Miracle-dz/UniFAR-FTUs huggingface dataset:
Optimal cutpoints for random observations

For the discretisation of a continuous random variable into different categories the choice of cutpoints is essential. A popular application is the contingent valuation method. In a parametric approach, the choice of cutpoints directly effects the quality of the estimates. Therefore, optimal cutpoints are desirable in order to estimate the parameters most accurately. We consider an arbitrary number of cutpoints and determine optimal cutpoints for the exponential and Gumbel distribution and prove that the c-optimal cutpoints for the location parameter of the logistic distribution have corresponding equal category probabilities. Furthermore, we show that in the limiting case for infinitely many cutpoints there is no loss of information.
Synergistic Antioxidant Activity and Optimal Microwave-Assisted Extraction Condition of Caesalpinia sappan L., Hibiscus sabdariffa L., and Clitoria ternatea L. Combinations

The aims of this work were to evaluate the synergistic antioxidant activity and optimize microwave-assisted extraction of Caesalpinia sappan L. , Hibiscus sabdariffa L. , and Clitoria ternatea L. combinations. The simplex lattice design was applied to evaluate the synergistic antioxidant activity. The mass ratios of the 3 plants that exhibited synergistic antioxidant activity were further used to investigate the optimal condition of microwave-assisted extraction by Box-Behnken design. Results showed that the synergistic antioxidant activity among the 3 plants: Which was determined by the combination index, was observed at various mass ratios, especially at the equal mass ratio. The optimal microwave-assisted extraction condition providing the best antioxidant activity of the plant extract was microwave power of 300 W for 30 s and 3 cycles. This condition gave the extraction yield of 31.03 ± 0.26 %, total phenolic content of 72.03 ± 3.83 mg GAE/g extract, total flavonoid content of 15.18 ± 0.42 mg CE/g extract, half-maximal inhibitory concentration (IC50) from DPPH assay of 178.16 ± 15.54 µg/mL and IC50 from FRAP assay of 75.26 ± 4.44 µg/mL. The optimal extract showed no toxicity on HepG2 cells although the tested concentration was up to 1 mg/mL with an IC50 value of 5.45 mg/mL. So, a mixture of the 3 colored plants could be used as a supplementary antioxidant product with a safety profile. HIGHLIGHTS Synergistic antioxidant activity was observed among three colored plants The optimal MAE condition was microwave power of 300 W for 30 s and three cycles The optimal extract did not toxic although the tested concentration was up to 1 mg/mL The IC50 of extract on cell viability was 5.45 mg/mL GRAPHICAL ABSTRACT
Phytochemistry and Antihyperglycemic Potential of Cistus salviifolius L., Cistaceae

Cistus salviifolius has been previously reported as a traditional remedy for hyperglycemia. However, the plant has been scarcely investigated from scientific point of view. Thus, the aim was to examine the chemical composition and to evaluate its antioxidant and antihyperglycemic potential in vitro. Aqueous and ethanolic extracts were evaluated for total phenolic, tannin, and flavonoid content using spectrophotometric methods. Detailed chemical characterization was performed by high-performance liquid chromatography (HPLC-DAD). The volatile organic compounds (VOCs) profile was assessed by gas chromatography technique. The potential in diabetes treatment was evaluated through tests of free radicals neutralization, inhibition of lipid peroxidation process, and test of ferric ion reduction; activity in tests of inhibition of α-amylase, α-glucosidase and dipeptidyl peptidase-4 was also evaluated. High content of phenolics (majority being tannins) was detected; detailed HPLC analysis revealed high content of gallic acid, followed by rutin, chlorogenic and caffeic acids. The VOCs analysis determined sesquiterpene hydrocarbons and oxygenated sesquiterpenes as the main groups of compounds. The assays classified extracts as potent neutralizers of 2,2-diphenyl-1-picrylhydrazil and nitroso radicals formation and potent inhibitors of α-amylase and α-glucosidase. In conclusion, Cistus salviifolius represents a rich source of phenolics and essential oil with sesquiterpenes. The established results suggested its promising antioxidant and antihyperglycemic activities.
A review of the application of machine learning technologies in vehicle navigation and positioning

In recent years, the accuracy requirement of vehicle navigation and positioning is higher and higher. Since some obvious disadvantages emerge in the integration of various traditional technologies, many studies have begun to apply machine learning to vehicle navigation and positioning, which utilize the powerful self-learning ability of machine learning algorithms. The main advantages of machine learning methods include solving the problem of narrow application scope of traditional information fusion algorithms. Solve the problems of low navigation and positioning accuracy and poor anti-interference ability. In this paper, the applications of machine learning related algorithms in vehicle navigation and localization are overviewed in detail, including support vector machines, neural networks and random forests. Meanwhile, the application research status of machine learning technology in vehicle navigation and positioning is summarized, and the future research directions are prospected.
WFCAM, Spitzer/IRAC and SCUBA observations of the massive star-forming region DR21/W75 -II. Stellar content and star formation

Wide field near-infrared observations and Spitzer Space Telescope IRAC observations of the DR21/W75 star formation regions are presented. The photometric data are used to analyse the extinction, stellar content and clustering in the entire region by using standard methods. A young stellar population is identified all over the observed field, which is found to be distributed in embedded clusters that are surrounded by a distributed halo population extending over a larger projected area. The Spitzer/IRAC data are used to compute a spectral index value, �, for each YSO in the field. We use these data to separate pure photospheres from disk excess sources. We find a small �
A Wide Dispersion in Star Formation Rate and Dynamical Mass of 108 Solar Mass Black Hole Host Galaxies at Redshift 6

Atacama Large Millimeter Array [C ii] line and continuum observations of five redshift quasars are presented. This sample was selected to probe quasars with lower black hole mass than most previous studies. We find a wide dispersion in properties with CFHQS J0216–0455, a low-luminosity quasar with absolute magnitude , remaining undetected implying a limit on the star formation rate in the host galaxy of , whereas other host galaxies have star formation rates up to hundreds of solar masses per year. Two other quasars have particularly interesting properties. VIMOS2911 is one of the least luminous quasars known with , yet its host galaxy is experiencing a very powerful starburst. PSO J167–13 has a broad and luminous [C ii] line and a neighboring galaxy a projected distance of 5 kpc away that is also detected in the [C ii] line and continuum. Combining with similar observations from the literature, we study the ratio of the [C ii] line to the far-infrared luminosity, finding that this ratio increases at high redshift at a fixed far-infrared luminosity, likely due to lower dust content, lower metallicity and/or higher gas masses. We compile a sample of 21 high-redshift quasars with dynamical masses and investigate the relationship between black hole mass and dynamical mass. The new observations presented here reveal dynamical masses consistent with the relationship defined by local galaxies. However, the full sample shows a very wide scatter across the black hole mass–dynamical mass plane, whereas both the local relationship and simulations of high-redshift quasars show a much lower dispersion in dynamical mass.
Susceptibility of High-Manganese Steel to High-Temperature Cracking

Tests were carried out on two high-Mn steels: 27Mn-4Si-2Al-Nb with Nb microaddition and 24Mn-3Si-1.5Al-Nb-Ti with Nb and Ti microadditions. High-manganese austenitic steels, due to their good strength and plastic properties belong to the AHSS (Advanced High-Strength Steel) group and are used in the automotive industry. The main difficulties faced during the casting of the steel and hot working are hot cracks, which can appear in the surface of the ingot. Cracks on the edges of the sheet after hot rolling are the reason for cutting the edges of the sheet and increasing production costs and material losses. The main reason for the formation of hot cracks is the decrease in metal ductility in the high-temperature brittleness range (HTBR). The width of the HTBR depends on mechanical properties and microstructural factors, i.e., non-metallic inclusions or intermetallic phases at austenite grain boundaries. In this paper, a hot tensile test was performed. The research was performed on the GLEEBLE 3800 thermomechanical simulator. This test allows us to determine the width of the high-temperature brittleness range (HTBR), the Nil Strength Temperature (NST), the Nil Ductility Temperature (NDT), and the Ductility Recovery Temperature (DRT). Hot ductility was determined from the value of the reduction in area R(A). The obtained results make it possible to determine the temperature of the beginning of hot working from the tested high-Mn steels. Fractographic research enabled us to define mechanisms of hot cracking. It was found that hot cracks form as a result of disruptions in the liquid film on crystals’ boundaries.
Dynamical Analysis of the Circumprimary Planet in the Eccentric Binary System HD 59686

We present a detailed orbital and stability analysis of the HD 59686 binary-star planet system. HD 59686 is a single-lined, moderately close (aB = 13.6 au) eccentric (eB = 0.73) binary, where the primary is an evolved K giant with mass M = 1.9 M⊙ and the secondary is a star with a minimum mass of mB = 0.53 M⊙. Additionally, on the basis of precise radial velocity (RV) data, a Jovian planet with a minimum mass of mp = 7 MJup, orbiting the primary on a nearly circular S-type orbit with ep = 0.05 and ap = 1.09 au, has recently been announced. We investigate large sets of orbital fits consistent with HD 59686's RV data by applying bootstrap and systematic grid search techniques coupled with self-consistent dynamical fitting. We perform long-term dynamical integrations of these fits to constrain the permitted orbital configurations. We find that if the binary and the planet in this system have prograde and aligned coplanar orbits, there are narrow regions of stable orbital solutions locked in a secular apsidal alignment with the angle between the periapses, Δω, librating about 0°. We also test a large number of mutually inclined dynamical models in an attempt to constrain the three-dimensional orbital architecture. We find that for nearly coplanar and retrograde orbits with mutual inclination 145° ≲ Δi ≤ 180°, the system is fully stable for a large range of orbital solutions.
Optimal modal controller design by entire eigenstructure assignment

A computationally simple sequential algorithm for designing an optimal modal controller is presented. The approach is capable of systematically calculating a set of appropriate weighting matrices for the cost functional in the quadratic performance index, so that the resulting optimal control law would not only minimise the cost functional, but also place the eigenspectrum of the closed-loop system at some predefined locations.
X-ray emission from young stars in Taurus-Auriga-Perseus: Luminosity functions and the rotation - activity - age - relation

We report on a systematic search for X-ray emission from pre-main sequence and young main sequence stars in the Taurus-Auriga-Perseus region. Our stellar sample consists of all T Tauri stars from the Taurus-Auriga region, and all late-type stars from the Pleiades and Hyades clusters which have been observed by the ROSAT PSPC in pointed observations. We present the X-ray parameters for all observed stars in tables. Next to the basic results of the data analysis (such as count rates, exposure time, and o-axis angle) we give X-ray luminosities and hardness ratios for all detected stars. Upper limits are given for non-detections. Detection rates for dierent spectral types are compiled. We use these results to study the connection between coronal X-ray activity and stellar parameters for dierent subgroups of our sample. In particular we compile X-ray luminosity functions (XLF), and discuss the relations between X-ray emission and spectral type, age, and rotation, which have been disputed extensively in the past. Here, we study these questions with the largest sample so far. The XLF for classical and weak-line T Tauri stars are dierent, with weak-lines being the stronger X-ray emitters. Proceeding towards the main-sequence (Pleiades, Hyades) the X-ray luminosity declines for all spectral types examined (G, K, and M stars). Within an age group Lx decreases towards later spectral types, while Lx=Lbol remains constant or even increases, reflecting the opposed influence of stellar radius, i.e. emitting area, and convection zone depth. For a given spectral type the fastest rotators show the highest X-ray luminosity. Rotation rate and X-ray emission are clearly correlated for all groups of stars with power law indices for log (Lx=Lbol )v ersus logProt of 0: 7t o 1:5. The study of XLF for binary stars shows that the known unresolved secondaries likely contribute a signicant amount to the X-ray emission.
Turbulent generation of magnetic fields in extended extragalactic radio sources

The need for in situ generation of magnetic energy in extended radio sources is shown to be present in all models. The question of whether such energy can be supplied by fully developed hydrodynamic turbulence is investigated through use of the nonlinear time-dependent equations of three-dimensional MHD turbulence. It is found that seed fields of 10/sup -9/ gauss can be amplified to equipartition values in approx.10/sup 8/ yr, but with a relatively low efficiency of approx.5%. The total energy requirements are consistent with estimates derived from particle reacceleration mechanisms. The production of ordered magnetic fields on very large scales is quite inefficient unless the kinetic energy input is accompanied by helical flow in all scales. Dynamical interactions with an external medium are considered to be a more likely source of large-scale field structure.
Metal surface energy: Persistent cancellation of short-range correlation effects beyond the random phase approximation

The role that nonlocal short-range correlation plays at metal surfaces is investigated by analyzing the correlation surface-energy into contributions from dynamical density fluctuations of various two-dimensional wave vectors. Although short-range correlation is known to yield considerable correction to the ground-state energy of both uniform and nonuniform systems, short-range correlation effects on intermediate and short-wavelength contributions to the surface formation energy are found to compensate one another. As a result, our calculated surface energies, which are based on a nonlocal exchange-correlation kernel that provides accurate total energies of a uniform electron gas, are found to be very close to those obtained in the random-phase approximation, and support the conclusion that the error introduced by the local-density approximation is small.
A link between ECM plasticity and synaptic morphological evolution

We made a link between Extra Cellular Matrix (ECM) plasticity and the morphologi cal changes in synapses after synaptic excitation. A recent study by Zhang et al \cite{zhang} showed tha t transmembrane voltage causes movement of the cell membrane. Here we will study the relation between th e mechanical properties of collagen which is the major component of the ECM and synaptic morphological c hanges in relation with the theory of DO Hebb \cite{hebb}
Effects of the sound speed of quintessence on the microwave background and large scale structure

One of the greatest challenges in cosmology today is to identify the nature of the dark energy component that comprises most of the energy density of the universe and that is causing the expansion of the universe to accelerate. [1] Two candidates are a cosmological constant (or vacuum density) and quintessence,[2] a dynamical energy component with negative pressure. Distinguishing the two is important for cosmology in order to refine our knowledge of the composition of the universe and to trace more accurately its evolution. It is even more important for fundamental physics since it informs us how we must modify unified theories to incorporate dark energy.
A k – ε turbulence closure model of an isothermal dry granular dense matter

The turbulent ﬂow characteristics of an isothermal dry granular dense matter with incompressible grains are investigated by the proposed ﬁrst-order k – ε turbulence closure model. Reynolds-ﬁlter process is applied to obtain the balance equations of the mean ﬁelds with two kinematic equations describing the time evolutions of the turbulent kinetic energy and dissipation. The ﬁrst and second laws of thermodynamics are used to derive the equilibrium closure relations satisfying turbulence realizability conditions, with the dynamic responses postulated by a quasi-linear theory. The established closure model is applied to analyses of a gravity-driven stationary ﬂow down an inclined moving plane. While the mean velocity decreases monotonically from its value on the moving plane toward the free surface, the mean porosity increases exponentially; the turbulent kinetic energy and dissipation evolve, respectively, from their minimum and maximum values on the plane toward their maximum and minimum values on the free surface. The evaluated mean velocity and porosity correspond to the experimental outcomes, while the turbulent dissipation distribution demonstrates a similarity to that of Newtonian ﬂuids in turbulent shear ﬂows. When compared to the zero-order model, the turbulent eddy evolution tends to enhance the transfer of the turbulent kinetic energy and plane shearing across the ﬂow layer, resulting in more intensive turbulent ﬂuctuation in the upper part of the ﬂow. Solid boundary as energy source and sink of the turbulent kinetic energy becomes more apparent in the established ﬁrst-order model. dissipation assumes a ﬁnite value on the free surface, which, when compared with the zero-order model, corresponds better to the observations. It is suggested that the zero-order model is sufﬁcient to account for the inﬂuence of turbulent ﬂuctuation in turbulent creeping ﬂows. For dense ﬂows, the ﬁrst-order model is more appropriate to account for the inﬂuence induced by turbulent eddy evolution, with solid boundaries apparently as energy source and sink of the turbulent kinetic energies of the solid grains.
Performance of the ATLAS Transition Radiation Tracker in Run 1 of the LHC: tracker properties

The tracking performance parameters of the ATLAS Transition Radiation Tracker (TRT) as part of the ATLAS inner detector are described in this paper for di ﬀ erent data-taking conditions in proton–proton, proton–lead and lead–lead collisions at the Large Hadron Collider (LHC). The performance is studied using data collected during the ﬁrst period of LHC operation (Run 1) and is compared with Monte Carlo simulations. The performance of the TRT, operating with two di ﬀ erent gas mixtures (xenon-based and argon-based) and its dependence on the TRT occupancy is presented. These studies show that the tracking performance of the TRT is similar for the two gas mixtures and that a signiﬁcant contribution to the particle momentum resolution is made by the TRT up to high particle densities.
Three-dimensional wave evolution on electrified falling films

We consider the full three-dimensional dynamics of a thin falling liquid film on a flat plate inclined at some non-zero angle to the horizontal. In addition to gravitational effects, the flow is driven by an electric field which is normal to the substrate far from the flow. This extends the work of Tseluiko & Papageorgiou (J. Fluid Mech., vol. 556, 2006b, pp. 361–386) by including transverse dynamics. We study both the cases of overlying and hanging films, where the liquid lies above or below the substrate, respectively. Starting with the Navier–Stokes equations coupled with electrostatics, a fully nonlinear two-dimensional Benney equation for the interfacial dynamics is derived, valid for waves that are long compared to the film thickness. The weakly nonlinear evolution is governed by a Kuramoto–Sivashinsky equation with a non-local term due to the electric field effect. The electric field term is linearly destabilising and produces growth rates proportional to $|\unicode[STIX]{x1D743}|^{3}$ , where $\unicode[STIX]{x1D743}$ is the wavenumber vector of the perturbations. It is found that transverse gravitational instabilities are always present for hanging films, and this leads to unboundedness of nonlinear solutions even in the absence of electric fields – this is due to the anisotropy of the nonlinearity. For overlying films and a restriction on the strength of the electric field, the equation is well-posed in the sense that it possesses bounded solutions. This two-dimensional equation is studied numerically for the case of periodic boundary conditions in order to assess the effects of inertia, electric field strength and the size of the periodic domain. Rich dynamical behaviours are observed and reported. For subcritical Reynolds number flows, a sufficiently strong electric field can promote non-trivial dynamics for some choices of domain size, leading to fully two-dimensional evolutions of the interface. We also observe two-dimensional spatiotemporal chaos on sufficiently large domains. For supercritical flows, such two-dimensional chaotic dynamics emerges in the absence of a field, and its presence enhances the amplitude of the fluctuations and broadens their spectrum.
Macro- and micro-structure of trust networks

A challenging problem in the social sciences is the characterization of the formation of ``social capital''. It is believed that societies with more social capital are more democratic and economically developed than societies with little social capital. However, social capital is a concept hard to quantify and measure in a ``real-word'' context. Here, we take advantage of an existing "web of trust'' between users of the "Pretty-Good-Privacy" (PGP) encryption algorithm, which is used in digital communication to ``sign'' documents so that the recipient knows for sure who the author is. Our analysis reveals the coexistence in the web of trust of a macro scale-free structure with micro strongly-connected cells in a complex network. We also show that when this network is intentionally attacked the scale-free structure rapidly disintegrates and that the resulting network is partitioned into a large number of small strongly-connected cells that are resilient to the intentional attack.
Non-perturbative aspects of (supersymmetric) gauge theories

At an elementary level, we present some non-perturbative aspects of non-abelian gauge theories in four dimensional space-time. Some rigorous results have been obtained in the framework of supersymmetric theories, and a very rich physics related to the strong-coupling dynamics of gauge fields has been discovered. Some of the new phenomena which appeared may play a significant role in future phenomenological models. However, quantitative computations in non-supersymmetric theories, like quantum chromodynamics, is out of reach for the moment.