cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Energy decay in three-dimensional freely cooling granular gas
Creators: name: Pathak, Sudhir N.
name: Jabeen, Zahera
name: Das, Dibyendu
name: Rajesh, R.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The kinetic energy of a freely cooling granular gas decreases as a power law $t^{-θ}$ at large times $t$. Two theoretical conjectures exist for the exponent $θ$. One based on ballistic aggregation of compact spherical aggregates predicts $θ= 2d/(d+2)$ in $d$ dimensions. The other based on Burgers equation describing anisotropic, extended clusters predicts $θ=d/2$ when $2\le d \le 4$. We do extensive simulations in three dimensions to find that while $θ$ is as predicted by ballistic aggregation, the cluster statistics and velocity distribution differ from it. Thus, the freely cooling granular gas fits to neither the ballistic aggregation or a Burgers equation description.
description: 5 pages, 5 figures
An adaptive safety layer with hard constraints for safe reinforcement learning in multi-energy management systems
Creators: name: Ceusters, Glenn
name: Putratama, Muhammad Andy
name: Franke, Rüdiger
name: Nowé, Ann
name: Messagie, Maarten
Publisher: name: arXiv
Year: 2023
Subjects: subject: Systems and Control (eess.SY)
subject: Artificial Intelligence (cs.AI)
subject: Machine Learning (cs.LG)
subject: Optimization and Control (math.OC)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Safe reinforcement learning (RL) with hard constraint guarantees is a promising optimal control direction for multi-energy management systems. It only requires the environment-specific constraint functions itself a priori and not a complete model. The project-specific upfront and ongoing engineering efforts are therefore still reduced, better representations of the underlying system dynamics can still be learnt, and modelling bias is kept to a minimum. However, even the constraint functions alone are not always trivial to accurately provide in advance, leading to potentially unsafe behaviour. In this paper, we present two novel advancements: (I) combining the OptLayer and SafeFallback method, named OptLayerPolicy, to increase the initial utility while keeping a high sample efficiency and the possibility to formulate equality constraints. (II) introducing self-improving hard constraints, to increase the accuracy of the constraint functions as more and new data becomes available so that better policies can be learnt. Both advancements keep the constraint formulation decoupled from the RL formulation, so new (presumably better) RL algorithms can act as drop-in replacements. We have shown that, in a simulated multi-energy system case study, the initial utility is increased to 92.4% (OptLayerPolicy) compared to 86.1% (OptLayer) and that the policy after training is increased to 104.9% (GreyOptLayerPolicy) compared to 103.4% (OptLayer) - all relative to a vanilla RL benchmark. Although introducing surrogate functions into the optimisation problem requires special attention, we conclude that the newly presented GreyOptLayerPolicy method is the most advantageous.
description: post-print
The Next Generation Virgo Cluster Survey - Infrared (NGVS-IR): I. A new Near-UV/Optical/Near-IR Globular Cluster selection tool
Creators: name: Muñoz, Roberto P.
name: Puzia, Thomas H.
name: Lançon, Ariane
name: Peng, Eric W.
name: Côté, Patrick
name: Ferrarese, Laura
name: Blakeslee, John P.
name: Mei, Simona
name: Cuillandre, Jean-Charles
name: Hudelot, Patrick
name: Courteau, Stéphane
name: Duc, Pierre-Alain
name: Balogh, Michael L.
name: Boselli, Alessandro
name: Bournaud, Frédéric
name: Carlberg, Raymond G.
name: Chapman, Scott C.
name: Durrell, Patrick
name: Eigenthaler, Paul
name: Emsellem, Eric
name: Gavazzi, Giuseppe
name: Gwyn, Stephen
name: Huertas-Company, Marc
name: Ilbert, Olivier
name: Jordán, Andrés
name: Läsker, Ronald
name: Licitra, Rossella
name: Liu, Chengze
name: MacArthur, Lauren
name: McConnachie, Alan
name: McCracken, Henry Joy
name: Mellier, Yannick
name: Peng, Chien Y.
name: Raichoor, Anand
name: Taylor, Matthew A.
name: Tonry, John L.
name: Tully, R. Brent
name: Zhang, Hongxin
Publisher: name: arXiv
Year: 2013
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The NGVS-IR project (Next Generation Virgo Survey - Infrared) is a contiguous near-infrared imaging survey of the Virgo cluster of galaxies. It complements the optical wide-field survey of Virgo (NGVS). The current state of NGVS-IR consists of Ks-band imaging of 4 deg^2 centered on M87, and J and Ks-band imaging of 16 deg^2 covering the region between M49 and M87. In this paper, we present the observations of the central 4 deg^2 centered on Virgo's core region. The data were acquired with WIRCam on the Canada-France-Hawaii Telescope and the total integration time was 41 hours distributed in 34 contiguous tiles. A survey-specific strategy was designed to account for extended galaxies while still measuring accurate sky brightness within the survey area. The average 5σlimiting magnitude is Ks=24.4 AB mag and the 50% completeness limit is Ks=23.75 AB mag for point source detections, when using only images with better than 0.7" seeing (median seeing 0.54"). Star clusters are marginally resolved in these image stacks, and Virgo galaxies with μ_Ks=24.4 AB mag arcsec^-2 are detected. Combining the Ks data with optical and ultraviolet data, we build the uiK color-color diagram which allows a very clean color-based selection of globular clusters in Virgo. This diagnostic plot will provide reliable globular cluster candidates for spectroscopic follow-up campaigns needed to continue the exploration of Virgo's photometric and kinematic sub-structures, and will help the design of future searches for globular clusters in extragalactic systems. Equipped with this powerful new tool, future NGVS-IR investigations based on the uiK diagram will address the mapping and analysis of extended structures and compact stellar systems in and around Virgo galaxies.
description: 23 pages, 18 figures. Accepted for publication in ApJS
GUILLAIN-BARRE SYNDROME WITH BULBAR DISORDERS
Creators: name: Kudratov, Feruz
Publisher: name: Zenodo
Year: 2023

description: Bulbar disorders in the onset of Guillain-Barre syndrome (GBS) are rare and create diagnostic difficulties. A 50-55-year-old patient was hospitalized due to the development of dysarthria, ataxia, nasolalia, paresthesia and increased drowsiness, which reached the greatest severity after a day. An atypical variant of GBS was diagnosed. According to its manifestations, it corresponded to "acute bulbar paralysis plus". The peculiarity was the absence of an increase in protein in CSF by the end of the 2nd week of the disease and the absence of antibodies to gangliosides in the blood. Treatment included plasmapheresis. After a month, all clinical symptoms regressed. GBS in atypical cases can manifest with bulbar disorders and ataxia, which must be taken into account in the differential diagnosis with a stem stroke.
Testing the data framework for an AI algorithm in preparation for high data rate X-ray facilities
Creators: name: Chen, Hongwei
name: Chitturi, Sathya R.
name: Plumley, Rajan
name: Shen, Lingjia
name: Drucker, Nathan C.
name: Burdet, Nicolas
name: Peng, Cheng
name: Mardanya, Sougata
name: Ratner, Daniel
name: Mishra, Aashwin
name: Yoon, Chun Hong
name: Song, Sanghoon
name: Chollet, Matthieu
name: Fabbris, Gilberto
name: Dunne, Mike
name: Nelson, Silke
name: Li, Mingda
name: Lindenberg, Aaron
name: Jia, Chunjing
name: Nashed, Youssef
name: Bansil, Arun
name: Chowdhury, Sugata
name: Feiguin, Adrian E.
name: Turner, Joshua J.
name: Thayer, Jana B.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: The advent of next-generation X-ray free electron lasers will be capable of delivering X-rays at a repetition rate approaching 1 MHz continuously. This will require the development of data systems to handle experiments at these type of facilities, especially for high throughput applications, such as femtosecond X-ray crystallography and X-ray photon fluctuation spectroscopy. Here, we demonstrate a framework which captures single shot X-ray data at the LCLS and implements a machine-learning algorithm to automatically extract the contrast parameter from the collected data. We measure the time required to return the results and assess the feasibility of using this framework at high data volume. We use this experiment to determine the feasibility of solutions for `live' data analysis at the MHz repetition rate.
Towards trustworthy multi-modal motion prediction: Holistic evaluation and interpretability of outputs
Creators: name: Limeros, Sandra Carrasco
name: Majchrowska, Sylwia
name: Johnander, Joakim
name: Petersson, Christoffer
name: Sotelo, Miguel Ángel
name: Llorca, David Fernández
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Predicting the motion of other road agents enables autonomous vehicles to perform safe and efficient path planning. This task is very complex, as the behaviour of road agents depends on many factors and the number of possible future trajectories can be considerable (multi-modal). Most prior approaches proposed to address multi-modal motion prediction are based on complex machine learning systems that have limited interpretability. Moreover, the metrics used in current benchmarks do not evaluate all aspects of the problem, such as the diversity and admissibility of the output. In this work, we aim to advance towards the design of trustworthy motion prediction systems, based on some of the requirements for the design of Trustworthy Artificial Intelligence. We focus on evaluation criteria, robustness, and interpretability of outputs. First, we comprehensively analyse the evaluation metrics, identify the main gaps of current benchmarks, and propose a new holistic evaluation framework. We then introduce a method for the assessment of spatial and temporal robustness by simulating noise in the perception system. To enhance the interpretability of the outputs and generate more balanced results in the proposed evaluation framework, we propose an intent prediction layer that can be attached to multi-modal motion prediction models. The effectiveness of this approach is assessed through a survey that explores different elements in the visualization of the multi-modal trajectories and intentions. The proposed approach and findings make a significant contribution to the development of trustworthy motion prediction systems for autonomous vehicles, advancing the field towards greater safety and reliability.
description: 16 pages, 7 figures, 6 tables
Coherent error threshold for surface codes from Majorana delocalization
Creators: name: Venn, Florian
name: Behrends, Jan
name: Béri, Benjamin
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Statistical mechanics mappings provide key insights on quantum error correction. However, existing mappings assume incoherent noise, thus ignoring coherent errors due to, e.g., spurious gate rotations. We map the surface code with coherent errors, taken as $X$- or $Z$-rotations (replacing bit or phase flips), to a two-dimensional (2D) Ising model with complex couplings, and further to a 2D Majorana scattering network. Our mappings reveal both commonalities and qualitative differences in correcting coherent and incoherent errors. For both, the error-correcting phase maps, as we explicitly show by linking 2D networks to 1D fermions, to a $\mathbb{Z}_2$-nontrivial 2D insulator. However, beyond a rotation angle $ϕ_\text{th}$, instead of a $\mathbb{Z}_2$-trivial insulator as for incoherent errors, coherent errors map to a Majorana metal. This $ϕ_\text{th}$ is the theoretically achievable storage threshold. We numerically find $ϕ_\text{th}\approx0.14π$. The corresponding bit-flip rate $\sin^2(ϕ_\text{th})\approx 0.18$ exceeds the known incoherent threshold $p_\text{th}\approx0.11$.
description: 12 pages, 9 figures; v2: Supplemental Material expanded, incl. a section on the decoherence of logical noise. Accepted manuscript
Better Together: The Complex Interplay Between Radiative Cooling and Magnetic Draping
Creators: name: Hidalgo-Pineda, Fernando
name: Farber, Ryan Jeffrey
name: Gronke, Max
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Rapidly outflowing cold H-I gas is ubiquitously observed to be co-spatial with a hot phase in galactic winds, yet the ablation time of cold gas by the hot phase should be much shorter than the acceleration time. Previous work showed efficient radiative cooling enables clouds to survive in hot galactic winds under certain conditions, as can magnetic fields even in purely adiabatic simulations for sufficiently small density contrasts between the wind and cloud. In this work, we study the interplay between radiative cooling and magnetic draping via three dimensional radiative magnetohydrodynamic simulations with perpendicular ambient fields and tangled internal cloud fields. We find magnetic fields decrease the critical cloud radius for survival by two orders of magnitude (i.e., to sub-pc scales) in the strongly magnetized ($β_{\rm wind}=1$) case. Our results show magnetic fields (i) accelerate cloud entrainment through magnetic draping, (ii) can cause faster cloud destruction in cases of inefficient radiative cooling, (iii) do not significantly suppress mass growth for efficiently cooling clouds, and, crucially, in combination with radiative cooling (iv) reduce the average overdensity by providing non-thermal pressure support of the cold gas. This substantially reduces the acceleration time compared to the destruction time (more than due to draping alone), enhancing cloud survival. Our results may help to explain the cold, tiny, rapidly outflowing cold gas observed in galactic winds and the subsequent high covering fraction of cold material in galactic halos.
description: 15 pages, 9 figures + Appendices. Accepted for publication in MNRAS
Growth and micromagnetism of self-assembled epitaxial fcc(111) cobalt dots
Creators: name: Fruchart, Olivier
name: Masseboeuf, Aurélien
name: Toussaint, Jean-Christophe
name: Bayle-Guillemaud, Pascale
Publisher: name: arXiv
Year: 2013
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We developed the self-assembly of epitaxial submicrometer-sized face-centered-cubic (fcc) Co(111) dots using pulsed laser deposition. The dots display atomically-fl at facets, from which the ratios of surface and interface energies for fcc Co are deduced. Zero- field magnetic structures are investigated with magnetic force and lorentz microscopies, revealing vortex-based flux-closure patterns. A good agreement is found with micromagnetic simulations.
Academic Writing with GPT-3.5: Reflections on Practices, Efficacy and Transparency
Creators: name: Buruk, Oğuz 'Oz'
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: Human-Computer Interaction (cs.HC)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: The debate around the use of GPT 3.5 has been a popular topic among academics since the release of ChatGPT. Whilst some have argued for the advantages of GPT 3.5 in enhancing academic writing, others have raised concerns such as plagiarism, the spread of false information, and ecological issues. The need for finding ways to use GPT 3.5 models transparently has been voiced, and suggestions have been made on social media as to how to use GPT 3.5 models in a smart way. Nevertheless, to date, there is a lack of literature which clearly outlines how to use GPT 3.5 models in academic writing, how effective they are, and how to use them transparently. To address this, I conducted a personal experience experiment with GPT 3.5, specifically by using OpenAI text davinci 003 model, for writing this article. I identified five ways of using GPT 3.5: Chunk Stylist, Bullet to Paragraph, Talk Textualizer, Research Buddy, and Polisher. I reflected on their efficacy, and commented on their potential impact on writing ethics. Additionally, I provided a comprehensive document which shows the prompts I used, results I got from GPT 3.5, the final edits and visually compares those by showing the differences in percentages.
description: 9 Pages, 84 Pages of Appendix
Density control of GaN nanowires at the wafer scale using self-assembled SiN$_x$ patches on sputtered TiN(111)
Creators: name: Auzelle, Thomas
name: Oliva, Miriam
name: John, Philipp
name: Ramsteiner, Manfred
name: Geelhaar, Lutz
name: Brandt, Oliver
Publisher: name: arXiv
Year: 2022
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: The self-assembly of heteroepitaxial GaN nanowires using either molecular beam epitaxy (MBE) or metal-organic vapor phase epitaxy (MOVPE) mostly results in wafer-scale ensembles with ultrahigh ($>10$ $μ$m$^{-2}$) or ultralow ($<1$ $μ$m$^{-2}$) densities, respectively. A simple means to tune the density of well-developed nanowire ensembles between these two extremes is generally lacking. Here, we examine the self-assembly of SiN$_x$ patches on TiN(111) substrates which are eventually acting as seeds for the growth of GaN nanowires. We first found that if prepared by reactive sputtering, the TiN surface is characterized by \{100\} facets for which the GaN incubation time is extremely long. Fast GaN nucleation is only obtained after deposition of a sub-monolayer of SiN$_x$ atoms prior to the GaN growth. By varying the amount of pre-deposited SiN$_x$, the GaN nanowire density could be tuned by three orders of magnitude with excellent uniformity over the entire wafer, bridging the density regimes conventionally attainable by direct self-assembly with MBE or MOVPE. The analysis of the nanowire morphology agrees with a nucleation of the GaN nanowires on nanometric SiN$_x$ patches. The photoluminescence analysis of single freestanding GaN nanowires reveals a band edge luminescence dominated by excitonic transitions that are broad and blue shifted compared to bulk GaN, an effect that is related to the small nanowire diameter and to the presence of a thick native oxide. The approach developed here can be principally used for tuning the density of most III-V semiconductors nucleus grown on inert surfaces like 2D materials.
Controlling collective dynamics in complex, minority-game resource-allocation systems
Creators: name: Zhang, Ji-Qiang
name: Huang, Zi-Gang
name: Huang, Zi-Gang
name: Huang, Liang
name: Huang, Tie-Qiao
name: Lai, Ying-Cheng
Publisher: name: arXiv
Year: 2013
Subjects: subject: Physics and Society (physics.soc-ph)
subject: FOS: Physical sciences

description: Resource allocation takes place in various kinds of real-world complex systems, such as the traffic systems, social services institutions or organizations, or even the ecosystems. The fundamental principle underlying complex resource-allocation dynamics is Boolean interactions associated with minority games, as resources are generally limited and agents tend to choose the least used resource based on available information. A common but harmful dynamical behavior in resource-allocation systems is herding, where there are time intervals during which a large majority of the agents compete for a few resources, leaving many other resources unused. Ac- companying the herd behavior is thus strong fluctuations with time in the number of resources being used. In this paper, we articulate and establish that an intuitive control strategy, namely pinning control, is effective at harnessing the herding dynamics. In particular, by fixing the choices of resources for a few agents while leaving majority of the agents free, herding can be eliminated completely. Our investigation is systematic in that we consider random and targeted pinning and a variety of network topologies, and we carry out a comprehensive analysis in the framework of mean-field theory to understand the working of control. The basic philosophy is then that, when a few agents waive their freedom to choose resources by receiving sufficient incentives, majority of the agents benefit in that they will make fair, efficient, and effective use of the available resources. Our work represents a basic and general framework to address the fundamental issue of fluctuations in complex dynamical systems with significant applications to social, economical and political systems.
description: 9 pages,4 figures
Quantum transport theory of hybrid superconducting systems
Creators: name: Yao, Chuan-Zhe
name: Lai, Hon-Lam
name: Zhang, Wei-Min
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a quantum transport theory for hybrid superconducting systems based on our exact master equation approach. The total transient transport current is decomposed into components that describe coherent transports through different paths of particle and hole channels. We show that the coherent transports are resultant interferences of numerous repeated tunneling processes and cannot be rendered as a simple normal transmission or Andreev reflection as usually described quantum transport involving superconductivity. As a practical application, we find that the coherent transport currents passing through a pair of well-separated Majorana zero modes vanish due to the totally destructive interference between the particle and hole channels.
MaNGA DynPop -- III. Stellar dynamics versus stellar population relations in 6000 early-type and spiral galaxies: Fundamental Plane, mass-to-light ratios, total density slopes, and dark matter fractions
Creators: name: Zhu, Kai
name: Lu, Shengdong
name: Cappellari, Michele
name: Li, Ran
name: Mao, Shude
name: Gao, Liang
name: Ge, Junqiang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present dynamical scaling relations, combined with the stellar population properties, for a subsample of about 6000 nearby galaxies with the most reliable dynamical models extracted from the full MaNGA sample of 10K galaxies. We show that the inclination-corrected mass plane (MP) for both early-type galaxies (ETGs) and late-type galaxies (LTGs), which links dynamical mass, projected half-light radius $R_{\rm e}$, and the second stellar velocity moment $σ_{\rm e}$ within $R_{\rm e}$, satisfies the virial theorem and is even tighter than the uncorrected one. We find a clear parabolic relation between $\lg(M/L)_{\rm e}$, the total mass-to-light ratio within a sphere of radius $R_{\rm e}$, and $\lgσ_{\rm e}$, with the $M/L$ increasing with $σ_{\rm e}$ and for older stellar populations. However, the relation for ETGs is linear and the one for the youngest galaxies is constant. We confirm and improve the relation between average logarithmic total density slopes $\overline{γ_{\rm T}}$ and $σ_{\rm e}$: $\overline{γ_{\rm T}}$ become steeper with increasing $σ_{\rm e}$ until $\lg(σ_{\rm e}/{\rm km\,s^{-1}})\approx 2.2$ and then remain constant around $\overline{γ_{\rm T}}\approx -2.2$. The $\overline{γ_{\rm T}}-σ_{\rm e}$ variation is larger for LTGs than ETGs. At fixed $σ_{\rm e}$ the total density profiles steepen with galaxy age and for ETGs. We find generally low dark matter fractions, median $f_{\rm DM}(
description: 26 pages, 21 figures, 1 table; Accepted by MNRAS
The Diffuse Galactic Far-Ultraviolet Sky
Creators: name: Hamden, Erika
name: Schiminovich, David
name: Seibert, Mark
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present an all sky map of the diffuse Galactic far ultraviolet (1344-1786 Angstroms) background using GALEX data, covering 65% of the sky with 11.79 arcmin square pixels. We investigate the dependence of the background on Galactic coordinates, finding that a standard cosecant model of intensity is not a valid fit. Furthermore, we compare our map to Galactic all sky maps of 100 micron emission, N_HI column, and H-alpha intensity. We measure a consistent low level FUV intensity at zero-points for other Galactic quantities, indicating a 300 CU non-scattered isotropic component to the diffuse FUV. There is also a linear relationship between FUV and 100 micron emission below 100 micron values of 8 MJy/sr. We find a similar linear relationship between FUV and NHI below 10^21 square cm. The relationship between FUV and H-alpha intensity has no such constant cutoff. For all Galactic quantities, the slope of the linear portion of the relationship decreases with Galactic latitude. A modified cosecant model, taking into account dust scattering asymmetry and albedo, is able to accurately fit the diffuse FUV at latitudes above 20 degrees. The best fit model indicates an albedo, a, of 0.62 +- 0.04 and a scattering asymmetry function, g, of 0.78 +- 0.05. Deviations from the model fit may indicate regions of excess FUV emission from fluorescence or shock fronts, while low latitude regions with depressed FUV emission are likely the result of self-shielding dusty clouds.
description: 15 pages, 19 Figures, Accepted for publication by ApJ
title: Annual Report 2021: Cooperation between the German Focal Point of the European Food Safety Authority and the German Article 36 Network
Creators: name: Bergelt, Sophia
name: Lechleider, Marina
name: Udagawa, Kei
name: Zwede, Benthe
name: Schöne, Julia
name: Gollnick, Nicole
name: Lahaniatis, Majlinda
Publisher: name: Bundesbehörden und Einrichtungen im Geschäftsbereich des Bundesministeriums für Ernährung und Landwirtschaft (BMEL)
Year: 2023
Subjects: subject: 610

description: BfR-Wissenschaft
Non-linear optics at twist interfaces in h-BN/SiC heterostructures
Creators: name: Biswas, Abhijit
name: Xu, Rui
name: Alvarez, Gustavo A.
name: Zhang, Jin
name: Christiansen-Salameh, Joyce
name: Puthirath, Anand B.
name: Burns, Kory
name: Hachtel, Jordan A.
name: Li, Tao
name: Iyengar, Sathvik Ajay
name: Gray, Tia
name: Li, Chenxi
name: Zhang, Xiang
name: Kannan, Harikishan
name: Elkins, Jacob
name: Pieshkov, Tymofii S.
name: Vajtai, Robert
name: Birdwell, A. Glen
name: Neupane, Mahesh R.
name: Garratt, Elias J.
name: Ivanov, Tony
name: Pate, Bradford B.
name: Zhao, Yuji
name: Zhu, Hanyu
name: Tian, Zhiting
name: Rubio, Angel
name: Ajayan, Pulickel M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Understanding the emergent electronic structure in twisted atomically thin layers has led to the exciting field of twistronics. However, practical applications of such systems are challenging since the specific angular correlations between the layers must be precisely controlled and the layers have to be single crystalline with uniform atomic ordering. Here, we suggest an alternative, simple and scalable approach where nanocrystalline two-dimensional (2D) film on three-dimensional (3D) substrates yield twisted-interface-dependent properties. Ultrawide-bandgap hexagonal boron nitride (h-BN) thin films are directly grown on high in-plane lattice mismatched wide-bandgap silicon carbide (4H-SiC) substrates to explore the twist-dependent structure-property correlations. Concurrently, nanocrystalline h-BN thin film shows strong non-linear second-harmonic generation and ultra-low cross-plane thermal conductivity at room temperature, which are attributed to the twisted domain edges between van der Waals stacked nanocrystals with random in-plane orientations. First-principles calculations based on time-dependent density functional theory manifest strong even-order optical nonlinearity in twisted h-BN layers. Our work unveils that directly deposited 2D nanocrystalline thin film on 3D substrates could provide easily accessible twist-interfaces, therefore enabling a simple and scalable approach to utilize the 2D-twistronics integrated in 3D material devices for next-generation nanotechnology.
description: 33 pages, 4 figures
Majorana bound states in germanium Josephson junctions via phase control
Creators: name: Luethi, Melina
name: Legg, Henry F.
name: Laubscher, Katharina
name: Loss, Daniel
name: Klinovaja, Jelena
Publisher: name: arXiv
Year: 2023
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We consider superconductor-normal-superconductor-normal-superconductor (SNSNS) planar Josephson junctions in hole systems with spin-orbit interaction that is cubic in momentum (CSOI). Using only the superconducting phase difference, we find parameter regimes where junctions of experimentally achievable transparency can enter a topological superconducting phase with Majorana bound states (MBSs) at the junction ends. In planar germanium heterostructures CSOI can be the dominant form of SOI and extremely strong. We show analytically and numerically that, within experimental regimes, our results provide an achievable roadmap for a new MBS platform with low disorder, minimal magnetic fields, and very strong spin-orbit interaction, overcoming many of the key deficiencies that have so far prevented the conclusive observation of MBSs.
description: main text: 4 pages, 3 figures. Appendix: 8 pages, 7 figures
Quantum Lyapunov exponent in dissipative systems
Creators: name: Bergamasco, Pablo D.
name: Carlo, Gabriel G.
name: Rivas, Alejandro M. F.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: The out-of-time order correlator (OTOC) has been widely studied in closed quantum systems. However, there are very few studies for open systems and they are mainly focused on isolating the effects of scrambling from those of decoherence. Adopting a different point of view, we study the interplay between these two processes. This proves crucial in order to explain the OTOC behavior when a phase space contracting dissipation is present, ubiquitous not only in real life quantum devices but in the dynamical systems area. The OTOC decay rate is closely related to the classical Lyapunov exponent -- with some differences -- and more sensitive in order to distinguish the chaotic from the regular behavior than other measures. On the other hand, it reveals as a generally simple function of the longest lived eigenvalues of the quantum evolution operator. We find no simple connection with the Ruelle-Pollicott resonances, but by adding Gaussian noise of $\hbar_{\text{eff}}$ size to the classical system we recover the OTOC decay rate, being this a consequence of the correspondence principle put forward in [Physical Review Letters 108 210605 (2012) and Physical Review E 99 042214 (2019)]
description: 5 pages, 7 figures
Migraine and obesity: what is the real direction of their association?
Creators: name: Jahromi, Soodeh Razeghi
name: Martami, Fahimeh
name: Soltani, Kasra Morad
name: Togha, Mansoureh
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Genetics
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 19999 Mathematical Sciences not elsewhere classified
subject: FOS: Mathematics
subject: Cancer
subject: Science Policy

description: In recent decades, studies have addressed the issue of how migraine and obesity are related and have suggested obesity as a risk factor for migraine headache. However, the exact direction of this relationship remains under debate. In this review, the authors summarize the evidence that have suggested migraine as a risk factor for obesity and overweightness. This article reviews the results of the previous research published on PubMed and Scopus databases (from 2000 to 2020) concerning the association between migraine and obesity to determine the actual direction of their association. Special attention has been given to the common mechanistic pathways involved in the pathophysiology of migraine and obesity. The majority of research conducted thus far has considered obesity as a risk factor for migraine. However, because of the cross-sectional design of available research, we cannot be certain of the proposed direction of this association. There is evidence supporting the hypothesis that obesity can serve as a consequence of migraine through the effects of neuropeptides, inflammatory mediators, adipokines, gut microbiota and modifications in eating behavior and lifestyle. However, the real direction of the relationship between migraine and obesity should be further investigated in large prospective studies.
The Formation and Evolution of Small Star Clusters
Creators: name: Kirk, Helen
name: Offner, Stella S. R.
name: Redmond, Kayla
Publisher: name: arXiv
Year: 2014
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Recent observations show that small, young, stellar groupings of ~10 to 40 members tend of have a centrally-located most massive member, reminiscent of mass segregation seen in large clustered systems. Here, we analyze hydrodynamic simulations which form small clusters and analyze their properties in a manner identical to the observations. We find that the simulated clusters possess similar properties to the observed clusters, including a tendency to exhibit mass segregation. In the simulations, the central location of the most massive member is not due to dynamical evolution, since there is little interaction between the cluster members. Instead, the most massive cluster member appears to form at the center. We also find that the more massive stars in the cluster form at slightly earlier times.
description: Accepted for publication in MNRAS; 17 pages
Time-frequency analysis of event-related brain recordings: Connecting power of evoked potential and inter-trial coherence
Creators: name: Benhamou, Jonas
name: Van Quyen, Michel Le
name: Marrelec, Guillaume
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Quantitative Methods (q-bio.QM)
subject: FOS: Biological sciences

description: Objective. In neuroscience, time-frequency analysis has been used to get insight into brain rhythms from brain recordings. In event-related protocols, one applies it to investigate how the brain responds to a stimulation repeated over many trials. In this framework, three measures have been considered: the amplitude of the transform for each single trial averaged across trials, avgAMP; inter-trial phase coherence, ITC; and the power of the evoked potential transform, POWavg. These three measures are sensitive to different aspects of event-related responses, ITC and POWavg sharing a common sensitivity to phase resetting phenomena. Methods. In the present manuscript, we further investigated the connection between ITC and POWavg using theoretical calculations, a simulation study and analysis of experimental data. Results. We derived exact expressions for the relationship between POWavg and ITC in the particular case of the S-transform of an oscillatory signal. In the more general case, we showed that POWavg and ITC are connected through a relationship that roughly reads $\mathrm{POWavg} \approx \mathrm{avgAMP}^2 \times \mathrm{ITC}^2$. This result was confirmed on simulations. We finally compared the theoretical prediction with results from real data. Conclusion. We showed that POWavg and ITC are related through an approximate, simple relationship that also involves avgAMP. Significance. The presented relationship between POWavg, ITC, and avgAMP confirms previous empirical evidence and provides a novel perspective to investigate evoked brain rhythms. It may provide a significant refinement to the neuroscientific toolbox for studying evoked oscillations.
Techno-Economic Assessment in Communications: New Challenges
Creators: name: Bendicho, Carlos
name: Bendicho, Daniel
Publisher: name: arXiv
Year: 2023
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences
subject: C.2.0; C.2.1; C.2.3; C.2.6; C.2.m

description: This article shows a brief history of Techno-Economic Assessment (TEA) in Communications, a proposed redefinition of TEA as well as the new challenges derived from a dynamic context with cloud-native virtualized networks, the Helium Network & alike blockchain-based decentralized networks, the new network as a platform (NaaP) paradigm, carbon pricing, network sharing, and web3, metaverse and blockchain technologies. The authors formulate the research question and show the need to improve TEA models to integrate and manage all this increasing complexity. This paper also proposes the characteristics TEA models should have and their current degree of compliance for several use cases: 5G and beyond, software-defined wide area network (SD-WAN), secure access service edge (SASE), secure service edge (SSE), and cloud cybersecurity risk assessment. The authors also present TEA extensibility to request for proposals (RFP) processes and other industries, to conclude that there is an urgent need for agile and effective TEA in Comms that allows industrialization of agile decision-making for all market stakeholders to choose the optimal solution for any technology, scenario and use case.
description: 18 pages, 1 figure, 2 tables
UK medical cannabis registry: assessment of clinical outcomes in patients with headache disorders
Creators: name: Nicholas, Martha
name: Erridge, Simon
name: Bapir, Lara
name: Pillai, Manaswini
name: Dalavaye, Nishaanth
name: Holvey, Carl
name: Coomber, Ross
name: Rucker, James J
name: Weatherall, Mark W
name: Sodergren, Mikael H
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Medicine
subject: Cell Biology
subject: Pharmacology
subject: Science Policy
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Headache disorders are a common cause of disability and reduced health-related quality of life globally. Growing evidence supports the use of cannabis-based medicinal products (CBMPs) for chronic pain; however, a paucity of research specifically focuses on CBMPs’ efficacy and safety in headache disorders. This study aims to assess changes in validated patient-reported outcome measures (PROMs) in patients with headaches prescribed CBMPs and investigate the clinical safety in this population. A case series of the UK Medical Cannabis Registry was conducted. Primary outcomes were changes from baseline in PROMs (Headache Impact Test-6 (HIT-6), Migraine Disability Assessment (MIDAS), EQ-5D-5L, Generalized Anxiety Disorder-7 (GAD-7) questionnaire and Single-Item Sleep Quality Scale (SQS)) at 1-, 3-, and 6-months follow-up. P-values <0.050 were deemed statistically significant. Ninety-seven patients were identified for inclusion. Improvements in HIT-6, MIDAS, EQ-5D-5L and SQS were observed at 1-, 3-, and 6-months (p < 0.005) follow-up. GAD-7 improved at 1- and 3-months (p < 0.050). Seventeen (17.5%) patients experienced a total of 113 (116.5%) adverse events. Improvements in headache/migraine-specific PROMs and general health-related quality of life were associated with the initiation of CBMPs in patients with headache disorders. Cautious interpretation of results is necessary, and randomized control trials are required to ascertain causality.
Stabilizer entropy dynamics after a quantum quench
Creators: name: Rattacaso, Davide
name: Leone, Lorenzo
name: Oliviero, Salvatore F. E.
name: Hamma, Alioscia
Publisher: name: arXiv
Year: 2023
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Stabilizer entropies (SE) measure deviations from stabilizer resources and as such are a fundamental ingredient for quantum advantage. In particular, the interplay of SE and entanglement is at the root of the complexity of classically simulating quantum many-body systems. In this paper, we study the dynamics of SE in a quantum many-body system away from the equilibrium after a quantum quench in an integrable system. We obtain two main results: (i) we show that SE, despite being an L-extensive quantity, equilibrates in a time that scales at most linearly with the subsystem size; and (ii) we show that there is a SE length increasing linearly in time, akin to correlations and entanglement spreading.
description: 13 pages, 9 figures
Engineering field-insensitive molecular clock transitions for symmetry violation searches
Creators: name: Takahashi, Yuiki
name: Zhang, Chi
name: Jadbabaie, Arian
name: Hutzler, Nicholas R.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Molecules are a powerful platform to probe fundamental symmetry violations beyond the Standard Model, as they offer both large amplification factors and robustness against systematic errors. As experimental sensitivities improve, it is important to develop new methods to suppress sensitivity to external electromagnetic fields, as limits on the ability to control these fields are a major experimental concern. Here we show that sensitivity to both external magnetic and electric fields can be simultaneously suppressed using engineered radio frequency, microwave, or two-photon transitions that maintain large amplification of CP-violating effects. By performing a clock measurement on these transitions, CP-violating observables including the electron electric dipole moment, nuclear Schiff moment, and magnetic quadrupole moment can be measured with suppression of external field sensitivity of $\gtrsim$100 generically, and even more in many cases. Furthermore, the method is compatible with traditional Ramsey measurements, offers internal co-magnetometry, and is useful for systems with large angular momentum commonly present in molecular searches for nuclear CP-violation.
Foundations of Garside Theory
Creators: name: Dehornoy, Patrick
name: Digne, Francois
name: Godelle, Eddy
name: Krammer, Daan
name: Michel, Jean
Publisher: name: arXiv
Year: 2013
Subjects: subject: Group Theory (math.GR)
subject: FOS: Mathematics

description: This text consists of the introduction, table of contents, and bibliography of a long manuscript (703 pages) that is currently submitted for publication. This manuscript develops an extension of Garside's approach to braid groups and provides a unified treatment for the various algebraic structures that appear in this context. The complete text can be found at http://www.math.unicaen.fr/~garside/Garside.pdf.
Spontaneous scale symmetry breaking at high temperature
Creators: name: Lalak, Zygmunt
name: Michalak, Paulina
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We consider a scale symmetric extension of the Standard Model Higgs scalar sector. The new sector, dilaton, is responsible for the generation of mass scales and may have geometric origin in the Weyl gravity $\tilde{R}^2$ term. We show how temperature as a mass scale breaks scale symmetry explicitly and through a nonvanishing thermal vev. In addition we demonstrate that cosmological evolution of the dilaton-Higgs system can lead to late time mass scales, which agree with the Standard Model.
Stemmers for Tamil Language: Performance Analysis
Creators: name: Thangarasu, M.
name: Manavalan, R.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: Stemming is the process of extracting root word from the given inflection word and also plays significant role in numerous application of Natural Language Processing (NLP). Tamil Language raises several challenges to NLP, since it has rich morphological patterns than other languages. The rule based approach light-stemmer is proposed in this paper, to find stem word for given inflection Tamil word. The performance of proposed approach is compared to a rule based suffix removal stemmer based on correctly and incorrectly predicted. The experimental result clearly show that the proposed approach light stemmer for Tamil language perform better than suffix removal stemmer and also more effective in Information Retrieval System (IRS).
Higher-order time domain boundary elements for elastodynamics -- graded meshes and hp versions
Creators: name: Aimi, Alessandra
name: Di Credico, Giulia
name: Gimperlein, Heiko
name: Stephan, Ernst P.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Numerical Analysis (math.NA)
subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: The solution to the elastodynamic equation in the exterior of a polyhedral domain or a screen exhibits singular behavior from the corners and edges. The detailed expansion of the singularities implies quasi-optimal estimates for piecewise polynomial approximations of the Dirichlet trace of the solution and the traction. The results are applied to hp and graded versions of the time domain boundary element method for the weakly singular and the hypersingular integral equations. Numerical examples confirm the theoretical results for the Dirichlet and Neumann problems for screens and for polygonal domains in 2d. They exhibit the expected quasi-optimal convergence rates and the singular behavior of the solutions.
description: 53 pages, 17 figures, to appear in Numerische Mathematik
Radiative p11b capture at astrophysical energies
Creators: name: Dubovichenko, S. B.
name: Burkova, N. A.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: In the framework of the modified potential cluster model with forbidden states the possibility of describing the available experimental data on the total cross sections and astrophysical S-factor for p11B radiative capture to the ground state of 12C was treated at astrophysical energies.
description: 10p., 4 fig., 30 ref. arXiv admin note: text overlap with arXiv:1312.4274