2,197 research outputs found

    Full-field pulsed magneto-photoelasticity – Experimental Implementation

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    This paper contains a description of the experimental procedure employed when using a pulsed-magneto-polariscope (PMP) and some initial full-field through-thickness measurements of the stress distribution present in samples containing 3D stresses. The instrument uses the theory of magneto-photoelasticity (MPE), which is an experimental stress analysis technique that involves the application of a magnetic field to a birefringent model within a polariscope. MPE was developed for through-thickness stress measurement where the integrated through-thickness birefringent measurement disguises the actual stress distribution. MPE is mainly used in toughened glass where the through-thickness distribution can reduce its overall strength and so its determination is important. To date MPE has been a single-point 2D through-thickness measurement and the analysis time is prohibitive for the investigation of an area which may contain high localised stresses. The pulsed-magneto-polariscope (PMP) has been designed to enable the application of full-field 3D MPE [ ]. Using a proof-of concept PMP several experimental measurements were made, these were promising and demonstrate the potential of the new instrument. Further development of this technique presents several exciting possibilities including a tool for the measurement of the distribution of principal stress difference seen in a general 3D model

    Too anxious to control : the relation between math anxiety and inhibitory control processes

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    Based on the attentional control theory, math anxiety has been explained in terms of impaired inhibition, a key cognitive control function associated with the central executive. Inhibition allows us to suppress task-irrelevant interference when needed. Inspired by the Dual Mechanisms of Control theory, the current study aimed to disentangle the effect of math anxiety on two cognitive control aspects that can be identified in inhibition. Reactive control occurs after interference is detected and is mostly used in a context where interference is scarce. Proactive control is used to prevent and anticipate interference before it occurs and is preferred in contexts where interference is frequent. We used an arrow flanker task where the proportion of interference was manipulated to stimulate the use of a reactive or proactive control strategy. The results showed that response times on trials containing interference increased with math anxiety, but only in a reactive task context. In a proactive task context response times were not influenced by math anxiety. Our results suggest that math anxiety impairs reactive control. We hypothesize that this finding can be explained by a higher state of distractibility, triggered both by the reactive context and by math anxiety

    The importance of transport model uncertainties for the estimation of CO2 sources and sinks using satellite measurements

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    This study presents a synthetic model intercomparison to investigate the importance of transport model errors for estimating the sources and sinks of CO2 using satellite measurements. The experiments were designed for testing the potential performance of the proposed CO2 lidar A-SCOPE, but also apply to other space borne missions that monitor total column CO2. The participating transport models IFS, LMDZ, TM3, and TM5 were run in forward and inverse mode using common a priori CO2 fluxes and initial concentrations. Forward simulations of column averaged CO2 (xCO2) mixing ratios vary between the models by s=0.5 ppm over the continents and s=0.27 ppm over the oceans. Despite the fact that the models agree on average on the sub-ppm level, these modest differences nevertheless lead to significant discrepancies in the inverted fluxes of 0.1 PgC/yr per 106 km2 over land and 0.03 PgC/yr per 106 km2 over the ocean. These transport model induced flux uncertainties exceed the target requirement that was formulated for the A-SCOPE mission of 0.02 PgC/yr per 106 km2, and could also limit the overall performance of other CO2 missions such as GOSAT. A variable, but overall encouraging agreement is found in comparison with FTS measurements at Park Falls, Darwin, Spitsbergen, and Bremen, although systematic differences are found exceeding the 0.5 ppm level. Because of this, our estimate of the impact of transport model uncerainty is likely to be conservative. It is concluded that to make use of the remote sensing technique for quantifying the sources and sinks of CO2 not only requires highly accurate satellite instruments, but also puts stringent requirements on the performance of atmospheric transport models. Improving the accuracy of these models should receive high priority, which calls for a closer collaboration between experts in atmospheric dynamics and tracer transpor

    Sex differences in treatment patterns for non-advanced muscle-invasive bladder cancer: a descriptive analysis of 3484 patients of the Netherlands Cancer Registry.

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    PURPOSE Bladder cancer (BC) is a common malignancy with well-established differences in incidence, clinical manifestation and outcomes between men and women. It is unknown to what extent disparities in outcomes are influenced by differences in treatment approaches. This paper describes treatment patterns among men and women with muscle-invasive BC focusing on curative treatment (radical cystectomy or trimodal therapy). METHODS A retrospective population-based cohort study was performed with data from the Netherlands Cancer Registry. All patients newly diagnosed with muscle-invasive, non-advanced BC (MIBC, cT2-4a, N0/X, M0/X) in the years 2018, 2019 and 2020 were identified. Patient and tumor characteristics and initial treatment were compared between men and women with descriptive statistics and multivariable logistic regression analyses. RESULTS A total of 3484 patients were diagnosed with non-advanced MIBC in 2018-2020 in the Netherlands, of whom 28% were women. Women had higher T-stage and more often non-urothelial histology. Among all strata of clinical T-stage, women less often received treatment with curative intent (radical cystectomy [RC] or trimodality treatment). Among RC-treated patients, women more often received neoadjuvant treatment (except for cT4a disease). After adjustment for pre-treatment factors, odds ratios were indicative of women having lower probability of receiving curative treatment and RC specifically, and higher probability to receive NAC when treated with RC then men, although not statistically significant. CONCLUSIONS Considerable differences in treatment patterns between men and women with MIBC exist. A more considerate role of the patient's sex in treatment decisions could help decrease these differences and might mitigate disparities in outcomes

    Heterofusion:Fusing genomics data of different measurement scales

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    In systems biology, it is becoming increasingly common to measure biochemical entities at different levels of the same biological system. Hence, data fusion problems are abundant in the life sciences. With the availability of a multitude of measuring techniques, one of the central problems is the heterogeneity of the data. In this paper, we discuss a specific form of heterogeneity, namely, that of measurements obtained at different measurement scales, such as binary, ordinal, interval, and ratio‐scaled variables. Three generic fusion approaches are presented of which two are new to the systems biology community. The methods are presented, put in context, and illustrated with a real‐life genomics example

    Validation and reliability of the Dutch version of the EORTC QLQ-BLM30 module for assessing the health-related quality of life of patients with muscle invasive bladder cancer

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    Background: Quality of Life (QoL) of bladder cancer patients has been largely neglected. This is partly due to the lack of well-validated QoL questionnaires. The aim of this study is to examine the structural validity, reliability (i.e., internal consistency and test-retest reliability), construct validity (i.e., divergent validity and known group validity) and responsiveness of the Dutch version of the European Organisation for Research and Treatment of Cancer QoL questionnaire for muscle invasive bladder cancer (EORTC-QLQ-BLM30). Methods: Patients with newly diagnosed muscle invasive bladder cancer (MIBC) participating in the population-based ‘Blaaskankerzorg In Beeld’ (BlaZIB) study who completed the EORTC-QLQ-BLM30 at baseline were included. BlaZIB is a Dutch nationwide population-based prospective cohort study collecting clinical data and QoL data of bladder cancer patients. QoL is assessed with a self-administered questionnaire at four points in time: 6 weeks (baseline), 6 months, 12 months and 24 months after diagnosis. Confirmatory factor analysis and multitrait scaling analysis were used to investigate and adapt the scale structure. Reliability, construct validity and responsiveness of the revised scales were evaluated. Results: Of the 1542 patients invited to participate, 650 patients (42.2%) completed the QLQ-BLM30 at baseline. The questionnaire’s scale structure was revised into seven scales and eight single items. Internal consistency and test-reliability were adequate for most scales (Cronbach’s α ≄0.70 and intraclass correlation coefficient ≄ 0.70, respectively), with the exception of the revised urostomy problem scale and abdominal bloating and flatulence scale. The questionnaire exhibited little overlap with the EORTC-QLQ-C30: all correlations were &lt; 0.40, except for the correlation between emotional function (QLQ-C30) and future worries (QLQ-BLM30). The questionnaire was able to distinguish between patient subgroups formed on the basis of physical function, but not – as hypothesized– based on stage. Changes in health due to treatment were captured by the questionnaire, indicating that the questionnaire is responsive to change. Conclusions: This study shows that the adapted scale structure of the EORTC-QLQ-BLM30 generally exhibits good measurement properties in Dutch patients, but needs to be validated in other languages and settings. Trial registration: BlaZIB, NL8106, www.trialregister.nl.</p

    Validation and reliability of the Dutch version of the EORTC QLQ-BLM30 module for assessing the health-related quality of life of patients with muscle invasive bladder cancer

    Get PDF
    Background: Quality of Life (QoL) of bladder cancer patients has been largely neglected. This is partly due to the lack of well-validated QoL questionnaires. The aim of this study is to examine the structural validity, reliability (i.e., internal consistency and test-retest reliability), construct validity (i.e., divergent validity and known group validity) and responsiveness of the Dutch version of the European Organisation for Research and Treatment of Cancer QoL questionnaire for muscle invasive bladder cancer (EORTC-QLQ-BLM30). Methods: Patients with newly diagnosed muscle invasive bladder cancer (MIBC) participating in the population-based ‘Blaaskankerzorg In Beeld’ (BlaZIB) study who completed the EORTC-QLQ-BLM30 at baseline were included. BlaZIB is a Dutch nationwide population-based prospective cohort study collecting clinical data and QoL data of bladder cancer patients. QoL is assessed with a self-administered questionnaire at four points in time: 6 weeks (baseline), 6 months, 12 months and 24 months after diagnosis. Confirmatory factor analysis and multitrait scaling analysis were used to investigate and adapt the scale structure. Reliability, construct validity and responsiveness of the revised scales were evaluated. Results: Of the 1542 patients invited to participate, 650 patients (42.2%) completed the QLQ-BLM30 at baseline. The questionnaire’s scale structure was revised into seven scales and eight single items. Internal consistency and test-reliability were adequate for most scales (Cronbach’s α ≄0.70 and intraclass correlation coefficient ≄ 0.70, respectively), with the exception of the revised urostomy problem scale and abdominal bloating and flatulence scale. The questionnaire exhibited little overlap with the EORTC-QLQ-C30: all correlations were &lt; 0.40, except for the correlation between emotional function (QLQ-C30) and future worries (QLQ-BLM30). The questionnaire was able to distinguish between patient subgroups formed on the basis of physical function, but not – as hypothesized– based on stage. Changes in health due to treatment were captured by the questionnaire, indicating that the questionnaire is responsive to change. Conclusions: This study shows that the adapted scale structure of the EORTC-QLQ-BLM30 generally exhibits good measurement properties in Dutch patients, but needs to be validated in other languages and settings. Trial registration: BlaZIB, NL8106, www.trialregister.nl.</p
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