Miracle-dz/UniFAR-FTUs huggingface dataset:
NEW EXTREME TRANS-NEPTUNIAN OBJECTS: TOWARD A SUPER-EARTH IN THE OUTER SOLAR SYSTEM

We are performing a wide and deep survey for extreme distant solar system objects. Our goal is to understand the high-perihelion objects Sedna and 2012 VP113 and determine if an unknown massive planet exists in the outer solar system. The discovery of new extreme objects from our survey of some 1080 square degrees of sky to over 24th magnitude in the r-band are reported. Two of the new objects, 2014 SR349 and 2013 FT28, are extreme detached trans-Neptunian objects, which have semimajor axes greater than 150 au and perihelia well beyond Neptune (q > 40 au). Both new objects have orbits with arguments of perihelia within the range of the clustering of this angle seen in the other known extreme objects. One of these objects, 2014 SR349, has a longitude of perihelion similar to the other extreme objects, but 2013 FT28 is about 180° away or anti-aligned in its longitude of perihelion. We also discovered the first outer Oort Cloud object with a perihelion beyond Neptune, 2014 FE72. We discuss these and other interesting objects discovered in our ongoing survey. All the high semimajor axis (a > 150 au) and high-perihelion (q > 35 au) bodies follow the previously identified argument of perihelion clustering as first reported and explained as being from an unknown massive planet in 2014 by Trujillo & Sheppard, which some have called Planet X or Planet Nine. With the discovery of 2013 FT28 on the opposite side of the sky, we now report that the argument of perihelion is significantly correlated with the longitude of perihelion and orbit pole angles for extreme objects and find there are two distinct extreme clusterings anti-aligned with each other. This previously unnoticed correlation is further evidence of an unknown massive planet on a distant eccentric inclined orbit, as extreme eccentric objects with perihelia on opposite sides of the sky (180° longitude of perihelion differences) would approach the inclined planet at opposite points in their orbits, thus making the extreme objects prefer to stay away from opposite ecliptic latitudes to avoid the planet (i.e., opposite argument of perihelia or orbit pole angles).
A Local Positive Feedback Loop-Reused Technique for Enhancing Performance of Folded Cascode Amplifier

A current-reused folded cascode operational transconductance amplifier (OTA) using a local positive feedback (LPFB) technique has been proposed in previous literature, which does not achieve maximum unity gain-bandwidth (GBW). Besides, the stability of LPFB in the LPFB OTA is limited by local common mode feedback (LCMFB) resistors. Based on the analysis, a local positive feedback loop-reused (LPFBR) technique is proposed to improve the performance of conventional LPFB OTA. For a fair comparison, both conventional and proposed OTAs working at saturation region are designed and simulated in SMIC 0.18 μm process. The simulated results demonstrate that the proposed LPFBR OTA has almost 10.5 times the bandwidth and maintains stability compared to that of the conventional LPFB OTA under the condition that LCMFB resistors are increased by a factor of 10.
Pushing the limits: detecting H2 emission from faint bipolar planetary nebulae in the IPHAS sample

We have obtained deep narrowband images in the near-infrared H2 (2.122 microns) emission line for a sample of 15 faint Isaac Newton Telescope Photometric Halpha Survey (IPHAS) bipolar planetary nebulae (PNe) to search for molecular material. H2 emission is found in most of them (14 out of 15), mostly associated with rings at their equatorial regions and with their bipolar lobes. These detections add to the high occurrence of H2 emission among bipolar PNe reported in previous works, resulting from the large reservoir of molecular material in these sources and the suitable excitation conditions for H2 emission. The correlation between detailed bipolar morphology and H2 luminosity is also confirmed: bipolar PNe with broad equatorial rings (R-BPNe) have almost no continuum emission, are H2 brighter and have larger H2/Brgamma line ratio than bipolar PNe with pinched equatorial waists (W-BPNe). The origin of this dichotomy is unclear. The larger size and age of R-BPNe are consistent with shock excitation of H2, whereas ultraviolet pumping is most likely the excitation mechanism in the smaller and younger W-BPNe, which would explain their lower H2 luminosity. Although both types of bipolar PNe seem to proceed from the same progenitor population, this does not imply that R-BPNe descend from W-BPNe. Otherwise, we note that some of the H2-weak bipolar PNe harbor post-common envelope binary systems and symbiotic stars. Finally, we suggest that the long-living H2 emission from R-BPNe arises from a discrete distribution of compact knots embedded within the ionized gas at the equatorial region.
Histological and Molecular Evidence of the Positive Performance of Glycerol-Plasticized Chitosan-Alginate Membranes on Skin Lesions of Hyperglycemic Mice

The purpose of this study was to investigate tissue repair of excisional wounds in hyperglycemic animals treated with chitosan-alginate membranes (CAM) produced in the presence of glycerol. 8-week C57B1 male mice were divided into normoglycemic animals with a 0.9% saline solution topical treatment (CTSF); hyperglycemic animals with 0.9% saline solution topical treatment (DMSF) and hyperglycemic animals with glycerol-plasticized chitosan-alginate membrane topical treatment (DMCAM). On post-wound day three, the DMCAM group presented a lower number of leukocytes, mature mastocytes, a higher number of vessels (p < 0.05), and active mastocytes (p < 0.05) when compared to the CTSF and DMSF groups. There were no differences regarding the distribution, deposition, organization, and thickness of collagen fibers. On day 7 there were no differences in the analysis of fibroblasts, mastocytes, and TGF−β1 and VEGF expressions among the groups. Regarding collagen fibers, the DMCAM group presented slight red-orange birefringence when compared to the CTSF and DMSF groups. On day 14 there was a slight concentration of thinner elastic fibers for the DMCAM group, with a greater reorganization of papillary skin and improved red-orange birefringence collagen fibers, as well as net-shaped orientation, similar to intact skin. In addition, improved elastic fiber organization distributed in the entire neo-dermis and a larger presence of elaunin fibers were observed, in a similar pattern found in the intact skin. The use of CAM in cutaneous lesions boosted tissue repair since there was a smaller number of inflammatory cells and mastocytes, and an improvement in collagen deposition and collagen fibers. These results demonstrate the high potential of plasticized chitosan-alginate membrane for skin wound dressing of hyperglycemic patients.
Network analysis of the COSMOS galaxy field

The galaxy data provided by COSMOS survey for 1 by 1 degree field of sky are analysed by methods of complex networks. Three galaxy samples (slices) with redshifts ranging within intervals 0.88-0.91, 0.91-0.94 and 0.94-0.97 are studied as two-dimensional projections for the spatial distributions of galaxies. We construct networks and calculate network measures for each sample, in order to analyse the network similarity of different samples, distinguish various topological environments, and find associations between galaxy properties (colour index and stellar mass) and their topological environments. Results indicate a high level of similarity between geometry and topology for different galaxy samples and no clear evidence of evolutionary trends in network measures. The distribution of local clustering coefficient C manifests three modes which allow for discrimination between stand-alone singlets and dumbbells (0 <= C <= 0.1), intermediately (0 < C < 0.9) and clique (0.9 <= C <= 1) like galaxies. Analysing astrophysical properties of galaxies (colour index and stellar masses), we show that distributions are similar in all slices, however weak evolutionary trends can also be seen across redshift slices. To specify different topological environments we have extracted selections of galaxies from each sample according to different modes of C distribution. We have found statistically significant associations between evolutionary parameters of galaxies and selections of C: the distribution of stellar mass for galaxies with interim C differ from the corresponding distributions for stand-alone and clique galaxies, and this difference holds for all redshift slices. The colour index realises somewhat different behaviour.
Broadband microwave sub-second pulsations in an expanding coronal loop of the 2011 August 10 flare

We studied the characteristic physical properties and behavior of broadband microwave sub-second pulsations observed in an expanding coronal loop during the GOES C2.4 solar flare on 2011 August 10. We found sub-second pulsations and other different burst groups in the complex radio spectrum. The broadband (bandwidth about 1 GHz) sub-second pulsations (temporal period range 0.07-1.49 s, no characteristic dominant period) lasted 70 s in the frequency range 4-7 GHz. These pulsations were not correlated at their individual frequencies, had no measurable frequency drift, and zero polarization. In these pulsations, we found the signatures of fast sausage magnetoacoustic waves with the characteristic periods of 0.7 and 2 s. The other radio bursts showed their characteristic frequency drifts in the range of -262-520 MHz/s. They helped us to derive average values of 20-80 G for the coronal magnetic field strength in the place of radio emission. It was revealed that the microwave event belongs to an expanding coronal loop with twisted sub-structures observed in the 131, 94, and 193 A SDO/AIA channels. Their slit-time diagrams were compared with the location of the radio source at 5.7 GHz to realize that the EUV intensity of the expanding loop increased just before the radio source triggering. We reveal two EUV bidirectional flows that are linked with the start time of the loop expansion. Their positions were close to the radio source and propagated with velocities within a range of 30-117 km/s. We demonstrate that periodic regime of the electron acceleration in a model of the quasi-periodic magnetic reconnection might be able to explain physical properties and behavior of the sub-second pulsations. The depolarization process of the microwave emission might be caused by a plasma turbulence in the radio source. Finally, the observed EUV flows might be linked with reconnection outflows.
Dorsal Hand Vein Identification using Transfer Learning from AlexNet

Dorsal hand vein pattern is a highly secured biometric system that has been used in many applications due to its non-contact attributes. Prior studies focused on investigation of different deep networks for hand vein classification task using different training parameters. It is the aim of this study to propose the use of systematic fine-tuning system for identifying the best parameters value for enhanced model learning efficiency. In this study, pre-trained AlexNet was trained using Bosphorus hand vein database for identification of 100 users. The experiments were carried out using original images, and preprocessed (cropped) images for comparison. The testing accuracies of these datasets were compared following tuning of training parameters, namely trainingand testing split ratio, number of epochs, mini-batch size and initial learning rate. It was observed that the testing accuracy of the model trained using cropped images is higher than that using the original images. The model from preprocessed dataset shows a good testing accuracy of 96 % using a split ratio of 90:10, epoch 50, mini-batch-size of 10 and an initial learning rate of 0.0001. The performance of our trained model is more superior than many reported results in the field. In future, the performance of this classification system may be further enhanced with automatic search of parameters for improved model training efficiency.
Rethinking English as Medium of Instruction Policy in Multilingual Classrooms

This paper reports the results of a study that unpacked teachers’ experiences and challenges adopting EMI policy in the public schools’ multilingual classrooms. Building on a phenomenological design, we selected two primary level teachers purposively and collected data through in-depth interviews. Drawing upon the thematic analysis and interpretation of the data, the study revealed that teachers perceived EMI as a tool for achieving English language proficiency for the students and a means for the public schools to compete with their private counterparts. Contrarily, EMI in the public school’s multilingual classrooms was found to be practised just as slogan and insufficient for effective students’ participation in classroom learning. Since EMI leads multilingual learners towards monolingual direction, it has posed problems to both the teachers and students due to the low English language proficiency. The study implies that the EMI policy in the lower grades of public schools should be implemented considering the linguistic and cultural milieus of the students.
Quantum corrals and quantum mirages on the surface of a topological insulator

We study quantum corrals on the surface of a topological insulator (TI). Different resonance states induced by nonmagnetic (NM), antiferromagnetic (AFM), and ferromagnetic (FM) corrals are found. Intriguingly, the spin is clearly energy-resolved in a FM corral, which can be effectively used to operate surface carrier spins of TI. We also show that an observable quantum mirage of a magnetic impurity can be projected from the occupied into the empty focus of a FM elliptic corral, while in NM and AFM corrals the mirage signal becomes negligibly weak. In addition, the modulation of the interaction between two magnetic impurities in the quantum corrals is demonstrated. These prominent effects may be measured by spin-polarized STM experiments.
Potential Role of TRPV4 in Stretch-Induced Ghrelin Secretion and Obesity

Obesity is an important health problem, which can be prevented through appetite control. Ghrelin is an appetite-stimulating hormone considered to promote obesity. Thus, we examined whether gastric stretching affects ghrelin secretion. We investigated the role of transient receptor potential vanilloid 4 (TRPV4) in gastric glands in the regulation of ghrelin secretion. TRPV4 immunostaining was performed in tissue samples from 57 patients who underwent gastrectomy. TRPV4 expression was compared between patients with (body mass index (BMI) ≥ 30) and without (BMI <30) obesity. For in vitro experiments, we used MGN3-1 cells, a ghrelin-producing cell line derived from mice. To investigate the bioactivity of TRPV4, MGN3-1 cells were treated with TRPV4 agonists and antagonists, and changes in intracellular Ca2+ concentration were confirmed. The concentration of ghrelin in the cell supernatant was measured using the ELISA with and without 120% stretch stimulation. TRPV4 expression was significantly higher in patients with obesity than in those without at all sites, except the fornix. Immunostaining confirmed the expression of TRPV4 in MGN3-1 cells. TRPV4 agonist administration increased intracellular Ca2+ concentration and ghrelin secretion in MGN3-1 cells, whereas the administration of the agonist combined with the antagonist decreased intracellular Ca2+ concentration and ghrelin secretion. Ghrelin secretion significantly increased in response to a 120% stretch in MGN3-1 cells. However, secretion was not increased by stretch when cells were treated with a TRPV4 antagonist. TRPV4 regulates ghrelin secretion in response to stretch in the stomach, which may affect body weight.
Precise CCD positions of Himalia using Gaia DR1 in 2015-2016

In order to obtain high precision CCD positions of Himalia, the sixth Jovian satellite, a total of 598 CCD observations have been obtained during the years 2015-2016. The observations were made by using the 2.4 m and 1 m telescopes administered by Yunnan Observatories over 27 nights. Several factors which would influence the positional precision of Himalia were analyzed, including the reference star catalogue used, the geometric distortion and the phase effect. By taking advantage of its unprecedented positional precision, the recently released catalogue Gaia DR1 was chosen to match reference stars in the CCD frames of both Himalia and open clusters which were observed for deriving the geometric distortion. The latest version of SOFA library was used to calculate the positions of reference stars. The theoretical positions of Himalia were retrieved from the Jet Propulsion Laboratory Horizons System which includes the satellite ephemeris JUP300, while the positions of Jupiter were based on the planetary ephemeris DE431. Our results showed that the means of observed minus computed (O-C) residuals are 0.071 and -0.001 arcsec in right ascension and declination, respectively. Their standard deviations are estimated at about 0.03 arcsec in each direction.
Evolution of Supernova Remnants Near the Galactic Center

Supernovae near the Galactic center (GC) evolve differently from regular Galactic supernovae. This is mainly due to the environment into which the supernova remnants (SNRs) propagate. SNRs near the GC propagate into a wind swept environment with a velocity directed away from the GC, and a graded density profile. This causes these SNRs to be non-spherical, and to evolve faster than their Galactic counterparts. We develop an analytic theory for the evolution of explosions within a stellar wind, and verify it using a hydrodynamic code. We show that such explosions can evolve in one of three possible morphologies. Using these results we discuss the association between the two SNRs (SGR East and SGR A’s bipolar radio/X-ray lobes) and the two neutron stars (the Cannonball and SGR J1745-2900) near the GC. We show that, given the morphologies of the SNR and positions of the neutron stars, the only possible association is between SGR A’s bipolar radio/X-ray lobes and SGR J1745-2900. If a compact object was created in the explosion of SGR East, it remains undetected, and the SNR of the supernova that created the Cannonball has already disappeared.
Time-dependent quantum transport and power-law decay of the transient current in a nano-relay and nano-oscillator

Time-dependent nonequilibrium Green’s functions are used to study electron transport properties in a device consisting of two linear chain leads and a time-dependent interlead coupling that is switched on non-adiabatically. We derive a numerically exact expression for the particle current and examine its characteristics as it evolves in time from the transient regime to the long-time steady-state regime. We find that just after switch-on, the current initially overshoots the expected long-time steady-state value, oscillates and decays as a power law, and eventually settles to a steady-state value consistent with the value calculated using the Landauer formula. The power-law parameters depend on the values of the applied bias voltage, the strength of the couplings, and the speed of the switch-on. In particular, the oscillating transient current decays away longer for lower bias voltages. Furthermore, the power-law decay nature of the current suggests an equivalent series resistor-inductor-capacitor circuit.
Matched-filter study and energy budget suggest no detectable gravitational-wave ‘extended emission’ from GW170817

Van Putten & Della Valle (2018) have reported a possible detection of gravitational-wave 'extended emission' from a neutron star remnant of GW170817. Starting from the time-frequency evolution and total emitted energy of their reported candidate, we show that such an emission is not compatible with the current understanding of neutron stars. We explore the additional required physical assumptions to make a full waveform model, for example, taking the optimistic emission from a spining-down neutron star with fixed quadrupolar deformation, and study whether even an ideal single-template matched-filter analysis could detect an ideal, fully phase-coherent signal. We find that even in the most optimistic case an increase in energy and extreme parameters would be required for a confident detection with LIGO sensitivity as of 2018-08-17. The argument also holds for other waveform models following a similar time-frequency track and overall energy budget. Single-template matched filtering on the LIGO data around GW170817, and on data with added simulated signals, verifies the expected sensitivity scaling and the overall statistical expectation.
The deepestChandraX-ray study of the plerionic supernova remnant G21.5−0.9

G21.5-0.9 is a plerionic supernova remnant (SNR) used as a calibration target for the Chandra X-ray telescope. The first observations found an extended halo surrounding the bright central pulsar wind nebula (PWN). A 2005 study discovered that this halo is limb-brightened and suggested the halo to be the missing SNR shell. In 2010 the spectrum of the limb-brightened shell was found to be dominated by non-thermal X-rays. In this study, we combine 15 years of Chandra observations comprising over 1~Msec of exposure time (796.1~ks with the Advanced CCD Imaging Spectrometer (ACIS) and 306.1~ks with the High Resolution Camera (HRC)) to provide the deepest-to-date imaging and spectroscopic study. The emission from the limb is primarily non-thermal and is described by a power-law model with a photon index $\Gamma = 2.22 \, (2.04-2.34)$, plus a weak thermal component characterized by a temperature $kT = 0.37\, (0.20-0.64)$ keV and a low ionization timescale of $n_{e}t < 2.95 \times 10^{10}$ cm$^{-3}$s. The northern knot located in the halo is best fitted with a two-component power-law + non-equilibrium ionization thermal model characterized by a temperature of 0.14 keV and an enhanced abundance of silicon, confirming its nature as ejecta. We revisit the spatially resolved spectral study of the PWN and find that its radial spectral profile can be explained by diffusion models. The best fit diffusion coefficient is $D \sim 2.1\times 10^{27}\rm cm^2/s$ assuming a magnetic field $B =130 \mu G$, which is consistent with recent 3D MHD simulation results.
XMM-Newton observations of the X-ray soft polar QS Telescopii

Context. On the basis of XMM-Newton observations, we investigate the energy balance of selected magnetic cataclysmic variables, which have shown an extreme soft-to-hard X-ray flux ratio in the ROSAT All-Sky Survey. Aims. We intend to establish the X-ray properties of the system components, their flux contributions, and the accretion geometry of the X-ray soft polar QS Tel. In the context of high-resolution X-ray analyses of magnetic cataclysmic variables, this study will contribute to better understanding the accretion processes on magnetic white dwarfs. Methods. During an intermediate high state of accretion of QS Tel, we have obtained 20 ks of XMM-Newton data, corresponding to more than two orbital periods, accompanied by simultaneous optical photometry and phase-resolved spectroscopy. We analyze the multi-wavelength spectra and light curves and compare them to former high- and low-state observations. Results. Soft emission at energies below 2 keV dominates the X-ray light curves. The complex double-peaked maxima are disrupted by a sharp dip in the very soft energy range (0.1-0.5 keV), where the count rate abruptly drops to zero. The EPIC spectra are described by a minimally absorbed black body at 20 eV and two partially absorbed MEKAL plasma models with temperatures around 0.2 and 3 keV. The black-body-like component arises from one mainly active, soft X-ray bright accretion region nearly facing the mass donor. Parts of the plasma emission might be attributed to the second, virtually inactive pole. High soft-to-hard X-ray flux ratios and hardness ratios demonstrate that the high-energy emission of QS Tel is substantially dominated by its X-ray soft component.