Development of Financial Intermediation and the Dynamics of Rural-Urban Inequality: China, 1978-98

housing, transportation, planning, coordination, reform, equity, justice, inequality, central banks, China

Giant magnetic field from moir\'e induced Berry phase in homobilayer semiconductors

When quasiparticles move in condensed matters, the texture of their internal quantum structure as a function of position and momentum can give rise to Berry phases that have profound effects on materials properties. Seminal examples include the anomalous Hall and spin Hall effects from the momentum-space Berry phases in homogeneous crystals. Here we explore a conjugate form of electron Berry phase arising from the moir\'e pattern, the texture of atomic configurations in real space. In homobilayer transition metal dichalcogenides, we show the real-space Berry phase from moir\'e manifests as a periodic magnetic field up to hundreds of Tesla. This quantity tells apart moir\'e patterns from different origins, which can have identical potential landscape but opposite quantized magnetic flux per supercell. For low energy carriers, the homobilayer moir\'es realize topological flux lattices for the quantum spin Hall effect. An interlayer bias can continuously tune the spatial profile of moir\'e magnetic field, whereas the flux per supercell is a topological quantity that can only have a quantized jump observable at moderate bias. We also reveal the important role of the non-Abelian Berry phase in shaping the energy landscape in small moir\'e. Our work points to new possibilities to access ultra-high magnetic field that can be tailored in the nanoscale by electrical and mechanical controls

The Elderly Fall Detection Algorithm Based on Human Joint Extraction and Object Detection

Nowadays, the care of the elderly has become a social concern. The fall of the elderly has become one of the main factors threatening the health of the elderly. In this paper, we designed a fall detection algorithm based on human joint extraction and object detection.First,yolov4 was used to identify and detect the elderly. Then openpose was used to detect the human joint. Based on the human joint, this paper using Random Forest to classify the status of the elderly, there are three states of the elderly: falling down, lying down and other states. In the detection of a single old man, the accuracy of the model reached 99.3%, the sensitivity and specificity of the model reached 79.3% and 72.1%

A clickable oxysterol photolabel retains NMDA receptor activity and accumulates in neurons

Oxysterol analogs that modulate NMDA receptor function are candidates for therapeutic development to treat neuropsychiatric disorders. However, the cellular actions of these compounds are still unclear. For instance, how these compounds are compartmentalized or trafficked in neurons is unknown. In this study, we utilized a chemical biology approach combining photolabeling and click chemistry. We introduce a biologically active oxysterol analog that contains: (1) a diazirine group, allowing for the permanent labeling of cellular targets, and (2) an alkyne group, allowing for subsequent in situ visualization using Cu2+ catalyzed cycloaddition of an azide-conjugated fluorophore. The physiological properties of this analog at NMDA receptors resemble those of other oxysterols, including occlusion with other oxysterol-like compounds. Fluorescent imaging reveals that the analog accumulates diffusely in the cytoplasm of neurons through an energy-independent mechanism. Overall, this work introduces a novel chemical biology approach to investigate oxysterol actions and introduces a tool useful for further cell biological and biochemical studies of oxysterols.</p

Two-dimensional hourglass Weyl nodal loop in monolayer Pb(ClO2_{2})2_{2} and Sr(ClO2_{2})2_{2}

The hourglass fermions in solid-state materials have been attracting significant interest recently. However, realistic two-dimensional (2D) materials with hourglass-shaped band structures are still very scarce. Here, through the first-principles calculations, we identify the monolayer Pb(ClO$_{2}$)$_{2}$ and Sr(ClO$_{2}$)$_{2}$ materials as the new realistic materials platform to realize 2D hourglass Weyl nodal loop. We show that these monolayer materials possess an hourglass Weyl nodal loop circling around the $\Gamma$ point and Weyl nodal line on the Brillouin zone (BZ) boundary in the absence of spin-orbit coupling (SOC). Through the symmetry analysis, we demonstrate that the hourglass Weyl nodal loop and Weyl nodal line are protected by the nonsymmorphic symmetries, and are robust under the biaxial strains. When we include the SOC, a tiny gap will be opened in the hourglass nodal loop and nodal line, and the nodal line can be transformed into the spin-orbit Dirac points. Our results provide a new realistic material platform for studying the intriguing physics associated with the 2D hourglass Weyl nodal loop and spin-orbit Dirac points.Comment: 10 pages, 7 figures, Accepted for publication in New Journal of Physic