cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Quantum Langevin equations for optomechanical systems
Creators: name: Barchielli, Alberto
name: Vacchini, Bassano
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We provide a fully quantum description of a mechanical oscillator in the presence of thermal environmental noise by means of a quantum Langevin formulation based on quantum stochastic calculus. The system dynamics is determined by symmetry requirements and equipartition at equilibrium, while the environment is described by quantum Bose fields in a suitable non-Fock representation which allows for the introduction of temperature. A generic spectral density of the environment can be described by introducing its state trough a suitable P-representation. Including interaction of the mechanical oscillator with a cavity mode via radiation pressure we obtain a description of a simple optomechanical system in which, besides the Langevin equations for the system, one has the exact input-output relations for the quantum noises. The whole theory is valid at arbitrarily low temperature. This allows the exact calculation of the stationary value of the mean energy of the mechanical oscillator, as well as both homodyne and heterodyne spectra. The present analysis allows in particular to study possible cooling scenarios and to obtain the exact connection between observed spectra and fluctuation spectra of the position of the mechanical oscillator.
description: 37 pages, 2 figures. Major revisions; new references
Linear Response for pseudo-Hermitian Hamiltonian Systems: Application to PT-Symmetric Qubits
Creators: name: Tetling, L.
name: Fistul, M. V.
name: Eremin, Ilya M.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Motivated by the recent advances in modelling the pseudo-Hermitian Hamiltonian (pHH) systems using superconducting qubits we analyze their quantum dynamics subject to a small time-dependent perturbation. In particular, We develop the linear response theory formulation suitable for application to various pHH systems and compare it to the ones available in the literature. We derive analytical expressions for the generalized temporal quantum-mechanical correlation function $C(t)$ and the time-dependent dynamic susceptibility $χ(t) \propto \text{Im} ~C(t)$. We apply our results to two \textit{PT}-symmetric non-Hermitian quantum systems: a single qubit and two unbiased/biased qubits coupled by the exchange interaction. For both systems we obtain the eigenvalues and eigenfunctions of the Hamiltonian, identify \textit{PT}-symmetry unbroken and broken quantum phases and quantum phase transitions between them. The temporal oscillations of the dynamic susceptibility of the qubits polarization ($z$-projection of the total spin), $χ(t)$, relate to {\it ac} induced transitions between different eigenstates and we analyze the dependencies of the oscillations frequency and the amplitude on the gain/loss parameter $γ$ and the interaction strength $g$. Studying the time dependence of $χ(t)$ we observe different types of oscillations, i.e. undamped, heavily damped and amplified ones, related to the transitions between eigenstates with broken (unbroken) $PT$-symmetry. These predictions can be verified in the microwave transmission experiments allowing controlled simulation of the pHH systems.
description: 11 pages, 6 figures, published version
SEMI-BLOCH PERIODIC FUNCTIONS, SEMI-ANTI-PERIODIC FUNCTIONS AND APPLICATIONS
Creators: name: B. Chaouchi
name: M. Kostic
name: S. Pilipovic
name: D. Velinov
Publisher: name: Челябинский физико-математический журнал
Year: 2020
Subjects: semi-Bloch k-periodic functions
semi-anti-periodic functions
integro-differential equations.

description: We introduce the notions of semi-Bloch periodic functions and semi-anti-periodic functions. Stepanov semi-Bloch periodic functions and Stepanov semi-anti-periodic functions are considered, as well. We analyze the invariance of introduced classes under actions of convolution products and briefly explain how one can use the obtained results in the qualitative analysis of solutions of abstract inhomogeneous integro-differential equations.
Multi-level Operation of FeFETs Memristors: the Crucial Role of Three Dimensional Effects
Creators: name: Lizzit, Daniel
name: Bernardi, Thomas
name: Esseni, David
Publisher: name: arXiv
Year: 2023
Subjects: subject: Emerging Technologies (cs.ET)
subject: FOS: Computer and information sciences

description: This paper investigates and compares through a comprehensive TCAD analysis 2D and 3D simulations for ferroelectric based FETs. We provide clear evidence that the multiple read conductance values experimentally observed in FeFETs stem from source to drain percolation current paths, which are governed by the polarization patterns in the ferroelectric domains. Such a physical picture makes 3D simulations indispensable to capture even the qualitative features of the device behaviour, not to mention the quantitative aspects.
description: Proceeding of the ESSDERC2022 conference
Highly excited and exotic fully-strange tetraquark states
Creators: name: Dong, Rui-Rui
name: Su, Niu
name: Chen, Hua-Xing
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: Some hadrons have the exotic quantum numbers that the traditional $\bar q q$ mesons and $qqq$ baryons can not reach, such as $J^{PC} = 0^{--}/0^{+-}/1^{-+}/2^{+-}/3^{-+}/4^{+-}$, etc. We investigate for the first time the exotic quantum number $J^{PC}=4^{+-}$, and study the fully-strange tetraquark states with such an exotic quantum number. We systematically construct all the diquark-antidiquark interpolating currents, and apply the method of QCD sum rules to calculate both the diagonal and off-diagonal correlation functions. The obtained results are used to construct three mixing currents that are nearly non-correlated, and we use one of them to extract the mass of the lowest-lying state to be $2.85^{+0.19}_{-0.22}$ GeV. We apply the Fierz rearrangement to transform this mixing current to be the combination of three meson-meson currents, and the obtained Fierz identity suggests that this state dominantly decays into the $P$-wave $ϕ(1020) f_2^\prime(1525)$ channel. This fully-strange tetraquark state of $J^{PC}=4^{+-}$ is a purely exotic hadron to be potentially observed in future particle experiments.
description: 8 pages, 7 figures, 1 table, revised version to be published in EPJC
NLRs and the dangers of pollution and aging
Creators: name: Ting, J.P.-Y.
name: Willingham, S.B.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2008

description: Inflammatory interleukin 1β production after silica and alum crystal or β-amyloid uptake occurs via a process involving lysosomal destabilization and release of cathepsin B that activates the NALP3 inflammasome.
Collective dynamics in two populations of noisy oscillators with asymmetric interactions
Creators: name: Sonnenschein, Bernard
name: Peron, Thomas K. DM.
name: Rodrigues, Francisco A.
name: Kurths, Jürgen
name: Schimansky-Geier, Lutz
Publisher: name: arXiv
Year: 2015
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study two intertwined globally coupled networks of noisy Kuramoto phase oscillators that have the same natural frequency, but differ in their perception of the mean field and their contribution to it. Such a give-and-take mechanism is given by asymmetric in- and out-coupling strengths which can be both positive and negative. We uncover in this minimal network of networks intriguing patterns of discordance, where the ensemble splits into two clusters separated by a constant phase lag. If it differs from $π$, then traveling wave solutions emerge. We observe a second route to traveling waves via traditional one-cluster states. Bistability is found between the various collective states. Analytical results and bifurcation diagrams are derived with a reduced system.
description: 8 pages, 5 figures, published in Phys. Rev. E
Optimizing site-specific specimen preparation for Atom Probe Tomography by using hydrogen for visualizing radiation-induced damage
Creators: name: Saksena, Aparna
name: Sun, Binhan
name: Dong, Xizhen
name: Khanchandani, Heena
name: Ponge, Dirk
name: Gault, Baptiste
Publisher: name: arXiv
Year: 2023
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Atom probe tomography (APT) is extensively used to measure the local chemistry of materials. Site-specific preparation via a focused ion beam (FIB) is routinely implemented to fabricate needle-shaped specimens with an end radius in the range of 50 nm. This preparation route is sometimes supplemented by transmission Kikuchi diffraction (TKD) to facilitate the positioning of a region of interest sufficiently close to the apex. Irradiating the specimen with energetic electrons and ions can lead to the generation of vacancies and even amorphization of the specimen. These extrinsically created vacancies become crucial for probing the hydrogen or deuterium distribution since they act as a strong trap. Here, we investigated the feasibility of site-specific preparation of a two-phase medium-Mn steel containing austenite (fcc) and ferrite (bcc). Following gaseous charging of APT specimens in deuterium (D2), clusters enriched by up to 35 at.% D, are imaged after Pt deposition, conventional Ga-FIB preparation, and TKD conducted separately. These D-rich clusters are assumed to arise from the agglomeration of vacancies acting as strong traps. By systematically eliminating these preparation-induced damages, we finally introduce a workflow allowing for studying intrinsic traps for H/D inherent to the material.
Partial lifting of degeneracy in the $J_1-J_2-J_3$ Ising antiferromagnet on the kagome lattice
Creators: name: Colbois, Jeanne
name: Vanhecke, Bram
name: Vanderstraeten, Laurens
name: Smerald, Andrew
name: Verstraete, Frank
name: Mila, Frédéric
Publisher: name: arXiv
Year: 2022
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Motivated by dipolar-coupled artificial spin systems, we present a theoretical study of the classical $J_1-J_2-J_3$ Ising antiferromagnet on the kagome lattice. We establish the ground-state phase diagram of this model for $J_1 > |J_2|, |J_3|$ based on exact results for the ground-state energies. When all the couplings are antiferromagnetic, the model has three macroscopically degenerate ground-state phases, and using tensor networks, we can calculate the entropies of these phases and of their boundaries very accurately. In two cases, the entropy appears to be a fraction of that of the triangular lattice Ising antiferromagnet, and we provide analytical arguments to support this observation. We also notice that, surprisingly enough, the dipolar ground state is not a ground state of the truncated model, but of the model with smaller $J_3$ interactions, an indication of a very strong competition between low-energy states in this model.
description: Accepted version for PRB; 23 pages (16 main text), 20 figures
Entanglement wedge cross section inequalities in AdS/BCFT
Creators: name: Li, Pan
name: Ling, Yi
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The entanglement wedge cross section in holographic picture provides a geometrical description of the entanglement for mixed states. In this paper we study the inequalities for the entanglement wedge cross section in AdS/BCFT duality. In the presence of the boundary in conformal field theory (CFT), the dual entanglement wedge cross section exhibits abundant phase structures since the extremal surface may end on the brane. We present a universal treatment which is applicable for all the possible phases such that the inequalities for the entanglement wedge cross section can be proved in an algebraic manner rather than a diagrammatic manner. We show that the entanglement wedge cross section in AdS/BCFT satisfies the same inequalities as in AdS/CFT.
Comparison of Aβb-/-, H2-DM-, and CIITA-/- in second-set skin allograft rejection
Creators: name: De Serres, S.
name: Meyer, A.A.
name: Ting, J.P.-Y.
name: Felix, N.J.
Publisher: name: Elsevier
Year: 2002

description: Background. Responses against donor MHC antigens are the major contributor to allograft rejection. Currently, it is unclear whether both direct and indirect recognition pathways are necessary and/or sufficient for allograft rejection. Previously, we found donor MHC class II and H2-DM to have dramatic effects on cardiac allograft survival. Methods. Here, we used H2-DM- mice, which express CLIP-MHC class II complexes, and CIITA-/- mice, which lack all class II proteins, to examine the role of direct and indirect recognition on skin allograft rejection. Recipients were primed with donor cultured keratinocytes and later tested for accelerated memory response by challenge with full-thickness tail skin grafts. Results. As previously reported, Aβb-/- grafts survived longer than wild-type grafts, while H2-DM- grafts were rejected as rapidly as wild-type grafts. Skin grafts deficient for both β2m and H2-DM survived longer than grafts lacking only H2-DM, but not as long as Aβb-/- grafts. Additionally, CIITA-/- grafts survived as long as Aβb-/- grafts. Conclusions. The delayed rejection of Aβb-/- compared to H2-DM- suggests that indirect recognition of surface-expressed donor MHC class II is sufficient to mediate rapid skin allograft rejection. The equivalent survival of CIITA-/- and Aβb-/- grafts suggests that indirect presentation of donor class II molecules (Aα or Eβ) present in Aβb-/- but not CIITA-/- mice does not contribute to graft rejection. These results reveal a modest role for surface-expressed donor class II in primed keratinocyte rejection, but also reveal a dramatic contrast to the cardiac allograft system and indicate tissue/organ-specific mechanisms of rejection.
Differential selectivity of CIITA promoter activation by IFN-γ and IRF- 1 in astrocytes and macrophages: CIITA promoter activation is not affected by TNF-α
Creators: name: Wang, Y.
name: Ting, J.P.-Y.
name: Piskurich, J.F.
name: Hellendall, R.P.
name: Nikcevich, K.M.
Publisher: name: Elsevier
Year: 1999

description: During demyelinating disease of the central nervous system (CNS), locally elevated cytokine levels may induce upregulation of MHC class II molecules on otherwise low expressing or negative cell types such as microglia and astrocytes, since IFN-γ has been shown to induce MHC class II expression on these cell types in vitro. While many transcription factors are involved with MHC class II expression, only the class II transactivator (CIITA) is tightly coordinated with IFN-γ-inducibility. Control of CIITA gene expression is complex, involving four distinct promoters, two of which (promoters III and IV) are IFN-γ-inducible in certain cell types. Here we demonstrate that IFN-γ treatment of rat astrocytes induces only CIITA promoter IV activity in contrast to the murine macrophage cell line RAW 264.7 that uses both IFN-γ-inducible promoters. In contrast to previously published reports, promoter IV activation is completely dependent upon an intact interferon regulatory factor-1 (IRF-1) but not STAT1 binding site using promoter constructs specifically mutated at these positions. Importantly, while TNF-α is able to synergize with IFN-γ to increase astrocyte MHC class II expression in vitro, we show that treatment of rat astrocytes with TNF-α has no effect on CIITA promoter activity. These data demonstrate that TNF-α augments MHC class II expression through a mechanism downstream or independent of CIITA induction.
Paclitaxel (Taxol)-induced gene expression and cell death are both mediated by the activation of c-Jun NH2-terminal kinase (JNK/SAPK)
Creators: name: Li, G.
name: Lee, L.-F.
name: Templeton, D.J.
name: Ting, J.P.-Y.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 1998

description: Paclitaxel (Taxol) is a novel anti-cancer drug that has shown efficacy toward several malignant tumors, particularly ovarian tumors. We reported previously that paclitaxel can induce interleukin (IL)-8 promoter activation in subgroups of ovarian cancer through the activation of both AP-1 and nuclear factor κB. Further analysis of paclitaxel analogs indicates that the degree of IL-8 induction by analysis correlates with the extent of cell death; however, IL-8 itself is not the cause of cell death. This suggests that pathways that lead to IL-8 and cell death may overlap, although IL-8 per se does not kill tumor cells. To decipher the upstream signals for paclitaxel-induced transcriptional activation and cell death, we studied the involvement of protein kinases that lead to the activation of AP-1, specifically the c-Jun NH2-terminal kinase (JNK1), p38, and the extracellular signal-regulated kinase 1 (ERK1). The role of IκB in paclitaxel-induced cell death was also analyzed. Paclitaxel activated JNK, and to a lesser degree p38, but not ERK1. Paclitaxel-induced IL-8 promoter activation was inhibited by dominant-inhibitory mutants of JNK, p38, and the super-repressor form of IκBα, but not by dominant-inhibitory forms of ERK1. Dominant-inhibitory mutants of JNK1 also greatly reduced paclitaxel-induced cell death, and the kinetics of JNK induction was closely followed by DNA fragmentation. These results indicate (i) that paclitaxel activates the JNK signaling pathway and (ii) that JNK activation is a common point of paclitaxel-induced gene induction and cell death.
Automatic Music Playlist Generation via Simulation-based Reinforcement Learning
Creators: name: Tomasi, Federico
name: Cauteruccio, Joseph
name: Kanoria, Surya
name: Ciosek, Kamil
name: Rinaldi, Matteo
name: Dai, Zhenwen
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Personalization of playlists is a common feature in music streaming services, but conventional techniques, such as collaborative filtering, rely on explicit assumptions regarding content quality to learn how to make recommendations. Such assumptions often result in misalignment between offline model objectives and online user satisfaction metrics. In this paper, we present a reinforcement learning framework that solves for such limitations by directly optimizing for user satisfaction metrics via the use of a simulated playlist-generation environment. Using this simulator we develop and train a modified Deep Q-Network, the action head DQN (AH-DQN), in a manner that addresses the challenges imposed by the large state and action space of our RL formulation. The resulting policy is capable of making recommendations from large and dynamic sets of candidate items with the expectation of maximizing consumption metrics. We analyze and evaluate agents offline via simulations that use environment models trained on both public and proprietary streaming datasets. We show how these agents lead to better user-satisfaction metrics compared to baseline methods during online A/B tests. Finally, we demonstrate that performance assessments produced from our simulator are strongly correlated with observed online metric results.
description: 10 pages. KDD 23
Spatial coherence and stability in a disordered organic polariton condensate
Creators: name: Daskalakis, Konstantinos S.
name: Maier, Stefan A.
name: Kéna-Cohen, Stéphane
Publisher: name: arXiv
Year: 2015
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Although only a handful of organic materials have shown polariton condensation, their study is rapidly becoming more accessible. The spontaneous appearance of long-range spatial coherence is often recognized as a defining feature of such condensates. In this work, we study the emergence of spatial coherence in an organic microcavity and demonstrate a number of unique features stemming from the peculiarities of this material set. Despite its disordered nature, we find that correlations extend over the entire spot size and we measure $g^{(1)}(r,r')$ values of nearly unity at short distances and of 50% for points separated by nearly 10 $μ$m. We show that for large spots, strong shot to shot fluctuations emerge as varying phase gradients and defects, including the spontaneous formation of vortices. These are consistent with the presence of modulation instabilities. Furthermore, we find that measurements with flat-top spots are significantly influenced by disorder and can, in some cases, lead to the formation of mutually incoherent localized condensates.
description: Revised version
PaperToPlace: Transforming Instruction Documents into Spatialized and Context-Aware Mixed Reality Experiences
Creators: name: Chen, Chen
name: Nguyen, Cuong
name: Hoffswell, Jane
name: Healey, Jennifer
name: Bui, Trung
name: Weibel, Nadir
Publisher: name: arXiv
Year: 2023
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences
subject: H.4.m; H.5.2; I.7.m

description: While paper instructions are one of the mainstream medium for sharing knowledge, consuming such instructions and translating them into activities are inefficient due to the lack of connectivity with physical environment. We present PaperToPlace, a novel workflow comprising an authoring pipeline, which allows the authors to rapidly transform and spatialize existing paper instructions into MR experience, and a consumption pipeline, which computationally place each instruction step at an optimal location that is easy to read and do not occlude key interaction areas. Our evaluations of the authoring pipeline with 12 participants demonstrated the usability of our workflow and the effectiveness of using a machine learning based approach to help extracting the spatial locations associated with each steps. A second within-subject study with another 12 participants demonstrates the merits of our consumption pipeline by reducing efforts of context switching, delivering the segmented instruction steps and offering the hands-free affordances.
description: 21 pages, 23 figures, Proceedings of the 36th Annual ACM Symposium on User Interface Software and Technology (UIST '23), San Francisco, CA, USA
Stärkung der beruflichen Lehrkräftebildung an der Leibniz Universität Hannover durch die phasen- und fachübergreifende „Plattform Lehramt an berufsbildenden Schulen“ (plabs)
Creators: name: Otten, Kathrin
name: Schäfers, Johannes
name: Gillen, Julia
name: Bach, Alexandra
name: Mackel, Sina
name: Becker, Matthias
Publisher: name: wbv Media
Year: 2024
Subjects: subject: vocational teacher education | digitalisation | coherence | learning platform | studyability
classificationCode: 3
subject: Social Sciences::370: Education
classificationCode: 0
subject: Computer Science, Information and General Works::004: Computer Sciences

description: Zur Verbesserung der Studierbarkeit und Qualitätssteigerung der Studiengänge für Lehrkräfte an berufsbildenden Schulen werden elaborierte Digitalisierungskonzepte als zukunftsweisend eingeschätzt (vgl. Pengel et al. 2017). Neben dem bekannten Paradigma der Entkopplung von Zeit- und Raumabhängigkeit durch online-basierte Distanz-Lernphasen wird in diesem Beitrag dargelegt, wie Lernangebote aus unterschiedlichen Studienbereichen im beruflichen Lehramtsstudium durch ausgewählte (digitale) Angebots- und Arbeitsstrukturen auf einer gemeinsamen Lern-, Arbeits- und Netzwerkumgebung, der Plattform plabs zusammengeführt werden, um damit die Kohärenz der Lernangebote im Lehramtsstudium und die fächerübergreifende Zusammenarbeit der Lehrenden und Studierenden zu fördern.
description: In order to improve the studyability and quality of the study programmes for teachers at vocational schools, elaborated digitisation concepts are considered forward-looking (cf. Pengel et al. 2017). In addition to the well-known paradigm of decoupling time and space dependency through online-based distance learning phases, this article explains how learning opportunities from different fields of study in vocational teacher training are brought together through selected (digital) offer and work structures on a common learning, work and network environment, the platform plabs, in order to promote the coherence of learning opportunities in teacher training and the interdisciplinary cooperation of teachers and students.
Microglial/macrophage accumulation during cuprizone-induced demyelination in C57BL/6 mice
Creators: name: Matsushima, G.K.
name: Hiremath, M.M.
name: Knapp, G.W.
name: Saito, Y.
name: Suzuki, K.
name: Ting, J.P.-Y.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 1998

description: To study microglial/macrophage infiltration, a cuprizone-induced model for demyelination in C57BL/6 mice was established. Cuprizone is known to cause demyelination in Swiss mice, however, cuprizone-induced demyelination in C57BL/6 mice has not been previously described. Induction of demyelination in C57BL/6 mice enables examination of the function of microglia/macrophage through comparative analyses of syngeneic mice with various targeted genetic mutations. In this report, cuprizone-induced demyelination is easily inducible, localized, and predictable. Concurrent with the initiation of demyelination, we noted microglial/macrophage accumulation and changes in astrocyte morphology. Astrogliosis promptly followed microglia/macrophage recruitment. These observations suggested that microglia/macrophage actively contribute to the demyelination process.
Training and Predicting Visual Error for Real-Time Applications
Creators: name: Cardoso, João Libório
name: Kerbl, Bernhard
name: Yang, Lei
name: Uralsky, Yury
name: Wimmer, Michael
Publisher: name: arXiv
Year: 2023
Subjects: subject: Graphics (cs.GR)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences
subject: I.3.3; I.2.10; I.2.6

description: Visual error metrics play a fundamental role in the quantification of perceived image similarity. Most recently, use cases for them in real-time applications have emerged, such as content-adaptive shading and shading reuse to increase performance and improve efficiency. A wide range of different metrics has been established, with the most sophisticated being capable of capturing the perceptual characteristics of the human visual system. However, their complexity, computational expense, and reliance on reference images to compare against prevent their generalized use in real-time, restricting such applications to using only the simplest available metrics. In this work, we explore the abilities of convolutional neural networks to predict a variety of visual metrics without requiring either reference or rendered images. Specifically, we train and deploy a neural network to estimate the visual error resulting from reusing shading or using reduced shading rates. The resulting models account for 70%-90% of the variance while achieving up to an order of magnitude faster computation times. Our solution combines image-space information that is readily available in most state-of-the-art deferred shading pipelines with reprojection from previous frames to enable an adequate estimate of visual errors, even in previously unseen regions. We describe a suitable convolutional network architecture and considerations for data preparation for training. We demonstrate the capability of our network to predict complex error metrics at interactive rates in a real-time application that implements content-adaptive shading in a deferred pipeline. Depending on the portion of unseen image regions, our approach can achieve up to $2\times$ performance compared to state-of-the-art methods.
description: Published at Proceedings of the ACM in Computer Graphics and Interactive Techniques. 14 Pages, 16 Figures, 3 Tables. For paper website and higher quality figures, see https://jaliborc.github.io/rt-percept/
Palatini $R^2$ Quintessential Inflation
Creators: name: Dimopoulos, Konstantinos
name: Karam, Alexandros
name: López, Samuel Sánchez
name: Tomberg, Eemeli
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We construct a model of quintessential inflation in Palatini $R^2$ gravity employing a scalar field with a simple exponential potential and coupled to gravity with a running non-minimal coupling. At early times, the field acts as the inflaton, while later on it becomes the current dark energy. Combining the scalar sector with an ideal fluid, we study the cosmological evolution of the model from inflation all the way to dark energy domination. We interpret the results in the Einstein frame, where a coupling emerges between the fluid and the field, feeding energy from the former to the latter during the matter-dominated era. We perform a numerical scan over the parameter space and find points that align with observations for both the inflationary CMB data and the late-time behaviour. The final dark energy density emerges from an interplay between the model parameters, without requiring the extreme fine-tuning of the cosmological constant in $Λ$CDM.
description: 45 pages, 11 figures
Sparse Models for Machine Learning
Creators: name: Lin, Jianyi
Publisher: name: arXiv
Year: 2023
Subjects: subject: Machine Learning (cs.LG)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences
subject: I.5.4; I.2.6; G.1.3

description: The sparse modeling is an evident manifestation capturing the parsimony principle just described, and sparse models are widespread in statistics, physics, information sciences, neuroscience, computational mathematics, and so on. In statistics the many applications of sparse modeling span regression, classification tasks, graphical model selection, sparse M-estimators and sparse dimensionality reduction. It is also particularly effective in many statistical and machine learning areas where the primary goal is to discover predictive patterns from data which would enhance our understanding and control of underlying physical, biological, and other natural processes, beyond just building accurate outcome black-box predictors. Common examples include selecting biomarkers in biological procedures, finding relevant brain activity locations which are predictive about brain states and processes based on fMRI data, and identifying network bottlenecks best explaining end-to-end performance. Moreover, the research and applications of efficient recovery of high-dimensional sparse signals from a relatively small number of observations, which is the main focus of compressed sensing or compressive sensing, have rapidly grown and became an extremely intense area of study beyond classical signal processing. Likewise interestingly, sparse modeling is directly related to various artificial vision tasks, such as image denoising, segmentation, restoration and superresolution, object or face detection and recognition in visual scenes, and action recognition. In this manuscript, we provide a brief introduction of the basic theory underlying sparse representation and compressive sensing, and then discuss some methods for recovering sparse solutions to optimization problems in effective way, together with some applications of sparse recovery in a machine learning problem known as sparse dictionary learning.
description: 42 pages
Position-Agnostic Autonomous Navigation in Vineyards with Deep Reinforcement Learning
Creators: name: Martini, Mauro
name: Cerrato, Simone
name: Salvetti, Francesco
name: Angarano, Simone
name: Chiaberge, Marcello
Publisher: name: arXiv
Year: 2022
Subjects: subject: Robotics (cs.RO)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Precision agriculture is rapidly attracting research to efficiently introduce automation and robotics solutions to support agricultural activities. Robotic navigation in vineyards and orchards offers competitive advantages in autonomously monitoring and easily accessing crops for harvesting, spraying and performing time-consuming necessary tasks. Nowadays, autonomous navigation algorithms exploit expensive sensors which also require heavy computational cost for data processing. Nonetheless, vineyard rows represent a challenging outdoor scenario where GPS and Visual Odometry techniques often struggle to provide reliable positioning information. In this work, we combine Edge AI with Deep Reinforcement Learning to propose a cutting-edge lightweight solution to tackle the problem of autonomous vineyard navigation without exploiting precise localization data and overcoming task-tailored algorithms with a flexible learning-based approach. We train an end-to-end sensorimotor agent which directly maps noisy depth images and position-agnostic robot state information to velocity commands and guides the robot to the end of a row, continuously adjusting its heading for a collision-free central trajectory. Our extensive experimentation in realistic simulated vineyards demonstrates the effectiveness of our solution and the generalization capabilities of our agent.
Multi-wavelength temporal and spectral study of PKS 0402-362
Creators: name: Das, Avik kumar
name: Mondal, Sandeep Kumar
name: Prince, Raj
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We study the long-term behavior of the bright gamma-ray blazar PKS 0402-362. Over a span of approximately 12.5 years, from August 2008 to January 2021, we gathered Fermi-LAT temporal data and identified three distinct periods of intense $γ$-ray activity. Notably, the second period exhibited the highest brightness ever observed in this particular source. We observed most of the $γ$-ray flare peaks to be asymmetric in profile suggesting a slow cooling time of particles or the varying Doppler factor as the main cause of these flares. The $γ$-ray spectrum is fitted with power-law and log-parabola models, and in both cases, the spectral index is very steep. The lack of time lags between optical-IR and $γ$-ray emissions indicates the presence of a single-zone emission model. Using this information, we modeled the broadband SEDs with a simple one-zone leptonic model using the publicly available code `GAMERA'. The particle distribution index is found to be the same as expected in diffusive shock acceleration suggesting it as the main mechanism of particle acceleration to very high energy up to 4 - 6 GeV. During the different flux phases, we observed that the thermal disk dominates the optical emission, indicating that this source presents a valuable opportunity to investigate the connection between the disk and the jet.
description: 8 pages, 1 figure, The 38th International Cosmic Ray Conference (ICRC2023) proceedings
title: Longitudinal and transverse piezoelectric effects of ferroelectret metamaterials with positive and negative Poisson's ratios
Creators: name: Hu, Qianqian
name: Zhang, Tongyan
name: Sessler, Gerhard M.
name: Seggern, Heinz von
name: Altmann, Alexander A.
name: Kupnik, Mario
name: Shi, Zhiming
name: Zhang, Xiaoqing
Publisher: name: AIP Publishing
Year: 2025

description: A theoretical model has been developed to express the longitudinal and transverse piezoelectric effects in ferro/piezoelectrets. This model is an extension of the classic model based on layer-dielectric structures that focuses on the longitudinal piezoelectric effect. The improved model reveals that the relation between the longitudinal piezoelectric d₃₃ coefficient and the transverse piezoelectric d₃₁ coefficient is associated with Poisson's ratio μ₁₃ (or μ₃₁) and Young's moduli Y₁ and Y₃. The polarity of the two coefficients is opposite for materials with a positive Poisson's ratio as normally observed in conventional piezoelectric materials, and the same for materials with a negative Poisson's ratio, i.e., auxetic materials. The experimental results available in the literature and obtained from ferroelectret metamaterials with a honeycomb cross-sectional structure and two-dimensional (2D) symmetric structure, called 2D ferroelectret metamaterials, designed and prepared in this study reasonably agree with theoretical predictions. This study not only extends the scope of the metamaterials by inducing the concept of ferroelectret metamaterials but also provides a strategy for designing ferroelectrets with designable properties.
Doubly Charged Higgs Boson Production at Hadron Colliders II: A Zee-Babu Case Study
Creators: name: Ruiz, Richard
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Motivated by searches for so-called leptonic scalars at the LHC and the recent measurement of the $W$ boson's mass at the Tevatron, we revisit the phenomenology of the Zee-Babu model for neutrino masses and the ability to differentiate it from the Type II Seesaw model at the LHC. We conclude that this task is much more difficult than previously believed. All inputs equal in the two scenarios, we find that total and differential rates for producing pairs of doubly and singly charged scalars are identical in shape and only differ in normalization. The normalization is given by the ratio of hadronic cross sections and can be unity. Differences in cross sections are small and can be hidden by unknown branching rates. This holds for Drell-Yan, $γγ$ fusion, and $gg$ fusion, as well as observables at LO and NLO in QCD. This likeness allows us to reinterpret Run II limits on the Type II Seesaw and estimate projections for the HL-LHC. Using updated neutrino oscillation data, we also find that some collider observables, e.g., lepton flavor-violating branching ratios, are now sufficiently precise to provide a path forward. Other means of discrimination are also discussed. As a byproduct of this work, we report the availability of new Universal \texttt{FeynRules} Object libraries, the \texttt{SM\_ZeeBabu} UFO, that enable fully differential simulations up to NLO+LL(PS) with tool chains employing \texttt{MadGraph5\_aMC@NLO}.
description: Journal version: add'l discussions on low-energy connections, results unchanged. 51 pages (total), including appendices (6 pages), 11 tables, and 9 figures. New UFO available from FeynRules database https://feynrules.irmp.ucl.ac.be/wiki/ZeeBabu and analysis code available from gitlab https://gitlab.cern.ch/riruiz/public-projects/-/tree/master/ZeeBabu_LHC_Update Happy Fall!
Machine learning-based prediction of Q-voter model in complex networks
Creators: name: Pineda, Aruane M.
name: Kent, Paul
name: Connaughton, Colm
name: Rodrigues, Francisco A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Physics and Society (physics.soc-ph)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Social and Information Networks (cs.SI)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: In this article, we consider machine learning algorithms to accurately predict two variables associated with the $Q$-voter model in complex networks, i.e., (i) the consensus time and (ii) the frequency of opinion changes. Leveraging nine topological measures of the underlying networks, we verify that the clustering coefficient (C) and information centrality (IC) emerge as the most important predictors for these outcomes. Notably, the machine learning algorithms demonstrate accuracy across three distinct initialization methods of the $Q$-voter model, including random selection and the involvement of high- and low-degree agents with positive opinions. By unraveling the intricate interplay between network structure and dynamics, this research sheds light on the underlying mechanisms responsible for polarization effects and other dynamic patterns in social systems. Adopting a holistic approach that comprehends the complexity of network systems, this study offers insights into the intricate dynamics associated with polarization effects and paves the way for investigating the structure and dynamics of complex systems through modern machine learning methods.
description: 32 pages, 10 figures
Differential regulation of cytokine-induced major histocompatibility complex class II expression and nitric oxide release in rat microglia and astrocytes by effectors of tyrosine kinase, protein kinase C, and cAMP
Creators: name: Hellendall, R.P.
name: Ting, J.P.-Y.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 1997

description: Two glial cell populations of the CNS, astrocytes and microglia, were examined for expression of two immunologically important molecules, MHC class II and nitric oxide (NO), following treatment with cytokines. IFN-γ induced both molecules in microglia at substantially higher levels than astrocytes. The addition of TNF-α to IFN-γ elevated class II expression and NO in both cells. Genistein, an inhibitor of tyrosine kinases, and calphostin, an inhibitor of protein kinase C, diminished cytokine induction of class II MHC and NO in both glial populations. Forskolin was most effective in inhibiting class II MHC expression, but had little inhibitory effect on NO production. These results indicate microglia are more effective than astrocytes in producing cell-associated and secreted immune mediators in response to IFN-γ and or TNF-α and multiple parallel, but distinct, signaling events are required for cytokine induced class II MHC or NO production.
Intrasaccadic motion streaks jump-start gaze correction
Creators: name: Schweitzer, Richard
name: Rolfs, Martin
Publisher: name: Humboldt-Universität zu Berlin
Year: 2021
Subjects: subject: 004 Informatik

description: Rapid eye movements (saccades) incessantly shift objects across the retina. To establish object correspondence, the visual system is thought to match surface features of objects across saccades. Here, we show that an object’s intrasaccadic retinal trace—a signal previously considered unavailable to visual processing—facilitates this match making. Human observers made saccades to a cued target in a circular stimulus array. Using high-speed visual projection, we swiftly rotated this array during the eyes’ flight, displaying continuous intrasaccadic target motion. Observers’ saccades landed between the target and a distractor, prompting secondary saccades. Independently of the availability of object features, which we controlled tightly, target motion increased the rate and reduced the latency of gaze-correcting saccades to the initial presaccadic target, in particular when the target’s stimulus features incidentally gave rise to efficient motion streaks. These results suggest that intrasaccadic visual information informs the establishment of object correspondence and jump-starts gaze correction.
Ejected Particles after Impact Splash on Mars: Aggregates and Aerodynamics
Creators: name: Becker, Tim
name: Teiser, Jens
name: Jardiel, Teresa
name: Peiteado, Marco
name: Muñoz, Olga
name: Martikainen, Julia
name: Martin, Juan Carlos Gomez
name: Merrison, Jonathan
name: Wurm, Gerhard
Publisher: name: arXiv
Year: 2023
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Our earlier laboratory measurements showed that low-velocity sand impacts release fine <5 μm dust from a Martian simulant soil. This dust will become airborne in the Martian atmosphere. Here, we extend this study by measuring aerodynamic properties of ejecta and characterizing deviations from the behavior of spherical, monolithic grains. We observe the settling of particles emitted as part of an impact splash. The sizes (20 to 280 μm) and sedimentation velocities (0.1 to 0.8 ms^{-1} ) of the particles are deduced from high-speed videos while the particles sediment under low ambient pressure of about 1 mbar. The particles regularly settle slower than expected, down to a factor of about 0.3. Using optical microscopy, the shape of the captured particles is characterized by simple axis ratios (longest/smallest), which show that the vast majority of particles are irregular but typically not too elongated, with axis ratios below 2 on average. Electron microscopy further reveals that the particles are typically porous aggregates, which is the most likely reason for the reduction of the sedimentation velocity. Due to the reduced bulk density, aggregates up to 10 μm in diameter should regularly be a part of the dust in the Martian atmosphere.
description: 8 pages, 7 figures
D-JRP-PARADISE-WP3.1. Report on the in-silico selection of highly polymorphic sequences in C. parvum and G. duodenalis genomes
Creators: name: Caccio, Simone Mario
Publisher: name: Zenodo
Year: 2021
Subjects: PARADISE; Cryptosporidium parvum; Giardia duodenalis

description: Deliverable D-JRP-PARADISE-WP3.1 of the PARADISE project. The document illustrates the procedures used to analyze whole genome data for the identification of genomic regions of high variability
Identification of an interferon-γ-responsive element of a class II major histocompatibility gene in rat type 1 astrocytes
Creators: name: Moses, H.
name: Sasaki, A.
name: Ting, J.P.-Y.
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 1991

description: Interferon-γ(IFN-γ) has been shown to induce class II major histocompatibility complex (MHC) antigens on several cell types. Previous analysis of cell lines including a glioblastoma multiforme line by our laboratory has mapped an IFN-γ-responsive element to the upstream -141 to -109 base pair (bp) region of the DRA promoter. Using deletion mutants, this report shows that this same general region (-135 to -109 bp) is important for IFN-γ induction in two other human glioma lines and more importantly in primary astrocytes. We have confirmed that this regulatory region of the HLA-DRA gene is necessary for IFN-γ inducibility in astrocytes using a substitution mutant. Sequences beyond -135 bp do not appear to have any additional positive or negative elements.
Virial Theorem for Non-relativistic Quantum Fields in D Spatial Dimensions
Creators: name: Lin, Chris L.
name: Ordonez, Carlos R.
Publisher: name: arXiv
Year: 2015
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The virial theorem for non-relativistic complex fields in $D$ spatial dimensions and with arbitrary many-body potential is derived, using path-integral methods and scaling arguments recently developed to analyze quantum anomalies in low-dimensional systems. The potential appearance of a Jacobian $J$ due to a change of variables in the path-integral expression for the partition function of the system is pointed out, although in order to make contact with the literature most of the analysis deals with the $J=1$ case. The virial theorem is recast into a form that displays the effect of microscopic scales on the thermodynamics of the system. From the point of view of this paper the case usually considered, $J=1$, is not natural, and the generalization to the case $J\neq 1$ is briefly presented.
description: 6 pages (this version is the published version)