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Objective Since the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformationSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotationSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotation. Although extensive paleomagnetic studies have been conducted on the rotation of the central and western parts of the Sichuan-Yunnan rhombic block, less attention has been paid to the rotation of its eastern partSince the collision and compression of the Indo-European continental plates, the Qinghai-Tibetan Plateau has experienced uplift and intra-land deformation. Similarly, the Sichuan-Yunnan block underwent lateral escape and rotation. Although extensive paleomagnetic studies have been conducted on the rotation of the central and western parts of the Sichuan-Yunnan rhombic block, less attention has been paid to the rotation of its eastern part. This study employs fluvial geomorphology, which is highly sensitive to mass rotation, to investigate the rotation and uplift in the Laoyingshan region, situated in the eastern part of the Sichuan-Yunnan block. Methods A 30 m resolution digital elevation model (DEM) was used to identify and analyze 22 basins in the study area. Four geomorphological parameters were examined: local topographic relief ratio, longitudinal profile, normalized steepness index, and basin azimuth. Results (1) According to regional topographic relief, the low-relief area in the Laoyingshan region is mainly located near the Sijia River and the Baizai River on the western side, whereas the high-relief area is mainly found near the Dabai River and the Gongshan River on the eastern side of the Laoyingshan. The relief around the Dabai and Gongshan Rivers was greater than that around the Sijia River on the western side of Laoyingshan. (2) The normalized steepness index in the Laoyingshan area gradually decreased from north to south. The high-value areas are primarily located near Awang and Jinyuan, corresponding to the east and west branches of the Xiaojiang Fault. In contrast, the low-value areas were mainly distributed at the top of the Laoyingshan and south of the Baozai River in the study area. (3) The results of the river longitudinal profile indicated that the average surface uplift of the area was approximately 358 m. (4) Based on the results of the watershed azimuth angle, the Laoyingshan area underwent a counterclockwise rotation of approximately 15°. Conclusion The analysis suggests that since the Late Miocene, the western region of the Sichuan-Yunnan block, located west of the Yuanmou Fault, has experienced fewer effects from strike-slip faults and has predominantly undergone clockwise rotation. Conversely, the eastern region of the Sichuan-Yunnan block, influenced by strike-slip faults, underwent counterclockwise rotation with differential uplift. [ Significance] The fluvial geomorphological index outlines the tectonic rotation of the eastern Sichuan-Yunnan block.

Due to the weakened shear stiffness of trapezoidal corrugated steel webs (TCSWs), it is necessary to account for shear deformation in calculating the total deformation for girders with TCSWs. Most of the existing research on the deformation of girders with TCSWs has mainly concentrated on prismatic cases. However, there has been a lack of research on the deformation analysis of tapered girders with TCSWs. Based on theoretical derivations, experiments, and finite-element (FE) simulations, this study investigated the deformation of a tapered box girder with TCSWs, taking into account the combined influences of shear deformation and the Resal effect. The study found that the contribution of shear deformation to total deformation in a cantilever tapered test girder with TCSWs is significant, representing 10.88% at the free end, increasing to 14.19% at the midspan, and reaching a substantial 35.31% near the fixed end. Furthermore, the study revealed that the bending moment can also induce additional shear deformation on both the TCSWs and the inclined concrete bottom slab due to the Resal effect. Importantly, the shear deformation induced by the bending moment accounts for a substantial proportion of the total shear deformation in sections that experience higher bending moments. Therefore, the basic assumption, which applies to prismatic girders, that the TCSWs solely bear all the shear forces and that shear deformation is entirely induced by shear force on the web, does not apply to tapered girders. Consequently, the study proposed a theoretical formula that considers the additional shear force on the bottom slab and TCSWs induced by the bending moment for predicting the deformation of tapered girders with TCSWs. This method yielded more accurate deformation predictions for tapered girders with TCSWs and can serve as a solid theoretical foundation for structural deformation analysis. [ABSTRACT FROM AUTHOR]

As a key element in quantum repeaters, entanglement swapping establishes entanglement between two independent entangled states. Besides entanglement, quantum steering has been identified as an essential quantum resource and has broad applications in quantum communication. Although entanglement swapping has been realized experimentally, quantum steering swapping still remains a challenge since the condition of quantum steering is stronger than that of entanglement. In this article, quantum steering swapping between a three‐mode and a two‐mode Gaussian entangled state in a lossy channel is demonstrated. By choosing the optimum gain in the classical channel that corresponds to the maximum transmission distance, the one‐way and two‐way steerabilities in a new three‐mode Gaussian state located in distant nodes are achieved. The obtained collective steerability from two users to one user has potential application in quantum secret sharing. The results make a crucial step toward applications of quantum steering in asymmetric quantum information processing. [ABSTRACT FROM AUTHOR]

Target misalignment can cause beam pointing deviations and degradation of sidelobe performance. In order to eliminate the effect of target misalignment, we formulate the jamming sub-space recovery problem as a linearly modified atomic norm-based optimization. Then, we develop a deep-unfolding network based on the alternating direction method of multipliers (ADMM), which effectively improves the applicability and efficiency of the algorithm. By using the back-propagation process of deep-unfolding networks, the proposed method could optimize the hyper-parameters in the original atomic norm. This feature enables the adaptive beamformer to adjust its weight according to the observed data. Specifically, the proposed method could determine the optimal hyper-parameters under different interference noise matrix conditions. Simulation results demonstrate that the proposed network could reduce computational cost and achieve near-optimal performance with low complexity. [ABSTRACT FROM AUTHOR]

Recently, deep unfolding networks have been widely used in direction of arrival (DOA) estimation because of their improved estimation accuracy and reduced computational cost. However, few have considered the existence of a nested array (NA) with off-grid DOA estimation. In this study, we present a deep sparse Bayesian learning (DSBL) network to solve this problem. We first establish the signal model for off-grid DOA with NA. Then, we transform the array output into a real domain for neural networks. Finally, we construct and train the DSBL network to determine the on-grid spatial spectrum and off-grid value, where the loss function is calculated using reconstruction error and the sparsity of network output, and the layers correspond to the steps of the sparse Bayesian learning algorithm. We demonstrate that the DSBL network can achieve better generalization ability without training labels and large-scale training data. The simulation results validate the effectiveness of the DSBL network when compared with those of existing methods. [ABSTRACT FROM AUTHOR]

Agroforestry systems are considered effective methods of carbon sequestration. In these systems, most of the carbon is stored in the soil, and the pattern of tree planting can influence the spatial distribution of organic matter input into the soil. However, limited information is available about the extent of this influence. In this study, the horizontal and vertical distributions of soil organic carbon (SOC) and labile fractions were investigated in four planting systems: a pure poplar (Populus deltoides cv. "35") planting system, a wide-row (14 m spacing) poplar and wheat (Triticum aestivum L.) agroforestry system, a narrow-row (7 m spacing) poplar and wheat agroforestry system, and a pure wheat field. The results showed that although the poplar system had the highest vegetation biomass (147.50 t ha−1), the agroforestry systems overall had higher SOC contents than the pure poplar system and wheat fields. Especially in the wide-row agroforestry system, the SOC, readily oxidizable carbon, and dissolved organic carbon contents were, respectively, 25.3%, 42.4%, and 99.3% higher than those of the pure poplar system and 60.3%, 148.7%, and 6.3% higher than those of the wheat field in a 1 m soil profile, and it also had the highest fine root biomass. However, the microbial biomass carbon content was highest in the pure poplar system. The SOC of the three poplar planting systems was spatially heterogeneous, with the highest values occurring at 1.5 m in the narrow-row systems and within the tree rows in the wide-row system, similar to the distribution of fine root biomass. Additionally, we found that the larger the diameter at the breast height of the trees, the greater their positive effect on SOC at greater distances. [ABSTRACT FROM AUTHOR]

Remote state preparation enables one to prepare and manipulate quantum state non‐locally. As an essential quantum resource, optical cat state is usually prepared locally by subtracting photons from a squeezed vacuum state. For remote quantum information processing, it is essential to prepare and manipulate optical cat states remotely based on Gaussian entanglement, which remains a challenge. Here, experimental preparation of optical cat states based on a remotely distributed two‐mode Gaussian entangled state in a lossy channel is presented. By performing photon subtraction and homodyne projective measurement at Alice's station, an optical cat state is prepared remotely at Bob's station. Furthermore, the prepared cat state is rotated by changing Alice's measurement basis of homodyne detection, which demonstrates the remote manipulation of it. By distributing two modes of the two‐mode Gaussian entangled state in lossy channels, it is demonstrated that the remotely prepared cat state can tolerate much more loss in Alice's channel than that in Bob's channel. It is also shown that cat states with amplitudes larger than 2 can be prepared by increasing the squeezing level and subtracting photon numbers. The results make a crucial step toward remote hybrid quantum information processing involving discrete‐ and continuous‐variable techniques. [ABSTRACT FROM AUTHOR]

Precast segmental construction can shorten the construction time of the bridge and reduce the impacts on traffic and environment. Thus, this approach has been widely used in many countries. The relevant literature suggests that in the existing segmental precast bridges, nearly all of the centerlines of the girders are aligned with the centerline of the bridge piers. This paper introduces a wide urban viaduct comprising twin separate box girder cells using segmental prefabrication. To save space under the bridge, the bridge has only one row of piers and long cantilever crossbeams are set at the top of each pier. Additionally, the centerline of the girder and the centerline of the pier do not overlap. To prevent eccentric loading and improve the construction speed, two bridge erection gantries are used for synchronous construction. This study is a pioneering attempt at bridge construction with a precast segmental twin‐deck box girder bridge simultaneously erected with double gantries. To investigate the stress state of the whole system (crossbeam, gantries, and box girder segments) during construction and demonstrate the feasibility of the construction method, a real bridge was used. The test results provide a reference for the design and construction of similar projects. [ABSTRACT FROM AUTHOR]

The Aizhai Bridge is the longest suspension bridge crossing a canyon in the world. A novel pylon–girder detached suspension structure was first adopted in the design of the Aizhai Bridge, which provided a new concept for the design of suspension bridges. Moreover, the application of a high-performance carbon fiber rock anchor system in the bridge provided a new method for applying high-performance carbon fiber materials in engineering structures. In addition, the construction method of the girder-conveying track cable technique proposed for the Aizhai Bridge successfully solved the problem of the erection of the stiffening girders of long-span suspension bridges in mountainous areas. This study mainly introduces the design method, the application of new materials, and the advanced construction technologies of the Aizhai Bridge. [ABSTRACT FROM AUTHOR]

Sirtuin 1 (SIRT1) overexpression significantly inhibits lipid deposition during yak intramuscular preadipocyte (YIMA) differentiation; however, the regulatory mechanism remains unknown. We elucidated the role of SIRT1 in YIMA differentiation using lentivirus-mediated downregulation technology and conducted mRNA-seq and ChIP-seq assays using H3K9ac antibodies after SIRT1 overexpression in order to reveal SIRT1 targets during YIMA adipogenesis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed in order to identify the functional annotation of common genes. In addition, a potential target of SIRT1 was selected to verify its effects on the differentiation and proliferation of YIMAs. SIRT1 interfered with lipid deposition and promoted YIMA differentiation. In total, 143,518 specific peaks were identified after SIRT1 overexpression, where genes associated with downregulation peaks were enriched in transcription, gene expression, lipid-related processes, and classical lipid-related pathways. The H3K9ac signal in the whole genome promoter region (2 kb upstream and downstream of the transcription start site (TSS)) was weakened, and the peaks were distributed across all gene functional regions. Genes that lost signals in their TSS region or gene body region were enriched in both biological processes and pathways associated with lipogenesis. The ChIP-seq results revealed 714 common differential genes in mRNA-seq, which were enriched in "MAPK signaling", "lipid and atherosclerosis", "mTOR signaling", and "FoxO signaling" pathways. A total of 445 genes were downregulated in both their H3K9ac signals and mRNA expression, and one of their most significantly enriched pathways was FoxO signaling. Nine genes (FBP2, FPGT, HSD17B11, KCNJ15, MAP3K20, SLC5A3, TRIM23, ZCCHC10, and ZMYM1) lost the H3K9ac signal in their TSS regions and had low mRNA expression, and three genes (KCNJ15, TGM3, and TRIM54) had low expression but lost their H3K9ac signal in the gene body region. The interference of TRIM23 significantly inhibited fat deposition during preadipocyte differentiation and promoted cell proliferation by increasing S-phase cell numbers. The present study provides new insights into the molecular mechanism of intramuscular fat content deposition and the epigenetic role of SIRT1 in adipocyte differentiation. [ABSTRACT FROM AUTHOR]

The cat state, known as the superposition of coherent states, has broad applications in quantum computation and quantum metrology. Increasing the number of optical cat states is crucial to implement complex quantum information tasks based on them. Here, two optical cat states are prepared simultaneously based on a nondegenerate optical parametric amplifier. By subtracting one photon from each of two squeezed vacuum states, two odd cat states with orthogonal superposition direction in phase space are prepared simultaneously, which have similar fidelity of 60% and amplitude of 1.2. Compared with the traditional method to generate two odd optical cat states based on two degenerate optical parametric amplifiers, only one nondegenerate optical parametric amplifier is applied in this experiment, which saves half of the quantum resources of nonlinear cavities. The presented results make a step toward preparing the four‐component cat state, which has potential applications in fault‐tolerant quantum computation. [ABSTRACT FROM AUTHOR]

Parameter estimation is significant to prediction and estimation in the field of radar clutter characteristics. Therefore, it is necessary to study the problem of parameter estimation. The K-distribution is a commonly used model in sea clutter, which is a two-parameter model with shape parameters and scale parameters. The value of the shape parameters should be greater than 0. Moment estimation is usually used to estimate the parameters of the K-distribution. It overcomes the disadvantage of large computation compared with the maximum likelihood estimation method. However, the moment estimation usually uses two different order origin moments to solve the parameters. The joint solution of different order will cause large calculation errors, and sometimes the shape parameter is estimated to be less than 0. In the origin moment expression, the order k can be regarded as a continuous variable. By calculating the relationship between the k-order origin moment and its derivative, a parameter estimation method based on the origin moment derivative is proposed. The estimation efficiency and accuracy are compared with some moment estimation methods. Both simulation data and measured clutter data show that this method can achieve 100% estimation efficiency, can obtain higher estimation accuracy, and can also avoid the situation where the estimated value of the shape parameter is less than 0. Using the same idea to estimate the parameters in the two-parameter models, log–normal and Weibull distribution, we can also obtain the parameters with higher estimation accuracy. The experiments show that the higher-order origin moments are sensitive to the data, and the lower-order moments should be selected as far as possible. By selecting the appropriate order k, we can obtain ideal estimation parameters. [ABSTRACT FROM AUTHOR]

This paper analyzes the shear behavior of prismatic and tapered continuous beams with corrugated steel webs (CSWs) under different external prestressing tendon layouts. For girder bridges with CSWs, the existing design specifications consider only the shear force caused by the external prestressing force when calculating the shear stress of CSWs under the external prestressing tendons. However, in a tapered continuous beam with CSWs, in addition to the shear force caused by the prestressing force, the prestressing bending moment and the horizontal component of prestressing can also induce additional shear stress, which results in a redistribution of the shear stress on the section. This finding has not been reported previously. Then, the reasons for the shear behavior differences of tapered and prismatic continuous beams with CSWs under external prestressing tendons are explored. The study reveals the factors affecting the distribution of shear stress on indeterminate static beams with CSWs under external prestressing and proves that the traditional method used for predicting the shear stress on CSWs is not applicable to tapered cases. In addition, it is found that the direction of the internal forces and moments also affects the shear-bearing ratios of CSWs and concrete slabs. Consequently, a unified analytical formula is proposed for calculating the shear stresses of the CSWs induced by external prestressing, and it can be applied to both tapered and prismatic continuous beams with CSWs under external prestressing tendons. [ABSTRACT FROM AUTHOR]