References of "Scientific journals"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailVoluntary disclosure, tax avoidance and family firms
Derouiche, Imen UL; Boubaker, sabri; Nguyen, Hung

in Journal of Management and Governance (2021)

This study examines the effect of voluntary disclosure in annual reports on tax avoidance activities. The agency theory of tax avoidance suggests that tax sheltering is associated with important agency ... [more ▼]

This study examines the effect of voluntary disclosure in annual reports on tax avoidance activities. The agency theory of tax avoidance suggests that tax sheltering is associated with important agency costs, underlining the importance of corporate governance mechanisms such as voluntary disclosure in shaping tax planning. Using a sample of 3448 firm-year observations of French listed firms over 2007–2013, the results show that voluntary disclosure is associated with lower tax avoidance activities, providing evidence that this disclosure can be seen as an effective monitoring tool that reduces the insiders’ likelihood to engage in rent extraction through tax avoidance activities. The results also indicate that the negative effect of voluntary disclosure on tax avoidance is significant only when family control is below 40%, suggesting that the disciplinary role of voluntary disclosure is limited to firms with relatively low family control levels. Overall, our findings are consistent with the agency theory of tax avoidance and highlight the important role of corporate disclosure in improving corporate governance. [less ▲]

Detailed reference viewed: 46 (0 UL)
Full Text
Peer Reviewed
See detailRules, Norms and Practices. A Comparative Study Exploring Disposal Practices and Facilities in Northern Europe
Kmec, Sonja UL; Nordh, Helena; House, Danielle et al

in Omega: Journal of Death and Dying (2021), 83(4),

We identify and analyse practices and management regimes around burial and handling of ashes across eight case study towns within six Northern European countries. We analyse management of cemeteries and ... [more ▼]

We identify and analyse practices and management regimes around burial and handling of ashes across eight case study towns within six Northern European countries. We analyse management of cemeteries and crematoria gardens, majority practices and provision for minority communities, including various burial types, cremated remains, the re-use of graves, and costs for interments. Comparative data is drawn from analysis of national and local regulations, interviews with stakeholders, and observations at cemeteries and crematoria gardens. The findings show significant variation in national and local regulations and practices for burial and cremation particularly around the re-use of graves, handling of ashes and costs for grave space and cremation. We identify the opportunities and constraints of these variations in terms of accessibility, diversity and equality; and argue for national directions to avoid unequal treatment within nations. Furthermore, we stress the importance of a liberal and inclusive management of European cemeteries and crematoria gardens. [less ▲]

Detailed reference viewed: 88 (3 UL)
Full Text
Peer Reviewed
See detailAnalysis of MaaS membership attributes: an agent-based approach
Cisterna, Carolina UL; Bigi, Federico UL; Tinessa, Fiore et al

in Transportation Research Procedia (2021)

Detailed reference viewed: 35 (0 UL)
Full Text
Peer Reviewed
See detailAdaptive Practice Quizzing in a University Lecture: A Pre-Registered Field Experiment
Heitmann, Svenja; Obergassel, Niklas; Fries, Stefan et al

in Journal of Applied Research in Memory and Cognition (2021)

Providing quiz questions has emerged as a powerful means to support learning. However, it is still unclear whether adaptive practice quizzing will enhance beneficial effects in authentic contexts. To ... [more ▼]

Providing quiz questions has emerged as a powerful means to support learning. However, it is still unclear whether adaptive practice quizzing will enhance beneficial effects in authentic contexts. To address this question, university students (N = 188; n = 155 female) were randomly assigned to employ either adaptive practice quizzing, nonadaptive practice quizzing, or note-taking following three consecutive sessions of a standard psychology university lecture for undergraduate pre-service teachers. In the adaptive practice quizzing condition, quiz questions were adapted to learners’ expertise via cognitive demand ratings, whereas in the non-adaptive condition quiz questions followed a fixed sequence. Students in the adaptive practice quizzing condition outperformed those in the nonadaptive condition after a two-week delay, but not after a one-week delay. Exploratory mediation analyses show that performance on the quiz questions during the learning phase seems to be partly responsible for this effect. [less ▲]

Detailed reference viewed: 46 (1 UL)
Full Text
Peer Reviewed
See detailThe evolution and social determinants of mental health during the first wave of the COVID-19 outbreak in Luxembourg
Ribeiro, Fabiana UL; Schröder, Valerie UL; Krüger, Rejko UL et al

in Psychiatry Research (2021), 303

Studies have been showing a negative impact of pandemic control measures on mental health. However, few studies assessed these effects longitudinally during the peak of the first wave of the COVID-19 ... [more ▼]

Studies have been showing a negative impact of pandemic control measures on mental health. However, few studies assessed these effects longitudinally during the peak of the first wave of the COVID-19 pandemic. The goals of this study were to explore whether differential effects of COVID-19 restrictions on mental health could be observed by sex and age in a Luxembourgish nationally representative sample during the initial outbreak of COVID-19. Furthermore, we aimed to assess whether there are differences in risk and protective factors longitudinally at two assessment times. A total of 1,756 respondents aged 18 years and older (50.74% women) reported sociodemographic and socio-economic characteristics, depression, anxiety, stress, and loneliness. Women and younger respondents reported higher rates of severe depression and anxiety symptoms, suggesting higher vulnerability to the pandemic control measures. This study contributes to the investigation of mental health consequences of the pandemic and the pandemic control measures, particularly related to shifts in care task responsibilities, gender and socio-economic inequalities, as well as younger groups' uncertainty about the future. [less ▲]

Detailed reference viewed: 81 (4 UL)
Full Text
Peer Reviewed
See detailChronique de droit européen de la consommation 2020 - 2021
Poillot, Elise UL

in Journal de Droit Européen (2021)

Detailed reference viewed: 30 (3 UL)
Full Text
Peer Reviewed
See detailBorderland Child Heterotopias. A Case Study on the Belgian-German Borderlands
Venken, Machteld UL

in Journal of Borderlands Studies (2021), 36(2), 159-180

This article investigates the capacities of children to participate actively in their lives in the Belgian-German borderlands in the time period between World War I and World War II. The article ... [more ▼]

This article investigates the capacities of children to participate actively in their lives in the Belgian-German borderlands in the time period between World War I and World War II. The article interprets a body of historical sources that has hitherto been left unexplored – namely, borderland child ego documents – with the help of insights from child studies and border studies. These ego documents unfold as borderland child heterotopias. Borderland child heterotopias include material places and creative linguistic loci established by or for those considered in crisis in relation to the rest of society based on their age within or outside child spaces of modernity. The borderland child heterotopias offer a unique gateway to borderland children’s past imaginations for a better world. [less ▲]

Detailed reference viewed: 96 (12 UL)
Full Text
Peer Reviewed
See detailEntered into Force: The 2020 Space Law of Luxembourg
Hofmann, Mahulena UL

in Air and Space Law (2021), 46(4-5), 587-602

In comparison with the broad spectrum of Luxembourg’s activities, the national legal framework allowing for authorizing and supervising activities under Luxembourg’s jurisdiction was narrow. The 1991 Law ... [more ▼]

In comparison with the broad spectrum of Luxembourg’s activities, the national legal framework allowing for authorizing and supervising activities under Luxembourg’s jurisdiction was narrow. The 1991 Law on Electronic Media allowed for the authorization of the SES telecommunication satellites. The 2017 Space Resources Law was adopted speedily to welcome operators in this specific area. A legal basis for other activities was missing – there were no binding provisions enabling domestic authorities to regulate launching of space objects, Earth observation, navigation, or on-orbit activities. The Law of 15 December 2020 on Space Activity fills this gap. From 1 January 2021 onwards, future Luxembourg space operators can apply for an authorization of their space activity in or out of its territory, and the conditions for a successful application are known, as are the price and consequences. [less ▲]

Detailed reference viewed: 192 (10 UL)
Full Text
Peer Reviewed
See detailWhen, why, and how do People Deviate from Physical Distancing Measures During the COVID-19 Pandemic: A Mixed-Methods Study
Van Alboom, Maité; Baert, Fleur; Wauters, Aline et al

in Psychologica Belgica (2021)

To limit the spread of COVID-19, many countries, including Belgium, have installed physical distancing measures. Yet, adherence to these newly installed behavioral measures has been described as ... [more ▼]

To limit the spread of COVID-19, many countries, including Belgium, have installed physical distancing measures. Yet, adherence to these newly installed behavioral measures has been described as challenging and effortful. Based on the Health Action Process Approach (HAPA) model, this study performed an in-depth evaluation of when, why, and how people deviated from the physical distancing measures. An online mixed-method study was conducted among Belgian adults (N = 2055) in the beginning of May 2020. Participants were recruited via an open call through email and social media platforms, using snowball sampling. Conditions wherein people deviated from the physical distancing measures were assessed by means of an open-ended question. HAPA determinants were assessed in a quantitative way. Half of the sample reported to deviate from the measures. Further, deviation from the measures was associated with each determinant outlined by the HAPA. Findings highlight that many people deviated from the measures because of their need for social contact. The majority of the people who deviated from the measures stated that they carefully weighed the risks of their behavior. Need for social contact pushed people to deviate from physical distancing measures in a deliberate manner. Potential areas for future interventions aimed at promoting adherence to physical distancing measures and enhancing psychosocial well-being are discussed. [less ▲]

Detailed reference viewed: 26 (0 UL)
Full Text
Peer Reviewed
See detailThe Mediation role of ADHD Symptoms and Emotion Regulation in the association between Executive functions and internalizing Symptoms: A study among youths with and without ADHD and/of Dyslexia
Battistutta, Layla; Schiltz, Christine UL; Steffgen, Georges UL

in Advances in Neurodevelopmental Disorders (2021), 5

Objectives The present study aimed at combining previous separate research findings having shown that executive functions (EF) contribute to a large range of emotional and behavioral problems among youths ... [more ▼]

Objectives The present study aimed at combining previous separate research findings having shown that executive functions (EF) contribute to a large range of emotional and behavioral problems among youths with and without neurodevelopmental disorders such as dyslexia and ADHD. Within a unifying framework, it investigated the mediational roles of ADHD symptoms and emotion regulation (ER) difficulties in the association between various EF and internalizing symptoms. Methods The sample included 82 adolescents with ADHD, dyslexia, comorbid ADHD/dyslexia, and typically developing adolescents, thus showing varying EF deficits. Whereas EF (attentional control, inhibition, shifting, working memory) were assessed in behavioral tasks, parents reported on ADHD symptoms, and ER and internalizing (anxiety, depression) symptoms were assessed via self-reports. Results In two-path mediation analyses, ADHD symptoms and ER problems mediated the association between working memory and anxiety (via inattention and ER, a1d21b2 = − .27, 95% CI [− .58, − .04]; via hyperactivity and ER, a1d21b2 = − .19, 95% CI [− .42, − .02]) and depression symptoms (via inattention and ER, a1d21b2 = − .20, 95% CI [− .54, − .03]; via hyperactivity and ER, a1d21b2 = − .24, 95% CI [− .48, − .03]). Hyperactivity and ER, but not inattention and ER, mediated the association between inhibition and internalizing symptoms (predicting anxiety, a1d21b2 = .003, 95% CI [.0001, .009]; predicting depression, a1d21b2 = .004, 95% CI [.002, .009]) as well as between attentional control and internalizing symptoms (predicting anxiety, a1d21b2 = .01, 95% CI [.001, .03]; predicting depression, a1d21b2 = .01, 95% CI [.004, .03]). Conclusions These results offer an insight into how ADHD symptoms and ER problems mediate the association between EF components and internalizing symptoms, with potential implications for prevention and intervention measures. [less ▲]

Detailed reference viewed: 64 (6 UL)
Full Text
Peer Reviewed
See detailHISTORIAE, History of Socio-Cultural Transformation as Linguistic Data Science. A Humanities Use Case
Armaselu, Florentina UL; Apostol, Elena-Simona; Khan, Anas Fahad et al

in Open Access Series in Informatics (2021), 93(2021), 341-3413

The paper proposes an interdisciplinary approach including methods from disciplines such as history of concepts, linguistics, natural language processing (NLP) and Semantic Web, to create a comparative ... [more ▼]

The paper proposes an interdisciplinary approach including methods from disciplines such as history of concepts, linguistics, natural language processing (NLP) and Semantic Web, to create a comparative framework for detecting semantic change in multilingual historical corpora and generating diachronic ontologies as linguistic linked open data (LLOD). Initiated as a use case (UC4.2.1) within the COST Action Nexus Linguarum, European network for Web-centred linguistic data science, the study will explore emerging trends in knowledge extraction, analysis and representation from linguistic data science, and apply the devised methodology to datasets in the humanities to trace the evolution of concepts from the domain of socio-cultural transformation. The paper will describe the main elements of the methodological framework and preliminary planning of the intended workflow. [less ▲]

Detailed reference viewed: 61 (8 UL)
Full Text
Peer Reviewed
See detailFunctional meta-omics provide critical insights into long- and short-read assemblies
Galata, Valentina UL; Busi, Susheel Bhanu UL; Kunath, Benoît UL et al

in Briefings in Bioinformatics (2021)

Real-world evaluations of metagenomic reconstructions are challenged by distinguishing reconstruction artifacts from genes and proteins present in situ. Here, we evaluate short-read-only, long-read-only ... [more ▼]

Real-world evaluations of metagenomic reconstructions are challenged by distinguishing reconstruction artifacts from genes and proteins present in situ. Here, we evaluate short-read-only, long-read-only and hybrid assembly approaches on four different metagenomic samples of varying complexity. We demonstrate how different assembly approaches affect gene and protein inference, which is particularly relevant for downstream functional analyses. For a human gut microbiome sample, we use complementary metatranscriptomic and metaproteomic data to assess the metagenomic data-based protein predictions. Our findings pave the way for critical assessments of metagenomic reconstructions. We propose a reference-independent solution, which exploits the synergistic effects of multi-omic data integration for the in situ study of microbiomes using long-read sequencing data. [less ▲]

Detailed reference viewed: 62 (6 UL)
Full Text
Peer Reviewed
See detailStress-induced inflammation evoked by immunogenic cell death is blunted by the IRE1α kinase inhibitor KIRA6 through HSP60 targeting
Rufo, Nicole; Korovesis, Dimitris; Van Eygen, Sofie et al

in Cell Death and Differentiation (2021)

Mounting evidence indicates that immunogenic therapies engaging the unfolded protein response (UPR) following endoplasmic reticulum (ER) stress favor proficient cancer cell-immune interactions, by ... [more ▼]

Mounting evidence indicates that immunogenic therapies engaging the unfolded protein response (UPR) following endoplasmic reticulum (ER) stress favor proficient cancer cell-immune interactions, by stimulating the release of immunomodulatory/ proinflammatory factors by stressed or dying cancer cells. UPR-driven transcription of proinflammatory cytokines/chemokines exert beneficial or detrimental effects on tumor growth and antitumor immunity, but the cell-autonomous machinery governing the cancer cell inflammatory output in response to immunogenic therapies remains poorly defined. Here, we profiled the transcriptome of cancer cells responding to immunogenic or weakly immunogenic treatments. Bioinformatics-driven pathway analysis indicated that immunogenic treatments instigated a NF-κB/AP-1-inflammatory stress response, which dissociated from both cell death and UPR. This stress-induced inflammation was specifically abolished by the IRE1α-kinase inhibitor KIRA6. Supernatants from immunogenic chemotherapy and KIRA6 co-treated cancer cells were deprived of proinflammatory/chemoattractant factors and failed to mobilize neutrophils and induce dendritic cell maturation. Furthermore, KIRA6 significantly reduced the in vivo vaccination potential of dying cancer cells responding to immunogenic chemotherapy. Mechanistically, we found that the anti-inflammatory effect of KIRA6 was still effective in IRE1α-deficient cells, indicating a hitherto unknown off-target effector of this IRE1α-kinase inhibitor. Generation of a KIRA6-clickable photoaffinity probe, mass spectrometry, and co-immunoprecipitation analysis identified cytosolic HSP60 as a KIRA6 off-target in the IKK-driven NF-κB pathway. In sum, our study unravels that HSP60 is a KIRA6-inhibitable upstream regulator of the NF-κB/AP-1-inflammatory stress responses evoked by immunogenic treatments. It also urges caution when interpreting the anti-inflammatory action of IRE1α chemical inhibitors. [less ▲]

Detailed reference viewed: 37 (2 UL)
Full Text
Peer Reviewed
See detailUAV Relay-Assisted Emergency Communications in IoT Networks: Resource Allocation and Trajectory Optimization
Tran Dinh, Hieu UL; Nguyen, van Dinh UL; Chatzinotas, Symeon UL et al

in IEEE Transactions on Wireless Communications (2021)

Unmanned aerial vehicle (UAV) communication hasemerged as a prominent technology for emergency communi-cations (e.g., natural disaster) in the Internet of Things (IoT)networks to enhance the ability of ... [more ▼]

Unmanned aerial vehicle (UAV) communication hasemerged as a prominent technology for emergency communi-cations (e.g., natural disaster) in the Internet of Things (IoT)networks to enhance the ability of disaster prediction, damageassessment, and rescue operations promptly. A UAV can bedeployed as a flying base station (BS) to collect data from time-constrained IoT devices and then transfer it to a ground gateway(GW). In general, the latency constraint at IoT devices and UAV’slimited storage capacity highly hinder practical applicationsof UAV-assisted IoT networks. In this paper, full-duplex (FD)radio is adopted at the UAV to overcome these challenges. Inaddition, half-duplex (HD) scheme for UAV-based relaying isalso considered to provide a comparative study between twomodes (viz., FD and HD). Herein, a device is considered tobe successfully served iff its data is collected by the UAV andconveyed to GW timely during flight time. In this context,we aim to maximize the number of served IoT devices byjointly optimizing bandwidth, power allocation, and the UAVtrajectory while satisfying each device’s requirement and theUAV’s limited storage capacity. The formulated optimizationproblem is troublesome to solve due to its non-convexity andcombinatorial nature. Towards appealing applications, we firstrelax binary variables into continuous ones and transform theoriginal problem into a more computationally tractable form.By leveraging inner approximation framework, we derive newlyapproximated functions for non-convex parts and then develop asimple yet efficient iterative algorithm for its solutions. Next,we attempt to maximize the total throughput subject to thenumber of served IoT devices. Finally, numerical results showthat the proposed algorithms significantly outperform benchmarkapproaches in terms of the number of served IoT devices andsystem throughput. [less ▲]

Detailed reference viewed: 76 (15 UL)
Full Text
Peer Reviewed
See detailGenotype-phenotype correlations in SCN8A-related disorders reveal prognostic and therapeutic implications
Johannesen, Katrine M.; Liu, Yuanyuan; Koko, Mahmoud et al

in Brain (2021)

We report detailed functional analyses and genotype-phenotype correlations in 392 individuals carrying disease-causing variants in SCN8A, encoding the voltage-gated Na+ channel NaV1.6, with the aim of ... [more ▼]

We report detailed functional analyses and genotype-phenotype correlations in 392 individuals carrying disease-causing variants in SCN8A, encoding the voltage-gated Na+ channel NaV1.6, with the aim of describing clinical phenotypes related to functional effects. Six different clinical subgroups could be identified: 1) Benign familial infantile epilepsy (BFIE) (n = 15, normal cognition, treatable seizures), 2) intermediate epilepsy (n = 33, mild ID, partially pharmaco-responsive), 3) developmental and epileptic encephalopathy (DEE, n = 177, severe ID, majority pharmaco-resistant), 4) generalized epilepsy (n = 20, mild to moderate ID, frequently with absence seizures), 5) unclassifiable epilepsy (n = 127), and 6) neurodevelopmental disorder without epilepsy (n = 20, mild to moderate ID). Groups 1–3 presented with focal or multifocal seizures (median age of onset: four months) and focal epileptiform discharges, whereas the onset of seizures in group 4 was later (median: 42 months) with generalized epileptiform discharges. We performed functional studies expressing missense variants in ND7/23 neuroblastoma cells and primary neuronal cultures using recombinant tetrodotoxin-insensitive human NaV1.6 channels and whole-cell patch-clamping. Two variants causing DEE showed a strong gain-of-function (GOF, hyperpolarising shift of steady-state activation, strongly increased neuronal firing rate), and one variant causing BFIE or intermediate epilepsy showed a mild GOF (defective fast inactivation, less increased firing). In contrast, all three variants causing generalized epilepsy induced a loss-of-function (LOF, reduced current amplitudes, depolarising shift of steady-state activation, reduced neuronal firing). Including previous studies, functional effects were known for 170 individuals. All 136 individuals carrying a functionally tested GOF variant had either focal (97, groups 1–3), or unclassifiable epilepsy (39), whereas 34 with a LOF variant had either generalized (14), no (11) or unclassifiable (6) epilepsy; only three had DEE. Computational modeling in the GOF group revealed a significant correlation between the severity of the electrophysiological and clinical phenotypes. GOF variant carriers responded significantly better to sodium channel blockers (SCBs) than to other anti-seizure medications, and the same applied for all individuals of groups 1–3.In conclusion, our data reveal clear genotype-phenotype correlations between age at seizure onset, type of epilepsy and gain- or loss-of-function effects of SCN8A variants. Generalized epilepsy with absence seizures is the main epilepsy phenotype of LOF variant carriers and the extent of the electrophysiological dysfunction of the GOF variants is a main determinant of the severity of the clinical phenotype in focal epilepsies. Our pharmacological data indicate that SCBs present a treatment option in SCN8A-related focal epilepsy with onset in the first year of life. [less ▲]

Detailed reference viewed: 50 (2 UL)
Full Text
Peer Reviewed
See detailRole of higher-order effects in spin-misalignment small-angle neutron scattering of high-pressure torsion nickel
Oba, Yojiro; Bersweiler, Mathias UL; Titov, Ivan et al

in Physical Review Materials (2021), 5

Detailed reference viewed: 25 (0 UL)
Full Text
Peer Reviewed
See detailNormative coherence for development – What relevance for responsive regionalism?
Koff, Harlan UL; Häbel, Sandra UL

in Development Policy Review (2021)

Without a normative dimension, transformative development risks reproducing traditional economic development. In this special issue we focus on norm implementation in different world regions through the ... [more ▼]

Without a normative dimension, transformative development risks reproducing traditional economic development. In this special issue we focus on norm implementation in different world regions through the lens of normative coherence for development. This special issue indicates that regions are an important interlocutor between the global, national, and sub-national level and, as such, are crucial for implementing the sustainable development agenda. The articles show, however, that to date normative coherence for development has not been achieved due to overriding priorities and technical approaches to policy coherence for development. With this special issue we aim to draw more attention to the topic of normative coherence for development and show that policies need to be adjusted in order to reflect the normative dimension of sustainable development. [less ▲]

Detailed reference viewed: 33 (0 UL)
Full Text
Peer Reviewed
See detailA Pharmacophore Model for SARS-CoV-2 3CLpro Small Molecule Inhibitors and in Vitro Experimental Validation of Computationally Screened Inhibitors
Glaab, Enrico UL; Manoharan, Ganesh Babu UL; Abankwa, Daniel UL

in Journal of Chemical Information and Modeling (2021), 61(8), 4082-4096

Among the biomedical efforts in response to the current coronavirus (COVID-19) pandemic, pharmacological strategies to reduce viral load in patients with severe forms of the disease are being studied ... [more ▼]

Among the biomedical efforts in response to the current coronavirus (COVID-19) pandemic, pharmacological strategies to reduce viral load in patients with severe forms of the disease are being studied intensively. One of the main drug target proteins proposed so far is the SARS-CoV-2 viral protease 3CLpro (also called Mpro), an essential component for viral replication. Ongoing ligand- and receptor-based computational screening efforts would be facilitated by an improved understanding of the electrostatic, hydrophobic and steric features that characterize small molecule inhibitors binding stably to 3CLpro, as well as by an extended collection of known binders. Here, we present combined virtual screening, molecular dynamics simulation, machine learning and in vitro experimental validation analyses which have led to the identification of small molecule inhibitors of 3CLpro with micromolar activity, and to a pharmacophore model that describes functional chemical groups associated with the molecular recognition of ligands by the 3CLpro binding pocket. Experimentally validated inhibitors using a ligand activity assay include natural compounds with available prior knowledge on safety and bioavailability properties, such as the natural compound rottlerin (IC50 = 37 µM), and synthetic compounds previously not characterized (e.g. compound CID 46897844, IC50 = 31 µM). In combination with the developed pharmacophore model, these and other confirmed 3CLpro inhibitors may provide a basis for further similarity-based screening in independent compound databases and structural design optimization efforts, to identify 3CLpro ligands with improved potency and selectivity. Overall, this study suggests that the integration of virtual screening, molecular dynamics simulations and machine learning can facilitate 3CLpro-targeted small molecule screening investigations. Different receptor-, ligand- and machine learning-based screening strategies provided complementary information, helping to increase the number and diversity of identified active compounds. Finally, the resulting pharmacophore model and experimentally validated small molecule inhibitors for 3CLpro provide resources to support follow-up computational screening efforts for this drug target. [less ▲]

Detailed reference viewed: 113 (10 UL)
Full Text
Peer Reviewed
See detailSoftware for the frontiers of quantum chemistry: An overview of developments in the Q-Chem 5 package
Evgeny Epifanovsky; Andrew T. B Gilbert; Xintian Feng et al

in Journal of Chemical Physics (2021)

Detailed reference viewed: 38 (1 UL)
Full Text
Peer Reviewed
See detailA research-practice cooperation to support elementary school teachers’ diagnostic competencies based on a working theory of talent development in STEM
Krischler, Mireille UL; Mack, Elena; Gnas, Jessica et al

in Gifted and Talented International (2021)

We present a teacher professionalization project for promoting elementary school teachers’ diagnostic competencies in recognizing their students’ potential in STEM subjects. Teacher professionalization is ... [more ▼]

We present a teacher professionalization project for promoting elementary school teachers’ diagnostic competencies in recognizing their students’ potential in STEM subjects. Teacher professionalization is fostered through the teachers’ personal involvement in the development of subjectspecific diagnostic materials as well as through continuing training on the fundamental knowledge needed to detect and support gifted students. On the basis of the Talent Development in Achievement Domains (TAD) framework, we reached a common working theory of talent and its development in mathematics and science for elementary school-aged students based on the available scientific evidence and approved by teachers. We share a multidimensional, dynamic view of talent development that includes abilities, personality traits, and skills. We describe how our working theory and diagnostic materials can foster teachers’ diagnostic competencies as well as talent discovery and promotion in order to foster students’ development of creative productivity in STEM fields. [less ▲]

Detailed reference viewed: 38 (0 UL)
Full Text
Peer Reviewed
See detailDistribution of kinks in an Ising ferromagnet after annealing and the generalized Kibble-Zurek mechanism
Mayo, Jack J.; Fan, Zhijie; Chern, Gia-Wei et al

in Physical Review Research (2021)

We consider the annealing dynamics of a one-dimensional Ising ferromagnet induced by a temperature quench in finite time. In the limit of slow cooling, the asymptotic two-point correlator is analytically ... [more ▼]

We consider the annealing dynamics of a one-dimensional Ising ferromagnet induced by a temperature quench in finite time. In the limit of slow cooling, the asymptotic two-point correlator is analytically found under Glauber dynamics, and the distribution of the number of kinks in the final state is shown to be consistent with a Poissonian distribution. The mean kink number, the variance, and the third centered moment take the same value and obey a universal power-law scaling with the quench time in which the temperature is varied. The universal power-law scaling of cumulants is corroborated by numerical simulations based on Glauber dynamics for moderate cooling times away from the asymptotic limit, when the kink-number distribution takes a binomial form. We analyze the relation of these results to physics beyond the Kibble-Zurek mechanism for critical dynamics, using the kink-number distribution to assess adiabaticity and its breakdown.We consider linear, nonlinear, and exponential cooling schedules, among which the last provides the most efficient shortcuts to cooling in a given quench time. The nonthermal behavior of the final state is established by considering the trace norm distance to a canonical Gibbs state. [less ▲]

Detailed reference viewed: 59 (1 UL)
Full Text
Peer Reviewed
See detail„Raum für Mehrsprachigkeit geben!“
Heinzel, Friederike; Schüler, Liz; Kirsch, Claudine UL et al

in Die Grundschulzeitschrift (2021)

Detailed reference viewed: 52 (1 UL)
Full Text
Peer Reviewed
See detailSchöne Digitale Welt: Analysen und Einsprüche (Rezension)
Baumann, Isabell Eva UL

in MEDIENwissenschaft: Rezensionen, Reviews (2021), 38(2),

Detailed reference viewed: 60 (7 UL)
Full Text
Peer Reviewed
See detailAlmost global convergence to practical synchronization in the generalized Kuramoto model on networks over the n-sphere
Markdahl, Johan UL; Proverbio, Daniele UL; Mi, La et al

in Communications Physics (2021), 4

From the flashing of fireflies to autonomous robot swarms, synchronization phenomena are ubiquitous in nature and technology. They are commonly described by the Kuramoto model that, in this paper, we ... [more ▼]

From the flashing of fireflies to autonomous robot swarms, synchronization phenomena are ubiquitous in nature and technology. They are commonly described by the Kuramoto model that, in this paper, we generalise to networks over n-dimensional spheres. We show that, for almost all initial conditions, the sphere model converges to a set with small diameter if the model parameters satisfy a given bound. Moreover, for even n, a special case of the generalized model can achieve phase synchronization with nonidentical frequency parameters. These results contrast with the standard n = 1 Kuramoto model, which is multistable (i.e., has multiple equilibria), and converges to phase synchronization only if the frequency parameters are identical. Hence, this paper shows that the generalized network Kuramoto models for n ≥ 2 displays more coherent and predictable behavior than the standard n = 1 model, a desirable property both in flocks of animals and for robot control. [less ▲]

Detailed reference viewed: 63 (1 UL)
See detailErgebnisse des Jugendberichtes 2020
Schumacher, Anette UL; S

in Ergebnisse des Jugendberichtes 2020 (2021)

Detailed reference viewed: 34 (6 UL)
Full Text
Peer Reviewed
See detailAutomatic Diagnosis of Bipolar Disorder Using Optical Coherence Tomography Data and Artificial Intelligence
Sanchez-Morla, Eva M.; Fuentes, Juan L.; Miguel-Jimenez et al

in Journal of Personalized Medicine (2021)

Background: The aim of this study is to explore an objective approach that aids the diagnosis of bipolar disorder (BD), based on optical coherence tomography (OCT) data which are analyzed using artificial ... [more ▼]

Background: The aim of this study is to explore an objective approach that aids the diagnosis of bipolar disorder (BD), based on optical coherence tomography (OCT) data which are analyzed using artificial intelligence. Methods: Structural analyses of nine layers of the retina were analyzed in 17 type I BD patients and 42 controls, according to the areas defined by the Early Treatment Diabetic Retinopathy Study (ETDRS) chart. The most discriminating variables made up the feature vector of several automatic classifiers: Gaussian Naive Bayes, K-nearest neighbors and support vector machines. Results: BD patients presented retinal thinning affecting most layers, compared to controls. The retinal thickness of the parafoveolar area showed a high capacity to discriminate BD subjects from healthy individuals, specifically for the ganglion cell (area under the curve (AUC) = 0.82) and internal plexiform (AUC = 0.83) layers. The best classifier showed an accuracy of 0.95 for classifying BD versus controls, using as variables of the feature vector the IPL (inner nasal region) and the INL (outer nasal and inner inferior regions) thickness. Conclusions: Our patients with BD present structural alterations in the retina, and artificial intelligence seem to be a useful tool in BD diagnosis, but larger studies are needed to confirm our findings. [less ▲]

Detailed reference viewed: 30 (1 UL)
Full Text
Peer Reviewed
See detailTowards a computer-assisted aesthetics of user response
Armaselu, Florentina UL

in Digital Scholarship in the Humanities (2021)

The article focuses on the analysis of the user as an aesthetic category and proposes a methodology for evaluating user response within a framework that combines theoretical background from different ... [more ▼]

The article focuses on the analysis of the user as an aesthetic category and proposes a methodology for evaluating user response within a framework that combines theoretical background from different areas, the theory of aesthetic response, psycholinguistics, appraisal theory, dialogism, and affective stylistics, with the application of digital tools for corpus linguistics and sentiment analysis. Four user types were derived from the corpus linguistics analysis referred to as immersed, distant, sceptical, and enthusiastic users. Each type may encompass a certain degree of intentionality and convey an attitude, implying features such as commitment and honesty, objectivity and engagement with the audience, critical reflection and circumspection, openness to technological novelty, and enjoyment. This assumes that the users involved in usability testing are not neutral or undifferentiated informational entities placed in an experimental context but individuals that respond to the same stimuli and express themselves differently in light of psycholinguistic factors and rules of social interaction. On the other hand, the results of sentiment analysis showed that an experiential analysis, centred not only on the artefact but also on the response and the experience it generates, may enable understanding the user as involved in a hermeneutic process of interpretation during his/her interaction with the studied artefact. Given the small scale of the analysed data, the study does not intend to provide evidence for general or definitive statements but formulates and illustrates a set of interpretative hypotheses and methodological directions for further enquiry aiming at developing an ‘aesthetics’ of user response. [less ▲]

Detailed reference viewed: 147 (16 UL)
Full Text
Peer Reviewed
See detailRole of S100A8/A9 for Cytokine Secretion, Revealed in Neutrophils Derived from ER-Hoxb8 Progenitors
Zhou, Yang UL; Hann, Justine UL; Schenten, Veronique UL et al

in International Journal of Molecular Sciences (2021)

S100A9, a Ca2+-binding protein, is tightly associated to neutrophil pro-inflammatory functions when forming a heterodimer with its S100A8 partner. Upon secretion into the extracellular environment, these ... [more ▼]

S100A9, a Ca2+-binding protein, is tightly associated to neutrophil pro-inflammatory functions when forming a heterodimer with its S100A8 partner. Upon secretion into the extracellular environment, these proteins behave like damage-associated molecular pattern molecules, which actively participate in the amplification of the inflammation process by recruitment and activation of pro-inflammatory cells. Intracellular functions have also been attributed to the S100A8/A9 complex, notably its ability to regulate nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activation. However, the complete functional spectrum of S100A8/A9 at the intracellular level is far from being understood. In this context, we here investigated the possibility that the absence of intracellular S100A8/A9 is involved in cytokine secretion. To overcome the difficulty of genetically modifying neutrophils, we used murine neutrophils derived from wild-type and S100A9-/- Hoxb8 immortalized myeloid progenitors. After confirming that differentiated Hoxb8 neutrophil-like cells are a suitable model to study neutrophil functions, our data show that absence of S100A8/A9 led to a dysregulation of cytokine secretion after lipopolysaccharide (LPS) stimulation. Furthermore, we demonstrate that S100A8/A9-induced cytokine secretion was regulated by the nuclear factor kappa B (NF-κB) pathway. These results were confirmed in human differentiated HL-60 cells, in which S100A9 was inhibited by shRNAs. Finally, our results indicate that the degranulation process could be involved in the regulation of cytokine secretion by S100A8/A9. [less ▲]

Detailed reference viewed: 64 (8 UL)
Full Text
Peer Reviewed
See detailA Catalogus Immune Muris of the mouse immune responses to diverse pathogens
Del Sol Mesa, Antonio UL

in Cell Death and Disease (2021)

Detailed reference viewed: 69 (7 UL)
Full Text
Peer Reviewed
See detailRobustness of Adversarial Images against Filters
Chitic, Ioana Raluca UL; Deridder, Nathan; Leprevost, Franck UL et al

in Optimization and Learning (2021), 1443

Detailed reference viewed: 65 (2 UL)
Full Text
Peer Reviewed
See detailNumerical study on design rules for minimum degree of shear connection in propped steel-concrete composite beams
Vigneri, Valentino; Odenbreit, Christoph UL; Romero, Alfredo UL

in Engineering Structures (2021), 241

This manuscript presents a numerical study on simply supported propped composite beams with ductile shear connectors subjected to uniformly distributed load. The aim is to assess the performance of the ... [more ▼]

This manuscript presents a numerical study on simply supported propped composite beams with ductile shear connectors subjected to uniformly distributed load. The aim is to assess the performance of the revised rules for the minimum degree of shear connection (CEN/TC250/SC4.T3) with respect to the occurring slip. First, a non-linear 3D finite element model was developed through the software ABAQUS 2017 and validated against analytical values of the elastic stiffness and plastic bending resistance. Then, 91 configurations were analysed for different degrees of shear connection η=0.2,0.4…1.0. The span ranges from 6 to 25 m while the geometrical and mechanical properties varied within their typical field of applicability. According to both current and revised rules, 16 configurations with relatively deep beam and “weak” concrete slab exhibited allowable slip values smax significantly higher than 6 m. Therefore, the authors proposed a reduction of the maximum degree of utilization to these special cases. If the proposed reduction is included in the revised rules, none of the considered cases exhibit a slip smax higher than 8 mm while few cases have smax between 6 and 8 mm. For the ease of use, a design proposal is reformulated as a conditional reduction of the plastic bending resistance of the composite section. [less ▲]

Detailed reference viewed: 141 (11 UL)
Full Text
Peer Reviewed
See detailWideband OFDM-based Communications in Bus Topology as a Key Enabler for Industry 4.0 Networks
Gonzalez Rios, Jorge Luis UL; Torres Gómez, Jorge; Sharma, Rajesh Kumar et al

in IEEE Access (2021), 9

The Industry 4.0 paradigm conceives a cyber-physical supporting framework for the manufacturing processes in smart factories. In this context, solutions concerning the wired communications at the field ... [more ▼]

The Industry 4.0 paradigm conceives a cyber-physical supporting framework for the manufacturing processes in smart factories. In this context, solutions concerning the wired communications at the field-level have been reported which utilize either fieldbuses, which exhibit a huge distance range but a reduced data rate in a bus topology, or Ethernet-based technologies, which provide an increased data rate but reduced distance in a ring topology. To overcome this shortage, we propose the use of orthogonal frequency division multiplexing (OFDM) to significantly increase the achievable data rates over large distances in industrial bus systems. Also, we establish a novel methodology to compute the signal-to-noise ratio between arbitrary pairs of nodes, which in turn allows to compute the communication capacity. Our wideband system was validated by connecting up to 32 nodes in the distance range 100 m–1 km. Compared to fieldbuses, the results of the proposal exhibit an amazing improvement in data rate of about fifty times for 100m distance and more than ten times for 0.5 km. Moreover, with respect to Ethernet-based solutions, the results show a relevant improvement in the data rate of around five times for 100 m distance, but Ethernet-based systems cannot go beyond this distance, to which our proposal is not limited. [less ▲]

Detailed reference viewed: 81 (11 UL)
Full Text
Peer Reviewed
See detailCharacterizing the Theory of Spreading Electric Vehicles in Luxembourg
Arababadi; Leyer, Stephan UL; Leyer, Stephan UL et al

in Sustainability (2021)

Detailed reference viewed: 39 (0 UL)
Full Text
Peer Reviewed
See detailIntelligent Reflecting Surface Enhanced Secure Transmission Against Both Jamming and Eavesdropping Attacks
Sun, Yifu; An, Kang; Luo, Junshan et al

in IEEE Transactions on Vehicular Technology (2021), 70(10, Oct. 2021), 11017-11022

Both the jammer and the eavesdropper pose severe threat to wireless communications due to the broadcast nature of wireless channels. In this paper, an intelligent reflecting surface (IRS) assisted secure ... [more ▼]

Both the jammer and the eavesdropper pose severe threat to wireless communications due to the broadcast nature of wireless channels. In this paper, an intelligent reflecting surface (IRS) assisted secure communication system is considered, where a base station (BS) wishes to reliably convey information to a user, in the presence of both a jammer and an eavesdropper whose channel state information (CSI) is not perfectly known. Specifically, we aim to maximize the system achievable rate by jointly designing the BS’s transmit beamforming and the IRS’s reflect beamforming with imperfect CSI, while limiting the information leakage to the potential eavesdropper. Due to the non-convexity and intractability of the original problem induced by the CSI uncertainty, we utilize the auxiliary variables and General Sign-Definiteness transformation to convert the original optimization problem into a tractable convex optimization problem, and then obtain the high-quality optimal solution by using the successive convex approximation and penalty convex concave procedure. Numerical simulations demonstrate the superiority of our proposed optimization algorithm compared with existing approaches, and also reveal the impact of key parameters on the achievable system performance. [less ▲]

Detailed reference viewed: 26 (1 UL)
Full Text
Peer Reviewed
See detailATG5 and ATG7 Expression Levels Are Reduced in Cutaneous Melanoma and Regulated by NRF1
Frangez, Ziva; Gerard, Déborah UL; He, Zhahoyue et al

in Frontiers in Oncology (2021)

Detailed reference viewed: 34 (2 UL)
Full Text
Peer Reviewed
See detailPsychological wellbeing of parents of very young children with type 1 diabetes – baseline assessment
De Beaufort, Carine; Pit-Ten Cate, Ineke UL; Schierloh, Ulrike et al

in Frontiers in Endocrinology (2021), 12(721028),

Background: Type 1 diabetes in young children is a heavy parental burden. As part of pilot phase of the KIDSAP01 study, we conducted a baseline assessment in parents to study the association between ... [more ▼]

Background: Type 1 diabetes in young children is a heavy parental burden. As part of pilot phase of the KIDSAP01 study, we conducted a baseline assessment in parents to study the association between hypoglycemia fear, parental wellbeing and child behavior. Methods: All parents were invited to fill in baseline questionnaires: hypoglycemia fear survey (HFS), WHO-5, Epworth Sleepiness Scale and Strength and Difficulties Questionnaire (SDQ). Results: 24 children (median age: 5-year, range 1-7 years, 63% male, mean diabetes duration: 3 ± 1.7 years) participated. 23/24 parents filled out the questionnaires. We found a higher score for the hypoglycemia fear behavior 33.9 ± 5.6 compared to hypoglycemia worry 34.6 ± 12.2. Median WHO-5 score was 16 (8 - 22) with poor well-being in two parents. Median daytime sleepiness score was high in five parents (>10). For six children a high total behavioral difficulty score (>16) was reported. Pro social behavior score was lower than normal in six children (<6). Parental well-being was negatively associated with HFS total (r = - 0.50, p <.05) and subscale scores (r = - 0.44, p <.05 for HFS-Worry and HFS-Behavior), child behavior (r = - 0.45, p = .05) and positively with child age (r = 0.58, p <.01). HFS, parental well-being nor daytime sleepiness are associated with the HbA1c. Conclusion: Regular screening of parental well-being, hypoglycemia fear and child behavior should be part of routine care to target early intervention. [less ▲]

Detailed reference viewed: 65 (6 UL)
Full Text
Peer Reviewed
See detailRandomization as Mitigation of Directed Timing Inference Based Attacks on Time-Triggered Real-Time Systems with Task Replication
Krüger, Kristin; Vreman, Nils; Pates, Richard et al

in LITES: Leibnitz Transactions on Embedded Systems (2021)

Time-triggered real-time systems achieve deterministic behavior using schedules that are constructed offline, based on scheduling constraints. Their deterministic behavior makes time-triggered systems ... [more ▼]

Time-triggered real-time systems achieve deterministic behavior using schedules that are constructed offline, based on scheduling constraints. Their deterministic behavior makes time-triggered systems suitable for usage in safety-critical environments, like avionics. However, this determinism also allows attackers to fine-tune attacks that can be carried out after studying the behavior of the system through side channels, targeting safety-critical victim tasks. Replication – i.e., the execution of task variants across different cores – is inherently able to tolerate both accidental and malicious faults (i.e. attacks) as long as these faults are independent of one another. Yet, targeted attacks on the timing behavior of tasks which utilize information gained about the system behavior violate the fault independence assumption fault tolerance is based on. This violation may give attackers the opportunity to compromise all replicas simultaneously, in par- ticular if they can mount the attack from already compromised components. In this paper, we ana- lyze vulnerabilities of time-triggered systems, focusing on safety-certified multicore real-time systems. We introduce two runtime mitigation strategies to withstand directed timing inference based attacks: (i) schedule randomization at slot level, and (ii) randomization within a set of offline constructed schedules. We evaluate these mitigation strategies with synthetic experiments and a real case study to show their effectiveness and practicality. [less ▲]

Detailed reference viewed: 68 (5 UL)
Full Text
Peer Reviewed
See detailA Comparative Study of Thermoelectric Properties of Monolayer, Bilayer and Bulk CrI3
Suprayoga, E; Hanna, M. Y.; Hasdeo, Eddwi Hesky UL et al

in AIP Conference Proceedings (2021), 2382(1), 020004

We comparatively study the electronic and thermoelectric properties of the monolayer, bilayer, and bulk CrI3 by density functional theory (DFT). We show that, according to the DFT calculation, those ... [more ▼]

We comparatively study the electronic and thermoelectric properties of the monolayer, bilayer, and bulk CrI3 by density functional theory (DFT). We show that, according to the DFT calculation, those materials are magnetic semiconductors with ferromagnetic (FM) in monolayer, antiferromagnetic (AFM) in the bilayer, back to FM in the bulk structure. The thermoelectric properties of those materials are evaluated by using the Boltzmann transport equation (BTE) with a constant relaxation time approximation (RTA). At room temperature, we obtain bulk CrI3 has more significant electrical conductivity than monolayer and bilayer CrI3, while the Seebeck coefficient is similar that implied the bulk CrI3 has a better thermoelectric performance. In those systems, the optimum power factor is obtained by shifting the chemical potential of CrI3 by 1 eV with p-type doping. [less ▲]

Detailed reference viewed: 34 (1 UL)
Full Text
Peer Reviewed
See detailQuantitative trait locus mapping identifies a locus linked to striatal dopamine and points to collagen IV alpha-6 chain as a novel regulator of striatal axonal branching in mice
Thomas, Melanie UL; Gui, Yujuan; Garcia, Pierre UL et al

in Genes, Brain, and Behavior (2021)

Dopaminergic neurons (DA neurons) are controlled by multiple factors, many involved in neurological disease. Parkinson's disease motor symptoms are caused by the demise of nigral DA neurons, leading to ... [more ▼]

Dopaminergic neurons (DA neurons) are controlled by multiple factors, many involved in neurological disease. Parkinson's disease motor symptoms are caused by the demise of nigral DA neurons, leading to loss of striatal dopamine (DA). Here, we measured DA concentration in the dorsal striatum of 32 members of Collaborative Cross (CC) family and their eight founder strains. Striatal DA varied greatly in founders, and differences were highly heritable in the inbred CC progeny. We identified a locus, containing 164 genes, linked to DA concentration in the dorsal striatum on chromosome X. We used RNAseq profiling of the ventral midbrain of two founders with substantial difference in striatal DA–C56BL/6 J and A/J—to highlight potential protein-coding candidates modulating this trait. Among the five differentially expressed genes within the locus, we found that the gene coding for the collagen IV alpha 6 chain (Col4a6) was expressed nine times less in A/J than in C57BL/6J. Using single cell RNA-seq data from developing human midbrain, we found that COL4A6 is highly expressed in radial glia-like cells and neuronal progenitors, indicating a role in neuronal development. Collagen IV alpha-6 chain (COL4A6) controls axogenesis in simple model organisms. Consistent with these findings, A/J mice had less striatal axonal branching than C57BL/6J mice. We tentatively conclude that DA concentration and axonal branching in dorsal striatum are modulated by COL4A6, possibly during development. Our study shows that genetic mapping based on an easily measured Central Nervous System (CNS) trait, using the CC population, combined with follow-up observations, can parse heritability of such a trait, and nominate novel functions for commonly expressed proteins. [less ▲]

Detailed reference viewed: 23 (2 UL)
Full Text
Peer Reviewed
See detailMachine learning-based identification and characterization of 15 novel pathogenic SUOX missense mutations
Kaczmarek, Alexander Tobias; Bahlmann, Nike; Thaqi, Besarta et al

in Molecular Genetics and Metabolism (2021)

Isolated sulfite oxidase deficiency (ISOD) is a rare hereditary metabolic disease caused by absence of functional sulfite oxidase (SO) due to mutations of the SUOX gene. SO oxidizes toxic sulfite and ... [more ▼]

Isolated sulfite oxidase deficiency (ISOD) is a rare hereditary metabolic disease caused by absence of functional sulfite oxidase (SO) due to mutations of the SUOX gene. SO oxidizes toxic sulfite and sulfite accumulation is associated with neurological disorders, progressive brain atrophy and early death. Similarities of these neurological symptoms to abundant diseases like neonatal encephalopathy underlines the raising need to increase the awareness for ISOD. Here we report an interdisciplinary approach utilizing exome/genome data derived from gnomAD database as well as published variants to predict the pathogenic outcome of 303 naturally occurring SO missense variants and combining these with activity determination. We identified 15 novel ISOD-causing SO variants and generated a databank of pathogenic SO missense variants to support future diagnosis of ISOD patients. We found six inactive variants (W101G, H118Y, E197K, R217W, S427W, D512Y, Q518R) and seven (D110H, P119S, G121E, G130R, Y140C, R269H, Q396P, R459Q) with severe reduction in activity. Based on the Hardy-Weinberg-equilibrium and the combination of our results with published SO missense and protein truncating variants, we calculated the first comprehensive incidence rate for ISOD of 1 in 1,377,341 births and provide a pathogenicity score to 303 naturally occurring SO missense variants. [less ▲]

Detailed reference viewed: 55 (4 UL)
Full Text
Peer Reviewed
See detailWhat accounts for changes in the chances of being NEET in the UK?
Holmes, Craig; Murphy, Emily UL; Mayhew, Ken

in Journal of Education and Work (2021)

Detailed reference viewed: 52 (0 UL)
Full Text
Peer Reviewed
See detailMassive MIMO under Double Scattering Channels: Power Minimization and Congestion Controls
Van Chien, Trinh; Ngo, Hien Quoc; Chatzinotas, Symeon UL et al

in IEEE Transactions on Wireless Communications (2021)

This paper considers a massive MIMO system under the double scattering channels. We derive a closed-form expression of the uplink ergodic spectral efficiency (SE) by exploiting the maximum-ratio combining ... [more ▼]

This paper considers a massive MIMO system under the double scattering channels. We derive a closed-form expression of the uplink ergodic spectral efficiency (SE) by exploiting the maximum-ratio combining technique with imperfect channel state information. We then formulate and solve a total uplink data power optimization problem that aims at simultaneously satisfying the required SEs from all the users with limited power resources. We further propose algorithms to cope with the congestion issue appearing when at least one user is served by lower SE than requested. Numerical results illustrate the effectiveness of our proposed power optimization. More importantly, our proposed congestion-handling algorithms can guarantee the required SEs to many users under congestion, even when the SE requirement is high. [less ▲]

Detailed reference viewed: 27 (1 UL)
Full Text
Peer Reviewed
See detailA rigged model of the breast for preoperative surgical planning
Mazier, Arnaud UL; Ribes, Sophie; Gilles, Benjamin et al

in Journal of Biomechanics (2021), 128

In breast surgical practice, drawing is part of the preoperative planning procedure and is essential for a successful operation. In this study, we design a pipeline to assist surgeons with patient ... [more ▼]

In breast surgical practice, drawing is part of the preoperative planning procedure and is essential for a successful operation. In this study, we design a pipeline to assist surgeons with patient-specific breast surgical drawings. We use a deformable torso model containing the surgical patterns to match any breast surface scan. To be compatible with surgical timing, we build an articulated model through a skinning process coupled with shape deformers to enhance a fast registration process. On one hand, the scalable bones of the skinning account for pose and morphological variations of the patients. On the other hand, pre-designed artistic blendshapes create a linear space for guaranteeing anatomical variations. Then, we apply meaningful constraints to the model to find a trade-off between precision and speed. The experiments were conducted on 7 patients, in 2 different poses (prone and supine) with a breast size ranging from 36A and 42C (US/UK bra sizing). The acquisitions were obtained using the depth camera Structure Sensor, and the breast scans were acquired in less than 1 minute. The result is a registration method converging within a few seconds (3 maximum), reaching a Mean Absolute Error of 2.3 mm for mesh registration and 8.0 mm for breast anatomical landmarks. Compared to the existing literature, our model can be personalized and does not require any database. Finally, our registered model can be used to transfer surgical reference patterns onto any patient in any position. [less ▲]

Detailed reference viewed: 94 (13 UL)
Full Text
Peer Reviewed
See detailFailure mechanism analysis based on laser-based surface treatments for aluminum-polyamide laser joining
Amne Elahi, Mahdi UL; Koch, Marcus; Bardon, Julien et al

in Journal of Materials Processing Technology (2021), 298

The development of strong metal to polymer assemblies is currently an important research subject thanks to its prominence to develop lightweight structures. Furthermore, laser welding is known to be a ... [more ▼]

The development of strong metal to polymer assemblies is currently an important research subject thanks to its prominence to develop lightweight structures. Furthermore, laser welding is known to be a fast, reliable, and versatile joining process, and it was demonstrated recently that it can be applied to such metal to polymer systems. To enhance the mechanical properties of the laser-joined aluminum-polyamide (Al-PA) specimens, laser polishing and laser ablation processes have been implemented on the aluminum surface before joining. The polyamide surface was also treated with the laser beam, separately. The surfaces were tested by several characterization techniques before and after each surface treatment. Then aluminum and polyamide samples with different surface treatments have been joined with an identical laser joining process. The mechanical properties of the joints in single lap shear configuration are reported and the failure mechanisms are discussed based on micro-computed x-ray tomography imaging of joined specimens and microscopic analysis before failure. Results show that both surface treatments of aluminum significantly improve the shear load of the joint; however, with different failure mechanisms. Polyamide surface treatment and increasing degree of crystallinity are effective when combined with the laser polishing of the Al surface. This combination is responsible for further enhancement of the shear load of the joint to the limit of base metal strength which is approximately 60 % improvement compared to the untreated samples. Finally, energy dispersive X-ray mapping shows the physicochemical bonding between aluminum oxide and polyamide at the interface. [less ▲]

Detailed reference viewed: 49 (5 UL)
Full Text
Peer Reviewed
See detailSimulation of gas-dynamic, pressure surges and adiabatic compression phenomena in geometrically complex respirator oxygen valves
Obeidat, Anas UL; Andreas, Thomas; Bordas, Stéphane UL et al

in Thermal Science and Engineering Progress (2021), 24

Gas-dynamic pressure surges and adiabatic compression phenomena are generally hard to predict numerically. In this contribution, we study the effect of the pressure reserve capacity on the compressible ... [more ▼]

Gas-dynamic pressure surges and adiabatic compression phenomena are generally hard to predict numerically. In this contribution, we study the effect of the pressure reserve capacity on the compressible gas-dynamics pressure surge and adiabatic compression in a fitted respirator oxygen valve geometry. A three-dimensional remeshed smoothed particle hydrodynamics method for the simulation of isotropic turbulence is used, the method is coupled with Brinkman penalisation technique for flow simulation inside the complex valve geometry. Simulations are carried out for three different pressure reserve quantities, to replicate the opening of the valve, two time-based pressure inlet boundary condition functions were simulated along with an impulsively started scenario. A geometrical sensitivity analysis is provided, where the simulation is performed on a modified valve design which exhibits a damping effect on the gas dynamics and flow characteristics, which has a favourable effect on the valve functionality and safety. It is found that the capacity of the pressure reserve has a considerable effect on the simulated flow fields (velocity, temperature), as the temperature could rise 6.0X the reference temperature, and up to 2.7X the reference velocity. The numerical results are compared with a previous study carried out by Rotarex S.A., demonstrating that the remeshed particle-mesh method coupled with Brinkman penalisation provides a good quality simulation and the results are in agreement with the reference solution. [less ▲]

Detailed reference viewed: 68 (9 UL)
Full Text
Peer Reviewed
See detailSupervised machine learning for power and bandwidth management in very high throughput satellite systems
Ortiz Gomez, Flor de Guadalupe UL; Tarchi, Daniele; Martinez, Ramon et al

in International Journal of Satellite Communications and Networking (2021)

In the near future, very high throughput satellite (VHTS) systems are expected to have a high increase in traffic demand. However, this increase will not be uniform over the service area and will be also ... [more ▼]

In the near future, very high throughput satellite (VHTS) systems are expected to have a high increase in traffic demand. However, this increase will not be uniform over the service area and will be also dynamic. A solution to this problem is given by flexible payload architectures; however, they require that resource management is performed autonomously and with low latency. In this paper, we propose the use of supervised machine learning, in particular a classification algorithm using a neural network, to manage the resources available in flexible payload architectures. Use cases are presented to demonstrate the effectiveness of the proposed approach, and a discussion is made on all the challenges that are presented. [less ▲]

Detailed reference viewed: 26 (5 UL)
Full Text
Peer Reviewed
See detailWhen a Master Dies: Speculation and Asset Float
Penasse, Julien UL; Renneboog, Luc; Scheinkman, José

in Review of Financial Studies (2021), 34(8), 38403879

Detailed reference viewed: 56 (1 UL)
Full Text
Peer Reviewed
See detailGuest Editorial: Space Information Networks: Technological Challenges, Design Issues, and Solutions
Xue, Kaiping; De Cola, Tomaso; Wei, David S.L. et al

in IEEE Network (2021), 35(4), 16-18

It has been expected that the space information networks (SIN), as an extension of the terrestrial network, would provide high-speed, high-capacity, global continuous communication, and data transmission ... [more ▼]

It has been expected that the space information networks (SIN), as an extension of the terrestrial network, would provide high-speed, high-capacity, global continuous communication, and data transmission services anywhere for anyone at any time. With rapid advances in relevant technologies (e.g., satellite miniaturization technology, reusable rocket launch technology, and semiconductor technology), low-orbit satellites, drones, and airships can be integrated into the SIN to supply more comprehensive network connectivity. The standard development organizations including 3GPP, ITU, and ETSI already starts corresponding standardization activities to support nonterrestrial networks in SIN. It can be foreseen that SIN will be expanded to provide not only telephone services but also various kinds of Internet services, and it is thus able to serve many more users with different demands. [less ▲]

Detailed reference viewed: 26 (1 UL)
Full Text
Peer Reviewed
See detailOutage Probability Analysis of IRS-Assisted Systems Under Spatially Correlated Channels
Trinh, van Chien UL; K. Papazafeiropoulos, Anastasios; Tu, Lam Thanh et al

in IEEE Wireless Communications Letters (2021), 10(8), 1815-1819

This paper investigates the impact of spatial channel correlation on the outage probability of intelligent reflecting surface (IRS)-assisted single-input single-output (SISO) communication systems. In ... [more ▼]

This paper investigates the impact of spatial channel correlation on the outage probability of intelligent reflecting surface (IRS)-assisted single-input single-output (SISO) communication systems. In particular, we derive a novel closed-form expression of the outage probability for arbitrary phase shifts and correlation matrices of the indirect channels. To shed light on the impact of the spatial correlation, we further attain the closed-form expressions for two common scenarios met in the literature when the large-scale fading coefficients are expressed by the loss over a propagation distance. Numerical results validate the tightness and effectiveness of the closed-form expressions. Furthermore, the spatial correlation offers significant decreases in the outage probability as the direct channel is blocked. [less ▲]

Detailed reference viewed: 55 (1 UL)
Full Text
Peer Reviewed
See detail"Unless One Does the Research, It May Seem as Just a Useless Battery-Consuming App" - Field Notes on COVID-19 Contact Tracing Applications
Stojkovski, Borce UL; Abu-Salma, Ruba; Triquet, Karen et al

in Digital Threats: Research and Practice (2021)

Globally, countries have been developing contact tracing applications to control the spread of the Coronavirus (COVID-19) disease. In this work, we present the findings of eight focus groups we conducted ... [more ▼]

Globally, countries have been developing contact tracing applications to control the spread of the Coronavirus (COVID-19) disease. In this work, we present the findings of eight focus groups we conducted with participants living in France and Germany, to explore why they decided to adopt, or not adopt, a contact tracing application as well as understand how they perceived the benefits/drawbacks and the threat model of a contact tracing application. [less ▲]

Detailed reference viewed: 30 (1 UL)
Full Text
Peer Reviewed
See detail1918, 1945, 1989: Childhood in Times of Political Transformation: Part II
Kind-Kovács, Friederike; Venken, Machteld UL

in Journal of Modern European History (2021), 19

Detailed reference viewed: 26 (0 UL)
Full Text
See detailEditoriaal. Kinderen.
Venken, Machteld UL

in Tijdschrift. Erfgoedpraktijk in Vlaanderen (2021), 11(2), 4-5

Detailed reference viewed: 18 (3 UL)
Full Text
Peer Reviewed
See detailPolicy Experimentation in Committees: A Case Against Veto Rights Under Redistributive Constraints
Anesi, Vincent UL; Bowen, Renee

in American Economic Journal. Microeconomics (2021), 13(3), 124-162

We study optimal policy experimentation by a committee. We consider a dynamic bargaining game in which committee members choose either a risky reform or a safe alternative each period. When no ... [more ▼]

We study optimal policy experimentation by a committee. We consider a dynamic bargaining game in which committee members choose either a risky reform or a safe alternative each period. When no redistribution is allowed the unique equilibrium outcome is generically inefficient. When redistribution is allowed (even small amounts), there always exists an equilibrium that supports optimal experimentation for any voting rule without veto players. With veto players, however, optimal policy experimentation is possible only with a sufficient amount of redistribution. We conclude that veto rights are more of an obstacle to optimal policy experimentation than the constraints on redistribution themselves. [less ▲]

Detailed reference viewed: 64 (2 UL)
Full Text
Peer Reviewed
See detailCreativity in Humans, Robots, Humbots
Lubart, Todd; Esposito, Dario; Gubenko, Alla UL et al

in Creativity: Theories – Research – Applications (2021), 8(1),

Detailed reference viewed: 50 (8 UL)
Full Text
Peer Reviewed
See detailOn The (In)Effectiveness of Static Logic Bomb Detector for Android Apps
Samhi, Jordan UL; Bartel, Alexandre UL

in IEEE Transactions on Dependable and Secure Computing (2021)

Android is present in more than 85% of mobile devices, making it a prime target for malware. Malicious code is becoming increasingly sophisticated and relies on logic bombs to hide itself from dynamic ... [more ▼]

Android is present in more than 85% of mobile devices, making it a prime target for malware. Malicious code is becoming increasingly sophisticated and relies on logic bombs to hide itself from dynamic analysis. In this paper, we perform a large scale study of TSO PEN, our open-source implementation of the state-of-the-art static logic bomb scanner T RIGGER S COPE, on more than 500k Android applications. Results indicate that the approach scales. Moreover, we investigate the discrepancies and show that the approach can reach a very low false-positive rate, 0.3%, but at a particular cost, e.g., removing 90% of sensitive methods. Therefore, it might not be realistic to rely on such an approach to automatically detect all logic bombs in large datasets. However, it could be used to speed up the location of malicious code, for instance, while reverse engineering applications. We also present T RIGDB a database of 68 Android applications containing trigger-based behavior as a ground-truth to the research community. [less ▲]

Detailed reference viewed: 37 (2 UL)
Full Text
Peer Reviewed
See detailRethinking Trust in Social Robotics
Carli, Rachele UL; Najjar, Amro UL

in arXiv (2021)

— In 2018 the European Commission highlighted the demand of a human-centered approach to AI. Such a claim is gaining even more relevance considering technologies specifi cally designed to directly ... [more ▼]

— In 2018 the European Commission highlighted the demand of a human-centered approach to AI. Such a claim is gaining even more relevance considering technologies specifi cally designed to directly interact and physically collaborate with human users in the real world. This is notably the case of social robots. The domain of Human-Robot Interaction (HRI) emerged to investigate these issues."Human-robot trust" has been highlighted as one of the most challenging and intriguing factors influencing HRI. On the one hand, user studies and technical experts underline how trust is a key element to facilitate users’ acceptance, consequently increasing the chances to pursue the given task. On the other hand, such a phenomenon raises also ethical and philosophical concerns leading scholars in these domains to argue that humans should not trust robots. However, trust in HRI is not an index of fragility, it is rooted in anthropomorphism, and it is a natural characteristic of every human being. Thus, instead of focusing solely on how to inspire user trust in social robots, this paper argues that what should be investigated is to what extent and for which purpose it is suitable to trust robots. Such an endeavour requires an interdisciplinary approach taking into account (i) technical needs and (ii) psychological implications. [less ▲]

Detailed reference viewed: 17 (2 UL)
Full Text
Peer Reviewed
See detailModelling COVID-19 dynamics and potential for herd immunity by vaccination in Austria, Luxembourg and Sweden
Kemp, Francoise UL; Proverbio, Daniele UL; Aalto, Atte UL et al

in Journal of Theoretical Biology (2021)

Against the COVID-19 pandemic, non-pharmaceutical interventions have been widely applied and vaccinations have taken off. The upcoming question is how the interplay between vaccinations and social ... [more ▼]

Against the COVID-19 pandemic, non-pharmaceutical interventions have been widely applied and vaccinations have taken off. The upcoming question is how the interplay between vaccinations and social measures will shape infections and hospitalizations. Hence, we extend the Susceptible-Exposed-Infectious-Removed (SEIR) model including these elements. We calibrate it to data of Luxembourg, Austria and Sweden until 15 December 2020. Sweden results having the highest fraction of undetected, Luxembourg of infected and all three being far from herd immunity in December. We quantify the level of social interaction, showing that a level around 1/3 of before the pandemic was still required in December to keep the effective reproduction number Refft below 1, for all three countries. Aiming to vaccinate the whole population within 1 year at constant rate would require on average 1,700 fully vaccinated people/day in Luxembourg, 24,000 in Austria and 28,000 in Sweden, and could lead to herd immunity only by mid summer. Herd immunity might not be reached in 2021 if too slow vaccines rollout speeds are employed. The model thus estimates which vaccination rates are too low to allow reaching herd immunity in 2021, depending on social interactions. Vaccination will considerably, but not immediately, help to curb the infection; thus limiting social interactions remains crucial for the months to come. [less ▲]

Detailed reference viewed: 217 (42 UL)
Full Text
See detailLa clause de non-concurrence des associés dans les SCOP : le coopérateur sur le bûcher du droit du travail
Hiez, David UL

in RTD Com: Revue Trimestrielle de Droit Commercial et Economique (2021), (3), 619-626

Detailed reference viewed: 104 (2 UL)
Full Text
Peer Reviewed
See detailElliptical Symmetry Tests in R
Ley, Christophe UL; Babić, Slad̄ana; Palangetić, Marko

in R Journal (2021), 13:2

The assumption of elliptical symmetry has an important role in many theoretical develop ments and applications. Hence, it is of primary importance to be able to test whether that assumption actually holds ... [more ▼]

The assumption of elliptical symmetry has an important role in many theoretical develop ments and applications. Hence, it is of primary importance to be able to test whether that assumption actually holds true or not. Various tests have been proposed in the literature for this problem. To the best of our knowledge, none of them has been implemented in R. This article describes the R package elliptical symmetry which implements several well-known tests for elliptical symmetry together with some recent tests. We demonstrate the testing procedures with a real data example. [less ▲]

Detailed reference viewed: 10 (0 UL)
Full Text
Peer Reviewed
See detailDie Wiedereinführung von EU-Binnengrenzkontrollen: ein unverhältnismäßiges, unwirksames und unzulässiges Mittel zur Bekämpfung der Pandemie
Gerkrath, Jörg UL

in Kritische Vierteljahresschrift für Gesetzgebung und Rechtswissenschaft (2021), 104(1), 75-87

Detailed reference viewed: 42 (6 UL)
Full Text
Peer Reviewed
See detailTalent development in natural science in elementary school: A juxtaposition of research and practice
Mack, Elena; Breit, Moritz; Krischler, Mireille UL et al

in Teaching and Teacher Education (2021), 104

We present a working theory of person-related predictors of talent development in natural science during elementary school. The working theory resulted from the juxtaposition of scientific findings and ... [more ▼]

We present a working theory of person-related predictors of talent development in natural science during elementary school. The working theory resulted from the juxtaposition of scientific findings and teachers' expertise. The results showed that both teachers and researchers conceive of talent development in natural science as a complex process including abilities, personality traits, and skills as predictors. However, teachers focused mainly on skills whereas the scientific literature emphasized cognitive abilities. The working theory can be used for the identification and promotion of natural science talent and the development of teachers' diagnostic skills to assess students’ potential in natural science. [less ▲]

Detailed reference viewed: 22 (0 UL)
Full Text
Peer Reviewed
See detailSecure Transmission in Massive MIMO System with Specular Component-based Beamforming and Artificial Noise over Ricean Fading Channel
Qu, Aiyan; Zhang, Xianyu; An, Kang et al

in IEEE Wireless Communications Letters (2021), 10(11, Nov. 2021),

This paper investigates the secure transmission in a multi-user massive MIMO system over Ricean fading channel in the presence of a multi-antenna eavesdropper. In order to reduce the system complexity and ... [more ▼]

This paper investigates the secure transmission in a multi-user massive MIMO system over Ricean fading channel in the presence of a multi-antenna eavesdropper. In order to reduce the system complexity and the channel estimation overhead, a low-complexity beamforming (BF) scheme using only the specular component is presented. Moreover, the generation of artificial noise (AN) is employed at the base station (BS) for additional security enhancement. Specifically, a tractable closedform lower bound for the achievable ergodic secrecy rate is derived. Furthermore, the optimal power allocation factor is obtained based on the asymptotic analysis to maximize the achievable ergodic secrecy rate. The analytical results reveal that the ergodic secrecy rate improves with the increase of Ricean K- factor and converges to a specific constant when increasing the number of antennas. The performance of the proposed scheme is evaluated through comprehensive simulations. [less ▲]

Detailed reference viewed: 21 (1 UL)
See detailTschechen in der deutschen Wehrmacht. Totgeschwiegene Schicksale
Janz, Nina UL

in CLIO-online (2021)

Detailed reference viewed: 38 (6 UL)
Full Text
See detailEuropean port cities in transition
Hesse, Markus UL

in Journal of Transport Geography (2021), 96

Detailed reference viewed: 55 (1 UL)
Full Text
Peer Reviewed
See detailChronic primary pain in the COVID-19 pandemic: how uncertainty and stress impact on functioning and suffering
Meulders, Ann; Vlaeyen, Johan W S; Evers, Andrea W M et al

in Pain (2021)

Detailed reference viewed: 23 (0 UL)
Full Text
Peer Reviewed
See detailRadio Resource Management Techniques for Multibeam Satellite Systems
Kisseleff, Steven UL; Lagunas, Eva UL; Abdu, Tedros Salih UL et al

in IEEE Communications Letters (2021), 25(8), 2448-2452

Next–generation of satellite communication (SatCom) networks are expected to support extremely high data rates for a seamless integration into future large satellite-terrestrial networks. In view of the ... [more ▼]

Next–generation of satellite communication (SatCom) networks are expected to support extremely high data rates for a seamless integration into future large satellite-terrestrial networks. In view of the coming spectral limitations, the main challenge is to reduce the cost (satellite launch and operation) per bit, which can be achieved by enhancing the spectral efficiencies. In addition, the capability to quickly and flexibly assign radio resources according to the traffic demand distribution has become a must for future multibeam broadband satellite systems. This article presents the radio resource management problems encountered in the design of future broadband SatComs and provides a comprehensive overview of the available techniques to address such challenges. Firstly, we focus on the demand matching formulation of the power and bandwidth assignment. Secondly, we present the scheduling design in practical multibeam satellite systems. Finally, a number of future challenges and the respective open research topics are described. [less ▲]

Detailed reference viewed: 241 (76 UL)
Full Text
Peer Reviewed
See detailLEO Satellite Constellations for 5G and Beyond: How Will They Reshape Vertical Domains?
Liu, Shicong; Gao, Zhen; Wu, Yongpeng et al

in IEEE Communications Magazine (2021), 59(7), 30-36

The rapid development of communication technologies in the past decades has provided immense vertical opportunities for individuals and enterprises. However, conventional terrestrial cellular networks ... [more ▼]

The rapid development of communication technologies in the past decades has provided immense vertical opportunities for individuals and enterprises. However, conventional terrestrial cellular networks have unfortunately neglected the huge geographical digital divide, s ince high-bandwidth wireless coverage is concentrated in urban areas. To meet the goal of “connecting the unconnected,” integrating low Earth orbit (LEO) satellites with the terrestrial cellular networks has been widely considered as a promising solution. In this article, we first introduce the development roadmap of LEO sa tellite constellations (SatCons), including early attempts in LEO satellites with the emerging LEO constellations. Further, we discuss the unique opportunities of employing LEO SatCons for the delivery of integrating 5G networks. Specifically, we present their key performance indicators, which offer important guidelines for the design of associated enabling techniques, and then discuss the potential impact of integrating LEO SatCons with typical 5G use cases, where we engrave our vision of various vertical domains reshaped by LEO SatCons. Technical challenges are finally provided to specify future research directions. [less ▲]

Detailed reference viewed: 36 (4 UL)
Full Text
Peer Reviewed
See detailRacial disparities in observers' attention to and estimations of others' pain
Kissi, Ama; van Ryckeghem, Dimitri UL; Mende-Siedlecki et al

in Pain (2021)

Research has demonstrated racial disparities in pain care such that Black patients often receive poorer pain care than White patients. Little is known about mechanisms accounting for the emergence of such ... [more ▼]

Research has demonstrated racial disparities in pain care such that Black patients often receive poorer pain care than White patients. Little is known about mechanisms accounting for the emergence of such disparities. The present study had 2 aims. First, we examined whether White observers' attentional processing of pain (using a visual search task [VST] indexing attentional engagement to and attentional disengagement from pain) and estimation of pain experience differed between White vs Black faces. Second, we examined whether these differences were moderated by (1) racially biased beliefs about pain experience and (2) the level of pain expressed by Black vs White faces. Participants consisted of 102 observers (87 females) who performed a VST assessing pain-related attention to White vs Black avatar pain faces. Participants also reported on racially biased beliefs about White vs Black individuals' pain experience and rated the pain intensities expressed by White and Black avatar faces. Results indicated facilitated attentional engagement towards Black (vs White) pain faces. Furthermore, observers who more strongly endorsed the belief that White individuals experience pain more easily than Black individuals had less difficulty disengaging from Black (vs White) pain faces. Regarding pain estimations, observers gave higher pain ratings to Black (vs White) faces expressing high pain and White (vs Black) faces expressing no pain. The current findings attest to the importance of future research into the role of observer attentional processing of sufferers' pain in understanding racial disparities in pain care. Theoretical and clinical implications are discussed, and future research directions are outlined. [less ▲]

Detailed reference viewed: 24 (0 UL)
Full Text
Peer Reviewed
See detailBlockPerf: A Hybrid Blockchain Emulator/Simulator Framework
Polge, Julien UL; Ghatpande, Sankalp UL; Kubler, Sylvain et al

in IEEE Access (2021), 9

Blockchain is increasingly used for registering, authenticating and validating digital assets (financial assets, real estate, etc.) and transactions, governing interactions, recording data and managing ... [more ▼]

Blockchain is increasingly used for registering, authenticating and validating digital assets (financial assets, real estate, etc.) and transactions, governing interactions, recording data and managing identification among multiple parties in a trusted, decentralized, and secure manner. Today, a large variety of blockchain technologies is expanding in order to fulfill technical and non-technical needs and requirements. Within this context, determining and most importantly evaluating the characteristics/performance of a given blockchain platform is crucial for system designers before deploying it. A number of blockchain simulators have been proposed in the literature over the past few years, as reviewed in this paper, but are often limited in several respects (lack of extensibility, do not allow for evaluating all aspects of a blockchain...). This paper extends and improves a state-of-the-art simulator (BlockSim) into a new simulator called ‘‘BlockPerf’’ to overcome those limitations. Both simulators are compared based on a real-life (benchmarking) Bitcoin scenario, whose results show that BlockPerf provides more realistic results than BlockSim, improving by around ≈50% (in average) the outcomes. [less ▲]

Detailed reference viewed: 63 (3 UL)
Full Text
Peer Reviewed
See detailWeighted numbers: Commentary on “The Number Sense Represents (Rational) Numbers” by Sam Clarke and Jacob Beck
Marinova, Mila UL; Fedele, Marta; Reynvoet, Bert

in Behavioral and Brain Sciences (2021)

Detailed reference viewed: 58 (4 UL)
Full Text
Peer Reviewed
See detailOn the Secrecy Capacity of MIMO Wiretap Channels: Convex Reformulation and Efficient Numerical Methods
Mukherjee, Anshu; Ottersten, Björn UL; Tran, Le-Nam

in IEEE Transactions on Communications (2021), 69(10), 6865-6878

This paper presents novel numerical approaches to finding the secrecy capacity of the multiple-input multiple-output (MIMO) wiretap channel subject to multiple linear transmit covariance constraints ... [more ▼]

This paper presents novel numerical approaches to finding the secrecy capacity of the multiple-input multiple-output (MIMO) wiretap channel subject to multiple linear transmit covariance constraints, including sum power constraint, per antenna power constraints and interference power constraint. An analytical solution to this problem is not known and existing numerical solutions suffer from slow convergence rate and/or high per-iteration complexity. Deriving computationally efficient solutions to the secrecy capacity problem is challenging since the secrecy rate is expressed as a difference of convex functions (DC) of the transmit covariance matrix, for which its convexity is only known for some special cases. In this paper we propose two low-complexity methods to compute the secrecy capacity along with a convex reformulation for degraded channels. In the first method we capitalize on the accelerated DC algorithm which requires solving a sequence of convex subproblems, for which we propose an efficient iterative algorithm where each iteration admits a closed-form solution. In the second method, we rely on the concave-convex equivalent reformulation of the secrecy capacity problem which allows us to derive the so-called partial best response algorithm to obtain an optimal solution. Notably, each iteration of the second method can also be done in closed form. The simulation results demonstrate a faster convergence rate of our methods compared to other known solutions. We carry out extensive numerical experiments to evaluate the impact of various parameters on the achieved secrecy capacity. [less ▲]

Detailed reference viewed: 26 (1 UL)
Full Text
Peer Reviewed
See detailAn Innovative Strategy Allowing a Holisitic System Change towards Circular Economy within Supply-Chains
Mangers, Jeff UL; Minoufekr, Meysam UL; Plapper, Peter UL et al

in Energies (2021), 14(14),

: The concept of the circular economy (CE) is receiving encouraging attention among scholars and practitioners, as a convenient solution to move away from the linear economy concept without neglecting the ... [more ▼]

: The concept of the circular economy (CE) is receiving encouraging attention among scholars and practitioners, as a convenient solution to move away from the linear economy concept without neglecting the goals of sustainable development. The main goals of the CE are the closing of resource loops and the keeping of resources in the system for as long as possible at the highest utility level. However, as a result of the lack of internationally accepted definitions of the CE and several unsolved barriers, an excessive and inconsistent number of different CE applications exist. Most fields are mainly focusing on making a linear system circular instead of applying the CE principles in a holistic way. This paper presents a strategy to close the mentioned inconsistency gap, by contrasting currently discussed CE barriers and goals and thereof deriving two areas with a need for action (1. identifying the needed collection, sorting, and recovery infrastructure, and 2. developing circular product design guidelines). The strategy itself consists of connecting these two areas through an improved information exchange between the end-of-life (EOL) and beginning-of-life (BOL) of products. The result is CE design guidelines which are in accordance with the available or needed collection, sorting, and recovery infrastructure. The proposed strategy presents an innovative solution to apply CE principles in a holistic manner, based on EOL-driven product design. [less ▲]

Detailed reference viewed: 97 (3 UL)
Full Text
Peer Reviewed
See detailExact thermal properties of free-fermionic spin chains
Białończyk, Michał; Gómez-Ruiz, Fernando Javier; Del Campo Echevarria, Adolfo UL

in SciPost Phys. (2021)

An exact description of integrable spin chains at finite temperature is provided using an elementary algebraic approach in the complete Hilbert space of the system. We focus on spin chain models that ... [more ▼]

An exact description of integrable spin chains at finite temperature is provided using an elementary algebraic approach in the complete Hilbert space of the system. We focus on spin chain models that admit a description in terms of free fermions, including paradigmatic examples such as the one-dimensional transverse-field quantum Ising and XY models. The exact partition function is derived and compared with the ubiquitous approximation in which only the positive parity sector of the energy spectrum is considered. Errors stemming from this approximation are identified in the neighborhood of the critical point at low temperatures. We further provide the full counting statistics of a wide class of observables at thermal equilibrium and characterize in detail the thermal distribution of the kink number and transverse magnetization in the transverse-field quantum Ising chain. [less ▲]

Detailed reference viewed: 40 (1 UL)
Full Text
Peer Reviewed
See detailHybrid Beamforming, User Scheduling, and Resource Allocation for Integrated Terrestrial-Satellite Communication
Peng, Deyi; Bandi, Ashok; Li, Yun et al

in IEEE Transactions on Vehicular Technology (2021), 70(9), 8868-8882

In this paper, we investigate hybrid beamforming, user scheduling, and resource allocation optimization based on spectrum coexisting forward transmission in integrated terrestrial-satellite network (ITSN ... [more ▼]

In this paper, we investigate hybrid beamforming, user scheduling, and resource allocation optimization based on spectrum coexisting forward transmission in integrated terrestrial-satellite network (ITSN) with the purpose of improving system sum rate and energy efficiency. Considering the limitation of on-board beamforming, a hybrid analog-digital beamforming scheme is designed under the scenario of millimeter wave (mmWave) coexisting in the ITSN framework. Besides, in order to further mitigate intra-beam and inter-beam interference, we propose an adaptive user scheduling scheme, which first determines the cluster center based on adaptive threshold, and then selects users with less channel correlation into a scheduling cluster. Moreover, we model system sum rate maximization problem that incorporates maximum power constrains and minimum data rate requirements. Combined with the aforementioned hybrid beamforming and user scheduling strategy, we formulate the sum rate maximizing problem to a pure power allocation issue. In view of the non-convexity and high complexity, we propose a feasible optimization method based on the minimum mean square error (MMSE) criterion and logarithmic linearization to optimize the power allocation for each user terminal (UT). Simulation results show that our proposed joint beamforming and resource allocation optimization scheduling scheme can achieve an attractive gain in system sum rate and energy efficiency compared with conservative beamforming and allocations. [less ▲]

Detailed reference viewed: 27 (4 UL)
Full Text
Peer Reviewed
See detailBayesian model uncertainty quantification for hyperelastic soft tissue models
Zeraatpisheh, Milad UL; Beex, Lars UL; Bordas, Stéphane UL

in Data-Centric Engineering (2021)

Patient-specific surgical simulations require the patient-specific identification of the constitutive parameters. The sparsity of the experimental data and the substantial noise in the data (e.g ... [more ▼]

Patient-specific surgical simulations require the patient-specific identification of the constitutive parameters. The sparsity of the experimental data and the substantial noise in the data (e.g., recovered during surgery) cause considerable uncertainty in the identification. In this exploratory work, parameter uncertainty for incompressible hyperelasticity, often used for soft tissues, is addressed by a probabilistic identification approach based on Bayesian inference. Our study particularly focuses on the uncertainty of the model: we investigate how the identified uncertainties of the constitutive parameters behave when different forms of model uncertainty are considered. The model uncertainty formulations range from uninformative ones to more accurate ones that incorporate more detailed extensions of incompressible hyperelasticity. The study shows that incorporating model uncertainty may improve the results, but this is not guaranteed. [less ▲]

Detailed reference viewed: 114 (25 UL)
Full Text
Peer Reviewed
See detailDigital twinning of Cellular Capsule Technology: emerging outcomes from the perspective of porous media mechanics
Urcun, Stéphane UL

in PLoS ONE (2021)

Spheroids encapsulated within alginate capsules are emerging as suitable in vitro tools to investigate the impact of mechanical forces on tumor growth since the internal tumor pressure can be retrieved ... [more ▼]

Spheroids encapsulated within alginate capsules are emerging as suitable in vitro tools to investigate the impact of mechanical forces on tumor growth since the internal tumor pressure can be retrieved from the deformation of the capsule. Here we focus on the particular case of Cellular Capsule Technology (CCT). We show in this contribution that a modeling approach accounting for the triphasic nature of the spheroid (extracellular matrix, tumor cells and interstitial fluid) offers a new perspective of analysis revealing that the pressure retrieved experimentally cannot be interpreted as a direct picture of the pressure sustained by the tumor cells and, as such, cannot therefore be used to quantify the critical pressure which induces stress-induced phenotype switch in tumor cells. The proposed multiphase reactive poro-mechanical model was cross-validated. Parameter sensitivity analyses on the digital twin revealed that the main parameters determining the encapsulated growth configuration are different from those driving growth in free condition, confirming that radically different phenomena are at play. Results reported in this contribution support the idea that multiphase reactive poro-mechanics is an exceptional theoretical framework to attain an in-depth understanding of CCT experiments, to confirm their hypotheses and to further improve their design. We show in this contribution that a modeling approach accounting for the triphasic nature of the spheroid (extracellular matrix, tumor cells and interstitial fluid) offers a new perspective of analysis revealing that the pressure retrieved experimentally cannot be interpreted as a direct picture of the pressure sustained by the tumor cells and, as such, cannot therefore be used to quantify the critical pressure which induces stress-induced phenotype switch in tumour cells. The proposed multiphase reactive poro-mechanical model was cross-validated. Parameter sensitivity analyses on the digital twin revealed that the main parameters determining the encapsulated growth configuration are different from those driving growth in free condition, confirming that radically different phenomena are at play.Results reported in this contribution support the idea that multiphase reactive poro-mechanics is an exceptional theoretical framework to attain an in-depth understanding of CCT experiments, to confirm their hypotheses and to further improve their design. [less ▲]

Detailed reference viewed: 143 (6 UL)
Full Text
Peer Reviewed
See detailSCR-Apriori for Mining ‘Sets of Contrasting Rules’
Aleksandrova, Marharyta UL; Chertov, Oleg

in Studies in Fuzziness and Soft Computing (2021), 393

Detailed reference viewed: 31 (2 UL)
Full Text
Peer Reviewed
See detailMachine Learning Force Fields: Recent Advances and Remaining Challenges
Poltavskyi, Igor UL; Tkatchenko, Alexandre UL

in Journal of Physical Chemistry Letters (2021)

Detailed reference viewed: 39 (1 UL)
Full Text
Peer Reviewed
See detailFAIR chemical structures in the Journal of Cheminformatics
Schymanski, Emma UL; Bolton, Evan E.

in Journal of Cheminformatics (2021), 13(1), 50

Abstract The ability to access chemical information openly is an essential part of many scientific disciplines. The Journal of Cheminformatics is leading the way for rigorous, open cheminformatics in many ... [more ▼]

Abstract The ability to access chemical information openly is an essential part of many scientific disciplines. The Journal of Cheminformatics is leading the way for rigorous, open cheminformatics in many ways, but there remains room for improvement in primary areas. This letter discusses how both authors and the journal alike can help increase the FAIR ness (Findability, Accessibility, Interoperability, Reusability) of the chemical structural information in the journal. A proposed chemical structure template can serve as an interoperable Additional File format (already accessible ), made more findable by linking the DOI of this data file to the article DOI metadata, supporting further reuse . [less ▲]

Detailed reference viewed: 70 (0 UL)
Full Text
Peer Reviewed
See detailFrom Hume to Wuhan: An Epistemological Journey on the Problem of Induction in COVID-19 Machine Learning Models and its Impact Upon Medical Research
Vega Moreno, Carlos Gonzalo UL

in IEEE Access (2021), 9

Advances in computer science have transformed the way artificial intelligence is employed in academia, with Machine Learning (ML) methods easily available to researchers from diverse areas thanks to ... [more ▼]

Advances in computer science have transformed the way artificial intelligence is employed in academia, with Machine Learning (ML) methods easily available to researchers from diverse areas thanks to intuitive frameworks that yield extraordinary results. Notwithstanding, current trends in the mainstream ML community tend to emphasise <italic>wins</italic> over knowledge, putting the scientific method aside, and focusing on maximising metrics of interest. Methodological flaws lead to poor justification of method choice, which in turn leads to disregard the limitations of the methods employed, ultimately putting at risk the translation of solutions into real-world clinical settings. This work exemplifies the impact of the problem of induction in medical research, studying the methodological issues of recent solutions for computer-aided diagnosis of COVID-19 from chest X-Ray images. [less ▲]

Detailed reference viewed: 99 (3 UL)
Full Text
Peer Reviewed
See detailCan Offline Testing of Deep Neural Networks Replace Their Online Testing?
Ul Haq, Fitash UL; Shin, Donghwan UL; Nejati, Shiva UL et al

in Empirical Software Engineering (2021), 26(5),

We distinguish two general modes of testing for Deep Neural Networks (DNNs): Offline testing where DNNs are tested as individual units based on test datasets obtained without involving the DNNs under test ... [more ▼]

We distinguish two general modes of testing for Deep Neural Networks (DNNs): Offline testing where DNNs are tested as individual units based on test datasets obtained without involving the DNNs under test, and online testing where DNNs are embedded into a specific application environment and tested in a closed-loop mode in interaction with the application environment. Typically, DNNs are subjected to both types of testing during their development life cycle where offline testing is applied immediately after DNN training and online testing follows after offline testing and once a DNN is deployed within a specific application environment. In this paper, we study the relationship between offline and online testing. Our goal is to determine how offline testing and online testing differ or complement one another and if offline testing results can be used to help reduce the cost of online testing? Though these questions are generally relevant to all autonomous systems, we study them in the context of automated driving systems where, as study subjects, we use DNNs automating end-to-end controls of steering functions of self-driving vehicles. Our results show that offline testing is less effective than online testing as many safety violations identified by online testing could not be identified by offline testing, while large prediction errors generated by offline testing always led to severe safety violations detectable by online testing. Further, we cannot exploit offline testing results to reduce the cost of online testing in practice since we are not able to identify specific situations where offline testing could be as accurate as online testing in identifying safety requirement violations. [less ▲]

Detailed reference viewed: 116 (28 UL)
Full Text
Peer Reviewed
See detailTopological Defect-Guided Regular Stacking of Focal Conic Domains in Hybrid-Aligned Smectic Liquid Crystal Shells
Noh, Junghyun; Lagerwall, Jan UL

in Crystals (2021), 11(8), 913

We study liquid crystal (LC) shells in hybrid configuration (director tangential to the inside but normal to the outside) as they slowly undergo a transition from a nematic (N) to a smectic-A (SmA) phase ... [more ▼]

We study liquid crystal (LC) shells in hybrid configuration (director tangential to the inside but normal to the outside) as they slowly undergo a transition from a nematic (N) to a smectic-A (SmA) phase. Every shell has two antipodal +1 topological defects, at the thinnest and thickest points, respectively. On cooling from N to SmA, the symmetry axis connecting the defects gradually reorients from blackalong gravity to perpendicular to it, reversibly and continuously, if the LC and aqueous phase are density matched at the N-SmA transition. This suggests reduced density near the defects---reflecting a local reduction in order---under the strong confinement with antagonistic boundary conditions. In the SmA phase, a regular array of focal conic domains (FCDs) develops, templated in position and orientation by the +1 defect at the thinnest point. Around this defect, a single complete toroidal FCD always develops, surrounded by incomplete FCDs. In contrast to similar FCD arrangements on flat aqueous interfaces, this is a stable situation, since the two +1 defects are required by the spherical topology. Our results demonstrate how the topological defects of LC shells can be used to template complex self-organized structures. blackWith a suitable adaption of the LC chemistry, shells might serve as a basis for producing solid particles with complex yet highly regular morphologies. [less ▲]

Detailed reference viewed: 34 (0 UL)
Full Text
Peer Reviewed
See detailNationwide implementation of media literacy training sessions on internet safety
Tiemann, Aline; Melzer, André UL; Steffgen, Georges UL

in Communications: the European Journal of Communication Research (2021)

Although numerous media literacy training sessions on internet safety for children and adolescents have been conducted, their number contrasts sharply with the few systematic studies on their ... [more ▼]

Although numerous media literacy training sessions on internet safety for children and adolescents have been conducted, their number contrasts sharply with the few systematic studies on their effectiveness. In this study, we describe the evaluation of nationwide-implemented training sessions on internet safety in Luxembourg, which included perceptions of learning outcomes and evaluations of implementation and effectiveness. Training data from 2011 to 2018 were analyzed, including 28,060 students and 5,031 teachers. Students reported pronounced learning effects, especially for younger students and for repeated training participation. Teachers greatly appreciated the implementation and effectiveness, which generally increased over the years. The perceived effectiveness of the training was significantly related to teachers’ planning to cover internet safety topics in future lessons. The present study shows that carefully planned and continuously evaluated training sessions on internet safety successfully support children’s understanding and teachers’ willingness to implement internet safety in their curriculum. [less ▲]

Detailed reference viewed: 121 (0 UL)
Full Text
Peer Reviewed
See detailLes archives du Web luxembourgeois. Histoire, enjeux et perspectives
Els, Ben; Maurer, Yves; Schafer, Valerie UL

in Hemecht: Zeitschrift für Luxemburger Geschichte (2021), 73

Cet article entend contribuer à faire découvrir l’archivage du Web luxembourgeois, son histoire, sa continuité par rapport à d’autres initiatives européennes, ses atouts et ses spécificités, avant de ... [more ▼]

Cet article entend contribuer à faire découvrir l’archivage du Web luxembourgeois, son histoire, sa continuité par rapport à d’autres initiatives européennes, ses atouts et ses spécificités, avant de proposer des réflexions sur les usages scientifiques qui peuvent en âtre faits, et ce au-delà de la seule histoire du numérique. [less ▲]

Detailed reference viewed: 83 (7 UL)
Full Text
Peer Reviewed
See detailThe impact of Kelvin probe force microscopy operation modes and environment on grain boundary band bending in perovskite and Cu(In,Ga)Se2 solar cells
Martin Lanzoni, Evandro UL; Gallet, Thibaut UL; Spindler, Conrad UL et al

in Nano Energy (2021), 88

An in-depth understanding of the electronic properties of grain boundaries (GBs) in polycrystalline semiconductor absorbers is of high importance since their charge carrier recombination rates may be very ... [more ▼]

An in-depth understanding of the electronic properties of grain boundaries (GBs) in polycrystalline semiconductor absorbers is of high importance since their charge carrier recombination rates may be very high and hence limit the solar cell device performance. Kelvin Probe Force Microscopy (KPFM) is the method of choice to investigate GB band bending on the nanometer scale and thereby helps to develop passivation strategies. Here, it is shown that the workfunction, measured with amplitude modulation (AM)-KPFM, which is by far the most common KPFM measurement mode, is prone to exhibit measurement artifacts at grain boundaries on typical solar cell absorbers such as Cu(In,Ga)Se2 and CH3NH3PbI3. This is a direct consequence of a change in the cantilever–sample distance that varies on rough samples. Furthermore, we critically discuss the impact of different environments (air versus vacuum) and show that air exposure alters the GB and facet contrast, which leads to erroneous interpretations of the GB physics. Frequency modulation (FM)-KPFM measurements on non-air-exposed CIGSe and perovskite absorbers show that the amount of band bending measured at the GB is negligible and that the electronic landscape of the semiconductor surface is dominated by facet-related contrast due to the polycrystalline nature of the absorbers. [less ▲]

Detailed reference viewed: 118 (13 UL)
Full Text
Peer Reviewed
See detailFeasibility of ERA5 integrated water vapor trends for climate change analysis in continental Europe: An evaluation with GPS (1994–2019) by considering statistical significance
Yuan, Peng; Hunegnaw, Addisu UL; Alshawaf, Fadwa et al

in Remote Sensing of Environment (2021), 260(112416),

Although the statistical significances for the trends of integrated water vapor (IWV) are essential for a correct interpretation of climate change signals, obtaining accurate IWV trend estimates with ... [more ▼]

Although the statistical significances for the trends of integrated water vapor (IWV) are essential for a correct interpretation of climate change signals, obtaining accurate IWV trend estimates with realistic uncertainties remains a challenge. This study evaluates the feasibility of the IWV trends derived from the newly released fifth generation European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric reanalysis (ERA5) for climate change analysis in continental Europe. This is achieved by comparing the trends derived from in-situ ground-based Global Positioning System (GPS)’s daily IWV series from 1994 to 2019 at 109 stations. The realistic uncertainties and statistical significances of the IWV trends are evaluated with the time series analysis on their noise characteristics and proper noise models. Results show that autoregressive moving average ARMA(1,1) noise model is preferred rather than the commonly assumed white noise (WN) or first-order autoregressive AR(1) noise for about 68% of the ERA5 and GPS IWV series. An improper noise model would misevaluate the trend uncertainty of an IWV time series, compared with its specific preferred noise model. For example, ARMA(1,1) may misevaluate the standard deviations of their trend estimates (0.1–0.3 kg m−2 decade−1) by 10%. Nevertheless, ARMA(1,1) is recommended as the default noise model for the ERA5 and GPS IWV series. However, the preferred noise model for each ERA5 minus GPS (E-G) IWV series should be specifically determined, because the AR(1)-related models can result in an underestimation on its trend uncertainty by 90%. In contrast, power-law (PL) model can lead to an overestimation by up to nine times. The E-G IWV trends are within −0.2–0.4 kg m−2 decade−1, indicating that the ERA5 is a potential data source of IWV trends for climate change analysis in continental Europe. The ERA5 and GPS IWV trends are consistent in their magnitudes and geographical patterns, lower in Northwest Europe (0–0.4 kg m−2 decade−1) but higher around the Mediterranean Sea (0.6–1.4 kg m−2 decade−1). [less ▲]

Detailed reference viewed: 61 (3 UL)
Full Text
Peer Reviewed
See detailA hyper-reduction method using adaptivity to cut the assembly costs of reduced order models
Hale, Jack UL; Schenone, Elisa; Baroli, Davide UL et al

in Computer Methods in Applied Mechanics and Engineering (2021), 380

At every iteration or timestep of the online phase of some reduced-order modelling schemes, large linear systems must be assembled and then projected onto a reduced order basis of small dimension. The ... [more ▼]

At every iteration or timestep of the online phase of some reduced-order modelling schemes, large linear systems must be assembled and then projected onto a reduced order basis of small dimension. The projected small linear systems are cheap to solve, but assembly and projection are now the dominant computational cost. In this paper we introduce a new hyper-reduction strategy called reduced assembly (RA) that drastically cuts these costs. RA consists of a triangulation adaptation algorithm that uses a local error indicator to con- struct a reduced assembly triangulation specially suited to the reduced order basis. Crucially, this reduced assembly triangulation has fewer cells than the original one, resulting in lower assembly and projection costs. We demonstrate the efficacy of RA on a Galerkin-POD type reduced order model (RAPOD). We show performance increases of up to five times over the baseline Galerkin-POD method on a non-linear reaction-diffusion problem solved with a semi-implicit time-stepping scheme and up to seven times for a 3D hyperelasticity problem solved with a continuation Newton-Raphson algorithm. The examples are implemented in the DOLFIN finite element solver using PETSc and SLEPc for linear algebra. Full code and data files to produce the results in this paper are provided as supplementary material. [less ▲]

Detailed reference viewed: 392 (52 UL)
Full Text
Peer Reviewed
See detailRandom access procedure over non-terrestrial networks: From theory to practice
Kodheli, Oltjon UL; Abdalla, Abdelrahman UL; Querol, Jorge UL et al

in IEEE Access (2021)

Non-terrestrial Networks (NTNs) have become an appealing concept over the last few years and they are foreseen as a cornerstone for the next generations of mobile communication systems. Despite opening up ... [more ▼]

Non-terrestrial Networks (NTNs) have become an appealing concept over the last few years and they are foreseen as a cornerstone for the next generations of mobile communication systems. Despite opening up new market opportunities and use cases for the future, the novel impairments caused by the signal propagation over the NTN channel, compromises several procedures of the current cellular standards. One of the first and most important procedures impacted is the random access (RA) procedure, which is mainly utilized for achieving uplink synchronization among users in several standards, such as the fourth and fifth generation of mobile communication (4 & 5G) and narrowband internet of things (NB-IoT). In this work, we analyse the challenges imposed by the considerably increased delay in the communication link on the RA procedure and propose new solutions to overcome those challenges. A trade-off analysis of various solutions is provided taking into account also the already existing ones in the literature. In order to broaden the scope of applicability, we keep the analysis general targeting 4G, 5G and NB-IoT systems since the RA procedure is quasi-identical among these technologies. Last but not least, we go one step further and validate our techniques in an experimental setup, consisting of a user and a base station implemented in open air interface (OAI), and an NTN channel implemented in hardware that emulates the signal propagation delay. The laboratory test-bed built in this work, not only enables us to validate various solutions, but also plays a crucial role in identifying novel challenges not previously treated in the literature. Finally, an important key performance indicator (KPI) of the RA procedure over NTN is shown, which is the time that a single user requires to establish a connection with the base station. [less ▲]

Detailed reference viewed: 56 (6 UL)
Full Text
Peer Reviewed
See detailNB-IoT via LEO satellites: An efficient resource allocation strategy for uplink data transmission
Kodheli, Oltjon UL; Maturo, Nicola; Chatzinotas, Symeon UL et al

in IEEE Internet of Things Journal (2021)

Detailed reference viewed: 36 (2 UL)
Full Text
Peer Reviewed
See detailThe missing risk premium in exchange rates
Penasse, Julien UL; Magnus, Dahlquist

in Journal of Financial Economics (2021)

Detailed reference viewed: 20 (1 UL)
See detailHöchste Kolonialzeit. Sonderweg Saarland
Bloch, Natalie UL

in Theater heute (2021), (7), 61-62

Detailed reference viewed: 44 (1 UL)
Full Text
See detailThe Handbook of Diverse Economies
Schulz, Christian UL

in Economic Geography (2021)

Detailed reference viewed: 56 (0 UL)
Full Text
Peer Reviewed
See detailOn the Impact of Sample Duplication in Machine Learning based Android Malware Detection
Zhao, Yanjie; Li, Li; Wang, Haoyu et al

in ACM Transactions on Software Engineering and Methodology (2021), 30(3), 1-38

Detailed reference viewed: 31 (0 UL)
Full Text
Peer Reviewed
See detailSurface anchoring mediates bifurcation in nematic microflows within cylindrical capillaries
Paul, Steffen; Eric, Stellamanns; Sengupta, Anupam UL

in Physics of Fluids (2021), 33(072005), 072005-1-072005-13

Capillary microflows of liquid crystal phases are central to material, biological and bio-inspired systems. Despite their fundamental and applied significance, a detailed understanding of the stationary ... [more ▼]

Capillary microflows of liquid crystal phases are central to material, biological and bio-inspired systems. Despite their fundamental and applied significance, a detailed understanding of the stationary behavior of nematic liquid crystals (NLC-s) in cylindrical capillaries is still lacking. Here, using numerical simulations based on the continuum theory of Leslie, Ericksen, and Parodi, we investigate stationary NLC flows within cylindrical capillaries possessing homeotropic (normal) and uniform planar anchoring conditions. By considering the material parameters of the flow-aligning NLC, 5CB, we report that instead of the expected, unique director field monotonically approaching the alignment angle over corresponding Ericksen numbers (dimensionless number capturing viscous vs elastic effects), a second solution emerges at a threshold flow rate (or applied pressure gradient). We demonstrate that the onset of the second solution, a nematodynamic bifurcation yielding distinct director configurations at the threshold pressure gradient, can be controlled by the surface anchoring and the flow driving mechanism (pressure-driven or volume-driven). For homeotropic surface anchoring, this alternate director field orients against the alignment angle in the vicinity of the capillary center; while in the uniform planar case, the alternate director field extends throughout the capillary volume, leading to reduction of the flow speed with increasing pressure gradients. While the practical realization and utilization of such nematodynamic bifurcations still await systematic exploration, signatures of the emergent rheology have been reported by the authors previously within microfluidic environments, under both homeotropic and planar anchoring conditions. [less ▲]

Detailed reference viewed: 25 (2 UL)
Full Text
Peer Reviewed
See detailDigitized-counterdiabatic quantum approximate optimization algorithm
Chandarana, P.; Hegade, N. N.; Paul, K. et al

in Physical Review Research (2021)

The quantum approximate optimization algorithm (QAOA) has proved to be an e ective classical-quantum algorithm serving multiple purposes, from solving combinatorial optimization problems to finding the ... [more ▼]

The quantum approximate optimization algorithm (QAOA) has proved to be an e ective classical-quantum algorithm serving multiple purposes, from solving combinatorial optimization problems to finding the ground state of many-body quantum systems. Since QAOA is an ansatz-dependent algorithm, there is always a need to design ansatz for better optimization. To this end, we propose a digitized version of QAOA enhanced via the use of shortcuts to adiabaticity. Specifically, we use a counterdiabatic (CD) driving term to design a better ansatz, along with the Hamiltonian and mixing terms, enhancing the global performance. We apply our digitizedcounterdiabatic QAOA to Ising models, classical optimization problems, and the P-spin model, demonstrating that it outperforms standard QAOA in all cases we study. [less ▲]

Detailed reference viewed: 22 (1 UL)