From an evidence-based perspective, cardiopulmonary exercise testing (CPX) is a well-supported assessment technique in both the United States (US) and Europe. The combination of standard exercise testing (ET) [i.e. progressive exercise provocation in association with serial electrocardiograms (ECGs), haemodynamics, oxygen saturation, and subjective symptoms] and measurement of ventilatory gas exchange amounts to a superior method to: (i) accurately quantify cardiorespiratory fitness (CRF), (ii) delineate the physiologic system(s) underlying exercise responses, which can be applied as a means to identify the exercise-limiting pathophysiological mechanism(s) and/or performance differences, and (iii) formulate function-based prognostic stratification. Cardiopulmonary ET certainly carries an additional cost as well as competency requirements and is not an essential component of evaluation in all patient populations. However, there are several conditions of confirmed, suspected, or unknown aetiology where the data gained from this form of ET is highly valuable in terms of clinical decision making.1
Formula scoring (FS) is the use of a don't know option (DKO) with subtraction of points for wrong answers. Its effect on construct validity and reliability of progress test scores, is subject of discussion. Choosing a DKO may not only be affected by knowledge level, but also by risk taking tendency, and may thus introduce construct-irrelevant variance into the knowledge measurement. On the other hand, FS may result in more reliable test scores. To evaluate the impact of FS on construct validity and reliability of progress test scores, a progress test for radiology residents was divided into two tests of 100 parallel items (A and B). Each test had a FS and a number-right (NR) version, A-FS, B-FS, A-NR, and B-NR. Participants (337) were randomly divided into two groups. One group took test A-FS followed by B-NR, and the second group test B-FS followed by A-NR. Evidence for impaired construct validity was sought in a hierarchical regression analysis by investigating how much of the participants' FS-score variance was explained by the DKO-score, compared to the contribution of the knowledge level (NR-score), while controlling for Group, Gender, and Training length. Cronbach's alpha was used to estimate NR and FS-score reliability per year group. NR score was found to explain 27 % of the variance of FS [F(1,332) = 219.2, p < 0.0005], DKO-score, and the interaction of DKO and Gender were found to explain 8 % [F(2,330) = 41.5, p < 0.0005], and the interaction of DKO and NR 1.6 % [F(1,329) = 16.6, p < 0.0005], supporting our hypothesis that FS introduces construct-irrelevant variance into the knowledge measurement. However, NR-scores showed considerably lower reliabilities than FS-scores (mean year-test group Cronbach's alphas were 0.62 and 0.74, respectively). Decisions about FS with progress tests should be a careful trade-off between systematic and random measurement error.
Size measurement plays an essential role for micro-/nanoparticle characterization and property evaluation. Due to high costs, complex operation or resolution limit, conventional characterization techniques cannot satisfy the growing demand of routine size measurements in various industry sectors and research departments, e.g., pharmaceuticals, nanomaterials and food industry etc. Together with start-up SeeNano and other partners, we will develop a portable compact device to measure particle size based on particle-impact electrochemical sensing technology. The main task in this project is to extend the measurement range for particles with diameters ranging from 20 nm to 20 um and to validate this technology with realistic samples from various application areas. In this project a new electrode chip will be designed and fabricated. It will result in a workable prototype including new UMEs (ultra-micro electrode), showing that particle sizing can be achieved on a compact portable device with full measuring range. Following experimental testing with calibrated particles, a reliable calibration model will be built up for full range measurement. In a further step, samples from partners or potential customers will be tested on the device to evaluate the application feasibility. The results will be validated by high-resolution and mainstream sizing techniques such as scanning electron microscopy (SEM), dynamic light scattering (DLS) and Coulter counter.
Lab-on-a-Chip (LOC) devices worden op dit moment voor het overgrote deel in de wetenschap toegepast, in laboratoria met apparatuur die daar gebruikelijk is. LOC-devices hebben echter een grote potentie buiten de laboratoria, in bijvoorbeeld Point-Of-Care Testing situaties in de gezondheidszorg, en het verrichten van metingen ter plaatse t.b.v. de voedsel- en watersector. Ook in andere applicatievelden zoals forensisch recherchewerk, en environmental monitoring kunnen LOC devices een enorme impact hebben. Voorwaarde is wel dat zij hanteerbaarder, goedkoper en robuuster worden, en qua productiewijze minder gecompliceerd. De ontwikkeling van de huidige LOCs vereist een aanzienlijke investering om tot een werkend en betrouwbaar product te komen. Traditioneel wordt hierbij gebruikt gemaakt van kostbare fotolithografische technieken in combinatie met chemisch etsen in zogenoemde cleanrooms. Dit maakt de initiële drempel voor nieuwe toepassingen extreem hoog. Daarnaast is de apparatuur om deze chips aan te sluiten, aan te sturen en een meting te verrichten in veel gevallen zeer specialistisch en daardoor blijft de inzet van deze technologie beperkt tot een goed geoutilleerd lab. Met het LOC2Use project van Saxion lectoraten NanoBio en Industrial Design in samenwerking met het bedrijfsleven wordt beoogd om de LOC-technologie uit het lab te halen, door technologische toepassingen te ontwikkelen op basis van meer toegankelijke technologie. Vertrekpunt voor de toepassingen zijn de use-cases, die in samenwerking met stakeholders en MKB-partners in verschillende toepassingsgebieden worden opgesteld. Beoogd resultaat is een catalogus vol met getoetste technische oplossingen, gekoppeld aan de eisen uit de use-cases. Aan de hand van de gevonden technologische oplossingen worden een viertal illustratieve cases uitgewerkt. En worden er uit de catalogus een aantal bruikbare technologische bouwstenen geselecteerd voor rapid prototyping en kleine series microfluidic devices in een FabLab omgeving, een eerste stap in de richting van een LOC-fieldlab. Met dit project wordt LOC betaalbaar en breder toepasbaar voor het MKB.
