cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Nanomechanical sensing using spins in diamond
Creators: name: Barson, Michael S. J.
name: Peddibhotla, Phani
name: Ovartchaiyapong, Preeti
name: Ganesan, Kumar
name: Taylor, Richard L.
name: Gebert, Matthew
name: Mielens, Zoe
name: Koslowski, Berndt
name: Simpson, David A.
name: McGuinness, Liam P.
name: McCallum, Jeffrey
name: Prawer, Steven
name: Onoda, Shinobu
name: Ohshima, Takeshi
name: Jayich, Ania C. Bleszynski
name: Jelezko, Fedor
name: Manson, Neil B.
name: Doherty, Marcus W.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Nanomechanical sensors and quantum nanosensors are two rapidly developing technologies that have diverse interdisciplinary applications in biological and chemical analysis and microscopy. For example, nanomechanical sensors based upon nanoelectromechanical systems (NEMS) have demonstrated chip-scale mass spectrometry capable of detecting single macromolecules, such as proteins. Quantum nanosensors based upon electron spins of negatively-charged nitrogen-vacancy (NV) centers in diamond have demonstrated diverse modes of nanometrology, including single molecule magnetic resonance spectroscopy. Here, we report the first step towards combining these two complementary technologies in the form of diamond nanomechanical structures containing NV centers. We establish the principles for nanomechanical sensing using such nano-spin-mechanical sensors (NSMS) and assess their potential for mass spectrometry and force microscopy. We predict that NSMS are able to provide unprecedented AC force images of cellular biomechanics and to, not only detect the mass of a single macromolecule, but also image its distribution. When combined with the other nanometrology modes of the NV center, NSMS potentially offer unparalleled analytical power at the nanoscale.
description: Errors in the stress susceptibility parameters present in the original arXiv version have been corrected
Simplified dark matter models with two Higgs doublets: I. Pseudoscalar mediators
Creators: name: Bauer, Martin
name: Haisch, Ulrich
name: Kahlhoefer, Felix
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study a new class of renormalisable simplified models for dark matter searches at the LHC that are based on two Higgs doublet models with an additional pseudoscalar mediator. In contrast to the spin-0 simplified models employed in analyses of Run I data these models are self-consistent, unitary and bounds from Higgs physics typically pose no constraints. Predictions for various missing transverse energy ($E_{T, \rm miss}$) searches are discussed and the reach of the 13 TeV LHC is explored. It is found that the proposed models provide a rich spectrum of complementary observables that lead to non-trivial constraints. We emphasise in this context the sensitivity of the $t\bar t + E_{T, \rm miss}$, mono-$Z$ and mono-Higgs channels, which yield stronger limits than mono-jet searches in large parts of the parameter space. Constraints from spin-0 resonance searches, electroweak precision measurements and flavour observables are also derived and shown to provide further important handles to constraint and to test the considered dark matter models.
description: 36 pages, 15 figures; v3: matches published version
Parallelized Kalman-Filter-Based Reconstruction of Particle Tracks on Many-Core Processors and GPUs
Creators: name: Cerati, Giuseppe
name: Elmer, Peter
name: Krutelyov, Slava
name: Lantz, Steven
name: Lefebvre, Matthieu
name: Masciovecchio, Mario
name: McDermott, Kevin
name: Riley, Daniel
name: Tadel, Matevž
name: Wittich, Peter
name: Würthwein, Frank
name: Yagil, Avi
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computational Physics (physics.comp-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: For over a decade now, physical and energy constraints have limited clock speed improvements in commodity microprocessors. Instead, chipmakers have been pushed into producing lower-power, multi-core processors such as GPGPU, ARM and Intel MIC. Broad-based efforts from manufacturers and developers have been devoted to making these processors user-friendly enough to perform general computations. However, extracting performance from a larger number of cores, as well as specialized vector or SIMD units, requires special care in algorithm design and code optimization. One of the most computationally challenging problems in high-energy particle experiments is finding and fitting the charged-particle tracks during event reconstruction. This is expected to become by far the dominant problem in the High-Luminosity Large Hadron Collider (HL-LHC), for example. Today the most common track finding methods are those based on the Kalman filter. Experience with Kalman techniques on real tracking detector systems has shown that they are robust and provide high physics performance. This is why they are currently in use at the LHC, both in the trigger and offline. Previously we reported on the significant parallel speedups that resulted from our investigations to adapt Kalman filters to track fitting and track building on Intel Xeon and Xeon Phi. Here, we discuss our progresses toward the understanding of these processors and the new developments to port Kalman filter to NVIDIA GPUs.
description: Submitted to proceedings of Connecting The Dots 2017 (CTD2017), Orsay. arXiv admin note: substantial text overlap with arXiv:1605.05508
COMPARATIVE STUDY OF WATER CONSUMPTION PATTERNS IN BRAZIL AND CANADA
Creators: name: Clara, Beatriz González
name: Luis, Alejandro Romero
name: Sofia, Isabel Torres
Publisher: name: CARSON JOURNAL
Year: 2024
Subjects: Sustainable consumption, water behavior, contextual variables, comparative analysis, environmental awareness

description: Sustainable consumption of natural resources, particularly water, has gained prominence in global governmental agendas. Water, vital for food supply, hygiene, environmental equilibrium, and material asset maintenance, necessitates responsible management to ensure its availability for future generations. This underscores the need to comprehend consumer behaviors related to water, promoting sustainable practices. Motivational factors driving sustainable behavior adoption have been a focus of consumer behavior research. Contextual variables, encompassing social, economic, legal, political, and natural conditions, play pivotal roles in this context. Comparative studies exploring these factors in sustainable behavior adoption have gained significance, shedding light on how contextual designs stimulate sustainable behavior. Research has highlighted the importance of contextual influences on behavior intention and environmental awareness, emphasizing the role of norms, structural factors, environmental knowledge, and degrees of collectivity and individuality in driving sustainable behavior adaptation. This study contributes to the growing body of research in sustainable consumption by examining contextual variables and their impact on water-related consumer behaviors. Through a comparative analysis, it seeks to identify contextual designs that facilitate sustainable behavior adoption and shed light on the influence of norms, environmental knowledge, and collectivity
The ALMA Frontier Fields Survey III: 1.1 mm Emission Line Identifications in Abell 2744, MACSJ0416.1-2403, MACSJ1149.5+2223, Abell 370, and Abell S1063
Creators: name: González-López, J.
name: Bauer, F. E.
name: Aravena, M.
name: Laporte, N.
name: Bradley, L.
name: Carrasco, M.
name: Carvajal, R.
name: Demarco, R.
name: Infante, L.
name: Kneissl, R.
name: Koekemoer, A. M.
name: Arancibia, A. M. Muñoz
name: Troncoso, P.
name: Villard, E.
name: Zitrin, A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Most sub-mm emission line studies of galaxies to date have targeted sources with known redshifts where the frequencies of the lines are well constrained. Recent blind line scans circumvent the spectroscopic redshift requirement, which could represent a selection bias. Our aim is to detect emission lines present in continuum oriented observations. The detection of such lines provides spectroscopic redshift and yields properties of the galaxies. We perform a search for emission lines in the ALMA observations of five Frontier Fields clusters and assess the reliability of our detection by associating line candidates with detected galaxies in deep near-infrared imaging. We find 26 significant emission lines candidates, with observed line fluxes between 0.2-4.6 Jy km s$^{-1}$ and velocity dispersions (FWHM) of 25-600 km s$^{-1}$. Nine of these candidates lie nearby to near-infrared sources, boosting their reliability; in six cases the observed line frequency and strength are consistent with expectations given the photometric redshift and properties of the galaxy counterparts. We present redshift identifications, magnifications and molecular gas estimates for the galaxies with identified lines. We show that two of these candidates likely originate from starburst galaxies, one of which is a jellyfish galaxy, while another two are consistent with being main sequence galaxies based in their depletion times. This work highlights the degree to which serendipitous emission lines can be discovered in large mosaic continuum observations when deep ancillary data are available. The low number of high-significance line detections, however, confirms that such surveys are not as optimal as blind line scans. We stress that Monte Carlo simulations should be used to assess the line detections significances, since using the negative noise suffers from stochasticity and incurs larger uncertainties.
description: new version accepted for publication in A&A
Standard Model Mass Spectrum in Inflationary Universe
Creators: name: Chen, Xingang
name: Wang, Yi
name: Xianyu, Zhong-Zhi
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We work out the Standard Model (SM) mass spectrum during inflation with quantum corrections, and explore its observable consequences in the squeezed limit of non-Gaussianity. Both non-Higgs and Higgs inflation models are studied in detail. We also illustrate how some inflationary loop diagrams can be computed neatly by Wick-rotating the inflation background to Euclidean signature and by dimensional regularization.
description: 62 pages, JHEP accepted version
$B\toππ$ Form Factors from Light-Cone Sum Rules with $B$-meson Distribution Amplitudes
Creators: name: Cheng, Shan
name: Khodjamirian, Alexander
name: Virto, Javier
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We study $B\toππ$ form factors using QCD light-cone sum rules with $B$-meson distribution amplitudes. These form factors describe the semileptonic decay $B\to ππ\ell\barν_{\ell}$, and constitute an essential input in $B\to ππ\ell^+\ell^-$ and $B\to πππ$ decays. We employ the correlation functions where a dipion isospin-one state is interpolated by the vector light-quark current. We obtain sum rules where convolutions of the $P$-wave $\bar{B}^0\to π^+π^0$ form factors with the time-like pion vector form factor are related to universal $B$-meson distribution amplitudes. These sum rules are valid in the kinematic regime where the dipion state has a large energy and a low invariant mass, and reproduce analytically the known light-cone sum rules for $B\to ρ$ form factors in the limit of $ρ$-dominance with zero width, thus providing a systematics for so-far-unaccounted corrections to $B\toρ$ transitions. Using data for the pion vector form factor, we estimate finite width-effects and the contribution of excited $ρ$-resonances to the $B\toππ$ form factors. We find that these contributions amount up to $\sim 20\%$ in the small dipion mass region where they can be effectively regarded as a nonresonant ($P$-wave) background to the $B\toρ$ transition.
description: 28 pages, 3 figures. A few comments added. Version published in JHEP
Machine Learning on Sequential Data Using a Recurrent Weighted Average
Creators: name: Ostmeyer, Jared
name: Cowell, Lindsay
Publisher: name: arXiv
Year: 2017
Subjects: subject: Machine Learning (stat.ML)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Recurrent Neural Networks (RNN) are a type of statistical model designed to handle sequential data. The model reads a sequence one symbol at a time. Each symbol is processed based on information collected from the previous symbols. With existing RNN architectures, each symbol is processed using only information from the previous processing step. To overcome this limitation, we propose a new kind of RNN model that computes a recurrent weighted average (RWA) over every past processing step. Because the RWA can be computed as a running average, the computational overhead scales like that of any other RNN architecture. The approach essentially reformulates the attention mechanism into a stand-alone model. The performance of the RWA model is assessed on the variable copy problem, the adding problem, classification of artificial grammar, classification of sequences by length, and classification of the MNIST images (where the pixels are read sequentially one at a time). On almost every task, the RWA model is found to outperform a standard LSTM model.
Quantum q-Field Theory: q-Schrödinger and q-Klein-Gordon Fields
Creators: name: Plastino, A.
name: Rocca, M. C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We show how to deal with the generalized q-Schrödinger and q-Klein-Gordon fields in a variety of scenarios. These q-fields are meaningful at very high energies (TeVs) for for $q=1.15$, high ones (GeVs) for $q=1.001$, and low energies (MeVs)for $q=1.000001$ [Nucl. Phys. A {\bf 948} (2016) 19, Nucl. Phys. A {\bf 955} (2016) 16]. We develop here the quantum field theory (QFT) for the q-Schrödinger and q-Klein-Gordon fields, showing that both reduce to the customary Schrödinger and Klein-Gordon QFTs for q close to unity. Further, we analyze the q-Klein-Gordon field for $2q-1=n$ (n integer $\ge 2$) and analytically compute the self-energy and the propagator up to second order.
description: Text has changed. Accepted for publication in Europhysics Letters. August 8, 2017
Quasirationality and aspherical (pro-$p$)presentations
Creators: name: Mikhovich, Andrey
Publisher: name: arXiv
Year: 2017
Subjects: subject: Group Theory (math.GR)
subject: Algebraic Topology (math.AT)
subject: K-Theory and Homology (math.KT)
subject: FOS: Mathematics

description: Quasirational (pro-$p$)presentations are studied. The difference between aspherical and quasirational presentations sheds some light on the Whitehead's conjecture. We confirm expectations O.V. Melnikov on existence of a proper class of presentations.
description: in Russian
Airy-averaged gradient corrections for two-dimensional fermion gases
Creators: name: Trappe, Martin-Isbjörn
name: Len, Yink Loong
name: Ng, Hui Khoon
name: Englert, Berthold-Georg
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Building on the discussion in PRA 93, 042510 (2016), we present a systematic derivation of gradient corrections to the kinetic-energy functional and the one-particle density, in particular for two-dimensional systems. We derive the leading gradient corrections from a semiclassical expansion based on Wigner's phase space formalism and demonstrate that the semiclassical kinetic-energy density functional at zero temperature cannot be evaluated unambiguously. In contrast, a density-potential functional description that effectively incorporates interactions provides unambiguous gradient corrections. Employing an averaging procedure that involves Airy functions, thereby partially resumming higher-order gradient corrections, we facilitate a smooth transition of the particle density into the classically forbidden region of arbitrary smooth potentials. We find excellent agreement of the semiclassical Airy-averaged particle densities with the exact densities for very low but finite temperatures, illustrated for a Fermi gas with harmonic potential energy. We furthermore provide criteria for the applicability of the semiclassical expansions at low temperatures. Finally, we derive a well-behaved ground-state kinetic-energy functional, which improves on the Thomas-Fermi approximation.
description: 24 pages, 8 figures. Changes to version 1: layout modified, footnotes 1 & 12 added, one paragraph added on page 7
Core structure of two-dimensional Fermi gas vortices in the BEC-BCS crossover region
Creators: name: Madeira, Lucas
name: Gandolfi, Stefano
name: Schmidt, Kevin E.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We report $T=0$ diffusion Monte Carlo results for the ground-state and vortex excitation of unpolarized spin-1/2 fermions in a two-dimensional disk. We investigate how vortex core structure properties behave over the BEC-BCS crossover. We calculate the vortex excitation energy, density profiles, and vortex core properties related to the current. We find a density suppression at the vortex core on the BCS side of the crossover, and a depleted core on the BEC limit. Size-effect dependencies in the disk geometry were carefully studied.
description: 10 pages, 7 figures
High resolution ALMA observation of the $^{12}$CO(3-2) and 350 GHz continuum emissions of the debris disc of 49 Ceti
Creators: name: Nhung, P. T.
name: Hoai, D. T.
name: Tuan-Anh, P.
name: Diep, P. N.
name: Phuong, N. T.
name: Thao, N. T.
name: Darriulat, P.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present high resolution ALMA observations of the CO(3-2) and 350 GHz continuum emissions of the debris disc of 49 Ceti, known to be particularly rich in molecular gas in spite of its age. The main new results are: i) both CO and dust discs share a same position angle and a same inclination but the gas disc is more homogeneous, more central and thinner than the dust disc; ii) evidence is obtained for a significant deficit of observed CO(3-2) emission at Doppler velocities differing from the star systemic velocity by less than 1 \kms; iii) gas velocities are accurately measured and found Keplerian over a broad range of disc radii; iv) the observed CO(3-2) line width is dominated by Keplerian shear and upper limits are obtained to the intrinsic line width. Simple phenomenological models of both CO(3-2) and \mbox{350 GHz} continuum emissions are presented, requiring the use of only very few parameters. The results are discussed in the frame of currently favoured models.
description: 15 pages, 11 figures, accepted for publication in MNRAS
Controlling the Error on Target Motion through Real-time Mesh Adaptation: Applications to Deep Brain Stimulation
Creators: name: Bui, Huu Phuoc
name: Tomar, Satyendra
name: Courtecuisse, Hadrien
name: Audette, Michel
name: Cotin, Stéphane
name: Bordas, Stéphane P. A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Computational Engineering, Finance, and Science (cs.CE)
subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Computer and information sciences
subject: FOS: Biological sciences

description: We present an error-controlled mesh refinement procedure for needle insertion simulation and apply it to the simulation of electrode implantation for deep brain stimulation, including brain shift. Our approach enables to control the error in the computation of the displacement and stress fields around the needle tip and needle shaft by suitably refining the mesh, whilst maintaining a coarser mesh in other parts of the domain. We demonstrate through academic and practical examples that our approach increases the accuracy of the displacement and stress fields around the needle without increasing the computational expense. This enables real-time simulations. The proposed methodology has direct implications to increase the accuracy and control the computational expense of the simulation of percutaneous procedures such as biopsy, brachytherapy, regional anesthesia, or cryotherapy and can be essential to the development of robotic guidance.
description: 21 pages, 14 figures
Cosmic Microwave Background as a thermal gas of SU(2) photons: Implications for the high-z cosmological model and the value of $H_0$
Creators: name: Hahn, Steffen
name: Hofmann, Ralf
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Presently, we are facing a 3$σ$ tension in the most basic cosmological parameter -- the Hubble constant $H_0$. This tension arises when fitting the Lambda-cold-dark-matter model ($Λ$CDM) to the high-precision temperature-temperature (TT) power spectrum of the Cosmic Microwave Background (CMB) and to local cosmological observations. We propose a resolution of this problem by postulating that the thermal photon gas of the CMB obeys an SU(2) rather than U(1) gauge principle, suggesting a high-$z$ cosmological model which is void of dark matter. Observationally, we rely on precise low-frequency intensity measurements in the CMB spectrum and on a recent model independent (low-$z$) extraction of the relation between the comoving sound horizon $r_s$ at the end of the baryon drag epoch and $H_0$ ($r_s H_0 = \text{const}$). We point out that the commonly employed condition for baryon-velocity freeze-out is imprecise, judged by a careful inspection of the formal solution to the associated Euler equation. As a consequence, the above mentioned 3$σ$ tension actually transforms into a 5$σ$ discrepancy. To make contact with successful low-$z$ $Λ$CDM cosmology we propose an interpolation based on percolated/depercolated vortices of a Planck-scale axion condensate. For a first consistency test of such an all-$z$ model we compute the angular scale of the sound horizon at photon decoupling.
description: 16 pp, 5 figs; v2: references added and extended text
Hidden correlations entailed by q-non additivity render the q-monoatomic gas highly non trivial
Creators: name: Plastino, A.
name: Rocca, M. C.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: It ts known that Tsallis' q-non-additivity entails hidden correlations. It has also been shown that even for a monoatomic gas, both the q-partition function $Z$ and the mean energy $$ diverge and, in particular, exhibit poles for certain values of the Tsallis non additivity parameter $q$. This happens because $Z$ and $$ both depend on a $Γ$-function. This $Γ$, in turn, depends upon the spatial dimension $ν$. We encounter three different regimes according to the argument $A$ of the $Γ$-function. (1) $A>0$, (2) $A<0$ and $Γ>0$ outside the poles. (3) $A$ displays poles and the physics is obtained via dimensional regularization. In cases (2) and (3) one discovers gravitational effects and quartets of particles. Moreover, bound states and gravitational effects emerge as a consequence of the hidden q-correlations.
description: Text has changed. Accepted for publication in Physica A, August 2, 2017
Kinetic theory of dark solitons with tunable friction
Creators: name: Hurst, Hilary M.
name: Efimkin, Dmitry K.
name: Spielman, I. B.
name: Galitski, Victor
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We study controllable friction in a system consisting of a dark soliton in a one-dimensional Bose-Einstein condensate coupled to a non-interacting Fermi gas. The fermions act as impurity atoms, not part of the original condensate, that scatter off of the soliton. We study semi-classical dynamics of the dark soliton, a particle-like object with negative mass, and calculate its friction coefficient. Surprisingly, it depends periodically on the ratio of interspecies (impurity-condensate) to intraspecies (condensate-condensate) interaction strengths. By tuning this ratio, one can access a regime where the friction coefficient vanishes. We develop a general theory of stochastic dynamics for negative mass objects and find that their dynamics are drastically different from their positive mass counterparts - they do not undergo Brownian motion. From the exact phase space probability distribution function (i.e. in position and velocity), we find that both the trajectory and lifetime of the soliton are altered by friction, and the soliton can only undergo Brownian motion in the presence of friction and a confining potential. These results agree qualitatively with experimental observations by Aycock, et. al. (PNAS, 2017) in a similar system with bosonic impurity scatterers.
description: 6 figures, 14 pages incl. appendices
Microenvironmental cooperation promotes early spread and bistability of a Warburg-like phenotype
Creators: name: Fernandez-de-Cossio-Diaz, Jorge
name: De Martino, Andrea
name: Mulet, Roberto
Publisher: name: arXiv
Year: 2017
Subjects: subject: Molecular Networks (q-bio.MN)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Biological Physics (physics.bio-ph)
subject: Tissues and Organs (q-bio.TO)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: We introduce an in silico model for the initial spread of an aberrant phenotype with Warburg-like overflow metabolism within a healthy homeostatic tissue in contact with a nutrient reservoir (the blood), aimed at characterizing the role of the microenvironment for aberrant growth. Accounting for cellular metabolic activity, competition for nutrients, spatial diffusion and their feedbacks on aberrant replication and death rates, we obtain a phase portrait where distinct asymptotic whole-tissue states are found upon varying the tissue-blood turnover rate and the level of blood-borne primary nutrient. Over a broad range of parameters, the spreading dynamics is bistable as random fluctuations can impact the final state of the tissue. Such a behaviour turns out to be linked to the re-cycling of overflow products by non-aberrant cells. Quantitative insight on the overall emerging picture is provided by a spatially homogeneous version of the model.
description: 14 pages
How Do Developers Structure Unit Test Cases? An Empirical Study from the "AAA" Perspective
Creators: name: Wei, Chenhao
name: Xiao, Lu
name: Yu, Tingting
name: Wong, Sunny
name: Clune, Abigail
Publisher: name: arXiv
Year: 2024
Subjects: subject: Software Engineering (cs.SE)
subject: FOS: Computer and information sciences
subject: D.2.5

description: The AAA pattern, i.e. arrange, act, and assert, provides a unified structure for unit test cases, which benefits comprehension and maintenance. However, there is little understanding regarding whether and how common real-life developers structure unit test cases following AAA in practice. In particular, are there recurring anti-patterns that deviate from the AAA structure and merit refactoring? And, if test cases follow the AAA structure, could they contain design flaws in the A blocks? If we propose refactoring to fix the design of test cases following the AAA, how do developers receive the proposals? Do they favor refactoring? If not, what are their considerations? This study presents an empirical study on 435 real-life unit test cases randomly selected from four open-source projects. Overall, the majority (71.5%) of test cases follow the AAA structure. And, we observed three recurring anti-patterns that deviate from the AAA structure, as well as four design flaws that may reside inside of the A blocks. Each issue type has its drawbacks and merits corresponding refactoring resolutions. We sent a total of 18 refactoring proposals as issue tickets for fixing these problems. We received 78% positive feedback favoring the refactoring. From the rejections, we learned that return-on-investment is a key consideration for developers. The findings provide insights for practitioners to structure unit test cases with AAA in mind, and for researchers to develop related techniques for enforcing AAA in test cases.
Hourglass semimetals with nonsymmorphic symmetries in three dimensions
Creators: name: Wang, Luyang
name: Jian, Shao-Kai
name: Yao, Hong
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: It was recently shown that nonsymmorphic space group symmetries can protect novel surface states with hourglass-like dispersions. In this paper, we show that such dispersions can also appear in the bulk of three-dimensional (3D) systems which respect nonsymmorphic symmetries. Specifically, we construct 3D lattice models featuring hourglass-like dispersions in the bulk, which are protected by nonsymmorphic and time-reversal symmetries. We call such systems hourglass semimetals, as they have point or line nodes associated with hourglass-like dispersions. Hourglass nodal lines appear in glide-invariant planes, while hourglass Weyl points can occur on screw-invariant axes. The Weyl points and surface Fermi arcs in hourglass Weyl semimetals are stable against weak perturbations breaking those nonsymmorphic symmetries. Our results may shed light on searching for exotic Weyl semimetals in nonsymmorphic materials.
description: 6 pages, 5 figures + Supplemental Material, published versioin
A sensitive, stable, continuously rotating FFL MPI system for functional imaging of the rat brain
Creators: name: Mattingly, Eli
name: Mason, Erica
name: Herb, Konstantin
name: Śliwiak, Monika
name: Drago, John
name: Graeser, Matthias
name: Wald, Lawrence
Publisher: name: International Journal on Magnetic Particle Imaging
Year: 2022

description: Magnetic particle imaging noninvasively maps the distribution of superparamagnetic iron oxide nanoparticles with high sensitivity. Since the particles are confined to the blood pool within the brain, it may be well-suited for cerebral blood volume (CBV)-based functional neuroimaging with MPI (fMPI). Here, we present a magnetic particle imaging system designed to detect the CBV modulation at the hemodynamic timescale (~5 sec) in rodents. It has the capacity to record sufficiently fast image time-series for several hours continuously. The time-series imaging was achieved with an optimized drive coil that maintains ~0.01% per minute current magnitude stability. An electrical slip ring and rotary union for cooling water allows continuous mechanical rotation of the 2.83 T/m Field-Free Line (FFL) permanent magnets and shift coils. The system achieves a 6.7 ng Fe detection limit (SNR = 5) in a single 5 sec image in the time-series, a spatial resolution of 3.0 mm in a 3 cm diameter field of view. The designs have been made open-source to enable replication of this device. Int. J. Mag. Part. Imag. 8(2), 2022, Article ID: 2212001, DOI: 10.18416/IJMPI.2022.2212001
description: International Journal on Magnetic Particle Imaging, Vol 8 No 2 (2022)
Link colorings and the Goeritz matrix
Creators: name: Traldi, Lorenzo
Publisher: name: arXiv
Year: 2017
Subjects: subject: Geometric Topology (math.GT)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We discuss the connection between colorings of a link diagram and the Goeritz matrix.
description: v1: 16 pages, 6 figures. v2: minor corrections and improvements. 18 pages, 7 figures. v3: 19 pages, 7 figures. v4: 19 pages, 7 figures. Final prepublication version. Further changes may be made before publication in the Journal of Knot Theory and its Ramifications
False Vacuum Decay in Gauge Theory
Creators: name: Endo, Motoi
name: Moroi, Takeo
name: Nojiri, Mihoko M.
name: Shoji, Yutaro
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The decay rate of a false vacuum is studied in gauge theory, paying particular attention to its gauge invariance. Although the decay rate should not depend on the gauge parameter $ξ$ according to the Nielsen identity, the gauge invariance of the result of a perturbative calculation has not been clearly shown. We give a prescription to perform a one-loop calculation of the decay rate, with which a manifestly gauge-invariant expression of the decay rate is obtained. We also discuss the renormalization necessary to make the result finite, and show that the decay rate is independent of the gauge parameter even after the renormalization.
description: 39 pages, 1 figure, typos corrected, reference added
The tilting rate of the Milky Way's disc
Creators: name: Earp, Samuel W. F.
name: Debattista, Victor P.
name: Macciò, Andrea V.
name: Cole, David R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present tilting rates for galaxies comparable to the Milky Way (MW) in a $Λ$ cold dark matter cosmological hydrodynamical simulation, and compare these with the predicted tilting rate detection limit of the {\it Gaia} satellite $0.28\degrees$Gyr$^{-1}$. We first identify galaxies with mass comparable to the MW ($9 \times 10^{11} \le M_{200} \le 1.2 \times 10^{12} \Msun $) and consider the tilting rates between $z=0.3$ and $0$. This sample yields a tilting rate of $7.6\degrees \pm 4.5\degrees$Gyr$^{-1}$. We constrain our sample further to exclude any galaxies that have high stellar accretion during the same time. We still find significant tilting, with an average rate of $6.3\degrees$Gyr$^{-1}$. Both subsamples tilt with rates significantly above {\it Gaia}'s predicted detection limit. We show that our sample of galaxies covers a wide range of environments, including some similar to the MW's. We find galaxies in denser regions tilt with higher rates then galaxies in less dense regions. We also find correlations between the angular misalignment of the hot gas corona, and the tilting rate. {\it Gaia} is likely to be able to directly measure tilting in the MW. Such a detection will provide an important constraint on the environment of the MW, including the rate of gas cooling onto the disc, the shape and orientation of its dark matter halo, and the mass of the Large Magellanic Cloud. Conversely, failure to detect tilting may suggest the MW is in a very quiet configuration.
description: 8 pages, 7 figures, published in MNRAS, updated to match published version
Current and Future Constraints on Primordial Magnetic Fields
Creators: name: Sutton, Dylan R.
name: Feng, Chang
name: Reichardt, Christian L.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present new limits on the amplitude of potential primordial magnetic fields (PMFs) using temperature and polarization measurements of the cosmic microwave background (CMB) from Planck, BICEP2/Keck Array, POLARBEAR, and SPTpol. We reduce twofold the 95% CL upper limit on the CMB anisotropy power due to a nearly-scale-invariant PMF, with an allowed B-mode power at $\ell=1500$ of $D_{\ell=1500}^{BB} < 0.071 μK^2$ for Planck versus $D_{\ell=1500}^{BB} < 0.034 μK^2$ for the combined dataset. We also forecast the expected limits from soon-to-deploy CMB experiments (like SPT-3G, Adv. ACTpol, or the Simons Array) and the proposed CMB-S4 experiment. Future CMB experiments should dramatically reduce the current uncertainties, by one order of magnitude for the near-term experiments and two orders of magnitude for the CMB-S4 experiment. The constraints from CMB-S4 have the potential to rule out much of the parameter space for PMFs.
description: Submitted to ApJ, 10 pages
title: An Assessment of Current Efforts Towards a Circular Economy - The Case of Chemical Recycling with Pyrolysis Processes
Creators: name: Bruch, Felix
Publisher: name: TU Wien
Year: 2023
Subjects: subject: plastic waste
subject: circular economy
subject: chemical recycling
subject: pyrolysis processes

description: The accumulation of plastic waste in recent decades, caused by elevated levels of production and a short period of use in many cases, poses increasingly severe challenges to marine and terrestrial life. Therefore, attempts are being made to identify ways to reduce these quantities in order to counteract the problem. Circular Economy is a buzzword that is often mentioned in this context, under which many activities to extend the service lifetime are subsumed. Pyrolysis processes, as a form of chemical recycling, involve a technique often presented as a poster child and are subject to increased research. Consequently, this thesis will address the following research question in more detail: In an attempt to create a more Circular Economy, what can chemical recycling in the form of pyrolysis offer? To answer this relatively broad question more specifically, two sub-research questions have emerged: (1) What qualifies pyrolysis processes to be classified as circular? and (2) What is holding companies back from pursuing larger-scale implementation of the pyrolysis technology? The first part of the work provides an overview through literature research of the concept of Circular Economy, selected critical aspects of it, as well as an insight into plastic waste management and an in-depth examination of the functioning of chemical recycling in general and pyrolysis processes in particular. Subsequently, in the empirical part, the current implementation status is exploratively recorded with the help of expert interviews, targeted research, and statements from companies in the pyrolysis industry. On the one hand, the result presents a screenshot of the current efforts to bring pyrolysis processes to market and, on the other hand, an overview of the hurdles that still need to be overcome before wide spread implementation is possible. These barriers are divided into five dimensions, namely technological, environmental, legal, economicand logistical. According to the analysis, pyrolysis can be classified as an initiative within the Circular Economy, as it pursues the goal of keeping materials in the loop with clear parallels to the general discourse on the concept. Nevertheless, in practice,the technology remains in its infancy and struggles to deliver on its high expectations.
Tree-level vacuum stability of two-Higgs-doublet models and new constraints on the scalar potential
Creators: name: Xu, Xun-Jie
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The scalar potential of the two-Higgs-doublet model (2HDM) may have more than one local minimum and the usually considered vacuum could be located at one of them that could decay to another. This paper studies the condition that the usually considered vacuum is the global minimum which, combined with the bounded-from-below condition, will stabilize the vacuum at tree-level. We further apply these conditions to a specific 2HDM and obtain new constraints which could be important in phenomenological studies.
description: 12 pages, references added
On $C^1$, $C^2$, and weak type-$(1,1)$ estimates for linear elliptic operators: Part II
Creators: name: Dong, Hongjie
name: Escauriaza, Luis
name: Kim, Seick
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics

description: We extend and improve the results in \cite{DK16}: showing that weak solutions to full elliptic equations in divergence form with zero Dirichlet boundary conditions are continuously differentiable up to the boundary when the leading coefficients have Dini mean oscillation and the lower order coefficients verify certain conditions. Similar results are obtained for non-divergence form equations. We extend the weak type-(1, 1) estimates in \cite{DK16} and \cite{Es94} up to the boundary and derive a Harnack inequality for non-negative adjoint solutions to non-divergence form elliptic equations, when the leading coefficients have Dini mean oscillation.
description: minor correction; accepted in Mathematische Annalen
Geometric Josephson junction
Creators: name: Santos, Fabiano F.
name: Boschi-Filho, Henrique
Publisher: name: arXiv
Year: 2024
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: In this work, we present a gravitational dual to a constriction Josephson junction constructed from the AdS/BCFT correspondence. On the gravity side, we consider a planar AdS-Schwarzschild black hole. Our junction is connected by the boundary $\partialΩ$ with tension $Σ$ on the boundary CFT. This approach lead us to analytical solutions rather than usual numerical methods. Our computations on the gravity side reproduce the standard relation between the current across the junction and the phase difference of the condensate controlled by the tension $Σ$. We also study the maximum current's dependence on the junction's tension and size and reproduce familiar results.
description: 17 pages, 6 figures
Relativistic Chiral Kinetic Theory from Quantum Field Theories
Creators: name: Hidaka, Yoshimasa
name: Pu, Shi
name: Yang, Di-Lun
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The chiral kinetic theory of Weyl fermions with collisions in the presence of weak electric and magnetic fields is derived from quantum field theories. It is found that the side-jump terms in the perturbative solution of Wigner functions play a significant role for the derivation. Moreover, such terms manifest the breaking of Lorentz symmetry for distribution functions. The Lorentz covariance of Wigner functions thus leads to modified Lorentz transformation associated with side-jump phenomena further influenced by background fields and collisions.
description: 6 pages, journal version, accepted by PRD rapid communication
A Floquet formalism for the interaction of magnetically trapped atoms with rf-fields
Creators: name: Chakraborty, A.
name: Mishra, S. R.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A many mode Floquet theory (MMFT) formalism is applied to study the interaction of a polychromatic rf-field with cold atoms trapped in a quadrupole magnetic trap. In this work, the validity of MMFT approach is first established by comparing its results with those of the previously used formalisms for the cases of single and two frequency rf-fields. We have then used the MMFT formalism to calculate the eigen-energies and transition probabilities for atoms in the quadrupole trap and interacting with a polychromatic rf-field. This composite atom-field system has shown some exquisite features such as lattice like periodic variation in the eigen-energies and large two-photon transition probabilities between the atomic states. This work thus predicts the generation of a lattice type atom trapping potential using polychromatic rf-field, which can be controlled by varying the rf-field parameters.
description: 10 Pages, 7 Figures
Development of 3D Printing Multifunctional Materials for Structural Health Monitoring
Creators: name: Maynard, Cole M
Publisher: name: Purdue University Graduate School
Year: 2022
Subjects: Polymers and plastics
Functional materials
Composite and hybrid materials
Electronic device and system performance evaluation, testing and simulation
Electronic sensors
Industrial electronics
Additive manufacturing
Electrical engineering not elsewhere classified
Civil engineering not elsewhere classified
Mechanical engineering not elsewhere classified

description: Multifunctional additive manufacturing has the immense potential of addressing present needs within structural health monitoring by enabling a new additive manufacturing paradigm that redefines what a sensor is, or what sensors should resemble. To achieve this, the properties of printed components must be precisely tailored to meet structure specific and application specific requirements. However due to the limited number of commercially available multifunctional filaments, this research investigates the in-house creation of adaptable piezoresistive multifunctional filaments and their potential within structural health monitoring applications based upon their characterized piezoresistive responses. To do so, a rigid polylactic acid based-filament and a flexible thermoplastic polyurethane based-filament were modified to impart piezoresistive properties using carbon nanofibers. The filaments were produced using different mixing techniques, nanoparticle concentrations, and optimally selected manufacturing parameters from a design of experiments approach. The resulting filaments exhibited consistent resistivity values which were found to be less variable under specific mixing techniques than commercially available multifunctional filaments. This improved consistency was found to be a key factor which held back currently available piezoresistive filaments from fulfilling needs within structural health monitoring. To demonstrate the ability to meet these needs, the piezoresistive responses of three dog-bone shaped sensor sizes were measured under monotonic and cyclic loading conditions for the optimally manufactured filaments. The characterized piezoresistive responses demonstrated high strain sensitivities under both tensile and compressive loads. These piezoresistive sensors demonstrated the greatest sensitivity in tension, where all three sensor sizes exhibited gauge factors over 30. Cyclic loading supported these results and further demonstrated the accuracy and reliability of the printed sensors within SHM applications.
The revival of the Baldwin Effect
Creators: name: Fontanari, José F.
name: Santos, Mauro
Publisher: name: arXiv
Year: 2017
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences

description: The idea that a genetically fixed behavior evolved from the once differential learning ability of individuals that performed the behavior is known as the Baldwin effect. A highly influential paper [Hinton G.E., Nowlan S.J., 1987. How learning can guide evolution. Complex Syst. 1, 495-502] claimed that this effect can be observed in silico, but here we argue that what was actually shown is that the learning ability is easily selected for. Then we demonstrate the Baldwin effect to happen in the in silico scenario by estimating the probability and waiting times for the learned behavior to become innate. Depending on parameter values, we find that learning can increase the chance of fixation of the learned behavior by several orders of magnitude compared with the non-learning situation.