Search results for "Measurements"
showing 10 items of 720 documents
Capturing cognitive load management during authentic virtual reality flight training with behavioural and physiological indicators
2023
Background Cognitive load (CL) management is essential in safety-critical fields so that professionals can monitor and control their cognitive resources efficiently to perform and solve scenarios in a timely and safe manner, even in complex and unexpected circumstances. Thus, cognitive load theory (CLT) can be used to design virtual reality (VR) training programmes for professional learning in these fields. Objectives We studied CL management performance through behavioural indicators in authentic VR flight training and explored if and to what extent physiological data was associated with CL management performance. Methods The expert (n = 8) and novice pilots (n = 6) performed three approac…
Efficient design and modeling strategies for follow-up studies with time-varying covariates
2015
Epidemiological studies can often be designed in several ways, some of which may be more optimal than others. Possible designs may differ in the required resources or the ability to provide reliable answers to the questions under study. In addition, once the data are collected, the selected modeling approach may affect how efficiently the data are utilized. The purpose of this dissertation is to investigate efficient designs and analysis meth ods in follow-up studies with longitudinal measurements. A key question is how to select optimally a subcohort for a new longitudinal covariate measurement if we cannot afford to measure the entire cohort. Another key question we consider is how to determine …
Electrodeposition and characterization of Mo oxide nanostructures
2015
Template electrodeposition has been used to grow uniform arrays of molybdenum oxide nanostructures in polycarbonate membrane. Several parameters have been investigated, like electrodeposition, time and solution pH. These parameters do not influence the nature of the deposit that always consists of mixed valence molybdenum oxides, whereas the nanostructure morphology changes with pH. In particular, at low pH (2.7), nanotubes are formed, whilst arrays of nanowires are obtained above pH 5.5. This change of morphology is likely due to H2 bubbles evolution during the electrochemical deposition, particularly occurring at low pH. It was found that fast removal of H2 bubbles through vigorous stirri…
The Role of Capital Accumulation in the Evolution of Total Factor Productivity in Spain
2017
GDP growth in Spain was strong for much of the last half century, whereas the country’s productivity performance during these years has been mediocre. The reasons for this situation have frequently been analysed with the focus on labour productivity. But, as this article highlights, the evolution of capital productivity should also be taken into account when looking for explanations for poor productivity performance. This article analyses the sources of growth in the Spanish economy, in comparison with major economies, and takes into account the effects that the improvements in the measurement of inputs (labour and capital) have on TFP estimates. Once problems are identified and the role pl…
VALIDITY AND RELIABILITY OF MEASUREMENTS OF THE PARAMETERS OF SMILE AESTHETICS: A COMPARISON BETWEEN DIGITAL AND PLASTER MODELS
2020
This study aims to evaluate the validity and reliability of the TRIOS3 Color intraoral scanner (3Shape A/S, Copenhagen, Denmark) and its associated Ortho Analyzer™ software in measuring parameters of smile aesthetics compared with measurements on plaster casts. The study sample comprised plaster casts and digital models obtained from 30 subjects. Height (H), mesiodistal diameter (MDD) and connecting space (CS) of the anterior teeth were measured with a digital calliper on the plaster models and with the orthodontic software on the digital models. Validity was assessed using a 2-tailed paired t-test; the reliability of measurements for intra-examiner was evaluated with the Intra-class Correl…
Thermodynamic correction of particle concentrations measured by underwing probes on fast-flying aircraft
2016
Particle concentration measurements with underwing probes on aircraft are impacted by air compression upstream of the instrument body as a function of flight velocity. In particular, for fast-flying aircraft the necessity arises to account for compression of the air sample volume. Hence, a correction procedure is needed to invert measured particle number concentrations to ambient conditions that is commonly applicable to different instruments to gain comparable results. In the compression region where the detection of particles occurs (i.e. under factual measurement conditions), pressure and temperature of the air sample are increased compared to ambient (undisturbed) conditions in certain …
Breakdown of the isobaric multiplet mass equation (IMME) at A=33, T=3/2
2000
Mass measurements on 3 3 , 3 4 , 4 2 , 4 3 Ar were performed using the Penning trap mass spectrometer ISOLTRAP and a newly constructed linear Paul trap. This arrangement allowed us, for the first time, to extend Penning trap mass measurements to nuclides with half-lives below one second ( 33 Ar : T 1 / 2 = 174 ms ). A mass accuracy of about 10 − 7 ( δ m ≈ 4 keV ) was achieved for all investigated nuclides. The isobaric multiplet mass equation was checked for the A = 33 , T = 3 / 2 quartet and found to be inconsistent with the generally accepted quadratic form. peerReviewed
Precision 71Ga – 71Ge mass-difference measurement
2016
The 71Ga(νe, e−) 71Ge reaction Q value has been measured with the JYFLTRAP mass spectrometer at the IGISOL facility of the University of Jyv¨askyl¨a to Q = 232.443(93) keV. This value agrees with previous measurements, though it features a much higher accuracy. The Q value is being discussed in the context of the solar neutrino capture rate in 71Ga. peerReviewed
Single-particle and collective excitations in the transitional nucleus 166Os
2021
The mean lifetimes of the lowest energy 2+, 8+ and 9− states in 166Os have been measured using the recoil distance Doppler-shift method in conjunction with a selective recoil-decay tagging technique. These measurements extend studies into the most neutron-deficient mass region accessible to current experimental methods. The B(E2; 2+ → 0+) = 7(2) W.u. extracted from these measurements is markedly lower than those observed in the heavier even-mass Os isotopes. The 8+ and 9− states yield reduced transition probabilities that are consistent with single-particle transitions. While these values may indicate a departure from collective structure, the level scheme and the underlying nuclear configu…
Morelloflavone, a novel biflavonoid inhibitor of human secretory phospholipase A2 with anti-inflammatory activity
1997
Abstract The flavanonylflavone morelloflavone inhibited secretory phospholipase A 2 (PLA 2 ) in vitro , with a high potency on the human recombinant synovial and bee venom enzymes ( IC 50 = 0.9 and 0.6 μM, respectively). The inhibition was apparently irreversible. In contrast, the compound was inactive on cytosolic PLA 2 activity from human monocytes. Morelloflavone scavenged reactive oxygen species generated by human neutrophils ( IC 50 = 2.7 and 1.8 μM for luminol and lucigenin, respectively) but did not modify cellular responses such as degranulation or eicosanoid release. This biflavonoid exerted anti-inflammatory effects in animal models, with a potent inhibition of 12-O-tetradecanoylp…