cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Orbit Uncertainty Propagation and Sensitivity Analysis With Separated Representations
Creators: name: Balducci, Marc
name: Jones, Brandon
name: Doostan, Alireza
Publisher: name: arXiv
Year: 2016
Subjects: subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: Most approximations for stochastic differential equations with high-dimensional, non-Gaussian inputs suffer from a rapid (e.g., exponential) increase of computational cost, an issue known as the curse of dimensionality. In astrodynamics, this results in reduced accuracy when propagating an orbit-state probability density function. This paper considers the application of separated representations for orbit uncertainty propagation, where future states are expanded into a sum of products of univariate functions of initial states and other uncertain parameters. An accurate generation of separated representation requires a number of state samples that is linear in the dimension of input uncertainties. The computation cost of a separated representation scales linearly with respect to the sample count, thereby improving tractability when compared to methods that suffer from the curse of dimensionality. In addition to detailed discussions on their construction and use in sensitivity analysis, this paper presents results for three test cases of an Earth orbiting satellite. The first two cases demonstrate that approximation via separated representations produces a tractable solution for propagating the Cartesian orbit-state uncertainty with up to 20 uncertain inputs. The third case, which instead uses Equinoctial elements, reexamines a scenario presented in the literature and employs the proposed method for sensitivity analysis to more thoroughly characterize the relative effects of uncertain inputs on the propagated state.
A Geometric Approach to Dynamical Model-Order Reduction
Creators: name: Feppon, Florian
name: Lermusiaux, Pierre F. J.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Dynamical Systems (math.DS)
subject: FOS: Mathematics
subject: 65C20, 53B21, 65F30, 15A23, 53A07, 35R60, 65M15

description: Any model order reduced dynamical system that evolves a modal decomposition to approximate the discretized solution of a stochastic PDE can be related to a vector field tangent to the manifold of fixed rank matrices. The Dynamically Orthogonal (DO) approximation is the canonical reduced order model for which the corresponding vector field is the orthogonal projection of the original system dynamics onto the tangent spaces of this manifold. The embedded geometry of the fixed rank matrix manifold is thoroughly analyzed. The curvature of the manifold is characterized and related to the smallest singular value through the study of the Weingarten map. Differentiability results for the orthogonal projection onto embedded manifolds are reviewed and used to derive an explicit dynamical system for tracking the truncated Singular Value Decomposition (SVD) of a time-dependent matrix. It is demonstrated that the error made by the DO approximation remains controlled under the minimal condition that the original solution stays close to the low rank manifold, which translates into an explicit dependence of this error on the gap between singular values. The DO approximation is also justified as the dynamical system that applies instantaneously the SVD truncation to optimally constrain the rank of the reduced solution. Riemannian matrix optimization is investigated in this extrinsic framework to provide algorithms that adaptively update the best low rank approximation of a smoothly varying matrix. The related gradient flow provides a dynamical system that converges to the truncated SVD of an input matrix for almost every initial data.
Solvable Model of a Generic Trapped Mixture of Interacting Bosons: Reduced Density Matrices and Proof of Bose-Einstein Condensation
Creators: name: Alon, Ofir E.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A mixture of two kinds of identical bosons, species $1$ and species $2$, held in a harmonic potential and interacting by harmonic intra-species and inter-species particle-particle interactions is discussed. To prove Bose-Einstein condensation of the mixture three steps are needed. First, we integrate the all-particle density matrix, employing a four-parameter matrix recurrence relations, down to the lowest-order intra-species and inter-species reduced density matrices of the mixture. Second, the coupled Gross-Pitaevskii (mean-field) equations of the mixture are solved analytically. Third, we analyze the mixture's reduced density matrices in the limit of an infinite number of particles of both species $1$ and $2$ (when the interaction parameters, i.e., the products of the number of particles times the intra-species and inter-species interaction strengths, are held fixed) and prove that: (i) Both species $1$ and $2$ are 100\% condensed; (ii) The inter-species reduced density matrix per particle is separable and given by the product of the intra-species reduced density matrices per particle; and (iii) The mixture's energy per particle, and reduced density matrices and densities per particle all coincide with the Gross-Pitaevskii quantities. Finally, when the infinite-particle limit is taken with respect to, say, species $1$ only (with interaction parameters held fixed) we prove that: (iv) Only species $1$ is 100\% condensed and its reduced density matrix and density per particle, as well as the mixture's energy per particle, coincide with the Gross-Pitaevskii quantities of species $1$ alone; and (v) The inter-species reduced density matrix per particle is nonetheless separable and given by the product of the intra-species reduced density matrices per particle.
description: 31 pages
On the boundedness of periodic pseudo-differential operators
Creators: name: Cardona, Duván
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: Primary 58J40, Secondary 35S05, 42B05

description: In this paper we investigate the $L^p$-boundedness of certain classes of periodic pseudo-differential operators. The operators considered arise from the study of symbols on $\mathbb{T}^n\times\mathbb{Z}^n$ with limited regularity.
description: Pseudo-differential operators
Modified scattering for the critical nonlinear Schrödinger equation
Creators: name: Cazenave, Thierry
name: Naumkin, Ivan
Publisher: name: arXiv
Year: 2017
Subjects: subject: Analysis of PDEs (math.AP)
subject: FOS: Mathematics
subject: 35Q55

description: We consider the nonlinear Schrödinger equation $iu_t + Δu= λ|u|^{\frac {2} {N}} u $ in all dimensions $N\ge 1$, where $λ\in {\mathbb C}$ and $\Im λ\le 0$. We construct a class of initial values for which the corresponding solution is global and decays as $t\to \infty $, like $t^{- \frac {N} {2}}$ if $\Im λ=0$ and like $(t \log t)^{- \frac {N} {2}}$ if $\Im λ<0$. Moreover, we give an asymptotic expansion of those solutions as $t\to \infty $. We construct solutions that do not vanish, so as to avoid any issue related to the lack of regularity of the nonlinearity at $u=0$. To study the asymptotic behavior, we apply the pseudo-conformal transformation and estimate the solutions by allowing a certain growth of the Sobolev norms which depends on the order of regularity through a cascade of exponents.
Hydrogen bonding characterization in water and small molecules
Creators: name: Silvestrelli, Pier Luigi
Publisher: name: arXiv
Year: 2017
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: The prototypical Hydrogen bond in water dimer and Hydrogen bonds in the protonated water dimer, in other small molecules, in water cyclic clusters, and in ice, covering a wide range of bond strengths, are theoretically investigated by first-principles calculations based on the Density Functional Theory, considering a standard Generalized Gradient Approximation functional but also, for the water dimer, hybrid and van-der-Waals corrected functionals. We compute structural, energetic, and electrostatic (induced molecular dipole moments) properties. In particular, Hydrogen bonds are characterized in terms of differential electron densities distributions and profiles, and of the shifts of the centres of Maximally localized Wannier Functions. The information from the latter quantities can be conveyed into a single geometric bonding parameter that appears to be correlated to the Mayer bond order parameter and can be taken as an estimate of the covalent contribution to the Hydrogen bond. By considering the cyclic water hexamer and the hexagonal phase of ice we also elucidate the importance of cooperative/anticooperative effects in Hydrogen-bonding formation.
description: 11 figures
Edge-controlled half-metallic ferromagnetism and direct gap in ZrS2 nanoribbons
Creators: name: Lv, H. Y.
name: Lu, W. J.
name: Li, J. Y.
name: Xiao, R. C.
name: Wei, M. J.
name: Tong, P.
name: Zhu, X. B.
name: Sun, Y. P.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The electronic and magnetic properties of ZrS2 nanoribbons (NRs) are investigated based on the first-principles calculations. It is found that the ZrS2 NRs with armchair edges are all indirect-band-gap semiconductors without magnetism and the band-gap exhibits odd-even oscillation behavior with the increase of the ribbon width. For the NRs with zigzag edges, those with both edges S-terminated are nonmagnetic direct-band-gap semiconductors and the gap decreases monotonically as a function of the ribbon width. However, the NRs with one edge S-terminated and the other edge Zr-terminated are ferromagnetic half-metal, while those with both edges Zr-terminated tend to be ferromagnetic half-metal when the width $N\geq9$. The magnetism of both systems mainly originates from the unsaturated edge Zr atoms. Depending on the different edge configurations and ribbon widths, the ZrS2 NRs exhibit versatile electronic and magnetic properties, making them promising candidates for the applications of electronics and spintronics.
Clustering of quasars in a wide luminosity range at redshift 4 with Subaru Hyper Suprime-Cam wide field imaging
Creators: name: He, Wanqiu
name: Akiyama, Masayuki
name: Bosch, James
name: Enoki, Motohiro
name: Harikane, Yuichi
name: Ikeda, Hiroyuki
name: Kashikawa, Nobunari
name: Kawaguchi, Toshihiro
name: Komiyama, Yutaka
name: Lee, Chien-Hsiu
name: Matsuoka, Yoshiki
name: Miyazaki, Satoshi
name: Nagao, Tohru
name: Nagashima, Masahiro
name: Niida, Mana
name: Nishizawa, Atsushi J
name: Oguri, Masamune
name: Onoue, Masafusa
name: Oogi, Taira
name: Ouchi, Masami
name: Schulze, Andreas
name: Shirasaki, Yuji
name: Silverman, John D.
name: Tanaka, Manobu M.
name: Tanaka, Masayuki
name: Toba, Yoshiki
name: Uchiyama, Hisakazu
name: Yamashita, Takuji
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We examine the clustering of quasars over a wide luminosity range, by utilizing 901 quasars at $\overline{z}_{\rm phot}\sim3.8$ with $-24.73
description: 20 pages, 10 figures, submitted to PASJ
Dynamical histories of the IC348 and NGC1333 star-forming regions in Perseus
Creators: name: Parker, Richard J.
name: de Oliveira, Catarina Alves
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present analyses of the spatial distributions of stars in the young (1 - 3 Myr) star-forming regions IC348 and NGC1333 in the Perseus Giant Molecular Cloud. We quantify the spatial structure using the $\mathcal{Q}$-parameter and find that both IC348 and NGC1333 are smooth and centrally concentrated with $\mathcal{Q}$-parameters of 0.98 and 0.89 respectively. Neither region exhibits mass segregation ($Λ_{\rm MSR} = 1.1^{+0.2}_{-0.3}$ for IC348 and $Λ_{\rm MSR} = 1.2^{+0.4}_{-0.3}$ for NGC1333, where $Λ_{\rm MSR} \sim 1$ corresponds to no mass segregation), nor do the most massive stars reside in areas of enhanced stellar surface density compared to the average surface density, according to the $Σ_{\rm LDR}$ method. We then constrain the dynamical histories and hence initial conditions of both regions by comparing the observed values to $N$-body simulations at appropriate ages. Stars in both regions likely formed with sub-virial velocities which contributed to merging of substructure and the formation of smooth clusters. The initial stellar densities were no higher than $ρ\sim 100 - 500$M$_\odot$pc$^{-3}$ for IC348 and $ρ\sim 500 - 2000$M$_\odot$pc$^{-3}$ for NGC1333. These initial densities, in particular that of NGC1333, are high enough to facilitate dynamical interactions which would likely affect $\sim$10 per cent of protoplanetary discs and binary stars.
description: 13 pages, 9 figures, accepted for publication in MNRAS (23.03.2017)
Electric Field Tuning of Band Offsets in Transition Metal Dichalcogenides
Creators: name: Huang, Dennis
name: Kaxiras, Efthimios
Publisher: name: arXiv
Year: 2016
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We use first-principles calculations to investigate the band structure evolution of W$X_2$/Mo$X_2$ ($X$ = S, Se) heterobilayers under a perpendicular electric field. We characterize the extent to which the type-II band alignment in these compounds can be tuned or inverted electrostatically. Our results demonstrate two effects of stacking configuration. First, different stackings produce different net dipole moments, resulting in band offset variations that are larger than 0.1 eV. Second, based on symmetry constraints that depend on stacking, a perpendicular electric field may hybridize W$X_2$ and Mo$X_2$ bands that cross at the Brillouin Zone corner $K$. Our results suggest that external electric fields can be used to tune the physics of intralayer and interlayer excitons in heterobilayers of transition metal dichalcogenides.
description: 8 pages, 7 figures, main text and supplemental material
The fate of the gaseous disks of galaxies that fall into clusters
Creators: name: Ruggiero, Rafael
name: Neto, Gastão B. Lima
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Galaxy clusters are known to induce gas loss in infalling galaxies due to the ram pressure exerted by the intracluster medium over their gas content. In this paper, we investigate this process through a set of simulations of Milky Way like galaxies falling inside idealised clusters of 10$^{14}$ M$_\odot$ and 10$^{15}$ M$_\odot$, containing a cool-core or not, using the adaptive mesh refinement code RAMSES. We use these simulations to constrain how much of the initial mass contained in the gaseous disk of the galaxy will be converted into stars and how much of it will be lost, after a single crossing of the entire cluster. We find that, if the galaxy reaches the central region of a cool-core cluster, it is expected to lose all its gas, independently of its entry conditions and of the cluster's mass. On the other hand, it is expected to never lose all its gas after crossing a cluster without a cool-core just once. Before reaching the centre of the cluster, the SFR of the galaxy is always enhanced, by a factor of 1.5 to 3. If the galaxy crosses the cluster without being completely stripped, its final amount of gas is on average two times smaller after crossing the 10$^{15}$ M$_\odot$ cluster, relative to the 10$^{14}$ M$_\odot$ cluster. This is reflected in the final SFR of the galaxy, which is also two times smaller in the former, ranging from 0.5 $-$ 1 M$_\odot$ yr$^{-1}$, compared to 1 $-$ 2 M$_\odot$ yr$^{-1}$ for the latter.
description: Accepted for publication in MNRAS. 9 pages, 6 figures
Non-linear stability of a brane wormhole
Creators: name: Akai, Yumi
name: Nakao, Ken-ichi
Publisher: name: arXiv
Year: 2017
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We analytically study the non-linear stability of a spherically symmetric wormhole supported by an infinitesimally thin brane of negative tension, which has been devised by Barcelo and Visser. We consider a situation in which a thin spherical shell composed of dust falls into an initially static wormhole; The dust shell plays a role of the non-linear disturbance. The self-gravity of the falling dust shell is completely taken into account through Israel's formalism of the metric junction. When the dust shell goes through the wormhole, it necessarily collides with the brane supporting the wormhole. We assume the interaction between these shells is only gravity and show the condition under which the wormhole stably persists after the dust shell goes through it.
description: 32 pages, 10 figure. arXiv admin note: substantial text overlap with arXiv:1306.6917
Experimental realization of a long-range antiferromagnet in the Hubbard model with ultracold atoms
Creators: name: Mazurenko, Anton
name: Chiu, Christie S.
name: Ji, Geoffrey
name: Parsons, Maxwell F.
name: Kanász-Nagy, Márton
name: Schmidt, Richard
name: Grusdt, Fabian
name: Demler, Eugene
name: Greif, Daniel
name: Greiner, Markus
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Many exotic phenomena in strongly correlated electron systems emerge from the interplay between spin and motional degrees of freedom. For example, doping an antiferromagnet gives rise to interesting phases including pseudogap states and high-temperature superconductors. A promising route towards achieving a complete understanding of these materials begins with analytic and computational analysis of simplified models. Quantum simulation has recently emerged as a complementary approach towards understanding these models. Ultracold fermions in optical lattices offer the potential to answer open questions on the low-temperature regime of the doped Hubbard model, which is thought to capture essential aspects of the cuprate superconductor phase diagram but is numerically intractable in that parameter regime. A new perspective is afforded by quantum gas microscopy of fermions, which allows readout of magnetic correlations at the site-resolved level. Here we report the realization of an antiferromagnet in a repulsively interacting Fermi gas on a 2D square lattice of approximately 80 sites. Using site-resolved imaging, we detect (finite-size) antiferromagnetic long-range order (LRO) through the development of a peak in the spin structure factor and the divergence of the correlation length that reaches the size of the system. At our lowest temperature of T/t = 0.25(2) we find strong order across the entire sample. Our experimental platform enables doping away from half filling, where pseudogap states and stripe ordering are expected, but theoretical methods become numerically intractable. In this regime we find that the antiferromagnetic LRO persists to hole dopings of about 15%, providing a guideline for computational methods. Our results demonstrate that quantum gas microscopy of ultracold fermions in optical lattices can now address open questions on the low-temperature Hubbard model.
description: 15 pages, 9 figures
title: Investigating antimicrobial resistance by competition of Staphylococcus species
Creators: name: Amhimmid, Mohammed
Publisher: name: University of Liverpool Repository
Year: 2023

description: Staphylococcus aureus can invade the human skin microflora and cause many serious infections as an opportunistic pathogen. The anterior nares are its major niche where it colonises with diverse bacteria that interact and compete for the same resources and binding sites. The study of microbial competition and invasion increases our understanding of species dynamics and how they contribute to evolution of antibiotic resistance and impacts on human health. However, the genetic drivers in the evolution of competition and resistance remains unclear in the S. aureus niche. A deferred growth inhibition assay was used to determine the antimicrobial activities of coagulase- negative Staphylococcus (CoNS) species, including S. capitis and S. lugdunensis, which were determined to have novel genes for Biosynthetic Gene Clusters (BGS). Two species competition (co-culture) was explored to simulate the competition environment among species isolated from human skin and those species with novel BGS. Experimental evolution of interference competition was used to identify mutations selected during co-culture. Illumina platform genome resequencing of S. aureus clones identified multiple single nucleotide polymorphisms (SNPs) including several candidate resistance genes. In co-culture with the unidentified antimicrobial producer S. capitis 47, S. aureus strains SH1000 and 184 evolved mutations in the repressor gene cro/cI that was previously demonstrated to regulate an efflux transporter, supporting that S. aureus might use this efflux pump system to survive this antimicrobial activity in competition with other producer species. During serial passages of S. aureus SH1000 and 184 strains, further mutations were selected in the agr and sigB genes that reduced pigment production. In a separate coculture investigation with the epifadin antimicrobial producer S. epidermidis IVK83, S. aureus USA300 showed experimentally evolved resistance with mutation in the two-component system (TCS), desK gene. The DesKR TCS was recently implicated in epifadin resistance during a study in our research group at Liverpool. This study extends our knowledge into the strain USA300. A further co-culture competition was performed with S. aureus USA300 and antimicrobial producer S. lugdunensis 1007. While confirming existing data that S. aureus could not evolve resistance to lugdunin but there were selected mutations that supported increased fitness. The S. aureus mutations identified in the Cro/CI repressor, DesKR TCS and those in response to a lugdunin producer indicate there are an array of mechanisms concerned with interspecific competition. Commensal bacteria are an important resource of molecules and antimicrobials to study for preventing staphylococcal infections.
The role of gamma oscillations in the modulation of memory consolidation by emotions
Creators: name: Kanta Chantzi, Vasiliki
Publisher: name: No Publisher Supplied
Year: 2019

description: Our everyday experiences, even for mundane events, can form long-lasting memories. While newly formed memories are labile at first, with time they may become permanent and resistant to forgetting. This process is called memory consolidation. For declarative memories, consolidation is thought to involve interactions between the neocortex and hippocampus during offline states such as sleep. Besides strengthening with time, memory consolidation is also influenced by emotional arousal. The facilitating effect of emotions on consolidation is mediated by the basolateral amygdala (BLA) and its strong projections to both the hippocampus and neocortex. In contrast to the extensive investigations of the electrophysiological mechanisms supporting systems consolidation between the hippocampus and neocortex, there has not been a comparable advancement in our understanding of the BLA’s role. However, what is known is that the BLA generates robust gamma oscillations during emotional arousal, which can facilitate interregional interactions. In order to provide a unified understanding of memory consolidation, I examined how the consolidation of emotional experiences affects the interactions between the BLA, hippocampus and medial prefrontal cortex (mPFC), a neocortical area linked to consolidation. In particular, I studied how gamma-related activity is affected after emotional learning. I then directly tested whether gamma oscillations in the BLA support consolidation, by using real-time optogenetic manipulation of these oscillations in the post-training consolidation period. My results show that gamma oscillations mediate the emotional facilitation of memory consolidation.
Thermal ratchet effect in confining geometries
Creators: name: Holubec, Viktor
name: Ryabov, Artem
name: Yaghoubi, Mohammad Hassan
name: Varga, Martin
name: Khodaee, Ayub
name: Foulaadvand, M. Ebrahim
name: Chvosta, Petr
Publisher: name: arXiv
Year: 2017
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Stochastic model of the Feynman-Smoluchowski ratchet is proposed and solved using generalization of the Fick-Jacobs theory. The theory fully captures nonlinear response of the ratchet to the difference of heat bath temperatures. The ratchet performance is discussed using the mean velocity, the average heat flow between the two heat reservoirs and the figure of merit, which quantifies energetic cost for attaining a certain mean velocity. Limits of the theory are tested comparing its predictions to numerics. We also demonstrate connection between the ratchet effect emerging in the model and rotations of the probability current and explain direction of the mean velocity using simple discrete analogue of the model.
Feedback by Massive Black Holes in Dwarf Galaxies
Creators: name: Silk, Joseph
Publisher: name: arXiv
Year: 2017
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Could there be intermediate mass black holes in essentially all old dwarf galaxies? I argue that current observations of Active Galactic Nuclei in dwarfs allow such a radical hypothesis which provides early feedback and potentially provides a unifying explanation for many if not all of the apparent dwarf galaxy anomalies, such as the abundance, core-cusp, "too big to fail", ultra-faint and baryon-fraction issues. I describe the supporting arguments, which are largely circumstantial in nature, and discuss a number of tests. There is no strong motivation for modifying the nature of cold dark matter in order to explain any of the dwarf galaxy "problems".
description: 6 pages, ApJL submitted
Resonances at very low temperature for the reaction D$_2$+H
Creators: name: Simbotin, I.
name: Côté, R.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: We present numerical results for rate coefficients of reaction and vibrational quenching in the collision of H with D$_2(v,j)$ at cold and ultracold temperatures. We explore both ortho-D$_2(j\!=\!0)$ and para-D$_2(j\!=\!1)$ for several initial vibrational states $(v\leq 5)$, and find resonant structures in the energy range 0.01--10 kelvin, which are sensitive to the initial rovibrational state $(v,j)$. We compare the reaction rates for D$_2$+H with our previously obtained results for the isotopologue reaction H$_2$+D, and discuss the implications of our detailed study of this benchmark system for ultracold chemistry.
description: 12 pages, 7 figures
Induced parity-odd effective action for a Dirac field on $S^2 \times S^1$
Creators: name: Fosco, C. D.
name: Schaposnik, F. A.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We evaluate the parity-odd part of the effective action due to massive Dirac fermions on a $S^2 \times S^1$ manifold, minimally coupled to an external Abelian gauge field. We do that for a special class of gauge-field configurations, which is specially suitable to the study of the behaviour of the fermionic determinant under large gauge field configurations, which are allowed by the space-time geometry.
description: 13 pages
Interactions between two C60 molecules measured by scanning probe microscopies
Creators: name: Hauptmann, Nadine
name: González, César
name: Mohn, Fabian
name: Gross, Leo
name: Meyer, Gerhard
name: Berndt, Richard
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: C60-functionalized tips are used to probe C60 molecules on Cu(111) with scanning tunneling and atomic force microscopy. Distinct and complex intramolecular contrasts are found. Maximal attractive forces are observed when for both molecules a [6,6] bond faces a hexagon of the other molecule. Density functional theory calculations including parameterized van der Waals interactions corroborate the observations.
description: 6 pages, 3 figures
Towards exascale real-time RFI mitigation
Creators: name: van Nieuwpoort, Rob V.
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We describe the design and implementation of an extremely scalable real-time RFI mitigation method, based on the offline AOFlagger. All algorithms scale linearly in the number of samples. We describe how we implemented the flagger in the LOFAR real-time pipeline, on both CPUs and GPUs. Additionally, we introduce a novel simple history-based flagger that helps reduce the impact of our small window on the data. By examining an observation of a known pulsar, we demonstrate that our flagger can achieve much higher quality than a simple thresholder, even when running in real time, on a distributed system. The flagger works on visibility data, but also on raw voltages, and beam formed data. The algorithms are scale-invariant, and work on microsecond to second time scales. We are currently implementing a prototype for the time domain pipeline of the SKA central signal processor.
description: 2016 Radio Frequency Interference (RFI2016) Coexisting with Radio Frequency Interference, Socorro, New Mexico, USA, October 2016
Risk Factors for Pneumonia in Children: A Rapid Survey
Creators: name: Mirasa, Yudied Agung
name: Sriwahyuni, Efi
name: Lestari, Evi Noerita
name: Hendriyanto, Hendriyanto
name: Eka, Ni Gusti Ayu
Publisher: name: La Trobe
Year: 2024
Subjects: classificationCode: 32
subject: Biomedical and clinical sciences
classificationCode: 4206
subject: Public health
classificationCode: 42
subject: Health sciences
subject: FOS: Health sciences

description: Background: Pneumonia is the leading cause of infection-related death in children globally. East Java, Indonesia, is one of the provinces with the discovery achievement of pediatric pneumonia cases under 70%. Nganjuk Regency, located in East Java, has low discovery achievement of pediatric pneumonia cases (34.64%). Nganjuk Regency also requires an up-to-date study to determine the current state of pneumonia risk factors. Objective: This study aimed to examine the occurrence of pneumonia in toddlers and its risk factors in Nganjuk Regency East Java, Indonesia. Methods: The design of this study was a cross-sectional using a rapid survey. The participants of this study were 210 housewives or other adult household members having children under five in Nganjuk Regency. The study procedure began by collecting data from seven districts wherein each district comprised 30 houses that were chosen purposely. Data analysis was carried out using bivariate and multivariate analysis. The data were analyzed using the statistical software STATA. Results: This study revealed that 18 (7.96%) toddlers had developed pneumonia. The main risk factors for pneumonia among toddlers in Nganjuk Regency were the nutritional status of toddlers (OR=6.787; 95%CI=1.417- 32.525; p=0.017), house cleaning (OR=3.381; 95%CI=1.160-9.851; p=0.026), and room occupancy density (OR=4.191; 95%CI=1.371-12.809; p=0.012). Conclusion: The incidence of toddler pneumonia can be reduced by educating mothers about pneumonia and its risk factors, monitoring toddler growth and nutritional status, and conducting routine surveillance of toddler pneumonia alongside sanitation inspections.
Emotional Experience and Quality of Life Following a Spinal Cord Injury: an Interpretative Phenomenological Analysis, 2007-2008
Creators: name: Allan, D.
name: Dickson, A.
name: O’Carroll, R.
Publisher: name: UK Data Service
Year: 2016

description: The primary objective of this research project was to establish what it means to live with a Spinal Cord Injury (SCI) on the basis of the lived experiences of the injured individual and partner caregiver. Seventeen semi-structured interviews were conducted with individuals with a SCI. Eleven in-depth semi-structured interviews were conducted with partner caregivers of individuals with a SCI. The interviews were transcribed verbatim and were subjected to Interpretative Phenomenological Analysis (IPA).

 On the whole, the injured individuals praised their health care but they did indicate a need for psychological preparation for the sexual difficulties, incontinence issues and biographical disruption that they experienced in their post-injury lives. A radical loss of control and a dependency on other people were reported. Collectively, these experiences led to what was described as an "emotional rollercoaster" defined by feelings of frustration, entrapment and depression. Other people’s reactions to the acquired disability further contributed to emotional distress. Acceptance, downward comparison and social support buffered the devastating impact of SCI and the impact it had on participants’ quality of life.

 The partner caregivers reported feelings of anxiety related to prolonged separation from the injured person during their stay in hospital and also to their caregiver duties. Their new caregiver role brought burdensome responsibilities, financial concerns and a loss of freedom, spontaneity and biographical disruption. A dramatic shift in the marital relationship and a shift in role from lover and partner to purely caregiver resulted in subsequent feelings of entrapment, despair and suicidal ideation for some participants. A loss or change in identity ensued and overall, the impact of caregiving had a detrimental impact on the participants’ quality of life. Accepting the new caregiver role, social support and taking "time out" from the caregiver role were all reported to buffer the effects of caregiver burden.
Presentation: Text Annotation Automation for Hate Speech Detection using SVM-classifier based on Feature Extraction
Creators: name: Nur Heri Cahyana, , ,
name: Agus Sasmito Aribowo
name: Shoffan Saifullah
name: Fauziah, Yuli
Publisher: name: Zenodo
Year: 2022

description: This material has presented on 1st International Conference on Advanced Research in Engineering and Technology. October 25, 2022
Properties of the Intergalactic Magnetic Field Constrained by Gamma-ray Observations of Gamma-Ray Bursts
Creators: name: Veres, P.
name: Dermer, C. D.
name: Dhuga, K. S.
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: The magnetic field in intergalactic space gives important information about magnetogenesis in the early universe. The properties of this field can be probed by searching for radiation of secondary e$^+ $e$^-$ pairs created by TeV photons, that produce GeV range radiation by Compton-scattering cosmic microwave background (CMB) photons. The arrival times of the GeV "echo" photons depend strongly on the magnetic field strength and coherence length. A Monte Carlo code that accurately treats pair creation is developed to simulate the spectrum and time-dependence of the echo radiation. The extrapolation of the spectrum of powerful gamma-ray bursts (GRBs) like GRB 130427A to TeV energies is used to demonstrate how the IGMF can be constrained if it falls in the $10^{-21}$ - $10^{-17}$ G range for 1 Mpc coherence length.
description: 8 pages, 6 figures
Improving DL-MU-MIMO Performance in IEEE 802.11ac Networks through Decoupled Scheduling
Creators: name: Kosek-Szott, Katarzyna
Publisher: name: arXiv
Year: 2017
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: The IEEE 802.11ac standard introduces new downlink multi-user MIMO (DL-MU-MIMO) transmissions to up to four users in order to increase spatial reuse in wireless local area networks (WLANs). We argue that even better WLAN per- formance can be achieved by slightly modifying the DL-MU-MIMO scheduling. To this end we propose a new queuing mechanism based on the decoupling of EDCA and DL-MU-MIMO scheduling (DEMS) to avoid head-of-line blocking. We show that DEMS outperforms traditional 802.11ac scheduling based on first in, first out transmission queues. The improvement is shown in terms throughput achieved with: (a) more efficient channel usage, (b) increased probability of transmission of high priority traffic, and (c) decreased competition between frames destined to distinct users.
description: Manuscript accepted for publication in Springer Wireless Networks
Higher-Order Scheme-Independent Series Expansions of $γ_{\barψψ,IR}$ and $β'_{IR}$ in Conformal Field Theories
Creators: name: Ryttov, Thomas A.
name: Shrock, Robert
Publisher: name: arXiv
Year: 2017
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study a vectorial asymptotically free gauge theory, with gauge group $G$ and $N_f$ massless fermions in a representation $R$ of this group, that exhibits an infrared (IR) zero in its beta function, $β$, at the coupling $α=α_{IR}$ in the non-Abelian Coulomb phase. For general $G$ and $R$, we calculate the scheme-independent series expansions of (i) the anomalous dimension of the fermion bilinear, $γ_{\barψψ,IR}$, to $O(Δ_f^4)$ and (ii) the derivative $β' = dβ/dα$, to $O(Δ_f^5)$, both evaluated at $α_{IR}$, where $Δ_f$ is an $N_f$-dependent expansion variable. These are the highest orders to which these expansions have been calculated. We apply these general results to theories with $G={\rm SU}(N_c)$ and $R$ equal to the fundamental, adjoint, and symmetric and antisymmetric rank-2 tensor representations. It is shown that for all of these representations, $γ_{\barψψ,IR}$, calculated to the order $Δ_f^p$, with $1 \le p \le 4$, increases monotonically with decreasing $N_f$ and, for fixed $N_f$, is a monotonically increasing function of $p$. Comparisons of our scheme-independent calculations of $γ_{\barψψ,IR}$ and $β'_{IR}$ are made with our earlier higher $n$-loop values of these quantities, and with lattice measurements. For $R=F$, we present results for the limit $N_c \to \infty$ and $N_f \to \infty$ with $N_f/N_c$ fixed. We also present expansions for $α_{IR}$ calculated to $O(Δ_f^4)$.
description: 40 pages, latex, 12 figures
title:  Television, Low Self-Control, and Deviance: Examining Basic Elements of Gottfredson and Hirschi's General Theory of Crime
Creators: name: Mina Jr., Moises O.
Publisher: name: Old Dominion University
publisherIdentifier: https://ror.org/04zjtrb98
publisherIdentifierScheme: ROR
Year: 1999

description: In a secondary analysis of data from the National Longitudinal Survey of Youth (NLSY), this study examines the basic concepts of Gottfredson and Hirschi's general theory of crime. A set of variables measured at ages 6-9 was used to operationally define the concepts of self-control, parenting, and deviance. The study tests for empirical associations between self-control, deviance, and parenting. Also, television viewing is introduced as a possible cause of low self-control. Age, race, and gender are included as statistical controls. Models of self-control and deviance were developed to analyze these relationships. Results found qualified support for the existence of significant associations between self-control and the television viewing and parenting variables. A moderate correlation between self-control and deviance indicates support for Gottfredson and Hirschi's theory of criminality. Suggestions are offered on data gathering and variable selection for the benefit of future research on the subject.
In vitro protease cleavage and computer simulations reveal the HIV-1 capsid maturation pathway
Creators: name: Ning, Jiying
name: Erdemci-Tandogan, Gonca
name: Yufenyuy, Ernest L
name: Wagner, Jef
name: Himes, Benjamin A
name: Zhao, Gongpu
name: Aiken, Christopher
name: Zandi, Roya
name: Zhang, Peijun
Publisher: name: arXiv
Year: 2016
Subjects: subject: Biological Physics (physics.bio-ph)
subject: Subcellular Processes (q-bio.SC)
subject: FOS: Physical sciences
subject: FOS: Biological sciences

description: HIV-1 virions assemble as immature particles containing Gag polyproteins that are processed by the viral protease into individual components, resulting in the formation of mature infectious particles. There are two competing models for the process of forming the mature HIV-1 core: the disassembly and de novo reassembly model and the non-diffusional displacive model. To study the maturation pathway, we simulate HIV-1 maturation in vitro by digesting immature particles and assembled virus-like particles with recombinant HIV-1 protease and monitor the process with biochemical assays and cryoEM structural analysis in parallel. Processing of Gag in vitro is accurate and efficient and results in both soluble capsid protein and conical or tubular capsid assemblies, seemingly converted from immature Gag particles. Computer simulations further reveal probable assembly pathways of HIV-1 capsid formation. Combining the experimental data and computer simulations, our results suggest a sequential combination of both displacive and disassembly/reassembly processes for HIV-1 maturation.
Electrical and photoelectrical characteristic investigation of a new generation photodiode based on bromothymol blue dye
Creators: name: Imer, A Gencer
name: Tombak, A
name: Korkut, A
Publisher: name: arXiv
Year: 2017
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: Bromothymol blue (BTB) with the molecular formula of C27H28Br2O5S was grown onto p-Si substrate to fabricate heterojunction by spin coating technique. The current voltage (I-V) measurements of diode were carried out in dark and under different illumination intensity at room temperature. The photoelectrical properties of heterojunction based on BTB were investigated using the illumination intensity dependent I-V data. The results showed that photo current of diode increases with the increase in light intensity. Also, the electrical parameters of device were determined via I-V, and capacitance- voltage (C-V), conductance-voltage (G-V) measurements at different frequencies. It is observed that the excess capacitance is created at low frequencies due to the contribution of interface states charge which can follow the alternative current signal to capacitance. It is stated that, both the electrical photoelectrical parameters of diode can be changed, and also the performance of the device could be affected by the organic thin film interlayer.
description: 9 pages, 7 figure, 2 table
A Critical Improvement On Open Shop Scheduling Algorithm For Routing In Interconnection Networks
Creators: name: Birmpilis, Stavros
name: Aslanidis, Timotheos
Publisher: name: arXiv
Year: 2017
Subjects: subject: Networking and Internet Architecture (cs.NI)
subject: FOS: Computer and information sciences

description: In the past years, Interconnection Networks have been used quite often and especially in applications where parallelization is critical. Message packets transmitted through such networks can be interrupted using buffers in order to maximize network usage and minimize the time required for all messages to reach their destination. However, preempting a packet will result in topology reconfiguration and consequently in time cost. The problem of scheduling message packets through such a network is referred to as PBS and is known to be NP-Hard. In this paper we have improved, critically, variations of polynomially solvable instances of Open Shop to approximate PBS. We have combined these variations and called the induced algorithm IHSA, Improved Hybridic Scheduling Algorithm. We ran experiments to establish the efficiency of IHSA and found that in all datasets used it produces schedules very close to the optimal. In addition, we tested IHSA with datasets that follow non-uniform distributions and provided statistical data which illustrates better its performance.To further establish the efficiency of IHSA we ran tests to compare it to SGA, another algorithm which when tested in the past has yielded excellent results.
High voltage assisted mechanical stabilization of single-molecule junctions
Creators: name: Gelbwaser-Klimovsky, David
name: Aspuru-Guzik, Alán
name: Thoss, Michael
name: Peskin, Uri
Publisher: name: arXiv
Year: 2017
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The realization of molecular-based electronic devices depends to a large extent on the ability to mechanically stabilize the involved molecular bonds, while making use of efficient resonant charge transport through the device. Resonant charge transport can induce vibrational instability of molecular bonds, leading to bond rupture under a bias voltage. In this work, we go beyond the wide-band approximation in order to study the phenomenon of vibrational instability in single molecule junctions and show that the energy-dependence of realistic molecule-leads couplings affects the mechanical stability of the junction. We show that the chemical bonds can be stabilized in the resonant transport regime by increasing the bias voltage on the junction. This research provides guidelines for the design of mechanically stable molecular devices operating in the regime of resonant charge transport.
Circumstellar discs: What will be next?
Creators: name: Kral, Quentin
name: Clarke, Cathie
name: Wyatt, Mark
Publisher: name: arXiv
Year: 2017
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: This prospective chapter gives our view on the evolution of the study of circumstellar discs within the next 20 years from both observational and theoretical sides. We first present the expected improvements in our knowledge of protoplanetary discs as for their masses, sizes, chemistry, the presence of planets as well as the evolutionary processes shaping these discs. We then explore the older debris disc stage and explain what will be learnt concerning their birth, the intrinsic links between these discs and planets, the hot dust and the gas detected around main sequence stars as well as discs around white dwarfs.
description: invited review; comments welcome (32 pages)
Simulating electric field interactions with polar molecules using spectroscopic databases
Creators: name: Owens, Alec
name: Zak, Emil J.
name: Chubb, Katy L.
name: Yurchenko, Sergei N.
name: Tennyson, Jonathan
name: Yachmenev, Andrey
Publisher: name: arXiv
Year: 2017
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: Ro-vibrational Stark-associated phenomena of small polyatomic molecules are modelled using extensive spectroscopic data generated as part of the ExoMol project. The external field Hamiltonian is built from the computed ro-vibrational line list of the molecule in question. The Hamiltonian we propose is general and suitable for any polar molecule in the presence of an electric field. By exploiting precomputed data, the often prohibitively expensive computations associated with high accuracy simulations of molecule-field interactions are avoided. Applications to strong terahertz field-induced ro-vibrational dynamics of PH$_3$ and NH$_3$, and spontaneous emission data for optoelectrical Sisyphus cooling of H$_2$CO and CH$_3$Cl are discussed.
description: 19 pages, 9 figures, 2 tables