Miracle-dz/UniFAR-FTUs huggingface dataset:
Constraint on ion–neutral drift velocity in the Class 0 protostar B335 from ALMA observations

Aims. Ambipolar diffusion can cause a velocity drift between ions and neutrals. This is one of the non-ideal magnetohydrodynamics (MHD) effects proposed to enable the formation of large-scale Keplerian disks with sizes of tens of au. To observationally study ambipolar diffusion in collapsing protostellar envelopes, we compare here gas kinematics traced by ionized and neutral molecular lines and discuss the implication on ambipolar diffusion. Methods. We analyzed the data of the H13CO+ (3–2) and C18O (2–1) emission in the Class 0 protostar B335 obtained with our ALMA observations. We constructed kinematical models to fit the velocity structures observed in the H13CO+ and C18O emission and to measure the infalling velocities of the ionized and neutral gas on a 100 au scale in B335. Results. A central compact (~1′′–2′′) component that is elongated perpendicular to the outflow direction and exhibits a clear velocity gradient along the outflow direction is observed in both lines and most likely traces the infalling flattened envelope. With our kinematical models, the infalling velocities in the H13CO+ and C18O emission are both measured to be 0.85 ± 0.2 km s−1 at a radius of 100 au, suggesting that the velocity drift between the ionized and neutral gas is at most 0.3 km s−1 at a radius of 100 au in B335. Conclusions. The Hall parameter for H13CO+ is estimated to be ≫1 on a 100 au scale in B335, so that H13CO+ is expected to be attached to the magnetic field. Our non-detection or upper limit of the velocity drift between the ionized and neutral gas could suggest that the magnetic field remains rather well coupled to the bulk neutral material on a 100 au scale in this source, and that any significant field-matter decoupling, if present, likely occurs only on a smaller scale, leading to an accumulation of magnetic flux and thus efficient magnetic braking in the inner envelope. This result is consistent with the expectation from the MHD simulations with a typical ambipolar diffusivity and those without ambipolar diffusion. On the other hand, the high ambipolar drift velocity of 0.5–1.0 km s−1 on a 100 au scale predicted in the MHD simulations with an enhanced ambipolar diffusivity by removing small dust grains, where the minimum grain size is 0.1 μm, is not detected in our observations. However, because of our limited angular resolution, we cannot rule out a significant ambipolar drift only in the midplane of the infalling envelope. Future observations with higher angular resolutions (~0. ′′1) are needed to examine this possibility and ambipolar diffusion on a smaller scale.
Evolutionary constraints on the long-period subdwarf B binary PG 1018–047

We have revisited the sdB+K-star long-period binary PG 1018–047 based on 20 new high-resolution Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph spectra that provided regular coverage over a period of more than 26 m. We refine the period and establish that the orbit is significantly eccentric (P = 751.6 ± 1.9 d and e = 0.049 ± 0.008). A simultaneous fit derived from the narrow metal lines visible in the spectrum of the sdB star and the metal lines in the red part of the spectrum that originate from the companion provides the mass ratio, MMS/MsdB = 1.52 ± 0.04, for the system. From an NLTE model atmosphere analysis of the combined spectra, we find Teff = 29900 ± 330 K, log g = 5.65 ± 0.06 dex and log(nHe/nH) = –3.98 ± 0.16 dex for the primary, consistent with a B-type hot subdwarf star. The spectral contribution of the companion is consistent with a K5V-type star. With the companion having a mass of only ∼ 0.7 M⊙, this system lies close to the boundary below which stable Roche lobe overflow (RLOF) cannot be supported. To model the evolution of such a system, we have extended earlier MESA models towards lower companion masses. We find that both phase-dependent mass loss during RLOF, when 30 to 40 per cent of the available mass is lost through the outer Lagrange point and phase-dependent mass loss during RLOF in combination with a circumbinary disc of maximum MCB = 0.001 M⊙ could have formed the PG 1018–047 binary system.
Upper bounds on the superfluid stiffness and superconducting $T_c$: Applications to twisted-bilayer graphene and ultra-cold Fermi gases

Understanding the material parameters that control the superconducting (SC) transition temperature Tc is a problem of fundamental importance. In many novel superconductors, phase fluctuations of the SC order parameter determine Tc, rather than the mean field collapse of the amplitude due to pair breaking. We derive rigorous upper bounds on the superfluid phase stiffness Ds valid in any dimension. This in turn leads to an upper bound on Tc in 2D, which holds irrespective of mechanism, strength of pairing interaction, or order-parameter symmetry. These bounds lead to stringent constraints for the strongly correlated regime of low-density and narrow-band systems. We show that kBTc ≤ EF /8 across the 2D BCS-BEC crossover in ultra-cold Fermi gases. For magic-angle twisted bilayer graphene (MATBG), the band structure constrains the maximum possible Tc to be close to the experimentally observed value, demonstrating that MA-TBG is in a phase-fluctuation dominated regime. Finally, we discuss the question of deriving rigorous upper bounds on Tc in 3D.
Finite-Size Scaling for Nonlinear Rheology of Fluids Confined in a Periodic Box

We perform an extensive molecular dynamics simulation in order to elucidate the rheological properties of fluids confined in a small periodic box. We find that the shear viscosity η decreases as \(\dot{\gamma}^{-2/3}\) with the shear rate \(\dot{\gamma}\) when the system size L is relatively small, while η is independent of \(\dot{\gamma}\) when the system size is sufficiently large. By performing a systematic finite-size scaling analysis, we demonstrate that this system size dependence can be observed when the system size becomes comparable to the length scale that characterizes the cooperative motion of particles.
Quantum Mechanical versus Stochastic Processes in Path Integration

By using path integrals, the stochastic process associated to the time evolution of the quantum probability density is formally rewritten in terms of a stochastic differential equation, given by Newton's equation of motion with an additional multiplicative stochastic force. However, the term playing the role of the stochastic force is defined by a non-positive-definite probability functional, providing a clear example of the negative (or "extended") probabilities characteristic of quantum mechanics.
Detox Loss: Fairness Constraints for Learning With Imbalanced Data

Recent studies have highlighted a major caveat in several popular deep learning based face recognition algorithms. Despite their high accuracy, they have shown to exhibit biased behavior by achieving sub-par performance on images belonging to different sub-groups. Such behavior can often lead to unfair predictions, thus presenting a need to develop fairer models with unprejudiced behavior. This research proposes Detox loss, a novel bias invariant feature learning loss function for learning unbiased models. The proposed loss can be used to: (i) learn fairer deep learning classifiers, and (ii) mitigate bias from existing pre-trained networks, especially in the challenging constraint of imbalanced training data with respect to a protected attribute. Conceptually, the Detox loss enforces that the learned features are distinguished based on the task label only, while eliminating any distinction based on the biasing-attribute. This is achieved by incorporating three fairness constraints while training with the traditional classification loss: (i) proposed Exclusion loss, (ii) proposed Inclusion loss, and (iii) proposed Feature-distillation loss. The efficacy of the Detox loss is demonstrated on two facial analysis tasks: (i) age-group prediction and (ii) gender prediction, under the protected attribute of ethnicity for learning fairer models and de-biasing existing models, with varying imbalanced training data distributions. Across two different protocols, three setups, and two tasks, the Detox loss obtains state of the art performance without the need of multi-labeled training data. For example, on the challenging Pilot Parliaments Benchmark (PPB) dataset, the Detox loss obtains a balanced accuracy and $F_{1}$ score of 96.1% and 96.6%, as compared to the state-of-the-art performance of 94.1% and 93.6%, respectively.
Evolution in the Colors of Lyman Break Galaxies from z ~ 4 to z ~ 3

The integrated colors of distant galaxies provide a means for interpreting the properties of their stellar content. Here we use rest-frame UV-to-optical colors to constrain the spectral energy distributions and stellar populations of color-selected, B-dropout galaxies at z ~ 4 in the Great Observatories Origins Deep Survey (GOODS). We combine the Advanced Camera for Surveys data with ground-based near-infrared images, which extend the coverage of galaxies at z ~ 4 to the rest-frame B band. We observe a color-magnitude trend in the rest-frame m(UV)-B versus B diagram for the z ~ 4 galaxies that has a fairly well-defined "blue envelope," and is strikingly similar to that of color-selected, U-dropout galaxies at z ~ 3. We also find that although the co-moving luminosity density at rest-frame UV wavelengths (1600 Å) is roughly comparable at z ~ 3 and ~4, the luminosity density at rest-frame optical wavelengths increases by about one-third from z ~ 4 to ~3. Although the star formation histories of individual galaxies may involve complex and stochastic events, the evolution in the global luminosity density of the UV-bright galaxy population corresponds to an average star formation history with a star formation rate that is constant or increasing over these redshifts. This suggests that the evolution in the luminosity density corresponds to an increase in the stellar mass density of ≳33%.
Quantum Dynamics of a Two-level System Near a Gold Nanoparticle

The ability to prepare desired states without allowing time for the atomic system to spontaneously decay to the ground state is limited by the fact that Hamiltonian controls cannot affect the purity of the state in question. In this paper, we discuss how a continuous off-resonant electromagnetic wave can be used to prepare a desired final quantum state. With the aid of plasmonic surface-enhancement, by placing a two-level atomic system near a gold nanoparticle, preparation is accomplished in a reduced period of time and with lower electric field intensity while the system purity is improved when compared to an isolated system.
Wave-front solution behaviour for continuous neural networks with lateral inhibition

In this paper we discuss the shape of travelling wave-front solutions to a model for a single continuous layer of nerve cells originally introduced by Amari (1977, Dynamics of pattern formation in lateral inhibition-type neural fields. Biol. Cybem., 27, 77-87). The neural field is homogeneous and isotropic, and the connection function is one of lateral inhibition type, meaning that nearby connecting cells have an excitatory influence, while more spatially distant cells impose an inhibitory influence. We give results on the shape of the wave-front solutions, which are non-monotone and exhibit different shapes depending on the size of a threshold parameter. For a layer of excitatory cells indirectly inhibited by a second layer of cells, we derive results on the qualitative behaviour of wave-fronts for changes in parameters representing the inhibitory firing threshold and the time-scale of the inhibition process. This study shows how intrinsic cell and network parameter can interact to shape global response properties.
Evaluating Image Classification Deep Convolutional Neural Network Architectures for Remaining Useful Life Estimation of Turbofan Engines

Accurate estimation of the remaining useful life (RUL) is a key component of condition-based maintenance (CBM) and prognosis and health management (PHM). Data-based models for the estimation of RUL are of particular interest because expert knowledge of systems is not always available, and physical modeling is often not feasible. Additionally, using data-based models, which make decisions based on raw sensor data, allow features to be learned instead of manually determined. In this work, deep convolutional neural network (CNN) architectures are investigated for their ability to estimate the RUL of turbofan engines. To improve the accuracy of the models, CNN architectures, which have proven successful in image classification, are implemented and tested. Specifically, the blocks used in the Visual Geometry Group (VGG) architecture, inception modules used in the GoogLeNet architecture, and residual blocks used in the ResNet architecture are incorporated. To account for varying flight lengths, the input to the models is a window of time series data collected from the engine under test. Window locations at the climb, cruise, and descent stages are considered. To further improve the RUL estimations, multiple overlapping windows at each location are used. This increases the amount of training data available and is found to increase the accuracy of the resulting RUL estimations by averaging the estimates from all overlapping segments. The model is trained and tested using the new Commercial Modular Aero-Propulsion System Simulation (N-CMAPSS) data set, and high prognosis accuracy was achieved. This work expands on the model developed and used in the 2021 PHM Society Data Challenge, which received second place.
The effect of making one plus one greater than two: endoscopic double snare resection of an esophageal leiomyoma

Endoscopic submucosal dissection (ESD) is established as the standard en bloc resection method for superficial esophageal tumor, including leiomyoma [1, 2]. However, it comes with the drawback of significant technical requirements, long procedure times, and potential adverse complications [3]. Because of this, we established a novel double snare resection (DSR) technique to effectively accomplish en bloc resection of a small esophageal leiomyoma (▶Video 1).
A Differential Flip-Flop With Static Contention-Free Characteristics in 28 nm for Low-Voltage, Low-Power Applications

A static contention-free differential flip-flop (SCDFF) is presented in 28-nm CMOS for low-voltage and low-power applications. The SCDFF offers fully static and contention-free operation without redundant internal clock transitions with footed differential latches and the same area as a conventional transmission-gate flip-flop (TGFF). The fully static and contention-free operation allows high variation tolerance at a low supply voltage regime, achieving wide-range voltage scalability (1–0.3 V). The measurement results with a test chip fabricated in 28-nm CMOS technology show that power consumption is reduced by 64%/56% with a 0%/10% activity ratio at 1 V compared to that of a TGFF. All 100 dies from five process corners were functional with supply voltage as low as 0.28 V.
Be-9 abundances in population II stars - Implications for light element nucleosynthesis

Upper limits on the Be-9 abundances in four metal-deficient dwarfs were obtained by applying the spectrum synthesis technique to high-resolution spectra at 3130 A. The abundance of Be-9 is seen to track the iron deficiency rather than maintain a nearly uniform abundance as is seen for the neighboring light element, Li-7. The deficiency of Be-9 permits the cosmic-ray spallation contribution to the Li-7 abundance of HD 140283 to be stated as less than 1 percent. The very low abundance of Be-9 can be used to constrain recent nonuniform density models for the big bang, which predict significant primordial abundances for this element. 35 refs.
Mathematical Model of Water Absorption in Arrowroot Starch-Chitosan Based Bioplastic

Expansion of the size of the weight of bioplastics often occurs in daily use. This phenomenon happens because the material from bioplastics can absorb significant amounts of water. This process can lead to accumulation of swelling degree. Therefore, a mathematical model is needed to quantify this mechanism to predict the dynamics of changes in the weight of bioplastics with respet to time while contact with water to help practitioners during application design for the use of bioplastics. This study aims to build a mathematical model derived from the mass sense validated by experimental data through curve fitting. The experiment was conducted by observing the rate of change in the mass of bioplastic made from starch and chitosan by measuring the change in mass concerning time immersed in water under atmospheric conditions. The immersion time was varied between 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40,50, and 60 minutes. As a result, it can be concluded that starch-chitosan-based biofilms can absorb water up to ±10.9174 gr-water/gr-bioplastic, and also this phenomenon can be quantified by a mathematical equation that derived from mass balance with an average percent error of 1.13% and R-squared coefficient of 0.9981.
Lipid Serum Profiling of Boar-Tainted and Untainted Pigs Using GC×GC–TOFMS: An Exploratory Study

Mass spectrometry (MS)-based techniques, including liquid chromatography coupling, shotgun lipidomics, MS imaging, and ion mobility, are widely used to analyze lipids. However, with enhanced separation capacity and an optimized chemical derivatization approach, comprehensive two-dimensional gas chromatography (GC×GC) can be a powerful tool to investigate some groups of small lipids in the framework of lipidomics. This study describes the optimization of a dedicated two-stage derivatization and extraction process to analyze different saturated and unsaturated fatty acids in plasma by two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC–TOFMS) using a full factorial design. The optimized condition has a composite desirability of 0.9159. This optimized sample preparation and chromatographic condition were implemented to differentiate between positive (BT) and negative (UT) boar-tainted pigs based on fatty acid profiling in pig serum using GC×GC–TOFMS. A chemometric screening, including unsupervised (PCA, HCA) and supervised analysis (PLS–DA), as well as univariate analysis (volcano plot), was performed. The results suggested that the concentration of PUFA ω-6 and cholesterol derivatives were significantly increased in BT pigs, whereas SFA and PUFA ω-3 concentrations were increased in UT pigs. The metabolic pathway and quantitative enrichment analysis suggest the significant involvement of linolenic acid metabolism.
Evanescent Field Functional Cu3-xP Nanoparticles as Effective Saturable Absorbers with high Repeatability for Femtosecond Soliton Pulse generation.

Recently, a new emerging field about heavily-doped colloidal plasmonic nanocrystals (NCs) has attracted great attention due to their lower and expediently adjustable free carrier densities, lower and tunable LSPR band in the spectral range from NIR to MIR and higher optical nonlinearity. These new kinds of plasmonic materials will show huge potential and opportunities for nonlinear optical applications, such as ultrafast switching, nonlinear sensing and pulse laser generation. In this work, we demonstrate that high-quality mode-locking and Q-switching pulses at 1560 nm can both be generated by using controllable concentration of Cu3-xP NCs solution and fabricating evanescently interacted saturable absorbers. Furthermore, the plasmonic NCs material has good reproduction for fabricating SA devices and promising potential for large-scale industrial production. Our results may attract great attention for further investigations of heavily-doped plasmonic NCs as next generation, cheap and solution-processed element for fascinating applications in optoelectronic devices.
FLUCTUATING INTERFACES, SURFACE TENSION, AND CAPILLARY WAVES: AN INTRODUCTION

We present an introduction to modern theories of interfacial fluctuations and the associated interfacial parameters: surface tension and surface stiffness, as well as their interpretation within the capillary wave model. Transfer matrix spectrum properties due to fluctuation of an interface in a long-cylinder geometry are reviewed. The roughening transition and properties of rigid interfaces below the roughening temperature in 3d lattice models are surveyed with emphasis on differences in fluctuations and transfer matrix spectral properties of rigid vs. rough interfaces.
Primordial Black Holes - Recent Developments

Recent developments in the study of primordial black holes (PBHs) will be reviewed, with particular emphasis on their formation and evaporation. PBHs could provide a unique probe of the early Universe, gravitational collapse, high energy physics and quantum gravity. Indeed their study may place interesting constraints on the physics relevant to these areas even if they never formed. In the "early Universe" context, particularly useful constraints can be placed on inflationary scenarios, especially if evaporating PBHs leave stable Planck-mass relicts. In the "gravitational collapse" context, the existence of PBHs could provide a unique test of the sort of critical phenomena discovered in recent numerical calculations. In the "high energy physics" context, information may come from gamma-ray bursts (if a subset of these are generated by PBH explosions) or from cosmic rays (if some of these derive from evaporating PBHs). In the "quantum gravity" context, the formation and evaporation of small black holes could lead to observable signatures in cosmic ray events and accelerator experiments, providing there are extra dimensions and providing the quantum gravity scale is around a TeV.
Calibration and irradiation study of the BGO background monitor for the BEAST II experiment

Beam commissioning of the SuperKEKB collider began in 2016. The Beam Exorcism for A STable experiment II (BEAST II) project is particularly designed to measure the beam backgrounds around the interaction point of the SuperKEKB collider for the Belle II experiment. We develop a system using bismuth germanium oxide (BGO) crystals with optical fibers connecting to a multianode photomultiplier tube (MAPMT) and a field-programmable gate array (FPGA) embedded readout board for monitoring the real-time beam backgrounds in BEAST II. The overall radiation sensitivity of this system is estimated to be (2.20±0.26)×10−12 Gy/ADU (analog-to-digital unit) with the standard 10 m fibers for transmission and the MAPMT operating at 700 V. Our γ-ray irradiation study of the BGO system shows that the exposure of BGO crystals to 60Co γ-ray doses of 1 krad has led to immediate light output reductions of 25–40%, and the light outputs further drop by 30–45% after the crystals receive doses of 2–4 krad. Our findings agree with those of the previous studies on the radiation hard (RH) BGO crystals grown by the low thermal gradient Czochralski (LTG Cz) technology. The absolute dose from the BGO system is also consistent with the simulation, and is estimated to be about 1.18 times the equivalent dose. These results prove that the BGO system is able to monitor the background dose rate in real time under extreme high radiation conditions. This study concludes that the BGO system is reliable for the beam background study in BEAST II.