I review recent new lattice QCD results on a few selected topics which are relevant to the heavy ion physics community. Special emphasis is put on the QCD phase diagram towards the chiral limit and ...at nonzero baryon density as well as the fate of quarkonia and heavy quark drag coefficients.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fibrotic skin disease represents a major global healthcare burden, characterized by fibroblast hyperproliferation and excessive accumulation of extracellular matrix. Fibroblasts are found to be ...heterogeneous in multiple fibrotic diseases, but fibroblast heterogeneity in fibrotic skin diseases is not well characterized. In this study, we explore fibroblast heterogeneity in keloid, a paradigm of fibrotic skin diseases, by using single-cell RNA-seq. Our results indicate that keloid fibroblasts can be divided into 4 subpopulations: secretory-papillary, secretory-reticular, mesenchymal and pro-inflammatory. Interestingly, the percentage of mesenchymal fibroblast subpopulation is significantly increased in keloid compared to normal scar. Functional studies indicate that mesenchymal fibroblasts are crucial for collagen overexpression in keloid. Increased mesenchymal fibroblast subpopulation is also found in another fibrotic skin disease, scleroderma, suggesting this is a broad mechanism for skin fibrosis. These findings will help us better understand skin fibrotic pathogenesis, and provide potential targets for fibrotic disease therapies.
Fast radio bursts (FRBs), bright transients with millisecond durations at ∼GHz and typical redshifts probably >0.8, are likely to be gravitationally lensed by intervening galaxies. Since the time ...delay between images of strongly lensed FRB can be measured to extremely high precision because of the large ratio ∼10
between the typical galaxy-lensing delay time Formula: see text (10 days) and the width of bursts Formula: see text (ms), we propose strongly lensed FRBs as precision probes of the universe. We show that, within the flat ΛCDM model, the Hubble constant H
can be constrained with a ~0.91% uncertainty from 10 such systems probably observed with the square kilometer array (SKA) in <30 years. More importantly, the cosmic curvature can be model independently constrained to a precision of ∼0.076. This constraint can directly test the validity of the cosmological principle and break the intractable degeneracy between the cosmic curvature and dark energy.
We investigate the temperature dependence of the thermal dilepton rate and the electrical conductivity of the gluon plasma at temperatures of 1.1, 1.3, and 1.5T sub(c) in quenched QCD. Making use of ...nonperturbatively clover-improved Wilson valence quarks allows for a clean extrapolation of the vector meson correlation function to the continuum limit. We found that the vector correlation function divided by T super(3) is almost temperature independent in the current temperature window. The spectral functions are obtained by chi super(2) fitting of phenomenologically inspired Ansatze for the spectral function to the continuum extrapolated correlator data, where the correlations between the data points have been included. Systematic uncertainties arising from varying the Ansatze motivated from strong coupling theory as well as perturbation theory are discussed and estimated. We found that the electrical conductivity of the hot medium, related to the slope of the vector spectral function at zero frequency and momentum, is 0.2C sub(em) less than or approximate to sigma/T less than or approximate to 0.7C sub(em) for T=1.1T sub(c) and 0.2C sub(em) less than or approximate to sigma/T less than or approximate to 0.4C sub(em) for the higher temperatures. The dilepton rates and soft photon rates, resulting from the obtained spectral functions, show no significant temperature dependence, either.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
We investigate the chiral phase structure of three flavor QCD in a background U(1) magnetic field using the standard staggered action and the Wilson plaquette gauge action. We perform simulations on ...lattices with a temporal extent of N τ = 4 and four spatial extents of Nσ = 8, 16, 20 and 24. We choose a quark mass in lattice spacing as a m = 0.030 with corresponding pion mass estimated as m π ∼ 280 MeV such that there exists a crossover transition at vanishing magnetic fields, and adopt two values of magnetic field strength in lattice spacing a √eB ≃ 1.5 and 2 corresponding to eB/m2π ∼ 11 and 20, respectively. We find that the transition becomes stronger in the presence of a background magnetic field, and turns into a first order as seen from the volume scaling of the order parameter susceptibility as well as the metastable states in the time history of the chiral condensate. On the other hand, the chiral condensate and transition temperature always increase with B even within the regime of a first order phase transition. This suggests that the discrepancy in the behavior of chiral condensates and transition temperature as a function of B between earlier lattice studies using larger-than-physical pion masses with standard staggered fermions and those using physical pions with improved staggered fermions is mainly due to lattice cutoff effects.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
Organic molecules with second near‐infrared (NIR‐II, 1000–1700 nm) emission have significant advantages over NIR‐I (600–900 nm) dyes, and have been widely used as phototheranostic agents (PTAs) and ...fluorescent probes. However, the two biggest challenges for such reagents are improving photothermal conversion efficiency (PCE), and simplifying tedious synthetic procedures. Herein, different from the traditional NIR skeleton, for the first time, it develops two novel dibenzofulvene‐based NIR‐II emission PTAs via D‐π‐A concept with high PCEs through two simple synthetic steps. The increased intramolecular charge transfer effect and extended π‐conjugation effectively red‐shift their emissions to the NIR‐II region. In addition, the introduction of molecular rotors/vibrators and the formation of π–π stacking prompt the two PTAs to exhibit high PCEs. Notably, FE‐IDMN nanoparticles (FE‐IDMN NPs) achieve an exciting PCE of 82.6%, higher than most reported photothermal agents with NIR‐II emission. FE‐IDMN NPs also possess good colloidal, pH, and photothermal stabilities, as well as excellent photoacoustic response, which is further successfully applied for NIR‐II fluorescence/photoacoustic/photothermal imaging‐guided photothermal therapy. This work provides a simple strategy for constructing new D‐π‐A PTAs with low molecular weight, NIR‐II emission, and high PCE for cancer therapy.
A novel low‐molecular‐weight dibenzofulvene‐based D‐π‐A phototheranostic agent (PTA) with NIR‐II emission and high PCE is developed by the strategies of enhancing D‐A strength, introducing molecular rotors/vibrators, and facilitating intermolecular π–π stacking. The PTA is successfully applied in the multi‐modal imaging (NIR‐II fluorescence/photoacoustic/photothermal imaging)‐guided photothermal therapy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The unique properties of graphene are highly desired for printing electronics, coatings, energy storage, separation membranes, biomedicine, and composites. However, the high efficiency exfoliation of ...graphene into single- or few-layered nanoplates remains a grand challenge and becomes the bottleneck in essential studies and applications of graphene. Here, we report a scalable and green method to exfoliate graphene nanoplatelets (GNPs) from nature graphite in pure water without using any chemicals or surfactants. The essence of this strategy lies in the facile liquid exfoliation route with the assistance of vapor pretreatment for the preparation of edge hydroxylated graphene. The produced graphene consisted primarily of fewer than ten atomic layers. Such the water soluble graphene can be stored in the form of dispersion (~0.55 g L
) or filter cake for more than 6 months without the risk of re-stacking. This method paves the way for the environmentally friendly and cost-effective production of graphene-based materials.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
We report here a full-dimensional machine learning global potential surface (PES) for the rearrangement of methylhydroxycarbene (H
C-C-OH, 1t). The PES is trained with the fundamental invariant ...neural network (FI-NN) method on 91 564
energies calculated at the UCCSD(T)-F12a/cc-pVTZ level of theory, covering three possible product channels. FI-NN PES has the correct symmetry properties with respect to permutation of four identical hydrogen atoms and is suitable for dynamics studies of the 1t rearrangement. The averaged root mean square error (RMSE) is 11.4 meV. Six important reaction pathways, as well as the energies and vibrational frequencies at the stationary geometries on these pathways are accurately preproduced by our FI-NN PES. To demonstrate the capacity of the PES, we calculated the rate coefficient of hydrogen migration in -CH
(path A) and hydrogen migration of -OH (path B) with instanton theory on this PES. Our calculations predicted the half-life of 1t to be 95 min, which is excellent in agreement with experimental observations.
Abstract
The metal-support interfaces between metals and oxide supports have long been studied in catalytic applications, thanks to their significance in structural stability and efficient catalytic ...activity. The metal-rare earth oxide interface is particularly interesting because these early transition cations have high electrophilicity, and therefore good binding strength with Lewis basic molecules, such as H
2
O. Based on this feature, here we design a highly efficient composite Ni-Y
2
O
3
catalyst, which forms abundant active Ni-NiO
x
-Y
2
O
3
interfaces under the water-gas shift (WGS) reaction condition, achieving 140.6 μmol
CO
g
cat
−1
s
−1
rate at 300 °C, which is the highest activity for Ni-based catalysts. A combination of theory and ex/in situ experimental study suggests that Y
2
O
3
helps H
2
O dissociation at the Ni-NiO
x
-Y
2
O
3
interfaces, promoting this rate limiting step in the WGS reaction. Construction of such new interfacial structure for molecules activation holds great promise in many catalytic systems.
AbstractGround reaction curves (GRCs) are increasingly used to simulate the progressive development of soil arching resulting from differential movement in soil. In this study, 20 single, double, and ...multiple trapdoor tests were conducted under a simultaneous displacement mode (i.e., trapdoors settle simultaneously), while 8 double trapdoor tests were carried out under a successive displacement mode (i.e., trapdoors settle successively) to examine the evolution of soil arching including the parameters related to the GRCs. This study identified and analyzed the key parameters of the GRCs. For the trapdoor tests conducted under the simultaneous displacement mode, an increase of the fill height led to a decrease in the minimum pressure and its corresponding trapdoor displacement. Furthermore, the ultimate normalized pressure and recovery rate exhibited a decreasing trend with an increase of the fill height. As compared to the single and double trapdoor tests, the multiple trapdoor tests had similar initial soil arching, minimum normalized pressure, and its corresponding trapdoor displacement but a relatively lower stress recovery rate. In the trapdoor tests conducted with the successive displacement mode, the pressure on the first settled trapdoor decreased while it increased on the later settled trapdoor during the settlement of the first settled trapdoor. Conversely, during the settlement of the later settled trapdoor, the pressure on the first settled trapdoor increased, while it decreased on the later settled trapdoor. Analyzing the GRCs on the later settled trapdoor under the successive displacement mode revealed that the initial slope and ultimate pressure of the GRC decreased as the fill height increased.
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