was also assessed. Of 38 patients enrolled (median age 64.0 years), 22 had gastric cancer, including 14 with MET amplification. In the dose-escalation cohort ( N = 19; unselected population, including three patients with MET -amplification [two with gastric cancer and one with lung cancer]), the MTD was not reached, and the recommended dose was established at 570 mg/m 2 . Most frequent treatment-emergent adverse events (AEs) were nausea (36.8%), vomiting (34.2%), decreased appetite (28.9%), and fatigue or asthenia, constipation, and abdominal pains (each 21.1%); none appeared to be dose-dependent. Grade ≥ 3 AEs were observed in 39.5% of patients and considered drug-related in 7.9%. SAR125844 exposure increased slightly more than expected by dose proportionality; dose had no significant effect on clearance. No objective responses were observed in the dose-escalation cohort, with seven patients (three gastric cancer, two colorectal cancer, one breast cancer, and one with cancer of unknown primary origin) having stable disease. Modest antitumor activity was observed at 570 mg/m 2 in the dose-expansion cohort, comprising patients with MET -amplified tumors ( N = 19). Two gastric cancer patients had partial responses, seven patients had stable disease (six gastric cancer and one kidney cancer), and 10 patients had progressive disease. Single-agent SAR125844 administered up to 570 mg/m 2 has acceptable tolerability and modest

Discovery of imidazopyridine derivatives as novel c-Met kinase inhibitors: Synthesis, SAR study, and biological activity.

Science.gov (United States)

Yang, Yifei; Zhang, Yuan; Yang, LingYun; Zhao, Leilei; Si, Lianghui; Zhang, Huibin; Liu, Qingsong; Zhou, Jinpei

2017-02-01

Receptor tyrosine kinase c-Met acts as an alternative angiogenic pathway in the process and contents of cancers. A series of imidazopyridine derivatives were designed and synthesized according to the established docking studies as possible c-Met inhibitors. Most of these imidazopyridine derivatives displayed nanomolar potency against c-Met in both biochemical enzymatic screens and cellular pharmacology studies. Especially, compound 7g exhibited the most inhibitory activity against c-Met with IC 50 of 53.4nM and 253nM in enzymatic and cellular level, respectively. Following that, the compound 7g was docked into the protein of c-Met and the structure-activity relationship was analyzed in detail. These findings indicated that the novel imidazopyridine derivative compound 7g was a potential c-Met inhibitor deserving further investigation for cancer treatment. Copyright © 2016. Published by Elsevier Inc.

Comportamento experimental de diferentes tipos de conectores metálicos

OpenAIRE

Valente, Isabel B.

2016-01-01

A realização de estruturas mistas de aço e betão requer o funcionamento conjunto destes dois materiais. A ligação entre eles é conseguida com a utilização de conectores metálicos. Neste âmbito, tem sido realizada uma considerável quantidade de estudos que abordam o comportamento de diversos tipos de conectores metálicos. O desejo de obter um comportamento óptimo com custos mínimos motivou o desenvolvimento de várias soluções. Neste artigo, procura-se descrever o comportamento de diferente...

A Meteorological Distribution System for High Resolution Terrestrial Modeling (MicroMet)

Science.gov (United States)

Liston, G. E.; Elder, K.

2004-12-01

Spatially distributed terrestrial models generally require atmospheric forcing data on horizontal grids that are of higher resolution than available meteorological data. Furthermore, the meteorological data collected may not necessarily represent the area of interest's meteorological variability. To address these deficiencies, computationally efficient and physically realistic methods must be developed to take available meteorological data sets (e.g., meteorological tower observations) and generate high-resolution atmospheric-forcing distributions. This poster describes MicroMet, a quasi-physically-based, but simple meteorological distribution model designed to produce high-resolution (e.g., 5-m to 1-km horizontal grid increments) meteorological data distributions required to run spatially distributed terrestrial models over a wide variety of landscapes. The model produces distributions of the seven fundamental atmospheric forcing variables required to run most terrestrial models: air temperature, relative humidity, wind speed, wind direction, incoming solar radiation, incoming longwave radiation, and precipitation. MicroMet includes a preprocessor that analyzes meteorological station data and identifies and repairs potential data deficiencies. The model uses known relationships between meteorological variables and the surrounding area (primarily topography) to distribute those variables over any given landscape. MicroMet performs two kinds of adjustments to available meteorological data: 1) when there are data at more than one location, at a given time, the data are spatially interpolated over the domain using a Barnes objective analysis scheme, and 2) physical sub-models are applied to each MicroMet variable to improve its realism at a given point in space and time with respect to the terrain. The three, 25-km by 25-km, Cold Land Processes Experiment (CLPX) mesoscale study areas (MSAs: Fraser, North Park, and Rabbit Ears) will be used as example MicroMet

Testing ATLAS Z+MET excess with LHC run 2

International Nuclear Information System (INIS)

Lu, Xiaochuan; Terada, Takahiro

2016-05-01

The ATLAS collaboration reported a 3σ excess in the search of events containing on-Z dilepton, jets, and large missing momentum (MET) in the 8 TeV LHC run. Motivated by this excess, many models of new physics have been proposed. Recently, the ATLAS and CMS collaborations reported new results for similar Z+MET channels in the 13 TeV run. In this paper, we comprehensively discuss the consistency between the proposed models and the LHC results of Run 1 and Run 2. We find that in models with heavy gluino production, there is generically some tension between the 8 TeV and 13 TeV results. On the other hand, models with light squark production provide relatively better fitting to both results.

Beoordeling gezondheidsrisico's door sporten op kunstgrasvelden met rubbergranulaat

NARCIS (Netherlands)

Oomen AG; de Groot GM; CPV; M&V

2016-01-01

Uit nieuw onderzoek van het RIVM blijkt dat het risico voor de gezondheid van sporten op kunstgrasvelden die zijn ingestrooid met rubbergranulaat, praktisch verwaarloosbaar is. Dat betekent dat het verantwoord is om op deze velden te sporten. Aanleiding voor het onderzoek is de maatschappelijke

Aan de slag met honors : praktijklessen uit Europa

NARCIS (Netherlands)

Wolfensberger, Marca; Hogenstijn, Maarten

2015-01-01

In de brochure ‘Aan de slag met honors’ worden onderzoeksresultaten van het onderzoeksproject Honors in Europe hertaald naar tips voor succesvol en inspirerend honorsonderwijs. De brochure is grotendeels gebaseerd op het boek Talent Development in European Higher Education – Honors programs in the

Praktijkervaringen met de Venlow energy kas 2010-2012

NARCIS (Netherlands)

Kempkes, F.L.K.; Janse, J.

2013-01-01

NL De energiebesparing bij het nieuwe telen werd tot nu toe altijd bereikt door meer schermen te gebruiken. Een alternatief is toepassing van isolatieglas dat door de komst van coatings zoals Anti Refl ectie een vergelijkbare transmissie heeft als standaard enkel glas. Met een aangepast

MET-2-Dependent H3K9 Methylation Suppresses Transgenerational Small RNA Inheritance.

Science.gov (United States)

Lev, Itamar; Seroussi, Uri; Gingold, Hila; Bril, Roberta; Anava, Sarit; Rechavi, Oded

2017-04-24

In C. elegans, alterations to chromatin produce transgenerational effects, such as inherited increase in lifespan and gradual loss of fertility. Inheritance of histone modifications can be induced by double-stranded RNA-derived heritable small RNAs. Here, we show that the mortal germline phenotype, which is typical of met-2 mutants, defective in H3K9 methylation, depends on HRDE-1, an argonaute that carries small RNAs across generations, and is accompanied by accumulated transgenerational misexpression of heritable small RNAs. We discovered that MET-2 inhibits small RNA inheritance, and, as a consequence, induction of RNAi in met-2 mutants leads to permanent RNAi responses that do not terminate even after more than 30 generations. We found that potentiation of heritable RNAi in met-2 animals results from global hyperactivation of the small RNA inheritance machinery. Thus, changes in histone modifications can give rise to drastic transgenerational epigenetic effects, by controlling the overall potency of small RNA inheritance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Subtiel verleiden met nudging : Verhogen van enquêterespons

NARCIS (Netherlands)

V. Versluis; dr. A.F. de Wild

2015-01-01

De nonrespons op enquêtes onder studenten is vaak hoog, waardoor verkregen informatie niet altijd betrouwbaar en valide is. Met nudges, subtiele interventies die gebaseerd zijn op inzichten uit de psychologie en sociologie, kan de respons op enquêtes aanzienlijk worden verhoogd. Bij de uitrol van

Randvoorwaarden ontwerp happy games voor ouderen met dementie

NARCIS (Netherlands)

Dr. A.L. Cordia

2014-01-01

Deze publicatie is in twee fasen tot stand gekomen tijdens het In Touch onderzoek. De eerste fase had als doel de randvoorwaarden te bepalen voor het ontwerpen van drie nieuwe iPad spellen voor ouderen met dementie en betrof een beperkt literatuuronderzoek op gerelateerde onderwerpen, daar

Vers bloed voor spinazie (interview met C. Kik)

NARCIS (Netherlands)

Nijland, R.; Kik, C.

2011-01-01

Chris Kik van het Centrum voor Genetische Bronnen Nederland (CGN) keerde afgelopen weekend terug van een eenmansexpeditie door Azerbeidzjan, Georgië en Armenië. Resultaat van de reis: een koffer volgepropt met 53 witte linnen zakjes zaad van wilde en lokaal geteelde spinazie. Dat materiaal gaat

BDNF VAL66MET Polymorphism Elevates the Risk of Bladder Cancer via MiRNA-146b in Micro-Vehicles

Directory of Open Access Journals (Sweden)

Cong Li

2018-01-01

Full Text Available Background/Aims: Emerging studies on brain-derived neurotrophic factor (BDNF have shown that might be novel biomarkers and therapeutic targets for cancer. We explore the role of BDNF in the tumorigenesis of bladder cancer and the underlying molecular mechanism. Methods: 368 patients with diagnosed bladder cancer and 352 healthy controls were enrolled to evaluate the association of BDNF and the miR-146b. Bioinformatics algorithm analysis and luciferase assay were performed to identify the target genes of miR-146b. Real-time PCR and western-blot were carried out to validate the relationship between miR-146b and CRK. MTT assay and FACS were used to evaluated the proliferation and apoptosis of cancer cells. MVs were isolated and transfect into the culture cells to confirm the above observation. Results: The clinical study shows that BDNF Met/Met was significantly associated with the risk of bladder cancer. In addition, comparing with Val/Val and Val/Met, Met/Met has lower miR-146b level. Luciferase assay shows that BDNF Val/Val is apparently enhanced miR-146b promoter-luciferase, but not BDNF Met/Met. Based on luciferase assay, CRK is a direct target gene of miR-146b. MiR-146b mimics significantly inhibited the expression of CRK and activation of AKT level. The expression of CRK and the activation of AKT (p-AKT were significantly inhibited by MV-BDNF Val/Val-miR-146b or MV-BDNF Val/Met-miR-146b, but not MV-BDNF Met/Met-miR-146b. MV-BDNF Val/Val-miR-146b or Val/Met-miR-146b obviously inhibited cell proliferation, which eliminated by CRK. Meanwhile, with MV-BDNF Met/Met-miR-146b or Met/Met-miR-146b+CRK did not affect the proliferation. MV-BDNF Val/Val-miR-146b or Val/Met-miR-146b enhanced cell apoptosis, which could be eliminated by CRK. Meanwhile, MV-BDNF Met/Met-miR-146b or Met/Met-miR-146b+CRK did not promote apoptosis. Conclusion: BDNF VAL66MET polymorphism is associated with miR-146b and its target gene CRK. MiR-146b and CRK mediated BDNF VAL66

Samen leven met ME/CVS : Een onderzoek naar de rol van partnersteun en ziekterepresentaties bij coping met en adaptatie aan ME/CVS.

NARCIS (Netherlands)

Marleen Hofman, [No Value

2013-01-01

Achtergrond: Het chronisch vermoeidheidssyndroom (CVS) is een chronische ziekte die wordt gekenmerkt door ernstige vermoeidheid die vaak gepaard gaat met reumatische, infectieuze en neuropsychiatrische klachten. Het is een ernstig invaliderende aandoening waar tot nog toe geen genezende behandeling

34 CFR 692.101 - What requirements must be met by a State partnership?

Science.gov (United States)

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false What requirements must be met by a State partnership...) OFFICE OF POSTSECONDARY EDUCATION, DEPARTMENT OF EDUCATION LEVERAGING EDUCATIONAL ASSISTANCE PARTNERSHIP... What requirements must be met by a State partnership? (a) State. A State that is receiving an allotment...

The functional BDNF Val66Met polymorphism affects functions of pre-attentive visual sensory memory processes.

Science.gov (United States)

Beste, Christian; Schneider, Daniel; Epplen, Jörg T; Arning, Larissa

2011-01-01

The brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, is involved in nerve growth and survival. Especially, a single nucleotide polymorphism (SNP) in the BDNF gene, Val66Met, has gained a lot of attention, because of its effect on activity-dependent BDNF secretion and its link to impaired memory processes. We hypothesize that the BDNF Val66Met polymorphism may have modulatory effects on the visual sensory (iconic) memory performance. Two hundred and eleven healthy German students (106 female and 105 male) were included in the data analysis. Since BDNF is also discussed to be involved in the pathogenesis of depression, we additionally tested for possible interactions with depressive mood. The BDNF Val66Met polymorphism significantly influenced iconic-memory performance, with the combined Val/Met-Met/Met genotype group revealing less time stability of information stored in iconic memory than the Val/Val group. Furthermore, this stability was positively correlated with depressive mood exclusively in the Val/Val genotype group. Thus, these results show that the BDNF Val66Met polymorphism has an effect on pre-attentive visual sensory memory processes. Copyright © 2010 Elsevier Ltd. All rights reserved.