Miracle-dz/UniFAR-FTUs huggingface dataset:
Spin valleytronics in silicene: Quantum spin Hall–quantum anomalous Hall insulators and single-valley semimetals

Valley-based electronics, known as valleytronics, is one of the keys to breaking through to a new stage of electronics. The valley degree of freedom is ubiquitous in the honeycomb lattice system. The honeycomb lattice structure of silicon, called silicene, is a fascinating playground of valleytronics. We investigate topological phases of silicene by introducing different exchange fields on the $A$ and $B$ sites. There emerges a rich variety of topologically protected states, each of which has a characteristic spin-valley structure. The single Dirac-cone semimetal is such a state where one gap is closed while the other three gaps are open, evading the Nielsen-Ninomiya fermion-doubling problem. We have newly discovered a hybrid topological insulator named the quantum spin\char21{}quantum anomalous Hall insulator, where the quantum anomalous Hall effect occurs at one valley and the quantum spin Hall effect occurs at the other valley. Along its phase boundary, single-valley semimetals emerge, where only one of the two valleys is gapless with degenerated spins. These semimetals are also topologically protected because they appear in the interface of different topological insulators. Such a spin-valley-dependent physics will be observed by optical absorption or edge modes.
PROBING THE X-RAY BINARY POPULATIONS OF THE RING GALAXY NGC 1291

We present Chandra studies of the X-ray binary (XRB) populations in the bulge and ring regions of the ring galaxy NGC 1291. We detect 169 X-ray point sources in the galaxy, 75 in the bulge and 71 in the ring, utilizing the four available Chandra observations totaling an effective exposure of 179 ks. We report photometric properties of these sources in a point-source catalog. There are ≈40% of the bulge sources and ≈25% of the ring sources showing >3σ long-term variability in their X-ray count rate. The X-ray colors suggest that a significant fraction of the bulge (≈75%) and ring (≈65%) sources are likely low-mass X-ray binaries (LMXBs). The spectra of the nuclear source indicate that it is a low-luminosity active galactic nucleus (AGN) with moderate obscuration; spectral variability is observed between individual observations. We construct 0.3–8.0 keV X-ray luminosity functions (XLFs) for the bulge and ring XRB populations, taking into account the detection incompleteness and background AGN contamination. We reach 90% completeness limits of ≈1.5 × 1037 and ≈2.2 × 1037 erg s−1 for the bulge and ring populations, respectively. Both XLFs can be fit with a broken power-law model, and the shapes are consistent with those expected for populations dominated by LMXBs. We perform detailed population synthesis modeling of the XRB populations in NGC 1291, which suggests that the observed combined XLF is dominated by an old LMXB population. We compare the bulge and ring XRB populations, and argue that the ring XRBs are associated with a younger stellar population than the bulge sources, based on the relative overdensity of X-ray sources in the ring, the generally harder X-ray color of the ring sources, the overabundance of luminous sources in the combined XLF, and the flatter shape of the ring XLF.
Is BZB J1450+5201 the most distant gamma-ray BL Lacertae object?

BL Lacertae (BL Lac) objects at high redshifts (z ≥ 2) are rarely detected. Through careful analysis of its Sloan Digital Sky Survey spectrum, BZB J1450+5201 is confirmed to be a high-z BL Lac object with z ≥ 2.471 by identifying the Lyα 1216 and CIV 1548/1550 absorption lines. This indicates that BZB J1450+5201 is the most distant BL Lac object discovered to date. Careful analysis of the five-year Fermi-LAT data of 2FGL J1451.0+5159 shows that its γ-ray emission is robust with a confidence level of 6. 2σ at 1–3 GeV and 6. 7σ at 3–10 GeV. This analysis with the five-year data overcomes confusion with its bright neighbor, which is a problem when analyzing the two-year data. In addition, 2FGL J1451.0+5159 is confirmed to be associated with BZB J1450+5201 using the five-year data. The analysis of multiwavelength data, from radio to γ-ray energies, indicates that BZB J1450+5201 is an intermediate synchrotron peaked (ISP) source. Its multiwavelength properties are consistent with distributions of other ISP sources at lower redshifts in the second Fermi-LAT AGN catalog. The pure synchrotron self-Compton (SSC) model seems to be disfavored, but the scattering of weak external emission plus the SSC process can provide a satisfactory description of the broadband emission.
The Blood-Brain Barrier in Bipolar Disorders: A Systematic Review

Background: Bipolar disorders (BD) are chronic, debilitating disorders. Our understanding of the pathogenesis and functional biomarkers in BD remains limited. The blood-brain barrier (BBB), a highly selective, protective physical barrier which separates the central nervous system from the peripheral circulation, has been increasingly investigated in the BD. This systematic review aimed to assess the relationship between BD and markers of BBB dysfunction. Methods: Studies were identified in PubMed and Medline databases in January 2021. Articles were limited to full-length peer-reviewed journal publications with no date restrictions. Included studies compared blood, CSF, post-mortem, genetic and imaging measures of BBB function in people with BD compared to healthy controls. Results: 49 studies were identified, 34 of which found an association between BD and markers of BBB dysfunction. Blood QAlb, S100B and MMP levels were found to be increased in BD participants compared to controls in 57% of the studies. In post-mortem BD studies, ICAM, neurexin, claudin-5, and chondroitin sulphate proteoglycans were increased in the anterior cingulate cortex (ACC), prefrontal grey matter, occipital cortex and cerebellum, and lateral nucleus of the entorhinal cortex respectively compared to controls. Additionally, a study of BBB leakage measured by MRI found that nearly 30% of BD participants had extensive BBB leakage compared to controls. The mood state of BD participants was also associated with markers of BBB dysfunction, with participants experiencing mania generally having increased BBB marker levels compared to participants who were depressed or in remission. Conclusions: This review suggests an association between BD and markers of BBB dysfunction. Further research is needed to control for a number of confounding factors, and to clarify whether this association provides a pathogenic mechanism, or is an epiphenomenon of BD.
Contamination of early-type galaxy alignments to galaxy lensing–CMB lensing cross-correlation

Galaxy shapes are subject to distortions due to the tidal field of the Universe. The cross-correlation of galaxy lensing with the lensing of the Cosmic Microwave Background (CMB) cannot easily be separated from the cross-correlation of galaxy intrinsic shapes with CMB lensing. Previous work suggested that the intrinsic alignment contamination can be $15\%$ of this cross-spectrum for the CFHT Stripe 82 (CS82) and Atacama Cosmology Telescope surveys. Here we re-examine these estimates using up-to-date observational constraints of intrinsic alignments at a redshift more similar to that of CS82 galaxies. We find a $\approx$ $10\%$ contamination of the cross-spectrum from red galaxies, with $\approx$ $3\%$ uncertainty due to uncertainties in the redshift distribution of source galaxies and the modelling of the spectral energy distribution. Blue galaxies are consistent with being unaligned, but could contaminate the cross-spectrum by an additional $9.5\%$ within current $95\%$ confidence levels. While our fiducial estimate of alignment contamination is similar to previous work, our work suggests that the relevance of alignments for CMB lensing-galaxy lensing cross-correlation remains largely unconstrained. Little information is currently available about alignments at $z>1.2$. We consider the upper limiting case where all $z>1.2$ galaxies are aligned with the same strength as low redshift luminous red galaxies, finding as much as $\approx$ $60\%$ contamination.
Extended Cosmic Ray Decreases with Strong Anisotropy after Passage of Interplanetary Shocks

The passage of an interplanetary shock and/or interplanetary coronal mass ejection often causes a rapid decrease in the Galactic cosmic-ray (GCR) flux, known as a Forbush decrease, followed by a recovery of the flux over some days. These local effects are of short duration and strongly rigidity dependent, with higher-rigidity particles exhibiting much weaker effects. In contrast, we present data for two events in which the cosmic-ray flux gradually decreased for about 1 week after shock passage, then recovering over the following week, with the highest anisotropy levels observed throughout Solar Cycle 24. These extended decreases have a weak rigidity dependence and are much more prominent in observations at higher cutoff rigidity, where the initial Forbush decrease is not clearly detected and other variations are generally weak, as we demonstrate using data from the Princess Sirindhorn Neutron Monitor at Doi Inthanon, Thailand with a cutoff rigidity of about 17 GV. We propose that these extended decrease events were initiated upon the passage of an interplanetary shock that inhibited the inflow of GCRs along the interplanetary magnetic field, possibly due to magnetic mirroring at the shock. We also discuss the general behavior of GCR anisotropy as observed at this high cutoff rigidity.
HAT-P-54b: A HOT JUPITER TRANSITING A 0.64 M⊙ STAR IN FIELD 0 OF THE K2 MISSION

We report the discovery of HAT-P-54b, a planet transiting a late K dwarf star in field 0 of the NASA K2 mission. We combine ground-based photometric light curves with radial velocity measurements to determine the physical parameters of the system. HAT-P-54b has a mass of 0.760 ± 0.032 ? > M J ? > , a radius of 0.944 ± 0.028 R J ? > , and an orbital period of 3.7998 ? > days. The star has V = 13.505 ± 0.060 ? > , a mass of 0.645 ± 0.020 ? > M ☉ ? > , a radius of 0.617 ± 0.013 ? > R ☉ ? > , an effective temperature of T eff ⋆ = 4390 ± 50 ? > , and a subsolar metallicity of [ Fe / H ] = − 0.127 ± 0.080 ? > . We also detect a periodic signal with P = 15.6 days and 5.6 mmag amplitude in the light curve, which we interpret as due to the rotation of the star. HAT-P-54b has a radius that is smaller than 92% of the known transiting planets with masses greater than that of Saturn, while HAT-P-54 is one of the lowest-mass stars known to host a hot Jupiter. Follow-up high-precision photometric observations by the K2 mission promise to make this a well-studied planetary system.
Hyperluminous reddened broad-line quasars at z ∼ 2 from the VISTA Hemisphere Survey and WISE all-sky survey

We present the first sample of spectroscopically confirmed heavily reddened broad-line quasars selected using the new near-infrared VISTA Hemisphere Survey andWide-fieldInfraredSurvey Explorer (WISE) all-sky survey. Observations of four candidates with (J − K) > 2.5 and K ≤ 16.5 over ∼180 deg 2 lead to confirmation that two are highly dust-reddened broad-line Type 1 quasars at z ∼ 2. The typical dust extinctions are AV ∼ 2-2.5 mag. We measure black hole masses of ∼10 9 Mand extinction-corrected bolometric luminosities of ∼10 47 erg s −1 , making them some of the brightest Type 1 quasars currently known. Despite this, these quasars lie well below the detection limits of wide-field optical surveys like the Sloan Digital Sky Survey (SDSS) with iAB > 22. We also present WISE photometry at 3-22 µm, for our full sample of spectroscopically confirmed reddened quasars including those selected from the UKIDSS Large Area Survey. We demonstrate that the rest-frame infrared spectral energy distributions of these reddened quasars are similar to ultraviolet-luminous Type 1 quasars with significant hot dust emission and starburst quasar hosts like Mrk 231. The average 12-µm flux density of our reddened quasars is similar to that of the recently discovered hyperluminous infrared galaxy (HyLIRG) WISE 1814+3412 (z = 2.452) at similar redshifts, with two of our reddened quasars also having comparable 22-µm flux densities to this extreme HyLIRG. These optically faint, heavily reddened broad-line quasars are therefore among the most mid- infrared-luminous galaxies at z ∼ 2, now being discovered using WISE.
Can backreaction prevent eternal inflation

We study the effects which the back-reaction of long wavelength fluctuations exert on stochastic inflation. In the cases of power-law and Starobinsky inflation these effects are too weak to terminate the stochastic growth of the inflaton field. However, in the case of the cyclic Ekpyrotic scenario, the back-reaction effects prevent the unlimited growth of the scalar field.
Derivative Chameleons

We consider generalized chameleon models where the conformal coupling between matter and gravitational geometries is not only a function of the chameleon field φ, but also of its derivatives via higher order co-ordinate invariants (such as ∂μφ∂ μφ,2φ, .). Specifically we consider the first such non-trivial conformal factor A(φ, ∂μφ∂ μφ). The associated phenomenology is investigated and we show that such theories have a new generic mass-altering mechanism, potentially assisting the generation of a sufficiently large chameleon mass in dense environments. The most general effective potential is derived for such derivative chameleon setups and explicit examples are given. Interestingly this points us to the existence of a purely derivative chameleon protected by a shift symmetry for φ→ φ+ c. We also discuss potential ghost-like instabilities associated with mass-lifting mechanisms and find another, mass-lowering and instability-free, branch of solutions. This suggests that, barring fine-tuning, stable derivative models are in fact typically anti-chameleons that suppress the field’s mass in dense environments. Furthermore we investigate modifications to the thin-shell regime and prove a no-go theorem for chameleon effects in non-conformal geometries of the disformal type. ∗Electronic address: johannes.noller08@imperial.ac. uk ar X iv :1 20 3. 66 39 v1 [ gr -q c] 2 9 M ar 2 01 2
In-medium heavy-quarkonium from lattice QCD spectral functions

We discuss recent progress in the study of in-medium heavy quarkonium using first-principles lattice QCD calculations and effective field theory. In particular our focus lies on real-time information carried by QCD spectral functions and we report on a novel strategy for their extraction from Euclidean-time simulations. Combining an effective description for heavy quarks with finite temperature lattice QCD we compute in-medium spectra providing insight in heavy quarkonium melting in a static thermal medium. On the other hand we use spectral information to extract the complex in-medium potential which provides the basis for a dynamical description of quarkonium real-time evolution via the Schrödinger equation.
Shell instability of a collapsing dense core

Understanding the formation of binary and multiple stellar systems largely comes down to studying the circumstances for the fragmentation of a condensing core during the first stages of the collapse. However, the probability of fragmentation and the number of fragments seem to be determined to a large degree by the initial conditions. In this work we study the fate of the linear perturbations of a homogeneous gas sphere both analytically and numerically. In particular, we investigate the stability of the well-known homologous solution that describes the collapse of a uniform spherical cloud. The difficulty of the mathematical singularity in the perturbation equations is surpassed here by explicitly introducing a weak shock next to the sonic point. In parallel, we perform adaptive mesh refinement (AMR) numerical simulations of the linear stages of the collapse and compared the growth rates obtained by each method. With this combination of analytical and numerical tools, we explore the behavior of both spherically symmetric and non-axisymmetric perturbations. The numerical experiments provide the linear growth rates as a function of the core's initial virial parameter and as a function of the azimuthal wave number of the perturbation. The overlapping regime of the numerical experiments and the analytical predictions is the situation of a cold and large cloud, and in this regime the analytically calculated growth rates agree very well with the ones obtained from the simulations. The use of a weak shock as part of the perturbation allows us to find a physically acceptable solution to the equations for a continuous range of growth rates. The numerical simulations agree very well with the analytical prediction for the most unstable cores, while they impose a limit of a virial parameter of 0.1 for core fragmentation in the absence of rotation.
Crystalline Kitaev spin liquids

Frustrated magnetic systems exhibit many fascinating phases. Prime among them are quantum spin liquids, where the magnetic moments do not order even at zero temperature. A subclass of quantum spin liquids called Kitaev spin liquids are particularly interesting, because they are exactly solvable, can be realized in certain materials, and show a large variety of gapless and gapped phases. Here, we show that non-symmorphic symmetries can enrich spin liquid phases, such that the low-energy spinon degrees of freedom form three-dimensional Dirac cones or nodal chains. In addition, we suggest how such Kitaev spin liquids may be realized in metal-organic-frameworks.
Quantum simplicial geometry in the group field theory formalism: reconsidering the Barrett–Crane model

A dual formulation of group field theories, obtained by a Fourier transform mapping functions on a group to functions on its Lie algebra, has recently been proposed. In the case of the Ooguri model for SO(4) BF theory, the variables of the dual field variables are thus bivectors, which have a direct interpretation as the discrete B variables. Here we study a modification of the model by means of a constraint operator implementing the simplicity of the bivectors in such a way that projected fields describe metric tetrahedra. This involves an extension of the usual group field theory (GFT) framework, where boundary operators are labeled by projected spin network states. By construction, the Feynman amplitudes are simplicial path integrals for constrained BF theory. We show that the spin foam formulation of these amplitudes corresponds to a variant of the Barrett–Crane model for quantum gravity. We then re-examine the arguments against the Barrett–Crane model(s) in light of our construction.
Towards the inclusion of wave-ice interactions in large-scale models for the Marginal Ice Zone

A wave-ice interaction model for the marginal ice zone (MIZ) is reported, which involves both the attenuation of ocean surface waves by sea ice and the concomitant breaking of the ice by waves. It is specifically designed to embed wave-ice interactions in an operational ice/ocean model for the first time. We investigate different methods of including the wave forcing, and different criteria for determining if they cause floes to break. We also investigate and discuss the effects of using various attenuation models, finding that predicted MIZ widths are quite sensitive to the choice of model. Additional sensitivity tests are performed on: (i) different parameterizations of the floe size distribution (FSD), including the initial FSD used; (ii) the properties of the wave field; and (iii) the sea ice properties such as concentration, thickness and breaking strain. Results are relatively insensitive to FSD parameterization but vary noticeably and systematically with its initial configuration, as they do with properties (ii-iii). An additional, somewhat surprising sensitivity, is the degree of influence of the numerical scheme that performs wave attenuation and advection. This is because a naive implementation of spatial and temporal discretizations can cause the waves to be over-attenuated, leading to a reduction of the predicted MIZ width by a substantial factor. Example simulations intended to represent conditions in the Fram Strait in 2007, which exploit reanalyzed wave and ice model data, are shown to conclude the results section. These compare favorably to estimates of MIZ width using concentrations obtained from remotely-sensed passive microwave images.
Near- and Mid-Infrared Imaging Study of Young Stellar Objects around LkHα 234

We present high-resolution (0: 2) near-infrared images of the area surrounding the Herbig Be star LkH˛ 234 taken with the Coronagraphic Imager with Adaptive Optics (CIAO) and the adaptive optics on the Subaru Telescope. The near-infrared (J , H , K, L 0 ,a ndM 0 bands) images reveal circumstellar structures around LkH˛ 234 in detail. Eight young stellar object (YSO) candidates (Object B, C, D, E, F, G, NW1, and NW2) were detected at 2 00 –11 00 from LkH˛ 234. Objects B and C are likely variable stars, which is consistent with a young evolutionary status. Three objects (LkH˛ 234, NW1, and NW2) were identified in the 11.8 � m (SiC) and 17.65 � m images obtained with the Long Wavelength Spectrometer (LWS) on the Keck Telescope. NW1 and NW2 are thought to be embedded young stars. We suggest that NW1, and not LkH˛ 234, is the source illuminating the reflection nebula west of LkH˛ 234, although Object G may be another candidate. In our images, these objects are located at the center of the 2 � m polarization, and NW1 resides at the center of a monopolar cavity. The SED of NW1 suggests that it is a YSO with a spectral type of B6–B7. Object F and G were discovered by our observations at 1: 00 9a nd 2: 00 3, respectively, from LkH˛ 234, and their proximity to LkH˛ 234 suggests that they may be its lower-mass companions.
Meaning in life, goals, and adherence to antiretroviral treatment in people living with HIV

ABSTRACT Patients living with HIV who do not adhere to antiretroviral treatment (ART) have a high viral load, increasing the risk of developing AIDS, as well as new treatment-resistant strains. There are several psychological factors that must be studied to understand the reasons for non-adherence to ART. We studied whether the goals reported by patients with HIV, as well as their sense of meaning in life, influence ART adherence in a sample of adult patients attending HIV outpatient care in Mexico. Participants completed the Antiretroviral Treatment Adherence Assessment Questionnaire, the Dimensional Scale of Meaning in Life and were asked to write both short-term and long-term goals. The most frequent goals reported were those categorized as “personal development,” followed by “being healthy. ” Participants with the highest adherence had more short-term “personal development” goals. Moreover, they showed the lowest levels of existential vacuum (lack of meaning in life). These variables predicted treatment adherence. We conclude that the design of programs to improve ART adherence should promote the establishment of personal development goals and offer tools that allow having a sense of meaning in life to reduce AIDS-related complications.