Miracle-dz/UniFAR-FTUs huggingface dataset:
PLASMA HEATING IN SOLAR FLARES AND THEIR SOFT AND HARD X-RAY EMISSIONS

In this paper, the energy budgets of two single-loop-like flares observed in X-ray are analyzed under the assumption that nonthermal electrons (NTEs) are the only source of plasma heating during all phases of both events. The flares were observed by RHESSI and GOES on 2002 February 20 and June 2, respectively. Using a one-dimensional (1D) hydrodynamic code for both flares, the energy deposited in the chromosphere was derived applying RHESSI observational data. The use of the Fokker–Planck formalism permits the calculation of distributions of the NTEs in flaring loops and thus spatial distributions of the X-ray nonthermal emissions and integral fluxes for the selected energy ranges that were compared with the observed ones. Additionally, a comparative analysis of the spatial distributions of the signals in the RHESSI images was conducted for the footpoints and for all the flare loops in selected energy ranges with these quantities' fluxes obtained from the models. The best compatibility of the model and observations was obtained for the 2002 June 2 event in the 0.5–4 Å GOES range and total fluxes in the 6–12 keV, 12–25 keV, 20–25 keV, and 50–100 keV energy bands. Results of photometry of the individual flaring structures in a high energy range show that the best compliance occurred for the 2002 June 2 flare, where the synthesized emissions were at least 30% higher than the observed emissions. For the 2002 February 20 flare, synthesized emission is about four times lower than the observed one. However, in the low energy range the best conformity was obtained for the 2002 February 20 flare, where emission from the model is about 11% lower than the observed one. The larger inconsistency occurs for the 2002 June 2 solar flare, where synthesized emission is about 12 times greater or even more than the observed emission. Some part of these differences may be caused by inevitable flaws of the applied methodology, like by an assumption that the model of the flare is symmetric and there are no differences in the emissions originating from the feet of the flares loop and by relative simplicity of the applied numerical 1D code and procedures. No doubt a significant refinement of the applied numerical models and more sophisticated implementation of the various physical mechanisms involved are required to achieve a better agreement. Despite these problems, a collation of modeled results with observations shows that soft and hard X-ray emissions observed for analyzed single-loop-like events may be fully explained by electron-beam-driven evaporation only.
A closed-form necessary and sufficient condition for any two-qubit state to show hidden nonlocality w.r.t the Bell-CHSH inequality

In this note, we discuss a closed-form necessary and sufficient condition for any two-qubit state to show hidden nonlocality w.r. t the Bell-CHSH inequality. This is then used to numerically compute the relative volume of states showing hidden Bell-CHSH non-locality , among all two-qubit states with one-sided reduction maximally mixed.
SUPERNOVAE IN THE CENTRAL PARSEC: A MECHANISM FOR PRODUCING SPATIALLY ANISOTROPIC HYPERVELOCITY STARS

Several tens of hypervelocity stars (HVSs) have been discovered escaping our Galaxy. These stars share a common origin in the Galactic center and are distributed anisotropically in Galactic longitude and latitude. We examine the possibility that HVSs may be created as the result of supernovae (SNe) occurring within binary systems in a disk of stars around Sgr A* over the last 100 Myr. Monte Carlo simulations show that the rate of binary disruption is ∼10−4 yr−1, comparable to that of tidal disruption models. The SN-induced HVS production rate (ΓHVS) is significantly increased if the binaries are hardened via migration through a gaseous disk. Moderate hardening gives ΓHVS ≃ 2 × 10−7 yr−1 and an estimated population of ∼20 HVSs in the last 100 Myr. SN-induced HVS production requires the internal and external orbital velocity vectors of the secondary binary component to be aligned when the binary is disrupted. This leaves an imprint of the disk geometry on the spatial distribution of the HVSs, producing a distinct anisotropy.
Cosmology in nonrelativistic general covariant theory of gravity

Horava and Melby-Thompson recently proposed a new version of the Horava-Lifshitz theory of gravity, in which the spin-0 graviton is eliminated by introducing a Newtonian prepotential {phi} and a local U(1) gauge field A. In this paper, we first derive the corresponding Hamiltonian, supermomentum constraints, the dynamical equations, and the equations for {phi} and A, in the presence of matter fields. Then, we apply the theory to cosmology and obtain the modified Friedmann equation and the conservation law of energy, in addition to the equations for {phi} and A. When the spatial curvature is different from zero, terms behaving like dark radiation and stiff-fluid exist, from which, among other possibilities, a bouncing universe can be constructed. We also study linear perturbations of the Friedmann-Robertson-Walker universe with any given spatial curvature k, and we derive the most general formulas for scalar perturbations. The vector and tensor perturbations are the same as those recently given by one of the present authors [A. Wang, Phys. Rev. D 82, 124063 (2010). ] in the setup of Sotiriou, Visser, and Weinfurtner. Applying these formulas to the Minkowski background, we have shown explicitly that the scalar and vector perturbations of the metric indeed vanish, and the onlymore » remaining modes are the massless spin-2 gravitons. « less
A new candidate Wolf-Rayet X-ray binary in NGC 253

ABSTRACT We have discovered a persistent, but highly variable X-ray source in the nearby star-burst galaxy NGC 253. The source varies at the level of a factor of about 5 in countrate on timescales of a few hours. Two long observations of the source with Chandraand XMM-Newton show suggestive evidence for the source having a period of about14-15 hours, but the time sampling in existing data is insuﬃcient to allow a ﬁrmdetermination that the source is periodic. Given the amplitude of variation and thelocation in a nuclear starburst, the source is likely to be a Wolf-Rayet X-ray binary,with the tentative period being the orbital period of the system. In light of the factthat we have demonstrated that careful examination of the variability of moderatelybright X-ray sources in nearby galaxies can turn up candidate Wolf-Rayet X-ray bi-naries, we discuss the implications of Wolf-Rayet X-ray binaries for predictions of thegravitational wave source event rate, and, potentially, interpretations of the events.Key words: X-rays:binaries – galaxies:individual:NGC 253 – galaxies:starburst –stars:Wolf-Rayet
Abelian and Non-Abelian Statistics in the Coherent State Representation

We further develop an approach to identify the braiding statistics associated to a given fractional quantum Hall state through adiabatic transport of quasiparticles. This approach is based on the notion of adiabatic continuity between quantum Hall states on the torus and simple product states—or patterns—in the thin torus limit, together with a suitable coherent state ansatz for localized quasiholes that respects the modular invariance of the torus. We give a refined and unified account of the application of this method to the Laughlin and Moore-Read states, which may serve as a pedagogical introduction to the nuts and bolts of this technique. Our main result is that the approach is also applicable—without further assumptions—to more complicated non-Abelian states. We demonstrate this in great detail for the level k ¼ 3 Read-Rezayi state at filling factor � ¼ 3=2. These results may serve as an independent check of other techniques, where the statistics are inferred from conformal block monodromies. Our approach has the benefit of giving rise to intuitive pictures representing the transformation of topological sectors during braiding, and allows for a self-consistent derivation of non-Abelian statistics without heavy mathematical machinery.
Peak energy of the prompt emission of long gamma-ray bursts versus their fluence and peak flux

The spectral-energy (and luminosity) correlations in long gamma-ray bursts are being hotly debated to establish, first of all, their reality against possible selection effects. These are best studied in the observer planes, namely the peak energy E obs peak versus the fluence F or the peak flux P. In a recent paper, we have started to investigate this problem considering all bursts with known redshift and spectral properties. Here, we consider instead all bursts with known E obs peak , irrespective of redshift, adding to those a sample of 100 faint BATSE bursts representative of a larger population of 1000 objects. This allows us to construct a complete, fluence-limited, sample, tailored to study the selection/instrumental effects we consider. We found that the fainter BATSE bursts have smaller E obs peak than those of bright events. As a consequence, the E obs peak of these bursts is correlated with the fluence, though with a slope flatter than that defined by bursts with z. Selection effects, which are present, are shown not to be responsible for the existence of such a correlation. About six per cent of these bursts are surely outliers of the E peak -E iso correlation (updated in this paper to include 83 bursts), since they are inconsistent with it for any redshift. E obs peak also correlates with the peak flux, with a slope similar to the Ep eak -L iso correlation. In this case, there is only one sure outlier. The scatter of the E obs peak -P correlation defined by the BATSE bursts of our sample is significantly smaller than the E obs peak -F correlation of the same bursts, while for the bursts with known redshift the E peak -E iso correlation is tighter than the E peak -L iso one. Once a very large number of bursts with E obs peak and redshift will be available, we thus expect that the E peak -L iso correlation will be similar to that currently found, whereas it is very likely that the E peak -E iso correlation will become flatter and with a larger scatter.
The effect of asymmetric disorder on the diffusion in arbitrary networks

Considering diffusion in the presence of asymmetric disorder, an exact relationship between the strength of weak disorder and the electric resistance of the corresponding resistor network is revealed, which is valid in arbitrary networks. This implies that the dynamics are stable against weak asymmetric disorder if the resistance exponent ζ of the network is negative. In the case of ζ>0, numerical analyses of the mean first-passage time τ on various fractal lattices show that the logarithmic scaling of τ with the distance l, ln τ∼lψ, is a general rule, characterized by a new dynamical exponent ψ of the underlying lattice.
The cosmic evolution of the IMF under the Jeans conjecture with implications for massive galaxies

We examine the cosmic evolution of a stellar initial mass function (IMF) in galaxies that varies with the Jeans mass in the interstellar medium, paying particular attention to the Kband stellar mass to light ratio (M/LK) of present-epoch massive galaxies. We calculate the typical Jeans mass using high-resolution hydrodynamic simulations coupled with a fully radiative model for the ISM, which yields a parameterisation of the IMF characteristic mass as a function of galaxy star formation rate (SFR). We then calculate the star formation histories of galaxies utilising an equilibrium galaxy growth model coupled with constraints on the star formation histories set by abundance matching models. We fin d that at early times, energetic coupling between dust and gas drive warm conditions in the ISM, yielding bottom-light/topheavy IMFs associated with large ISM Jeans masses for massive star-forming galaxies. Owing to the remnants of massive stars that formed during the top-heavy phases at early times, the resultant M/LK(σ) in massive galaxies at the present epoch is increased relative to the nonvarying IMF case. At late times, lower cosmic ray fluxes allow for cooler ISM temperatures in massive galaxies, and hence newly formed clusters will exhibit bottom-heavy IMFs, further increasing M/LK(σ). Our central result is hence that a given massive galaxy may go through both top-heavy and bottom-heavy IMF phases during its lifetime, though the bulk of the stars form during a top-heavy phase. Qualitatively, the variations in M/LK(σ) with galaxy mass are in agreement with observations, however, our model may not be able to account for bottom-heavy mass functions as indicated by stellar absorption features.
Observations of the Icy Universe

Freeze-out of the gas-phase elements onto cold grains in dense interstellar and circumstellar media builds up ice mantles consisting of molecules that are mostly formed in situ (H2O, NH3, CO2, CO, CH3OH, and more). This review summarizes the detected infrared spectroscopic ice features and compares the abundances across Galactic, extragalactic, and Solar System environments. A tremendous amount of information is contained in the ice band profiles. Laboratory experiments play a critical role in the analysis of the observations. Strong evidence is found for distinct ice formation stages, separated by CO freeze-out at high densities. The ice bands have proven to be excellent probes of the thermal history of their environment. The evidence for the long-held idea that processing of ices by energetic photons and cosmic rays produces complex molecules is weak. Recent state-of-the-art observations show promise for much progress in this area with planned infrared facilities.
Dual-Sensor Signals Based Exact Gaussian Process-Assisted Hybrid Feature Extraction and Weighted Feature Fusion for Respiratory Rate and Uncertainty Estimations

Accurately estimating respiratory rate (RR) has become essential for patients and the elderly. Hence, we propose a novel method that uses exact Gaussian process regression (EGPR)-assisted hybrid feature extraction and feature fusion based on photoplethysmography and electrocardiogram signals to improve the reliability of accurate RR and uncertainty estimations. First, we obtain the power spectral features and use the multi-phase feature model to compensate for insufficient input data. Then, we combine four different feature sets and choose features with high weights using a robust neighbor component analysis. The proposed EGPR algorithm provides a confidence interval representing the uncertainty. Therefore, the proposed EGPR algorithm, including hybrid feature extraction and weighted feature fusion, is an excellent model with improved reliability for accurate RR estimation. Furthermore, the proposed EGPR methodology is likely the only one currently available that provides highly stable variation and confidence intervals. The proposed EGPR-MF, 0.993 breath per minute (bpm), and EGPR-feature fusion, 1.064 (bpm), show the lowest mean absolute error compared to the other models.
Patient-Specific Instruments for Forearm Sarcoma Resection and Allograft Reconstruction in Children: Results in 4 Cases

For pediatric malignant bone tumors located in the limbs, limb salvage surgery is the gold standard, but it requires adequate resection margins to avoid local recurrence. Primitive bone sarcomas of the forearm (radius or ulna) are very rare and the reconstruction remains challenging. We describe a method to ensure minimal but adequate resection bone margins with precision in four consecutive patients with primitive bone sarcomas of the forearm. During the preoperative planning, magnetic resonance imaging (MRI) was used to delineate the tumor and the tumor volume was transferred to computerized tomography (CT) by image fusion. A patient-specific instrument (PSI) was manufactured by 3D printing to allow the surgeon to perform the surgical cuts precisely according to the preoperative planning. The first PSI was used for the resection of the tumor, which adopted a unique position at the bony surface. A second PSI was intended for the cutting of the bone allograft so that it fitted perfectly with the bone defect. In all four cases, the safe margin obtained into the bone was free of tumor (R0: microscopically margin-negative resection). The functional result was very good in all four patients. This limb salvage surgical technique can be applied in forearm bone sarcoma and improves surgical precision while maintaining satisfactory local tumor control. It can also reduce the surgical time and allow a stable osteosynthesis.
A note on the Einstein equation in string theory

We show, using purely classical considerations and logical extrapolation of results belonging to point particle theories, that the metric background ﬁeld in which a string propagates must satisfy an Einstein or an Einstein–like equation. Additionally, there emerge restrictions on the worldsheet curvature, which seems to act as a source for spacetime gravity, even in the absence of other matter ﬁelds.
Tasimelteon for treating non-24-h sleep-wake rhythm disorder

ABSTRACT Introduction: Non-24-h sleep-wake rhythm disorder (non-24) is observed in approximately half of totally blind individuals, a condition caused by their circadian pacemaker in the suprachiasmatic nucleus not being entrained to 24 h due to a lack of light perceptions. These subjects have a progressively delayed circadian cycle each day, non-24 periodically inducing nighttime insomnia and daytime sleepiness. Tasimelteon is a dual melatonin receptor agonist with high affinity for the melatonin 2 receptor, and it entrains endogenous melatonin rhythms and sleep-wake cycles in individuals with non-24. Areas covered: Herein, the authors review the treatment of non-24 with tasimelteon. The authors further compare tasimelteon with other melatonin receptor agonists. Expert opinion: The treatment strategies for non-24 aim to resynchronize the free-running rhythm with the 24 h light-dark cycle. Tasimelteon entrains circadian rhythms and improves the sleep-wake functions of individuals with non-24. Furthermore, the RESET study demonstrated that 20% of patients that discontinued tasimelteon maintained circadian entrainment whereas 90% of those who continued it maintained circadian entrainment. Long-term administration of tasimelteon is safe and well tolerated, and it is the only pharmacological therapy approved by the US Food and Drug Administration and the European Medicines Agency for non-24.
A comprehensive analysis of piezoelectric energy harvesting from bridge vibrations

Piezoelectric energy harvesting from bridge vibrations has the potential to power wireless sensors used for bridge health monitoring. Often, it is necessary to store the harvested energy before it could be used to power the sensor intermittently. However, the behavior of the piezoelectric energy harvester (PEH) with nonlinear interface circuits for energy extraction and storage subject to realistic bridge vibrations has not been fully understood. This work performs a comprehensive analysis on the performance of the PEH subject to the measured railway bridge vibrations and compares the energy stored on a capacitor using four different interface circuits. Firstly, the dynamic characteristics of the railway bridge is analyzed. A cantilevered PEH is then designed and fabricated based on the dynamic characteristics of the bridge. Subsequently, four realistic energy extraction and storage interface circuits, namely, the standard energy harvesting (SEH), synchronized charge extraction (SCE), parallel synchronized switch harvesting on inductor (P-SSHI) and series SSHI (S-SSHI) circuits, are evaluated and compared when the PEH subject to the measured bridge vibrations. The influence of the storage capacitance and the 1st short-circuit natural frequency of the PEH on the stored energy with these four circuits is then discussed. An optimal storage capacitance exists in the systems based on SEH, P-SSHI and S-SSHI circuits. The system based on P-SSHI circuit has the highest efficiency on energy storage. This work provides a technical framework to develop the realistic energy harvesting and storage system for realization of self-powered bridge condition monitoring.
Improving TB infection control in a regional hospital in the Eastern Cape, South Africa

This quality improvement (QI) work was carried out in Cecilia Makiwane Hospital (CMH), a regional public hospital in the Eastern Cape, South Africa (SA). SA has among the highest incidence of tuberculosis (TB) in the world and this is a leading cause of death in SA. Nosocomial infection is an important source of TB transmission. Adherence to TB infection prevention control (IPC) measures in the medical inpatient department was suboptimal at CMH. The overall aim of this QI project was to make sustainable improvements in TB IPC. A multidisciplinary team was formed to undertake a root cause analysis and develop a strategy for change. The main barriers to adherence to IPC measures were limited knowledge of IPC methods and stigma associated with TB. Specifically, the project aimed to increase the number of: ‘airborne precaution’ signs placed above patients’ beds, patients correctly isolated and patients wearing surgical face masks. Four Plan-Do-Study-Act cycles were used. The strategy for change involved education and awareness-raising in different formats, including formal in-service training delivered to nurses and doctors, a hospital-wide TB awareness week with engaging activities and competitions, and a World TB Day provincial solidarity march. Data on adherence to the three IPC measures were collected over an 8-month period. Pre-intervention (October 2016), a mean of 2% of patients wore face masks, 22% were correctly isolated and 12% had an airborne precaution sign. Post-intervention (May 2017), the compliance improved to 17%, 50% and 25%, respectively. There was a large variation in compliance to each measure. Improvement was greatest in the number of patients correctly isolated. We learnt it is important to work with, not in parallel to, existing teams or structures during QI work. On-the-ground training of nurses and clinicians should be undertaken alongside engagement of senior staff members and managers. This improves the chance of change being adopted into hospital policy.
RESONANT SCATTERING AND Lyα RADIATION EMERGENT FROM NEUTRAL HYDROGEN HALOS

With a state-of-the-art numerical method used for solving the integral-differential equation of radiative transfer, we investigate the flux of the Lyα photon ν0 emergent from an optically thick halo containing a central light source. Our focus is on the time-dependent effects of the resonant scattering. We first show that the frequency distribution of photons in the halo is quickly approaching a locally thermalized state around the resonant frequency, even when the mean intensity of the radiation is highly time dependent. Since initial conditions are forgotten during the thermalization, some features of the flux, such as the two-peak structure of its profile, are actually independent of the intrinsic width and time behavior of the central source, if the emergent photons are mainly from photons in the thermalized state. In this case, the difference |ν± − ν0|, where ν± are the frequencies of the two peaks of the flux, cannot be less than 2 times the Doppler broadening. We then study the radiative transfer in the case where the light emitted from the central source is a flash. We calculate the light curves of the flux from the halo. It shows that the flux is still a flash. The time duration of the flash for the flux, however, is independent of the original time duration of the light source but depends on the optical depth of the halo. Therefore, the spatial transfer of resonant photons is a diffusion process, even though it is not a purely Brownian diffusion. This property enables an optically thick halo to trap and store thermalized photons around ν0 for a long time after the cessation of the central source emission. The photons trapped in the halo can yield delayed emission, of which the profile also shows typical two-peak structure as that from locally thermalized photons. Possible applications of these results are addressed.