Miracle-dz/UniFAR-FTUs huggingface dataset:
Modeling radio scattering and scintillation observations of the inner solar wind using oblique Alfvén/ion cyclotron waves

[1] Radio scattering and scintillation observations of the near-Sun solar wind are shown to be dominated by effects associated with obliquely propagating Alfven/ion cyclotron waves. We base this on a modeling of structure functions from angular/spectral broadening observations and velocity measurements from interplanetary scintillation (IPS) observations. A simple damped-WKB model was found inadequate, as Landau damping erodes the spectrum faster than is consistent with the observed inner scale. Invoking a turbulent cascade can counteract this damping and push the spectral cutoff back out to the observed inner scale near the ion inertial scale. Adjusting the spectrum amplitude and cascade rate to match observations gives an estimate of the wave dissipation power associated with electron Landau damping and proton cyclotron damping. The implied power levels are substantial, being comparable with levels typically invoked in extended wave heating models. Both the shape and the amplitude of the observed structure functions can be explained by a composite spectrum made up of a power law component of passive or non-Alfvenic density fluctuations and a local flattening associated with the enhanced linear Alfven wave compressibility at small (ion cyclotron) scales. Since IPS is dominated by the enhanced small-scale density fluctuations, the scintillation velocity field should show a strong wave effect. Our modeling of IPS velocities does, in fact, show that the large parallel velocity spread and upward bias to the mean velocity observed near the Sun are a direct result of the density fluctuations associated with Alfven waves along an extended line of sight.
Biophotonic sensors on a silicon chip for Raman spectroscopy and optical coherence tomography

We review our recent results on integrating biomedical optical systems onto a silicon chip. Light collection by integrated waveguides has been investigated. Confocal light delivery and collection by a combination of two arrayed-waveguide gratings has been achieved. Using an arrayed-waveguide grating as an integrated spectrometer, Raman spectroscopy and spectral-domain optical coherence tomography have been demonstrated.
Invariance conditions on substructures of division rings

Cartan–Brauer–Hua Theorem is a well-known theorem which states that if R is a subdivision ring of a division ring D which is invariant under all elements of D or dRd−1 ⊆ R for all d ∈ D∖{0}, then either R = D or R is contained in the center of D. The invariance idea of this basic theorem is the main notion of this paper. We prove that if D is a division ring with involution ∗ and M is a subspace of D which is invariant under all symmetric elements of D, then either M is contained in the center of D or is a Lie ideal of D. Also, we show that if T is a self-invariant subfield of a non-commutative division ring D with a nontrivial automorphism, then T contains at least one non-central proper subfield of D.
An outsider's view of the Galaxy: photometric parameters, scale lengths, and absolute magnitudes of the spheroidal and disk components of our Galaxy.

A two-component model of the Galaxy consisting of (I) an R/sup 1/4/ spheroid of effective radius r/sup I//sub e/=2.67 kpc (for r/sub 0/=8.0 kpc) and peak brightness . mu. /sup I//sub B/(0) =15.11 mag arcsec/sup -2/, and (II) an exponential disk of effective radius r/sup II//sub e/=5.98 kpc and (assumed) peak brightness . mu. /sup II//sub B/(0) =21.65 (after Freeman) is shown to be consistent with the galactic disk brightness inferred from star counts and to give a good representation of new observations of the brightness distribution in the bulge along galactic meridian 0/sup degree/. An ellipsoidal model of the spheroid with a/sup I//sub e/=3.45 kpc and c/a=0.6 is also considered with little change in most results; averages from the two cases are adopted. For an outside observer the face-on total absolute magnitude of the Galaxy (with allowance for uniform internal extinction of total optical depth A/sub B/=0.4 mag) is M/sup 0//sub T/(B) =-20.08 or L/sub T/(B) =1.6 x 10/sup 10/L/sub sun/, of which half is emitted within the effective radius r/sub e/=5.1 kpc. The fraction K/sub I/=L/sup I//L/sub T/=0.34 +- 0.04 contributed by the spheroidal component is in close agreement with corresponding values for several Sbc (T=4) galaxies. The calculated standard face-on isophotalmore » diameter of the Galaxy at the . mu. /sub B/=25.0 level, D/sub 0/=23.0 kpc is in close agreement with three independent estimates (21.4--23.4) from statistical relations for spiral galaxies. The luminosity index . lambda. = (T+L)/10 of the Galaxy derived by three independent methods is . lambda. =0.71 +- 0.03, implying a luminosity class L=3 +- 1 (LC=II), if T=4 +- 0.5. The mean intrinsic color (corrected for extinction) of the spheroidal component derived from the observations is /sub I/=0.65 +- 0.05; that of the disk stellar population derived from local luminosity functions is /sub II/=0.40 (after Holmberg, transformed to B,V system). « less
Testing the Fit of a Parametric Function

Abstract General methods for testing the fit of a parametric function are proposed. The idea underlying each method is to “accept” the prescribed parametric model if and only if it is chosen by a model selection criterion. Several different selection criteria are considered, including one based on a modified version of the Akaike information criterion and others based on various score statistics. The tests have a connection with nonparametric smoothing because they use orthogonal series estimators to detect departures from a parametric model. An important aspect of the tests is that they can be applied in a wide variety of settings, including generalized linear models, spectral analysis, the goodness-of-fit problem, and longitudinal data analysis. Implementation using standard statistical software is straightforward. Asymptotic distribution theory for several test statistics is described, and the tests are shown to be consistent against essentially any alternative hypothesis. Simulations and a data exampl.
Shapes of worn stones

Often stones on beaches pounded by waves wear into quite smooth, regular shapes, sometimes apparently ellipsoidal and even spherical [8]. This paper begins with an idealization of this wearing process for materials isotropic with respect to wear, then develops an equation governing the idealized process, and goes on to show that a stone which is initially convex and centrally symmetric tends to assume a spherical shape as a consequence of the governing equation. This conclusion is predicated on the assumption that the mathematical conditions describing the wearing process are those of a well-posed problem.
Mechanism of the long-wave inertialess instability of a two-layer film flow

This paper provides an intuitive interpretation of the long-wave inertialess instability of a two-layer film flow. The underlying mechanism is elucidated by inspecting the longitudinal perturbation velocity associated with the surface and interfacial deflections. The velocity is expressed by the composition of three parts, related to the shear stress at the free surface, the continuity condition at the interface, and the pressure disturbance induced by gravity. The effect of each velocity component on the evolutions of the surface and the interface is examined in detail. Specifically, the growth of the free surface is caused by the continuity-induced first-order velocity disturbance associated with an additional phase shift between the surface and interfacial waves, while the growth of the interface is due to the pressure-driven flow. The proposed mechanism gives an alternatively reliable prediction of the wave velocity and growth rate.
On the size requirement for finite phased-array models

The question considered is how large an array model must be in order to capture approximately the characteristics of both the interior and the edge elements of a large multi-octave phased array. Arrays with tapered slot elements and with top-loaded dipoles are analyzed at element spacings as small as 0.1/spl lambda/ and it is concluded that at any frequency, a finite array model with this type of element should be at least 5/spl lambda//spl times/5/spl lambda/ in size. This suggests the generalization of the 10/spl times/10 element model often used as an engineering "rule of thumb" in the normal narrow-band case with 0.5/spl lambda/ element spacing. An array model with a 5:1 bandwidth thus needs about 25 times more elements than a narrow-band model. The array feed impedance is considered and it is found that the array active reflection coefficient in finite arrays but not in infinite arrays is dependent on the matching condition at the feed. The finite-difference time-domain (FDTD) technique is used to analyze arrays up to 49/spl times/49 elements, demonstrating that computer power now makes feasible the full wave solution for large phased arrays with complex geometry.
Seed Bubble Guided Heat Transfer in a Single Microchannel

We use the seed bubble concept for manipulating the evaporative heat transfer in a heated microchannel with smooth surfaces. Using this concept, separation of bubble nucleation and growth is obtained to simplify the heat transfer system. Not only is the temperature excursion at the boiling incipience eliminated, but also the heat transfer system displays well-ordered and repeated flow characteristics. The heat transfer rates and wall temperatures can be controlled through adjusting the seed bubble frequency. The method provides a thermal management solution for microsystems and a tool for the study of the intricate flow and heat transfer.
Synergetic Use of GPS Water Vapor and Meteosat Images for Synoptic Weather Forecasting

The use of integrated water vapor (IWV) measurements from a ground-based global positioning system (GPS) for nowcasting is described for a cold front that passed the Netherlands during 16 and 17 May 2000. Meteosat water vapor (WV) and infrared (IR) channel measurements are incorporated to analyze this weather situation. A cloud band with embedded cumulonimbus clouds (Cb) preceded the cold front. The GPS IWV showed a clear signal at the passing time of the embedded Cbs over the GPS sites. After the frontal passage a dry intrusion occurred. By comparing Meteosat WV observations collocated in time and space with GPS IWV observations, a rough reconstruction of the vertical water vapor distribution can be made. The case described here shows that, in addition to Meteosat WV/IR images, GPS IWV contained information for nowcasting of the probability of the occurrence of thunderstorms and heavy precipitation.
DC-Biased Piezoelectret Film Transducers for Airborne Ultrasound

Ultrasonic senders with DC-biased piezoelectret films were built and characterized. The generated sound pressure of the transducers is inversely proportional to the distance from the transducer and proportional to transducer size, AC-voltage, square of the frequency, and effective d33-coefficient of the films. With polypropylene films and DC-voltages of 1000 V, effective d33-coefficients of more than 750 pC/N are obtained. For an applied signal AC-voltage of 46 Vrms, a transducer area of 1.8 cm2, and a distance of 60 mm, sound pressures exceeding 10 Pa were measured in the frequency range above 100 kHz. With stacks of 2 and 3 piezoelectret film layers, effective d33-coefficients up to 1500 pC/N and sound pressures of about 20 and 40 Pa, respectively, could be obtained at frequencies between 60 and 120 kHz. This represents, for otherwise equal parameters, an increase by about a factor of four compared to previous piezoelectret transducers.
Clouds at Arctic Atmospheric Observatories. Part II: Thermodynamic Phase Characteristics

Abstract Cloud phase defines many cloud properties and determines the ways in which clouds interact with other aspects of the climate system. The occurrence fraction and characteristics of clouds distinguished by their phase are examined at three Arctic atmospheric observatories. Each observatory has the basic suite of instruments that are necessary to identify cloud phase, namely, cloud radar, depolarization lidar, microwave radiometer, and twice-daily radiosondes. At these observatories, ice clouds are more prevalent than mixed-phase clouds, which are more prevalent than liquid-only clouds. Cloud ice occurs 60%–70% of the time over a typical year, at heights up to 11 km. Liquid water occurs at temperatures above −40°C and is increasingly more likely as temperatures increase. Within the temperature range from −40° to −30°C, liquid water occurs in 3%–5% of the observed cloudiness. Liquid water is found higher in the atmosphere when accompanied by ice; there are few liquid-only clouds above 3 km, although .
Self-organization of decaying quasi-two-dimensional turbulence in stratified fluid in rectangular containers

Laboratory experiments on decaying quasi-two-dimensional turbulence have been performed in stratified fluid inside containers with length-to-width ratios $\delta$ up to 5. The Reynolds number $Re$ of the horizontal flow, based on the r.m.s. velocity of the initial flow field and the half-width $H$ of the container, was typically between 1000 and 3000. The turbulence was generated by towing an array of vertical cylinders through the container which was filled with a two-layer stratified fluid. By varying the grid configuration a different amount of angular momentum could be added to the initial flow. The evolution of the flow was visualized by two-dimensional particle tracking velocimetry. The observed decay has been investigated with the emphasis on the final states as function of $\delta$, $Re$ and the angular momentum initially added to the flow. In addition, numerical simulations were carried out for decaying two-dimensional turbulence on rectangular domains with $\delta\,{=}\,2$ and 3. In these runs zero net angular momentum was added to the initial flow field. The numerical study focused on the final states as a function of $\delta$ and $Re$. The numerically obtained final states appeared to agree with the experimental observations. Furthermore, they indicate a clear difference between the predictions of quasi-stationary final states from statistical-mechanical theories and the final states as found in the numerical simulations.
Multivariate generalization of t'- statistic based on the mean square successive difference

The usual t-statistic is not useful if the successive observations have some kind of linear trend. This generally arises in the drug testing experiment and it is clearly pointed out by Shah (1988). He suggests to use t'-statistic which is defined by for testing μ = 0 where , and y1. ,…,yk are independent observations from . We generalize this statistic to multivariate situation and define T'-statistic as where . The exact null distribution of T' and an approximate null distribution of T' are obtained. For p = 1, this approximate values are compared.
A Unified Gas-Kinetic Scheme for Continuum and Rarefied Flows III: Microflow Simulations

Due to the rapid advances in micro-electro-mechanical systems (MEMS), the study of microflows becomes increasingly important. Currently, the molecular-based simulation techniques are the most reliable methods for rarefied flow computation, even though these methods face statistical scattering problem in the low speed limit. With discretized particle velocity space, a unified gas-kinetic scheme (UGKS) for entire Knudsen number flow has been constructed recently for flow computation. Contrary to the particle-based direct simulation Monte Carlo (DSMC) method, the unified scheme is a partial differential equation-based modeling method, where the statistical noise is totally removed. But, the common point between the DSMC and UGKS is that both methods are constructed through direct modeling in the discretized space. Due to the multiscale modeling in the unified method, i.e., the update of both macroscopic flow variables and microscopic gas distribution function, the conventional constraint of time step being less than the particle collision time in many direct Boltzmann solvers is released here. The numerical tests show that the unified scheme is more efficient than the particle-based methods in the low speed rarefied flow computation. The main purpose of the current study is to validate the accuracy of the unified scheme in the capturing of non-equilibrium flow phenomena. In the continuum and free molecular limits, the gas distribution function used in the unified scheme for the flux evaluation at a cell interface goes to the corresponding Navier-Stokes and free molecular solutions. In the transition regime, the DSMC solution will be used for the validation of UGKS results. This study shows that the unified scheme is indeed a reliable and accurate flow solver for low speed non-equilibrium flows. It not only recovers the DSMC results whenever available, but also provides high resolution results in cases where the DSMC can hardly afford the computational cost. In thermal creep flow simulation, surprising solution, such as the gas flowing from hot to cold regions along the wall surface, is observed for the first time by the unified scheme, which is confirmed later through intensive DSMC computation.
Some New Results on Eigenvectors via Dimension, Diameter, and Ricci Curvature☆

Abstract We generalise for a general symmetric elliptic operator the different notions of dimension, diameter, and Ricci curvature, which coincide with the usual notions in the case of the Laplace–Beltrami operators on Riemannian manifolds. If λ 1 denotes the spectral gap, that is the first nonzero eigenvalue, we investigate in this paper the best lower bound on λ 1 one can obtain under an upper bound on the dimension, an upper bound on the diameter, and a lower bound of the Ricci curvature. Two cases are known: namely if the Ricci curvature is bounded below by a constant R >0, then λ 1 ⩾ nR /( n −1), and this estimate is sharp for the n -dimensional spheres (Lichnerowicz's bound). If the Ricci curvature is bounded below by zero, then Zhong–Yang's estimate asserts that λ 1 ⩾ π 2 d 2 , where d is an upper bound on the diameter. This estimate is sharp for the 1-dimensional torus. In the general case, many interesting estimates have been obtained. This paper provides a general optimal comparison result for λ 1 which unifies and sharpens Lichnerowicz and Zhong–Yang's estimates, together with other comparison results concerning the range of the associated eigenfunctions and their derivatives.
Modeling of thin insulating layers with dual 3-D magnetodynamic formulations

The treatment of thin insulating layers between conducting regions is studied in the frame of dual three-dimensional (3-D) magnetodynamic finite element formulations, using either the magnetic field or the magnetic vector potential as the main unknowns. The layers, of which the thickness is assumed to tend to zero, are represented by surface elements on which scalar potentials are defined and coupled with the main field of each formulation. At the discrete level, this coupling is rigorously done through a nodal and edge-elements coupling. Both passive and active conducting regions are considered, i.e., without or with applied voltage or current.
An S-Related DCV Generated by a Convex Function in a Jump Market

We consider an incomplete market with general jumps, in which the discounted price process S of a risky asset is a given bounded semimartingale. We continue our work on the S-related dynamic convex valuation (DCV) initiated in Xiong and Kohlmann [23] by considering here an S-related DCV whose dynamic penalty functional is generated by a convex function . So the penalty functional takes the following form where is the density process of an equivalent martingale measure (EMM) Q for S with respect to the fundamental EMM Q 0. For a given ξ ∈L ∞(ℱ T ), we prove that is the first component of the minimal bounded solution of a backward semimartingale equation (BSE) generated by a convex, possibly non-Lipschitz g. If this BSE has a bounded solution such that θ2 is also bounded and , we prove that , Q 0-a.s. , for all t ∈ [0, T]. Finally, we introduce the concept of a bounded -(super-)martingale and derive a decomposition for a -supermartingale.
Eukaryotic Clathrin Adapter Protein and Mediator of Cholesterol Homeostasis, PICALM, Affects Trafficking to the Chlamydial Inclusion

Abstract The obligate intracellular pathogen Chlamydia trachomatis has unique metabolic requirements as it proceeds through its biphasic developmental cycle from within the inclusion within the host cell. In our previous study, we identified a host protein, PICALM, which localizes to the chlamydial inclusion. PICALM functions in many host pathways including the recycling of receptors, specific SNARE proteins, and molecules like transferrin, and maintaining cholesterol homeostasis. Hence, we hypothesized that PICALM functions to maintain the cholesterol content and to moderate trafficking from the endosomal recycling pathway to the inclusion, which controls chlamydial access to this pathway. In uninfected cells, siRNA knockdown of PICALM resulted in increased cholesterol within the Golgi and transferrin receptor (TfR) positive vesicles (recycling endosomes). PICALM knockdown in cells infected with C. trachomatis resulted in increased levels of Golgi-derived lipid and protein, TfR, transferrin, and Rab11-FIP1 localized to inclusions and a decrease of Golgi fragmentation at and Rab11 trafficking to the inclusion. Interestingly, chlamydial infection alone also increases cholesterol in TfR and Rab11-associated vesicles, and PICALM knockdown reverses this effect. Our data suggest that PICALM functions to balance or limit chlamydial access to multiple subcellular trafficking pathways to maintain the health of the host cell during chlamydial infection.
Peripheral immune factors aiding clinical parameter for better early recurrence prediction of hepatocellular carcinoma after thermal ablation

Abstract Objectives Current predictors are largely unsatisfied for early recurrence (ER) of hepatocellular carcinoma (HCC) after thermal ablation. We aimed to explore the prognostic value of peripheral immune factors (PIFs) for better ER prediction of HCC after thermal ablation. Methods Patients who received peripheral blood mononuclear cells (PBMCs) tests before thermal ablation were included. Clinical parameters and 18 PIFs were selected to construct ModelClin, ModelPIFs and the hybrid ModelPIFs-Clin. Model performances were evaluated using area under the curve (AUC), and recurrence-free survival (RFS) were analyzed by Kaplan-Meier analysis and log-rank tests. Results 244 patients were included and were randomly divided in 3:1 ratio to discovery and validation cohorts. Clinical parameters including tumor size and AFP, and PIFs including neutrophils, platelets, CD3+CD16+CD56+ NKT and CD8+CD28- T lymphocytes were selected. The ModelPIFs-Clin showed increase in predictive performance compared with ModelClin, with the AUC improved from 0.664 (95%CI:0.588–0.740) to 0.801 (95%CI:0.734–0.867) in discovery cohort (p < 0.0001), and from 0.645 (95%CI:0.510–0.781) to 0.737(95%CI:0.608–0.865) in validation cohort (p = 0.1006). ModelPIFs-Clin enabled ER risk stratification of patients. Patients predicted in ModelPIFs-Clin high-risk subgroup had a poor RFS compared with those predicted as ModelPIFs-Clin low-risk subgroup, with the median RFS was 18.00 month versus 100.78 month in discovery cohort (p < 0.0001); and 24.00 month versus 60.35 month in validation cohort (p = 0.288). Patients in different risk subgroups exhibited distinct peripheral immune contexture. Conclusions Peripheral immune cells aiding clinical parameters boosted the prediction ability for ER of HCC after thermal ablation, which be helpful for pre-ablation ER risk stratification.