Miracle-dz/UniFAR-FTUs huggingface dataset:
$B$-sets and coloring problems

1. Definitions. Let F{Xa:a£:A} be a family of sets. A set B is called a 5-set for this family if Br\Xa5 0, all aE^4, and B^Xay all « G i . A family F need not have a B-set. Observe that if B is a . B-set for Ft then so is the complement of B. Consider a map covering 52, the two-dimensional sphere. We shall assume that it is regular, tha t is, each vertex is of degree three. Each region of the map is a topological cell. Two regions are adjacent if they share a t least one edge. A sequence of distinct regions J? i, i? 2, • • • » Rn, w è 3, is a cycle of length n if Ri is adjacent to JR*+I, l g i g w — 1 , and Rn is adjacent to R\. The cycle is odd or even according as n is odd or even.
A study of star formation in the disks of Sa galaxies

This paper compares the luminosity functions of the H II regions in several Sa galaxies with those of later-type galaxies. Broad UV measurements confirm expectations that the knots associated with the regions are very blue; the converse is also true. The H II region luminosity functions are very steep. The total H-alpha luminosities for the galaxies are computed and used to derive the current star-formation rates. It is found that, in contrast to the late-type galaxies, the current star-formation rates in Sa disks are less than one-tenth of the average rate over the last 15 Gyr. The formal depletion times of gas through star formation are longer than a Hubble time. If the star formation in late-type galaxies takes on the character of that currently seen in the Sas, star formation in such galaxies could continue for much longer than the usual estimate of 5 Gyr. 35 refs.
The Impact of the COVID-19 Pandemic on Mental Health and Quality of Life in COVID-19 Department Healthcare Workers in Central Greece

Background: The pandemic crisis created conditions of insecurity and threat and brought about changes in social contacts and everyday life. Frontline healthcare workers (HCW) were mostly affected. We aimed to evaluate the quality of life and negative emotions in COVID-19 HCW and searched for factors influencing the above. Methods: The present study was conducted among three different academic hospitals in central Greece (04/2020–03/2021). Demographics, attitude towards COVID-19, quality of life, depression, anxiety, stress (using the WHOQOL-BREF and DASS21 questionnaire) and the fear of COVID-19 were assessed. Factors affecting the reported quality of life were also assessed. Results: The study involved 170 HCW in COVID-19 dedicated departments. Moderate levels of quality of life (62.4%), satisfaction with social relations (42.4%), working environment (55.9%) and mental health (59.4%) were reported. Stress was present in 30.6% of HCW; 20.6% reported fear for COVID-19, depression (10.6%) and anxiety (8.2%). HCW in the tertiary hospital were more satisfied with social relations and working environment and had less anxiety. Personal Protective Equipment (PPE) availability affected the quality of life, satisfaction in the work environment and the presence of anxiety and stress. Feeling safe during work influenced social relations and fear of COVID-19 Conclusion: The HCW quality of life is affected in the pandemic. Feelings of safety during work related to the reported quality of life.
A Wideband Planar Dipole Antenna Array Fed by SICL for Millimeter Wave Applications

A wideband substrate integrated coaxial line (SICL)-fed planar dipole antenna array is investigated for millimeter wave applications. Different from the traditional dual-armed dipole antenna, a balanced symmetric structure is formed to improve the cross-polarization level by canceling the vertically polarized electric-field components. Meanwhile, three slots are etched on the dipole arms for two operating modes to broaden the operating bandwidth of the dipole element. By these methods, the dipole antenna achieves a cross-polarization level below −28 dB and an impedance bandwidth of more than 65%. To further improve the gain of the antenna, a $1\times 8$ dipole array is proposed. The measured results show that the proposed dipole array can achieve a wide −10 dB impedance bandwidth of more than 70.6% from 22.3 to 47 GHz, and cross-polarization levels below −20 dB. With the merits of wideband, low cross-polarization, low profile and easy integration, the proposed antenna array is valuable to millimeter wave communication.
Generic Automorphisms of Homogeneous Structures

Let G be a permutation group on the set Ω. Usually we take |Ω|=N o . We seek a notion of genericity for members of G. The idea is that a member of G should be generic if it is in some sense typical. We argue that the following is the correct definition. Suppose that G is endowed with a metric so that it becomes a complete metric space. It follows that the Baire category theorem holds, and we may use the notions of meagre and comeagre sets
Wide Binary Systems and the Nature of High-Velocity White Dwarfs

We present measured radial velocities and complete space motions for 116 white dwarf stars with M dwarf companions. Thirteen pairs have "halo-like" velocities. According to a recent study by Oppenheimer et al., all these high-velocity white dwarfs should be considered part of the dark matter heavy halo of the Galaxy, based on their kinematics. Based on the near-solar abundance levels of the M dwarf companions, we conclude that 12 of our 13 high-velocity white dwarfs are actually part of the high-velocity tail of the thick disk, rather than the dark matter halo of the Galaxy, in agreement with the results of a recent study of 514 M dwarfs performed by Reid, Sahu, & Hawley. We find only one potential stellar halo white dwarf (LP 164-52) in our sample. The M dwarf companion of LP 164-52 is a metal-poor, intermediate subdwarf with high-velocity UVW-space motions. In view of the similarity to our sample, we conclude that the majority of the dark matter halo white dwarfs identified by Oppenheimer et al. are most likely to be members of the thick disk, and hence their contribution to the dark matter content of the halo is very much overestimated. Our results suggest that the assignment of population membership solely on incomplete kinematical information is not definitive and that a more robust examination of suspected halo white dwarfs must be performed.
Exposure to Low Levels of Radiofrequency Electromagnetic Fields Emitted from Cell-phones as a Promising Treatment of Alzheimer’s Disease: A Scoping Review Study

Background: Alzheimer’s disease (AD) is one of the most significant public health concerns and tremendous economic challenges. Studies conducted over the past decades show that exposure to radiofrequency electromagnetic fields (RF-EMFs) may relieve AD symptoms. Objective: To determine if exposure to RF-EMFs emitted by cellphones affect the risk of AD. Material and Methods: In this review, all relevant published articles reporting an association of cell phone use with AD were studied. We systematically searched international datasets to identify relevant studies. Finally, 33 studies were included in the review. Our review discusses the effects of RF-EMFs on the amyloid β (Aβ), oxidative stress, apoptosis, reactive oxygen species (ROS), neuronal death, and astrocyte responses. Moreover, the role of exposure parameters, including the type of exposure, its duration, and specific absorption rate (SAR), are discussed. Results: Progressive factors of AD such as Aβ, myelin basic protein (MBP), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, and neurofilament light polypeptide (NFL) were decreased. While tau protein showed no change, factors affecting brain activity such as glial fibrillary acidic protein (GFAP), mitogen-activated protein kinases (MAPKs), cerebral blood flow (CBF), brain temperature, and neuronal activity were increased. Conclusion: Exposure to low levels of RF-EMFs can reduce the risk of AD by increasing MAPK and GFAP and decreasing MBP. Considering the role of apoptosis in AD and the effect of RF-EMF on the progression of the process, this review indicates the positive effect of these exposures.
Early Origins of Chronic Obstructive Pulmonary Disease: Prenatal and Early Life Risk Factors

The main risk factor for chronic obstructive pulmonary disease (COPD) is active smoking. However, a considerable amount of people with COPD never smoked, and increasing evidence suggests that adult lung disease can have its origins in prenatal and early life. This article reviews some of the factors that can potentially affect lung development and lung function trajectories throughout the lifespan from genetics and prematurity to respiratory tract infections and childhood asthma. Maternal smoking and air pollution exposure were also analyzed among the environmental factors. The adoption of preventive strategies to avoid these risk factors since the prenatal period may be crucial to prevent, delay the onset or modify the progression of COPD lung disease throughout life.
On Generalized Fractional Integration of Aleph ( ℵ ) -Function

In the present paper, we establish two theorems exhibiting images of the product of Aleph ( ℵ ) -function and Srivastava’s polynomials (J Math 14:1–6, 1972) in Saigo operators (Math Rep Kyushu Univ 11:135–143, 1978). Being of general and uniﬁed in nature, the results established here yield a large number of new and known images involving Riemann– Liouville and Erd’elyi–Kober fractional integral operators and several special functions as special cases. To illustrate, four corollaries have been recorded here.
Radio lobes and forbidden O III profile substructure in Seyfert galaxies

High spatial and spectral resolution observations are presented for 10 Seyfert galaxies in the H-beta-forbidden O III 5007 A spectral region. In most of the objects, there is evidence for forbidden O III profile substructure, which appears to be most conspicuous close to the location of a radio lobe. The relative intensities of forbidden O III component emission and ambient forbidden O III emission vary greatly from object to object. A control sample shows little evidence for spatially resolved forbidden O III profile substructure. The forbidden O III components usually have high excitation. The component velocities can fall well outside the maximum galactic rotation amplitude and, in some cases, are opposite to the sense of rotation. This strongly suggests that the component gas does not rotate with the rest of the galactic gas but is instead undergoing systematic outflow. 47 references.
Boundary Layer Influence on the Unsteady Horseshoe Vortex Flow and Surface Heat Transfer

The spatial-temporal flow field and associated surface heat transfer within the leading edge, end-wall region of a bluff body were examined using both particle image velocimetry and thermochromic liquid crystal temperature measurements. The horseshoe vortex system in the end-wall region is mechanistically linked to the upstream boundary layer unsteadiness. Hairpin vortex packets, associated with turbulent boundary layer bursting behavior, amalgamate with the horseshoe vortex resulting in unsteady strengthening and streamwise motion. The horseshoe vortex unsteadiness exhibits two different natural frequencies: one associated with the transient motion of the horseshoe vortex and the other with the transient surface heat transfer. Comparable unsteadiness occurs in the end-wall region of the more complex airfoil geometry of a linear turbine cascade. To directly compare the horseshoe vortex behavior around a turning airfoil to that of a simple bluff body, a length scale based on the maximum airfoil thickness is proposed.
Ultra-wideband polarization conversion metasurfaces based on multiple plasmon resonances

We propose to realize ultra-wideband polarization conversion metasurfaces in microwave regime through multiple plasmon resonances. An ultra-wideband polarization conversion metasurface is designed using a double-head arrow structure and is further demonstrated both numerically and experimentally. Four plasmon resonances are generated by electric and magnetic resonances, which lead to bandwidth expansion of cross-polarization reflection. The simulated results show that the maximum conversion efficiency is nearly 100% at the four plasmon resonance frequencies and a 1:4 3 dB bandwidth can be achieved for both normally incident x- and y-polarized waves. Experimental results agree well with simulation ones.
The Pulsar Content of Globular Clusters

Recent surveys of Galactic globular clusters have been very effective at discovering radio pulsars. By a careful analysis of selection effects in the various surveys, and after estimating the relative efficiency of pulsar production in the individual clusters, a census of the cluster population of pulsars is obtained. It is found that there are about 10,000 pulsars in the Galactic globular clusters, subject to uncertainties in pulsar beaming and binarity. Such a large population poses severe problems for the standard model of pulsar production in clusters, unless the uncertain factors due to beaming and binary are pushed to values inconsistent with the present expectations. This suggests the need for a substantial modification of the standard model, either by including accretion-induced collapse of massive white dwarfs or by increasing the retention of primordial neutron stars in the clusters. 55 refs.
Characterization of the redox status of cancer patients through the d-ROMs and BAP test and correlation of these parameters with blood variables

Oxidative distress and inflammation are common biochemical disorders in individuals with cancer. The measurement of oxidative stress in oncology can be useful in clinical practice to monitor the effectiveness of therapy and unwanted effects of the treatment. Thus, the aim of the present study was to evaluate the redox status through the reactive oxygen metabolites (d-ROMs) and biological antioxidant potential (BAP) tests and investigate the correlations of these parameters with blood variables in cancer patients. This is an observational, retrospective study of analysis of medical records of patients evaluated the period from 2018 to 2020 in an integrative medicine center. The inclusion criteria were individuals of both sexes, over 18 years of age, diagnosed with cancer who performed the d-ROMs and BAP test in the same period of blood analysis. Following the inclusion criteria, the final sample of the study were 57 individuals, 60% were woman and 40% were men. The evaluation of redox state showed that the d-ROMs were high (420.2 {+/-} 112.1 U CARR) in total sample and higher in women compared to male (p < 0.01) and BAP tests were normal (2332 {+/-} 812 mol/l). The oxidative parameters, d-ROMs and OSI, was correlated positively with BAP, red cell distribution width (only d-ROMs), platelets (Plt), C-reactive protein (CRP), erythrocyte sedimentation (ESR) and negatively with hemoglobin (Hb) and mean corpuscular hemoglobin (MCH). Regarding the antioxidant potential index, BAP/dROMs, were correlated positively with Hb and serum albumin (HAS) and negatively correlated with Plt, CRP and ESR. The study shows that redox status of an individual with cancer is altered, and it is possible to monitor this system in clinical practice through d-ROMs and BAP test. These parameters, in addition to being suitable for assessing oxidative stress, were correlated with parameters predictors of inflammation.
Marangoni instability of a thin liquid film heated from below by a local heat source

We consider the motion of a liquid film falling down a heated planar substrate. Using the integral-boundary-layer approximation of the Navier–Stokes/energy equations and free-surface boundary conditions, it is shown that the problem is governed by two coupled nonlinear partial differential equations for the evolution of the local film height and temperature distribution in time and space. Two-dimensional steady-state solutions of these equations are reported for different values of the governing dimensionless groups. Our computations demonstrate that the free surface develops a bump in the region where the wall temperature gradient is positive. We analyse the linear stability of this bump with respect to disturbances in the spanwise direction. We show that the operator of the linearized system has both a discrete and an essential spectrum. The discrete spectrum bifurcates from resonance poles at certain values of the wavenumber for the disturbances in the transverse direction. The essential spectrum is always stable while part of the discrete spectrum becomes unstable for values of the Marangoni number larger than a critical value. Above this critical Marangoni number the growth rate curve as a function of wavenumber has a finite band of unstable modes which increases as the Marangoni number increases.
Review of phonons in moiré superlattices

Moiré patterns in physics are interference fringes produced when a periodic template is stacked on another similar one with different displacement and twist angles. The phonon in two-dimensional (2D) material affected by moiré patterns in the lattice shows various novel physical phenomena, such as frequency shift, different linewidth, and mediation to the superconductivity. This review gives a brief overview of phonons in 2D moiré superlattice. First, we introduce the theory of the moiré phonon modes based on a continuum approach using the elastic theory and discuss the effect of the moiré pattern on phonons in 2D materials such as graphene and MoS2. Then, we discuss the electron–phonon coupling (EPC) modulated by moiré patterns, which can be detected by the spectroscopy methods. Furthermore, the phonon-mediated unconventional superconductivity in 2D moiré superlattice is introduced. The theory of phonon-mediated superconductivity in moiré superlattice sets up a general framework, which promises to predict the response of superconductivity to various perturbations, such as disorder, magnetic field, and electric displacement field.
Shape Models of Lucy Targets (3548) Eurybates and (21900) Orus from Disk-integrated Photometry

We use our new light curves, along with historical data, to determine the rotation state, photometric properties, and convex shape models of the targets of the Lucy mission (3548) Eurybates and (21900) Orus. We determine a retrograde spin for both targets, with sidereal rotation periods of 8.7027283 ± 0.0000029 h and 13.486190 ± 0.000017 h, respectively. The phase curves of both objects are nearly linear in the phase-angle range observable from Earth and lack a pronounced opposition effect. Unsupervised classification of these phase curves by the Penttilä et al. tool suggests that Eurybates and Orus belong to the C and D taxonomic types, respectively, thereby independently confirming past classifications based on their spectral slope. Time-resolved color-index measurements show no systematic color variations correlated with rotation for either target at the 1% level, suggesting that no variegation is present on a hemispherical scale for any of the objects. Comparison of the shape models with stellar occultation data available for the two objects from the program by Buie et al. allows us to resolve the longitude ambiguity of the orientations of the spin axes and derive unique pole solutions for both targets. Furthermore, scaling the shape models to match the occultation chords produces accurate sizes and geometric albedos for both objects. The derived surface-equivalent spherical diameters are D s = 69.3 ± 1.4 km and D s = 60.5 ± 0.9 km for Eurybates and Orus, respectively, while the geometric albedo in the H, G 1, G 2 system is p V (H, G 1, G 2) = 0.044 ± 0.003 and p V (H, G 1, G 2) = 0.040 ± 0.002 for Eurybates and Orus, respectively.
Algebraic isomorphisms and Jordan derivations of -subspace lattice algebras

It is shown that every algebraic isomorphism between standard subalgebras of J -subspace lattice algebras is quasi-spatial and every Jordan derivation of standard subalgebras of J -subspace lattice algebras is an additive derivation. Also, it is proved that every finite rank operator in a J -subspace lattice algebra can be written as a finite sum of rank one operators each belonging to that algebra. As an additional result, a multiplicative bijection of a J -subspace lattice algebra onto an arbitrary ring is proved to be automatically additive. Those results can be applied to atomic Boolean subspace lattice algebras and pentagon subspace lattice algebras.
Lower-hybrid wave cavities detected by instrumented spacecrafts

Localized electrostatic wave packets in the frequency region of lower-hybrid waves have been detected by instrumented rocket payloads and recently also by the instruments on the FREJA satellite. These waves are often associated with local density depletions, indicating that the structures can be interpreted as wave-filled cavities which are strongly elongated along the magnetic field. The basic features of the observations are discussed. Based on simple statistical arguments, we attempt to present some characteristics which have to be accommodated within an ultimate theory describing the observed wave phenomena.
Properties and Origin of Asymmetric and Unusual Stokes V Profiles Observed in Solar Magnetic Fields

Between 5% and 10% of Stokes V profiles observed outside of sunspots with the High Altitude Observatory/National Solar Observatory Advanced Stokes Polarimeter are of unusual shape. We categorize them as follows. Normal profiles have two wings of opposite sign that typically show an asymmetry between both lobes. Single-lobed profiles have an amplitude above the noise level only for one wing. Single-lobed profiles occur because of a strong asymmetry between the red and blue wings in combination with low signal amplitude and the limited sensitivity of the measurement. The strongest verifiable amplitude asymmetry found is 90%. Mixed-polarity profiles are the most common type of unusual profiles. These profiles can occur because of the unresolved mixture of polarities in the solar atmosphere on spatial scales ≤600 km or because of the spreading of V signals due to seeing and diffraction. Single-lobed profiles and mixed polarities are mainly found outside high magnetic flux areas. Dynamic profiles consist of two or more superposed components with large Doppler shifts relative to each other. They are mainly observed in an emerging flux region. The measured relative Doppler shifts range up to 18 km s-1, indicating upward and downward moving shocks in magnetic fields. We propose two possible configurations for network and plage fields: (1) a mixture of intense kilogauss flux tubes and a more turbulent subkilogauss field and (2) return flux in the form of weak fields surrounding isolated flux tubes and at the edges of flux tube clusters. Both configurations are supported by the analysis of V profiles in the vicinity of an isolated kilogauss flux tube. We find that the use of low-order adaptive optics reduces the uncertainties in interpreting Stokes data.
Observation of pressure stimulated voltages in rocks using an electric potential sensor

Recent interest in the electrical activity in rock and the use of electric field transients as candidates for earthquake precursors has led to studies of pressure stimulated currents in laboratory samples. In this paper, an electric field sensor is used to measure directly the voltages associated with these currents. Stress was applied as uniaxial compression to marble and granite at an approximately constant rate. In contrast with the small pressure stimulated currents previously measured, large voltage signals are reported. Polarity reversal of the signal was observed immediately before fracture for the marble, in agreement with previous pressure stimulated current studies.