Miracle-dz/UniFAR-FTUs huggingface dataset:
High-Field Phase Diagram and Spin Structure of Volborthite Cu3V2O7(OH)2·2H2O

We report results of 51 V NMR experiments on a high-quality powder sample of volborthite Cu 3 V 2 O 7 (OH) 2 ·2H 2 O, a spin-1/2 Heisenberg antiferromagnet on a distorted kagome lattice. Following the previous experiments in magnetic fields B below 12 T, the NMR measurements have been extended to higher fields up to 31 T. In addition to the two already known ordered phases (phases I and II), we found a new high-field phase (phase III) above 25 T, at which a second magnetization step has been observed. The transition from the paramagnetic phase to the antiferromagnetic phase III occurs at 26 K, which is much higher than the transition temperatures from the paramagnetic to the lower field phases I ( B < 4.5 T) and II (4.5< B < 25 T). At low temperatures, two types of the V sites are observed with different relaxation rates and line shapes in phase III as well as in phase II. Our results indicate that both phases II and III exhibit a heterogeneous spin state consisting of two spatially alternating Cu spin sy.
Nonperturbative volume reduction of large-N QCD with adjoint fermions

We use nonperturbative lattice techniques to study the volume-reduced 'Eguchi-Kawai' version of four-dimensional large-N QCD with a single adjoint Dirac fermion. We explore the phase diagram of this single-site theory in the space of quark mass and gauge coupling using Wilson fermions for a number of colors in the range 8{<=}N{<=}15. Our evidence suggests that these values of N are large enough to determine the nature of the phase diagram for N{yields}{infinity}. We identify the region in the parameter space where the (Z{sub N}){sup 4} center symmetry is intact. According to previous theoretical work using the orbifolding paradigm, and assuming that translation invariance is not spontaneously broken in the infinite-volume theory, in this region volume reduction holds: the single-site and infinite-volume theories become equivalent when N{yields}{infinity}. We find strong evidence that this region includes both light and heavy quarks (with masses that are at the cutoff scale), and our results are consistent with this region extending toward the continuum limit. We also compare the action density and the eigenvalue density of the overlap Dirac operator in the fundamental representation with those obtained in large-N pure-gauge theory.
In vitro antifungal examination of ethanol plant extracts from Berberis vulgaris and Tamarix tetrandra towards Monilia laxa and Phytophthora capsici

Tests in in vitro conditions with ethanol extracts from the radix of Berberis vulgaris and the flower twig of Tamarix tetrandra prepared by the method of maceration were performed with two economically important plant pathogens such as Monilia laxa and Phytophthora capsici. The received results show that the extracts from the radix of the common barberry (Berberis vulgaris) are able to fully block the growth of mycelium of Monilia laxa at 0.5 % (m/v) concentration during the entire period of testing (14 days). However, the effectiveness of the tested plant extracts towards Phytophthora capsici was significantly lower and Tamarix tetrandra expressed better action.
The orbital elements and physical properties of the eclipsing binary BD+36 3317, a probable member of $\delta$ Lyr cluster

Context. The fact that eclipsing binaries belong to a stellar group is useful, because the former can be used to estimate distance and additional properties of the latter, and vice versa. Aims. Our goal is to analyse new spectroscopic observations of BD$+36^\circ3317$ along with the photometric observations from the literature and, for the first time, to derive all basic physical properties of this binary. We aim to find out whether the binary is indeed a member of the $\delta$ Lyr open cluster. Methods. The spectra were reduced using the IRAF program and the radial velocities were measured with the program SPEFO. The line spectra of both components were disentangled with the program KOREL and compared to a grid of synthetic spectra. The final combined radial-velocity and photometric solution was obtained with the program PHOEBE. Results. We obtained the following physical elements of BD$+36^\circ3317$: $M_1 = 2.24\pm0.07 M_{\odot}$, $M_2 = 1.52\pm0.03 M_{\odot}$, $R_1 = 1.76\pm0.01 R_{\odot}$, $R_2 = 1.46\pm0.01 R_{\odot}$, $log L_1 = 1.52\pm0.08 L_{\odot}$, $log L_2 = 0.81\pm0.07 L_{\odot}$. We derived the effective temperatures $T_{eff,1} = 10450 \pm 420$ K, $T_{eff,2} = 7623 \pm 328$ K. Both components are located close to ZAMS in the Hertzsprung-Russell (HR) diagram and their masses and radii are consistent with the predictions of stellar evolutionary models. Our results imply the average distance to the system d = $330\pm29$ pc. We re-investigated the membership of BD$+36^\circ3317$ in the $\delta$ Lyr cluster and confirmed it. The distance to BD$+36^\circ3317$, given above, therefore represents an accurate estimate of the true distance for $\delta$ Lyr cluster. Conclusions. The reality of the $\delta$ Lyr cluster and the cluster membership of BD$+36^\circ3317$ have been reinforced.
Time flow in graphene and its implications on the cutoff frequency of ballistic graphene devices

This manuscript deals with time flow in ballistic graphene devices. It is commonly believed that in the ballistic regime the traversal time of carriers in gated graphene at normal incidence is just the ratio of the length of the device and the Fermi velocity. However, we show that the traversal time is much slower if the influence of metallic contacts on graphene is considered. Even the transmission at normal incidence becomes smaller than 1, contradicting yet another common belief. These unexpected effects are due to the transformation of Schrodinger electrons in the metallic contact into Dirac electrons in graphene and vice versa. As a direct consequence of these transformations, the ultimate performance of gated ballistic devices are much lower than expected, in agreement with experimental results.
Could regulatory information disclosure impact the behaviour of corporate over-financialization? Evidence from Chinese comment letters

ABSTRACT Taking Chinese A-share listed firms from 2014 to 2018 as our samples, this paper investigates the impact of regulatory information disclosure on corporate over-financialisation behaviour from comment letters. The empirical results show that financialisation-related comment letters can effectively reduce the behaviour of corporate over-financialisation, and this positive governance effect is more pronounced in companies with strong market arbitrage motivation. Further tests show that the more intensity of the financialisation-related comment letters, the higher the governance effect of comment letters on over-financialisation. Specifically, the governance effect of inquiries mechanism is more significant when the financialisation-related comment letters have the questions of “over-financialisation’. From the specific influence mechanism, the governance effect of financialisation-related comment letters is achieved by potential violation cost and the pressure of market attention. Finally, the governance effect of financialisation-related comment letters on over-financialisation can spill over to non-comment-letter-receivers in the same industry or in the same corporation groups.
The effect of inhomogeneities on dark energy constraints

Constraints on models of the late time acceleration of the universe assume the cosmological principle of homogeneity and isotropy on large scales. However, small scale inhomogeneities can alter observational and dynamical relations, affecting the inferred cosmological parameters. For precision constraints on the properties of dark energy, it is important to assess the potential systematic effects arising from these inhomogeneities. In this study, we use the Type Ia supernova magnitude-redshift relation to constrain the inhomogeneities as described by the Dyer-Roeder distance relation and the effect they have on the dark energy equation of state (w), together with priors derived from the most recent results of the measurements of the power spectrum of the Cosmic Microwave Background and Baryon Acoustic Oscillations. We find that the parameter describing the inhomogeneities (η) is weakly correlated with w. The best fit values w = −0.933 ± 0.065 and η = 0.61 ± 0.37 are consistent with homogeneity at < 2 σ level. Assuming homogeneity (η =1), we find w = −0.961 ± 0.055, indicating only a small change in w. For a time-dependent dark energy equation of state, w0 = −0.951 ± 0.112 and wa = 0.059 ± 0.418, to be compared with w0 = −0.983 ± 0.127 and wa = 0.07 ± 0.432 in the homogeneous case, which is also a very small change. We do not obtain constraints on the fraction of dark matter in compact objects, fp, at the 95% C.L. with conservative corrections to the distance formalism. Future supernova surveys will improve the constraints on η, and hence, fp, by a factor of ∼10.
Channel Bi-Diagonalization for MIMO Communications

This letter proposes a multi-input multi-output (MIMO) transceiver design termed channel bi-diagonalization (CBD), whose precoder and equalizer bi-diagonalize the channel matrix. By representing the bidiagonal MIMO channel with a trellis diagram, we can apply the Viterbi algorithm for the maximum likelihood (ML) detection and decoding, or the BCJR algorithm for the maximum a posteriori (MAP) detection and decoding, which drastically simplifies the optimal MIMO communications. Simulation results verify the superior performance of the proposed CBD scheme.
Two-dimensional models of early-type fast rotating stars: new challenges in stellar physics

Two-dimensional models of rapidly rotating stars are already unavoidable for the interpretation of interferometric or asteroseismic data of this kind of stars. When combined with time evolution, they will allow the including of a more accurate physics for the computation of element transport and the determination of surface abundances. In addition, modeling the evolution of rotation will improve gyrochronology. Presently, two-dimensional ESTER models predict the structure and the large-scale flows (differential rotation and meridional circulation) of stars with mass larger than 1.7Msun at any rotation rate. Main sequence evolution can be mimicked by varying the hydrogen content of the convective core. Models have been successfully tested on half a dozen of nearby fast rotating stars observed with optical or infra-red interferometers. They are now the right tool to investigate the oscillation spectrum of early-type fast rotators.
A REVERBERATION LAG FOR THE HIGH-IONIZATION COMPONENT OF THE BROAD-LINE REGION IN THE NARROW-LINE SEYFERT 1 Mrk 335

We present the first results from a detailed analysis of photometric and spectrophotometric data on the narrow-line Seyfert 1 (NLS1) galaxy Mrk 335, collected over a 120 day span in the fall of 2010. From these data we measure the lag in the He ii λ4686 broad emission line relative to the optical continuum to be 2.7 ± 0.6 days and the lag in the Hβλ4861 broad emission line to be 13.9 ± 0.9 days. Combined with the line width, the He ii lag yields a black hole mass MBH = (2.6 ± 0.8) × 107 M☉. This measurement is consistent with measurements made using the Hβλ4861 line, suggesting that the He ii emission originates in the same structure as Hβ, but at a much smaller radius. This constitutes the first robust lag measurement for a high-ionization line in an NLS1 galaxy and supports a scenario in which the He ii emission originates from gas in virial motion rather than outflow.
A stacked analysis of brightest cluster galaxies observed with the Fermi Large Area Telescope

We present the results of a search for high-energy γ-ray emission from a large sample of galaxy clusters sharing the properties of three existing Fermi Large Area Telescope detections (in Perseus, Virgo and A3392), namely a powerful radio source within their brightest cluster galaxy (BCG). From a parent, X-ray flux-limited sample of 863 clusters, we select 114 systems with a core-dominated BCG radio flux above 50/75 mJy (in the National Radio Astronomy Observatory Very Large Array Sky Survey and the Sydney University Molonglo Sky Survey, respectively), stacking data from the first 45 months of the Fermi mission in three energy bands, to determine statistical limits on the γ-ray fluxes of the ensemble of candidate sources. For a >300 MeV selection, the distribution of detection significance across the sample is consistent with that across control samples for significances 4σ signals which are not associated with previously identified γ-ray emission. Modelling of the data in these fields results in the detection of four non-2FGL Fermi sources, though none of these appear to be unambiguously associated with the BCG candidate. Only one is sufficiently close to be a plausible counterpart (RXC J0132.6−0804) and the remaining three appear to be background active galactic nuclei. A search at energies >3 GeV hints at emission from the BCG in A2055, which hosts a BL Lac object. There is no evidence for a signal in the stacked data, and the upper limit derived on the γ-ray flux of an average radio-bright BCG in each band is at least an order of magnitude more constraining than that calculated for individual objects. F1 GeV/F1.4 GHz for an average BCG in the sample is <15, compared with ≈120 for NGC 1275 in Perseus, which might indicate a special case for those objects detected at high energies. The tentative suggestion that point-like beamed emission from member galaxies comprise the dominant bright γ-ray sources in clusters implies searches for evidence of dark matter annihilation or large-scale merger shock signatures, for example, need to account for a significant level of contamination from within each cluster that is both highly stochastic and varies significantly over time.
Rotation measure synthesis study and polarized properties of PSR J1745−2900 at 7 mm

We present results of interferometric polarization observations of the recently discovered magnetar J1745-2900 in the vicinity of the Galactic center. The observations were made with the Karl G. Jansky Very Large Array (VLA) on 21 February 2014 in the range 40-48 GHz. The full polarization mode and A configuration of the array were used. The average total and linearly polarized flux density of the pulsar amounts to 2.3$\pm$0.31 mJy/beam and 1.5$\pm$0.2 mJy/beam, respectively. Analysis shows a rotation measure (RM) of (-67$\pm$3)x10$^3$ rad/m$^2$, which is in a good agreement with previous measurements at longer wavelengths. These high frequency observations are sensitive to RM values of up to ~2x10$^7$ rad/m$^2$. However, application of the Faraday RM synthesis technique did not reveal other significant RM components in the pulsar emission. This supports an external nature of a single thin Faraday-rotating screen which should be located close to the Galactic center. The Faraday corrected intrinsic electric vector position angle is 16$\pm$9 deg East of North, and coincides with the position angle of the pulsar's transverse velocity. All measurements of the pulsar's RM value to date, including the one presented here, well agree within errors, which points towards a steady nature of the Faraday-rotating medium.
Refraction in planetary atmospheres: improved analytical expressions and comparison with a new ray-tracing algorithm

Atmospheric refraction affects to various degrees exoplanet transit, lunar eclipse, as well as stellar occultation observations. Exoplanet retrieval algorithms often use analytical expressions for the column abundance along a ray traversing the atmosphere as well as for the deflection of that ray, which are first order approximations valid for low densities in a spherically symmetric homogeneous isothermal atmosphere. We derive new analytical formulae for both of these quantities, which are valid for higher densities, and use them to refine and validate a new ray tracing algorithm which can be used for arbitrary atmospheric temperature-pressure profiles. We illustrate with simple isothermal atmospheric profiles the consequences of our model for different planets: temperate Earth-like and Jovian-like planets, as well as HD189733b, and GJ1214b. We find that, for both hot exoplanets, our treatment of refraction does not make much of a difference to pressures as high as 10 atmosphere, but that it is important to consider the variation of gravity with altitude for GJ1214b. However, we find that the temperate atmospheres have an apparent scale height significantly smaller than their actual density scale height at densities larger than 1 amagat, thus increasing the difficulty of detecting spectral features originating in these regions. These denser atmospheric regions form a refractive boundary layer where column abundances and ray deflection increases dramatically with decreasing impact parameter. This refractive boundary layer mimics a surface, and none of the techniques mentioned above can probe atmospheric regions denser than about 4 amagat on these temperate planets.
Assessing Open Access Friendliness of National Institutes of Technology (NITs) A Data Carpentry Approach

This research study aims to measure the Open Access (OA) friendliness of National Institutes of Technology (NITs) of India that are listed in the overall category of NIRF (National Institutional Ranking Framework), 2021 by taking into consideration four important OA parameters – i) OA publication share; ii) OA licensing scenario; iii) citation impact of OA publications; and iv) altmetric scores of OA publications. It deals with 64,485 publications of the selected 11 NITs during the period from 2012 to 2021 (10 years), citations received by these publications (5,42,638 citations), and altmetric attention scores of the documents (5,213 publications) during the period under study. A data carpentry tool, namely OpenRefine, and open access bibliographic/citation data sources such as Unpaywall, Dimensions, and Altmetric.com have been deployed to accomplish this large-scale study for ranking NITs by their Open Access Friendliness (OAF). The OAF indicator, as applied in this study, is a distributed weightage based 100-point scale built on top of the aforesaid OA parameters. The ranking framework shows that Sardar Vallabhbhai National Institute of Technology, Surat (est. in 1961) has achieved the top position with a score of 52.12 (out of 100), but in totality only 3 NITs (out of the selected 11 NITs) crossed the 50 per cent mark in the adapted OAF scale.
Superconductivity in sodalite-like yttrium hydride clathrates

Motivated by the discovery of near-room-temperature superconductivity in the sodalite-like clathrate hydride ${\mathrm{LaH}}_{10}$, we report ab initio calculations of the superconducting properties of two closely related hydrides ${\mathrm{YH}}_{6}$ and ${\mathrm{YH}}_{10}$ for which an even higher ${T}_{\mathrm{c}}$ has been predicted. Using fully anisotropic Migdal-Eliashberg theory with Coulomb corrections, we find almost isotropic superconducting gaps, resulting from a uniform distribution of the coupling over states of both Y and H sublattices. The Coulomb screening is rather weak, resulting in a Morel-Anderson pseudopotential ${\ensuremath{\mu}}^{*}=0.11$, at odds with claims of unusually large ${\ensuremath{\mu}}^{*}$ in lanthanum hydrides. The corresponding critical temperatures at 300 GPa exceed room temperature (${T}_{\mathrm{c}}=290$ and 310 K for ${\mathrm{YH}}_{6}$ and ${\mathrm{YH}}_{10}$), in agreement with a previous isotropic-gap calculation. We estimate anharmonic effects to be weak. The different response of these two compounds to external pressure along with a comparison to low-${T}_{\mathrm{c}}$ superconducting ${\mathrm{YH}}_{3}$ may inspire strategies to improve the superconducting properties of this class of hydrides.
A PURE DIRAC'S METHOD FOR HUSAIN–KUCHAR THEORY

A pure Dirac's canonical analysis, defined in the full phase space for the Husain–Kuchar (HK) model is discussed in detail. This approach allows us to determine the extended action, the extended Hamiltonian, the complete constraint algebra and the gauge transformations for all variables that occur in the action principle. The complete set of constraints defined on the full phase space allow us to calculate the Dirac algebra structure of the theory and a local weighted measure for the path integral quantization method. Finally, we discuss briefly the necessary mathematical structure to perform the canonical quantization program within the framework of the loop quantum gravity approach.
Voltage modulated electro-luminescence spectroscopy to understand negative capacitance and the role of sub-bandgap states in light emitting devices

Voltage modulated electroluminescence spectra and low frequency (≤100 kHz) impedance characteristics of red electroluminescent diodes under forward bias are investigated. Light emission under periodic voltage modulation tracks the onset of observed negative capacitance for each modulation frequency. Active participation of sub-bandgap defects including the shallower states in minority carrier recombination dynamics is sought to explain the results. The phenomenon of negative capacitance is understood as a necessary dielectric response to compensate any irreversible transient changes in the injected minority carrier reservoir due to radiative recombinations mediated by slowly responding sub-bandgap defects. Experimentally measured variations of the in-phase component of modulated electroluminescence spectra with forward bias levels and with modulation frequencies support the dynamic influence of these sub-bandgap states in the radiative recombination process. Predominant negative sign of the in-phase compo.
Superuniversal transport near a $(2 + 1)$-dimensional quantum critical point

We compute the zero-temperature conductivity in the two-dimensional quantum $\mathrm{O}(N)$ model using a nonperturbative functional renormalization-group approach. At the quantum critical point we find a universal conductivity $\sigma^*/\sigma_Q$ (with $\sigma_Q=q^2/h$ the quantum of conductance and $q$ the charge) in reasonable quantitative agreement with quantum Monte Carlo simulations and conformal bootstrap results. In the ordered phase the conductivity tensor is defined, when $N\geq 3$, by two independent elements, $\sigma_{\mathrm{A}}(\omega)$ and $\sigma_{\mathrm{B}}(\omega)$, respectively associated to $\mathrm{O}(N)$ rotations which do and do not change the direction of the order parameter. Whereas $\sigma_{\mathrm{A}}(\omega\to 0)$ corresponds to the response of a superfluid (or perfect inductance), the numerical solution of the flow equations shows that $\lim_{\omega\to 0}\sigma_{\mathrm{B}}(\omega)/\sigma_Q=\sigma_{\mathrm{B}}^*/\sigma_Q$ is a superuniversal (i.e. $N$-independent) constant. These numerical results, as well as the known exact value $\sigma_{\mathrm{B}}^*/\sigma_Q=\pi/8$ in the large-$N$ limit, allow us to conjecture that $\sigma_{\mathrm{B}}^*/\sigma_Q=\pi/8$ holds for all values of $N$, a result that can be understood as a consequence of gauge invariance and asymptotic freedom of the Goldstone bosons in the low-energy limit.