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2. Macroscopic analysis and modelling of multi-class, flexible-lane traffic

Author

Knoop, Victor L., Schakel, Wouter J., van Oijen, Tim P., and Leclercq, Ludovic

Subjects
Physics - Physics and Society
Abstract

An excessive demand of vehicles to a motorway bottleneck leads to traffic jams. Motorbikes are narrow and can drive next to each other in a lane, or in-between lanes in low speeds. This paper analyses the resulting traffic characteristics and presents numerical scheme for a macroscopic traffic flow model for these two classes. The behavior included is as follows. If there are two motorbikes behind each other, they can travel next to each other in one lane, occupying the space of one car. Also, at low speeds of car traffic, they can go in between the main lanes, creating a so-called filtering lane. The paper numerically derives functions of class-specific speeds as function of the density of both classes, incorporating flexible lane usage dependent on the speed. The roadway capacity as function of the motorbike fraction is derived, which interesting can be in different types of phases (with motorbikes at higher speeds or not). We also present a numerical scheme to analyse the dynamics of this multi-class system. We apply the model to an example case, revealing the properties of the traffic stream , queue dynamics and class specific travel times. The model can help in showing the relative advantage in travel time of switching to a motorbike.

Published
2023

4. The multiple mediating effects of vision-specific factors and depression on the association between visual impairment severity and fatigue: a path analysis study

Author

Wouter Schakel, Christina Bode, Peter M. van de Ven, Hilde P. A. van der Aa, Carel T. J. Hulshof, Gerardus H. M. B. van Rens, and Ruth M. A. van Nispen

Subjects
Visual impairment, Fatigue, Depression, Vision-specific quality of life, Low vision, Structural equation modeling, Psychiatry, RC435-571
Abstract

Abstract Background Severe fatigue is a common symptom for people with visual impairment, with a detrimental effect on emotional functioning, cognition, work capacity and activities of daily living. A previous study found that depression was one of the most important determinants of fatigue, but less is known about disease-specific factors in this patient population. This study aimed to explore the association between visual impairment severity and fatigue in adults with low vision, both directly and indirectly, with vision-specific factors and depression as potential mediators. Methods Cross-sectional data were collected from 220 Dutch low vision service patients by telephone interviews. Fatigue was defined as a latent variable by severity and impact on daily life. Potential mediators included vision-related symptoms, adaptation to vision loss and depression. Hypothesized structural equation models were constructed in Mplus to test (in)direct effects of visual impairment severity (mild/moderate, severe, blindness) on fatigue through above mentioned variables. Results The final model explained 60% of fatigue variance and revealed a significant total effect of visual impairment severity on fatigue. Patients with severe visual impairment (reference group) had significantly higher fatigue symptoms compared to those with mild/moderate visual impairment (β = -0.50, 95% bias-corrected confidence interval [BC CI] [-0.86, -0.16]) and those with blindness (β = -0.44, 95% BC CI [-0.80, -0.07]). Eye strain & light disturbance, depression and vision-related mobility mediated the fatigue difference between the severe and mild/moderate visual impairment categories. The fatigue difference between the severe visual impairment and blindness categories was solely explained by eye strain & light disturbance. Moreover, depressive symptoms (β = 0.65, p

Published
2024
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5. Towards retrospective motion correction and reconstruction for clinical 3D brain MRI protocols with a reference contrast

Author

Rizzuti, Gabrio, Schakel, Tim, Huttinga, Niek R. F., Dankbaar, Jan Willem, van Leeuwen, Tristan, and Sbrizzi, Alessandro

Subjects
Electrical Engineering and Systems Science - Image and Video Processing
Abstract

Motion artifacts often spoil the radiological interpretation of MR images, and in the most severe cases the scan needs be repeated, with additional costs for the provider. We discuss the application of a novel 3D retrospective rigid motion correction and reconstruction scheme for MRI, which leverages multiple scans contained in a MR session. Typically, in a multi-contrast MR session, motion does not equally affect all the scans, and some motion-free scans are generally available, so that we can exploit their anatomic similarity. The uncorrupted scan is used as a reference in a generalized rigid-motion registration problem to remove the motion artifacts affecting the corrupted scans. We discuss the potential of the proposed algorithm with a prospective in-vivo study and clinical 3D brain protocols. This framework can be easily incorporated into the existing clinical practice with no disruption to the conventional workflow.

Published
2023

6. Internationalisation and Study Success: Class Attendance and the Delicate Balance between Collaborative Learning and Being Lost in Translation

Author

Bijsmans, Patrick, Schakel, Arjan H., Baykal, Asena, and Hegewald, Sven

Abstract

The internationalisation of Higher Education is broadly seen as a positive development. It is a process that is said to contribute to intercultural skills acquisition, which is deemed crucial in today's globalised society. Yet, research has shown that the benefits of being confronted with other ideas and viewpoints can get lost in translation due to different languages and academic cultures. We set out to explore the impact of the international classroom on study success and argue that there might be an optimum level of internationalisation. Based on a dataset that includes more than 2822 GPA scores for 836 students from four first-year cohorts of an international Bachelor in European Studies, we find strong empirical evidence that students' study success is lower when there are few (below 3) or many (above 6) different nationalities in the classroom. We find the strongest effects of internationalisation for students who regularly attend class (i.e. 80-90%). Hence, we present strong evidence that internationalisation has a both a negative and a positive impact on students' study success but students will only experience these beneficial and detrimental effects of learning in an international environment when they attend class.

Published
2022
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9. Feasibility of cardiac-synchronized quantitative T1 and T2 mapping on a hybrid 1.5 Tesla magnetic resonance imaging and linear accelerator system

Author

Osman Akdag, Stefano Mandija, Astrid L.H.M.W. van Lier, Pim T.S. Borman, Tim Schakel, Eveline Alberts, Oscar van der Heide, Rutger J. Hassink, Joost J.C. Verhoeff, Firdaus A.A. Mohamed Hoesein, Bas W. Raaymakers, and Martin F. Fast

Subjects
MR-linac, MRI, Quantitative cardiac MRI, MRI-guided radiotherapy, Cardiac MR-linac, Medical physics. Medical radiology. Nuclear medicine, R895-920, Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

Background and Purpose: The heart is important in radiotherapy either as target or organ at risk. Quantitative T1 and T2 cardiac magnetic resonance imaging (qMRI) may aid in target definition for cardiac radioablation, and imaging biomarker for cardiotoxicity assessment. Hybrid MR-linac devices could facilitate daily cardiac qMRI of the heart in radiotherapy. The aim of this work was therefore to enable cardiac-synchronized T1 and T2 mapping on a 1.5 T MR-linac and test the reproducibility of these sequences on phantoms and in vivo between the MR-linac and a diagnostic 1.5 T MRI scanner. Materials and methods: Cardiac-synchronized MRI was performed on the MR-linac using a wireless peripheral pulse-oximeter unit. Diagnostically used T1 and T2 mapping sequences were acquired twice on the MR-linac and on a 1.5 T MR-simulator for a gel phantom and 5 healthy volunteers in breath-hold. Phantom T1 and T2 values were compared to gold-standard measurements and percentage errors (PE) were computed, where negative/positive PE indicate underestimations/overestimations. Manually selected regions-of-interest were used for in vivo intra/inter scanner evaluation. Results: Cardiac-synchronized T1 and T2 qMRI was enabled after successful hardware installation on the MR-linac. From the phantom experiments, the measured T1/T2 relaxation times had a maximum percentage error (PE) of −4.4%/−8.8% on the MR-simulator and a maximum PE of −3.2%/+8.6% on the MR-linac. Mean T1/T2 of the myocardium were 1012±34/51±2 ms on the MR-simulator and 1034±42/51±1 ms on the MR-linac. Conclusions: Accurate cardiac-synchronized T1 and T2 mapping is feasible on a 1.5 T MR-linac and might enable novel plan adaptation workflows and cardiotoxicity assessments.

Published
2022
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11. Differential Placental DNA Methylation of NR3C1 in Extremely Preterm Infants With Poorer Neurological Functioning

Author

Nienke H. van Dokkum, Sofia Bachini, Rikst Nynke Verkaik-Schakel, Dyvonne H. Baptist, Sahar Salavati, Karianne E. Kraft, Sicco A. Scherjon, Arend F. Bos, and Torsten Plösch

Subjects
placenta, DNA methylation, stress, prematurity, neurological functioning, Pediatrics, RJ1-570
Abstract

BackgroundUnderstanding underlying mechanisms of neurodevelopmental impairment following preterm birth may enhance opportunities for targeted interventions. We aimed to assess whether placental DNA methylation of selected genes affected early neurological functioning in preterm infants.MethodsWe included 43 infants, with gestational age

Published
2022
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12. Technical design report for the endcap disc DIRC

Author

F Davì, W Erni, B Krusche, M Steinacher, N Walford, H Liu, Z Liu, B Liu, X Shen, C Wang, J Zhao, M Albrecht, T Erlen, F Feldbauer, M Fink, V Freudenreich, M Fritsch, F H Heinsius, T Held, T Holtmann, I Keshk, H Koch, B Kopf, M Kuhlmann, M Kümmel, S Leiber, P Musiol, A Mustafa, M Pelizäus, A Pitka, G Reicherz, M Richter, C Schnier, T Schröder, S Sersin, L Sohl, C Sowa, M Steinke, T Triffterer, U Wiedner, R Beck, C Hammann, J Hartmann, B Ketzer, M Kube, M Rossbach, C Schmidt, R Schmitz, U Thoma, M Urban, A Bianconi, M Bragadireanu, D Pantea, W Czyzycki, M Domagala, G Filo, J Jaworowski, M Krawczyk, E Lisowski, F Lisowski, M Michałk, J Płażek, K Korcyl, A Kozela, P Kulessa, P Lebiedowicz, K Pysz, W Schäfer, A Szczurek, T Fiutowski, M Idzik, B Mindur, K Swientek, J Biernat, B Kamys, S Kistryn, G Korcyl, W Krzemien, A Magiera, P Moskal, W Przygoda, Z Rudy, P Salabura, J Smyrski, P Strzempek, A Wronska, I Augustin, R Böhm, I Lehmann, D Nicmorus Marinescu, L Schmitt, V Varentsov, M Al-Turany, A Belias, H Deppe, N Divani Veis, R Dzhygadlo, H Flemming, A Gerhardt, K Götzen, R Karabowicz, U Kurilla, D Lehmann, S Löchner, J Lühning, U Lynen, S Nakhoul, H Orth, K Peters, T Saito, G Schepers, C J Schmidt, C Schwarz, J Schwiening, A Täschner, M Traxler, B Voss, P Wieczorek, A Wilms, V Abazov, G Alexeev, V A Arefiev, V Astakhov, M Yu Barabanov, B V Batyunya, V Kh Dodokhov, A Efremov, A Fechtchenko, A Galoyan, G Golovanov, E K Koshurnikov, Y Yu Lobanov, V I Lobanov, V Malyshev, A G Olshevskiy, A A Piskun, A Samartsev, M G Sapozhnikov, N B Skachkov, A N Skachkova, E A Strokovsky, V Tokmenin, V Uzhinsky, A Verkheev, A Vodopianov, N I Zhuravlev, A Zinchenko, D Branford, D Glazier, D Watts, M Böhm, W Eyrich, A Lehmann, D Miehling, M Pfaffinger, S Stelter, F Uhlig, S Dobbs, K Seth, A Tomaradze, T Xiao, D Bettoni, A Ali, A Hamdi, M Krebs, F Nerling, V Akishina, S Gorbunov, I Kisel, G Kozlov, M Pugach, M Zyzak, N Bianchi, P Gianotti, C Guaraldo, V Lucherini, G Bracco, S Bodenschatz, K T Brinkmann, V Di Pietro, S Diehl, V Dormenev, M Düren, E Etzelmüller, K Föhl, M Galuska, T Geßler, E Gutz, C Hahn, A Hayrapetyan, M Kesselkaul, W Kühn, T Kuske, J S Lange, Y Liang, O Merle, V Metag, M Moritz, M Nanova, R Novotny, T Quagli, A Riccardi, J Rieke, M Schmidt, R Schnell, H Stenzel, M Strickert, U Thöring, T Wasem, B Wohlfahrt, H G Zaunick, E Tomasi-Gustafsson, D Ireland, G Rosner, B Seitz, P N Deepak, A Kulkarni, A Apostolou, M Babai, M Kavatsyuk, H Loehner, J Messchendorp, P Schakel, M Tiemens, J C van der Weele, S Vejdani, K Dutta, K Kalita, H Sohlbach, M Bai, L Bianchi, M Büscher, A Derichs, R Dosdall, A Erven, V Fracassi, A Gillitzer, F Goldenbaum, D Grunwald, L Jokhovets, G Kemmerling, H Kleines, A Lai, A Lehrach, M Mikirtychyants, S Orfanitski, D Prasuhn, E Prencipe, J Pütz, J Ritman, E Rosenthal, S Schadmand, T Sefzick, V Serdyuk, G Sterzenbach, T Stockmanns, P Wintz, P Wüstner, H Xu, Y Zhou, Z Li, X Ma, V Rigato, L Isaksson, P Achenbach, A Aycock, O Corell, A Denig, M Distler, M Hoek, W Lauth, H Merkel, U Müller, J Pochodzalla, S Sanchez, S Schlimme, C Sfienti, M Thiel, M Zambrana, H Ahmadi, S Ahmed, S Bleser, L Capozza, M Cardinali, A Dbeyssi, A Ehret, B Fröhlich, P Grasemann, S Haasler, D Izard, J Jorge, D Khaneft, R Klasen, R Kliemt, J Köhler, H H Leithoff, D Lin, F Maas, S Maldaner, M Michel, M C Mora Espí, C Morales Morales, C Motzko, O Noll, S Pflüger, D Rodríguez Piñeiro, M Steinen, E Walaa, S Wolff, I Zimmermann, A Fedorov, M Korzhik, O Missevitch, P Balanutsa, V Chernetsky, A Demekhin, A Dolgolenko, P Fedorets, A Gerasimov, V Goryachev, D Y Kirin, V A Matveev, A V Stavinskiy, A Balashoff, A Boukharov, O Malyshev, I Marishev, V Chandratre, V Datar, V Jha, H Kumawat, A K Mohanty, A Parmar, A K Rai, B Roy, G Sonika, C Fritzsch, S Grieser, A K Hergemöller, B Hetz, N Hüsken, A Khoukaz, J P Wessels, C Herold, K Khosonthongkee, C Kobdaj, A Limphirat, P Srisawad, Y Yan, A E Blinov, S Kononov, E A Kravchenko, E Antokhin, M Barnyakov, A Yu Barnyakov, K Beloborodov, V E Blinov, V S Bobrovnikov, I A Kuyanov, A P Onuchin, S Pivovarov, E Pyata, S Serednyakov, Y Tikhonov, R Kunne, D Marchand, B Ramstein, J van de Wiele, Y Wang, G Boca, V Burian, M Finger, A Nikolovova, M Pesek, M Peskova, M Pfeffer, I Prochazka, M Slunecka, P Gallus, V Jary, J Novy, M Tomasek, M Virius, V Vrba, V Abramov, N Belikov, S Bukreeva, A Davidenko, A Derevschikov, Y Goncharenko, V Grishin, V Kachanov, V Kormilitsin, A Levin, Y Melnik, N Minaev, V Mochalov, D Morozov, L Nogach, S Poslavskiy, A Ryazantsev, S Ryzhikov, P Semenov, I Shein, A Uzunian, A Vasiliev, A Yakutin, U Roy, B Yabsley, S Belostotski, G Gavrilov, A Izotov, S Manaenkov, O Miklukho, D Veretennikov, A Zhdanov, T Bäck, B Cederwall, K Makonyi, M Preston, P E Tegner, D Wölbing, S Godre, M P Bussa, S Marcello, S Spataro, F Iazzi, R Introzzi, A Lavagno, D Calvo, P De Remigis, A Filippi, G Mazza, A Rivetti, R Wheadon, A Martin, H Calen, W Ikegami Andersson, T Johansson, A Kupsc, P Marciniewski, M Papenbrock, J Pettersson, J Regina, K Schönning, M Wolke, J Diaz, V Pothodi Chackara, A Chlopik, G Kesik, D Melnychuk, B Slowinski, A Trzcinski, M Wojciechowski, S Wronka, B Zwieglinski, P Bühler, J Marton, D Steinschaden, K Suzuki, E Widmann, S Zimmermann, and J Zmeskal

Subjects
Subatomär fysik, Nuclear and High Energy Physics, PANDA, Subatomic Physics, Acceleratorfysik och instrumentering, technical design report, particle identification, Accelerator Physics and Instrumentation, Cherenkov detector
Abstract

PANDA (anti-proton annihiliation at Darmstadt) is planned to be one of the four main experiments at the future international accelerator complex FAIR (Facility for Antiproton and Ion Research) in Darmstadt, Germany. It is going to address fundamental questions of hadron physics and quantum chromodynamics using cooled antiproton beams with a high intensity and and momenta between 1.5 and 15 GeV/c. PANDA is designed to reach a maximum luminosity of 2 × 1032 cm−2 s. Most of the physics programs require an excellent particle identification (PID). The PID of hadronic states at the forward endcap of the target spectrometer will be done by a fast and compact Cherenkov detector that uses the detection of internally reflected Cherenkov light (DIRC) principle. It is designed to cover the polar angle range from 5° to 22° and to provide a separation power for the separation of charged pions and kaons up to 3 standard deviations (s.d.) for particle momenta up to 4 GeV/c in order to cover the important particle phase space. This document describes the technical design and the expected performance of the novel PANDA disc DIRC detector that has not been used in any other high energy physics experiment before. The performance has been studied with Monte-Carlo simulations and various beam tests at DESY and CERN. The final design meets all PANDA requirements and guarantees sufficient safety margins.

Published
2022

14. Technology review of the Northern Bowen and Galilee basins

Author

Scott, Michael P., Johnson Jr, Raymond, Spilsbury-Schakel, Janny, and Garnett, Andrew

Abstract

This paper reviews and summarises the work that has been conducted and the technology used in exploring and developing the Northern Bowen and Galilee basins in Queensland. It examines the methods operators have used in drilling, completing and testing wells through the varying stages of exploration, appraisal and development in the different parts of the basins. It examines all the work conducted in the Betts Creek Beds and Aramac Coal Measures throughout the Galilee Basin; the Moranbah Coal Measures, Rangal Coal Measures and Fort Cooper Coal Measures in the Moranbah area of the Bowen Basin; the Rangal Coal Measures, Burngrove Formation and Fairhill Formation in the Blackwater area; the conventional and coal seam gas developments in the Rolleston area, including the Bandanna Formation plays near Injune; and the Baralaba Coal Measures in the Moura area. Wells have been completed both open and cased hole with techniques including vertical wells, both with and without hydraulic fracturing and cavitation, as well as a variety of horizontal well designs including surface to inseam wells with vertical intercept wells and multiple lateral sections, chevron wells and both heel and toe intercepts. Operators have also implemented multiple wells on one pad. Throughout the Northern Bowen Basin, horizontal well drilling has been a key technology in commercial development. Generally, activities within the Galilee Basin have not progressed as far as the Bowen Basin, but nevertheless, horizontal wells are also emerging as a key technology.

Published
2023
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15. Car-Following Properties of a Commercial Adaptive Cruise Control System: A Pilot Field Test

Author

Raju, Narayana, Schakel, Wouter, Reddy, Nagarjun, Dong, Yongqi, and Farah, Haneen

Abstract

Automated driving systems, which can take over certain dynamic driving tasks from the driver, are becoming increasingly available in commercial vehicles. One of these automated driving systems widely introduced in commercial vehicles is adaptive cruise control (ACC). This system is designed to maintain certain desired driving speeds and time headways as chosen by drivers and based on the settings available within the system. The properties and actual performance of these systems will affect the traffic flow and its stability. However, the specific properties and their workings are rarely publicly available. Therefore, the main aim of this paper is to test the actual performance of a commercial ACC system under different desired speed and distance gap settings, as well as driving modes in a car-following situation. For this purpose, a pilot field test was conducted in the Netherlands in which two identical commercial vehicles equipped with ACC systems were driven simultaneously. The first vehicle was used to create a pre-specified speed profile by adapting the ACC system settings manually, whereas the second vehicle followed the lead vehicle when the ACC system was engaged to test its actual performance. The main findings indicate that the different system settings affect the car-following indicators, and system response times were found to be comparable to human response times. The eco mode was found to affect some of the car-following indicators, and it does not deteriorate safety below the safety level of driving with short headway setting in drive mode.

Published
2022
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16. Altered neurodevelopmental DNA methylation status after fetal growth restriction with brain-sparing

Author

Richter, Anne E., Bekkering-Bauer, Iris, Verkaik-Schakel, Rikst Nynke, Leeuwerke, Mariëtte, Tanis, Jozien C., Bilardo, Caterina M., Kooi, Elisabeth M. W., Scherjon, Sicco A., Bos, Arend F., and Plösch, Torsten

Abstract

AbstractIt is under debate how preferential perfusion of the brain (brain-sparing) in fetal growth restriction (FGR) relates to long-term neurodevelopmental outcome. Epigenetic modification of neurotrophic genes by altered fetal oxygenation may be involved. To explore this theory, we performed a follow-up study of 21 FGR children, in whom we prospectively measured the prenatal cerebroplacental ratio (CPR) with Doppler sonography. At 4 years of age, we tested their neurodevelopmental outcome using the Wechsler Preschool and Primary Scale of Intelligence, the Child Behavior Checklist, and the Behavior Rating Inventory of Executive Function. In addition, we collected their buccal DNA to determine the methylation status at predefined genetic regions within the genes hypoxia-inducible factor-1 alpha (HIF1A), vascular endothelial growth factor A (VEGFA), erythropoietin (EPO), EPO-receptor (EPOR), brain-derived neurotrophic factor (BDNF), and neurotrophic tyrosine kinase, receptor, type 2 (NTRK2) by pyrosequencing. We found that FGR children with fetal brain-sparing (CPR <1, n= 8) demonstrated a trend (0.05 < p< 0.1) toward hypermethylation of HIF1Aand VEGFAat their hypoxia-response element (HRE) compared with FGR children without fetal brain-sparing. Moreover, in cases with fetal brain-sparing, we observed statistically significant hypermethylation at a binding site for cyclic adenosine monophophate response element binding protein (CREB) of BDNFpromoter exon 4 and hypomethylation at an HRE located within the NTRK2promoter (both p<0.05). Hypermethylation of VEGFAwas associated with a poorer Performance Intelligence Quotient, while hypermethylation of BDNFwas associated with better inhibitory self-control (both p<0.05). These results led us to formulate the hypothesis that early oxygen-dependent epigenetic alterations due to hemodynamic alterations in FGR may be associated with altered neurodevelopmental outcome in later life. We recommend further studies to test this hypothesis.

Published
2022
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