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We explored the coupling between magnetic and magneto-transport properties in MnBi2Te4 crystals with Fermi energy EF ranging from 10 to 100 meV in the conduction band. Electrical, magnetic, and magneto-transport measurements reveal distinct behaviors depending on EF. At lower EF values (10 meV), MnBi2Te4 exhibits degenerate-semiconductor-like electrical transport and ferrimagnetism, with weak coupling between magneto-resistance and ferrimagnetism. In contrast, MnBi2Te4 displays metallic transport and antiferromagnetism (AFM) at higher Fermi energies, with magneto-resistance strongly coupled to antiferromagnetism and canted antiferromagnetism under a large external magnetic field. Remarkably, Hall measurements demonstrate a pronounced anomalous Hall resistivity (AHR) when the EF of MnBi2Te4 is 10 meV, larger than that reported for other bulk MnBi2Te4 crystals in the literature. Significant AHR is attributed to the Berry-phase effect in electronic-band structure based on first-principles calculation. The evolution of magnetic and magneto-transport properties in EF shifted MnBi2Te4 can be semi-quantitatively explained by the Ruderman–Kittel–Kasuya–Yosida interaction between neighboring MnTe layers. Our work suggests that the strongly Fermi-energy-sensitive magneto-transport properties observed in MnBi2Te4 may be useful in developing magnetic sensors/detectors. [ABSTRACT FROM AUTHOR]

The high-spin structure of 109 In was investigated with the 100 Mo (14 N , 5 n) 109 In fusion-evaporation reaction at CIAE, Beijing. Eleven new γ -rays of 109 In were identified, by which the bandheads of the Δ I = 2 rotational bands were confirmed. The configurations were assigned with the help of the systematic discussion. Furthermore, the rotational bands are compared with the tilted-axis cranking calculations based on a relativistic mean-field approach. The rotational bands involving the 1p1h excitation to the π d 5 / 2 and π g 7 / 2 orbitals are suggested as candidates for antimagnetic rotation based on the theoretical results. [ABSTRACT FROM AUTHOR]

The quantum spin Hall (QSH) effect is widely studied as a novel quantum state in condensed matter physics over the past decade. Recently, it is predicted that the transition metal pentatelluride XTe5 (X = Zr, Hf) has a large bandgap in its bulk form and a single layer of XTe5 is a QSH insulator candidate. However, the topological nature of the bulk material is still under debate because it is located close to the phase boundary of a strong topological insulator and a weak topological insulator (WTI). Here, using angle-resolved photoemission spectroscopy and scanning tunneling microscopy (STM)/scanning tunneling spectroscopy, we systematically studied the electronic structures of bulk HfTe5. Both the large bulk bandgaps and conductive edge states in the vicinity of the step edges in HfTe5 were observed, strongly suggesting a WTI phase in bulk HfTe5. Moreover, our STM experiment for the first time reveals the bulk band bending due to the broken symmetry near the step edge, making it an ideal platform for studying the development of edge states in the WTI and QSH insulator. [ABSTRACT FROM AUTHOR]

High-spin states in 92Nb have been investigated by using in-beam γ ray spectroscopy with the 82Se(14N,4n)92Nb reaction at a beam energy of 54 MeV. The positive-parity decay sequences above the previously known state 13+ have been extended to Iπ≥(20+) by adding nineteen new γ rays. The level structures in 92Nb have been interpreted in terms of the shell model calculations performed in the configuration space π(1f5/2,2p3/2,2p1/2,1g9/2) for the protons and ν(2p1/2,1g9/2,1g7/2,2d5/2) for the neutrons. The calculated results show that the inclusion of proton core excitation relative to the Z=38 subshell closure and neutron particle-hole excitation for the N=50 shell closure are essential to adequately describe the experimental high-spin states at I≈(18-20)ℏ with excitation energies above 8.5 MeV. [ABSTRACT FROM AUTHOR]

The high-spin structure of 109In has been investigated with the 100Mo(14N, 5n)109In reaction at a beam energy of 78 MeV using the in-beam γ spectroscopic method. The level scheme of 109In has been modified considerably and extended by 46 new γ rays to the highest excited state at 8.980 MeV and Jp=(45/2+). The new level scheme consists of eight bands, six of which are identified as dipole bands. The configurations have been tentatively assigned with the help of the systematics of neighboring odd-A indium isotopes and the experimental aligned angular momenta. The dipole bands are then compared with the titled axis cranking calculation in the framework of covariant density function theory. The results of theoretical calculations based on the configurations, which involve one proton hole at the g9/2 orbital and two or four unpaired neutrons at the g7/2, d5/2, and h11/2 orbitals, show that the shape of 109In undergoes an evolution on both β and γ deformations, and possible chirality is suggested in 109In. [ABSTRACT FROM AUTHOR]

The semimagic nucleus 89Y has been investigated using the 82Se(11B,4n) reaction at beam energies of 48 and 52 MeV. More than 24 new transitions have been identified, leading to a considerable extension of the level structures of 89Y. The experimental results are compared with the large-basis shell model calculations. They show that cross-shell neutron excitations play a pivotal role in high-spin level structures of 89Y. The systematic features of neutron-core excitations in the N=50 isotones are also discussed. [ABSTRACT FROM AUTHOR]

Objective: To determine the relative percentage of skeletal muscle mass (SMM) in elderly patients with coronary heart disease, analyse the relationship between percentage of SMM and cardiorespiratory fitness (CRF), predict exercise capacity and cardiac reserve. Methods: Patients aged 65 years and over after PCI, receiving cardiopulmonary exercise testing (CPET) during February 2014 to December 2016 in Department of Cardiology at Peking University Third Hospital were enrolled.All patients' basic data, percentage of SMM and CPET related parameters, including peak oxygen uptake (VO(2)peak), oxygen pulse (VO(2)/HR), oxygen uptake efficiency slope (OUES) and other cardiorespiratory endurance indicators were collected, to do correlation analysis. Results: There were 402 patients enrolled, with average age (71±5) years, including 283 cases of male (70.40%) and 119 cases of female patients (29.60%). There were 62 patients with acute myocardial infarction (15.42%), 113 patients with old myocardial infarction (28.11%), and 227 patients diagnosed with angina pectoris (56.47%). The percentage of SMM was correlated to CRF.The percentage of SMM[97.00 (92.05, 102.10)%] and VO(2)/HR ( r =0.231, P <0.001) and OUES ( r =0.264, P <0.001) were positively correlated.Body mass index was negatively correlated with VO(2)peak( r =-0.162, P =0.001). Visceral fat area (VFA) was also negatively correlated with VO(2)peak( r =-0.126, P =0.016). Multiple linear regression analysis showed that Body mass index and VFA were negatively correlated with VO(2)peak ( r =-0.204, P =0.014; r =-0.031, P =0.013). The percentage of SMM was positively independently correlated with OUES( r =11.020, P <0.001). Conclusions: Muscle content is positively correlated with exercise capacity of patients.The percentage of skeletal muscle mass determines the core index of cardiorespiratory fitness, such as the slope of oxygen pulse and oxygen uptake efficiency.These indexes can be used as an important criterion for predicting and guiding rehabilitation exercise in patients with coronary heart disease.

Hard coatings have been adopted in cutting and forming applications for nearly two decades. The major purpose of using hard coatings is to reduce the friction coefficient between contact surfaces, to increase strength, toughness and anti-wear performance of working tools and molds, and then to obtain a smooth work surface and an increase in service life of tools and molds. In this report, we deposited a composite CrTiSiN hard coating, and a traditional single-layered TiAlN coating as a reference. Then, the coatings were comparatively studied by a series of tests. A field emission SEM was used to characterize the microstructure. Hardness was measured using a nano-indentation tester. Adhesion of coatings was evaluated using a Rockwell C hardness indentation tester. A pin-on-disk wear tester with WC balls as sliding counterparts was used to determine the wear properties. A self-designed compression and friction tester, by combining a Universal Testing Machine and a wear tester, was used to evaluate the contact behavior of composite CrTiSiN coated dies in compressing of Mg alloy sheets under high pressure. The results indicated that the hardness of composite CrTiSiN coating was lower than that of the TiAlN coating. However, the CrTiSiN coating showed better anti-wear performance. The CrTiSiN coated dies achieved smooth surfaces on the Mg alloy sheet in the compressing test and lower friction coefficient in the friction test, as compared with the TiAlN coating., Competing Interests: The authors declare no conflict of interest.