Miracle-dz/UniFAR-FTUs huggingface dataset:
On the Origin of Bimodal Horizontal Branches in Massive Globular Clusters: The Case of NGC 6388 and NGC 6441

Despite the efforts of the past decade, the origin of the bimodal horizontal branch (HB) found in some globular clusters (GCs) remains a conundrum. Inspired by the discovery of multiple stellar populations in the most massive Galactic GC, ω Centauri, we investigate the possibility that two distinct populations may coexist and are responsible for the bimodal HBs in the third and fifth brightest GCs, NGC 6388 and NGC 6441. Using the population synthesis technique, we examine two different chemical “self-enrichment” hypotheses in which a primordial GC was sufficiently massive to contain two or more distinct populations as suggested by the populations found in ω Cen: (1) the age-metallicity relation scenario in which two populations with different metallicity and age coexist, following an internal age-metallicity relation, and (2) the super-helium-rich scenario in which GCs contain a certain fraction of helium-enhanced stars, for instance, the second-generation stars formed from the helium-enriched ejecta of the first. The comparative study indicates that the detailed color-magnitude diagram morphologies and the properties of the RR Lyrae variables in NGC 6388 and NGC 6441 support the latter scenario: i.e., the model which assumes a minor fraction (~15%) of helium excess (Y≃ 0.3) stars. The results suggest that helium content is the main driver behind the HB bimodality found most often in massive GCs. If confirmed, the GC-to-GC variation of helium abundance should be considered a local effect, further supporting the argument that age is the global second parameter of HB morphology.
RACE-OC project: Rotation and variability of young stellar associations within 100 pc

Context. Examining the angular momentum of stars and its interplay with their magnetic fields represent a promising way to probe the stellar internal structure and evolution of low-mass stars. Aims. We attempt to determine the rotational and magnetic-related activity properties of stars at different stages of evolution.We focused our attention primarily on members of clusters and young stellar associations of known ages. In this study, our targets are 6 young loose stellar associations within 100 pc and with ages in the range 8-70 Myr: TW Hydrae (~8 Myr), β Pictoris (~10 Myr), Tucana/Horologium, Columba, Carina (~30 Myr), and AB Doradus (~70 Myr). Additional rotational data for α Persei and the Pleiades from the literature are also considered. Methods. Rotational periods of stars exhibiting rotational modulation due to photospheric magnetic activity (i.e., starspots) were determined by applying the Lomb-Scargle periodogram technique to photometric time-series data obtained by the All Sky Automated Survey (ASAS). The magnetic activity level was derived from the amplitude of the V lightcurves. The statistical significance of the rotational evolution at different ages was inferred by applying a two-sided Kolmogorov-Smirnov test to subsequent age-bins. Results. We detected the rotational modulation and measured the rotation periods of 93 stars for the first time, and confirmed the periods of 41 stars already known from the literature. For an additional 10 stars, we revised the period determinations by other authors. The sample was augmented with periods of 21 additional stars retrieved from the literature. In this way, for the first time we were able to determine the largest set of rotation periods at ages of ~8, ~10 and ~30 Myr, as well as increase by 150% the number of known periodic members of AB Dor. Conclusions. The analysis of the rotation periods in young stellar associations, supplemented by Orion Nebula Cluster (ONC) and NGC 2264 data from the literature, has allowed us to find that in the 0.6-1.2 M ⊙ range the most significant variations in the rotation period distributipn are the spin-up between 9 and 30 Myr and the spin-down between 70 and 110 Myr. Variations of between 30 and 70 Myr are rather doubtful, despite the median period indicating a significant spin-up. The photospheric activity level is found to be correlated with rotation at ages greater than ~70 Myr and to show some additional age dependence besides that related to rotation and mass.
ON THE INTRINSIC CONTINUUM LINEAR POLARIZATION OF CLASSICAL Be STARS: THE EFFECTS OF METALLICITY AND ONE-ARMED DENSITY PERTURBATIONS

We report on the effects of two disk properties on the continuum linear polarization signature of classical Be stars. First, we investigate the effect of including metallicity in computing the thermal structure of the circumstellar gas on the resulting polarimetric Balmer jump. The Balmer jump is a distinguishing feature of the polarization signature in these objects and, as such, can be used as a tool for differentiating classical Be stars from similar Hα-emitters identified through conventional photometric techniques. We find that although low-metallicity environments will have hotter disk temperatures on average, the temperature change alone cannot account for the discrepancy in the frequency of Balmer jumps between low-metallicity and solar-metallicity stellar populations. Second, we investigate the effect of including a global one-armed oscillation in the gas density distribution of the modeled disk. We find that a non-axisymmetric perturbation pattern yields discernible variations in the predicted polarization level. If these density oscillations are present in the inner region of classical Be star disks, the polarimetric variations should produce a periodic signature which can help characterize the dynamical nature of the gas near the star.
Influence e-word of mouth and brand awareness to loyalty brand on era pandemic year 2020

The study aimed to know the influence of e-word of mouth and brand awareness on loyalty in the pandemic era year 2020 (study case on consumer service wedding organizer in Palembang city). The study population is consumers who use service wedding organizers in the town of Palembang year 2020. Selected respondents in the study is para consumer who bought service wedding organizers during the pandemic era in South Sumatra province. As many as 154 respondents with using the non-probability sampling technique. The multiple linear regression analysis shows that E-word of mouth and brand awareness positively and significantly affect loyalty. Show c image very influential wedding organizer in creating a good image with gift review to services that have been used. Give service customer relations to build good connections with consumers who have used it Becomes important for giving impressions, messages, and feedback to services that have been given after-sales service to consumers who have used service wedding organizers to shape concern or addiction service customer relations.
US Adults’ Likelihood to Participate in Dementia Prevention Drug Trials: Results from the National Poll on Healthy Aging

Background Recruitment to dementia prevention clinical trials is challenging, and participants are not representative of US adults at risk. A better understanding of the general public’s interest in dementia prevention research participation is needed to inform future recruitment strategies. Objective To examine US adults’ characteristics associated with self-reported likelihood to participate in dementia prevention clinical trials. Design We conducted a cross-sectional survey using the October 2018 wave of the University of Michigan National Poll on Healthy Aging. Setting The National Poll on Healthy Aging is a nationally representative survey of adults using KnowledgePanel (Ipsos Public Affairs LLC), a probability-based panel of the civilian, noninstitutionalized US population. Participants We analyzed data from 1,028 respondents, ages 50 to 64 years, who completed a web survey module on brain health. Measurements We used logistic regression models to examine associations between sociodemographic and dementia-related factors (e.g., family history) and self-reported likelihood to participate in a dementia prevention clinical trial of a new medicine (“very” or “somewhat likely” vs. “not likely” survey responses). Among respondents not likely to participate, we examined frequency of reasons endorsed for this decision, stratified by age, sex, and race and ethnicity. Results Of the 1,028 respondents, half were female, 68% Non-Hispanic White, 13% Hispanic, and 12% Non-Hispanic Black. Twelve percent of respondents reported being very likely to participate in a dementia prevention trial, 32% somewhat likely, and 56% not likely. Factors associated with higher likelihood to participate were higher perceived risk of dementia [OR, 2.17 (95% CI, 1.61, 2.93)], a positive family history of dementia [OR, 1.75 (95% CI, 1.27, 2.43)], and having discussed dementia prevention with a doctor [OR, 2.20 (95% CI, 1.10, 4.42)]. There were no differences in likelihood to participate by sociodemographic characteristics. Among 570 respondents not likely to participate, 39% said they did not want to be a guinea pig, 23% thought dementia would not affect them, 22% thought there would be too high a chance for harm, 15% indicated study participation would take too much time, and 5% reported fear of learning information about oneself. There were no differences across age, sex, and racial and ethnic groups. Conclusions In this study, perceived risk of dementia, family history, and discussion of prevention with a doctor were associated with likelihood to participate in a dementia prevention clinical trial, whereas sociodemographic factors including race and ethnicity were not. Findings suggest that recruitment interventions focused on increasing knowledge of dementia risk and prevention trials and involving healthcare providers may be effective tools to improve enrollment rates, regardless of target community.
Normal modes and localization in nonlinear systems

Preface A.F. Vakakis. Invariant Manifolds, Nonclassical Normal Modes, and Proper Orthogonal Modes in the Dynamics of the Flexible Spherical Pendulum I.T. Georgiou, I.B. Schwartz. Normal Vibrations in Near-Conservative Self-Excited and Viscoelastic Nonlinear Systems Y.V. Mikhlin, B.I. MorgunovDAGGER. Nonlinear Normal Modes in a System with Nonholonomic Constraints R.H. Rand, D.V. Ramani. Nonlinear Normal Modes of a Parametrically Excited Cantilever Beam H. Yabuno, A.H. Nayfeh. Normal Modes and Boundary Layers for a Slender Tensioned Beam on a Nonlinear Foundation F. Pellicano, A.F. Vakakis. The Description of Localized Normal Modes in a Chain of Nonlinear Coupled Oscillators Using Complex Variables L.I. Manevitch. Spatially Localized Models of Extended Systems R.W. Wittenberg, P. Holmes. Mode Localization in Dynamics and Buckling of Linear Imperfect Continuous Structures A. Luongo. Dynamics of Relative Phases: Generalised Multibreathers T. Ahn, R.S. Mackay, J.-A. Sepulchre. Nonlinear Modal Analysis of Structural Systems Using Multi-Mode Invariant Manifolds E. Pesheck, N. Boivin, C. Pierre, S.W. Shaw. Localization in Nonlinear Mistuned Systems with Cyclic Summetry W. Sextro, K. Popp, T. Krzyzynski. Mode Localization Induced by a Nonlinear Control Loop R.T. M'Closkey, A. Vakakis, R. Gutierrez. Transition of Energy to a Nonlinear Localized Mode in a Highly Asymmetric System of Two Oscillators O.V. Gendelman. Application of Nonlinear Normal Mode Analysis to the Non-linear and Coupled Dynamics of a Floating Offshore Platform with Damping J.M. Falzarano, R.E. Clague, R.S. Kota. Performance of Nonlinear Vibration Absorbers for Multi-Degrees-of-Freedom Systems Using Nonlinear Normal Modes G.S. Agnes, D.J. Inman.
Persistence probabilities \& exponents

This article deals with the asymptotic behaviour as $t\to +\infty$ of the survival function $P[T > t],$ where $T$ is the first passage time above a non negative level of a random process starting from zero. In many cases of physical significance, the behaviour is of the type $P[T > t]=t^{-\theta + o(1)}$ for a known or unknown positive parameter $\theta$ which is called a persistence exponent. The problem is well understood for random walks or L\'evy processes but becomes more difficult for integrals of such processes, which are more related to physics. We survey recent results and open problems in this field.
Optimal constraint on gNL from CMB

An optimal method to constrain the non-linearity parameter gNL of the local-type non-Gaussianity from CMB data is proposed. Our optimal estimator for gNL is separable and can be efficiently computed in real space. Combining the exact filtering of CMB maps with the full covariance matrix, our method allows us to extract cosmological information from observed data as much as possible and obtain a tighter constraint on gNL than previous studies. Applying our method to the WMAP 9-year data, we obtain the constraint gNL = (−3.3±2.2) × 105, which is a few times tighter than previous ones. We also make a forecast for PLANCK data by using the Fisher matrix analysis.
The CO luminosity and CO-H2 conversion factor of diffuse ISM: does CO emission trace dense molecular gas?

Aims. We wish to separate and quantify the CO luminosity and CO-H2 conversion factor applicable to diffuse but partially-molecular ISM when H2 and CO are present but C + is the dominant form of gas-phase carbon. Methods. We discuss galactic lines of sight observed in Hi ,H CO + and CO where CO emission is present but the intervening clouds are diffuse (locally AV < 1 mag) with relatively small CO column densities NCO < 2 × 10 16 cm −2 . We separate the atomic and molecular fractions statistically using EB−V as a gauge of the total gas column density and compare NH2 to the observed CO brightness. Results. Although there are H2-bearing regions where CO emission is too faint to be detected, the mean ratio of integrated CO brightness to NH2 for diffuse ISM does not differ from the usual value of 1 K km s −1 of integrated CO brightness per 2 × 10 20 H2 cm −2 . Moreover, the luminosity of diffuse CO viewed perpendicular to the galactic plane is 2/3 that seen at the Solar galactic radius in surveys of CO emission near the galactic plane. Conclusions. Commonality of the CO-H2 conversion factors in diffuse and dark clouds can be understood from considerations of radiative transfer and CO chemistry. There is unavoidable confusion between CO emission from diffuse and dark gas and misattribution of CO emission from diffuse to dark or giant molecular clouds. The character of the ISM is different from what has been believed if CO and H2 that have been attributed to molecular clouds on the verge of star formation are actually in more tenuous, gravitationally-unbound diffuse gas.
STELLAR COLLISIONS AND BLUE STRAGGLER STARS IN DENSE GLOBULAR CLUSTERS

Blue straggler stars (BSSs) are abundantly observed in all Galactic globular clusters (GGCs) where data exist. However, observations alone cannot reveal the relative importance of various formation channels or the typical formation times for this well-studied population of anomalous stars. Using a state-of-the-art Hénon-type Monte Carlo code that includes all relevant physical processes, we create 128 models with properties typical of the observed GGCs. These models include realistic numbers of single and binary stars, use observationally motivated initial conditions, and span large ranges in central density, concentration, binary fraction, and mass. Their properties can be directly compared with those of observed GGCs. We can easily identify the BSSs in our models and determine their formation channels and birth times. We find that for central densities above ∼103 M☉ pc−3, the dominant formation channel is stellar collisions, while for lower density clusters, mass transfer in binaries provides a significant contribution (up to 60% in our models). The majority of these collisions are binary-mediated, occurring during three-body and four-body interactions. As a result, a strong correlation between the specific frequency of BSSs and the binary fraction in a cluster can be seen in our models. We find that the number of BSSs in the core shows only a weak correlation with the collision rate estimator Γ traditionally used by observers, in agreement with the latest Hubble Space Telescope Advanced Camera for Surveys data. Using an idealized “full mixing” prescription for collision products, our models indicate that the BSSs observed today may have formed several Gyr ago. However, denser clusters tend to have younger (∼1 Gyr) BSSs.
Classification of Monkeypox Images Based on Transfer Learning and the Al-Biruni Earth Radius Optimization Algorithm

The world is still trying to recover from the devastation caused by the wide spread of COVID-19, and now the monkeypox virus threatens becoming a worldwide pandemic. Although the monkeypox virus is not as lethal or infectious as COVID-19, numerous countries report new cases daily. Thus, it is not surprising that necessary precautions have not been taken, and it will not be surprising if another worldwide pandemic occurs. Machine learning has recently shown tremendous promise in image-based diagnosis, including cancer detection, tumor cell identification, and COVID-19 patient detection. Therefore, a similar application may be implemented to diagnose monkeypox as it invades the human skin. An image can be acquired and utilized to further diagnose the condition. In this paper, two algorithms are proposed for improving the classification accuracy of monkeypox images. The proposed algorithms are based on transfer learning for feature extraction and meta-heuristic optimization for feature selection and optimization of the parameters of a multi-layer neural network. The GoogleNet deep network is adopted for feature extraction, and the utilized meta-heuristic optimization algorithms are the Al-Biruni Earth radius algorithm, the sine cosine algorithm, and the particle swarm optimization algorithm. Based on these algorithms, a new binary hybrid algorithm is proposed for feature selection, along with a new hybrid algorithm for optimizing the parameters of the neural network. To evaluate the proposed algorithms, a publicly available dataset is employed. The assessment of the proposed optimization of feature selection for monkeypox classification was performed in terms of ten evaluation criteria. In addition, a set of statistical tests was conducted to measure the effectiveness, significance, and robustness of the proposed algorithms. The results achieved confirm the superiority and effectiveness of the proposed methods compared to other optimization methods. The average classification accuracy was 98.8%.
Missing Baryons, from Clusters to Groups of Galaxies

From clusters to groups of galaxies, the powerful bremsstrahlung radiation LX emitted in X-rays by the intracluster plasma is observed to decline sharply with lowering virial temperatures T (i.e., at shallower depths of the gravitational wells) after a steep local LX − T correlation; this implies increasing scarcity of diffuse baryons relative to dark matter, well under the cosmic fraction. We show how the widely debated issue concerning these “missing baryons” is solved in terms of the thermal and/or dynamical effects of the kinetic (at low redshifts z) and radiative (at high z) energy inputs from central active galactic nuclei, of which independent evidence is being observed. From these inputs we compute shape and z-evolution expected for the LX − T correlation which agree with the existing data, and provide a predictive pattern for future observations.
Compact Q -balls and Q -shells in a scalar electrodynamics

We investigate spherically symmetric nontopological solitons in electrodynamics with a scalar field self-interaction U{approx}|{psi}| taken from the complex signum-Gordon model. We find Q-balls for small absolute values of the total electric charge Q, and Q-shells when |Q| is large enough. In both cases the charge density exactly vanishes outside certain compact regions in the three-dimensional space. The dependence of the total energy E of small Q-balls on the total electric charge has the form E{approx}|Q|{sup 5/6}, while in the case of very large Q-shells, E{approx}|Q|{sup 7/6}.
THE EFFECT OF SPATIAL GRADIENTS IN STELLAR MASS-TO-LIGHT RATIO ON BLACK HOLE MASS MEASUREMENTS

We have tested the effect of spatial gradients in stellar mass-to-light ratio (ϒ) on measurements of black hole masses (M•) derived from stellar orbit superposition models. Such models construct a static gravitational potential for a galaxy and its central black hole, but typically assume spatially uniform ϒ. We have modeled three giant elliptical galaxies with gradients α ≡ dlog (ϒ)/dlog (r) from −0.2 to +0.1. Color and line strength gradients suggest mildly negative α in these galaxies. Introducing a negative (positive) gradient in ϒ increases (decreases) the enclosed stellar mass near the center of the galaxy and leads to systematically smaller (larger) M• measurements. For models with α = −0.2, the best-fit values of M• are 28%, 27%, and 17% lower than the constant-ϒ case, in NGC 3842, NGC 6086, and NGC 7768, respectively. For α = +0.1, M• are 14%, 22%, and 17% higher than the constant-ϒ case for the three respective galaxies. For NGC 3842 and NGC 6086, this bias is comparable to the statistical errors from individual modeling trials. At larger radii, negative (positive) gradients in ϒ cause the total stellar mass to decrease (increase) and the dark matter fraction within one effective radius to increase (decrease).
STEREO measurements of electron acceleration beyond fast Fermi at the bow shock

Solar wind electrons are accelerated and reflected upstream by the terrestrial bow shock into a region known as the electron foreshock. Previously observed electron spectra at low energies are consistent with a fast Fermi mechanism, based on the adiabatic conservation of the magnetic moment ({\mu}) of the accelerated electrons. At higher energies, suprathermal power law tails are observed beyond the level predicted by fast Fermi. The SWEA and STE electron detectors on STEREO enable measurements of foreshock electrons with good energy resolution and sensitivity over the entire foreshock beam. We investigate the electron acceleration mechanism by comparing observed STEREO electron spectra with predictions based on a Liouville mapping of upstream electrons through a shock encounter. The foreshock electron beam extends up to several tens of keV, energies for which the Larmor radii of electrons is tens of km or greater. These radii are comparable to the scale sizes of the shock, and {\mu} conservation no longer applies. We show that the observed enhancement in the foreshock beam beyond fast Fermi levels begins at energies where this assumption breaks down. We also demonstrate, using the Liouville mapping technique, that the strahl plays an important role in the formation of the bump on tail instability. We discuss this in the context of recent observations in the foreshock and in solar wind magnetic holes.