cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Holographic entropy production in a Bjorken expanding hot and dense strongly coupled quantum fluid
Creators: name: Rougemont, Romulo
name: Barreto, Willians
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We analyze the time evolution of several physical observables, namely the pressure anisotropy, the scalar condensate, the charge density, and also, for the first time, the non-equilibrium entropy for a Bjorken expanding strongly coupled $\mathcal{N}=4$ Supersymmetric Yang-Mills plasma charged under an Abelian $U(1)$ subgroup of the global $SU(4)$ R-symmetry. This represents a far-from-equilibrium, hot and dense strongly coupled quantum fluid with a critical point in its phase diagram. For some sets of initial data preserving all the energy conditions, dynamically driven transient violations of the dominant and the weak energy conditions are observed when the plasma is still far from the hydrodynamic regime. The energy conditions violations get stronger at larger values of the chemical potential to temperature ratio, $μ/T$, indicating that those violations become more relevant as the strongly coupled quantum fluid approaches its critical regime. For some of those energy conditions violations, it is observed a clear correlation with different plateau structures formed in the far from equilibrium entropy, indicating the presence of transient, early time windows where the Bjorken expanding plasma has zero entropy production even while being far from equilibrium. The hydrodynamization of the pressure anisotropy and also the much later thermalization of the scalar condensate are generally found to be delayed, within small relative tolerances, as $μ/T$ is increased towards criticality. The value of $μ/T$ in the medium is enhanced by increasing its initial charge density, and/or also by reducing its initial energy density.
description: 47 pages, 30 figures, accepted for publication in Physical Review D
X-Ray Flashes in Recurrent Novae: M31N 2008-12a and the Implications of the Swift Non-detection
Creators: name: Kato, Mariko
name: Saio, Hideyuki
name: Henze, Martin
name: Ness, Jan-Uwe
name: Osborne, Julian P.
name: Page, Kim L.
name: Darnley, Matthew J.
name: Bode, Michael F.
name: Shafter, Allen W.
name: Hernanz, Margarita
name: Gehrels, Neil
name: Kennea, Jamie
name: Hachisu, Izumi
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Models of nova outbursts suggest that an X-ray flash should occur just after hydrogen ignition. However, this X-ray flash has never been observationally confirmed. We present four theoretical light curves of the X-ray flash for two very massive white dwarfs (WDs) of 1.380 and 1.385 M_sun and for two recurrence periods of 0.5 and 1 years. The duration of the X-ray flash is shorter for a more massive WD and for a longer recurrence period. The shortest duration of 14 hours (0.6 days) among the four cases is obtained for the 1.385 M_sun WD with one year recurrence period. In general, a nova explosion is relatively weak for a very short recurrence period, which results in a rather slow evolution toward the optical peak. This slow timescale and the predictability of very short recurrence period novae give us a chance to observe X-ray flashes of recurrent novae. In this context, we report the first attempt, using the Swift observatory, to detect an X-ray flash of the recurrent nova M31N 2008-12a (0.5 or 1 year recurrence period), which resulted in the non-detection of X-ray emission during the period of 8 days before the optical detection. We discuss the impact of these observations on nova outburst theory. The X-ray flash is one of the last frontiers of nova studies and its detection is essentially important to understand the pre-optical-maximum phase. We encourage further observations.
description: 12 pages, including 9 figures and 3 tables. To appear in the Astrophysical Journal
Simulation a Close-to-Reality Synthetic Population of the Greater Accra Region
Creators: name: Frazier, Tyler J.
name: Alfons, Andreas
Publisher: name: Technische Universität Berlin
Year: 2011
Subjects: subject: 380 Handel, Kommunikation, Verkehr
subject: Greater Accra Urban Simulation System
subject: GAUSS
subject: Ghana
subject: simulation
subject: urban dynamics

description: The purpose of this research is to simulate a synthetic population of the Greater Accra Metropolitan Region (GAMA) from the 2005 Ghana Living Standards Survey (GLSS5) for use in the Greater Accra Urban Simulation System (GAUSS). A primary goal in simulating the synthetic population of GAMA is to employ a method which generates close-to-reality population data rather than repeatedly drawing samples. In order to generate close-to-reality synthetic data, combinations which were not represented in the original household survey but are likely to occur in the true population must occur in the synthetically generated data. The author estimates the conditional distributions with multinomial logistic regression models in order to simulate categorical and continuous variables. The simulation of random zeros as opposed to structural zeros, are also reflected in the synthetically generated Greater Accra population. One of the main purposes for avoiding pure replication of units from the underlying sample is because this generally leads to small variability of units within smaller subgroups, which results in an increase in unrealistic model behavior when population data is used as input for agent-based simulations of urban dynamics.
Modeling Other Minds: Scientists at a historic New England laboratory are trying to turn octopuses into the next experimental animals—they might transform biology itself
Creators: name: Lescaze, Zoë
Publisher: name: University of Chicago
Year: 2022
Subjects: subject: octopus
subject: model organism
subject: woods hole
subject: marine biological laboratory

description: This professional-track thesis, conceived as a piece of long-form journalism, examines attempts to develop cephalopods as model organisms with a wide range of biomedical research applications at the Marine Biological Laboratory in Woods Hole, Massachusetts. In doing so it explores the tensions between the viability of octopuses as analogues for humans, and how the very traits that make it potentially viable—resilience, intelligence, complex sociality, adaptability—are entwined with a vibrant social imagination of the species that threatens the possibility that it will truly become the next laboratory rat.
Periodicities of the RV Tau-type pulsating star DF Cygni: a combination of Kepler data with ground-based observations
Creators: name: Bódi, A.
name: Szatmáry, K.
name: Kiss, L. L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The RV Tauri stars constitute a small group of classical pulsating stars with some dozen known members in the Milky Way. The light variation is caused predominantly by pulsations, but these alone do not explain the full complexity of the light curves. High quality photometry of RV Tau-type stars is very rare. DF Cygni is the only member of this class of stars in the original Kepler field, hence allowing the most accurate photometric investigation of an RV Tauri star to date. The main goal is to analyse the periodicities of the RV Tauri-type star DF Cygni by combining four years of high-quality Kepler photometry with almost half a century of visual data collected by the American Association of Variable Star Observers. Kepler quarters of data have been stitched together to minimize the systematic effects of the space data. The mean levels have been matched with the AAVSO visual data. Both datasets have been submitted to Fourier and wavelet analyses, while the stability of the main pulsations has been studied with the O-C method and the analysis of the time-dependent amplitudes. DF Cygni shows a very rich behaviour on all time-scales. The slow variation has a period of 779.606 d and it has been remarkably coherent during the whole time-span of the combined data. On top of the long-term cycles the pulsations appear with a period of 24.925 d. Both types of light variation significantly fluctuate in time, with a constantly changing interplay of amplitude and phase modulations. The long-period change (i.e. the RVb signature) somewhat resembles the Long Secondary Period (LSP) phenomenon of the pulsating red giants, whereas the short-period pulsations are very similar to those of the Cepheid variables. Comparing the pulsation patterns with the latest models of Type-II Cepheids, we found evidence of strong non-linear effects directly observable in the Kepler light curve.
description: 8 pages, 9 figures, 1 table, accepted for publication in A&A
Pneumothorax, pneumomediastinum, and subcutaneous emphysema in hospitalized COVID-19 patients: incidence, clinical characteristics, and outcomes
Creators: name: Baptista, Aleksandra Murawska
name: De Frías, Jorge Sinclair
name: Singh, Trisha
name: Vasudhar, Ananya
name: Guzzino, Jacob
name: Khalili, Waheed
name: Tekin, Aysun
name: Bansal, Vikas
name: Kashyap, Rahul
name: Joyce, William J.
name: Lewis, Patricia A.
name: Sanghavi, Devang
name: Gavrancic, Tatjana
name: Franco, Pablo Moreno
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Space Science
subject: Medicine
subject: Pharmacology
subject: Chemical Sciences not elsewhere classified
subject: Immunology
subject: FOS: Clinical medicine
subject: Biological Sciences not elsewhere classified
subject: Developmental Biology
subject: Cancer
subject: Science Policy

description: Limited data is available on the incidence and outcomes of pneumothorax (PTX), pneumomediastinum (PNM), and subcutaneous emphysema (SCE) in COVID-19 patients. This study aimed to investigate the characteristics of these complications in hospitalized COVID-19 patients. A retrospective study was conducted, involving adult COVID-19 patients admitted to Mayo Clinic Florida from 03/2020–06/2022. Patients were divided into two groups based on the presence or absence of PTX/PNM/SCE 1926 hospitalized patients with COVID-19 were included, of which 518 were admitted to the ICU. The incidence of PTX/PNM/SCE was 6.3%. Patients with these complications were more likely to be male, Asian, and unvaccinated. Conversely, they were less likely to have chronic obstructive pulmonary disease. Patients who developed PTX/PNM/SCE after 72 hours of admission were more likely to receive high-dose corticosteroids and for an extended duration. The affected group had an adjusted odds ratio for in-hospital mortality of 13.32 (95%CI, 8.19–21.59) and ICU admission of 9.14 (95%CI, 5.3–12.78) compared to the unaffected group. Although the occurrence of PTX/PNM/SCE in hospitalized COVID-19 patients was rare, it was associated with worse outcomes. Corticosteroids may contribute to the pathogenesis of these complications; however, further studies are needed to investigate this relationship in more detail.
C/O and Mg/Si Ratios of Stars in the Solar Neighborhood
Creators: name: Brewer, John M.
name: Fischer, Debra A.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: The carbon to oxygen ratio in a protoplanetary disk can have a dramatic influence on the compositions of any terrestrial planets formed. In regions of high C/O, planets form primarily from carbonates and in regions of low C/O, the ratio of magnesium to silicon determines the types of silicates which dominate the compositions. We present C/O and Mg/Si ratios for 849 F, G, and K dwarfs in the solar neighborhood. We find that the frequency of carbon-rich dwarfs in the solar neighborhood is < 0.13% and that 156 known planet hosts in the sample follow a similar distribution as all of the stars as a whole. The cosmic distribution of Mg/Si for these same stars is broader than the C/O distribution and peaks near 1.0 with $\sim 60$% of systems having $1 \leq$ Mg/Si $< 2$, leading to rocky planet compositions similar to the Earth. This leaves 40% of systems that can have planets that are silicate rich and may have very different compositions than our own.
description: 9 pages, 5 figures, 1 ancillary data table. Accepted for publication to ApJ
Job Prospects and Labour Mobility in China
Creators: name: Wang-Lu, Huaxin
name: Mendoza, Octasiano Miguel Valerio
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Economics (econ.GN)
subject: FOS: Economics and business

description: China's structural changes have brought new challenges to its regional employment structures, entailing labour redistribution. By now Chinese research on migration decisions with a forward-looking stand and on bilateral longitudinal determinants at the prefecture city level is almost non-existent. This paper investigates the effects of sector-based job prospects on individual migration decisions across prefecture boundaries. To this end, we created a proxy variable for job prospects, compiled a unique quasi-panel of 66,427 individuals from 283 cities during 1997--2017, introduced reference-dependence to the random utility maximisation model of migration in a sequential setting, derived empirical specifications with theoretical micro-foundations, and applied various monadic and dyadic fixed effects to address multilateral resistance to migration. Multilevel logit models and two-step system GMM estimation were adopted for the robustness check. Our primary findings are that a 10% increase in the ratio of sector-based job prospects in cities of destination to cities of origin raises the probability of migration by 1.281--2.185 percentage points, and the effects tend to be stronger when the scale of the ratio is larger. Having a family migration network causes an increase of approximately 6 percentage points in migratory probabilities. Further, labour migrants are more likely to be male, unmarried, younger, or more educated. Our results suggest that the ongoing industrial reform in China influences labour mobility between cities, providing important insights for regional policymakers to prevent brain drain and to attract relevant talent.
Constraining the photon mass via Schumann resonances
Creators: name: Malta, P. C.
name: Helayël-Neto, J. A.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Atmospheric and Oceanic Physics (physics.ao-ph)
subject: Geophysics (physics.geo-ph)
subject: FOS: Physical sciences

description: The photon is the paradigm for a massless particle and current experimental tests set severe upper bounds on its mass. Probing such a small mass, or equivalently large Compton wavelength, is challenging at laboratory scales, but planetary or astrophysical phenomena may potentially reach much better sensitivities. In this work we consider the effect of a finite photon mass on Schumann resonances in the Earth-ionosphere cavity, since the TM modes circulating Earth have eigen-frequencies of order $\mathcal{O} (10 \, {\rm Hz})$ that could be sensitive to $m_γ\approx 10^{-14} \, {\rm eV/c}^2$. In particular, we update the limit from Kroll [Phys. Rev. Lett. 27, 340 (1971)], $m_γ\leq 2.4 \times 10^{-13} \, {\rm eV/c}^2$, by considering realistic conductivity profiles for the atmosphere. We find the conservative upper bound $m_γ\leq 2.5 \times 10^{-14} \, {\rm eV/c}^2$, a factor 9.6 more strict than Kroll's earlier projection.
description: 7+2 pages, 3 figures. Matches published version
Generating a Close-to-Reality Synthetic Population of Ghana
Creators: name: Frazier, Tyler J.
name: Alfons, Andreas
Publisher: name: Technische Universität Berlin
Year: 2012
Subjects: subject: 380 Handel, Kommunikation, Verkehr
subject: Ghana
subject: urban dynamics
subject: Greater Accra Urban Simulation System
subject: GAUSS
subject: simulation

description: The purpose of this research is to generate a close-to-reality synthetic human population for use in a geosimulation of urban dynamics. Two commonly accepted approaches to generating synthetic human populations are Iterative Proportional Fitting (IPF) and Resampling with Replacement. While these methods are effective at reproducing one instance of the probability model describing the survey, it is an instance with extremely small variability amongst subgroups and is very unlikely to be the real population. IPF and Resampling with Replacement also rely on pure replication of units from the underlying sample which can increase unrealistic model behavior. In this work we present a sequential logic for estimating variables using multinomial logistic regressions and the conditional probabilities amongst each variable in order to generate combinations which were not represented in the original survey but are likely to occur in the real population. We also present a model based approach to imputing missing observation responses and apply the methodology to the Ghana Living Standard Survey 5 (GLSS5) in order to generate a comprehensive synthetic population for the Republic of Ghana, including such household and person variables as household size, tribal affiliation, educational attainment and annual income, amongst others. The R language and environment for statistical computing was used as well as the packages VIM and simPopulation in developing and executing the code. Contingency coefficients, cumulative distributions, mosaic plots, and box plots are presented for evaluation in order to demonstrate the effectiveness of the new method in its application to Ghana.
Narrow-linewidth cooling of $^{6}$Li atoms using the 2S-3P transition
Creators: name: Chen, Hao-Ze
name: Yao, Xing-Can
name: Wu, Yu-Ping
name: Liu, Xiang-Pei
name: Wang, Xiao-Qiong
name: Chen, Yu-Ao
name: Pan, Jian-Wei
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We report on a narrow-linewidth cooling of $^{6}$Li atoms using the $2S_{1/2}\to 3P_{3/2}$ transition in the ultraviolet (UV) wavelength regime. By combining the traditional red magneto-optical trap (MOT) at 671 nm and the UV MOT at 323 nm, we obtain a cold sample of $1.3\times10^9$ atoms with a temperature of 58 $μ$K. Furthermore, we demonstrate a high efficiency magnetic transport for $^{6}$Li atoms with the help of the UV MOT. Finally, we obtain $8.1\times10^8$ atoms with a temperature of 296 $μ$K at a magnetic gradient of 198 G/cm in the science chamber with a good vacuum environment and large optical access.
Homogeneous Cosmological Models in Weyl's Geometrical Scalar-Tensor Theory
Creators: name: Barros, Adriano
name: Romero, Carlos
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this paper, we consider homogeneous cosmological solutions in the context of the Weyl geometrical scalar-tensor theory. Firstly, we exhibit an anisotropic Kasner type solution taking advantage of some similarities between this theory and the Brans-Dicke theory. Next, we consider an isotropic model with a flat spatial section sourced by matter configurations described by a perfect fluid. In this model, we obtain an analytical solution for the stiff matter case. For other cases, we carry out a complete qualitative analysis theory to investigate the general behaviour of the solutions, presenting some possible scenarios. In this work, we do not consider the presence of the cosmological constant nor do we take any potential of the scalar field into account. Because of this, we do not find any solution describing the acceleration of the universe.
description: 20 pages, 3 figures
File transfer protocol using ISO OSI model & RS 232 interfaces within FMC
Creators: name: Zhao, Wei.
Publisher: name: Monash University
Year: 2022

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Boarding and Alighting Time of Passengers of the Berlin Public Transport System
Creators: name: Neumann, Andreas
name: Kern, Stefan
name: Leich, Gregor
Publisher: name: Technische Universität Berlin
Year: 2014
Subjects: subject: 380 Handel, Kommunikation, Verkehr
subject: Berlin
subject: public transport
subject: transit
subject: boarding time
subject: passenger transfer time

description: The overall transportation speed is a significant factor influencing the attractiveness as well as the profitability of the transit system. If a vehicle needs less time to complete a tour, it can serve more tours and thus more passengers within the same time. Likewise, the passengers benefit from a decreased in-vehicle travel time. In this paper, the factors affecting the passenger transfer time are discussed for the case of Berlin, Germany. Furthermore, the paper presents the results of a survey that focuses (i) on the average time needed for passengers to board and alight a vehicle, (ii) its deviation, and (iii) the impact of the vehicle’s occupancy and number of boarding/alighting passengers. Such data can also be used to model the boarding and alighting process at stops in transport simulations in a more realistic way. For buses and subways, more passengers standing in the door area of a vehicle are found to slow down the boarding and alighting process. The Berlin specific policy to allow the boarding of a bus only at the first door induces a significantly higher boarding time per passenger.
Geometrically exact beam elements and smooth contact schemes for the modeling of fiber-based materials and structures
Creators: name: Meier, Christoph
name: Grill, Maximilian J.
name: Wall, Wolfgang A.
name: Popp, Alexander
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: Recently, the authors have proposed a novel all-angle beam contact (ABC) formulation that combines the advantages of existing point and line contact models in a variationally consistent manner. However, the ABC formulation has so far only been applied in combination with a special torsion-free beam model, which yields a very simple and efficient finite element formulation, but which is restricted to initially straight beams with isotropic cross-sections. In order to abstain from these restrictions, the current work combines the ABC formulation with a geometrically exact Kirchhoff-Love beam element formulation that is capable of treating even the most general cases of slender beam problems in terms of initial geometry and external loads. While the neglect of shear deformation that is inherent to this formulation has been shown to provide considerable numerical advantages in the range of high beam slenderness ratios, alternative shear-deformable beam models are required for examples with thick beams. The current contribution additionally proposes a novel geometrically exact beam element based on the Simo-Reissner theory. Similar to the torsion-free and the Kirchhoff-Love beam elements, also this Simo-Reissner element is based on a C1-continuous Hermite interpolation of the beam centerline, which will allow for smooth contact kinematics. For this Hermitian Simo-Reissner element, a consistent spatial convergence behavior as well as the successful avoidance of membrane and shear locking will be demonstrated numerically. All in all, the combination of the ABC formulation with these different beam element variants (i.e.~the torsion-free element, the Kirchhoff-Love element and the Simo-Reissner element) results in a very flexible and modular simulation framework that allows to choose the optimal element formulation for any given application in terms of accuracy, efficiency and robustness.
Motion equations in a Kerr-Newman-de Sitter spacetime: some methods of integration and application to black holes shadowing in Scilab
Creators: name: Garnier, Arthur
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 83C57, 83C10 (Primary) 85A25, 83F05 (Secondary)

description: In this paper, we recall some basic facts about the Kerr--Newman--(anti) de Sitter (KNdS) spacetime and review several formulations and integration methods for the geodesic equation of a test particle in such a spacetime. In particular, we introduce some basic general symplectic integrators in the Hamiltonian formalism and we re-derive the separated motion equations using Carter's method. After this theoretical background, we explain how to ray-trace a KNdS black hole, equipped with a thin accretion disk, using Scilab. We compare the accuracy and execution time of the previous methods, concluding that the Carter equations is the best one. Then, inspired by Hagihara, we apply Weierstrass' elliptic functions to the non-rotating case, yielding a fairly fast shadowing program for such a spacetime. We provide some illustrations of the code, including a depiction of the effects of the cosmological constant on shadows and accretion disk, as well as a simulation of M87*.
The mitochondrial genome of the endemic and endangered trumpet-nosed bat Musonycteris harrisoni (Chiroptera: Phyllostomidae)
Creators: name: Basaldúa, Sonia
name: Rodriguez-Pilco, Milena
name: Gutiérrez-Guerrero, Yocelyn
name: Ortega, Jorge
name: Baeza, J. Antonio
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Genetics
subject: Molecular Biology
subject: Evolutionary Biology
subject: Ecology
subject: Infectious Diseases
subject: FOS: Health sciences
subject: Computational Biology

description: The trumpet-nosed bat Musonycteris harrisoni (family Phyllostomidae) is endemic to the western Pacific slope of Mexico, and is considered endangered given prolonged and continuous population decline. This study, for the first time, assembled and characterised in detail the mitochondrial genome of this species that is in need of genomic resources. The mitogenome of Musonycteris harrisoni is 16,668 bp in length and encodes 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs), and a relatively long non-coding putative control region (CR) 1229 bp in length. Mitochondrial synteny is identical to that reported before in the family Phyllostomidae. As reported before in all phyllostomids, most mitochondrial genes are encoded on the heavy strand (H-strand), except for nad6 and eight tRNA genes that are encoded on the light strand (L-strand). All the tRNAs exhibit a ‘cloverleaf’ secondary structure, except tRNA Serine-1 that is missing the dihydrouridine (DHU) arm. All 13 mitochondrial PCGs are evolving under purifying selection, with atp8, nad4l and nad6 experiencing relaxed purifying selection in comparison to the other PCGs. Tandem repeats, microsatellites, and hairpin structures are observed in the CR of Musonycteris harrisoni, in agreement with what has been reported before in other cofamilial bats. The CR contains three functional domains: extended termination associated sequence (ETAS) domain, central domain, and conserved sequence block (CSB) domain. The mitochondrial genome sequence herein characterised completely and in detail represents a new genomic resource for M. harrisoni that will further the understanding of genetic diversity in this endangered species.
Stable determination of coefficients in semilinear parabolic system with dynamic boundary conditions
Creators: name: Hassi, E. M. Ait Ben
name: Chorfi, S. E.
name: Maniar, L.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35R30, 93B07 (Primary), 35K58, 93B05 (Secondary)

description: In this work, we study the stable determination of four space-dependent coefficients appearing in a coupled semilinear parabolic system with variable diffusion matrices subject to dynamic boundary conditions which couple intern-boundary phenomena. We prove a Lipschitz stability result for interior and boundary potentials by means of only one observation component, localized in any arbitrary open subset of the physical domain. The proof mainly relies on some new Carleman estimates for dynamic boundary conditions of surface diffusion type.
$L_p$-Theory of Type $1,1$-Operators
Creators: name: Johnsen, Jon
Publisher: name: arXiv
Year: 2016
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35S05 (primary), 47G30 (secondary)

description: This is a continuation of recent work on the general definition of pseudo-differential operators of type $1,1$, in Hörmander's sense. Continuity in $L_p$-Sobolev spaces and Hölder--Zygmund spaces, and more generally in Besov and Lizorkin--Triebel spaces, is proved for positive smoothness, with extension to arbitrary smoothness for operators in the self-adjoint subclass. As a main tool the paradifferential decomposition is used for type $1,1$-operators in combination with the Spectral Support Rule for pseudo-differential operators and pointwise estimates in terms of maximal functions of Peetre--Fefferman--Stein type.
description: 18 pages. The accepted manuscript. (Final version appeared on 14 September 2012 in Mathematische Nachrichten.)
Surprises with Nonrelativistic Naturalness
Creators: name: Horava, Petr
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Superconductivity (cond-mat.supr-con)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We explore the landscape of technical naturalness for nonrelativistic systems, finding surprises which challenge and enrich our relativistic intuition already in the simplest case of a single scalar field. While the immediate applications are expected in condensed matter and perhaps in cosmology, the study is motivated by the leading puzzles of fundamental physics involving gravity: The cosmological constant problem and the Higgs mass hierarchy problem.
description: 15 pages, a few figures
Robots with Different Embodiments Can Express and Influence Carefulness in Object Manipulation
Creators: name: Lastrico, Linda
name: Garello, Luca
name: Rea, Francesco
name: Noceti, Nicoletta
name: Mastrogiovanni, Fulvio
name: Sciutti, Alessandra
name: Carfi, Alessandro
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Humans have an extraordinary ability to communicate and read the properties of objects by simply watching them being carried by someone else. This level of communicative skills and interpretation, available to humans, is essential for collaborative robots if they are to interact naturally and effectively. For example, suppose a robot is handing over a fragile object. In that case, the human who receives it should be informed of its fragility in advance, through an immediate and implicit message, i.e., by the direct modulation of the robot's action. This work investigates the perception of object manipulations performed with a communicative intent by two robots with different embodiments (an iCub humanoid robot and a Baxter robot). We designed the robots' movements to communicate carefulness or not during the transportation of objects. We found that not only this feature is correctly perceived by human observers, but it can elicit as well a form of motor adaptation in subsequent human object manipulations. In addition, we get an insight into which motion features may induce to manipulate an object more or less carefully.
description: Proceedings of the IEEE International Conference on Development and Learning (ICDL 2022) - preprint version, published version available at https://ieeexplore.ieee.org/document/9962196
Comment on "Fermion production in a magnetic field in a de Sitter universe"
Creators: name: Nicolaevici, Nistor
name: Farkas, Attila
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We point out that the transition probabilities used in a recent perturbative calculation of pair creation in an external magnetic field in the expanding de Sitter space with the $in$ and $out$ fermion states defined by the Bunch-Davies modes [C. Crucean et al., Phys. Rev. D 73 044019 (20016)] are gauge dependent quantities. We examine the gauge variations of these amplitudes assuming a decoupling of the interaction at infinite times, which allows to conclude that the source of the problem lies in the nonoscillatory behavior of the fermion current in the infinite future.
description: 13 pages; no figures; to appear in PRD
Towards Fast and Scalable Private Inference
Creators: name: Mo, Jianqiao
name: Garimella, Karthik
name: Neda, Negar
name: Ebel, Austin
name: Reagen, Brandon
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cryptography and Security (cs.CR)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Privacy and security have rapidly emerged as first order design constraints. Users now demand more protection over who can see their data (confidentiality) as well as how it is used (control). Here, existing cryptographic techniques for security fall short: they secure data when stored or communicated but must decrypt it for computation. Fortunately, a new paradigm of computing exists, which we refer to as privacy-preserving computation (PPC). Emerging PPC technologies can be leveraged for secure outsourced computation or to enable two parties to compute without revealing either users' secret data. Despite their phenomenal potential to revolutionize user protection in the digital age, the realization has been limited due to exorbitant computational, communication, and storage overheads. This paper reviews recent efforts on addressing various PPC overheads using private inference (PI) in neural network as a motivating application. First, the problem and various technologies, including homomorphic encryption (HE), secret sharing (SS), garbled circuits (GCs), and oblivious transfer (OT), are introduced. Next, a characterization of their overheads when used to implement PI is covered. The characterization motivates the need for both GCs and HE accelerators. Then two solutions are presented: HAAC for accelerating GCs and RPU for accelerating HE. To conclude, results and effects are shown with a discussion on what future work is needed to overcome the remaining overheads of PI.
description: Appear in the 20th ACM International Conference on Computing Frontiers
Stability of twisted states in the continuum Kuramoto model
Creators: name: Medvedev, Georgi S.
name: Wright, J. Douglas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Pattern Formation and Solitons (nlin.PS)
subject: Analysis of PDEs (math.AP)
subject: FOS: Physical sciences
subject: FOS: Mathematics

description: We study a nonlocal diffusion equation approximating the dynamics of coupled phase oscillators on large graphs. Under appropriate assumptions, the model has a family of steady state solutions called twisted states. We prove a sufficient condition for stability of twisted states with respect to perturbations in the Sobolev and BV spaces. As an application, we study stability of twisted states in the Kuramoto model on small-world graphs.
Information Security and Knowledge Management: Solutions Through Analogies?
Creators: name: Glaser, Timo
name: Pallas, Frank
Publisher: name: Technische Universität Berlin
Year: 2007
Subjects: subject: 004 Datenverarbeitung; Informatik
subject: information security
subject: information security management
subject: knowledge management
subject: economics

description: Information Security Management and Knowledge Management show a couple of intriguing similarities. This paper identifies some of these similarities and highlights abstract problems arising from them in both areas. Those analogies motivate to look for possibilities to transfer solutions from one area to the other.
A Multiple Kernel Learning Approach for Human Behavioral Task Classification using STN-LFP Signal
Creators: name: Golshan, Hosein M.
name: Hebb, Adam O.
name: Hanrahan, Sara J.
name: Nedrud, Joshua
name: Mahoor, Mohammad H.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: Deep Brain Stimulation (DBS) has gained increasing attention as an effective method to mitigate Parkinsons disease (PD) disorders. Existing DBS systems are open-loop such that the system parameters are not adjusted automatically based on patients behavior. Classification of human behavior is an important step in the design of the next generation of DBS systems that are closed-loop. This paper presents a classification approach to recognize such behavioral tasks using the subthalamic nucleus (STN) Local Field Potential (LFP) signals. In our approach, we use the time-frequency representation (spectrogram) of the raw LFP signals recorded from left and right STNs as the feature vectors. Then these features are combined together via Support Vector Machines (SVM) with Multiple Kernel Learning (MKL) formulation. The MKL-based classification method is utilized to classify different tasks: button press, mouth movement, speech, and arm movement. Our experiments show that the lp-norm MKL significantly outperforms single kernel SVM-based classifiers in classifying behavioral tasks of five subjects even using signals acquired with a low sampling rate of 10 Hz. This leads to a lower computational cost.
description: 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Scociety
Predictive Entropy Search for Multi-objective Bayesian Optimization with Constraints
Creators: name: Garrido-Merchán, Eduardo C.
name: Hernández-Lobato, Daniel
Publisher: name: arXiv
Year: 2016
Subjects: subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: This work presents PESMOC, Predictive Entropy Search for Multi-objective Bayesian Optimization with Constraints, an information-based strategy for the simultaneous optimization of multiple expensive-to-evaluate black-box functions under the presence of several constraints. PESMOC can hence be used to solve a wide range of optimization problems. Iteratively, PESMOC chooses an input location on which to evaluate the objective functions and the constraints so as to maximally reduce the entropy of the Pareto set of the corresponding optimization problem. The constraints considered in PESMOC are assumed to have similar properties to those of the objective functions in typical Bayesian optimization problems. That is, they do not have a known expression (which prevents gradient computation), their evaluation is considered to be very expensive, and the resulting observations may be corrupted by noise. These constraints arise in a plethora of expensive black-box optimization problems. We carry out synthetic experiments to illustrate the effectiveness of PESMOC, where we sample both the objectives and the constraints from a Gaussian process prior. The results obtained show that PESMOC is able to provide better recommendations with a smaller number of evaluations than a strategy based on random search.
description: 6 pages 2 figures
Fast forward to the classical adiabatic invariant
Creators: name: Jarzynski, Christopher
name: Deffner, Sebastian
name: Patra, Ayoti
name: Subaşı, Yiğit
Publisher: name: arXiv
Year: 2016
Subjects: subject: Classical Physics (physics.class-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We show how the classical action, an adiabatic invariant, can be preserved under non-adiabatic conditions. Specifically, for a time-dependent Hamiltonian $H = p^2/2m + U(q,t)$ in one degree of freedom, and for an arbitrary choice of action $I_0$, we construct a "fast-forward" potential energy function $V_{\rm FF}(q,t)$ that, when added to $H$, guides all trajectories with initial action $I_0$ to end with the same value of action. We use this result to construct a local dynamical invariant $J(q,p,t)$ whose value remains constant along these trajectories. We illustrate our results with numerical simulations. Finally, we sketch how our classical results may be used to design approximate quantum shortcuts to adiabaticity.
description: 5 pages
Multi-Axis Control of a Qubit in the Presence of Unknown Non-Markovian Quantum Noise
Creators: name: Youssry, Akram
name: Nurdin, Hendra I.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Systems and Control (eess.SY)
subject: FOS: Physical sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: In this paper, we consider the problem of open-loop control of a qubit that is coupled to an unknown fully quantum non-Markovian noise (either bosonic or fermionic). A graybox model that is empirically obtained from measurement data is employed to approximately represent the unknown quantum noise. The estimated model is then used to calculate the open-loop control pulses under constraints on the pulse amplitude and timing. For the control pulse optimization, we explore the use of gradient descent and genetic optimization methods. We consider the effect of finite sampling on estimating expectation values of observables and show results for single- and multi-axis control of a qubit.
Role of microscopic degrees of freedom in mechanical response of bicrystal nanopillars
Creators: name: Mishra, Avanish
name: Dang, Khanh
name: Kober, Edward M.
name: Fensin, Saryu J.
name: Mathew, Nithin
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biophysics
subject: Physical Sciences not elsewhere classified
subject: Cell Biology
subject: Molecular Biology
subject: Physiology
subject: FOS: Biological sciences
subject: Ecology
subject: Marine Biology
subject: Hematology
subject: Plant Biology
subject: Computational Biology

description: This study investigated the high-strain rate deformation of bicrystal Cu nanopillars, using atomistic simulations. Nanopillars with minimum grain boundary energy were deformed to investigate the role of macroscopic degrees of freedom, finding that geometric parameters (Schmid factor) influence the stress–strain response. The deformation of metastable grain boundaries (GBs) revealed that in addition to geometric parameters, the response was also governed by the local atomic arrangement at the boundary, dictating the dislocation-GB interactions. These findings shed light on the response of nanopillars as a function of GBs and show the importance of both macroscopic and microscopic degrees of freedom on the mechanical response. Metastable states, an often ignored aspect of GB structure, is shown to have a strong influence on dislocation-GB interactions; shedding new light on mechanical response of realistic GBs.
Patella fractures ORIF - To evert or not to evert?
Creators: name: D. Santos
name: A. Gavagnin
name: A. Fernández
Publisher: name: Zenodo
Year: 2020
Subjects: direct visualization
patella eversion
patella fracture
patella comminution
cannulated screws
tension band
cerclage
joint reduction
functional outcome
residual pain
ICUC Score
interactive 3D color model
parapatellar approach

description: Comments from: D. Hoentzsch, R. Babst, F. Beeres, B. Link Perfect reduction of the anterior cortex may or may not lead to perfect joint surface reduction. Joint reduction under visual control has been proposed.
Machine Learning-Assisted Manipulation and Readout of Molecular Spin Qubits
Creators: name: Bonizzoni, Claudio
name: Tincani, Mirco
name: Santanni, Fabio
name: Affronte, Marco
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Machine Learning finds application in the quantum control and readout of qubits. In this work we apply Artificial Neural Networks to assist the manipulation and the readout of a prototypical molecular spin qubit - an Oxovanadium(IV) moiety - in two experiments designed to test the amplitude and the phase recognition, respectively. We first successfully use an artificial network to analyze the output of a Storage/Retrieval protocol with four input pulses to recognize the echo positions and, with further post selection on the results, to infer the initial input pulse sequence. We then apply an Artificial Neural Network to ascertain the phase of the experimentally measured Hahn echo, showing that it is possible to correctly detect its phase and to recognize additional single-pulse phase shifts added during manipulation.
description: 10 pages, 5 figures
Efficiency of gas cooling and accretion at the disc-corona interface
Creators: name: Armillotta, L.
name: Fraternali, F.
name: Marinacci, F.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: In star-forming galaxies, stellar feedback can have a dual effect on the circumgalactic medium both suppressing and stimulating gas accretion. The trigger of gas accretion can be caused by disc material ejected into the halo in the form of fountain clouds and by its interaction with the surrounding hot corona. Indeed, at the disc-corona interface, the mixing between the cold/metal-rich disc gas (T ~ 10^6 K) can dramatically reduce the cooling time of a portion of the corona and produce its condensation and accretion. We studied the interaction between fountain clouds and corona in different galactic environments through parsec-scale hydrodynamical simulations, including the presence of thermal conduction, a key mechanism that influences gas condensation. Our simulations showed that the coronal gas condensation strongly depends on the galactic environment, in particular it is less efficient for increasing virial temperature/mass of the haloes where galaxies reside and it is fully ineffective for objects with virial masses larger than 10^13 Msun. This result implies that the coronal gas cools down quickly in haloes with low-intermediate virial mass (Mvir
description: 14 pages, 8 figures, accepted for publication in MNRAS