Miracle-dz/UniFAR-FTUs huggingface dataset:
From Boltzmann to incompressible Navier–Stokes in Sobolev spaces with polynomial weight

We study the Boltzmann equation on the [Formula: see text]-dimensional torus in a perturbative setting around a global equilibrium under the Navier–Stokes linearization. We use a recent functional analysis breakthrough to prove that the linear part of the equation generates a [Formula: see text]-semigroup with exponential decay in Lebesgue and Sobolev spaces with polynomial weight, independently of the Knudsen number. Finally, we prove well-posedness of the Cauchy problem for the nonlinear Boltzmann equation in perturbative setting and an exponential decay for the perturbed Boltzmann equation, uniformly in the Knudsen number, in Sobolev spaces with polynomial weight. The polynomial weight is almost optimal. Furthermore, this result only requires derivatives in the space variable and allows to connect solutions to the incompressible Navier–Stokes equations in these spaces.
Serological and molecular investigation of canine influenza virus in Plateau State, Nigeria

Canine influenza is a highly contagious respiratory infection of dogs caused by the Influenza A Virus (IAV), characterized by cough, sneeze, nasal secretions, and inappetence. Infections can be mild, severe or fatal. Aquatic birds constitute a natural reservoir for IAV, which is transmitted to terrestrial birds, including poultry. IAV has also emerged in other mammalian species, including humans, swine, horses, and dogs. IAV epidemics in dogs are a recent development. Commonly detected Canine Influenza Virus (CIV) strains are A/H3N2 and A/H3N8 from avian and equine influenza, respectively. Nigeria’s agro-ecology witnessed widespread circulation of avian influenza since 2006, and recent outbreaks of equine influenza in 2018/2019 raise the possibility of inter-species transmission to dogs. To investigate canine Influenza in Plateau State, we collected 113 nasal swabs and 270 sera samples from dogs in clinics, live dog markets, and during dog vaccination campaigns. After extracting nucleic acid with the Qiagen kit, RT-PCR analysed swabs for the Influenza A matrix gene. Sera samples were screened by Enzyme-Linked Immunosorbent Assay before subtyping a cross-section for H3 antibody by Hemagglutination Inhibition. No matrix gene was amplified from extracted nucleic acid from the nasal swabs. Though few sera were reactive to influenza A nucleoprotein, none was positive for influenza A/H3. The H3N8 strain of equine influenza virus first caused an epidemic in dogs in 1999 in the United States. Subsequently, avian-origin H3N2 CIV emerged in dogs in China and South Korea in 2005. Past CIV epidemics arose from a single cross-species transmission of H3N8 subtype from a mammalian intermediate host and the H3N2 subtype from an avian reservoir. Even though this limited investigation did not detect CIV in Plateau State, the potential remains because of the persistent circulation of avian, swine, and equine Influenza in Nigeria, which requires more extensive virological and serological surveillance.
Ion Collection by a Conducting Sphere in a Magnetized or Drifting Collisional Plasma

Ion collection by dust grains and probes in plasmas with a neutral background is of interest in the study of both space and terrestrial plasmas, where charge-exchange collisions can play an important role in ion collection. Further, background drifts or magnetic fields can significantly affect the ion collection by and the potential structure near such objects, and should therefore also be included. These effects, however, are difficult to include in a theoretical treatment, and thus this problem lends itself to a computational approach. To be able to tackle problems with a neutral background, the 3D3v hybrid particlein-cell code SCEPTIC3D has been upgraded to include charge-exchange collisions. This required the development of a new Monte Carlo based reinjection scheme. The new reinjection scheme and other upgrades are described in detail, and the collisionless operation of the reinjection scheme is validated against the old SCEPTIC3D reinjection scheme, while its collisional operation is validated through comparisons with the reinjection scheme in SCEPTIC (2D). The new reinjection scheme can easily be modified to allow the injection of an almost arbitrary distribution function at the domain boundary, enabling future studies of the sensitivity of ion collection to the injected velocity distribution. Studies of ion collection in magnetized or drifting plasmas using the upgraded code extend earlier stationary, unmagnetized results, which showed an enhancement of ion current at intermediate collisionality. It is found that this enhancement is gradually suppressed with increasing background neutral drift speed, and is entirely absent for speeds above the ion sound speed. Adding a magnetic field rather than a neutral drift appears to in fact increase the collisional ion current enhancement. Thesis Supervisor: Ian H. Hutchinson Title: Professor of Nuclear Science and Engineering Thesis Reader: Jeffrey P. Freidberg Title: Emeritus Professor of Nuclear Science and Engineering
TeV–PeV NEUTRINO OSCILLATION OF LOW-LUMINOSITY GAMMA-RAY BURSTS

There is evidence that long-duration gamma-ray bursts (GRBs) originate from the core collapse of massive stars. When a jet punctures through the progenitor envelope, high-energy neutrinos can be produced by the reverse shock formed at the jet head. It is suggested that low-luminosity GRBs are possible candidates of this high-energy neutrino precursor up to ∼ PeV ? > scales. Before leaving the progenitor, these high-energy neutrinos must oscillate from one flavor to another with the matter effect in the envelope. Under the assumption of a power-law stellar envelope density profile &rgr; ∝ r − &agr; ? > with an index α, we study the properties of TeV–PeV neutrino oscillation. We find that adiabatic conversion is violated for these neutrinos so we calibrate the level crossing effect. The resonance condition is reached for different energies at different radii. We note that the effective mixing angles in matter for PeV ? > neutrinos are close to zero, so the transition probabilities from one flavor to another are almost invariant for PeV ? > neutrinos. We plot all the transition probabilities versus the energy of TeV–PeV neutrinos from the birth place to the surface of the progenitor. With an initial flavor ratio φ &ngr; e 0 : φ &ngr; &mgr; 0 : φ &ngr; τ 0 = 1 : 2 : 0 ? > , we plot how the flavor ratio evolves with energy and distance when neutrinos are still in the envelope, and we find the ratio when they reach the Earth. For PeV ? > neutrinos, the ratio is always φ &ngr; e : φ &ngr; &mgr; : φ &ngr; τ ≃ 0.30 : 0.37 : 0.33 ? > on Earth. In addition, we discuss the dependence of the flavor ratio on energy and α and find a good result. This dependence may provide a promising probe of the progenitor structure.
The IRX-β dust attenuation relation in cosmological galaxy formation simulations

We utilise a series of high-resolution cosmological zoom simulations of galaxy formation to investigate the relationship between the ultraviolet (UV) slope, beta, and the ratio of the infrared luminosity to UV luminosity (IRX) in the spectral energy distributions (SEDs) of galaxies. We employ dust radiative transfer calculations in which the SEDs of the stars in galaxies propagate through the dusty interstellar medium. Our main goals are to understand the origin of, and scatter in the IRX-beta relation; to assess the efficacy of simplified stellar population synthesis screen models in capturing the essential physics in the IRX-beta relation; and to understand systematic deviations from the canonical local IRX-beta relations in particular populations of high-redshift galaxies. Our main results follow. Galaxies that have young stellar populations with relatively cospatial UV and IR emitting regions and a Milky Way-like extinction curve fall on or near the standard Meurer relation. This behaviour is well captured by simplified screen models. Scatter in the IRX-beta relation is dominated by three major effects: (i) older stellar populations drive galaxies below the relations defined for local starbursts due to a reddening of their intrinsic UV SEDs; (ii) complex geometries in high-z heavily star forming galaxies drive galaxies toward blue UV slopes owing to optically thin UV sightlines; (iii) shallow extinction curves drive galaxies downward in the IRX-beta plane due to lowered NUV/FUV extinction ratios. We use these features of the UV slopes of galaxies to derive a fitting relation that reasonably collapses the scatter back toward the canonical local relation. Finally, we use these results to develop an understanding for the location of two particularly enigmatic populations of galaxies in the IRX-beta plane: z~2-4 dusty star forming galaxies, and z>5 star forming galaxies.
Occurrence rate of extreme magnetic storms

We investigate the occurrence rate of magnetic storms at the Earth. During the first part of our study, the standard and integral distribution functions of magnetic storm value (minimal Dst index) for the period 1963–2012 are analyzed and results show that the standard and integral distribution functions have power law tails with indexes γ=−4.4 and −3.4, respectively. During the second part, statistical analysis of occurrence rate of magnetic storms induced by different types of interplanetary drivers is made using OMNI data for the period 1976–2000. Using our catalog of large‐scale types of solar wind streams, we study storms induced by interplanetary coronal mass ejections (ICMEs) (separately magnetic clouds (MCs) and Ejecta) and both types of compressed regions: corotating interaction regions (CIRs) and Sheaths. For these types of drivers, we calculate the integral probabilities of storms with minimum Dst ≤−50, −70, −100, −150, and −200 nT. The highest probability in this interval of Dst is observed for MCs, with the probabilities for other drivers being 3–10 times lower. Extrapolation of these results to extreme storms shows that a magnetic storm as large as the Carrington storm in 1859 with Dst=−1760 nT is observed on the Earth with frequency not higher than one event during ∼500 years.
A matrix-algebraic approach to linear hybrid interference cancellation in CDMA

In this paper we consider a matrix algebraic approach to a linear hybrid interference canceller (HIC). This scheme is a combination of parallel and successive cancellation. It is shown that both the single-stage and multistage linear HIC can be expressed as a one-shot linear matrix filter on the received chip-matched filtered signal vector. It is proved that if the linear HIC converges, it will converge to the decorrelating detector. The eigenvalue conditions for the convergence of the multistage schemes are then derived. It is shown by simulation that the linear HIC with four or more groups at every stage can converge. When there are only two groups, however, the detector may not always converge. In this case, a weighted cancellation structure is suggested to ensure convergence. Simulation results show that if the detector converges, the minimum BER is generally obtained before the convergence is achieved, and that the weighted structure has smaller minimum BER than the non-weighted one.
Theoretical study of the Ξ(1620) and Ξ(1690) resonances in Ξc→π+MB decays

Nonleptonic weak decays of Ξc into π+ and a meson (M)-baryon (B) final state, MB, are analyzed from the viewpoint of probing S=−2 baryon resonances, i.e., Ξ(1620) and Ξ(1690), of which spin-parity and other properties are not well known. We argue that the weak decay of Ξc is dominated by a single quark-line diagram, preferred by the Cabibbo-Kobayashi-Maskawa coefficient, color recombination factor, the diquark correlation, and the kinematical condition. The decay process has an advantage of being free from meson resonances in the π+M invariant mass distribution. The invariant mass distribution of the meson-baryon final state is calculated with three different chiral unitary approaches, assuming that the Ξ(1620) and Ξ(1690) resonances have JP=1/2−. It is found that a clear peak for the Ξ(1690) is seen in the πΞ and K¯Λ spectra. We also suggest that the ratios of the πΞ,K¯Λ, and K¯Σ final states are useful to distinguish whether the peak is originated from the Ξ(1690) resonance or it is a K¯Σ threshold effect.
Relative Entropy and Torsion Coupling

Based on the the geometric realization of entanglement entropy via Ryu-Takayanagi formula, in this work we evaluate the relative entropy for the holographic deformed CFT dual to the torsion gravity coupled to the fermions of nonzero vev in the Einstein-Cartan formulation. We find that the positivity and monotonicity of the relative entropy imposes constraint on the strength of axial-current coupling, fermion mass and equation of state. Our work is the first example to demonstrate the nontrivial constraint on the bulk gravity theory from the quantum information inequalities. Especially, this constraint is beyond the symmetry action principle and should be understood as the unitarity constraint. This talk is based on the work [1] of the authors.
Feels Like Going Backwards: Assessing Income Convergence with a Long-Run Forecasting Approach

Relying on low frequency econometric methods, a new simple method to assess international income convergence is introduced. It implements the long-run forecasting deﬁnition and discards short and medium-term information contents of the data as these may produce misleading evidence. Robustness to non-stationarities is achieved using ﬁrst diﬀerences of logged per capita incomes. Application to a selected sample of 67 diﬀerent countries, including only one low-income country, provides scant support to the hypothesis. Even for a 120-year horizon, almost 4/5 or 80% of the population of the (positively biased selected) sample is forecast to still live in countries signiﬁcantly lagging behind the leader.
Computational Framework for Light Field Microscopy Simulation and Optimization

Light field microscopy (LFM) is the key technology for optically imaging the neuron activity in live animal's brain. However, there is still no computational framework that could provide an unified simulation and optimization process. The presented work proposed and demonstrated a computational simulation and optimization framework for LFM systems. The proposed framework consists of three main modules: forward model, backward model, and the optimizer. The paper comprehensively introduces the theory background and implementation details behind each module. The expecting hope of the developed computational framework is to let users not from computation side could still quickly prototype and further optimize their LFM optical design and reconstruction model. Furthermore, the paper also contributes in the taxonomy for current LFM systems, the microlens array optimization methods, and the optimization pipelines based on the differentiability of the models.
University of Birmingham A synergistic effect of albumin and H2O2 accelerates corrosion of Ti6Al4V

The synergistic effect of albumin and H 2 O 2 on corrosion of titanium alloy Ti6Al4V in physiological saline was investigated with long-term immersion tests and electrochemical methods. It was found that in the presence of both albumin and H 2 O 2 , the rate of metal release in immersion tests was far higher than in the presence of either species alone. Electrochemical polarisation curves and potentiostatic tests showed that H 2 O 2 increased both the rates of the anodic and cathodic reactions, while albumin significantly decreased the rate of the cathodic reaction and slightly decreased the rate of the anodic reaction. The synergistic effect of albumin and H 2 O 2 during immersion tests was attributed to the effect of adsorption of albumin in lowering the rate of the cathodic reaction and thus lowering the open circuit potential into the active region of titanium where complexation by H 2 O 2 increased the corrosion rate. The corrosion attack was found to be greater in the β-phase of the alloy. The findings suggest that current standard tests in physiological or phosphate-buffered saline may underestimate the rate of corrosion in the peri-implant environment, in which albumin is the predominant protein, and reactive oxygen species such as H 2 O 2 can occur as a result of inflammatory reactions in response to surgery, infection, or implant corrosion products.
Open Research Online Risk of work-related violence in England and Wales

Background There is an urgent need to address high levels of work-related violence (WRV) in Britain to improve the workplace experience of both employers and employees. Aims This study specifically explores prevalence rates of work-related violence assaults (WRVAs) for staff at high risk that have supervisor responsibilities and work full-time. Methods Five years of data were used for analysis from the Crime Survey of England and Wales (CSEW). Data were filtered for victims of crime from a working population in Britain. Results Forty-four per cent of respondents who are supervisors and have full-time jobs report that they had been victims of WRVAs. This figure is higher than other previous studies of WRV. Conclusions The current study provides further alternative evidence to support high prevalence rates of WRV by selecting for analysis specific work characteristics data that are strongly associated with WRV (super-visor responsibilities and full-time work). It is therefore recommended that future work explores different means of intervention for organizations to implement within the workplace to reduce WRV and protect workers from harm.
artículo dE iNVEstigaciÓN s ElF - EstEEm aNd s uicidal i dEatioN iN P akistaNi u NdErgraduatEs

The main purpose of the study was to assess the relationship between self-esteem and suicidal ideation in Pakistani undergraduates ( N = 600). Participants’ ages ranged from 17 to 25 years ( M =20.26, SD = 1.6) with 50% males and 50% females. A Structural Equation Modeling approach was used to analyse the data. All fit indices were examined on measurement level. Relationships between three latent variables: positive self-esteem, negative self-esteem, and suicidal ideation were assessed on structural level. Results revealed that students with negative self-esteem were more prone towards suicidal ideation ( β = .15, p < .001). Moreover, those students who were having positive self-esteem were less likely indicating suicide ideation which suggested that positive self-esteem is a protective factor against suicidal ideation ( β = -.10, p < .05) among undergraduates.
Mixing and CP violation in the B0s meson system at CDF

Cette these resume le travail sur la mesure des parametres qui definissent le systeme des meson Bs. Une premiere partie est consacree a l'observation des oscillations des mesons Bs caracterisees par la frequence de melangeΔms. Cette derniere a ete mesuree au travers des desintegrations hadroniques et semi-leptoniques des mesons Bs produits au Tevatron et reconstruits dans l'experience CDF, pour une luminosite integree de 1 fb-1. L'ensemble de ces travaux a conduit a la mesure Δms= 17. 77 ± 0. 10(stat)± 0. 07(syst) ps-1, avec une pertinence de 5σ et permettant d'extraire le rapport des elements de la matrice CKM |Vts|2/|Vtd|2 =0. 2060±0. 0007(exp)+0. 0081-0. 0060(theory). La deuxieme partie est consacree a la premiere analyse pour evaluer, via des evenements Bs -> J/ΨΦ equivalent a 1. 35 fb-1, la phase de la violation CP 2βs, et la difference de largeur, ΔΓs, en identifiant la saveur des mesons Bs produits a l'origine. L'ensemble de ces donnees a permis de d'etablir une region de confiance selon le critere de Feldman-Cousins dans le plan 2βs-ΔΓs. En considerant les valeurs de 2βs et ΔΓs predites par le Modele Standard, la probabilite de deviation par rapport aux donnees experimentales est de 15%, soit une deviation standard Gaussienne de 1. 5σ.
The Tayler instability at low magnetic Prandtl numbers: Chiral symmetry breaking and synchronizable helicity oscillations

The current-driven, kink-type Tayler instability (TI) is a key ingredient of the Tayler-Spruit dynamo model for the generation of stellar magnetic fields, but is also discussed as a mechanism that might hamper the up-scaling of liquid metal batteries. Under some circumstances, the TI involves a helical flow pattern which goes along with some alpha effect. Here we focus on the chiral symmetry breaking and the related impact on the alpha effect that would be needed to close the dynamo loop in the Tayler-Spruit model. For low magnetic Prandtl numbers, we observe intrinsic oscillations of the alpha effect. These oscillations serve then as the basis for a synchronized Tayler-Spruit dynamo model, which could possibly link the periodic tidal forces of planets with the oscillation periods of stellar dynamos.
Stabilizer Codes and Quantum Error Correction

Controlling operational errors and decoherence is one of the major challenges facing the field of quantum computation and other attempts to create specified many-particle entangled states. The field of quantum error correction has developed to meet this challenge. A group-theoretical structure and associated subclass of quantum codes, the stabilizer codes, has proved particularly fruitful in producing codes and in understanding the structure of both specific codes and classes of codes. I will give an overview of the field of quantum error correction and the formalism of stabilizer codes. In the context of stabilizer codes, I will discuss a number of known codes, the capacity of a quantum channel, bounds on quantum codes, and fault-tolerant quantum computation.
Phase Transitions in Combinatorial Optimization Problems - Basics, Algorithms and Statistical Mechanics

Preface. 1 Introduction. 1.1 Two examples of combinatorial optimization. 1.2 Why study combinatorial optimization using statistical physics? 1.3 Textbooks. Bibliography. 2 Algorithms. 2.1 Pidgin Algol. 2.2 Iteration and recursion. 2.3 Divide-and-conquer. 2.4 Dynamic programming. 2.5 Backtracking. Bibliography. 3 Introduction to graphs. 3.1 Basic concepts and graph problems. 3.2 Basic graph algorithms. 3.3 Random graphs. Bibliography. 4 Introduction to complexity theory. 4.1 Turing machines. 4.2 Church's thesis. 4.3 Languages. 4.4 The halting problem. 4.5 Class P. 4.6 Class NP. 4.7 Definition of NP-completeness. 4.8 NP-complete problems. 4.9 Worst-case vs. typical-case complexity. Bibliography. 5 Statistical mechanics of the Ising model. 5.1 Phase transitions. 5.2 Some general notes on statistical mechanics. 5.3 The Curie-Weiss model of a ferromagnet. 5.4 The Ising model on a random graph. Bibliography. 6 Algorithms and numerical results for vertex covers. 6.1 Definitions. 6.2 Heuristic algorithms. 6.3 Branch-and-bound algorithm. 6.4 Results: Covering random graphs. 6.5 The leaf-removal algorithm. 6.6 Monte Carlo simulations. 6.7 Backbone. 6.8 Clustering of minimum vertex covers. Bibliography. 7 Statistical mechanics of vertex covers on a random graph. 7.1 Introduction. 7.2 The first-moment bound. 7.3 The hard-core lattice gas. 7.4 Replica approach. Bibliography. 8 The dynamics of vertex-cover algorithms. 8.1 The typical-case solution time of a complete algorithm. 8.2 The dynamics of generalized leaf-removal algorithms. 8.3 Random restart algorithms. Bibliography. 9 Towards new, statistical-mechanics motivated algorithms. 9.1 The cavity graph. 9.2 Warning propagation. 9.3 Belief propagation. 9.4 Survey propagation. 9.5 Numerical experiments on random graphs. Bibliography. 10 The satisfiability problem. 10.1 SAT algorithms. 10.2 Phase transitions in random K-SAT. 10.3 Typical-case dynamics of RandomWalkSAT. 10.4 Message-passing algorithms for SAT. Bibliography. 11 Optimization problems in physics. 11.1 Monte Carlo optimization. 11.2 Hysteric optimization. 11.3 Genetic algorithms. 11.4 Shortest paths and polymers in random media. 11.5 Maximum flows and random-field systems. 11.6 Submodular functions and free energy of Potts model. 11.7 Matchings and spin glasses. Bibliography. Index.