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Aiming at the problem that traditional methods are difficult to fully utilize the rich spectral information in hyperspectral images (HSI) and fail to capture the complex higher‐order relations in hyperspectral data, which leads to limited classification performance extreme learning machine and fails to further improve the classification accuracy of HSIs, the authors propose the hypergraph convolutional extreme learning machine (HGCELM) method. The method not only inherits all the advantages of extreme learning machine (ELM), but also embeds hypergraph convolution for feature selection, which is capable of handling higher‐order relations. This enables HGCELM to capture more complex relationships between nodes and provide richer representation capabilities. At the same time, the training speed advantage of ELM is retained, thus speeding up the model training process. Experimental results show that the proposed algorithm achieves better accuracy compared to other clustering algorithms. [ABSTRACT FROM AUTHOR]

Speech recognition becomes increasingly important in the modern society, especially for human–machine interactions, but its deployment is still severely thwarted by the struggle of machines to recognize voiced commands in challenging real‐life settings: oftentimes, ambient noise drowns the acoustic sound signals, and walls, face masks or other obstacles hide the mouth motion from optical sensors. To address these formidable challenges, an experimental prototype of a microwave speech recognizer empowered by programmable metasurface is presented here that can remotely recognize human voice commands and speaker identities even in noisy environments and if the speaker's mouth is hidden behind a wall or face mask. The programmable metasurface is the pivotal hardware ingredient of the system because its large aperture and huge number of degrees of freedom allows the system to perform a complex sequence of sensing tasks, orchestrated by artificial‐intelligence tools. Relying solely on microwave data, the system avoids visual privacy infringements. The developed microwave speech recognizer can enable privacy‐respecting voice‐commanded human–machine interactions is experimentally demonstrated in many important but to‐date inaccessible application scenarios. The presented strategy will unlock new possibilities and have expectations for future smart homes, ambient‐assisted health monitoring, as well as intelligent surveillance and security. [ABSTRACT FROM AUTHOR]

Reprogrammable metasurface (RM) has been demonstrated as a key enabling technology for resolving the difficulties arising in conventional electromagnetic (EM) sensing strategies, and the RM‐enabled intelligent EM sensing has emerged as a new paradigm with many advanced functionalities that are thought to be impossible. However, the RM‐enabled sensing strategies developed so far are usually limited to the single‐scale sensing task and the cooperative target, since they are designed to operate at a single frequency band and have the relatively small view angle. To address the formidable challenges, here the concept of multi‐task multi‐scale intelligent sensing is proposed with algorithm‐driven distributed multi‐frequency RMs. For principle illustration, a proof‐of‐principle system working at S‐, C‐, and X‐bands is designed, and it is experimentally demonstrated that the system is capable of monitoring continuously the action behavior and healthy status of the target acting freely in real‐world indoor settings. It is faithfully expected that the presented strategy could open a new avenue in the areas of internet‐of‐things (IoTs), digital twins, and so on. [ABSTRACT FROM AUTHOR]

To assess the feasibility of the reactive MgO (RM) binder in preparing Cr2O3‐bearing castables, the degradation behavior of RM‐bonded Cr2O3‐bearing castables in CaO–Al2O3–Fe2O3–SiO2‐based steel‐making slag was investigated at 1600°C via refractory cup testing. The corrosion resistance and infiltration resistance of RM‐bonded castables were compared with hydratable alumina (HA)‐bonded and calcium aluminate cement (CAC)‐bonded castables with respect to the differences in phase composition and microstructure. Al2O3 grains in RM‐bonded castable were preferentially attacked by the slag compared with Mg(Al, Cr)2O4 spinel‐based matrix. The formation of spinel‐based and CaO·6Al2O3‐based solid solutions with volume expansion from slag/castable interactions suppressed slag infiltration into RM‐bonded castable matrix. Both experimental observations and thermodynamic calculations indicated that the in situ formed Mg(Al, Cr)2O4 spinel in RM‐bonded castables was the predominant reason leading to the superior slag corrosion resistance and infiltration resistance compared with HA‐bonded and CAC‐bonded Cr2O3‐bearing castables. [ABSTRACT FROM AUTHOR]

Refractory matrix is a key factor in determining the properties and performance and thus the lifetime of refractory materials. The particle gradation affected both the matrix composition and microstructure. In this study, six particle gradations of high‐alumina castables were prepared based on Andreasen's model (q = 0.22, 0.24, 0.26, 0.28, 0.30, and 0.32). The influence of particle gradation on properties of high‐alumina castables bonded with 4.0 wt% reactive MgO (RM) was investigated with respect to the difference in matrix composition and microstructure. The results show that castables with q values of 0.24 and 0.26 exhibited better physical and mechanical properties after curing and drying. The castables with a q value of 0.22 showed the best volume stability after firing at 1600°C, whereas, castables with a q value of 0.24 exhibited the highest mechanical strength, and residual CMOR ratio after thermal shock testing. Based on the property analyses of castables, the optimal q value of RM‐bonded castables would be around 0.24. [ABSTRACT FROM AUTHOR]

Alumina-chromia/aluminum-chromium/(AC) slag, is basically treated as hazardous solid waste. The present work reports the preparation of (Al,Cr) 2 O 3 - Mg(Al,Cr) 2 O 4 -Ca(Al,Cr) 12 O 19 composite refractory which is directly applicable to AC slag using reactive MgO as binder. Microstructure, mechanical properties and slag corrosion resistance to CaO-Al 2 O 3 -Fe 2 O 3 -SiO 2 -based slag of the prepared composite refractory were investigated. The results indicated that the obtained composites using AC slag aggregates exhibit superior corrosion resistance against the CaO-Al 2 O 3 -Fe 2 O 3 -SiO 2 -based slag compared with those with both AC slag aggregates and powders. Composites prepared using AC slag aggregates bonded with 5 wt% reactive MgO exhibited sufficient mechanical properties. This makes AC slag aggregates a possible candidate to prepare (Al,Cr) 2 O 3 - Mg(Al,Cr) 2 O 4 - Ca(Al,Cr) 12 O 19 composite refractory used in iron- and steel-making process. [ABSTRACT FROM AUTHOR]

Thysanoptera, commonly known as thrips, are diverse tiny insects whose earliest fossil record dates back to the Triassic period. Since there are few studies on the divergence time of taxa under Thysanoptera, this study used 13 mitochondrial coding protein genes to reconstruct the phylogenetic tree with divergence time of 26 species of this order and show a reliable phylogenetic relationship of thrips species. The time tree of this study shows that most extant thrips diverged in the early Tertiary period, while the fossil records also support that most extinct thrips appeared in this period. This study expands our understanding of the evolution of thrips and provides a feasible way of using multiple mitochondrial genes to establish robust phylogenetic relationships and explore divergence time between species. [ABSTRACT FROM AUTHOR]

Rare earth minerals are important strategic resources to economic development all over the world. In this study, multiple linear regression and back propagation (BP) neural network methods are used to invert the contents of ion adsorbed rare earth elements (REEs) and exploring the feasibility of quantitative inversion of REEs through measured hyperspectral data in Liutang rare earth mines, South China. The result shows that the spectral curve of the rare earth ore samples has obvious absorption characteristics around 390, 930, 1 400, 1 900 and 2 200 nm, and continuum removal and the 1st derivative treatment can highlight the absorption characteristics. The modeling accuracies of BP neural network are higher than that of multiple linear regression model. The BP neural network model of the 1st derivative data in 400–1 000 nm bands has the best inversion result of the total content of REEs, R2 reaches 0.98, the ratio of the performance to deviation (RPD) is larger than 3.0. The quantitative inversion model of each REE (except for Ce) has high precision, R2 is greater than 0.90 and RPD is greater than 3.0. The results indicate that quantitative inversion of REEs using measured spectra not only has great potential and feasibility in the exploration of rare earth minerals, but also provides a rapid test method for the content of ion-adsorbed rare earth elements. [ABSTRACT FROM AUTHOR]

A six degree-of-freedom (DOF) motion control system for docking with a deep submergence rescue vehicle (DSRV) test platform was the focus of this study. The existing control methods can meet the general requirements of underwater operations, but the complex structures or multiple parameters of some methods have prevented them from widespread use. The majority of the existing methods assume the heeling effect to be negligible and ignore it, achieving motion control in only four or five DOFs. In view of the demanding requirements regarding positions and inclinations in six DOFs during the docking process, the software and hardware architectures of the DSRV platform were constructed, and then sparse filtering technology was introduced for data smoothing. Based on the adaptive control strategy and with a consideration of residual static loads, an improved S-plane control method was developed. By converting the force (moment) calculated by the controller to the body coordinate system, the complexity of thrust allocation was effectively reduced, and the challenge of thrust allocation in the case of a high inclination during dynamic positioning was solved accordingly. The automatic control of the trimming angle and heeling angle was realized with the linkage system of the ballast tank and pump valve. A PID method based on an intelligent integral was proposed, which not only dealt with the integral "saturation" problem, but also reduced the steady-state error and overshooting. Water pool experiments and sea trials were carried out in the presence of water currents for six-DOF motion control. The responsiveness and precision of the control system were verified by the pool experiment and sea trial results and could meet the control requirements in engineering practice. The reliability and operational stability of the proposed control system were also verified in a long-distance cruise. [ABSTRACT FROM AUTHOR]

Optofluidic laser (OFL) technology, as an emerging technology combining microfluidics and laser technology, offers many unique advantages in sensing applications and has become a research hotspot for highly-sensitive intracavity biochemical analysis. Biochemical sensors based on OFLs can detect changes in biochemical parameters by using significant changes in laser output characteristics, so as to achieve high detection sensitivity. Here, we provide an overview of OFLs with a focus on their constructions, the design of OFL-based biochemical sensors, and their applications in biochemical analysis. Firstly, the three elements of an OFL, including the optical microcavity, gain medium, and pump source, are described systematically. After explaining the basic principles and characterization of OFLs for biochemical sensing, the current research progress of OFL-based biochemical sensors is summarized and analyzed according to the combination of OFLs with different assay techniques. This is followed by a discussion of the research on OFLs at the level of biological macromolecules, cells, and tissues. Finally, in view of the applications of OFLs in the field of biochemical sensing, the current challenges and future development directions are briefly discussed. [ABSTRACT FROM AUTHOR]

Cr2O3-bearing castables bonded with reactive MgO (RM) or calcium aluminate cement (CAC) were studied to evaluate the binder effect on their performance in corrosive environments. The properties of the as-prepared castables were compared with respect to the differences in phase composition and microstructure. The corrosion behavior of the as-prepared castables by CaO-Al2O3-Fe2O3-SiO2-based slag was systematically compared via refractory cup testing at 1 600 ℃ with respect to the differences in phase composition and microstructure. The analysis indicates that RM bonded castables show higher apparent porosity, lower bulk density and strengths after drying at 110 ℃ and firing at 1 300 ℃, and higher permanent linear change after firing at 1 300 ℃, but better slag corrosion and infiltration resistance compared with CAC bonded castables. [ABSTRACT FROM AUTHOR]

Bubbles, widely distributed in nature and industry, have been extensively explored as important energy carriers. Despite notable progress, how to harvest the energy inherent in small bubbles remains a significant challenge. Herein, a bubble driven triboelectric nanogenerator (BD‐TENG) that can scavenge energy directly and efficiently from bubbles is explored. The BD‐TENG can generate sustained voltages of up to −120 V when small air bubbles rise in a polytetrafluoroethylene (PTFE) tube filled with deionized water. Furthermore, the effects of the tube diameter, electrode length, and bubble volume based on the harvest activity are also investigated. As a proof of concept, it is demonstrated that the BD‐TENG can be utilized to illuminate four blue LEDs. Notably, the conclusion of this research work demonstrates an innovative roadmap for bubble energy harvesting in liquid media. [ABSTRACT FROM AUTHOR]

[Display omitted] Piezoelectric semiconductor zinc oxide (ZnO) shows promising applications in many fields, however, its excellent piezoelectric performance is limited by the intrinsic screening effect. Forming p-n junction through interface engineering is an effective strategy to enhance its piezoelectric output, but the unclear regulation mechanism is a bottleneck in developing high-performance devices. In this work, the enhancement mechanism of interface engineering on the piezoelectric performance of ZnO nanorods (NRs) based devices is revealed from the perspective of carrier concentration. Both the theoretical and experimental results show that the piezoelectric output is significantly correlated with the carrier concentration, which is mainly attributed to the suppression of screening effect and the modulation of the device capacitance. After a reasonable matching design of carrier concentration, the piezoelectric potential of the ZnO NRs-based device is greatly enhanced by about 12 times. Apparently, these findings provide a fresh insight to further understand the enhancement mechanism of interface engineering on the electrical output of piezoelectric semiconductor devices, and provide effective support for the design of p-n junction piezoelectric devices. [ABSTRACT FROM AUTHOR]

Hydratable alumina (HA) was premixed with hydromagnesite (BMC) to investigate the BMC impact on the hydration behavior of HA and the thermo-mechanical properties of HA bonded (HAB) castables. The phase composition, microstructure and mass changes of dried HA samples, were characterized by XRD, SEM, and TG, respectively. Flow ability, microstructure, and thermo-mechanical properties of HAB castables were studied. Results indicated that BMC effectively lowered HA hydration rate due to the decreased specific surface area. The hot modulus of rupture strength of castables was improved because the sintering of Al 2 O 3 was enhanced by the MgO from BMC decomposition. [ABSTRACT FROM AUTHOR]

Deep learning (DL) has demonstrated great potential in solving nonlinear electromagnetic inverse scattering (EMIS) problems. However, the lack of uncertainty quantification and reliability assessment in the predictions remains an unresolved challenge. Overcoming this challenge is of critical importance in practice because of the presence of uncertainties and noise in the measurement data and the ill-posedness of EMIS problems. Here, we propose a conditional renormalization and generation-flow (cRG-Flow) network, a reversible hierarchical network, and develop a novel probabilistic DL strategy to quantify the uncertainty in DL solutions of EMIS problems. The proposed strategy provides two other important advantages over the existing DL approaches for solving EMIS problems. First, due to the reversible property of cRG-Flow, both the forward EM scattering computation and its inverse procedure can be considered simultaneously in the network and, as a result, physical constraints on the DL solutions can be easily imposed. Second, the interpretability of DL solutions is facilitated due to the utilization of RG-Flow. Illustrative examples are provided to demonstrate the performance gain in terms of reconstruction quality and robustness. The proposed method may pave a new avenue for addressing the EMIS problems based on DL schemes with improved reliability and interpretability. [ABSTRACT FROM AUTHOR]

Tourism is evolving constantly as a result of the growth of the creative economy. Currently, ethnic cultural tourism is the focus of cultural tourism's overall development, while cultural tourism's development is primarily driven by considerations of social economy, cultural protection, and cultural inheritance. The first section of the article defines cultural and creative tourism. Second, this essay examines the evolution of creative and cultural tourism in general. In the end, cultural tourism's overall development is unquestionably superior to other development, and the other two commonly receive poor ratings. Its overall development score ranges from 4.4 to 4.9, and its average value without overall development is 4.42. The highest score is 4.89, with the average for cultural tourism with limited development being 4.49 and the average for cultural tourism with full development being 4.71. In a nutshell, the paper's proposal for evaluating the entire development of cultural tourism is doable. [ABSTRACT FROM AUTHOR]

In order to solve the problem of environmental pollution caused by construction waste, one typical waste of red bricks was selected as raw material in recycled concrete. This study presented recycled concrete by substituting some natural aggregates with treated red brick aggregates to study and analyze the degradation law mechanism of recycled brick aggregates concrete in the cold region. A total of fifteen categories of specimens and three experimental parameters were considered, which included numbers of freeze–thaw cycles (0, 50, and 100), steel fiber admixtures (0, 1, and 2%), and brick aggregate substitution rates (0, 25, 50, 75, and 100%), respectively. The quick freeze–thaw test method was selected to investigate recycled concrete's degradation mass loss rate and relative dynamic elastic modulus under various freeze–thaw cycles. The digital microscope and SEM were used to observe the internal microstructural changes in the specimens under different freeze–thaw times. In addition, the specimens' microscopic damage morphology and damage mechanism were analyzed. Finally, the flexural strength of the frost-damaged specimens was tested to analyze the mechanical deterioration of the recycled concrete, and the numerical model corresponding to steel fiber dosing and recycled aggregate replacement rate was presented. The gray correlation analysis was used to quantify the influence of each experimental variable on the corresponding experimental indexes under various freeze–thaw cycles. Results showed that the specimen's mass decreased after freeze–thaw cycles, and the highest mass loss was found for the specimens with 50 and 75% brick substitution rates. In addition, the specimens showed the best relative dynamic modulus and the maximum flexural strength when the steel fiber doping was 1%. The numerical model agreed with experimental data and effectively predicted the specimens' mass loss rate, relative dynamic modulus, and flexural strength after freeze–thaw cycles. The gray correlation analysis showed that the steel fiber contents had a maximum correlation with the flexural strength, the brick substitution rates for the relative dynamic modulus, and mass loss controls the freeze–thaw cycles. [ABSTRACT FROM AUTHOR]

The utilization of hydrogels in biological devices has seen a significant expansion, necessitating a thorough investigation into their conductivity. In this regard, we conducted a comprehensive examination of the impact of crosslinkers on pore radius and distribution. When the crosslinker proportion was augmented by a factor of 10, the pore radius exhibited a reduction of nearly 3.7 times, resulting in a more uniform pore distribution. Notably, our findings indicated a direct proportionality between conductivity and mesoscopic porosity, coupled with an inverse relationship with crosslinking density. To advance our understanding, we proposed an equivalent pore network model that omits considerations of curvature to predict the ionic conductivity of hydrogels. Intriguingly, as the proportion of crosslinker increased, the mesoscopic pores of hydrogels demonstrated a correlation with macroscopic features. Upon comparison with experimental data, the model exhibited a commendable alignment with the observed trends. Through mutual refinement with experimental results, a novel prediction equation emerged, yielding an average prediction error less than 2 %. Beyond trend prediction, our model achieved relative quantitative predictions, providing valuable insights for the regulation of conductivity in electronic biological devices. This research contributes to the advancement of knowledge in the field, offering a nuanced perspective on the interplay between crosslinkers, pore characteristics, and the conductivity of hydrogels. Hydrogels exhibit macroscopic continuity and mesoscopic porosity. Constructing an equivalent pore network model can establish a relationship between mesoscopic pores and macroscopic structures. [Display omitted] Given the increasing applications of hydrogels in biological devices, this study systematically investigated the ionic conductivity of hydrogels. The main highlights are as follows: • Examined the relationship between ionic conductivity and mesoscopic porosity, cross-link density, and their respective influences. • Leveraging the mesoscopic pore structure of hydrogels, and formulated a pore network model tailored for hydrogels. • Established a conductivity prediction model by connecting the mesoscopic pores of hydrogels with macroscopic aspects, incorporating the concept of macroscopic continuity and mesoscopic discontinuity. [ABSTRACT FROM AUTHOR]

The spin forming provides an approach to manufacturing large-diameter thin-walled complex curved surface components based on tailor-welded blanks produced from small 2195 Al-Li alloy plates, even scraps by friction stir welding (FSW). In this study, three spin forming schemes of single-pass, two-pass, and three-pass roller paths are designed. The corresponding experimental results indicate that the rolling of the rollers during spin forming is helpful in reducing the wall thickness inhomogeneity between weld and parent material and hence improves the surface roughness. Meanwhile, spin forming makes the welds deflect. With the increase of spinning passes, the forming height, open diameter, and the weld deflection angle of components increase. Additionally, the wall thickness difference, the surface quality, and the overall unfitability of components are all improved to some extent. However, there still exists insufficient forming height and over large open diameter due to the unfitability. Therefore, to obtain an ideal formed component, a spin forming scheme was proposed through increasing spinning passes in the ellipsoidal and cylindrical segments of the mandrel. Using this improved scheme, the forming height was increased with the maximum of 18%, the unfitability value was decreased with the maximum of 97%, the surface quality was significantly improved, and the ideal spun component was obtained. [ABSTRACT FROM AUTHOR]

Premise: The application of high‐throughput sequencing, especially to herbarium specimens, is rapidly accelerating biodiversity research. Low‐coverage sequencing of total genomic DNA (genome skimming) is particularly promising and can simultaneously recover the plastid, mitochondrial, and nuclear ribosomal regions across hundreds of species. Here, we introduce PhyloHerb, a bioinformatic pipeline to efficiently assemble phylogenomic data sets derived from genome skimming. Methods and Results: PhyloHerb uses either a built‐in database or user‐specified references to extract orthologous sequences from all three genomes using a BLAST search. It outputs FASTA files and offers a suite of utility functions to assist with alignment, partitioning, concatenation, and phylogeny inference. The program is freely available at https://github.com/lmcai/PhyloHerb/. Conclusions: We demonstrate that PhyloHerb can accurately identify genes using a published data set from Clusiaceae. We also show via simulations that our approach is effective for highly fragmented assemblies from herbarium specimens and is scalable to thousands of species. [ABSTRACT FROM AUTHOR]

The xenoliths in host rocks of hydrothermal gold deposits can generally provide much geochemical information of the deep rocks, which may have an implication for the sources of ore‐forming materials. Geochronology and geochemical characteristics are reported for a granite xenolith, which is enclosed by the lamprophyre in the Zhenyuan gold deposit (Yunnan Province, SW China). This granite xenolith mainly consists of K‐feldspar, quartz, and plagioclase with trace amounts of magnetite, titanite, apatite, zircon, and sulfides. Zircons from the granite xenolith yield a weighted average U‐Pb age of 281.1 ± 1.3 Ma (MSWD = 2.1), which could represent the crystallization age of this granite xenolith. The Ti‐in‐zircon geothermometer and the Mn concentration in apatite calculate that this granite xenolith formed at 685 ± 43°C with the logfO2 values ranging from NNO + 3.7 to NNO + 6.4. The zircons in the granite xenolith have a restricted range of positive ∊Hf(t) values ranging from +9.4 to +10.8, and the corresponding Hf TDM2 model ages range from 588 to 678 Ma. The zircon U‐Pb age and the Hf isotopic compositions indicate this granite xenolith within the lamprophyre is mainly derived from partial melting of juvenile crustal rocks before the completed closure of the Ailaoshan Ocean. The pyrites in the granite xenolith have higher Bi concentrations, and lower As, Sb, and Tl concentrations than the gold‐bearing pyrites of the ores in the Zhenyuan gold deposit. The low Au concentrations of the pyrites together with the ore‐forming age of the Zhenyuan gold deposit (Oligocene) indicate the granite xenolith may have limited contribution to the gold mineralization of the Zhenyuan gold deposit. [ABSTRACT FROM AUTHOR]

Change detection is an essential task in intelligent monitoring, and the accuracy of detection is of central importance for subsequent target tracking and recognition. However, a series of challenges such as illumination change, severe weather, shadow, and camera jitter have brought great troubles. To reduce the impact of these factors, we propose a novel model, called dual-branch enhanced network (DBEN), which can simultaneously extract enough spatial features and context information. Specifically, we design a recurrent gated bottleneck module to get high-level features, and build the global attention module as an auxiliary branch to obtain fine resolution details. Moreover, we also propose a gated residual dense module to enhance feature expression by reconstructing the combined information. Meanwhile, a weighted loss function is designed to optimize the network. The proposed DBEN is verified on CDnet2014, DAVIS and AICD, which are three large-scale change detection datasets. Experimental results show that the proposed model is competitive in overall performance. [ABSTRACT FROM AUTHOR]

The purpose of this study was to explore the function of the MarR family regulator slnO. Additionally, a high-yield strain of salinomycin was constructed using combined regulation strategies. First, the slnO gene overexpression strain (GO) was constructed in Streptomyces albus. Compared to the wild-type (WT) strain, salinomycin production in the GO strain increased by approximately 28%. Electrophoretic mobility gel shift assays (EMSAs) confirmed that the SlnO protein can bind specifically to the intergenic regions of slnN-slnO, slnQ-slnA1, and slnF-slnT. qRT-PCR experiments also showed that slnA1, slnF, and slnT1 were significantly upregulated, whereas the expression level of the slnN gene was downregulated in the GO strain. Second, the slnN gene deletion strain (slnNDM) was used as the starting strain, and the pathway-specific gene slnR in the salinomycin gene cluster was overexpressed in slnNDM. This new strain was named ZJUS01. The yield of salinomycin in the ZJUS01 strain was 25% and 56% higher than those in the slnNDM and WT strains, respectively. The above results indicate that the slnO gene has a positive regulatory effect on the biosynthesis of salinomycin. Meanwhile, the yield of salinomycin can be greatly increased by manipulating multiple transcriptional regulations. [ABSTRACT FROM AUTHOR]

Compared with printed Chinese characters, handwritten Chinese characters are affected by writing coherence and anthropic factors, resulting in differences in stroke deformation, displacement, tilt, length, and thickness. This consequently affects the recognition of handwritten Chinese characters. A method based on generative adversarial networks (GANs) of Chinese character handwriting-to-printing font conversion is proposed herein, where Chinese handwriting-to-printing font conversion is represented as a font style conversion and regarded as the optimal state of normalization of handwritten Chinese characters. First, an encoder–decoder is integrated into a generative adversarial network, and a symmetric network extracts handwritten font multi-scale information. Subsequently, U-Net with skip connection is used to extract deep features and reduce the large amount of low-level information shared between the input and output. Furthermore, the skip connection reduces information loss during down-sampling. Finally, the integration loss measures the differences in the character structure and font style between the generated Chinese character image and the target font image by combining font style, encoding consistency, and L 1 losses. An experiment to convert Chinese character handwriting to multiple printing fonts is performed on the CASIA and CASIA-HWDB1.1 datasets, in which image pixel difference and character recognition accuracy are used as evaluation metrics. The obtained results show a more normalized visual writing style and contribute to recognition improvement, thereby verifying the effectiveness of this method. [ABSTRACT FROM AUTHOR]

Soil organic carbon (SOC) is a key component of the carbon (C) cycle, and its accumulation is influenced by the stoichiometry of C: nitrogen (N): phosphorus (P), as well as microbial metabolism. However, the mechanisms driving SOC accumulation in agricultural and natural soils remain unclear. Therefore, this study aimed to investigate the impact of soil and microbial biomass (MB) C:N:P stoichiometry and microbial metabolic limitation on SOC accumulation in agricultural and natural soils. A survey of soils from 277 locations in eastern China was conducted, revealing that agricultural soils (paddy and upland soils) had 1.74-times higher SOC content than that of natural soils (wasteland and woodland soils). SOC showed a significant positive correlation with microbial C use efficiency (CUE), which in turn promoted SOC accumulation in agricultural soils. CUE was higher in agricultural soils (0.38–0.41) than in natural soils (0.25–0.31), which was attributed to reduced microbial metabolic limitation in agricultural soils. Increased nutrient supply was evident in agricultural soils, indicated by high SOC:TP, dissolved organic C:dissolved organic N, MBC:MBN, and MBC:MBP ratios, which alleviated microbial C and P limitations. However, in natural soils, low nutrient availability and enzyme activities resulted in significant microbial C and P limitations, thereby hindering SOC accumulation. Our results indicate that microbial metabolic limitation regulated by C:N:P stoichiometry stimulates SOC accumulation in agricultural soils, offering novel insights into SOC storage and emphasizing the importance of ecological stoichiometry and microbial metabolic limitation in SOC storage. [Display omitted] • Agricultural soils store more soil organic carbon than natural soils. • Carbon use efficiency was positively correlated with soil organic carbon. • Microbial C and P limitations negatively affected carbon use efficiency. • Decrease of the C:N:P stoichiometric ratios increased carbon use efficiency. [ABSTRACT FROM AUTHOR]

Antiferroelectric (AFE) ZrO2-based devices are anticipated to exhibit superior endurance properties in comparison to their ferroelectric (FE) counterparts. Nevertheless, the underlying mechanisms of AFE devices remain elusive. In this study, guided by the dynamic evolution of oxygen vacancies (Vo), we reveal three kinds of fatigue in AFE HfxZr1−xO2 (HZO) during uni-directional cycling. The first mechanism is related to the interfacial Vo charge trapping, which accelerates the switching from the P↓↑ state to the P↓↓ state, leading to extrinsic fatigue, and is demonstrated by electrical stress measurements. The other two mechanisms are Vo-related AFE to FE phase transition (PT) and Vo localization inside the HZO films, which are supported by the first-principles calculations. The highest polarization switching barrier occurs when Vo is localized at the tetra-coordinated oxygen sites inside HZO films. This means that tetra-coordinated Vo accumulation leads to less polarization switching, resulting in AFE to FE PT and Vo localization induced fatigue, i.e., intrinsic fatigue. This work reveals the dynamic evolution of Vo during cycling and its impact on AFE properties, paving the way for developing more durable AFE ZrO2-based devices and contributing to the emergence of diverse recovery methods in the future. [ABSTRACT FROM AUTHOR]

High‐silica granitoids record the formation and evolution of the continental crust. A new intrusive complex has been recognized among silicic volcanic rocks of the Weixi arc, Southwest China. The intrusions consist of granites, granitic porphyries, and granodiorites. Zircon U‐Pb age data indicate that the Weixi granitoids formed at 248–240 Ma and were coeval with silicic volcanic rocks of the Weixi arc. The Weixi granitoids are enriched in Rb, Th, and U, depleted in Ba, Sr, Nb, Ta, and Ti, and have high light/heavy rare earth element ratios and slightly negative Eu anomalies. The Weixi granitoids have negative εNd(t) values (–9.8 to –7.8) and negative zircon εHf(t) values (–12.02 to –5.11). The geochemical and isotopic features suggest the Weixi granitoids were derived by partial melting of ancient crustal material. The Weixi granitoids and silicic volcanic rocks were derived from the same magma by crystal accumulation and melt extraction, respectively, and they record the formation of a continental arc in the central Sanjiang orogenic belt. [ABSTRACT FROM AUTHOR]

Simple Summary: Wild chipmunks (Tamias sibiricus) eat and drink intermittently during hibernation. Instead of simply storing fat or food before hibernation, they use a mixed hibernation strategy. This experiment studied the histology of the colon, as well as changes in the composition and function of the gut microbiota of wild chipmunks during induced hibernation, aiming to explore how the gut microbiota of wild chipmunks performs its functions to better maintain normal physiological functions of the body during induced hibernation. The findings indicated that hibernation caused the increase of goblet cells in the colonic epithelial tissue of wild chipmunks, and increased the richness and diversity of the gut microbiota. The composition and function of the gut microbiota changed a lot, which could regulate the physiological metabolism of wild chipmunks during hibernation and better maintain their normal physiological functions. The gut microbiota plays a crucial role in the host's metabolic processes. Many studies have shown significant changes in the gut microbiota of mammals during hibernation to adapt to the changes in the external environment, but there is limited research on the colonic epithelial tissue and gut microbiota of the wild chipmunks during hibernation. This study analyzed the diversity, composition, and function of the gut microbiota of the wild chipmunk during hibernation using 16S rRNA gene high-throughput sequencing technology, and further conducted histological analysis of the colon. Histological analysis of the colon showed an increase in goblet cells in the hibernation group, which was an adaptive change to long-term fasting during hibernation. The dominant gut microbial phyla were Bacteroidetes, Firmicutes, and Proteobacteria, and the relative abundance of them changed significantly. The analysis of gut microbiota structural differences indicated that the relative abundance of Helicobacter typhlonius and Mucispirillum schaedleri increased significantly, while unclassified Prevotella-9, unclassified Prevotellaceae-UCG-001, unclassified Prevotellaceae-UCG-003 and other species of Prevotella decreased significantly at the species level. Alpha diversity analysis showed that hibernation increased the diversity and richness of the gut microbiota. Beta diversity analysis revealed significant differences in gut microbiota diversity between the hibernation group and the control group. PICRUSt2 functional prediction analysis of the gut microbiota showed that 15 pathways, such as lipid metabolism, xenobiotics biodegradation and metabolism, amino acid metabolism, environmental adaptation, and neurodegenerative diseases, were significantly enriched in the hibernation group, while 12 pathways, including carbohydrate metabolism, replication and repair, translation, and transcription, were significantly enriched in the control group. It can be seen that during hibernation, the gut microbiota of the wild chipmunk changes towards taxa that are beneficial for reducing carbohydrate consumption, increasing fat consumption, and adapting more strongly to environmental changes in order to better provide energy for the body and ensure normal life activities during hibernation. [ABSTRACT FROM AUTHOR]

Catalytic vapor-phase dehydration of glycerol is an energy-efficient and environmentally friendly route for producing acrolein, a valuable organic chemical intermediate. However, anti-coking is one of the key problems due to the excessively acid catalytic sites and sluggish mass transfer, restricting the industrial application of this reaction. Herein, potassium element modified BPO 4 monolithic foams with the hierarchically porous structure were synthesized by adding potassium element in the gel precursor of BPO 4. The catalyst introducing 3% K exhibited the best acrolein selectivity of 81.0% with nearly complete glycerol conversion. In a 10-hour run of the reaction at 320 °C, the selectivity of acrolein could remain at 75.9% with 94.5% glycerol conversion, indicating the superior stability. The excellent activity and stability for 3% K-BPO 4 is mainly attributed to the synergetic effect between hierarchical structure providing favorable mass transfer and appropriate acid catalytic sites inhibiting over dehydration reaction. They not only boost activity but also reduce coking, providing a unique approach for the design of solid acid catalyst. [Display omitted] • Hierarchical pore of K-modified BPO 4 catalyst is conducive to mass transfer. • The catalyst had adjustable acidity and encouraging resistance to carbon deposition. • The catalyst exhibited good conversion, selectivity, and stability in glycerol dehydration. [ABSTRACT FROM AUTHOR]

With the aim of achieving carbon neutrality, bio-based construction is of increasing interest for decarbonization globally. Among the potential candidates, straw bale is promising due to its ready availability and energy efficiency benefits. However, thermal conductivities of straw bales can vary greatly due to construction details, which may lead to failures in meeting nearly-zero energy building (nZEB) design standards in real practice. In the context, this study applied thermal property and carbon emission assessment of full-size straw bale walls (SBWs) and construction of an experimental building in northern China. The results demonstrated that the thermal conductivities of different monitoring portions of the SBWs ranged from 0.067 to 0.088 W·m−1·K−1. This resulted in U-values (0.16 W·m−2·K−1) marginally higher than the lower limits of nZEB design, indicating the importance of addressing thermal bridging issues of SBWs. The SBWs without additional insulation layers therefore can satisfy nZEB design standards in the severe cold region after certain adjustments. Besides, when not accounting for carbon sequestration, SBWs generated the lowest emissions among the schemes in meeting U-value limits for nZEB design (at least 14.6% lower than those of timber walls), with increasing emission reductions as U-value limit decreased. The results indicated that SBW demonstrated effectiveness in carbon reductions with high thermal performance. The findings of the research can facilitate application of straw bales and development of clean construction and net-zero design in northern China. [ABSTRACT FROM AUTHOR]

Coccolithophores are a group of phytoplankton widely distributed in the ocean, which secrete extracellular calcite plates termed coccoliths. Coccoliths have been increasingly employed as an archive for geochemical, ecological and paleoclimate studies in recent years. A robust application of coccolith-based geochemical proxies relies on understanding the carbon acquisition strategies and the pathways of carbon supply for calcification. Carbonic anhydrase (CA) plays important roles in the carbon concentrating mechanism s of aquatic algae and potentially also in calcification. However, it is difficult to independently assess the role of CA in carbon supply for photosynthesis versus calcification. To fill this gap, we explored a new method to detect the CA activity inside coccolithophore. To achieve this, coccolithophores were cultured with oxygen and carbon isotope labeled dissolved inorganic carbon (DIC). By exploiting the different behavior of oxygen and carbon isotopes with (sea)water, this double label method can elucidate the significance of CA activity in the calcification pathway. Application of this method to Emiliania huxleyi shows that CA is present in the calcification pathway, and that there is no significant difference in the CA activity between a high and low CO 2 treatment. However, under low CO 2 treatment E. huxleyi enhanced the bicarbonate pumping rate on both cell and chloroplast membranes. This novel method could be performed on other species of coccolithophores in the future and have a potential to extend our knowledge on coccolith oxygen isotope vital effects. [ABSTRACT FROM AUTHOR]

Both the first and the second derivatives of the chemical potential with respect to the temperature, for any system of noninteracting bosons, are shown to be negative. For noninteracting fermions, these derivatives can be either negative or positive, but for generic spectra they are both negative at higher temperatures. [ABSTRACT FROM AUTHOR]

A hybrid numerical method for heat conduction of functionally graded plate with the variable gradient parameters under the H(t) heat source was studied. A weighted residual equation of heat conduction was considered under thermal boundary conditions. In order to calculate temperature distribution of functionally graded plate with variable gradient parameters, the Fourier transform and inverse Fourier transform were applied and the temperature field was obtained under the H(t) heat source. Results show that the influences of the gradient parameters on temperature distribution are dramatic. But with the increase of gradient parameters, the influences of parameters on the temperature distribution are gradually reduced. When the gradient parameters reach a certain critical value, the temperature does not change anymore. By comparing the temperature distribution of the upper and lower surfaces, it is seen that the temperature presents a gentle downward trend with the increase of the heat source distance, while the temperature does not change with the time in farther distance from heat source. Also, the results show that the influence of the heat source has only partial and limited influence on the temperature, which is in accordance with St. Venant's Principle. The law of the temperature distribution of the lower surface varies with the gradient parameters, which is also discussed, an optimal gradient parameter with the thermal insulation effect of the functionally graded plate is obtained. [ABSTRACT FROM AUTHOR]

Hyperspectral image has excellent spectral information and abundant spatial information, and its feature quality is one of the key factors affecting the classification performance. Extreme learning machine (ELM) is widely used in hyperspectral classification problems. However, traditional ELM is usually based on regular Euclidean data, ignoring the inherent structured information between hyperspectral pixels, resulting in poor robustness. In this paper, we propose a new supervised extreme learning machine framework, termed spatial-spectral graph convolutional ELM (SSG-ELM), based on using graph convolution to extend ELM into the non-Euclidean domain. The method inherits all the advantages from ELM, and consists of a random graph convolutional layer followed by a graph convolutional regression layer, enabling it to model complex intra class variations. Otherwise, a local spectral-spatial context integration and reshaping mechanism is incorporated into the hidden layer feature representation by using a context-aware bilateral filtering procedure. Experimental results show that the proposed algorithm obtains a competitive performance and outperforms other state-of-the-art ELM-based methods. [ABSTRACT FROM AUTHOR]

This paper considers the identification of feedback nonlinear systems with unknown time delay (FNTD) by the chaotic decreasing weight sparrow search algorithm (CWSSA). The CWSSA algorithm uses the improved circle chaos to map the sparrow population, which avoids the problems of clustering and low coverage in the solution space of the initial solution. Thus, the global search ability and convergence speed of the algorithm are improved. By introducing a linear decreasing weight, the risk of the sparrow search algorithm being prone to premature maturity is reduced, and the oscillation phenomenon that is easy to occur near the global optimal solution in the later stage of the algorithm is avoided. Using the search capability of CWSSA and the iterative identification technology, all parameters and the unknown delay of the FNTD system are estimated simultaneously. Finally, the identification results of CWSSA, SSA and PSO are compared through a numerical example. The results show that CWSSA is superior to SSA and PSO in terms of convergence speed and estimation accuracy. The effectiveness of the CWSSA is also verified by the identification of the electro-hydraulic servo position system. [ABSTRACT FROM AUTHOR]

Lamprophyres typically appear in hydrothermal gold deposits. The relationship between lamprophyres and gold deposits is investigated widely. Some researchers suggest that the emplacement of lamprophyres triggers gold mineralization, whereas others hypothesize that the formation of lamprophyres increases the fertility of mantle sources and ore‐forming fluids. K‐feldspar veins, with ages between those of lamprophyres and gold deposits, appear in lamprophyres in Zhenyuan. Therefore, K‐feldspar veins are ideal for investigating the relationship between lamprophyres and gold deposits. Phlogopite in K‐feldspar veins has lower Mg#, Ni, and Cr contents and higher TiO2, Li, Ba, Sr, Sc, Zr, Nb, and Cs contents than phlogopite in lamprophyres. The in‐situ Sr isotopic values of apatites (0.7063–0.7066) in K‐feldspar veins are within the range for apatites (0.7064–0.7078) from lamprophyres. High large‐ion lithophile element concentrations and low Nb and Ta concentrations in phlogopite from lamprophyres, in addition to high (87Sr/86Sr)i values of apatite (0.7064–0.7078), indicate that the magma parental to these phlogopite and apatite crystals is derived from an enriched mantle. K‐feldspar veins are genetically correlated with lamprophyres, whereas sulfide mineral assemblage and trace element compositions of pyrite in K‐feldspar veins suggest that K‐feldspar veins in lamprophyres are not directly related to gold mineralization of the Zhenyuan deposit. [ABSTRACT FROM AUTHOR]

The Paleo-Tethyan tectonic evolution of the central Sanjiang orogenic belt remains unclear, particularly regarding the types and tectonic setting of volcanic rocks in the Cuiyibi Formation in the Weixi area, southwest China. These volcanic rocks were previously thought to be bimodal, but our detailed geological mapping revealed that the Cuiyibi Formation volcanic rocks include basalt, andesite, and rhyolite. In this paper, we present new geological, geochronological, and geochemical data for the andesitic rocks in the Cuiyibi Formation. Zircon U Pb ages of the andesitic rocks indicate they formed at 245–242 Ma. The andesitic rocks are part of the high-K calc-alkaline/shoshonite series, and they exhibit light rare earth and large-ion lithophile element (e.g., K, Rb, Th, and U) enrichment and heavy rare earth and high-field-strength element (e.g., Nb, Ta, and Ti) depletion. High Mg# values and Nb contents, low Sm/Yb and Lu/Yb ratios, and negative zircon ε Hf (t) and whole-rock ε Nd (t) values suggest these rocks were derived from an enriched mantle source. The Cuiyibi Formation volcanic rocks are geochemically similar to those formed in a continental arc. These rocks formed along a vast continental arc in the North Qiangtang–Lanping–Simao Block related to the subduction of the Paleo-Tethyan oceanic slab. • A new suite of andesitic rocks was identified in the central Sanjiang belt. • The andesitic rocks were erupted during the Middle Triassic. • A vast continental arc formed in response to subduction of the Paleo-Tethys. [ABSTRACT FROM AUTHOR]

Modern collisional orogens represent the natural laboratory for the study of metallogeny in continental collision zones. The Pyrenees, Alps, Zagros and Himalaya are all associated with Neo-Tethyan subduction and represent the youngest collisional orogens on Earth. Here, we compare these four orogens in terms of their composition, architecture, tectonic evolution, and metallogenic systems. The four orogens can be divided into simple and composite types. Simple orogens are represented by the Pyrenees and the Alps, and are characterized by narrow linear shapes in plain view and symmetric structures in cross-section, are free of arc magmatism, and are associated with the Mississippi Valley Valley-type Pb-Zn and orogenic gold deposits. The mineral deposits that form in these simple collisional orogens are generally related to processes that occur in the middle and upper crust. In contrast, composite orogens, as exemplified by the Zagros-Iranian and Himalayan-Tibetan Plateaus, are associated with broad orogenic plateaus in plain view and asymmetrical structures in cross-section, record extensive arc magmatism in continental margins, and are associated with a variety of deposit types including carbonatite-related rare earth element (REE), porphyry Cu-Mo, orogenic Au, Mississippi Valley type Pb-Zn, and detachment-fault-related polymetallic deposits. Although the subduction of Neo-Tethys oceanic crust occurred before the creation of simple collisional orogens in the Pyrenees and the Alps, these areas do not show the record of continental arc magmatism. In contrast, the composite collisional orogens are associated with the development of huge continental margin arcs prior to continental subduction, and the subduction was followed by reactivation of the subduction-modified arc lithospheric material, generating the ore-forming systems in these regions. [ABSTRACT FROM AUTHOR]

High mobility spin-polarized two-dimensional electron gas (2DEG) is crucially important for spintronic applications. Here, we report our investigations on the 2DEG fabricated by spin coating a LaAlO3 layer on a (001) SrTiO3 substrate with a La2/3Sr1/3MnO3 buffer layer. When the buffer layer is below 3 uc, the 2DGE is highly mobile. Corresponding to the layer thicknesses of 0, 1, and 2 uc, the Hall mobilities are ∼24 000 cm2/V s, ∼28 000 cm2/V s, and ∼59 600 cm2/V s at 2 K. In contrast, the 2DEG with a buffer layer of 3 uc shows a relatively low mobility (∼3000 cm2/V s). However, an anomalous Hall effect was observed in this 2DEG below 20 K, indicating a long range ferromagnetic order. This work demonstrates the great potential of the chemical method in gaining high quality spin-polarized 2DEGs at the LaAlO3/SrTiO3 interface. [ABSTRACT FROM AUTHOR]

Pyrite, the most common sulfide mineral, is a ubiquitous component of many hydrothermal gold deposits. Geochemical patterns within the refractory pyrite structure represent a valuable repository of information that can help constrain the sources of ore-forming materials, and the evolution of ore-forming processes over time. However, there are still a lot of debates on the mechanisms of physico-chemical processes in ore-forming fluid controlling trace element and sulfur isotope distributions in pyrite during growth. In our manuscript, we use cutting-edge complementary microanalytical methods to understand the origin and evolution of zoned gold-bearing pyrite in samples from the largest gold deposit in the Ailaoshan gold belt, SW China, Zhenyuan (exceeding 100t Au, average grade: 5.3 g/t). Pyrite, arsenopyrite, chalcopyrite, and stibnite are the most abundant sulfide minerals in most orebodies. Of these, pyrite is dominant and is also the most important host for gold. Two types of pyrite can be clearly distinguished: framboidal pyrite and hydrothermal pyrite. Gold is most commonly hosted by hydrothermal pyrite. Framboidal pyrite, mainly hosted by carbonaceous slate, hosts negligible Au, and features low δ34S values ranging from − 35.0 (± 0.9) to − 25.6 (± 1.0)‰. Hydrothermal pyrite is characterized by complex intra-grain zoned textures with alternating As-rich and As-poor bands readily recognizable on backscattered electron images. Scanning electron microscopy and trace-element analyses show that both visible and invisible gold occur only in the As-rich bands. Compared to the As-poor bands (72.1% of Au concentration data < 1.96 ppm, n = 43), the As-rich bands are characterized by far higher concentrations of Au (up to 1420 ppm), Cu, Ag, Sb, and Tl, but lower concentrations of Co and Ni. In-situ sulfur isotope analysis indicates that the δ34S values of As-rich zones range from − 7.3 (± 0.6) to 2.9 (± 0.6)‰ and are similar to those of As-poor zones (from − 6.9 (± 0.7) to 2.8 (± 0.6)‰), but distinct from the framboidal pyrite. Combined with published fluid inclusion data and a probable age for the magmatic event associated with mineralization, these data suggest that magmatic–hydrothermal fluids contributed most ore-forming materials and that periodic boiling led to formation of the rhythmic As-rich and As-poor bands in pyrite. Our data for pyrite constrain the evolution of ore-forming processes and provide new insights into the formation of zoned pyrite, with the conclusions having broad implications for analogous hydrothermal gold deposits worldwide. [ABSTRACT FROM AUTHOR]

Two-dimensional electron gas (2DEG) has abundant properties, which motivate not only fundamental physical interest but also concepts for device designing. While most of the reported 2DEGs are based on SrTiO3, here we report on a systematic investigation on anatase TiO2-based 2DEG generated by ion irradiation. By irradiating the surface layer of the anatase TiO2 films with appropriate argon ion beams, we gained the 2DEGs with a thickness of 4 nm. Unique transport behaviours of a T−1/3 or ln(1/T) sheet resistance dependence below 100 K are observed depending on irradiation time. Unusually large positive MR is observed for which the magnetic field causes a strong shrinkage of electron wave functions, and fairly large negative MR is detected in the 2DEG, arising from the depression of magnetic scattering. [ABSTRACT FROM AUTHOR]

Fault zones control the locations of many ore deposits, but the ore-forming processes in such fault zones are poorly understood. We have studied the deformation and ore textures associated with fault zones that controlled the lead–zinc mineralization of the Dongmozhazhua deposit, central Tibet, ∼100 km southwest of Yushu City. Geological mapping shows that the structural framework of the Dongmozhazhua area is defined by NW–SE-trending reverse faults and superposed folds that indicate at least two stages of deformation. The first stage is characterized by tight nearly E–W-striking folds that formed during the closure of the Jinshajiang Paleo-Tethyan Ocean in the Triassic. The second stage of deformation produced NW–SE-trending reverse faults and related structures of the Fenghuoshan–Nangqian fold-and-thrust belt associated with India–Asia collision in the late Eocene to Oligocene. Scanline surveys along the ore-controlling fault zones show an internal structure that comprises a damage zone, a breccia zone with clasts that have become rounded, and a breccia zone with lenticular clasts, and this complex architecture was formed during at least two compressional substages of deformation. The Pb–Zn mineralization in the Dongmozhazhua area occurs exclusively close to NW–SE-trending reverse fault zones. Microtextural observations reveal that mineralization occurred as veinlets and disseminated blebs in limestone clasts, and as continuous bands and cements in fractured rocks. Cataclastic sulfide grains also can be seen in the matrix of some fault zones. The types of mineralization differ with structural position. The fillings of the ore-bearing veinlets typify the products of hydraulic fracture and both types of mineralization took place concurrently with regional contraction. We consider, therefore, that the ore-bearing fluids in the Dongmozhazhua deposit were concentrated in fault zones during regional compression and that the ore minerals were precipitated during hydraulic fracturing of host rocks. Subsequent fault activity pulverized some pre-existing sulfide material into cataclastic grains in the matrix of a tectonic breccia that developed in the same faults. [ABSTRACT FROM AUTHOR]

The Paleo-Tethyan tectonic evolution of north-central Tibet remains controversial, particularly regarding the nature and extension of associated sutures. The Yushu mélange, located in the junction part of the western Jinshajiang, the southern Jinshajiang and the Ganzi–Litang sutures, is a key area to reveal the Paleo-Tethyan tectonics of this area. This study presents new geochronological and geochemical data for the Zhimenda volcanic suite of the Yushu Mélange. These rocks preserve a record of back-arc magmatism along the northern margin of the North Qiangtang Block. The Zhimenda volcanics are composed of ignimbrite, basalt, and porphyritic tuff intercalated with terrigenous clastic rocks. Zircon 206 Pb/ 238 U ages of the ignimbrites indicate they formed at ~ 254 Ma. The basalts are relatively enriched in large-ion lithophile elements and depleted in high field strength elements. Their high MgO, Ni, and Cr contents, relatively high Sm/Yb and Rb/Nb values, and positive zircon ε Hf (t) and bulk ε Nd (t) values suggest they were derived from the partial melting of a depleted subcontinental lithospheric mantle source metasomatized by hydrous fluids. The Zhimenda basalts are geochemically similar to back-arc basin basalts in the Okinawa Trough. They were erupted related to subduction of the Longmuco–Shuanghu Paleo-Tethyan oceanic plate beneath the North Qiangtang Block. We propose that the Yushu Mélange converges with the Ganzi–Litang Suture Zone to the east, rather than with the Jinshajiang Suture Zone to the southeast, and that a huge Permian trench–arc–back-arc system developed in north-central Tibet. [ABSTRACT FROM AUTHOR]

Carbonate dissolution and deposition in the deep ocean is a critical component of carbon cycle, but detailed pictures of carbonate dynamics below the Carbonate Compensation Depth (CCD) remains poorly understood. In this study, we present a ∼ 420 thousand years record of carbonate content below CCD in IODP Site U1433 at 4.4 km water depth in the South China Sea (SCS). Instead of carbonate-free sediment, we observed that the carbonate content in this deep site could reach as high as 40%. The dissolution-resistant biogenic carbonate, coccoliths, and stable isotope ratio of bulk carbonate were analyzed to trace the carbonate sources. The coccolith assemblage in IODP Site U1433 shows an unrealistic feature of high productivity, which indicates a lateral transport of coccoliths from the northern SCS to the central basin. Coccoliths' contribution to total carbonate was on average 30% and could be as high as ∼80%. Their contribution to carbonate increased at the expense of the dissolution of other biogenic carbonate, such as foraminifera, and decreased with the dilution of other terrestrial carbonate particles. According to the thickness of coccoliths, significant dissolution of coccoliths only happened when the carbonate content dropped below 3%. Marbles from Taiwan, with negative oxygen isotope ratios, and early diagenetic carbonates from carbonate platform nearby, with both negative carbon and oxygen isotope ratios, could be the other important sources besides the marine biogenic carbonate. With help of numerical simulations, we estimated that the lateral transport by turbidity currents could contribute up to 70–90% of the deep-sea sediment in the central basin of SCS. These new findings enrich our knowledge of the carbon fluxes from continental margins to the deep ocean as a key part of the carbon cycle. • Coccoliths in the SCS central basin contribute ∼30% to total carbonates. • Stable isotope ratios of carbonates indicate two mixing lines clearly. • Lateral transport dominates in the SCS deep-sea sediment. [ABSTRACT FROM AUTHOR]

Optical fiber biochemical sensing technology, as a cutting‐edge, multidisciplinary, and universal sensing technology, is gradually becoming the research focus in the field of biochemical sensing. They enjoy distinctive characteristics such as high cost‐effectiveness, flexibility, resistance to electromagnetic interference, and small size and can be used to detect biochemical analytes at ultra‐low concentrations with ultra‐low sample consumption, even when these biochemical analytes are in hard‐to‐reach environments. An aptamer is a DNA or RNA oligonucleotide fragment with a high affinity for the target selected from random sequences. Due to their advantages of simple synthesis, low cost, good stability, good specificity, and strong affinity, they are gradually becoming ideal recognition elements and may replace antibodies as next‐generation target receptors. Therefore, aptamers, as functional materials, are integrated into optical fiber sensors, which are called optical fiber aptasensors, providing new opportunities for the construction of high‐performance and intelligent biochemical sensors. This article aims to review the recent research progress of fiber‐optic aptamer biochemical sensors, with a focus on their sensing mechanisms and applications. Finally, based on the existing deficiencies of fiber‐optic aptamer biochemical sensors and practical requirements, their future development trends are briefly discussed. [ABSTRACT FROM AUTHOR]

The on‐site industrial application of hydratable alumina (HA)‐bonded castables is inhibited by the high hydration rate of HA. In this study, the hydration behavior of HA co‐ground with sheetlike Mg–Al hydrotalcite (MAT) is investigated. The properties of castables bonded with MAT‐bearing HA are systematically assessed. The hydration rate of HA co‐ground MAT decreases as this allows MAT sheets to be effectively inserted into the microcracks of HA particles during grinding, thus decreasing the direct contact area between HA and water. The strength of MAT‐bearing castables (0.5 and 1 wt%) fired at 800°C improved slightly owning to the generation of magnesia–alumina spinel. The mechanical strength of castables fired at 1100 and 1550°C decreased as the MAT content increased owing to an increase in porosity. Based on an analysis of the hydration behavior of HA and the properties of HA‐bonded castables, the optimal MAT/HA weight ratio is approximately 1/10. [ABSTRACT FROM AUTHOR]

Intelligent indoor robotics is expected to rapidly gain importance in crucial areas of our modern society such as at-home health care and factories. Yet, existing mobile robots are limited in their ability to perceive and respond to dynamically evolving complex indoor environments because of their inherently limited sensing and computing resources that are, moreover, traded off against their cruise time and payload. To address these formidable challenges, here we propose intelligent indoor metasurface robotics (I2MR), where all sensing and computing are relegated to a centralized robotic brain endowed with microwave perception; and I2MR's limbs (motorized vehicles, airborne drones, etc.) merely execute the wirelessly received instructions from the brain. The key aspect of our concept is the centralized use of a computation-enabled programmable metasurface that can flexibly mold microwave propagation in the indoor wireless environment, including a sensing and localization modality based on configurational diversity and a communication modality to establish a preferential high-capacity wireless link between the I2MR's brain and limbs. The metasurface-enhanced microwave perception is capable of realizing low-latency and high-resolution three-dimensional imaging of humans, even around corners and behind thick concrete walls, which is the basis for action decisions of the I2MR's brain. I2MR is thus endowed with real-time and full -context awareness of its operating indoor environment. We implement, experimentally, a proof-of-principle demonstration at ∼2.4 GHz, in which I2MR provides health-care assistance to a human inhabitant. The presented strategy opens a new avenue for the conception of smart and wirelessly networked indoor robotics. [ABSTRACT FROM AUTHOR]

Danhong injection (DHI) is a renowned traditional Chinese medicine often used clinically to treat cardiovascular and cerebrovascular diseases. Studies have shown that DHI can significantly alter microRNA (miRNA) expression in the brain tissue. Therefore, exploring specific miRNAs' regulatory mechanisms during treatment with DHI is essential. To investigate DHI's regulatory mechanism on cerebral autophagy in rats with cerebral ischemia-reperfusion injury (CIRI). Rats were randomly divided into the sham, middle cerebral artery occlusion (MCAO) model, and DHI-treatment groups. The extent of brain damage was evaluated using triphenyl tetrazolium chloride and hematoxylin-eosin staining. Hippocampal cell autophagy was observed using transmission electron microscopy. Autophagy-related proteins were analyzed using western blotting. Differentially expressed miRNAs were screened using high-throughput and real-time quantitative reverse transcription PCR. The relationship between miR-132-3p and ATG12 was confirmed using a dual-luciferase assay. The miR-132-3p mimics and inhibitors were transfected into PC12 cells subjected to oxygen-glucose deprivation (OGD) in vitro and MCAO model rats in vivo. DHI significantly altered the miRNA expression profile in rat brain tissues. The pathological changes in the brain tissues were improved, and the autophagic hippocampal cell vehicles were significantly reduced after DHI treatment. miRNA-132-3p, one of the miRNAs with a significantly different expression, was screened. Kyoto Encyclopedia of Genes and Genomes signal pathway analysis showed that its target genes were closely related to autophagy. Western blotting revealed that the p-PI3K, p-AKT, and mTOR expression increased significantly; AMPK, ULK1, ATG12, ATG16L1, and LC3II/I were downregulated in the DHI group. Dual-luciferase reporter gene experiments showed that miRNA-132-3p could target the ATG12 3′-UTR region directly. In vitro, miRNA-132-3p had a protective effect on OGD/R-induced oxidative stress injury in PC12 cells, improving cell viability, and affecting the expression of autophagy pathway-related proteins. In vivo transfection experiments showed that miR-132-3p could regulate ATG12 expression in CIRI rats' lateral brain tissue, affecting the autophagy signaling pathway. miR-132-3p overexpression reduces CIRI-induced autophagy and protects neurons. This study showed that DHI inhibits neuronal autophagy after cerebral ischemia-reperfusion. This may have resulted from miR-132-3p targeting ATG12 and regulating the autophagy signaling pathway protein expression. [Display omitted] • Danhong injection (DHI) is a renowned traditional Chinese medicine. • DHI can significantly change the miRNA expression profile of brain tissue. • DHI can inhibit the production of autophagy-related proteins. • CIRI is a complex pathophysiological process involving multiple mechanisms. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of 3,5-dimethylpyrazole (Me2pz), and CuX in MeOH afforded two trinuclear complexes [Cu( XMe2pz)]3 [ X = I ( 1); Br ( 2)], where the halogenated ligand XMe2pz in 1 and 2 were in-situ formed from the reaction of Me2pz with X-. The crystal structure of 1 was determined by X-ray crystallography. It turned out that it has a classic [Cu3N6] unit. The luminescence properties of 1 and 2 were investigated and the results show that both complexes have high photoluminescence quantum yields of 62 % and 84 % and long lifetimes of 21.7 μs and 30.5 μs, respectively. [ABSTRACT FROM AUTHOR]