Microfacies and diagenetic alteration in a semi-deep to deep lacustrine shale: The Yanchang Formation in the Ordos Basin, China

The mineralogical development and diagenetic sequence of lacustrine shales in the Chang 7 Member of the Yanchang Formation in the Ordos Basin are detailed studied.A model of their depositional system and a diagenetic diagram are proposed in this study.Through detailed petrographic,mineralogical,and elemental analyses,four distinct shale types are identified:argillaceous shale,siliceous shale,calcareous shale,and carbonate,clay,and silt-bearing shale.The main diagenetic process in argillaceous shale is the transformation of illite to smectite,negatively impacting shale porosity.Siliceous shale undergoes carbonate cementation and quartz dissolution,contributing to increased porosity,particularly in mesopores.Calcareous shale experiences diagenesis characterised by carbonate formation and dissolution,with a prevalence of siderite.In carbonate,clay,and silt-bearing shale,the dissolution of K-feldspar contributes to illitization of kaolinite.Argillaceous shale,characterised by more clay minerals and lower mesopore volume,is identified as a potential hydrocarbon seal.Siliceous shale,with the highest pore volume and abundant inter-mineral pores,emerges as a promising shale oil reservoir.These findings contribute to a comprehensive understanding of shale properties,aiding in the prediction of shale oil exploration potential in the studied area.

Processing map and hot deformation behavior of Ta-particle reinforced TiAl composite

The hot deformation behavior of a Ta-particle reinforced TiAl composite was studied.Ti-48Al-2Cr-2Nb-0.2 W(at.%)/20 vol.%Ta metal matrix composite was fabricated by spark plasma sintering.The deformation behavior was investigated by hot compression tests at the temperature ranging from 1050 to 1200℃ and the strain rate ranging from 1×10-3 to 1 s-1.The constitutive equation containing true strain variables was established.The values of activation energy Q under different strain degrees are between 240 and 280 kJ/mol,which are lower than that of pure TiAl.Based on dynamic material modeling,the processing maps at various strain degrees were established,and the optimized parameters for hot working are 1050-1100℃ and 0.005-0.01 s-1.The microstructural evolution during deformation was characterized,which indicated that the dynamic recrystallization plays an important role in this process.

Ringing spectroscopy in the magnomechanical system

The ringing phenomenon has been studied in optical whispering gallery mode(WGM)resonators and can be used to sense the ultrafast process in spectroscopy.Here we observe the ringing phenomenon in a magnomechanical system for the first time,which is induced by the interference between the microwave photons converted from the damped phonons and the probing microwave photons.This interference eventually appears as a transparency window even along with the ringing phenomenon in the measured microwave reflection spectrum,which is influenced by the scanning speed and the input power.Then,the ringing spectroscopy is used to measure the coupling strength between the magnon and phonon modes,and outline the displacement profile of𝑆1,2,2 mechanical mode in a YIG microsphere,demonstrating the theoretical analysis.In addition,the ring-up spectroscopy is developed in our magnomechanical system,laying the foundation for fast sensing based on mechanical motion.

Nonreciprocal transition between two nondegenerate energy levels

Stimulated emission and absorption are two fundamental processes of light–matter interaction, and the coefficients of the two processes should be equal. However, we will describe a generic method to realize the significant difference between the stimulated emission and absorption coefficients of two nondegenerate energy levels, which we refer to as a nonreciprocal transition. As a simple implementation, a cyclic three-level atom system, comprising two nondegenerate energy levels and one auxiliary energy level, is employed to show a nonreciprocal transition via a combination of synthetic magnetism and reservoir engineering. Moreover, a single-photon nonreciprocal transporter is proposed using two one-dimensional semi-infinite coupled-resonator waveguides connected by an atom with nonreciprocal transition effect. Our work opens up a route to design atom-mediated nonreciprocal devices in a wide range of physical systems.

Novel thioredoxin reductase inhibitor butaselen inhibits tumorigenesis by down-regulating programmed death-ligand 1 expression

The thioredoxin system plays a role in a variety of physiological functions, including cell growth, differenti- ation, apoptosis, tumorigenesis, and immunity. We previously confirmed that butaselen （BS）, a novel thioredoxin reductase inhibitor, can inhibit the growth of various human cancer cell lines, yet the underlying mechanism remains elusive. In this study, we investigated the anti-tumor effect of BS in vivo through regulating the immune system of KM mice. We found that BS inhibits tumor proliferation by promoting the activation of splenic lymphocytes in mice. BS can elevate the percentage of CD^4-CD8^＋ T lymphocytes and the secretion of downstream cytokines in mice via downregulating the expression of programmed death-ligand 1 （PD-L1） on the tumor cells＇ surface in vivo. Further study in HepG2 and BEL-7402 cells showed that decrease of PD-L1 level after BS treatment was achieved by inhibiting signal transducer and activator of transcription 3 （STAT3） phosphorylation. Taken together, our results suggest that BS has a role in promoting the immune response by reducing PD-L1 expression via the STAT3 pathway, and subsequently suppresses tumorigenesis.

Synchronization in PT-symmetric optomechanical resonators

Synchronization has great impacts in various fields such as self-clocking,communication,and neural networks.Here,we present a mechanism of synchronization for two mechanical modes in two coupled optomechanical resonators with a parity-time(PT)-symmetric structure.It is shown that the degree of synchronization between the two far-off-resonant mechanical modes can be increased by decreasing the coupling strength between the two optomechanical resonators due to the large amplification of optomechanical interaction near the exceptional point.Additionally,when we consider the stochastic noises in the optomechanical resonators by working near the exceptional point,we find that more noises can enhance the degree of synchronization of the system under a particular parameter regime.Our results open up a new dimension of research for PT-symmetric systems and synchronization.