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As a form of body language, the gesture plays an important role in smart homes, game interactions, and sign language communication, etc. The gesture recognition methods have been carried out extensively. The existing methods have inherent limitations regarding user experience, visual environment, and recognition granularity. Millimeter wave radar provides an effective method for the problems lie ahead gesture recognition because of the advantage of considerable bandwidth and high precision perception. Interfering factors and the complexity of the model raise an enormous challenge to the practical application of gesture recognition methods as the millimeter wave radar is applied to complex scenes. Based on multi-feature fusion, a gesture recognition method for complex scenes is proposed in this work. We collected data in variety places to improve sample reliability, filtered clutters to improve the signal's signal-to-noise ratio (SNR), and then obtained multi features involves range-time map (RTM), Doppler-time map (DTM) and angle-time map (ATM) and fused them to enhance the richness and expression ability of the features. A lightweight neural network model multi-CNN-LSTM is designed to gestures recognition. This model consists of three convolutional neural network (CNN) for three obtained features and one long short-term memory (LSTM) for temporal features. We analyzed the performance and complexity of the model and verified the effectiveness of feature extraction. Numerous experiments have shown that this method has generalization ability, adaptability, and high robustness in complex scenarios. The recognition accuracy of 14 experimental gestures reached 97.28%. [ABSTRACT FROM AUTHOR]

Supramolecular glass is a non-covalently cross-linked amorphous material that exhibits excellent optical properties and unique intrinsic structural features. Compared with artificial inorganic/organic glass, which has been extensively developed, supramolecular glass is still in the infancy stage, and itself is rarely recognized and studied thus far. Herein, we present the development of the host–guest molecular recognition motifs between methyl-β-cyclodextrin and para-hydroxybenzoic acid as the building blocks of supramolecular glass. Non-covalent polymerization resulting from the host–guest complexation and hydrogen bonding formation enables high transparency and bulk state to supramolecular glass. Various advantages, including recyclability, compatibility, and thermal processability, are associated with dynamic assembly pattern. Short-range order (host–guest complexation) and long-range disorder (three dimensional polymeric network) structures are identified simultaneously, thus demonstrating the typical structural characteristics of glass. This work provides a supramolecular strategy for constructing transparent materials from organic components. Strategies to produce supramolecular glass and the study of its intrinsic structure and mechanical properties remains largely unexplored. Here, the authors prepare a supramolecular glass via the host–guest recognition between methyl-β-cyclodextrin and para-hydroxybenzoic acid with recyclability, compatibility, and thermal processability. [ABSTRACT FROM AUTHOR]

Cells in the brain are surrounded by extracellular space (ECS), which forms porous nets and interconnected routes for molecule transportation. Our view of brain ECS has changed from a largely static compartment to dynamic and diverse structures that actively regulate neural activity and brain states. Emerging evidence supports that dysregulation of brain ECS contributes to the pathogenesis and development of many neurological disorders, highlighting the importance of therapeutic modulation of brain ECS function. Here, we aim to provide an overview of the regulation and dysfunction of ECS in healthy and pathological brains, as well as advanced tools to investigate properties of brain ECS. This review emphasizes modulation methods to manipulate ECS with implications to restore their function in brain diseases. Highlights: • Up-to-date overview of the regulation of brain ECS in health and disease. • Recent advances in detecting the biophysical properties, function, and dynamic changes of brain ECS are reviewed. • Advanced pharmacological and physical methods to manipulate brain ECS, which provides therapeutic potentials for treating neurological disorders. [ABSTRACT FROM AUTHOR]

The Wangjiazhuang granitic pluton is located in the central Zanhuang Domain, the central part of the North China Craton, which is mainly composed of biotite monzogranite with few mafic microgranular enclaves. Biotite is an important ferromagnesian mineral in most of the intermediatefelsic igneous rocks, and its mineral chemistry can record the properties of magma and the petrogenetic physicochemical conditions. In this study, we carried out a detailed petrographic study by electric probe microanalysis on biotite for the biotite monzogranite and mafic microgranular enclaves, to discuss the source, physicochemical conditions, and the magma mingling/mixing processes of the Wangjiazhuang granite. The results show significantly different chemical compositions from the biotite monzogranite and mafic microgranular enclaves. The crystallization of these biotite grains from the biotite monzogranite and mafic microgranular enclaves all occurred in low oxygen fugacity. The biotite grains in biotite monzogranite are rich in Fe, poor in Mg, which belong to siderophyllite. The ratios of [(Fe3+ + Fe2+)/(Fe3+ + Fe2+ + Mg2+)] are between 0.78 and 0.86. The average of FeOT (total FeO)/MgO of biotite grains in biotite monzogranite is 9.02. The MF values [2 × Mg/(Fe2+ + Mg + Mn)] of biotite monzogranite are between 0.31 and 0.47, suggesting biotite monzogranite derived from crustal source rocks (metasedimentary rocks). The formation of granitic rocks including the Wangjiazhuang granite was related to the subduction event at ca. 2.5 Ga which resulted in the melting event, and then induced the early partial melting of TTGs and metasedimentary rocks. The biotite in mafic microgranular enclaves varies from siderophyllite to ferrobiotite, and MF values range from 0.63 to 1.06, suggesting that magma of mafic microgranular enclaves had experienced magma mixing/mingling in various degrees. Biotite monzogranite and parts of mafic microgranular enclaves have a similar crystallized condition, while other mafic microgranular enclaves are different from biotite monzogranite. The differences between biotite monzogranite and mafic microgranular enclaves may be a consequence of continuous interaction between granitic and mafic magmas. [ABSTRACT FROM AUTHOR]

Electron probe microanalysis (EPMA) dating of monazite has been developed over decades. However, limited by the detectability and analytical sensitivity of dating-related elements (Th, Pb, U and Y), the EPMA dating has been restricted to geological research. In this study, various probe currents, beam diameters and counting times have been utilized on a JEOL JXA-8230 electron microprobe to determine the optimal experimental conditions for measuring Th, Pb, U and Y in monazite. The optimal conditions are: (1) accelerating voltage is 15 kV; (2) probe current is 100 nA; (3) beam diameter is 1 μm; (4) the peak and background counting time of U and Pb are 200 and 100 s; and (5) the peak and background counting time of Th and Y are 100 and 50 s. We apply this method to monazite from garnet-bearing biotite gneiss in the Zanhuang area of the Central Orogenic Belt of the North China Craton. The PbO-ThO2* isochron age calculated by EPMA data is 1 812±17 Ma (MSWD=2.06), which is similar to the weighted mean 207Pb/206Pb age (1 805±12 Ma, MSWD=1.07) obtained by LA-ICP-MS. This study suggests that EPMA dating of monazite as a powerful dating technique can be widely used in geochronological study. [ABSTRACT FROM AUTHOR]

The Maillard reaction products (MRPs) prepared from aqueous equimolar glucose with 1 M cysteine model solution when heated at 110 °C for 1 h was previously recognized as strong browning inhibitors for banana fruit. This study investigated further the anti-browning ability of the fractionated fractions with different polarity using solvent extraction following a ultra-filtration with 3.5 ku MWCO membrane and characteristized antioxidant activity including DPPH• scavenging ability and reducing power, chelating copper activity, inhibitory ability and the inhibitory constants of banana PPO. Extracts with different polarity were obtained by methanol, ethanol, n-butanol and isopropanol, which were designated as MRP,MRP,MRP and MRP, respectively. Application of the Lineweaver-Burk plotting showed that all MRPs were mixed-type 1 inhibitors whose K was larger than corresponding K, with K values ranging between 0.297 and 0.035 mg/mL MRPs. MRP showed the strongest anti-browning ability from the visual observation, further evidenced by its lowest K and IC in terms of the inhibition of PPO activity and DPPH• scavenging ability, with a different anti-browning mechanism vs. NaSO. The strong copper chelating ability of the MRPs may account for the antioxidant ability and PPO activity inhibition to an extent. The effective anti-browning components from MRPs in glucose-cysteine model could be enriched by the combination of ultrafitration with ethanol extraction. And the extract may be applicable in food system. [ABSTRACT FROM AUTHOR]