cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Phase change events of volatile liquid perfluorocarbon contrast agents produce unique acoustic signatures
Creators: name: Dayton, Paul A
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2014

description: Phase-change contrast agents (PCCAs) provide a dynamic platform to approach problems in medical ultrasound (US). Upon US-mediated activation, the liquid core vaporizes and expands to produce a gas bubble ideal for US imaging and therapy. In this study, we demonstrate through high-speed video microscopy and US interrogation that PCCAs composed of highly volatile perfluorocarbons (PFCs) exhibit unique acoustic behavior that can be detected and differentiated from standard microbubble contrast agents. Experimental results show that when activated with short pulses PCCAs will over-expand and undergo unforced radial oscillation while settling to a final bubble diameter. The size-dependent oscillation phenomenon generates a unique acoustic signal that can be passively detected in both time and frequency domain using confocal piston transducers with an ‘activate high’ (8 MHz, 2 cycles), ‘listen low’ (1 MHz) scheme. Results show that the magnitude of the acoustic ‘signature’ increases as PFC boiling point decreases. By using a band-limited spectral processing technique, the droplet signals can be isolated from controls and used to build experimental relationships between concentration and vaporization pressure. The techniques shown here may be useful for physical studies as well as development of droplet-specific imaging techniques.
Globalisation and criminal justice: an interactive collaborative approach to global learning
Creators: name: Pickering, Sharon
name: Wonders, Nancy
name: Danner, Mona
name: Weaver, Debbi
Publisher: name: La Trobe
Year: 2023

description: This paper outlines the use of WebCT in a collaborative assessment project between an Australian and two US universities. Informed by global trends, criminal justice practitioners increasingly move through different jurisdictions and cultural contexts. We wanted to work with students and have students work with each other in ways that prepared them to operate in international surroundings in relation to international law and the transnationalisation of criminal justice agencies. The Global Project required students to engage in a series of online activities with the aim of fostering online and international co -operation between students. Moreover, as students were studying globalisation and criminal justice, it was designed to engage students in the processes and experiences of globalisation. The use of online learning technologies in fostering the internationalisation of curriculum and developing alternative group learning strategies has offered a series of challenges which require critical reflection on the ways we globalise learning.
Circular Polarization of Pulsar Wind Nebulae and the Cosmic-Ray Positron Excess
Creators: name: Linden, Tim
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Recent observations by the PAMELA and AMS-02 telescopes have uncovered an anomalous rise in the positron fraction at energies above 10~GeV. One possible explanation for this excess is the production of primary electron/positron pairs through electromagnetic cascades in pulsar magnetospheres. This process results in a high multiplicity of electron/positron pairs within the wind-termination shock of pulsar wind nebula (PWN). A consequence of this scenario is that no circular polarization should be observed within PWN, since the contributions from electrons and positrons exactly cancel. Here we note that current radio instruments are capable of setting meaningful limits on the circular polarization of synchrotron radiation in PWNs, which observationally test the model for pulsar production of the local positron excess. The observation of a PWN with detectable circular polarization would cast strong doubt on pulsar interpretations of the positron excess, while observations setting strong limits on the circular polarization of PWN would lend credence to these models. Finally, we indicate which pulsar wind nebulae are likely to provide the best targets for observational tests of the AMS-02 excess.
description: 6 pages, 3 Figures
Carl Philipp Emanuel Bachs "Avertissement" über den Druck der Kunst der Fuge
Creators: name: Wilhelmi, Thomas
Publisher: name: Bach-Jahrbuch
Year: 2018

description: Der Subskriptionsaufruf in den Critischen Nachrichten aus dem Reiche der Gelehrsamkeit vom 7. Mai 1751 stammt höchstwahrscheinlich von Carl Philipp Emanuel Bach und wird im vorliegenden Beitrag als Bach-Quelle untersucht.
description: Bach-Jahrbuch, Bd. 78 (1992)
Unconventional gap dependence of high harmonic generation in the extremely strong light-matter coupling regime
Creators: name: Kofuji, Akira
name: Peters, Robert
Publisher: name: arXiv
Year: 2023
Subjects: subject: Optics (physics.optics)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: High harmonic generation(HHG) is one of the most commonly studied nonlinear optical phenomena, originating in the ultrafast dynamics of electrons in atomic gasses and semiconductors. It has attracted much attention because of its non-perturbative nature and potential for future attosecond laser pulse sources. On the theory side, a semi-classical picture based on tunneling ionization of electrons is successfully used in explaining key characteristics of the HHG. This model assumes that electric fields non-perturbatively excite electrons beyond the ionization potential or band gap. Thus, intuitively, a larger gap should lead to an exponentially smaller HHG emission. Despite this intuition, the HHG in the Mott insulator Ca2RuO4 has shown an unconventional exponential increase with respect to the gap width. This experiment implies effects beyond the semi-classical theory. However, most theoretical works have focused on the dependence of the HHG on external control parameters, and the gap dependence of the HHG is poorly understood even in non interacting systems. Thus, it is essential to clarify the gap dependence of the HHG in a fully quantum mechanical approach. Here, we analyze numerically exactly the gap dependence of the HHG in two-level systems. We find an increase in the strength of the HHG when the Rabi frequency is large compared to the gap width. Furthermore, the relaxation and scattering of electrons increase the visibility of this gap dependence. Finally, we find that the enhancement rate follows a universal scaling law regardless of the driving frequency. The existence of this gap dependence in two-level systems suggests that this unconventional gap dependence is a universal behavior that can be found not only in Mott insulators but also in atomic gasses and semiconductors.
Eclipses and dust formation by WC9 type Wolf-Rayet stars
Creators: name: Williams, P. M.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Visual photometry of 16 WC8-9 dust-making Wolf-Rayet (WR) stars during 2001--2009 was extracted from the All Sky Automated Survey All Star Catalogue (ASAS-3) to search for eclipses attributable to extinction by dust formed in clumps in our line of sight. Data for a comparable number of dust-free WC6-9 stars were also examined to help characterise the dataset. Frequent eclipses were observed from WR 104, and several from WR 106, extending the 1994-2001 studies by Kato et al. (2002a,b), but not supporting their phasing the variations in WR 104 with its `pinwheel' rotation period. Only four other stars showed eclipses, WR 50 (one of the dust-free stars), WR 69, WR 95 and WR 117, and there may have been an eclipse by WR 121, which had shown two eclipses in the past. No dust eclipses were shown by the `historic' eclipsers WR 103 and WR 113. The atmospheric eclipses of the latter were observed but the suggestion by David-Uraz et al. (2012) that dust may be partly responsible for these is not supported. Despite its frequent eclipses, there is no evidence in the infrared images of WR 104 for dust made in its eclipses, demonstrating that any dust formed in this process is not a significant contributor to its circumstellar dust cloud and suggesting that the same applies to the other stars showing fewer eclipses.
description: 9 page, 12 figures
Collaborative regression-based anatomical landmark detection
Creators: name: Shen, Dinggang
name: Gao, Yaozong
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Anatomical landmark detection plays an important role in medical image analysis, e.g., for registration, segmentation and quantitative analysis. Among various existing methods for landmark detection, regression-based methods recently have drawn much attention due to robustness and efficiency. In such methods, landmarks are localized through voting from all image voxels, which is completely different from classification-based methods that use voxel-wise classification to detect landmarks. Despite robustness, the accuracy of regression-based landmark detection methods is often limited due to 1) inclusion of uninformative image voxels in the voting procedure, and 2) lack of effective ways to incorporate inter-landmark spatial dependency into the detection step. In this paper, we propose a collaborative landmark detection framework to address these limitations. The concept of collaboration is reflected in two aspects. 1) Multi-resolution collaboration. A multi-resolution strategy is proposed to hierarchically localize landmarks by gradually excluding uninformative votes from faraway voxels. Moreover, for the informative voxels near the landmark, a spherical sampling strategy is also designed in the training stage to improve their prediction accuracy. 2) Inter-landmark collaboration. A confidence-based landmark detection strategy is proposed to improve the detection accuracy of “difficult-to-detect” landmarks by using spatial guidance from “easy-to-detect” landmarks. To evaluate our method, we conducted experiments extensively on three datasets for detecting prostate landmarks and head & neck landmarks in computed tomography (CT) images, and also dental landmarks in cone beam computed tomography (CBCT) images. The results show the effectiveness of our collaborative landmark detection framework in improving landmark detection accuracy, compared to other state-of-the-art methods.
The influence of beam focus during laser powder bed fusion of a high reflectivity aluminium alloy -- AlSi$_{10}$Mg
Creators: name: Patel, Sagar
name: Chen, Haoxiu
name: Vlasea, Mihaela
name: Zou, Yu
Publisher: name: arXiv
Year: 2021
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: LPBF of Al alloys is associated with numerous challenges when compared to other commonly used alloys due to their higher reflectivity and thermal conductivity. In this work, processing diagrams, temperature prediction models, XCT, and metallography are used for establishing criteria in process parameter optimization of high reflectivity Al alloys based on AlSi$_{10}$Mg response in using 57 different process parameter combinations - 21 using a focused Gaussian laser beam and 36 using divergent beams. For LPBF systems with focused beam diameters <100 μm, divergent beams obtained by defocusing to a position above the LPBF build plate primarily lead to conduction mode melt pools, while a focused beam leads to transition and keyhole mode melt pools. Conduction mode melting helps in avoiding keyhole mode defects, resulting in parts with densities >99.98%. Additionally, an analytical model-guided selection of laser power and velocity settings for a focused beam help in stabilizing melt pool and spatter dynamics in the transition melting mode thereby enabling a potential to obtain density values close to conduction mode densities (~99.98%). A dimensionless keyhole number (Ke) was derived in this work to identify distinct regions of conduction (Ke of 0-12), transition (Ke of 12-20), and keyhole (Ke > 20) mode melting during LPBF of AlSi$_{10}$. A melt pool aspect ratio (ratio of melt pool depth to width) of ~0.4 is observed to be the threshold between conduction and transition/keyhole mode melt pools for AlSi$_{10}$, different from the conventionally assumed 0.5. Lastly, inferred laser absorptivity values (from experimental melt pools) of transition/keyhole mode melt pools are observed to be >40% higher when compared to conduction mode melt pools. This work demonstrates a dimensionless-process map method to obtain near fully dense parts that can be generalized for LPBF of high reflectivity alloys.
Zu Wilhelm Friedemann Bachs Berliner Jahren
Creators: name: Henzel, Christoph
Publisher: name: Bach-Jahrbuch
Year: 2018

description: Der Beitrag gibt einen Überblick übder den Forschungsstand zu Bachs Berliner Lebensjahren und versucht, diese anhand der genannten wie neu hinzugezogener Quellen möglichst umfassend darzustellen. Vergleiche auch: Christoph Henzel: Nachtrag zu Wilhelm Friedemann Bachs Berliner Jahren. BJ 2004, S. 229-232 Christoph Henzel: "... da er sich erklähret hat, was an die Armen zu geben ...". Zu einem Berliner Konzert Wilhelm Friedemann Bachs. BJ 2012, S. 251-253
description: Bach-Jahrbuch, Bd. 78 (1992)
Response from Stan Graves to Richard Strimel, Staff Post 12 Closet Installation, Fort Sam Houston, Texas
Creators: name: Graves, Stanley O.
Publisher: name: Texas Historical Commission
Year: 1990
Subjects: subject: JBSA-Sam Houston
valueUri: https://core.tdar.org/browse/geographic-keyword/82532/jbsa-sam-houston
subject: San Antonio
valueUri: https://core.tdar.org/browse/geographic-keyword/4149/san-antonio
subject: Bexar (County)
valueUri: https://core.tdar.org/browse/geographic-keyword/4150/bexar-county
subject: Texas
valueUri: https://core.tdar.org/browse/geographic-keyword/6923/texas
subject: Historic
valueUri: https://core.tdar.org/browse/culture-keyword/25/historic
subject: Governmental Structure
valueUri: https://core.tdar.org/browse/site-type/318/governmental-structure
subject: Historic Governmental Structure
valueUri: https://core.tdar.org/browse/site-type/320/historic-governmental-structure
subject: Non-Domestic Structures
valueUri: https://core.tdar.org/browse/site-type/309/non-domestic-structures
subject: Staff Post 12
valueUri: https://core.tdar.org/browse/other-keyword/154283/staff-post-12
subject: Closet Installation
valueUri: https://core.tdar.org/browse/other-keyword/154284/closet-installation
subject: Architectural Documentation
valueUri: https://core.tdar.org/browse/investigation-type/16/architectural-documentation
subject: Heritage Management
valueUri: https://core.tdar.org/browse/investigation-type/24/heritage-management

description: The Texas Historical Commission writes that they have received Fort Sam Houston's letter documenting a recent site visit and can now determine "no effect" on Staff Post #12 for the installation of interior bedroom closets.
From Torus Bundles to Particle-Hole Equivariantization
Creators: name: Cui, Shawn X.
name: Gustafson, Paul
name: Qiu, Yang
name: Zhang, Qing
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Algebra (math.QA)
subject: Mathematical Physics (math-ph)
subject: Geometric Topology (math.GT)
subject: Quantum Physics (quant-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We continue the program of constructing (pre)modular tensor categories from 3-manifolds first initiated by Cho-Gang-Kim using $M$ theory in physics and then mathematically studied by Cui-Qiu-Wang. An important structure involved is a collection of certain $\text{SL}(2, \mathbb{C})$ characters on a given manifold which serve as the simple object types in the corresponding category. Chern-Simons invariants and adjoint Reidemeister torsions play a key role in the construction, and they are related to topological twists and quantum dimensions, respectively, of simple objects. The modular $S$-matrix is computed from local operators and follows a trial-and-error procedure. It is currently unknown how to produce data beyond the modular $S$- and $T$-matrices. There are also a number of subtleties in the construction which remain to be solved. In this paper, we consider an infinite family of 3-manifolds, that is, torus bundles over the circle. We show that the modular data produced by such manifolds are realized by the $\mathbb{Z}_2$-equivariantization of certain pointed premodular categories. Here the equivariantization is performed for the $\mathbb{Z}_2$-action sending a simple (invertible) object to its inverse, also called the particle-hole symmetry. It is our hope that this extensive class of examples will shed light on how to improve the program to recover the full data of a premodular category.
description: 16 pages, minor changes, to appear in Lett Math Phys
Density-functional theory approach to the thermodynamics of the harmonically confined one-dimensional Hubbard model
Creators: name: Campo, V. L.
Publisher: name: arXiv
Year: 2014
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: The thermodynamics of the inhomogeneous one-dimensional repulsive fermionic Hubbard model with parabolic confinement is studied by a density-functional theory approach, based on Mermin's generalization to finite temperatures. A local-density approximation (LDA), based on exact results for the homogeneous model, is used to approximate the correlation part in the Helmholtz free-energy, comprising the thermodynamic Bethe ansatz LDA (TBALDA). The general presentation of the method is given and some properties of the homogeneous model that are relevant to the DFT approach are analyzed. Extensive comparison between TBALDA and numerical exact diagonalization results for thermodynamic properties of small inhomogeneous chains is discussed. In the remaining, a classical thermodynamic treatment of the confined system is developed with the focus on global properties of large systems. A unusual behavior under isentropic expansion is found and discussed.
description: 16 pages, 10 figures
Free Energy Landscapes, Diffusion Coefficients, and Kinetic Rates from Transition Paths
Creators: name: Palacio-Rodriguez, Karen
name: Pietrucci, Fabio
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We address the problem of constructing accurate mathematical models of the dynamics of complex systems projected on a collective variable. To this aim we introduce a conceptually simple yet effective algorithm for estimating the parameters of Langevin and Fokker-Planck equations from a set of short, possibly out-of-equilibrium molecular dynamics trajectories, obtained for instance from transition path sampling or as relaxation from high free-energy configurations. The approach maximizes the model likelihood based on any explicit expression of the short-time propagator, hence it can be applied to different evolution equations. We demonstrate the numerical efficiency and robustness of the algorithm on model systems, and we apply it to reconstruct the projected dynamics of pairs of C60 and C240 fullerene molecules in explicit water. Our methodology allows reconstructing the accurate thermodynamics and kinetics of activated processes, namely free energy landscapes, diffusion coefficients, and kinetic rates. Compared to existing enhanced sampling methods, we directly exploit short unbiased trajectories at a competitive computational cost.
Synthesis and antioxidant activity of some pyrazole-based heterocycles using a 2(3H)-furanone building block
Creators: name: Youssef, Youssef M.
name: Azab, Mohammad E.
name: Elsayed, Galal A.
name: El-Sayed, Amira A.
name: Hassaballah, Aya I.
name: El-Helw, Eman A. E.
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Neuroscience
subject: Pharmacology
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 111714 Mental Health
subject: FOS: Health sciences

description: Some pyrazole-based heterocycles, such as pyrrolone, pyridazinone, and imidazole derivatives were synthesized utilizing the pyrazolyl-2(3H)-furanone derivative 3, which was obtained in a good yield via Perkin condensation of 5-chloro-4-formyl-3-methyl-1-phenylpyrazole with 3-(4-methylbenzoyl)propionic acid in the presence of cyclo-dehydrating agent (sodium acetate and acetic anhydride). Also, the acid hydrazide obtained was reacted with some carbonyl reagents like acetic anhydride, benzoyl chloride, 4-chlorobenzaldehyde, and 1,3-diphenyl-4-formylpyrazole, aiming to achieve new pyrrolone derivatives. The antioxidant activity screening of some synthesized compounds demonstrated that pyridazinone and N-phenylhydrazide derivatives showed the most exceptional potencies.
The Challenges Facing Staff Development In Promoting Quality Online Teaching
Creators: name: Weaver, Debbi
Publisher: name: La Trobe
Year: 2023

description: This paper outlines the use of WebCT in a collaborative assessment project between an Australian and two US universities. Informed by global trends, criminal justice practitioners increasingly move through different jurisdictions and cultural contexts. We wanted to work with students and have students work with each other in ways that prepared them to operate in international surroundings in relation to international law and the transnationalisation of criminal justice agencies. The Global Project required students to engage in a series of online activities with the aim of fostering online and international co -operation between students. Moreover, as students were studying globalisation and criminal justice, it was designed to engage students in the processes and experiences of globalisation. The use of online learning technologies in fostering the internationalisation of curriculum and developing alternative group learning strategies has offered a series of challenges which require critical reflection on the ways we globalise learning.
Johann Christian Bach und die Freimaurer-Loge zu den Neun Musen in London
Creators: name: Warburton, Ernest
Publisher: name: Bach-Jahrbuch
Year: 2018

description: Die bis dato unbekannte Freimaurerschaft Johann Christian Bachs steht im Zentrum des Beitrags. Neben Bekanntschaften, die seine Londoner Logenmitgliedschaft mit sich gebrachte haben dürfte, werden besonders die musikalischen Aktivitäten der Londoner Freimaurer dargestellt, wobei offen bleibt, ob Bach hier auch kompositorisch aktiv war.
description: Bach-Jahrbuch, Bd. 78 (1992)
Renormalization Group Analysis of a Fermionic Hot Spot Model
Creators: name: Whitsitt, Seth
name: Sachdev, Subir
Publisher: name: arXiv
Year: 2014
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present a renormalization group (RG) analysis of a fermionic "hot spot" model of interacting electrons on the square lattice. We truncate the Fermi surface excitations to linearly dispersing quasiparticles in the vicinity of eight hot spots on the Fermi surface, with each hot spot separated from another by the wavevector $(π, π)$. This motivated by the importance of these Fermi surface locations to the onset of antiferromagnetic order; however, we allow for all possible quartic interactions between the fermions, and also for all possible ordering instabilities. We compute the RG equations for our model, which depend on whether the hot spots are perfectly nested or not, and relate our results to earlier models. We also compute the RG flow of the relevant order parameters for both Hubbard and $J$, $V$ interactions, and present our results for the dominant instabilities in the nested and non-nested cases. In particular, we find that non-nested hot spots with $J$, $V$ interactions have competing singlet $d_{x^2-y^2}$ superconducting and $d$-form factor incommensurate density wave instabilities. We also investigate the enhancement of incommensurate density waves near experimentally observed wavevectors, and find dominant $d$-form factor enhancement for a range of couplings.
Autonomous Navigation System for a Delivery Drone
Creators: name: Miranda, Victor R. F.
name: Rezende, Adriano M. C.
name: Rocha, Thiago L.
name: Azpúrua, Héctor
name: Pimenta, Luciano C. A.
name: Freitas, Gustavo M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: Systems and Control (eess.SY)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: The use of delivery services is an increasing trend worldwide, further enhanced by the COVID pandemic. In this context, drone delivery systems are of great interest as they may allow for faster and cheaper deliveries. This paper presents a navigation system that makes feasible the delivery of parcels with autonomous drones. The system generates a path between a start and a final point and controls the drone to follow this path based on its localization obtained through GPS, 9DoF IMU, and barometer. In the landing phase, information of poses estimated by a marker (ArUco) detection technique using a camera, ultra-wideband (UWB) devices, and the drone's software estimation are merged by utilizing an Extended Kalman Filter algorithm to improve the landing precision. A vector field-based method controls the drone to follow the desired path smoothly, reducing vibrations or harsh movements that could harm the transported parcel. Real experiments validate the delivery strategy and allow to evaluate the performance of the adopted techniques. Preliminary results state the viability of our proposal for autonomous drone delivery.
description: 12 pages, 15 figures, extended version of an paper published at the XXIII Brazilian Congress of Automatica, entitled "Desenvolvimento de um drone aut\^onomo para tarefas de entrega de carga"
NLO QCD predictions for off-shell $t\bar{t}W$ production in association with a light jet at the LHC
Creators: name: Bi, Huan-Yu
name: Kraus, Manfred
name: Reinartz, Minos
name: Worek, Malgorzata
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In view of the persisting tension between theoretical predictions and the LHC data for the $pp \to t\bar{t}W^\pm$ production process, we present the state-of-the-art full off-shell NLO QCD result for $pp \to t\bar{t}W^+\, j+X$. We concentrate on the multi-lepton decay channel at the LHC with $\sqrt{s}= 13$ TeV. In our calculation off-shell top quarks and gauge bosons are described by Breit-Wigner propagators, furthermore, double-, single- as well as non-resonant top-quark contributions along with all interference effects are consistently incorporated at the matrix element level. We present results for both integrated and differential fiducial cross sections for various renormalisation and factorisation scale settings and different PDF sets. With a fairly inclusive choice of cuts and regardless of the scale and PDF choice, non-flat differential ${\cal K}$-factors are obtained for many observables that we have examined. Since from an experimental point of view, both processes $pp \to t\bar{t}W^\pm j+X$ and $pp\to t\bar{t}W^\pm +X$ consist of similar final states we investigate the effect of additional jet activity on the integrated and differential fiducial cross sections. For this purpose, the normalised differential distributions for $pp \to e^+ν_e\, μ^-\barν_μ\, τ^+ν_τ\, b\bar{b} \,j+X$ and $pp \to e^+ν_e\, μ^-\barν_μ\, τ^+ν_τ\, b\bar{b} +X$ are compared. The theoretical results for the latter process are also recalculated.
description: 33 pages, 13 figures, 10 tables, a few typos corrected after proofreading, version to appear in JHEP
High-level Features for Resource Economy and Fast Learning in Skill Transfer
Creators: name: Ahmetoglu, Alper
name: Ugur, Emre
name: Asada, Minoru
name: Oztop, Erhan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Robotics (cs.RO)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Abstraction is an important aspect of intelligence which enables agents to construct robust representations for effective decision making. In the last decade, deep networks are proven to be effective due to their ability to form increasingly complex abstractions. However, these abstractions are distributed over many neurons, making the re-use of a learned skill costly. Previous work either enforced formation of abstractions creating a designer bias, or used a large number of neural units without investigating how to obtain high-level features that may more effectively capture the source task. For avoiding designer bias and unsparing resource use, we propose to exploit neural response dynamics to form compact representations to use in skill transfer. For this, we consider two competing methods based on (1) maximum information compression principle and (2) the notion that abstract events tend to generate slowly changing signals, and apply them to the neural signals generated during task execution. To be concrete, in our simulation experiments, we either apply principal component analysis (PCA) or slow feature analysis (SFA) on the signals collected from the last hidden layer of a deep network while it performs a source task, and use these features for skill transfer in a new target task. We compare the generalization performance of these alternatives with the baselines of skill transfer with full layer output and no-transfer settings. Our results show that SFA units are the most successful for skill transfer. SFA as well as PCA, incur less resources compared to usual skill transfer, whereby many units formed show a localized response reflecting end-effector-obstacle-goal relations. Finally, SFA units with lowest eigenvalues resembles symbolic representations that highly correlate with high-level features such as joint angles which might be thought of precursors for fully symbolic systems.
Nochmals: Die Verwendung der Blechblasinstrumente bei J. S. Bach
Creators: name: MacCracken, Thomas G.
Publisher: name: Bach-Jahrbuch
Year: 2018

description: In der andauernden Kontroverse mit Don L. Smithers (Links s.u.) verteidigt der Autor verschiedene bereits 1984 von ihm vorgebrachte Standpunkte gegen die inzwischen erhobenen Anfechtungen. Vergleiche auch: Thomas G. MacCracken: Die Verwendung der Blechblasinstrumente bei J. S. Bach unter besonderer Berücksichtigung der Tromba da tirarsi. BJ 1984, S. 59-90 Don L. Smithers: Gottfried Reiches Ansehen und sein Einfluß auf die Musik Johann Sebastian Bachs. BJ 1987, S. 113-150 Don L. Smithers: Die Verwendung der Blechblasinstrumente bei J.S. Bach unter besonderer Berücksichtigung der Tromba da tirarsi: kritische Anmerkungen zum gleichnamigen Aufsatz von Thomas G. MacCracken. BJ 1990, S. 37–51
description: Bach-Jahrbuch, Bd. 78 (1992)
Provably efficient machine learning for quantum many-body problems
Creators: name: Huang, Hsin-Yuan
name: Kueng, Richard
name: Torlai, Giacomo
name: Albert, Victor V.
name: Preskill, John
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Information Theory (cs.IT)
subject: Machine Learning (cs.LG)
subject: FOS: Physical sciences
subject: FOS: Computer and information sciences

description: Classical machine learning (ML) provides a potentially powerful approach to solving challenging quantum many-body problems in physics and chemistry. However, the advantages of ML over more traditional methods have not been firmly established. In this work, we prove that classical ML algorithms can efficiently predict ground state properties of gapped Hamiltonians in finite spatial dimensions, after learning from data obtained by measuring other Hamiltonians in the same quantum phase of matter. In contrast, under widely accepted complexity theory assumptions, classical algorithms that do not learn from data cannot achieve the same guarantee. We also prove that classical ML algorithms can efficiently classify a wide range of quantum phases of matter. Our arguments are based on the concept of a classical shadow, a succinct classical description of a many-body quantum state that can be constructed in feasible quantum experiments and be used to predict many properties of the state. Extensive numerical experiments corroborate our theoretical results in a variety of scenarios, including Rydberg atom systems, 2D random Heisenberg models, symmetry-protected topological phases, and topologically ordered phases.
description: 10 pages, 13 figures + 60-page appendix; v4: Fixed a minor formatting issue; open-source code available at https://github.com/hsinyuan-huang/provable-ml-quantum
Ring transformation reactions of 4-hydroxy-3-nitro-6-phenyl-6H-pyrano[3,2-c]quinoline-2,5-dione and antioxidant activity
Creators: name: Abdel-Kader, Dalia
name: Talaat, Nancy
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: Biotechnology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Plant Biology
subject: FOS: Biological sciences

description: 4-Hydroxy-3-nitro-6-phenyl-6H-pyrano[3,2-c]quinoline-2,5-dione was reacted with some 1,2-binucleophiles, such as hydrazine, phenylhydrazine, and hydroxylamine hydrochloride affording the interesting pyrazolyl and isoxazolylquinolinones. Nucleophilic reactions of 3-nitropyranoquinolinone with different 1,4-binucleophiles, leading to a variety of novel diazepinyl, oxazepinyl, and thiadiazepinylquinolinone derivatives, were described. The structure of compounds was proved by elemental analysis and spectral data. Selected products were screened for their antioxidant activity and showed higher radical scavenging abilities.
Cosmic ray acceleration at perpendicular shocks in supernova remnants
Creators: name: Ferrand, Gilles
name: Danos, Rebecca J.
name: Shalchi, Andreas
name: Safi-Harb, Samar
name: Edmon, Paul
name: Mendygral, Peter
Publisher: name: arXiv
Year: 2014
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Supernova remnants (SNRs) are believed to accelerate particles up to high energies through the mechanism of diffusive shock acceleration (DSA). Except for direct plasma simulations, all modeling efforts must rely on a given form of the diffusion coefficient, a key parameter that embodies the interactions of energetic charged particles with the magnetic turbulence. The so-called Bohm limit is commonly employed. In this paper we revisit the question of acceleration at perpendicular shocks, by employing a realistic model of perpendicular diffusion. Our coefficient reduces to a power-law in momentum for low momenta (of index $α$), but becomes independent of the particle momentum at high momenta (reaching a constant value $κ_{\infty}$ above some characteristic momentum $p_{\rm c}$). We first provide simple analytical expressions of the maximum momentum that can be reached at a given time with this coefficient. Then we perform time-dependent numerical simulations to investigate the shape of the particle distribution that can be obtained when the particle pressure back-reacts on the flow. We observe that, for a given index $α$ and injection level, the shock modifications are similar for different possible values of $p_{\rm c}$, whereas the particle spectra differ markedly. Of particular interest, low values of $p_{\rm c}$ tend to remove the concavity once thought to be typical of non-linear DSA, and result in steep spectra, as required by recent high-energy observations of Galactic SNRs.
description: Accepted for publication in ApJ
Performance Evaluation of Parallel Sortings on the Supercomputer Fugaku
Creators: name: Tokuue, Tomoyuki
name: Ishiyama, Tomoaki
Publisher: name: arXiv
Year: 2023
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: Numerical Analysis (math.NA)
subject: Performance (cs.PF)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Sorting is one of the most basic algorithms, and developing highly parallel sorting programs is becoming increasingly important in high-performance computing because the number of CPU cores per node in modern supercomputers tends to increase. In this study, we have implemented two multi-threaded sorting algorithms based on samplesort and compared their performance on the supercomputer Fugaku. The first algorithm divides an input sequence into multiple blocks, sorts each block, and then selects pivots by sampling from each block at regular intervals. Each block is then partitioned using the pivots, and partitions in different blocks are merged into a single sorted sequence. The second algorithm differs from the first one in only selecting pivots, where the binary search is used to select pivots such that the number of elements in each partition is equal. We compare the performance of the two algorithms with different sequential sorting and multiway merging algorithms. We demonstrate that the second algorithm with BlockQuicksort (a quicksort accelerated by reducing conditional branches) for sequential sorting and the selection tree for merging shows consistently high speed and high parallel efficiency for various input data types and data sizes.
description: 7 pages, 6 figures, accepted by Journal of Information Processing
Design factors of intravascular dual frequency transducers for super-harmonic contrast imaging and acoustic angiography
Creators: name: Martin, K Heath
name: Shung, K Kirk
name: Dayton, Paul A
name: Jiang, Xiaoning
name: Ma, Jianguo
name: Li, Yang
name: Zhou, Qifa
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Imaging of coronary vasa vasorum may lead to assessment of the vulnerable plaque development in diagnosis of atherosclerosis diseases. Dual frequency transducers capable of detection of microbubble super-harmonics have shown promise as a new contrast-enhanced intravascular ultrasound (CE-IVUS) platform with the capability of vasa vasorum imaging. Contrast-to-tissue ratio (CTR) in CE-IVUS imaging can be closely associated with the low frequency transmitter performance. In this paper, transducer designs encompassing different transducer layouts, transmitting frequencies, and transducer materials are compared for optimization of imaging performance. In the layout selection, the stacked configuration showed superior super-harmonic imaging compared with the interleaved configuration. In the transmitter frequency selection, a decrease in frequency from 6.5 MHz to 5 MHz resulted in an increase of CTR from 15 dB to 22 dB when receiving frequency was kept constant at 30 MHz. In the material selection, the dual frequency transducer with the lead magnesium niobate-lead titanate (PMN-PT) 1-3 composite transmitter yielded higher axial resolution compared to single crystal transmitters (70 μm compared to 150 μm pulse length). These comparisons provide guidelines for design of intravascular acoustic angiography transducers.
Glucose as an eco-friendly reducing agent for a one-pot multicomponent synthesis of quinoxalines
Creators: name: Gorle, Simhachalam
name: Sekhar, V. N. Chandra
name: Rao, L. Vaikunta
name: Rao, K. Raghavendra
name: Akula, Raghunadh
Publisher: name: Taylor & Francis
Year: 2023
Subjects: subject: Biochemistry
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: 69999 Biological Sciences not elsewhere classified
subject: 110309 Infectious Diseases
subject: FOS: Health sciences

description: An efficient and scalable one-pot multicomponent process is developed for the synthesis of quinoxalines by using D-glucose as a clean, renewable and an eco-friendly reductant in an alkaline aqueous medium. This protocol eliminates the nitro reduction by using pyrophoric metal catalysts like Pd, Ni, Zn, etc., and cyclization as separate steps for the synthesis of quinoxalines. Gram scale experiments and further substrate scope of the reaction have also been well demonstrated.
Schmieder, Wolfgang (Hg.): [...] Bach-Werke-Verzeichnis (BWV), 2. üa. u. erw. Aufl. Wiesbaden 1990
Creators: name: Schulze, Hans-Joachim
Publisher: name: Bach-Jahrbuch
Year: 2018

description: Bach-Jahrbuch, Bd. 78 (1992)
Investigating the structure of gluon fluctuations in the proton with incoherent diffraction at HERA
Creators: name: Kumar, Arjun
name: Toll, Tobias
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Impact parameter dependent dipole models are ideal tools for investigating the spatial structure of the proton. We investigate the incoherent $ep$ cross section in exclusive $J/ψ$ photoproduction as measured by HERA, and find that as $|t|$ increases, the models need several levels of the substructure of gluon density fluctuations in order to describe the measured data well. In lieu of a perturbative description, we add this substructure by hand. This substructure is modelled as hotspots within hotspots. This enables us to describe measurements for $|t|> 1$~GeV$^2$, which is necessary for describing any observable which integrates over the $t$-spectrum, such as the rapidity or $W_{γp}$. We find that three levels of proton substructure are adequate for a good description of all available $ep$ data up to $|t|=30~$GeV$^2$. We note that the gluonic density fluctuation structure follows a scaling behaviour, such that the logarithms of the number of hotspots and their size fall on a line, effectively reducing the available parameter space of the model. Our findings systematically constrain and provide a benchmark for the development of a perturbative model of spatial gluon fluctuations in nucleons.
description: 10 pages, 9 figures
Stabilization of Ab Initio Molecular Dynamics Simulations at Large Time Steps
Creators: name: Tsuchida, Eiji
Publisher: name: arXiv
Year: 2014
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The Verlet method is still widely used to integrate the equations of motion in ab initio molecular dynamics simulations. We show that the stability limit of the Verlet method may be significantly increased by setting an upper limit on the kinetic energy of each atom with only a small loss in accuracy. The validity of this approach is demonstrated for molten lithium fluoride.
description: 9 pages, 3 figures
Relativistic correction of the Coulomb interaction in the local density approximation for energies and radii in doubly-magic nuclei
Creators: name: Naito, Tomoya
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Effects of the relativistic correction of the Coulomb interaction on doubly-magic nuclei are discussed with Skyrme Hartree--Fock calculations. The relativistic correction is treated by using the local density approximation. It is found that the correction to the total energy is about $ 2.4 \, \mathrm{MeV} $ for $ {}^{208} \mathrm{Pb} $, while proton and neutron radii do not change significantly. This difference is larger than the difference of the Coulomb exchange (Fock) energy calculated with the local density (Hartree--Fock--Slater) approximation and that with the exact treatment and the neutron finite-size effect. Effects of the correction are also compared to the correction due to the vacuum polarization. It is shown that the two contributions to the total energy are comparable in light nuclei, but the latter dominates in heavy nuclei, while the contribution of the relativistic correction to the total energy is non-negligible compared to the target accuracy of the DFT calculation.
description: 19 pages, 2 figures, 4 tables
Optimization of multi-pulse sequences for nonlinear contrast agent imaging using a cMUT array
Creators: name: Novell, Anthony
name: Arena, Christopher B
name: Dayton, Paul A
name: Kasoji, Sandeep
Publisher: name: The University of North Carolina at Chapel Hill University Libraries
Year: 2015

description: Capacitive micromachined ultrasonic transducer (cMUT) technology provides advantages such as wide frequency bandwidth, which can be exploited for contrast agent imaging. Nevertheless, the efficiency of traditional multi-pulse imaging schemes, such as pulse inversion (PI), remains limited because of the intrinsic nonlinear character of cMUTs. Recently, a new contrast imaging sequence, called bias voltage modulation sequence (BVM), had been specifically developed for cMUTs to suppress their unwanted nonlinear behavior. In this study, we propose to optimize contrast agent detection by combining the BVM sequence with PI and/or chirp reversal (CR). An aqueous dispersion of lipid encapsulated microbubbles was exposed to several combinations of multi-pulse imaging sequences. Approaches were evaluated in vitro using 9 inter-connected elements of a cMUT linear array (excitation frequency of 4 MHz; peak negative pressure of 100 kPa). For sequences using chirp excitations, a specific compression filter was designed to compress and extract several nonlinear components from the received microbubble responses. A satisfactory cancellation of the nonlinear signal from the source is achieved when BVM is combined with PI and CR. In comparison with PI and CR imaging modes alone, using sequences incorporating BVM increases the contrast-to-tissue ratio by 10.0 dB and 4.6 dB, respectively. Furthermore, the combination of BVM with CR and PI results in a significant increase of the contrast-to-noise ratio (+29 dB). This enhancement is attributed to the use of chirps as excitation signals and the improved preservation of several nonlinear components contained within the contrast agent response.
Marx, Hans Joachim (Hg.): Carl Philipp Emanuel Bach und die europäische Musikkultur. [...] Bericht über das internationale Symposium [...] Hamburg [...] 1988. Göttingen 1990
Creators: name: Schulze, Hans-Joachim
Publisher: name: Bach-Jahrbuch
Year: 2018

description: Bach-Jahrbuch, Bd. 78 (1992)
Classical fully-packed loop model with attractive interactions on the square lattice
Creators: name: Dabholkar, Bhupen
name: Ran, Xiaoxue
name: Rong, Junchen
name: Yan, Zheng
name: Sreejith, G. J.
name: Meng, Zi Yang
name: Alet, Fabien
Publisher: name: arXiv
Year: 2023
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We study a classical model of fully-packed loops on the square lattice, which interact through attractive loop segment interactions between opposite sides of plaquettes. This study is motivated by effective models of interacting quantum matter arising in frustrated magnets or Rydberg atom arrays, for which loop degrees of freedom appear at low energy. Through a combination of Monte Carlo simulations and an effective height field theory, we find that the critical point known to occur at infinite temperature gives rise to a high-temperature critical phase with floating exponents. At lower temperature, the system transitions via a Kosterlitz-Thouless phase transition to a nematic phase where lattice rotation symmetry is broken. We discuss consequences for the phase diagram of the quantum loop model on the same lattice.
description: 11 pages, 9 figures