Miracle-dz/UniFAR-FTUs huggingface dataset:
Solar structure models

The Sun is a unique object in stellar evolution due to our unprecedent insight on its internal processes. We will illustrate in this review how the transition between a static vision to a more dynamical vision modifies the addressing questions on the solar radiative zone. Neutrinos and acoustic modes have first scrutinized the microscopic properties of the solar radiative plasma. Today, stimulated by the internal rotation profile determination, new questions emerge on the angular momentum transport by rotation, internal waves and on the role of magnetic fields to get access to the dynamical motions of this important region of the Sun. We will give some examples which demonstrate that the Sun is not yet under control.
Pre-treatment Drug Resistance Could Impact the 96-Week Antiretroviral Efficacy in Treatment-Naive HIV-1–Infected Patients in Guangdong, China

Abstract Background With the high prevalence of pre-treatment drug resistance (PDR) and the potential impact to the virological inhibition, the detection of PDR was particularly necessary. This study aimed to determine the prevalence of PDR in Guangdong, China, and its impact on antiretroviral therapy (ART) in treatment-naive HIV patients. Methods A retrospective cohort study was conducted. A total of 1936 HIV-1–infected treatment-naive patients in the clinic of the infectious department, Guangzhou Eighth People’s Hospital, between August 2018 and December 2019 were assayed for PDR mutations before initiating ART. Patients with PDR mutations (PDR arm) were screened and compared with those without drug-resistant mutations (non-PDR arm). The rate of HIV-1 virologic failure (VF) and CD4+ T-cell counts of the 2 arms were compared at the 96th week after ART to evaluate the impact of PDR on the efficacy of ART. Results Pretreatment drug resistance was detected in 125 cases (6.46%) from the 1936 enrolled participants, most of which were resistant to non-nucleoside reverse transcriptase inhibitors (64.00%, 80/125). One hundred and eight of 125 completed the follow-up of 96 weeks (PDR arm). In this cohort, 52 patients whose ART regimen containing the resistant drug were grouped as con-PDR arm, and the remaining 56 patients whose ART regimen did not contain the resistant drug were grouped as non- con-PDR arm. A total of 125 patients without PDR were randomly selected as the control group (non-PDR arm), 112 of whom had completed the 96-week follow-up. At the 96th week after ART initiation, 7 patients (6.5%, 7/108) in the PDR arm and 1 patient (0.9%, 1/112) in the non-PDR arm developed VF, exhibiting a significant difference (χ2 = 4.901, P = 0.029). Meanwhile, 3 patients (5.8%, 3/52) in the con-PDR arm developed VF; the rate was also higher than that in the non-PDR arm, but without a significant difference (χ2 = 3.549, P = 0.095). The CD4+ T-cell count in the non-PDR arm increased more than the PDR arm (386.6 vs. 319.1 cells/μL, t = 2.448, P = 0.015) or the con-PDR arm (386.6 vs. 325.1 cells/μL, t = 1.821, P = 0.070) at 12 weeks after ART. However, no significant differences were observed in the CD4+ T-cell count from the 24th week after ART onward. Conclusions Pretreatment drug resistance was moderately prevalent in Guangdong, China, and could affect the antiretroviral efficacy during a 96-week observation period, indicating the need to closely monitor PDR before ART initiation.
Tidal stripping and accretion in clusters of galaxies with smoothly distributed missing mass

Results are reported from simulations of the alterations in tidal stripping and tidal accretion caused by the presence of smoothly distributed missing mass (background) in Virgo-like clusters of galaxies. The simulations considered the collisional interactions of two galaxies treated as Schuster's spheres, one containing 170 test particles. The spheres were surrounded with either a mass equal to the total galactic mass or to nine times the galactic mass, or with no background exerting gravitational force. The presence of the background significantly decreased mass exchanges and losses. The implications the results have for simulations of collisions between galaxies are discussed. 30 references.
Unsteady Flow Analysis of a Multi-Element Airfoil Using Lattice Boltzmann Method

High-lift devices employed onmodern aircraft are significant contributors to overall airframe noise. In this paper, a lattice Boltzmannmethodwith a very large eddy simulation approach is applied to computationally investigate the aerodynamic and aeroacoustic behavior of the flow around a generic high-lift configuration (three-element airfoil) at low Mach number. Three-dimensional time-dependent nearly incompressible simulations were conducted at different angles of attack to capture the instantaneous andmeanflowfields around the airfoil, previously predicted by Navier–Stokes studies. The computed mean flow results showed good agreement with existing experimental and numerical data, which include the pressure distributions around the elemental surfaces and the time-averagedmean flowfield within the slat cove. As a major objective of the present study, the unsteady flow simulations were used to capture the slat cove unsteadiness, a source of both broadband and narrowband noise. In particular, the effect of angle of attack on the shear layer emanating from the slat cusp, slat trailing-edge vortex shedding, convection, and reattachment of vortical structures near the slat gap were explored by the present simulations. Consequently, the acoustic implications of such complex unsteady flow phenomenon within the slat cove were explained and discussed in detail.
AGN and Host Galaxies in the COSMOS Survey

Abstract The Cosmological Evolution Survey (COSMOS) is a unique tool for studying low level AGN activity and the co-evolution of galaxies and supermassive black holes. COSMOS involves the largest contiguous region of the sky ever imaged by HST; it includes very complete multiwavelength coverage, and the largest joint samples of galaxy and AGN redshifts in any deep survey. The result is a search for AGN with low black hole mass, low accretion rates, and levels of obscuration that can remove them from optical surveys. A complete census of intermediate mass black holes at redshifts of 1 to 3 is required to tell the story of the co-evolution of galaxies and their embedded, and episodically active, black holes.
Recursive Differential Systems in Nonlinear Mechanics

The classical strength of materials for beams is represented through the first two terms of the asymptotic expansion of the solution of Navier’s equations. The method of asymptotic expansions with respect to the inverse of the slenderness of the beam permits us to obtain an approximate solution of Saint-Venant’s problem. For the elasticity of the second order, the displacement field is obtained as the sum of a series, the general term of which at the nth order is the solution of a differential recursive system. We presently propose a general way of solving this kind of system. The exact solution is given explicitly in the case of a slender field (beam).
Biophysical characterization of hematopoietic cells from normal and leukemic sources with distinct primitiveness

This letter reported the biophysical characterization of immunophenotypically distinct hematopoietic cells from normal and leukemic sources, through manipulation with optical tweezers at single cell level. The results show that the percentage of cells that are stretchable and their deformability are significantly higher in the more primitive cell populations. This study provides the evidence that normal and leukemic hematopoietic cell populations with distinct primitiveness exhibit differential biophysical properties. These findings raise a hypothesis that the high deformability may be related to the unique functions and activities of primitive hematopoietic cells.
Efficient computation of lattice Green's functions for models with nearest-neighbour hopping

We show that for models with nearest-neighbour (nn) hopping, the lattice Green's functions can be calculated without the need to perform integrals. Our method applies to rectangular, triangular and honeycomb lattices in two dimensions, and to simple, face-centered and body-centered lattices in three dimensions. External magnetic fields can be dealt with trivially. As an example, we show that our method works for any ratio ϕ/ϕ0 of the magnetic flux through the unit cell, i.e. irrespective of the change in the size of the magnetic unit cell. Other straightforward generalizations are to models with multiple orbitals per site, with any spin-orbit coupling, on-site disorder, and any combinations thereof. The method works equally well in the presence of surfaces. In all cases, accurate values for large distances can be obtained very efficiently and without finite-size effects. The relationship to other computational methods is also analyzed.
Adaptive state estimation for systems with unknown noise covariances

An adaptive scheme is proposed for obtaining the steady-state Kalman gain matrix for o discrete-time system without a priori knowledge of the noise covariance matrices. It is based on combining an algorithm proposed recently by Carew and Belanger with an algorithm based on stochastic approximation. Results of simulation are given comparing the proposed method with earlier algorithms.
Tunable mid‐infrared generation by difference frequency mixing of diode laser wavelengths in intersubband InGaAs/AlAs quantum wells

We demonstrate difference frequency generation (DFG) of 8.66–11.34 μm wavelength light in intersubband InGaAs/AlAs quantum wells by mixing of 1.92 μm±25 nm and 2.39 μm±39 nm. The peak DFG second order nonlinear susceptibility χ(2) is measured to be 12±1 nm/V, more than 65 times that of GaAs, at a difference frequency output wavelength of 9.50 μm. The intersubband absorption for the 1–2 and 1–3 transitions is measured to be 9.3 and 2.1 μm, respectively. Second harmonic generation (SHG) of 4.76, 5.12, and 5.36 μm light with a CO2 laser is observed with a peak SHG χ(2) of 52±3 nm/V. Good agreement of experiment with theory is found for both the linear and nonlinear optical properties. This demonstration of mid‐infrared DFG opens the possibility for monolithic diode laser pumps and compact waveguide frequency converters as tunable midinfrared sources.
The heating of dust in starburst galaxies: The contribution of the nonionizing radiation

The IUE UV and optical spectra and the far-infrared (FIR) IRAS flux densities of a sample of starburst and blue compact galaxies are used to investigate the relationship between dust obscuration and dust emission. The amount of dust obscuration at UV wavelengths correlates with the FIR-to-blue ratio; and an analysis of the correlation indicates that not only the ionizing but also the nonionizing radiation contribute to the FIR emission. The amount of UV and optical energy lost to dust obscuration accounts for most of the cool dust FIUR emission and for about 70% of the warm dust FIR emission. The remaining 30% of the warm dust FIR flux is probably due to dust emission from regions of star formation which are embedded in opaque giant molecular clouds and do not contribute to the integrated UV and optical spectrum. The use of the FIR emission as an indicator of high-mass star formation rate in star-forming galaxies can be problematic, since the contribution to the FIR flux from cool dust emission heated by relatively old stars is nonnegligible.
Millimeter-Wave Precipitation Retrievals and Observed-versus-Simulated Radiance Distributions: Sensitivity to Assumptions

Abstract Brightness temperature histograms observed at 50–191 GHz by the Advanced Microwave Sounding Unit (AMSU) on operational NOAA satellites are shown to be consistent with predictions made using a mesoscale NWP model [the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5)] and a radiative transfer model [TBSCAT/F(λ)] for a global set of 122 storms coincident with the AMSU observations. Observable discrepancies between the observed and modeled histograms occurred when 1) snow and graupel mixing ratios were increased more than 15% and 25%, respectively, or their altitudes increased more than ∼25 mb; 2) the density, F(λ), of equivalent Mie-scattering ice spheres increased more than 0.03 g cm−3; and 3) the two-stream ice scattering increased more than ∼1%. Using the same MM5/TBSCAT/F(λ) model, neural networks were developed to retrieve the following from AMSU and geostationary microwave satellites: hydrometeor water paths, 15-min average surface-p.
A Sequential and Iterative Testing Procedure to Identify the Nature of a Time Series Generating Process

Abstract An inferential approach is proposed to identify the nature of the generating process corresponding to a real time series. This new sequential and iterative testing procedure goes beyond the Box and Jenkins methodology for the identification, estimation, and validation of linear data generating processes by investigating the probabilistic structure of non-Gaussian estimated residuals {ϵ t } for the possible presence of nonlinear serial dependence. The testing procedure aims at indicating the right type of dependence present in a series by means of specific inferential tests on the moments of the generating structure probability distribution. The test statistics adopted are very popular and powerful and encompass a wide range of stochastic nonlinearity alternatives. The U.S. Industrial Production Index series is used to illustrate the iterative testing procedure proposed.
X-ray substructure in A1656 and A2256

We report the confirmation of X-ray substructure in two rich clusters of galaxies, A1656 (Coma) and A2256. Using data from the Einstein Observatory imaging proportional counter, we present a technique of fitting the cluster profile and searching for contributions to the X-ray emission from small regions within the cluster. Using this method we find substructure in both A1656 and A2256 while simultaneously fitting the cluster profile. We obtain the ellipticity and position angle of both clusters as a function of radius and find that both have ellipticity and position angles which vary with radius. We interpret the existence of substructure along with the variable ellipticity and position angle as evidence for a recent merger in both of these clusters.
Design and analysis of interior-magnet outer-rotor concentric magnetic gears

In this paper, a new topology of concentric magnetic gears is proposed and implemented. The key of the new topology is to bury permanent magnets (PMs) of the outer rotor into the iron core in a new way so that the mechanical integrity can be improved, and the PM material can be saved while the torque density is maintained. The proposed gear is designed with the speed reduction ratio of 7.33 and optimized by using the three-dimensional finite element method (3D-FEM). The key of the 3D-FEM is to employ scalar magnetic potential to reduce the required memory and time for data manipulation and computation. After prototyping, the measured maximum static torque well agrees with the calculated one, hence verifying the proposed design and analysis.
Gamma-radiation imaging system based on the Compton effect

A novel gamma-ray camera is proposed that is based on the Compton effect. The basis of the device is a segmented semiconductor detector which is able to locate successive interaction points in multicollision trajectories and the associated energy losses. In this way, conic section can be computed on an image plane for each emission from a point source in the object. An overall image can be constructed by summation of the individual ellipses. The effect of measurement errors is investigated theoretically and by simulation, and leads to favourable estimates for the resolution and sensitivity of the camera. The question of image processing to improve performance is briefly discussed.
A numerical study of damage detection of underwater pipeline using vibration-based method

This paper presents a numerical investigation of the feasibility of condition monitoring of untrenched pipelines at seabed through ambient vibration measurements. A finite element (FE) model is developed to calculate the dynamic responses of pipelines to ambient wave forces. The model takes into consideration the interaction between the ocean waves, submarine pipeline, and seabed. The fluid around the pipeline is simulated using the acoustic fluid elements, while soil is simulated by springs and dashpots. The ambient hydrodynamic force in the marine environment is simulated based on the Joint North Sea Wave Observation Project (JONSWAP) spectrum. The transfer function from the wave surface elevation to the wave force is used to get the wave force spectrum. The dynamic responses of the pipe structure with different assumed damage conditions to the ambient wave forces are calculated. The calculated dynamic responses are assumed as measured ambient vibration data in condition monitoring to extract the pipeline vibration properties, which in turn are used in the FE model updating calculation to identify the pipeline conditions. Different noise levels are introduced into the calculated dynamic responses to simulate uncertainties that may arise from measurement and ambient hydrodynamic environment. The effect of noise levels on the extraction of pipeline vibration properties, and on the identification of the pipeline conditions is investigated.
Combined application of optical methods to increase the information content of optical coherent tomography in diagnostics of neoplastic processes

A combined application of optical methods [optical coherent tomography (OCT), cross-polarisation optical coherent tomography, and fluorescence spectroscopy] is proposed for obtaining information on morphological and biochemical changes occurring in tissues in norm and pathology. It is shown that neoplastic and scar changes in esophagus can be distinguished using a combination of polarisation and standard OCT due to the difference between the depolarising properties of the tissues caused by the structural properties of collagenic fibres in stroma. It is shown that OCT combined with fluorescence spectroscopy with the use of 5-aminolevulinic acid is promising for determining the boundaries of carcinoma of the uterine cervix and vulva. It is found that the tumour boundary detected by optical methods coincides with the morphological boundary and extends beyond colposcopically determined boundary by about 2 mm.
A NUMERICAL STUDY ON THERMAL FRACTURE OF PRECRACKED CERAMIC COATINGSIN HIGH-HEAT-FLUX ENVIRONMENT

The thermomechanical fracture and interface delamination of thermal barrier coatings (TBCs) in a high-heat-flux environment is the result of large surface temperature and thermal gradient across the coating thickness and the resulting viscoplastic deformations induced in the ceramic material. The maximum coating surface temperature has been used as the key loading parameter in previous studies. The current study explores the effects of several other thermal loading parameters on thermomechanical response and fracture behavior of TBCs with or without preexisting surface cracks. Results show that for a constant maximum surface temperature, the thermal fracture of the coating is increased by (i) an increased temperature difference across the coating, (ii) longer heating duration, and (iii) more aggressive coating surface cooling after heating. These results provide insights into TBC thermal fracture mechanisms and can potentially improve the design of the morphology of preexisting cracks in the coating to reduce fatal interface fracture.
Annular aperture detection scheme in radially polarized coherent anti-Stokes Raman scattering (RP-CARS) microscopy for contrast improvement

We report on a unique annular aperture detection scheme in radially polarized coherent anti-Stokes Raman scattering (RP-CARS) microscopy to effectively remove the solvent background for high contrast vibrational imaging. Our finite-difference time-domain (FDTD) calculations show that the far-field RP-CARS radiation from the scatterer with size comparable to the excitation wavelength is stronger than that from the solvent at large cone angles (around 45° to 150°). The annular detection provides about one order higher contrast for both forward and backward detected RP-CARS microscopy.
The interaction of Crab-like supernova remnants with their surroundings.

The interaction of a bubble of relativistic fluid created by pulsar energy input with an ambient meium is studied by means of self-similar solutions. Three possible ambient media are considered: a stationary, uniform medium; a medium created by a slow, steady presupernova wind; and a uniformly expanding medium created by a supernova explosion. The three situations lead to shells of shocked gas with different thicknesses and internal structures. The third case leads to a cooler shell than the other two. The models are applied to the Crab nebula. Current observations do not distinguish betwen the various models, but X-ray, radio, and ooptical observations are proposed which will be helpful in resolving this problem. The solution will indicate whether SN 1054 was an anomalously low-energy event.
High spectral resolution observations and kinematic modeling of the 1667 MHz hyperfine transition of OH in Comets Halley (1982i), Giacobini-Zinner (1984e), Hartley-Good (1985l), Thiele (1985m), and Wilson (1986l)

High-sensitivity, high spectral resolution 18 cm observations of Comets Giacobini-Zinner, Halley, Hartley-Good, Thiele, and Wilson are used here to probe the kinematics of the coma gas of these comets. The day/night outgassing ratio for all these comets is 1.39 (0.13 or - 0.12), independent of gas productivity and heliocentric distance. It is found that the gas productivity of a comet plays a critical role in determining the coma kinematics for bright comets near the sun.
Effect of Turbulence on the Aerodynamic Stability of Long Span Bridges

The study deals with the problem of turbulence effect on the instability of a long span suspended bridge. Wind tunnel test of three representative section models have been carried out in four type of passive grid turbulence flow to clarify the effect of turbulence intensity and turbulence scales. It was found that the turbulence has little effect on the derivatives of those streamlined deck sections, while it exhibits significant stabilizing effect on the bluff rectangular section prism. The loss of spanwise correlation may not be the main reasons induce the change of flutter stability in turbulence.
Improvement of Laminar Lifted Flame Stability Excited by High-Frequency Acoustic Oscillation

A high-frequency (20kHz) standing wave was applied to the unburned mixture upstream of a methane-air lifted jet flame using a bolt-clamped Langevin transducer (BLT) to improve stability. The flow field near the flame was visualized using acetone planar-laser-induced fluorescence (PLIF). The standing wave decreased the lifted flame height and increased the blow-off limit. The upstream flow field of the center jet then bent. This phenomenon appeared when there was a density difference between the center jet and the surrounding secondary flow. When the density of the center jet was less than that of the co-flow, the center jet was redirected to the pressure anti-node side. Conversely, when the density of the center jet was greater than that of the co-flow, the center jet was redirected to the pressure node side. This redirection tended to stabilize the laminar lifted flame.