cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Network analysis of the human structural connectome including the brainstem
Creators: name: Salhi, Salma
name: Kora, Youssef
name: Ham, Gisu
name: Haghighi, Hadi Zadeh
name: Simon, Christoph
Publisher: name: arXiv
Year: 2022
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Biological sciences
subject: FOS: Physical sciences

description: The underlying anatomical structure is fundamental to the study of brain networks, but the role of brainstem from a structural perspective is not very well understood. We conduct a computational and graph-theoretical study of the human structural connectome incorporating a variety of subcortical structures including the brainstem. Our computational scheme involves the use of Python DIPY and Nibabel libraries to develop structural connectomes using 100 healthy adult subjects. We then compute degree, eigenvector, and betweenness centralities to identify several highly connected structures and find that the brainstem ranks highest across all examined metrics, a result that holds even when the connectivity matrix is normalized by volume. We also investigated some global topological features in the connectomes, such as the balance of integration and segregation, and found that the domination of the brainstem generally causes networks to become less integrated and segregated. Our results highlight the importance of including the brainstem in structural network analyses.
description: 25 pages, 7 figures
Thermodynamics of the Lévy spin glass
Creators: name: Janzen, K.
name: Engel, A.
name: Mézard, M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We investigate the Lévy glass, a mean-field spin glass model with power-law distributed couplings characterized by a divergent second moment. By combining extensively many small couplings with a spare random backbone of strong bonds the model is intermediate between the Sherrington-Kirkpatrick and the Viana-Bray model. A truncated version where couplings smaller than some threshold $\eps$ are neglected can be studied within the cavity method developed for spin glasses on locally tree-like random graphs. By performing the limit $\eps\to 0$ in a well-defined way we calculate the thermodynamic functions within replica symmetry and determine the de Almeida-Thouless line in the presence of an external magnetic field. Contrary to previous findings we show that there is no replica-symmetric spin glass phase. Moreover we determine the leading corrections to the ground-state energy within one-step replica symmetry breaking. The effects due to the breaking of replica symmetry appear to be small in accordance with the intuitive picture that a few strong bonds per spin reduce the degree of frustration in the system.
Structures, properties and applications of multifunctional lignin nanofibres
Creators: name: Li, Yingjie
Publisher: name: University of British Columbia
Year: 2015

description: This study explored the feasibility of creating multifunctional lignin materials in nanofibre form to establish a material platform for the development of value-added products. Specifically, softwood kraft lignin was electrospun, thermostabilized and carbonized into carbon nanofibres. Subsequently, functionalization of lignin based carbon nanofibres were conducted by (1) designing lignin-based composite carbon nanofibre; (2) preparing architecturally-designed lignin-based nanofibres and (3) preparing architecturally-designed lignin-based composite nanofibres. Examples of the advanced applications of the functionalized lignin based nanofibres were demonstrated such as electromagnetic interference shielding, energy storage and actuator. Flexible composite carbon nanofibres were embedded with functional fillers e.g. flexible electromagnetic lignin carbon nanofibres embedded with magnetic nanoparticles was developed. The amorphous structure of lignin and the addition of functional fillers impart the mechanical flexibility to lignin carbon nanofibre mats. By combining the magnetic permeability of magnetic nanoparticles and the electrical conductivity of lignin carbon nanofibre, flexible multifunctional lignin composite carbon nanofibres were created. Electromagnetic shielding effectiveness (SE) of lignin-based carbon nanofibres was comparable to that of the petroleum-based (such as polyacrylonitrile (PAN)-based) nanofibres. The feasibility of using above flexible composite carbon nanofibres from lignin as the lithium ion battery anode was demonstrated. This anode is free-standing, binder-free and mechanically flexible mats. Using lignin nanofibres electrodes and solid electrolytes, flexible solid-state lithium ion batteries were successfully assembled and characterized. Moreover, functions were added to electrospun lignin nanofibres by developing architecturally-designed lignin based thermostabilized nanofibres. A unique actuating phenomenon in thermostabilized lignin nanofibres was observed. It exhibits fast, reversible and dramatic mechanical deformation and recovery in response to environmental moisture gradient at milliseconds level. The actuation mechanism was investigated at the molecular level, and fibre assembly level. In summary, this study demonstrated that renewable biomaterials such as lignin has the potential for adding value through multifunctionalization in nanofibres form, thus creating a promising material platform for petroleum free feedstock for advanced applications.
CME on CME Interaction on January 17, 2005
Creators: name: Bouratzis, C.
name: Preka-Papadima, P.
name: Moussas, X.
name: Hillaris, A. E.
name: Caroubalos, C.
name: Alissandrakis, C. E.
name: Tsitsipis, P.
name: Kontogeorgos, A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: On January 17, 2005 a complex radio event associated with an X3.8 SXR flare and two fast Halo CMEs (CME1 & CME2 henceforward) in close succession was observed. We present combined ARTEMIS-IV & WIND WAVES dynamic spectra which provide a complete view of the radio emission induced by shock waves and electron beams from the low corona to about 1 A.U. These are supplemented with data, from the Nançay Radioheliograph (NRH), GOES, EIT and LASCO for the study of the associated flare and CME activity.
description: 2 pages 1 Figure
Hierarchy of integrable Hamiltonians describing of nonlinear n-wave interaction
Creators: name: Odzijewicz, Anatol
name: Goliński, Tomasz
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Physical sciences

description: In the paper we construct an hierarchy of integrable Hamiltonian systems which describe the variation of n-wave envelopes in nonlinear dielectric medium. The exact solutions for some special Hamiltonians are given in terms of elliptic functions of the first kind.
description: 17 pages
Numerical integration of stochastic contact Hamiltonian systems via stochastic Herglotz variational principle
Creators: name: Zhan, Qingyi
name: Duan, Jinqiao
name: Li, Xiaofan
name: Li, Yuhong
Publisher: name: arXiv
Year: 2022
Subjects: subject: Numerical Analysis (math.NA)
subject: FOS: Mathematics
subject: 37C50, 65C30

description: In this work we construct a stochastic contact variational integrator and its discrete version via stochastic Herglotz variational principle for stochastic contact Hamiltonian systems. A general structure-preserving stochastic contact method is devised, and the stochastic contact variational integrators are established. The implementation of this approach is validated by the numerical experiments.
description: 24 pages,15 figures
Trans-Tokyo Bay Highway Project - Challenges and learnings
Creators: name: Singh, Abhishek
Publisher: name: Zenodo
Year: 2019
Subjects: Under sea construction

description: The Trans-Tokyo Bay Highway was constructed;

a) in a relatively deep sea;

b) crossing heavy shipping routes;

c) under poor ground conditions; and

d) with a high seismic activity.

Several geotechnical engineering design and construction problems had to be solved for the success of the project.
Fermion Coherence Hamiltonians
Creators: name: Cherbal, O.
name: Drir, M.
name: Maamache, M.
name: Trifonov, D. A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We have established that the most general form of Hamiltonian that preserves fermionic coherent states stable in time, is that of the nonstationary free fermionic oscillator. This is to be compared with the earlier result of boson coherence Hamiltonian, which is of the more general form of the nonstationary forced bosonic oscillator. If however one admits Grassmann variables as Hamiltonian parameters then the coherence Hamiltonian takes again the form of (Grassmannian fermionic) forced oscillator.
description: latex, 10 pages, no figures
Ion-driven destabilization of a toroidal electron plasma -- A 3D3VPIC Simulation
Creators: name: Khamaru, Swapnali
name: Ganesh, Rajaraman
name: Sengupta, Meghraj
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Ion resonance instability of toroidal electron plasmas in a tight aspect ratio axisymmetric toroidal device is reported for ${Ar}^+$ ions of different initial density values using a high fidelity 3D3V PIC solver. Stability of a recently discovered quiescent quasi-steady state (QQS) of a toroidal electron plasma obtained from "seed" solution as a result of entropy extremization at zero inertia, is addressed to the presence of a small ion population. An ion fraction ($f$) and corresponding number of secondary electrons are preloaded into the system after the electron plasma attains a QQS state. Driven by the ions, the electron plasma exhibits destabilized "center of charge motion" ($m = 1$) along with increased poloidal mode coupling ($m = 1$ to $9$) with dominant $m = 2$ mode. The growth in wall probe current is algebraic in nature and increases for $f$ $\geq$ $0.005$, showing saturation at later time. Higher values of ion temperatures than the electron temperatures indicate a resonant energy transfer from electron plasma to ions via ion-resonance and concomitant ion heating. The volume averaged temperature value of the electron plasma rises with simulation time, attaining a quasi-steady nature near the end of the simulation time. As can be expected from conservation of adiabatic invariants, the flux tube averaged electron temperatures along parallel and perpendicular directions are found to scale as $1/R^2$ and $1/R$ respectively, where $R$ is the major radial variable, though the plasma is nearly collision-less.
description: 20 pages, 16 figures
Calibration of Equilibrium Tide Theory for Extrasolar Planet Systems
Creators: name: Hansen, Brad
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We provide an 'effective theory' of tidal dissipation in extrasolar planet systems by empirically calibrating a model for the equilibrium tide. The model is valid to high order in eccentricity and parameterised by two constants of bulk dissipation - one for dissipation in the planet and one for dissipation in the host star. We are able to consistently describe the distribution of extrasolar planetary systems in terms of period, eccentricity and mass (with a lower limit of a Saturn mass) with this simple model. Our model is consistent with the survival of short-period exoplanet systems, but not with the circularisation period of equal mass stellar binaries, suggesting that the latter systems experience a higher level of dissipation than exoplanet host stars. Our model is also not consistent with the explanation of inflated planetary radii as resulting from tidal dissipation. The paucity of short period planets around evolved A stars is explained as the result of enhanced tidal inspiral resulting from the increase in stellar radius with evolution.
description: 47 pages, 19 figures in ApJ ms style; to appear in ApJ
Ultra-low threshold continuous-wave quantum dot mini-BIC lasers
Creators: name: Zhong, Hancheng
name: Yang, Jiawei
name: Ding, Zhengqing
name: Rao, Mujie
name: Zhou, Lidan
name: Chen, Yingxin
name: Yu, Ying
name: Yu, Siyuan
Publisher: name: arXiv
Year: 2022
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Highly compact lasers with ultra-low threshold and single-mode continuous wave (CW) operation have been a long sought-after component for photonic integrated circuits (PICs). Photonic bound states in the continuum (BICs), due to their excellent ability of trapping light and enhancing light-matter interaction, have been investigated in lasing configurations combining various BIC cavities and optical gain materials. However, the realization of BIC laser with a highly compact size and an ultra-low CW threshold has remained elusive. We demonstrate room temperature CW BIC lasers in the 1310 nm O-band wavelength range, by fabricating a miniaturized BIC cavity in an InAs/GaAs epitaxial quantum dot (QD) gain membrane. By enabling effective trapping of both light and carriers in all three dimensions, ultra-low threshold of 12 μW (0.052 kW/cm^2) is achieved. Single-mode lasing is also realized in cavities as small as only 5*5 unit-cells (~2.5*2.5 μm^2 cavity size) with a mode volume of 1.16(λ/n)^3. With its advantages in terms of a small footprint, ultralow power consumption, robustness of fabrication and adaptability for integration, the mini-BIC lasers offer a perspective light source for future PICs aimed at high-capacity optical communications, sensing and quantum information.
SAT-NGP : Unleashing Neural Graphics Primitives for Fast Relightable Transient-Free 3D reconstruction from Satellite Imagery
Creators: name: Billouard, Camille
name: Derksen, Dawa
name: Sarrazin, Emmanuelle
name: Vallet, Bruno
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: Current stereo-vision pipelines produce high accuracy 3D reconstruction when using multiple pairs or triplets of satellite images. However, these pipelines are sensitive to the changes between images that can occur as a result of multi-date acquisitions. Such variations are mainly due to variable shadows, reflexions and transient objects (cars, vegetation). To take such changes into account, Neural Radiance Fields (NeRF) have recently been applied to multi-date satellite imagery. However, Neural methods are very compute-intensive, taking dozens of hours to learn, compared with minutes for standard stereo-vision pipelines. Following the ideas of Instant Neural Graphics Primitives we propose to use an efficient sampling strategy and multi-resolution hash encoding to accelerate the learning. Our model, Satellite Neural Graphics Primitives (SAT-NGP) decreases the learning time to 15 minutes while maintaining the quality of the 3D reconstruction.
description: 5 pages, 3 figures, 1 table; Accepted to International Geoscience and Remote Sensing Symposium (IGARSS) 2024; Code available at https://github.com/Ellimac0/SAT-NGP
Wide-angle and relativistic effects in Fourier-space clustering statistics
Creators: name: Noorikuhani, Milad
name: Scoccimarro, Roman
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Galaxy power spectrum and bispectrum signals are distorted by peculiar velocities and other relativistic effects arising from a perturbed spacetime background. In addition, study of correlation functions of tracers in Fourier space is often done in the plane-parallel approximation under which it is assumed that line-of-sight (LOS) vectors are parallel. In this work we show that a simple perturbative procedure can be employed for a fast evaluation of beyond plane-parallel (wide-angle) corrections to the power spectrum and bispectrum. We also show that evolution of linear matter density fluctuations in a relativistic context can be found from a simple method. For the power spectrum at linear level, we compare leading order wide-angle contributions to multipoles of the galaxy power spectrum with those from non-integrated and integrated relativistic corrections and estimate their possible contamination on local fNL measurements to be of order a few. We also compute wide-angle corrections in the presence of nonlinear terms at one-loop order. For the bispectrum, we show that wide-angle effects alone, even with fully symmetric choices of LOS, give rise to imaginary, odd-parity multipoles of the galaxy bispectrum (dipole, octupole, etc.) which are in many cases larger than previously known ones of relativistic origin. We calculate these contributions and provide an estimator for measuring the leading order bispectrum dipole from data, using a symmetric LOS definition. Finally, we calculate the leading order corrections to multipoles of real plane-parallel bispectrum multipoles and estimate the apparent local fNL induced to be of order unity.
description: Minor improvements and corrections, discussion added about inclusion of window function, matches the published version
A population of red candidate massive galaxies ~600 Myr after the Big Bang
Creators: name: Labbe, Ivo
name: van Dokkum, Pieter
name: Nelson, Erica
name: Bezanson, Rachel
name: Suess, Katherine
name: Leja, Joel
name: Brammer, Gabriel
name: Whitaker, Katherine
name: Mathews, Elijah
name: Stefanon, Mauro
name: Wang, Bingjie
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Galaxies with stellar masses as high as $\sim 10^{11}$ solar masses have been identified out to redshifts $z \sim 6$, approximately one billion years after the Big Bang. It has been difficult to find massive galaxies at even earlier times, as the Balmer break region, which is needed for accurate mass estimates, is redshifted to wavelengths beyond $2.5\mum$. Here we make use of the $1-5\mum$ coverage of the JWST early release observations to search for intrinsically red galaxies in the first ~750 million years of cosmic history. In the survey area, we find six candidate massive galaxies (stellar mass $>10^{10}$ solar masses) at $7.4 < z < 9.1$, 500 - 700 Myr after the Big Bang, including one galaxy with a possible stellar mass of $\sim 10^{11}$ solar masses. If verified with spectroscopy, the stellar mass density in massive galaxies would be much higher than anticipated from previous studies based on rest-frame ultraviolet-selected samples.
description: Accepted for publication in Nature. Updated to match the accepted version. Significant revision with updated calibration and stellar masses. Coordinates and fluxes of the sources can be found here: https://github.com/ivolabbe/red-massive-candidates
Astronomy, Space Science and Geopolitics
Creators: name: Courvoisier, Thierry J. -L.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Astronomy has played a major part in the development of civilisations, not only through conceptual developments, but most importantly through the very practical gains obtained through the observation of Sun, Moon planets and stars. Space sciences, including astronomy, have also played a major role in the development of modern societies, as engine for most subsequent space technology developments. Present trends tend to decrease the role of science in space development. This trend should be reversed to give modern "societies" their independence in space related matters that permeate the lives of all inhabitants of the Earth.
description: Contribution to the IAU symposium 260 "The role of Astronomy in Society and Culture"
H.E.S.S. Observations of strong flaring activity of Mrk421 in February 2010
Creators: name: Tluczykont, Martin
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The high-frequency peaked BL Lac object Mrk421 has shown a strong outburst of activity during February 2010. This high state, first detected by VERITAS on 16th of February, was followed up by H.E.S.S. during four subsequent nights at an average zenith angle of 62.4$^\circ$. In the first night of observations by H.E.S.S., the average flux level above 1 TeV was 4 times the level of the Crab Nebula flux, decreasing to a third of this value over the subsequent observation nights. The H.E.S.S. data shows an energy spectrum compatible with previous measurements, extending up to 20 TeV. The observed spectral shape can be well described by a powerlaw with a spectral index of $Γ= 2.05\,\pm\,0.22$, an exponential cutoff $E_{cut} = (3.4\,\pm\,0.6)$\,TeV and a flux normalization $ϕ_0 = (1.96\,\pm\,0.32)\,10^{-11}$\,cm$^{-2}$s$^{-1}$TeV$^{-1}$ at decorrelation energy $E_0 = 2.739$\,TeV. The observed integral flux varies on a night-by-night basis between 1.4 and 4.8 times the flux of the Crab Nebula.
description: Second version: corrected a wrongly placed figure captions. Figure 1 now has a more comprehensive caption and Figure 2 now has the correct caption (was caption of Figure 1 before) In Procceedings of Texas Symposium 2010, Heidelberg, Germany, Pos(Texas 2010)197
Euclidean Dynamical Triangulations Revisited
Creators: name: Asaduzzaman, Muhammad
name: Catterall, Simon
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: We conduct numerical simulations of a model of four dimensional quantum gravity in which the path integral over continuum Euclidean metrics is approximated by a sum over combinatorial triangulations. At fixed volume the model contains a discrete Einstein-Hilbert term with coupling $κ$ and local measure term with coupling $β$ that weights triangulations according to the number of simplices sharing each vertex. We map out the phase diagram in this two dimensional parameter space and compute a variety of observables that yield information on the nature of any continuum limit. Our results are consistent with a line of first order phase transitions with a latent heat that decreases as $κ\to\infty$. We find a Hausdorff dimension along the critical line that approaches $D_H=4$ for large $κ$ and a spectral dimension that is consistent with $D_s=\frac{3}{2}$ at short distances. These results are broadly in agreement with earlier works on Euclidean dynamical triangulation models which utilize degenerate triangulations and/or different measure terms and indicate that such models exhibit a degree of universality.
Metric Radio Bursts and Fine Structures Observed on January 20, 2005
Creators: name: Bouratzis, C.
name: Preka-Papadima, P.
name: Moussas, X.
name: Hillaris, A. E.
name: Kurt, V.
name: Tsitsipis, P.
name: Kontogeorgos, A.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: A major radio event, associated with an X7.1/2B flare in AR720 and a fast CME was observed on January 20, 2005 with the radio-spectrograph ARTEMIS-IV; it was particularly intense and with a complex radio signature with rich fine structure which was recorded in the 270-420 MHz range at high resolution (100 samples/sec). The fine structure is compared with similar results in the decimetric and microwave frequency range. It was found to approximately match the comprehensive Ondrejov Classification in the spectral range 0.8-2 GHz.
description: 2 Pages, 1 Figure Proceedings of the 9th International Conference of the Hellenic Astronomical Society, proceedings of a conference held 20-24 September 2009 in Athens, Greece. Edited by Kanaris Tsinganos, Despina Hatzidimitriou, and Titos Matsakos. San Francisco: Astronomical Society of the Pacific, 2010., p.41
The morphological growth responses of African Yam Bean (Sphenostylis stenocarpa) in a cadmium polluted soil
Creators: name: E.O., Ohanmu
name: Ikhajiagbe, Beckley
name: Anoliefo, Geoffrey
Publisher: name: figshare
Year: 2022
Subjects: Botany
Biotechnology

description: This study investigated the morphological growth responses of African yam bean (AYB) (sphenostylis stenocarpa) in a cadmium polluted soil. Soil was polluted with cadmium (as CdCl2) on the basis of the statutory ecological screening values (ESV); 0, 2.5 and 5 times the ESV. The morphology of polluted by cadmium was assessed using five AYB accessions namely; TSs-91, -92, -93, -94, and -95 respectively. The parameters studied were the shoot height, number of leaves, leaflet area folded, curled and forage leaves by insects. Results showed that Cadmium pollution resulted to significant reduction in all plant parameters studied during the 20 weeks period of observation. The shoot height of TSs-92 had a reduced difference of 8.9 cm compared to the control. There was no significant difference in leaflet area between the TSs-94 and the control. The highest number of leaf curling and folding were more observed in the Cd-5ESV treatments. In conclusion, TSs-92 has the potential to perform in Cd stressed soil and further research be carried out to check it response at molecular level.
Local space time constant mean curvature and constant expansion foliations
Creators: name: Metzger, Jan
name: Diaz, Alejandro Peñuela
Publisher: name: arXiv
Year: 2022
Subjects: subject: Differential Geometry (math.DG)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: Inspired by the small sphere-limit for quasi-local energy we study local foliations of surfaces with prescribed mean curvature. Following the strategy used by Ye in 1991 to study local constant mean curvature foliations, we use a Lyapunov Schmidt reduction in an n+1 dimensional manifold equipped with a symmetric 2-tensor to construct the foliations around a point, prove their uniqueness and show their nonexistence conditions. To be specific, we study two foliation conditions. First we consider constant space-time mean curvature surfaces. These foliations were used by Cederbaum and Sakovich to characterize the center of mass in general relativity. Second, we study local foliations of constant expansion surfaces.
Detection of gravitational waves by pulsar timing
Creators: name: Rodin, Alexander E.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: A new approach to the problem of gravitational waves detection based on simultaneous timing of several pulsars and subsequent expansion of the post-fit timing data into components of different spectral kind (with different spectral indices) is proposed. Presence of a signal caused by stochastic gravitational waves in spectral components is tested with the two-point angular correlation function as proposed in the pulsar timing array. This new approach was applied to timing data of a few millisecond pulsars and allowed to detect a signature similar to one predicted for gravitational wave background at relatively high confidence level: correlation coefficient between experimental and theoretical two-point correlations $ρ=0.82\pm 0.07$.
description: 4 pages, 3 figures
Advantageous punishers in nature
Creators: name: Liu, Xinsheng
name: Guo, Wanlin
Publisher: name: arXiv
Year: 2010
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: FOS: Biological sciences

description: The evolution and maintenance of cooperation fascinated researchers for several decades. Recently, theoretical models and experimental evidence show that costly punishment may facilitate cooperation in human societies, but may not be used by winners. The puzzle how the costly punishment behaviour evolves can be solved under voluntary participation. Could the punishers emerge if participation is compulsory? Is the punishment inevitably a selfish behaviour or an altruistic behaviour? The motivations behind punishment are still an enigma. Based on public goods interactions, we present a model in which just a certain portion of the public good is divided equally among all members. The other portion is distributed to contributors when paying a second cost. Contributors who are willing to pay a second cost can be costly (and then altruistic) punishers, but they can also flourish or dominate the population, in this case we may call them "advantageous punishers". We argue that most of successful cooperators and punishers in nature are advantageous punishers, and costly punishment mostly happens in humans. This indicates a universal surviving rule: contributing more and gaining more. Our models show theoretically that the original motivation behind punishment is to retrieve deserved payoff from their own contributions, a selfish incentive.
description: 13 pages, 3 figures
Efficient and precise quantum simulation of ultra-relativistic quark-nucleus scattering
Creators: name: Wu, Sihao
name: Du, Weijie
name: Zhao, Xingbo
name: Vary, James P.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: High Energy Physics - Theory (hep-th)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present an efficient and precise framework to quantum simulate the dynamics of the ultra-relativistic quark-nucleus scattering. This framework employs the eigenbasis of the asymptotic scattering system and implements a compact scheme for encoding this basis upon lattice discretization. It exploits the operator structure of the light-front Hamiltonian of the scattering system, which enables the Hamiltonian input that utilizes the quantum Fourier transform for efficiency. Our framework simulates the scattering by the efficient and precise algorithm of the truncated Taylor series. The qubit cost of our framework scales logarithmically with the Hilbert space dimension of the scattering system. The gate cost has optimal scaling with the simulation error and near optimal scaling with the simulation time. These scalings make our framework advantageous for large-scale dynamics simulations on future fault-tolerant quantum computers. We demonstrate our framework with a simple scattering problem and benchmark the results with those from the Trotter algorithm and the classical calculations, where good agreement between the results is found. Our framework can be generalized to simulate the dynamics of various scattering problems in quantum chromodynamics.
description: 28 pages, 11 figures. Comments are welcome!
The role of long distance contribution to the $B\to K^{(\ast)} \ell^+ \ell^-$ in the Standard Model
Creators: name: Ladisa, Massimo
name: Santorelli, Pietro
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We investigate rare semileptonic $B \to K^\ast\ell^+\ell^-$ by looking at the long distance contributions. Our analysis is limited to the very small values of physical accessible range of invariant mass of the leptonic couple $q^2$. We show that the light quarks loop has to be accounted for, along with the charming penguin contribution, in order to accurately compute the $q^2$-spectrum in the Standard Model. Such a long distance contribution may also play a role in the analysis of the lepton flavour universality violation in this process.
description: 12 pages, 7 figures, 1 table
Nuclear effects in atomic transitions
Creators: name: Pálffy, Adriana
Publisher: name: arXiv
Year: 2011
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Atomic electrons are sensitive to the properties of the nucleus they are bound to, such as nuclear mass, charge distribution, spin, magnetization distribution, or even excited level scheme. These nuclear parameters are reflected in the atomic transition energies. A very precise determination of atomic spectra may thus reveal information about the nucleus, otherwise hardly accessible via nuclear physics experiments. This work reviews theoretical and experimental aspects of the nuclear effects that can be identified in atomic structure data. An introduction to the theory of isotope shifts and hyperfine splitting of atomic spectra is given, together with an overview of the typical experimental techniques used in high-precision atomic spectroscopy. More exotic effects at the borderline between atomic and nuclear physics, such as parity violation in atomic transitions due to the weak interaction, or nuclear polarization and nuclear excitation by electron capture, are also addressed.
description: review article, 53 pages, 14 figures
Improving the factor structure of psychological scales : the Expanded format as the alternative to the Likert scale format
Creators: name: Zhang, Xijuan
Publisher: name: University of British Columbia
Year: 2015

description: Many psychological scales written in the Likert format include reverse worded (RW) items in order to control acquiescence bias. However, studies have shown that RW items often contaminate the factor structure of the scale by creating one or more method factors. The present study examines an alternative scale format, called the Expanded format, which replaces each response option in the Likert scale with a full sentence. We hypothesized that this format would result in a cleaner factor structure as compared to the Likert format. We tested this hypothesis on three popular psychological scales: the Rosenberg Self-Esteem scale, the Conscientiousness subscale of the Big Five Inventory, and the Beck Depression Inventory II. Scales in both formats showed comparable reliabilities and convergent validities. However, scales in the Expanded format had better (i.e., lower and more theoretically defensible) dimensionalities than scales in the Likert format, as assessed by both exploratory factor analyses and confirmatory factor analyses. We encourage further study and wider use of the Expanded format, particularly when the dimensionality of a scale is of theoretical interest.
Updated constraints on amplitude and tilt of the tensor primordial spectrum
Creators: name: Galloni, Giacomo
name: Bartolo, Nicola
name: Matarrese, Sabino
name: Migliaccio, Marina
name: Ricciardone, Angelo
name: Vittorio, Nicola
Publisher: name: arXiv
Year: 2022
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We have taken a comprehensive approach to update the limits on the tensor-to-scalar ratio ($r$) and the tensor spectral index ($n_t$), using 10 datasets from the BICEP/Keck Array 2015 and 2018, Planck releases 3 and 4, and LIGO-Virgo-KAGRA Collaboration. By fitting the complete $Λ$CDM+$r$+$n_t$ model with two different approaches for the tensor sector, we have not only established which method is the most reliable, but have also achieved the strongest constraint on the tensor-to-scalar ratio in current literature: $r<0.028$ and $-1.37 < n_t < 0.42$ at 95% confidence level. Furthermore, our examination of the common signal detected by the NANOGrav Collaboration further confirms that a simple power-law cannot reconcile the constraints from different datasets if the NANOGrav detection is due to a primordial inflationary gravitational wave background, as previously shown in the literature.
description: Version coherent with published one. Added new analysis in section 2.4. Added new section 5.1. Added appendix B. Conclusions unchanged
Streaming Algorithms for Diversity Maximization with Fairness Constraints
Creators: name: Wang, Yanhao
name: Fabbri, Francesco
name: Mathioudakis, Michael
Publisher: name: arXiv
Year: 2022
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Diversity maximization is a fundamental problem with wide applications in data summarization, web search, and recommender systems. Given a set $X$ of $n$ elements, it asks to select a subset $S$ of $k \ll n$ elements with maximum \emph{diversity}, as quantified by the dissimilarities among the elements in $S$. In this paper, we focus on the diversity maximization problem with fairness constraints in the streaming setting. Specifically, we consider the max-min diversity objective, which selects a subset $S$ that maximizes the minimum distance (dissimilarity) between any pair of distinct elements within it. Assuming that the set $X$ is partitioned into $m$ disjoint groups by some sensitive attribute, e.g., sex or race, ensuring \emph{fairness} requires that the selected subset $S$ contains $k_i$ elements from each group $i \in [1,m]$. A streaming algorithm should process $X$ sequentially in one pass and return a subset with maximum \emph{diversity} while guaranteeing the fairness constraint. Although diversity maximization has been extensively studied, the only known algorithms that can work with the max-min diversity objective and fairness constraints are very inefficient for data streams. Since diversity maximization is NP-hard in general, we propose two approximation algorithms for fair diversity maximization in data streams, the first of which is $\frac{1-\varepsilon}{4}$-approximate and specific for $m=2$, where $\varepsilon \in (0,1)$, and the second of which achieves a $\frac{1-\varepsilon}{3m+2}$-approximation for an arbitrary $m$. Experimental results on real-world and synthetic datasets show that both algorithms provide solutions of comparable quality to the state-of-the-art algorithms while running several orders of magnitude faster in the streaming setting.
description: 13 pages, 11 figures; published in ICDE 2022
Significance of the nature of disorder on the universal features of the spatio-temporal correlations of two-dimensional Coulomb-clusters
Creators: name: Jami, Prashanti
name: Ash, Biswarup
name: Ghosal, Amit
Publisher: name: arXiv
Year: 2022
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We comprehend the role of imperfections in materials consisting of interacting particles, arising from different origins on their universal features. Specifically, we report the static and dynamic responses in a cluster of Coulomb interacting particles in two dimensions. Confined systems with pinned impurities are studied, and results are compared with those from irregularly trapped system of particles. While the disorder of first type leads to diffusive single-particle dynamics, the motion of a single particle in an irregular trap is chaotic but ballistic. The many-particle system does not differentiate between these two models of disorder insofar as their qualitative properties are concerned -- particularly for describing the thermal melting of the underlying Coulomb-"solid". However, quantitative differences persist -- the relaxation time scales differ significantly by tuning impurity concentration.
description: 10 pages, 11 figures
Preparation and characterization of cellulosic conductive paper
Creators: name: Fang, Lulu
name: Liu, Lu
name: Zhao, Xin
name: Kong, Fangong
name: Chen, Honglei
name: Wang, Shoujuan
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biophysics
subject: Biochemistry
subject: Space Science
subject: Physical Sciences not elsewhere classified
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Genetics
subject: Pharmacology
subject: Biotechnology
subject: Environmental Sciences not elsewhere classified
subject: Chemical Sciences not elsewhere classified
subject: Science Policy
subject: Infectious Diseases
subject: FOS: Health sciences

description: Silver nanowires were successfully prepared by polyol method using silver nitrate as silver source, ethylene glycol as solvent and reducing agent, and ferric chloride as nucleating agent and polyvinylpyrrolidone (PVP) as structure directing agent and protective agent. The obtained silver nanowires were mixed with Kraft pulp fibers and bacterial cellulose to prepare conductive paper via simple filtration process. The results indicated that the size of silver nanowires can be regulated by the dosage of ferric chloride used. At optimal dosage of FeCl3, the prepared silver nanowires can reach 20 μm length, 100 nm width, and 200 of width/diameter ratio. The adding of bacterial cellulose in preparing the conductive paper greatly enhanced the retention ratio of silver nanowires as well as the stress and strain of the conductive paper. The stress and strain of the paper with bacterial cellulose were increased by 60% and 7%, respectively, compared with that of the paper without bacterial cellulose. The maximum retention ratio and the highest recovery ratio of silver nanowires in conductive paper reached 94% and 75%, respectively. The resistance of as-prepared conductive paper was only 0.9 Ω. In conductive paper, the silver nanowires attached to the paper-based materials with cellulose fibers as the substrate, which achieved the electrical conductivity of paper-based materials. This conductive paper can be applied as antistatic, antibacterial packaging and conductive material.
Bose-Hubbard dynamics of polaritons in a chain of circuit QED cavities
Creators: name: Leib, Martin
name: Hartmann, Michael J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We investigate a chain of superconducting stripline resonators, each interacting with a transmon qubit, that are capacitively coupled in a row. We show that the dynamics of this system can be described by a Bose-Hubbard Hamiltonian with attractive interactions for polaritons, superpositions of photons and qubit excitations. This setup we envisage constitutes one of the first platforms where all technological components that are needed to experimentally study chains of strongly interacting polaritons have already been realized. By driving the first stripline resonator with a microwave source and detecting the output field of the last stripline resonator one can spectroscopically probe properties of the system in the driven dissipative regime. We calculate the stationary polariton density and density-density correlations $g^{(2)}$ for the last cavity which can be measured via the output field. Our results display a transition from a coherent to a quantum field as the ratio of on site interactions to driving strength is increased.
Fractality in tumor growth at the avascular stage from a generalization of the logistic-Gompertz dynamics
Creators: name: Miranda, Luiza M. S.
name: Souza, Andre M. C.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Medical Physics (physics.med-ph)
subject: FOS: Physical sciences

description: The dynamics between healthy and malignant cells at the avascular stage of growth is described by a set of chemical reactions representing the populations of both types of cells. We obtain a generalization of the logistic-Gompertz dynamics and study the consequences in terms of the properties of tumor growth associated with the Warburg effect, mitosis and nutrient and space apoptosis. As a result of the stochastic nature of this process, a fractal morphology is observed in this region. Our results agree with experimental results for growth of tumor cell colonies.
description: 12 pages, 5 figures
The Glueball in a Chiral Linear Sigma Model with Vector Mesons
Creators: name: Janowski, Stanislaus
name: Parganlija, Denis
name: Giacosa, Francesco
name: Rischke, Dirk H.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a two-flavour linear sigma model with global chiral symmetry and (axial-)vector mesons as well as an additional glueball degree of freedom. We study the structure of the well-established scalar resonances f0(1370) and f0(1500): by a fit to experimentally known decay widths we find that f0(1370) is predominantly a \bar{q}q state and f0(1500) is predominantly a glueball state. The overall phenomenology of these two resonances can be well described. Other assignments for our mixed quarkonium-glueball states are also tested, but turn out to be in worse agreement with the phenomenology. As a by-product of our analysis, the gluon condensate is determined.
description: 8 pages
Assessing public transportation option as a potential solution to the transportation challenges in the State of Kuwait
Creators: name: Jamal, Esraa' Ali
Publisher: name: University of British Columbia
Year: 2015

description: Transportation congestion is an increasingly important issue in modern urban planning. A sustainable transportation system should assure people’s safety, environmental protection, economic support, social justice, and accessibility for both people and goods. Kuwait is no exception to this challenge because rapid growth has increased the pressure on its existing transportation system. The objectives of this study are to understand the people’s awareness of transportation problems and the impact associated with them in Kuwait, to examine people’s perceptions of daily traffic congestion and how it affects them emotionally and physically in Kuwait, and to study the attitude of Kuwaiti citizens and residents towards using the public bus service. An online survey was used to examine these factors and a sample of five hundred users was obtained. Balance adjusting technique was applied to correct and match the sample proportions with the population proportions. The study questions have been investigated by using the chi-square test for independence. The primary findings showed significant associations between use of the public bus and the users’ nationality, gender, age, education and income level. In relation to the existing public bus service, men are 2.6 times more likely to use it than are women, and non-Kuwaiti residents are 6.4 times more likely to use it than are Kuwaitis. In addition, the perception of daily traffic congestion varied among different nationalities. Kuwaitis perceptions of the daily commuting trips indicate that it consumes a large sum of time. Non-Kuwaitis use of public transit is affected by the number of years they have been living in Kuwait. The results of this study fill a gap in the knowledge of socioeconomic and cultural factors that may influence the success of potential sustainable solutions to the transportation challenges in the State of Kuwait.