University of Twente Publications
University of Twente Repository provides publications of UT scientific staff, in many cases full text and publicly available.
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Mostrando recursos 1 - 20 de 22,542
Quantum-secure authentication of a physical unclonable key - Goorden, S.A.; Horstmann, M.; Mosk, A.P.; Skoric, B.; Pinkse, P.W.H.
Authentication of persons and objects is a crucial aspect
of security. We experimentally demonstrate quantumsecure
authentication (QSA) of a classical multiplescattering
key. The key is authenticated by illuminating
it with a light pulse containing fewer photons than
spatial degrees of freedom and verifying the spatial
shape of the reflected light. Quantum-physical principles
forbid an attacker to fully characterize the incident
light pulse. Therefore, he cannot emulate the key by
digitally constructing the expected optical response,
even if all information about the key is publicly known.
QSA uses a key that cannot be copied due to technological
limitations and is quantum-secure against digital
emulation. Moreover, QSA does not depend on secrecy
of stored data, does...
Mechanical ventilation-induced intrathoracic pressure distribution and heart-lung interactions - Lansdorp, B.; Hofhuizen, C.; Lavieren, M.A. van; Swieten, H. van; Lemson, J.; Putten, M.J.A.M. van; Hoeven, J.G. van der; Pickkers, P.
Mechanical ventilation causes cyclic changes in the heart's preload and afterload, thereby influencing the circulation. However, our understanding of the exact physiology of this cardiopulmonary interaction is limited. We aimed to thoroughly determine airway pressure distribution, how this is influenced by tidal volume and chest compliance, and its interaction with the circulation in humans during mechanical ventilation.
DESIGN: Intervention study.
SETTING: ICU of a university hospital.
PATIENTS: Twenty mechanically ventilated patients following coronary artery bypass grafting surgery.
INTERVENTION: Patients were monitored during controlled mechanical ventilation at tidal volumes of 4, 6, 8, and 10 mL/kg with normal and decreased chest compliance (by elastic...
Intensive care unit depth of sleep: Proof of concept of a simple electroencephalography index in the non-sedated - Reinke, L.; Hoeven, J.H. van der; Putten, M.J.A.M. van; Dieperink, W.; Tulleken, J.E.
Intensive care unit (ICU) patients are known to experience severely disturbed sleep, with possible detrimental effects on short- and long- term outcomes. Investigation into the exact causes and effects of disturbed sleep has been hampered by cumbersome and time consuming methods of measuring and staging sleep. We introduce a novel method for ICU depth of sleep analysis, the ICU depth of sleep index (IDOS index), using single channel electroencephalography (EEG) and apply it to outpatient recordings. A proof of concept is shown in non-sedated ICU patients.
Polysomnographic (PSG) recordings of five ICU patients and 15 healthy outpatients were analyzed...
A neural mass model based on single cell dynamics to model pathophysiology - Zandt, Bas-Jan; Visser, S.; Putten, M.J.A.M. van; Haken, B. ten
Abstract Neural mass models are successful in modeling brain rhythms as observed in macroscopic measurements such as the electroencephalogram (EEG). While the synaptic current is explicitly modeled in current models, the single
cell electrophysiology is not taken into account. To allow for investigations of the effects of channel pathologies, channel blockers and ion concentrations on macroscopic activity, we formulate neural mass equations explicitly incorporating
the single cell dynamics by using a bottom-up approach. The mean and variance of the firing rate and synaptic input distributions are modeled. The firing rate curve (F(I)-curve) is used as link between the single cell and macroscopic...
High levels of procoagulant factors mediate the association between free thyroxine and the risk of venous thrombosis: the MEGA study - Debeij, J.; Zaane, B.; Dekkers, O.M.; Doggen, C.J.M.; Smit, J.W.A.; Zanten, A.P. van; Brandjes, D.P.M.; Büller, H.R.; Gerdes, V.E.A.; Rosendaal, F.R.; Cannegieter, S.C.
Thyroid hormone affects the coagulation system, but its effect on clinical disease is not clear. We determined the associations of levels of free thyroxine (FT4), thyroid-stimulating hormone (TSH) and anti-thyroid peroxidase antibodies (antiTPO) with levels of coagulation factors and the risk of venous thrombosis.
In a large population based case–control study (Multiple Environmental and Genetic Assessment of risk factors for venous thrombosis study) on the etiology of venous thrombosis, we determined the levels of FT4, TSH, antiTPO, factor FII, FVII, FVIII, FIX, FX, von Willebrand factor (VWF), antithrombin, protein C, protein S and fibrinogen in 2177 cases and 2826 controls.
Social science teachers on citizenship education: a comparative study of three European countries - Jeliazkova, Margarita
This paper presents a comparison of high school teachers’ views on citizenship education in three European countries – the Netherlands, Bulgaria, and Croatia.
In all these countries, citizenship is an important part of school curriculum. The teachers need to find ways to deal with the everyday dilemmas of teaching a concept so highly loaded with diverse political meanings. What kind of citizens would they educate? How would they find a balance between neutrality and indoctrination? These and other questions were posed to over 60 teachers in the three countries in interviews using Q‐methodology, a combination of quantitative and qualitative techniques. In...
Putting impact into context: the Janus face of the public value of arts and humanities research - Benneworth, Paul
This article provides an overview to the Forum on the Public Value of Arts and Humanities Research which follows it. The author argues that the current gloom in the arts and humanities as a result of the increasing pressure for societal utility does not recognise the complete picture. A growing number of scholars are seeking to understand how the social life of arts and humanities knowledge operates and how it flows into and has impact on society. Seven articles provide a variety of insights into understanding and mapping this ‘social life of knowledge’, and provide a glimmer of hope for...
Publishing and perishing: The critical importance of educational design research - Reeves, Thomas C.; McKenney, Susan; Herrington, Jan
The outcomes of educational systems continue to lag far behind expectations at all levels, primary, secondary, and tertiary. Meanwhile, the sheer amount of educational research published in refereed journals has expanded enormously. There is an obvious disconnect between the educational research papers published in professional journals or presented at academic conferences and any form of beneficial impact on the students, teachers, and other stakeholders in educational systems. This problem can be traced back to those professors and research supervisors engaged in the preparation of educational researchers who fail to convey to novice researchers important distinctions between the goals and methods...
Primary Chemical Sequence Ultimately Determines Crystal Thickness in Segmented All-Aliphatic Copolymers - Odarchenko, Y.I; Anokhin, D.V.; Doblas, D.; Rosenthal, M.; Hernandez, J.J.; Vidal, L.; Sijbrandi, N.J.; Kimenai, A.J.; Mes, E.P.C.; Broos, R.; Bar, G.; Dijkstra, P.J.; Feijen, J.; Soloviev, M.; Ivanov, D.A.
Thermoplastic elastomers (TPEs) are known to
exhibit a phase-separated morphology which depends on their
chemical structure and processing. The design of novel TPEs
with predefined properties which are also independent of the
material thermal history has so far remained a challenge. The
focus of this work is on the semicrystalline morphology of allaliphatic
thermoplastic elastomers consisting of alternating
polytetrahydrofuran (PTHF) segments and uniform glycine or
β-alanine bisoxalamide units. The thickness of the hard
segment crystals was found to be highly monodisperse and
independent of the sample thermal history. Using Nanocalorimetry, we observed that at cooling rates as high as 12 000 °C s−1
the bisoxalamide segments can still crystallize although the...
Robustness inembedded software for autonomous robots - Broenink, Jan; Brodskiy, Yury; Dresscher, Douwe; Stramigioli, Stefano
The European BRICS project aims to bring about a long-lasting change in robotics research and development in industry as well as in academia. It wants to change the current situation of non-interoperable, monolithic and single-sourcing robotic components into a situation that other domains have already reached: cost-effective access to interoperable infrastructure components, which can create a thriving ecosystem of innovative products and services. This article focuses on techniques that could be used to increase the level of robust autonomy of robots.
Shift rostering using decomposition: assign weekend shifts first - Veen, Egbert van der; Hans, Erwin W.; Post, Gerhard F.; Veltman, Bart
This paper introduces a shift rostering problem that surprisingly has not been studied in the literature: the weekend shift rostering problem. It is motivated by our experience that employees’ shift preferences predominantly focus on the weekends, since many social activities happen during weekends. The weekend rostering problem (WRP) addresses the rostering of weekend shifts, for which we design a problem-specific heuristic. We consider the WRP as the first phase of the shift rostering problem. To complete the shift roster, the second phase assigns the weekday shifts. This decomposition reflects how shift rosters are often created manually in practice, which makes...
The influence of subjective aging on health and longevity: A meta-analysis of longitudinal data - Westerhof, Gerben J.; Miche, Martina; Brothers, Allyson F.; Barrett, Anne E.; Diehl, Manfred; Montepare, Joann M.; Wahl, Hans-Werner; Wurm, Susanne
Evidence is accumulating on the effects of subjective aging—that is, how individuals perceive their own aging process—on health and survival in later life. The goal of this article is to synthesize findings of existing longitudinal studies through a meta-analysis. A systematic search in PsycInfo, Web of Science, Scopus, and Pubmed resulted in 19 longitudinal studies reporting effects of subjective aging on health, health behaviors, and longevity. The authors combine the outcomes reported in these studies using a random effects meta-analysis, assuming that there would be differences in effect sizes across studies. The meta-analysis resulted in an overall significant effect of...
The Leadership Role of the Ethicist: Balancing between the Authoritative and the Passive - Wynsberghe, Aimee van
The pervasive presence of Information and Communication technologies has profound effects on cultural norms and values. This relationship is most commonly referred to in terms of values embedded in a technology (Nissenbaum, 2001). To mitigate potential threats to values, researchers from a variety of disciplines advocate in favor of incorporating ethics into research and design processes. As Boenink (2013) rightly points out, however, there is little work done that outlines exactly what it is that the ethicist does when engaged in ‘ethics in the lab'. This paper aims to fill the gap that Boenink has identified and to contribute to...
Methods of evaluation and reflection in design research - McKenney, Susan; Reeves, Thomas C.
This contribution is concerned with the role of evaluation in design research with respect to the twin goals of informing the external scientific community about any new knowledge attained as well as driving the development of an effective intervention. This kind of evaluation is conscious, systematic, and formalized. Here, the term, evaluation, is used in a broad sense to refer to any kind of empirical testing of interventions that have been mapped out (designs) or constructed (prototypes). Reflection pertains to retrospective consideration of findings and observations rather than to assessment of personal performance. In this contribution, evaluation is described as...
Towards valid score reports in the Computer Program LOVS: A redesign study - Kleij, Fabienne M. van der; Eggen, Theo J.H.M.; Engelen, R.J.H.
Portraying the design research cycle: Professional development in Indian slums - Raval, Harini; McKenney, Susan; Pieters, Jules
Although para-teachers make up a substantial portion of the world’s educational work force, little empirical research has been conducted on their professional development. During the iterative process of analysis, design, evaluation, and revision, design research was conducted to gain insight into desirable characteristics of a professional development program for Indian para-teachers in urban slums. The design study flanking evolution of the para-teacher professional development program helped (re)shape each cycle of implementation, and to track lasting effects on organizational climate, teacher agency and pupil learning. Because long-term, high-quality design studies in the field of education are rare, this paper focuses on...
Pain management in trauma patients in (pre)hospital based emergency care: current practice versus new guideline - Scholten, A.C.; Berben, S.A.A.; Westmaas, A.H.; Grunsven, P.M.; Vaal, E.T. de; Rood, Pleunie P.M.; Hoogerwerf, N.; Doggen, C.J.M.; Schoonhoven, L.
Acute pain in trauma patients in emergency care is still undertreated. Early pain treatment is assumed to effectively reduce pain in patients and improve long-term outcomes. In order to improve pain management in the chain of emergency care, a national evidence-based guideline was developed. The aim of this study was to assess whether current practice is in compliance with the guideline ‘Pain management for trauma patients in the chain of emergency care’ from the Netherlands Association for Emergency Nurses (in Dutch NVSHV), and to evaluate early and initial pain management for adult trauma patients in emergency care.
Chart reviews were conducted...