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See detailDemand-Based Adaptive Multi-Beam Pattern and Footprint Planning for High Throughput GEO Satellite Systems
Jubba Honnaiah, Puneeth UL; Maturo, Nicola; Chatzinotas, Symeon UL et al

in IEEE Open Journal of the Communications Society (2021)

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See detailScalable Cell-Free Massive MIMO Systems: Impact of Hardware Impairments
Papazafeiropoulos, Anastasios; Björnson, Emil; Kourtessis, Pandelis et al

in IEEE Transactions on Vehicular Technology (2021), 70(10), 9701-9715

Scalable cell-free CF (SCF) massive multiple-input-multiple-output (mMIMO) systems is a promising technology to cover the demands for higher data rates and increasing number of users in fifth generation ... [more ▼]

Scalable cell-free CF (SCF) massive multiple-input-multiple-output (mMIMO) systems is a promising technology to cover the demands for higher data rates and increasing number of users in fifth generation (5G) networks and beyond. According to this concept, a large number of distributed access points (APs) communicates with the users in the network by means of joint coherent transmission while facing the main challenges against standard CF mMIMO systems being their high fronthaul load and computational complexity. Given that the cost-efficient deployment of such large networks requires low-cost transceivers being prone to unavoidable hardware imperfections, in this work, we focus on their impact on the advantageous SCF mMIMO systems by means of a general model accounting for both additive and multiplicative hardware impairments (HWIs). Notably, the scalability, depending on the time-variant characteristics of the network, is clearly affected by means of HWIs being time-varying. There is no other work in the literature studying the phase noise (PN) in CF mMIMO systems or in general any HWIs in SCF mMIMO systems. Hence, we derive upper and lower bounds on the uplink capacity accounting for HWIs. Especially, the lower bound is derived in closed-form by means of the theory of deterministic equivalents (DEs) and after obtaining the optimal hardware-aware (HA) partial minimum mean-squared error (PMMSE) combiner. Among the interesting findings, we observe that separate local oscillators (SLOs) outperform a common LO (CLO) architecture, and the additive transmit distortion degrades more the performance than the receive distortion. [less ▲]

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See detailVortical flow structures induced by red blood cells in capillaries.
Yaya, François; Römer, Johannes; Guckenberger, Achim et al

in Microcirculation (New York, N.Y. : 1994) (2021), 28(5), 12693

OBJECTIVE: Knowledge about the flow field of the plasma around the red blood cells in capillary flow is important for a physical understanding of blood flow and the transport of micro- and nanoparticles ... [more ▼]

OBJECTIVE: Knowledge about the flow field of the plasma around the red blood cells in capillary flow is important for a physical understanding of blood flow and the transport of micro- and nanoparticles and molecules in the flowing plasma. We conducted an experimental study on the flow field around red blood cells in capillary flow that is complemented by simulations of vortical flow between red blood cells. METHODS: Red blood cells were injected in a 10 × 12 µm rectangular microchannel at a low hematocrit, and the flow field around one or two cells was captured by a high-speed camera that tracked 250 nm nanoparticles in the flow field, acting as tracers. RESULTS: While the flow field around a steady "croissant" shape is found to be similar to that of a rigid sphere, the flow field around a "slipper" shape exhibits a small vortex at the rear of the red blood cell. Even more pronounced are vortex-like structures observed in the central region between two neighboring croissants. CONCLUSIONS: The rotation frequency of the vortices is to a good approximation, inversely proportional to the distance between the cells. Our experimental data are complemented by numerical simulations. [less ▲]

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See detailHeartbeat evoked potentials in patients with posttraumatic stress disorder: an unaltered neurobiological regulation system?
Schmitz, Marius; Müller, Laura E.; Seitz, Katja I. et al

in European Journal of Psychotraumatology (2021), 12(1), 1987686

Background: Early life maltreatment is a risk factor for psychiatric disorders, including posttraumatic stress disorder (PTSD). Posttraumatic stress disorder is a severe and heterogeneous disorder with ... [more ▼]

Background: Early life maltreatment is a risk factor for psychiatric disorders, including posttraumatic stress disorder (PTSD). Posttraumatic stress disorder is a severe and heterogeneous disorder with fluctuating states of emotional over- and undermodulation including hypervigilance, dissociation, and emotion regulation deficits. The perception and regulation of emotions have been linked to interoception, the cortical representation and sensing of inner bodily processes. Although first therapeutic approaches targeting bodily sensations have been found effective in patients with PTSD, and deficits in interoceptive signal representation have been reported in other trauma-related disorders such as borderline personality disorder (BPD), the role of interoception remains largely unexplored for PTSD. Objective: The objective was to investigate the cortical representation of cardiac interoceptive signals in patients with PTSD and its associations with early life maltreatment, trait dissociation, and emotion dysregulation. Methods: Twenty-four medication-free patients with PTSD and 31 healthy controls (HC) completed a 5-min resting electrocardiogram (ECG) with parallel electroencephalogram (EEG). Heartbeat evoked potential (HEP) amplitudes as a measure for cortical representation of cardiac interoceptive signals were compared between groups and correlated with self-report questionnaires. Results: We did not find significantly different mean HEP amplitudes in patients with PTSD compared to HC, although HEPs of patients with PTSD were descriptively higher. No significant associations between mean HEP amplitudes and early life maltreatment, trait dissociation or emotion dysregulation were obtained within the groups. Conclusion: The current finding does not indicate deficits in interoceptive signal representation at rest in individuals with PTSD. Whether patients with PTSD show altered HEP modulations during emotion regulation tasks and might benefit from therapeutic approaches aiming at changing the perception of bodily signals, needs to be investigated in future studies. [less ▲]

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See detailLe Congrès de Vienne et le statut international du Grand-Duché de Luxembourg : théories et réalités du droit des gens de l’Europe
Erpelding, Michel UL

in Actes de la section des sciences morales et politiques de l'Institut grand-ducal (2021), 24

This articles examines the international status of Luxembourg between 1815 and 1867 from the perspective of the international law applicable at that time and based on the relevant state practice. It ... [more ▼]

This articles examines the international status of Luxembourg between 1815 and 1867 from the perspective of the international law applicable at that time and based on the relevant state practice. It contends that - from the perspective of international law - Luxembourg emerged as a state after the evacuation of Belgian troops from its territory in 1839. [less ▲]

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See detailOptimal Randomized Partial Checking for Decryption Mix Nets
Haines, Thomas; Mueller, Johannes UL

in Information Security and Privacy - 26th Australasian Conference, ACISP 2021, Virtual Event, December 1-3, 2021, Proceedings (2021)

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See detailWhere were the repair ingredients for Defects4j bugs?
Yang, Deheng; Liu, Kui; Kim, Dongsun et al

in Empirical Software Engineering (2021), 26(6), 1--33

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See detailUsing Blockchain to Coordinate Federal Processes: The Case of Germany's Federal Office for Migration and Refugees
Amend, Julia; van Dun, Christopher; Fridgen, Gilbert UL et al

in Urbach, Nils; Röglinger, Maximilian; Kautz, Karlheinz (Eds.) et al Digitalization Cases Vol. 2: Mastering Digital Transformation for Global Business (2021)

(a)Situation faced: The German asylum procedure requires close cooperation and information exchange between various authorities at the municipal, state, and federal levels. Federal separation of ... [more ▼]

(a)Situation faced: The German asylum procedure requires close cooperation and information exchange between various authorities at the municipal, state, and federal levels. Federal separation of competencies inhibits the delegation of process governance to a central authority such as the Federal Office for Migration and Refugees (BAMF). This separation also leads to regional differences as federal laws govern the procedure's general steps, whereas state laws govern implementation. Moreover, existing solutions for cross-organizational collaboration are limited in terms of flexibility, security, and data quality. As a result, the exchange of certain data on asylum procedures still occurs using Excel spreadsheets and e-mails.(b)Action taken: Against this backdrop, the BAMF explored technological options that would support the decentralized governance of the asylum procedure. After a preliminary evaluation, the BAMF decided to explore a solution based on blockchain technology. Building upon a successful proof of concept, the BAMF initiated a pilot project with Saxony's central immigration authority. This project aims to develop a blockchain solution that supports the coordination of asylum procedures and can be easily adapted to local differences and functional requirements.(c)Results achieved: The use of the blockchain solution allows for efficient, secure, and timely distribution of status information. It supports communication and improves coordination between authorities. Despite an apparent conflict between blockchain principles and data privacy requirements, the BAMF's design complies with relevant regulation (notably the GDPR). As a first-of-its-kind project, it outlines best practices and provides valuable insights into opportunities and challenges arising from the use of blockchain in the public sector.(d)Lessons learned: The BAMF's case demonstrates that blockchain solutions can be promising alternatives when the delegation of process governance to a central party is not desirable and when federal principles of organization are to be reflected technologically. However, blockchain projects require special attention to managing know-how and capabilities, software development activities, stakeholders, the regulatory context, and cross-organizational governance. [less ▲]

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See detailThe Proposal for a Directive on Adequate Minimum Wages in the EU
Ratti, Luca UL

in EU Law Live - Weekend Edition (2021)

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See detailIn-Work poverty in the EU - EU Law Live Special Issue (I)
Ratti, Luca UL; Garcia Munoz Alhambra, Manuel Antonio UL

in EU Law Live - Weekend Edition (2021)

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See detailContrast adaptation in face perception revealed through EEG and behavior
Gwinn, O. Scott; Retter, Talia UL; O'Neil, S. F. et al

in Frontiers in Systems Neuroscience (2021)

Exposure to a face can produce biases in the perception of subsequent faces. Typically, these face aftereffects are studied by adapting to an individual face or category (e.g., faces of a given gender ... [more ▼]

Exposure to a face can produce biases in the perception of subsequent faces. Typically, these face aftereffects are studied by adapting to an individual face or category (e.g., faces of a given gender) and can result in renormalization of perceptions such that the adapting face appears more neutral. These shifts are analogous to chromatic adaptation, where a renormalization for the average adapting color occurs. However, in color vision, adaptation can also adjust to the variance or range of colors in the distribution. We examined whether this variance or contrast adaptation also occurs for faces, using an objective EEG measure to assess response changes following adaptation. An average female face was contracted or expanded along the horizontal or vertical axis to form four images. Observers viewed a 20 s sequence of the four images presented in a fixed order at a rate of 6 Hz, while responses to the faces were recorded with EEG. A 6 Hz signal was observed over right occipito-temporal channels, indicating symmetric responses to the four images. This test sequence was repeated after 20 s adaptation to alternations between two of the faces (e.g., horizontal contracted and expanded). This adaptation resulted in an additional signal at 3 Hz, consistent with asymmetric responses to adapted and non-adapted test faces. Adapting pairs have the same mean (undistorted) as the test sequence and thus should not bias responses driven only by the mean. Instead, the results are consistent with selective adaptation to the distortion axis. A 3 Hz signal was also observed after adapting to face pairs selected to induce a mean bias (e.g., expanded vertical and expanded horizontal), and this signal was not significantly different from that observed following adaption to a single image that did not form part of the test sequence (e.g., a single image expanded both vertically and horizontally). In a further experiment, we found that this variance adaptation can also be observed behaviorally. Our results suggest that adaptation calibrates face perception not only for the average characteristics of the faces we experience but also for the gamut of faces to which we are exposed. [less ▲]

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See detailA Novel Proof of Shuffle: Exponentially Secure Cut-and-Choose
Haines, Thomas; Mueller, Johannes UL

in Information Security and Privacy - 26th Australasian Conference, ACISP 2021, Virtual Event, December 1-3, 2021, Proceedings (2021)

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See detailRare Anemias: Are Their Names Just Smoke and Mirrors?
Simionato, Greta; van Wijk, Richard; Quint, Stephan et al

in Frontiers in physiology (2021), 12

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See detailStabilizing variable selection and regression
Pfister, Niklas; Williams, Evan UL; Peters, Jonas et al

in Annals of Applied Statistics (2021), 15(3),

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See detailPamphlet". Le qualificatif de la discorde
Saintes, Laetitia UL

in Legoy, Corinne; Déruelle, Aude (Eds.) Les Mots du politique (1815-1848) (2021)

Parmi les termes marquants de la langue politique, celui de « pamphlet » est particulièrement exemplaire de l’énergie polémique du XIXe siècle. Comme le genre qu’il désigne, le terme est avant tout ... [more ▼]

Parmi les termes marquants de la langue politique, celui de « pamphlet » est particulièrement exemplaire de l’énergie polémique du XIXe siècle. Comme le genre qu’il désigne, le terme est avant tout polémique : l’assimilation d’un écrit à un pamphlet, péjorative ou non, n’en est pas moins révélatrice des tensions à l’oeuvre dans le lexique politique de la Restauration. Comment celle-ci entend-elle le terme de « pamphlet » ? Comment s’illustre-t-il dans les champs politique et littéraire ? C’est ce que nous tenterons de déterminer à l’aide des écrits pamphlétaires de Paul-Louis Courier. [less ▲]

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See detailMultiomic profiling of the liver across diets and age in a diverse mouse population
Williams, Evan UL; Pfister, Niklas; Roy, Suheeta et al

in Cell Systems (2021)

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See detailRed blood cell phenotyping from 3D confocal images using artificial neural networks.
Simionato, Greta; Hinkelmann, Konrad; Chachanidze, Revaz et al

in PLoS computational biology (2021), 17(5), 1008934

The investigation of cell shapes mostly relies on the manual classification of 2D images, causing a subjective and time consuming evaluation based on a portion of the cell surface. We present a dual-stage ... [more ▼]

The investigation of cell shapes mostly relies on the manual classification of 2D images, causing a subjective and time consuming evaluation based on a portion of the cell surface. We present a dual-stage neural network architecture for analyzing fine shape details from confocal microscopy recordings in 3D. The system, tested on red blood cells, uses training data from both healthy donors and patients with a congenital blood disease, namely hereditary spherocytosis. Characteristic shape features are revealed from the spherical harmonics spectrum of each cell and are automatically processed to create a reproducible and unbiased shape recognition and classification. The results show the relation between the particular genetic mutation causing the disease and the shape profile. With the obtained 3D phenotypes, we suggest our method for diagnostics and theragnostics of blood diseases. Besides the application employed in this study, our algorithms can be easily adapted for the 3D shape phenotyping of other cell types and extend their use to other applications, such as industrial automated 3D quality control. [less ▲]

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See detailA Declaration of Software Independence
Jamroga, Wojciech UL; Ryan, Peter Y A UL; Schneider, Steve et al

in Protocols, Strands, and Logic - Essays Dedicated to Joshua Guttman on the Occasion of his 66.66th Birthday (2021)

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See detailCrossover between distinct symmetries in solid solutions of rare earth nickelates
Fowlie, Jennifer; Mundet, Bernat; Toulouse, Constance UL et al

in APL MATERIALS (2021), 9(8),

A strong coupling of the lattice to functional properties is observed in many transition metal oxide systems, such as the ABO(3) perovskites. In the quest for tailor-made materials, it is essential to be ... [more ▼]

A strong coupling of the lattice to functional properties is observed in many transition metal oxide systems, such as the ABO(3) perovskites. In the quest for tailor-made materials, it is essential to be able to control the structural properties of the compound(s) of interest. Here thin film solid solutions that combine NdNiO3 and LaNiO3, two materials with the perovskite structure but distinct space groups, are analyzed. Raman spectroscopy and scanning transmission electron microscopy are combined in a synergistic approach to fully determine the mechanism of the structural crossover with chemical composition. It is found that the symmetry transition is achieved by phase coexistence in a way that depends on the substrate selected. These results carry implications for analog-tuning of physical properties in future functional materials based on these compounds. [less ▲]

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