Intrinsic Electronic Structure and Nodeless Superconducting Gap of YBa2Cu3O7−δ\mathrm{YBa_{2} Cu_{3} O_{7-\delta} } Observed by Spatially-Resolved Laser-Based Angle Resolved Photoemission Spectroscopy

The spatially-resolved laser-based high resolution ARPES measurements have been performed on the optimally-doped $\mathrm{YBa_{2} Cu_{3} O_{7-\delta} }$ (Y123) superconductor. For the first time, we found the region from the cleaved surface that reveals clear bulk electronic properties. The intrinsic Fermi surface and band structures of Y123 are observed. The Fermi surface-dependent and momentum-dependent superconducting gap is determined which is nodeless and consistent with the d+is gap form

Orbital-Dependent Electron Correlation in Double-Layer Nickelate La3Ni2O7

The latest discovery of high temperature superconductivity near 80K in La3Ni2O7 under high pressure has attracted much attention. Many proposals are put forth to understand the origin of superconductivity. The determination of electronic structures is a prerequisite to establish theories to understand superconductivity in nickelates but is still lacking. Here we report our direct measurement of the electronic structures of La3Ni2O7 by high-resolution angle-resolved photoemmission spectroscopy. The Fermi surface and band structures of La3Ni2O7 are observed and compared with the band structure calculations. A flat band is formed from the Ni-3dz2 orbitals around the zone corner which is 50meV below the Fermi level. Strong electron correlations are revealed which are orbital- and momentum-dependent. Our observations will provide key information to understand the origin of high temperature superconductivity in La3Ni2O7.Comment: 18 pages, 4 figure

Sharp Changes of Crustal Seismic Anisotropy Across the Central Tanlu Fault Zone in East China

Abstract Both seismic and geodetic data suggested that the ∼120‐km long Weifang segment of the Tanlu fault zone, a large‐scale active strike‐slip system at east China, is a seismic gap with no obvious along‐strike shear motion at surface. Measuring crustal deformation around the segment is crucial to constrain stress/strain buildup and potential seismic risk at the fault. We measured crustal and upper mantle seismic anisotropy using P‐to‐S converted waves at the Moho (Pms) and core‐mantle boundary (SKS) recorded by broadband arrays across the Weifang fault segment. The measured crustal anisotropy inside the fault zone shows a fast direction of ∼NNE, parallel to the fault orientation. Right east to the fault zone, the fast axis rotates by almost 90° to ESE. The crustal anisotropy within the fault zone could be caused by aligned microcracks and foliated minerals due to long‐lasting shear motion inside the fault zone

Superior multiphase interfaces in AgCuTe-based composite with significantly enhanced thermoelectric properties

It is common sense that a phase interface (or grain boundary) could be used to scatter phonons in thermoelectric (TE) materials, resulting in low thermal conductivity (κ). However, a large number of impurity phases are always so harmful to the transport of carriers that poor TE performance is obtained. Here, we demonstrate that numerous superior multiphase (AgCuTe, Ag2Te, copper telluride (Cu2Te and Cu2−xTe), and nickel telluride (NiTe)) interfaces with simultaneous strong phonon scattering and weak electron scattering could be realized in AgCuTe-based TE materials. Owing to the similar chemical bonds in these phases, the depletion region at phase interfaces, which acts as carrier scattering centers, could be ignored. Therefore, the power factor (PF) is obviously enhanced from ~609 to ~832 μW·m−1·K−2, and κ is simultaneously decreased from ~0.52 to ~0.43 W·m−1·K−1 at 636 K. Finally, a peak figure of merit (zT) of ~1.23 at 636 K and an average zT (zTavg) of ~1.12 in the temperature range of 523–623 K are achieved, which are one of the best values among the AgCuTe-based TE materials. This study could provide new guidance to enhance the performance by designing superior multiphase interfaces in the TE materials.</p

DLRAPom: a hybrid pipeline of Optimized XGBoost-guided integrative multiomics analysis for identifying targetable disease-related lncRNA-miRNA-mRNA regulatory axes

The lack of a reliable and easy-to-operate screening pipeline for disease-related noncoding RNA regulatory axis is a problem that needs to be solved urgently. To address this, we designed a hybrid pipeline, disease-related lncRNA-miRNA-mRNA regulatory axis prediction from multiomics (DLRAPom), to identify risk biomarkers and disease-related lncRNA-miRNA-mRNA regulatory axes by adding a novel machine learning model on the basis of conventional analysis and combining experimental validation. The pipeline consists of four parts, including selecting hub biomarkers by conventional bioinformatics analysis, discovering the most essential protein-coding biomarkers by a novel machine learning model, extracting the key lncRNA-miRNA-mRNA axis and validating experimentally. Our study is the first one to propose a new pipeline predicting the interactions between lncRNA and miRNA and mRNA by combining WGCNA and XGBoost. Compared with the methods reported previously, we developed an Optimized XGBoost model to reduce the degree of overfitting in multiomics data, thereby improving the generalization ability of the overall model for the integrated analysis of multiomics data. With applications to gestational diabetes mellitus (GDM), we predicted nine risk protein-coding biomarkers and some potential lncRNA-miRNA-mRNA regulatory axes, which all correlated with GDM. In those regulatory axes, the MALAT1/hsa-miR-144-3p/IRS1 axis was predicted to be the key axis and was identified as being associated with GDM for the first time. In short, as a flexible pipeline, DLRAPom can contribute to molecular pathogenesis research of diseases, effectively predicting potential disease-related noncoding RNA regulatory networks and providing promising candidates for functional research on disease pathogenesis

Orbital-dependent electron correlation in double-layer nickelate La3Ni2O7

Abstract The latest discovery of high temperature superconductivity near 80 K in La3Ni2O7 under high pressure has attracted much attention. Many proposals are put forth to understand the origin of superconductivity. The determination of electronic structures is a prerequisite to establish theories to understand superconductivity in nickelates but is still lacking. Here we report our direct measurement of the electronic structures of La3Ni2O7 by high-resolution angle-resolved photoemission spectroscopy. The Fermi surface and band structures of La3Ni2O7 are observed and compared with the band structure calculations. Strong electron correlations are revealed which are orbital- and momentum-dependent. A flat band is formed from the Ni-3d $${}_{{z}^{2}}$$ z 2 orbitals around the zone corner which is ~ 50 meV below the Fermi level and exhibits the strongest electron correlation. In many theoretical proposals, this band is expected to play the dominant role in generating superconductivity in La3Ni2O7. Our observations provide key experimental information to understand the electronic structure and origin of high temperature superconductivity in La3Ni2O7