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Climate warming accelerates permafrost thawing, causing warming‐driven disasters like ground collapse and retrogressive thaw slump (RTS). These phenomena, involving intricate multiphysics interactions, phase transitions, nonlinear mechanical responses, and fluid‐like deformations, and pose increasing risks to geo‐infrastructures in cold regions. This study develops a thermo‐hydro‐mechanical (THM) coupled single‐point three‐phase material point method (MPM) to simulate the time‐dependent phase transition and large deformation behavior arising from the thawing or freezing of ice/water in porous media. The mathematical framework is established based on the multiphase mixture theory in which the ice phase is treated as a solid constituent playing the role of skeleton together with soil grains. The additional strength due to ice cementation is characterized via an ice saturation‐dependent Mohr–Coulomb model. The coupled formulations are solved using a fractional‐step‐based semi‐implicit integration algorithm, which can offer both satisfactory numerical stability and computational efficiency when dealing with nearly incompressible fluids and extremely low permeability conditions in frozen porous media. Two hydro‐thermal coupling cases, that is, frozen inclusion thaw and Talik closure/opening, are first benchmarked to show the method can correctly simulate both conduction‐ and convection‐dominated thermal regimes in frozen porous systems. The fully THM responses are further validated by simulating a 1D thaw consolidation and a 2D rock freezing example. Good agreements with experimental results are achieved, and the impact of hydro‐thermal variations on the mechanical responses, including thaw settlement and frost heave, are successfully captured. Finally, the predictive capability of the multiphysics MPM framework in simulating thawing‐triggered large deformation and failure is demonstrated by modeling an RTS and the settlement of a strip footing on thawing ground. [ABSTRACT FROM AUTHOR]

Direct current microgrid (DCMG) clusters are gaining popularity in power systems due to their simplicity and high efficiency. However, DCMG clusters are susceptible to minor disturbances due to low system inertia. This paper proposes a method to enhance the small‐signal stability of a DCMG cluster by optimizing the main control parameters of the system. This paper presents a small‐signal state‐space model of a DCMG cluster system at the system level, considering a multi‐bus network topology. Then, the control parameters that significantly affect the small‐signal stability of the DCMG are selected using the participation factor method. To enhance the system damping, the Pareto‐optimal frontier of the bi‐objective problem was determined using the elite non‐dominated sorting genetic algorithm (NSGA‐II). The optimal compromise is determined by using the fuzzy membership function method to extract it from the generated Pareto optimal front. The proposed method has been verified on a three‐sub DCMG test system with droop control. [ABSTRACT FROM AUTHOR]

Single-event burnout and single-event leakage current (SELC) in silicon carbide (SiC) power devices induced by heavy ions severely limit their space application, and the underlying mechanism is still unclear. One fundamental problem is lack of high-resolution characterization of radiation damage in the irradiated SiC power devices, which is a crucial indicator of the related mechanism. In this Letter, high-resolution transmission electron microscopy (TEM) was used to characterize the radiation damage in the 1437.6 MeV 181Ta-irradiated SiC junction barrier Schottky diode under 200 V. The amorphous radiation damage with about 52 nm in diameter and 121 nm in length at the Schottky metal (Ti)–semiconductor (SiC) interface was observed. More importantly, in the damage site the atomic mixing of Ti, Si, and C was identified by electron energy loss spectroscopy and high-angle annular dark-field scanning TEM. It indicates that the melting of the Ti–SiC interface induced by localized Joule's heating is responsible for the amorphization and the possible formation of titanium silicide, titanium carbide, or ternary phases. The mushroom-like hillock in the Ti layer can be attributed to Rayleigh–Taylor instability, as another evidence for ever-happened localized melting near the Schottky interface. These modifications at nanoscale in turn cause localized degradation of the Schottky contact, resulting in permanent increase in leakage current. This experimental study provides very valuable clues for a thorough understanding of the SELC mechanism in SiC diodes. [ABSTRACT FROM AUTHOR]

Massive multiplayer online role-playing games (MMORPG) have been becoming one of the most popular and exciting online games. In recent years, a cheating phenomenon called real money trading (RMT) has arisen and damaged the fantasy world in many ways. RMT is the sale of in-game items, currency, or even characters to earn real money, breaking the balance of the game economy ecosystem and damaging the game experience. Therefore, some studies have emerged to address the problem of RMT detection. However, they cannot well handle the label uncertainty problem in practice, where there are only labeled RMT samples (positive samples) and unlabeled samples, which could either be RMT samples or normal transactions (negative samples). Meanwhile, the trading relationship between RMTers is modeled in a simple way, leading to some normal transactions being falsely classified as RMT. In this article, we propose PU-Detector, a novel framework based on PU learning (learning from positive and unlabeled data) for RMT detection, considering the fact that there are only labeled RMT samples and other unlabeled transactions. We first automatically estimate the likelihood of one transaction being RMT by developing an improved PU learning method and proposing an assessment rule. Sequentially, we use the estimated likelihood as edge weight to construct a trading graph to learn trader representation. Then, with the trader representations and basic trading features, we detect RMT samples by the improved PU learning method. PU-Detector is evaluated on a large-scale real world dataset consisting of 33,809,956 transaction logs generated by 43,217 unique players. Compared with other approaches, it achieves the state-of-the-art performance and demonstrates its advantages in detecting underlying RMT samples. [ABSTRACT FROM AUTHOR]

The flapping wing rotor (FWR) is a novel aerial vehicle that combines the aerodynamic benefits of both a flapping wing and a rotary wing. By utilizing the passive rotation effect resulting from the flexible deformation of the center symmetric flapping wing, the FWR can enhance its lift force. However, previous research has neglected to explore the mechanism behind the flapping-rotation motion of a flyable FWR, which elucidates its lift advantage compared to conventional flapping motion. Additionally, the impact of varying wing number on the flapping-rotation motion and performance of the FWR has not been taken into consideration. Therefore, it is imperative to conduct an experimental analysis to ascertain the impact of flapping-rotation decomposition and varying wing quantities on FWR. In this study, our prior vehicle design, which exhibited consistent stable hovering and maneuvering capabilities, is employed to construct the flapping wing rotor experiment system. Through this unique experimental system, the effects of flapping-rotation decomposition and different wing quantities on FWR are individually investigated. Additionally, computational fluid dynamics simulation is utilized as an auxiliary and supplementary approach to analyze the aerodynamic characteristics of the flapping-rotation motion. The result proves that the stable flapping-rotation motion does produce a more significant lift increase than the normal flapping motions. Under the premise of stable flapping-rotation motion, more wings will not only produce more lift but also require more driving power. The interactions between the wings also affect the flapping-rotation motion. [ABSTRACT FROM AUTHOR]

This letter presents a design method of resistance reactance hybrid continuous power amplifier based on reconfigurable devices and CG2H40010F. The power amplifier combines resistive‐reactive inverse F‐class power amplifier (RRIFPA), resistive‐reactive J‐class power amplifier (RRJPA), and resistive‐reactive F class power amplifier (RRFPA). We utilize the principle of low‐pass filters to control the impedance of multi‐frequency harmonics, and use the reconfigurable device SMP1345‐079LF to expand the bandwidth of the power amplifier. This article designs and produces a 1–4 GHz broadband power amplifier. The simulation and measurement results show that within the entire frequency range of 1–4 GHz, the Drain efficiency is between 53.6 and 72.1% $ \% $, the output power is between 40.1 and 42.6 dBm, the gain is between 10.1 and 12.6 dB, and the relative bandwidth is up to 120% $ \% $. [ABSTRACT FROM AUTHOR]

Phthalic plasticizer plays an important role in processing and manufacturing one of the universal polymer materials, poly (vinyl chloride) (PVC), which has been widely applied in every aspect of our lives. However, there still exists the intrinsic problem in migration resistance of phthalic plasticizer in long‐term use. In this work, we take a facile and convenient approach by incorporating commercial graphene oxide (GO) into PVC matrix to prepare polyvinyl chloride/graphene oxide (PVC/GO) composites, forming a sheet structure for improving the migration resistance of phthalic plasticizer. The advantages of GO that has abundant oxygen‐containing groups on its surface, including carboxyl groups at the sheet edges, epoxy groups, and hydroxyl groups on its basal planes. Especially, these oxygen‐containing groups in GO are beneficial to blend with long molecular chain of PVC and the sheet structure of GO can prevent phthalic plasticizer migrating from interior PVC. Addition of GO not only effectively enhanced the mechanical properties of PVC/GO composites but also improve their migration resistance due to the sheet structure. This strategy provides an attractive way to solve the problem of migration of plasticizer with simple incorporation GO into the matrix of PVC, reinforcing the composite properties and broadening its applied fields. [ABSTRACT FROM AUTHOR]

Aero-optic imaging deviation research is carried out for infrared-guided vehicle with cone-head side window, with a focus on the propagation characteristics of light in an aero-optic flow field. When the light entering the aero-optic flow field from the free-stream should be close to the normal, numerous data indicate that the light is refracted away from the normal. This paper divides the aero-optic flow field into two parts and uses the gas density distribution in the aero-optic flow field to propose the hypothesis that there are two modes of refraction when light propagates through the flow field. The results show that light propagates from the optically denser medium to the optically thinner medium after passing through the shock wave and eventually leads to refraction away from the normal when the light enters the aero-optic flow field. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive review of deep learning applications in the video game industry, focusing on how these techniques can be utilized in game development, experience, and operation. As relying on computation techniques, the game world can be viewed as an integration of various complex data. This examines the use of deep learning in processing various types of game data. The paper classifies the game data into asset data, interaction data, and player data, according to their utilization in game development, experience, and operation, respectively. Specifically, this paper discusses deep learning applications in generating asset data such as object images, 3D scenes, avatar models, and facial animations; enhancing interaction data through improved text-based conversations and decision-making behaviors; and analyzing player data for cheat detection and match-making purposes. Although this review may not cover all existing applications of deep learning, it aims to provide a thorough presentation of the current state of deep learning in the gaming industry and its potential to revolutionize game production by reducing costs and improving the overall player experience. [ABSTRACT FROM AUTHOR]

Catapult-assisted takeoff is the initiation of flight missions for carrier-based aircrafts. Ensuring the safety of aircrafts during catapult-assisted takeoff requires a thorough analysis of their motion characteristics. In this paper, a rigid–flexible coupling model using the Finite Element Method and Multibody Dynamics (FEM-MBD) approach is developed to simulate the aircraft catapult process. This model encompasses the aircraft frame, landing gear, carrier deck, and catapult launch system. Firstly, reasonable assumptions were made for the dynamic modeling of catapult-assisted takeoff. An enhanced plasticity algorithm that includes transverse shear effects was employed to simulate the tensioning and release processes of the holdback system. Additionally, the forces applied by the launch bar and holdback bar, nonlinear aerodynamics loads, shock absorbers, and tires were introduced. Finally, a comparative analysis was conducted to assess the influence of different launch bar angles and holdback bar fracture stain on the aircraft's attitude and landing gear dynamics during the catapult process. The proposed rigid–flexible coupling dynamics model enables an effective analysis of the dynamic behavior throughout the entire catapult process, including both the holdback bar tensioning and release, takeoff taxing, and extension of the nose landing gear phases. The results show that higher launch bar angle increase the load and extension of the nose landing gear and cause pronounced fluctuations in the aircraft's pitch attitude. Additionally, the holdback bar fracture strain has a significant impact on the pitch angle during the first second of the aircraft catapult process, with greater holdback bar fracture strain resulting in larger pitch angle variations. [ABSTRACT FROM AUTHOR]

Non-cooperative target tracking technology has significant applications in the field of ocean, serving both military and civilian purposes. The emerging underwater acoustic sensor networks (UASNs) have great potential for target tracking, but face challenges that include energy constraints, stratification effect, variable environment, and measurement outliers. To address these issues, a non-cooperative target tracking method based on UASNs is proposed in this paper. First, a mutual information (MI) function is established with the predicted target state and the received signal strength. Then, an MI-based active tracking node selection method is designed to reduce energy consumption and ensure tracking accuracy. After identifying active tracking nodes, a ray tracking method is used to calculate the distances under stratification effect. Subsequently, a robust and adaptive tracking algorithm is designed based on interactive multiple models assisted unscented Kalman filter to achieve accurate tracking, in which the equivalent noise covariance is utilized to change measurement noise adaptively, and a detector is implemented to detect and correct measurement outliers. The motion model transition probability is also adaptively adjusted based on the corrected data. Finally, the simulation and experimental results verify the feasibility and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In recent years, with the development of intelligent technology, rotorcrafts have been widely used in unmanned collaborative missions due to their excellent maneuverability and vertical flight capability. However, the flight process of rotorcrafts generates a noticeable induced flow that affects the flight safety of surrounding aircrafts. In the current research on the aerodynamic interference of multiple rotorcrafts, scholars are focusing on the effects of the upper rotor on lower rotors, while ignoring the induced influence of lower rotors. In this research, the detached eddy simulation was used to analyze the numerical and flow characteristics of an upper small-ducted-rotor (SDR) disturbed by a large-rotor (LR). The Q-criterion and power spectrum density method were employed to analyze the wake vortex evolution characteristics of the SDR. The results indicate that the thrust loss of the duct is significantly positively correlated with the rotational speeds of both SDR and LR, whereas the thrust loss of the rotor is only associated with the rotational speed of LR. The thrust loss of the duct is significantly greater than that of the rotor, primarily due to the disruption of attachment vortices and the generation of new shear-layer shedding vortices. Wake analysis reveals that the disturbance from LR simultaneously enhances both the kinetic and turbulent kinetic energy around SD, resulting in the discovery of multiple energy peak frequencies in the near- and mid-field distinct from the blade-passing frequency. This research helps analyze rotorcrafts' flight safety during the collaborative processes. [ABSTRACT FROM AUTHOR]

Adopting only a small amount of azobenzene molecular to design liquid crystal photo‐responsive materials capable of quick response and flexible adjustability is in high demand but is challenging. Herein, azobenzenemolecules into polyurethane elastomer containing crystalline structure for preparing azobenzene liquid‐crystal elastomers (ALCEs) are demonstrated and this phenomenon of the synergistic effects between liquid crystal and crystalline phase is discovered. The key point of the work is that the synthetic ALCEs can utilize the reversible isomerism capability of azobenzene molecules under light irradiation, which can pry the motion of the macromolecular crystalline region in system to realize the large macroscopic deformation of the photo‐responsive behavior. Obviously, the ALCEs sample containing azobenzene molecule and polyethylene glycol crystallization can quickly bend, illuminated by ultraviolet light and rapidly straighten under green light. Under the same ultraviolet irradiation, the bending speed, final bending angle, recovery rate and recovery ratio of ALCEs are larger than that of ALCEs without any crystalline structure. This ALCEs based on the synergistic effects between liquid crystal and crystalline phase can break through the current dilemma that the application of traditional azobenzene photo‐responsive materials is limited by their concentration, greatly expanding the design thought and their scope of application. [ABSTRACT FROM AUTHOR]

Background: Checkpoint-based immunotherapy has failed to elicit responses in the majority of patients with pancreatic cancer. In our study, we aimed to identify the role of a novel immune checkpoint molecule V-set Ig domain-containing 4 (VSIG4) in pancreatic ductal adenocarcinoma (PDAC). Methods: Online datasets and tissue microarray (TMA) were utilized to analyze the expression level of VSIG4 and its correlation with clinical parameters in PDAC. CCK8, transwell assay and wound healing assay were applied to explore the function of VSIG4 in vitro. Subcutaneous, orthotopic xenograft and liver metastasis model was established to explore the function of VSIG4 in vivo. TMA analysis and chemotaxis assay were conducted to uncover the effect of VSIG4 on immune infiltration. Histone acetyltransferase (HAT) inhibitors and si-RNA were applied to investigate factors that regulate the expression of VSIG4. Results: Both mRNA and protein levels of VSIG4 were higher in PDAC than normal pancreas in TCGA, GEO, HPA datasets and our TMA. VSIG4 showed positive correlations with tumor size, T classification and liver metastasis. Patients with higher VSIG4 expression were related to poorer prognosis. VSIG4 knockdown impaired the proliferation and migration ability of pancreatic cancer cells both in vitro and in vivo. Bioinformatics study showed positive correlation between VSIG4 and infiltration of neutrophil and tumor-associated macrophages (TAMs) in PDAC, and it inhibited the secretion of cytokines. According to our TMA panel, high expression of VSIG4 was correlated with fewer infiltration of CD8+ T cells. Chemotaxis assay also showed knockdown of VSIG4 increased the recruitment of total T cells and CD8+ T cells. HAT inhibitors and knockdown of STAT1 led to decreased expression of VSIG4. Conclusions: Our data indicate that VSIG4 contributes to cell proliferation, migration and resistance to immune attack, thus identified as a promising target for PDAC treatment with good prognostic value. [ABSTRACT FROM AUTHOR]

When the aircraft is moving at high speed in the atmosphere, aero-optical imaging deviation will appear due to the influence of aero-optical effect. In order to achieve real-time compensation during the flight of the aircraft, it is necessary to analyze and predict the obtained imaging deviation data. In order to improve the search speed and accuracy of the prediction algorithm and the ability to jump out of local optimum, in this paper, an improved sparrow search algorithm optimized extreme learning machine (ISSA-ELM) neural network model is proposed to predict the aero-optical imagine deviation. Finally, the performance of ISSA-ELM, ELM neural network and SSA-ELM neural network was tested. The results showed that compared with ELM and SSA-ELM algorithms, the convergence speed of ISSA-ELM was significantly enhanced, and the accuracy of data prediction was also significantly improved. [ABSTRACT FROM AUTHOR]

SensorCraft is an intelligence, surveillance, and reconnaissance (ISR) system that integrates unmanned flight platforms and airborne antenna arrays. Under gust loads, the high–aspect–ratio, light–wing structure of SensorCraft has considerable bending and torsion deformation, affecting the flight performance of unmanned flight platforms and leading to the loss of antenna arrays' electromagnetic performance. Taking SensorCraft as the background, a wing conformal antenna array was designed, an aircraft model with a passive wingtip device was established, a control law was developed by the LQG/LTR method, and a gust alleviation active–passive combined control method of a "LQG/LTR active controller + passive wingtip device" was proposed. By constructing an unsteady aerodynamic reduced–order model (ROM) based on the Volterra series and a conformal array pattern fast method based on the modal form, the effectiveness of the gust alleviation active–passive combined control method on the aircraft platform and antenna array was analyzed. The results show that structural deformation of the wing conformal antenna leads to changes in the main lobe gain, beam direction, and sidelobe level. The active–passive gust alleviation method has obvious advantages. Compared with the LQG/LTR active gust alleviation method, the peak value of wingtip displacement is reduced by 15.6%, and the peak value of the gain loss is reduced by 0.72 dB, which is conducive to better performance of the airborne conformal antenna array. [ABSTRACT FROM AUTHOR]

Investigating the genetic diversity and population structure is important in conserving narrowly distributed plants. In this study, 90 Clematis acerifolia (C. acerifolia) plants belonging to nine populations were collected from the Taihang Mountains in Beijing, Hebei, and Henan. Twenty-nine simple sequence repeats (SSR) markers developed based on RAD-seq data were used to analyze the genetic diversity and population structure of C. acerifolia. The mean PIC value for all markers was 0.2910, indicating all SSR markers showed a moderate degree of polymorphism. The expected heterozygosity of the whole populations was 0.3483, indicating the genetic diversity of both C. acerifolia var. elobata and C. acerifolia were low. The expected heterozygosity of C. acerifolia var. elobata (He = 0.2800) was higher than that of C. acerifolia (He = 0.2614). Genetic structure analysis and principal coordinate analysis demonstrated that C. acerifolia and C. acerifolia var. elobata showed great genetic differences. Molecular variance analysis (AMOVA) demonstrated that within-population genetic variation (68.31%) was the main contributor to the variation of the C. acerifolia populations. Conclusively, C. acerifolia var. elobata had higher genetic diversity than C. acerifolia, and there are significant genetic differences between C. acerifolia and C. acerifolia var. elobata, and small genetic variations within the C. acerifolia populations. Our results provide a scientific and rational basis for the conservation of C. acerifolia and provide a reference for the conservation of other cliff plants. [ABSTRACT FROM AUTHOR]

This research suggests a methodology to optimize Elman neural network based on improved slime mould algorithm (ISMA) to anticipate the aero optical imaging deviation. The improved Tent chaotic sequence is added to the SMA to initialize the population to accelerate the algorithm's speed of convergence. Additionally, an improved random opposition-based learning was added to further enhance the algorithm's performance in addressing problems that the SMA has such as weak convergence ability in the late iteration and an easy tendency to fall into local optimization in the optimization process when solving the optimization problem. Finally, the algorithm model is compared to the Elman neural network and the SMA optimization Elman neural network model. The three models are assessed using four evaluation indicators, and the findings demonstrate that the ISMA optimization model can anticipate the aero optical imaging deviation in an accurate way. [ABSTRACT FROM AUTHOR]

To cope with the increasing demands of the application of high step-up DC-DC conversion, such as the absorption of renewable energy,electric vehicles and aerospace,a high step-up DC-DC converter based on three-winding coupled inductor with low voltage stress was proposed by utilizing magnetic coupling technology to design three-winding coupled inductor and mixing with switched capacitor structure. The converter has the merits of high voltage gain,low voltage stress of devices and soft switching of all diodes. Each operational mode was analyzed,the voltage conversion gain was deduced,the voltage and average current stresses of all devices were obtained. Finally,a prototype in the condition of 120 W was produced to achieve voltage conversion of 386/23.8 V DC-DC and verify the theoretical analysis and the feasibility of the proposed converter. [ABSTRACT FROM AUTHOR]

Aero-optical imaging deviation is a kind of optical effect, aiming at a conical aircraft. This paper analyzes the influence of the aircraft on the imaging deviation with the change of altitude and line-of-sight angle. In this paper, the relationships between imaging deviation and altitude as well as line-of-sight angle are analyzed, and the coupling relationship between altitude and line-of-sight angle is studied. We give the imaging deviation results of 5°–75° line-of-sight angle. The analysis shows that when the line-of-sight angle is in the range of 5°–35°, the imaging deviation is more sensitive, while the line-of-sight angle is in the range of 35°–75°, the imaging deviation is relatively flat, and the imaging deviation does not gradually decrease with the increase of line-of-sight angle, but there is a turning point in the middle of 5°–75°. The imaging deviation decreases first and then increases, and the turning point of line-of-sight angle is closely related to height. [ABSTRACT FROM AUTHOR]

Background: The short-term outcome and long-term survival of pancreaticoduodenectomy with additional para-aortic dissection (PAD) for patients with resectable pancreatic cancer remain obscure. Patients and Methods: Consecutive patients who underwent radical pancreaticoduodenectomy for resectable pancreatic cancer in a single high-volume center during a 7-year period were included retrospectively. Both short- and long-term effects of PAD were compared between the PAD group and the no PAD group. Then, the PAD group was divided into the non-metastatic para-aortic lymph node (PALN−) group and the metastatic PALN (PALN+) group to further analyze the prognosis of PALN+. Results: Of the 909 included patients, 280 (30.8%) underwent PAD during pancreaticoduodenectomy. The PAD group had a higher rate of intra-abdominal infection compared with the no PAD group (28.6% vs. 20.7%, P = 0.009) but no differences were found in the incidence of other complications. The overall survival (OS) and recurrence-free survival (RFS) were also comparable between the two groups. Subgroup analysis showed that patients with PALN+ had a worse OS than patients in the PALN− group (median of 14 vs. 20 months, P = 0.048). Multivariate Cox regression analysis further revealed that PALN+ was an independent adverse predictor of OS (hazard ratio: 1.70, P = 0.007). Conclusions: This study suggests that the addition of PAD during pancreaticoduodenectomy does not improve the prognosis of patients with resectable pancreatic cancer and may lead to an increased risk of infection. However, the accurate preoperative assessment and appropriate treatment strategy for patients with PALN+ need further investigation due to the poor prognosis. [ABSTRACT FROM AUTHOR]

Neighbor searching is an essential and computationally heavy step in particle‐based numerical methods such as discrete element method (DEM), molecular dynamics, peridynamics, and smooth particle hydrodynamics. This article presents a novel approach to accelerate particle‐based simulations by leveraging ray tracing (RT) cores in addition to CUDA cores on RTX GPUs. The neighbor search problem is first numerically converted into a general ray tracing problem so that it can be possible to utilize the hardware acceleration of RT cores. A new, general‐purpose RT‐based neighbor search algorithm is then proposed and benchmarked with a prevailing cell‐based one. As a showcase, both algorithms are implemented into a GPU‐based DEM code for simulating large‐scale granular problems including packing, column collapse and debris flow. The overall simulation performance is examined with varying problem sizes and GPU specs. It demonstrates that the RT‐based simulations are 10%–60% faster than the cell‐based ones, depending on the simulated problems and GPU specs. This study offers a new recipe for next‐generation high‐performance computing of large‐scale engineering problems using particle‐based numerical methods. [ABSTRACT FROM AUTHOR]

Face‐based age estimation strongly depends on deep residual networks (ResNets), used as the backbone in the relevant research. However, ResNet‐based methods ignore the importance of some large‐scale facial information and other facial age attributes. Inspired by the attention mechanism, a multi‐task learning framework for face‐based age estimation called multi‐task multi‐scale attention is proposed. First, the authors embed the alternative strategy structure of dilated convolution into ResNet34 to construct a multi‐scale attention module (MSA) to improve the network's receptive field, which extracts local age‐sensitive information while obtaining multi‐scale features. The MSA can have a larger receptive field to extract both large‐scale and local detailed feature information. Second, multi‐task learning network structures are built to predict gender and race, which can share rigid network parameters to improve age estimation and improve the accuracy of age estimation by other age‐related parameters. Finally, the Kullback‐Leibler divergence loss is adopted between a Dirac delta label and a Gaussian prediction to guide the training. The numerical tests on the MORPH Album II and Adience datasets prove the superiority of the proposed method over other state‐of‐the‐art ones. [ABSTRACT FROM AUTHOR]

Glioma is a common tumor in the brain. CircRNA hsa_circ_0030018, also termed as hsa_circPOSTN_001 (circ_POSTN), is reported to exert a promoting influence on the development of glioma. Our study intends to deeply explore its regulation mechanism of circ_POSTN. Expression of circ_POSTN, microRNA-433-3p (miR-433-3p) and Secreted protein acidic and rich in cysteine (SPARC) was detected by qRT-PCR or western blot assay. The function of circ_POSTN was analyzed by loss-of-function experiments. The targeting relationship between miR-433-3p and circ_POSTN or SPARC was predicted by bioinformatics analysis and validated by dual-luciferase reporter assay. Xenograft modeling was employed to validate the function of circ_POSTN in glioma in vivo. circ_POSTN and SPARC were upregulated while miR-433-3p was downregulated in glioma tissues and cells. Both circ_POSTN and SPARC knockdown inhibited clonogenicity, migration, and promoted apoptosis of glioma cells. Circ_POSTN sponged miR-433-3p to regulate SPARC expression. Gain of SPARC largely attenuated circ_POSTN knockdown or miR-433-3p overexpression-mediated effects on glioma cell clonogenicity, migration, and apoptosis. Furthermore, silencing of circ_POSTN decreased xenograft tumor growth in vivo. Inhibition of circ_POSTN repressed glioma development, at least in part, via regulating the miR-433-3p/SPARC axis, providing evidence for circ_POSTN as a potential therapeutic target for glioma. [ABSTRACT FROM AUTHOR]

Background: Petal blotch is a unique ornamental trait in angiosperm families, and blotch in rose petal is rare and has great esthetic value. However, the cause of the formation of petal blotch in rose is still unclear. The influence of key enzyme genes and regulatory genes in the pigment synthesis pathways needs to be explored and clarified. Results: In this study, the rose cultivar 'Sunset Babylon Eyes' with rose-red to dark red blotch at the base of petal was selected as the experimental material. The HPLC-DAD and UPLC-TQ-MS analyses indicated that only cyanidin 3,5-O-diglucoside (Cy3G5G) contributed to the blotch pigmentation of 'Sunset Babylon Eyes', and the amounts of Cy3G5G varied at different developmental stages. Only flavonols but no flavone were found in blotch and non-blotch parts. As a consequence, kaempferol and its derivatives as well as quercetin and its derivatives may act as background colors during flower developmental stages. Despite of the differences in composition, the total content of carotenoids in blotch and non-blotch parts were similar, and carotenoids may just make the petals show a brighter color. Transcriptomic data, quantitative real-time PCR and promoter sequence analyses indicated that RC7G0058400 (F3'H), RC6G0470600 (DFR) and RC7G0212200 (ANS) may be the key enzyme genes for the early formation and color deepening of blotch at later stages. As for two transcription factor, RC7G0019000 (MYB) and RC1G0363600 (WRKY) may bind to the promoters of critical enzyme genes, or RC1G0363600 (WRKY) may bind to the promoter of RC7G0019000 (MYB) to activate the anthocyanin accumulation in blotch parts of 'Sunset Babylon Eyes'. Conclusions: Our findings provide a theoretical basis for the understanding of the chemical and molecular mechanism for the formation of petal blotch in rose. [ABSTRACT FROM AUTHOR]

Aero-optic imaging is a kind of optical effect, which describes the imaging deviation on the imaging plane. In this paper, the effect of the change of Mach number of blunt aircraft on the aero-optic imaging deviation is studied. The imaging deviations of Mach number 0.5–3 are analyzed systematically. The results show that with the increase of Mach number, imaging deviation increases gradually, and the increase rate is gradually slow. Imaging deviation slope decreases gradually with the increase of Mach number, and gradually tends to be zero, suggesting that imaging deviation is not sensitive to the change of the larger Mach number. In other words, the Mach number of smaller changes can lead to larger imaging deviation. As the Mach number of the aircraft increases, the slope of the imaging offset tends to be closer and closer to 0. When the Mach number of the aircraft increases to a certain extent, the change of the imaging offset will not have much influence. Therefore, in order to reduce the impact of flight speed on imaging migration, the aircraft should fly at a higher Mach number. [ABSTRACT FROM AUTHOR]

In this article, a sensorless control method based on signal injection and a high-pass filter (HPF) circuit is presented to control the unsymmetrical bistable multimagnetic circuit permanent magnetic actuator. In this method, a high-frequency sinusoidal signal was indirectly injected into the idle phase via a HPF circuit, and the peak of the high-frequency capacitance current was measured, which was used to calculate the idle phase inductance. Thereafter, the mover position was calculated by the one-to-one relationship between the idle phase inductance and the mover position. Combined with the HPF circuit and the proposed average current peak algorithm, the influences of back-EMF and coil resistance were eliminated. The magnetic saturation effects can also be ignored in the proposed strategy. The estimated noise, caused by measurement noise and signal distortion, was filtered using a simple mathematical filter. The flexibility and accuracy of the presented strategy were verified by simulation and experimental investigation. [ABSTRACT FROM AUTHOR]

There are many reports in the literatures on the use of phase change materials (PCMs) with photothermal conversion to store and harness solar energy. However, few works have reported intelligent PCMs with thermochromic capabilities that can controllably adjust their photothermal conversion efficiency to change the heating rate through temperature response. In this work, thermochromic phase change materials (TC‐PCMs) are successfully prepared by integrating the reversible thermochromic microcapsules into dynamically cross‐linked PCMs. The designed TC‐PCMs have a high photothermal conversion efficiency by using different styles of reversible thermochromic microcapsules, which can intelligently adjust the surface color of TC‐PCMs according to the substrate temperature under illumination conditions. Based on the fast temperature‐responsive thermochromic function of TC‐PCMs, the intriguing function of the reversible information storage and encryption can be realized by designing the shape and space of TC‐PCMs under the only thermal‐triggered condition. Importantly, the process of information storage and encryption can be controllable and reversible when repeatedly increasing and decreasing the external temperature. Additionally, TC‐PCMs capable of reprocessing ability based on dynamic oxime bond, are beneficial to the preparation of complex shape devices and recycling, expanding the application field of TC‐PCMs. [ABSTRACT FROM AUTHOR]

A double‐stator swing rotating permanent magnet spherical motor (SR‐PMSM) is designed, which can realize rotation, swing and spiral motion, and is used in the multi‐degree‐of‐freedom motion fields of industrial robot joints, torque gyroscopes, panoramic photography tables and so on. The inner surface of the rotor of the motor is attached with cylindrical PM poles, and the outer surface is attached with trapezoidal PM poles. Cylindrical and trapezoidal PM poles are simple to manufacture, but the magnetic field model of a spherical motor with two kinds of PM poles is complex. Therefore, a magnetic field modelling method combining the geometric equivalence principle and analytical method is proposed. Using the method of shape approximation, according to the principle of equivalence, the key parameters of cylindrical PM poles and trapezoidal PM poles are replaced by the parameters of approximate dihedral PM poles in a spherical coordinate. Select the most suitable dihedral PM poles, establish the analytical model of the magnetic field in the spherical coordinate system and verify the analytical results by FEM method. A SR‐PMSM motor with 6/4 pole (swing) and 12/10 pole (rotation) structure was assembled, and the experimental device was set up. The experimental results show that the experimental curve, analytical curve and FEM curve are in good agreement, which proves the accuracy of the equivalent model and is suitable for the magnetic field model of cylindrical and trapezoidal PM poles of the spherical motor. The research results of magnetic field lay a foundation for further analysis of the stator–rotor composite magnetic field considering cogging effect and edge effect, and analysis of load characteristics of the motor. [ABSTRACT FROM AUTHOR]

A new type of double‐stator permanent magnet spherical motor (DSSRPMSM) is proposed. Compared with most existing spherical motors, this motor uses a large number of stator iron cores, which can generate larger magnetic flux density and significantly improve torque capacity. The proposed DSSRPMSM can continuously rotate, swing and spiral, and can be used in the multi‐degree‐of‐freedom motion fields of industrial robot joints, moment gyroscopes, panoramic photography tables and so on. Because the motor has the dual characteristics of rotary motor and arc linear motor, the comprehensive effects of stator slotting and stator iron core breaking should be considered. Cylindrical and trapezoidal PM poles are equivalent to dihedral PM poles, and stator coils are equivalent to PM pole models. Analytical models of PM pole magnetic field and stator magnetic field in a spherical coordinate system are established, and the air gap magnetic flux density under unequal magnetic potential boundary conditions is calculated by conformal transformation. The analytical calculation method proposed is consistent with the results of finite element method (FEM) simulation, and the experimental test further verifies the effectiveness and accuracy of this method. [ABSTRACT FROM AUTHOR]

This paper presents a signed distance field (SDF) approach for unified discrete element method (DEM) modeling of granular media using arbitrarily shaped particles. The SDF approach employs a generic SDF-based interface defined by an SDF function and a surface projection function to rigorously model particle shapes and their ensuing complications on contact operations in DEM modeling. The signed distance is defined positive inside particles and negative when outside, and the zeroth isosurface of the SDF is conveniently used to represent the particle surface. The surface of a particle is discretized into a set of nodes. Node-to-surface algorithms are formulated to check the signs of the pertaining distance for contact detection. An energy-conserving contact theory is further employed to derive the contact interaction forces according to the contact potential defined on each intruding node. Based on the unified shape-contact description by SDF, specialised grain shape models are further developed to recover classical shape models as special cases, including poly-super-ellipsoid, poly-super-quadrics, spherical harmonics, polyhedron, and level set. A weighted spherical centroidal Voronoi tessellation-based numerical scheme is further developed for rigorous particle surface discretization and reconstruction. Demonstrative examples are presented to validate and showcase the capabilities of the proposed SDF approach for DEM modeling of granular media. The computational aspects, including the memory consumption and computational efficiency of the proposed approach for various particle models, are discussed. [ABSTRACT FROM AUTHOR]

By combining the flapping and rotary motion, a flapping wing rotor (FWR) shows unique kinematics of motion. It can produce a significantly higher aerodynamic efficiency and lift coefficient than insect-like flapping wings. However, due to the lack of controllable FWR aerial vehicles, the effect of different flapping parameters of the FWR on aerodynamic characteristics and efficiency remains to be evaluated experimentally. In this work, we conduct experimental studies to investigate the FWR's lift performance based on our previous vehicle design, which has demonstrated sustained stable hover and maneuver. In particular, by using such flyable FWR as the test platform, the changes in attack angle of the wing, the torsion of wings, different neutral positions, different up and down flapping angles, and different flapping amplitudes, were studied respectively. CFD simulation was used as an auxiliary and supplementary means for validation. As a result, design essentials to lift maximization of the FWR are proposed. The result proves that changing the attack angle and the torsion of the wing will have a certain impact on the lift. In addition, the ideal lift force can be generated when the neutral position tend to zero degrees and the up and down flapping angles tend to be equal. With the growth of the flapping amplitude, the lift force increases continuously. These experimental results provide important design cues for maximizing lift and payload capability of FWR-MAVs. [ABSTRACT FROM AUTHOR]

Background: Although a substantial increase in the survival of patients with other cancers has been observed in recent decades, pancreatic ductal adenocarcinoma (PDAC) remains one of the deadliest diseases. No effective screening approach exists. Methods: Differential exosomal long noncoding RNAs (lncRNAs) isolated from the serum of patients with PDAC and healthy individuals were profiled to screen for potential markers in liquid biopsies. The functions of LINC00623 in PDAC cell proliferation, migration and invasion were confirmed through in vivo and in vitro assays. RNA pulldown, RNA immunoprecipitation (RIP) and coimmunoprecipitation (Co-IP) assays and rescue experiments were performed to explore the molecular mechanisms of the LINC00623/NAT10 signaling axis in PDAC progression. Results: A novel lncRNA, LINC00623, was identified, and its diagnostic value was confirmed, as it could discriminate patients with PDAC from patients with benign pancreatic neoplasms and healthy individuals. Moreover, LINC00623 was shown to promote the tumorigenicity and migratory capacity of PDAC cells in vitro and in vivo. Mechanistically, LINC00623 bound to N-acetyltransferase 10 (NAT10) and blocked its ubiquitination-dependent degradation by recruiting the deubiquitinase USP39. As a key regulator of N4-acetylcytidine (ac4C) modification of mRNA, NAT10 was demonstrated to maintain the stability of oncogenic mRNAs and promote their translation efficiency through ac4C modification. Conclusions: Our data revealed the role of LINC00623/NAT10 signaling axis in PDAC progression, showing that it is a potential biomarker and therapeutic target for PDAC. [ABSTRACT FROM AUTHOR]

This article presents a new type of double stator swing rotating permanent magnet spherical motor (DSSRPMSM), which can realize swing, rotation, and helical motion and is used in industrial robots, gyroscopes, satellite communications, and other fields. The proposed spherical motor consists of two stators and a hollow rotor with permanent magnet (PM) poles on its inner and outer surfaces. Compared with most spherical motor with hollow coil and traditional PM synchronous motor, the structure of the motor is different and novel, and it is difficult to find a more perfect design theory and method. Thus, this article introduces the new idea of motor design in detail. First, the structure and working principle of the motor are introduced, and the original design of the motor is carried out. The 2-D rough estimation and 3-D FEM accurate simulation calculation are carried out, and the electromagnetic characteristics of the motor are obtained, including magnetic flux density distribution, torque, and loss. The simulation results meet the design specifications of the motor. A prototype was built and tested. The experimental results are in good agreement with the 3-D FEM analysis. The design method provides a theoretical basis for the design of this kind of spherical motor. The research results lay a foundation for the subsequent optimization of the motor. [ABSTRACT FROM AUTHOR]

The effects of heavy ion irradiation on the electrical response of HfO2-based ferroelectric capacitors have been studied. All the hysteresis loops measured from the irradiated samples shifted toward the positive voltage. The remanent polarization and relative permittivity of the capacitors decrease with increasing ion fluence. The leakage current exhibit negligible change after irradiation. The main reason causing the phenomena is swift heavy ions (SHIs) induced the pinning of domain walls, attributed to the phase transition. This work provides the possible physical mechanisms of SHIs irradiation on HfO2-based ferroelectrics, which is of significance for the space application of HfO2-based ferroelectric random access memory. [ABSTRACT FROM AUTHOR]

This study presents a scalable three‐dimensional (3D) multiscale framework for continuum‐discrete modeling of granular materials. The proposed framework features rigorous coupling of a continuum‐based material point method (MPM) and a discrete approach discrete element method (DEM) to enable cross‐scale modeling of boundary value problems pertaining to granular media. It employs MPM to solve the governing equations of a macroscopic continuum domain for a boundary value problem that may undergo large deformation. The required loading‐path‐dependent constitutive responses at each material point of the MPM are provided by a DEM solution based on grain‐scale contact‐based discrete simulations that receive macroscopic information at the specific material point as boundary conditions. This hierarchical coupling enables direct dialogs between the macro and micro scales of granular media while fully harnessing the predictive advantages of both MPM and DEM at the two scales. An effective, scalable parallel scheme is further developed, based on the flat message passing interface (MPI) model, to address the computational cost of the proposed framework for 3D large‐scale simulations. We demonstrate that the proposed parallel scheme may offer up to 32X and 40X speedup in strong and weak scaling tests, respectively, significantly empowering the numerical performance and predictive capability of the proposed framework. The 3D parallelized multiscale framework is validated by an element test and a column collapse problem, before being applied to simulate the intrusion of a solid object. The multiscale simulation successfully captures the characteristic response of intrusion as postulated by the modified Archimedes' law theory. The progressive development of the stagnant zone during the intrusion is further examined from a cross‐scale perspective. [ABSTRACT FROM AUTHOR]

In this paper, tetragonal barium titanate (BaTiO3) nanopowders were synthesized by a new wet chemical route named sol-hydrothermal method. The effects of different temperatures, time and raw materials on the properties of BaTiO3 were studied. The results showed that BaTiO3 was not formed in the precursors. All powders were pure perovskite phase except for the powder prepared using BaCl2 as raw material at 100 °C. The main morphology of the powders was near-spherical. With the increase of hydrothermal temperature and time, the agglomeration decreased, the crystallinity and the tetragonal content increased for the powders. The optimal conditions of tetragonal BaTiO3 nanopowders synthesized by different raw materials were 120 °C (BaCl2), 140 °C (BaAc2) and 160 °C for 24 h [Ba(NO3)2], respectively. The size of the powders prepared by optimal conditions ranges of 125 nm ~ 250 nm in diameter. Moreover, a possible formation mechanism was proposed for BaTiO3 nanopowders synthesized by the sol-hydrothermal method. The as-prepared tetragonal BaTiO3 powders could be used as medium material for multilayer ceramic capacitors. [ABSTRACT FROM AUTHOR]

Great efforts have been devoted to solving the issue that covalent thermosetting polymers and their composites, unlike thermoplastic polymers, are unable to undergo reprocessing via secondary melting or recycling through injection or extrusion after curing, which prevents them from forming three-dimensional network structures. However, tremendous attention has been focused on introducing specific dynamic covalent bonds or noncovalent bonds into the molecular structures of thermosetting polymers, which requires choosing or synthesizing particular monomers, greatly limiting the industrial application potential. Herein, we have devised and prepared a series of conventional thermosetting polyurea elastomers (TPUEs) by utilizing the commercial raw materials of poly(propylene oxide)diamine and different diisocyanate monomers. These TPUEs have remarkable solvent resistance, great thermal stability, and outstanding transparency in the visible light range. In particular, the toughness, the breaking strength, and the elongation at break of TPUEs can reach maximum values of 300 MJ m−3, 31.4 MPa, and 1752%, respectively, making them superior to most dynamic materials and commercial elastomers that exhibit exceptional mechanical properties. Surprisingly, the TPUEs devised here have a superior dynamic nature owing to the classic urea bond, as confirmed via analysis of small molecules and dynamic properties, such as stress-relaxation and creep–recovery. These TPUEs can maintain remarkable mechanical properties, chemical stability, and solvent resistance after being recycled multiple times. Additionally, we propose a universal mechanism by which these TPUEs can simultaneously have mechanically robust properties in the range from the glass transition temperature of the soft segment (Tgs) to their topology freezing-transition temperature (Tv) (about −40 °C to 150 °C) and excellent recyclability at temperatures ranging from Tv to the thermal decomposition temperature (Td) (about 150 °C to 220 °C). Integration of mechanical robustness and a dynamic nature into one network can provide a facile way to solve the recyclability issues relating to conventional TPUEs. [ABSTRACT FROM AUTHOR]

In this article, a novel single-switch, high step-up dc–dc converter based on three-winding coupled inductor and voltage multiplier circuit (VMC) is proposed. And on this basis, pump capacitor unit (PCU) is integrated to achieve a very high voltage gain. The converter makes full use of the advantages of three-winding coupled inductor, skillfully combines it with the VMC, and integrates the PCU that can be used in superposition to further improve the voltage gain. The voltage stress of the switch is reduced by using a passive clamping circuit to recycle the leakage energy of the coupled inductor. The operating principle and steady-state analysis of the presented converter in continuous conduction mode are introduced in detail. Moreover, the comparative analysis shows that under the same conditions, the proposed converter has higher voltage gain and lower voltage stress than others. Several advantages include high voltage gain, low voltage stress, low turns ratio of coupled inductor, and high conversion efficiency, make the proposed converter very suitable for new energy generation applications, such as photovoltaic systems. Finally, the feasibility of the proposed converter and the correctness of theoretical analysis are verified by a 500-W prototype at 50 kHz switching frequency. [ABSTRACT FROM AUTHOR]

Granular-continuum interfaces commonly exist in geotechnical engineering practices, such as foundations, reinforcements, and soil nailing. The mechanical behaviors and fabric of the interface are not only influenced by the soil properties but the interfaces, and normal stresses. Therefore, a thorough understanding of the granular-continuum interface is essential to engineering practices. This article investigates the interface shear behavior focusing on the normal stresses and soil densities by using the three-dimensional discrete element modeling (DEM). The influence zones resulting from counterface mobilization vary with the normal stresses and soil densities. The interface shearing problem physics obtained from DEM have been demonstrated to be consistent with the experiments. Based on the DEM model, the evolution of the micromechanical behaviors and fabric for the immediate influence zone of the interface at both failure and the critical state are investigated, such as fabric anisotropy, sliding fraction, and mechanical coordination number. The stress tensor and fabric tensor, determined from the granular assembly in the influence zone, are used to capture the interface shear strength. Results show that, due to the evolution of particle interlock and dilation, both the macro and micro mechanical parameters decrease mostly with the increasing confining stress at both failure and the critical state. [ABSTRACT FROM AUTHOR]

Soil aggregate breakdown is the key step of splash erosion. Recent studies have shown that it is the soil internal forces that induce aggregate breakdown and subsequent splash erosion. However, little is known about the size characteristics of soil aggregate breakdown and corresponding effects on splash erosion. In this study, Cinnamon soil and Heilu soil were adopted to investigate the effects of soil internal forces on the characteristics of aggregate fragments and splash erosion through wet sieving and rainfall simulation. The results showed the following. (1) With a decrease in electrolyte concentration in soil solution, soil net repulsive force increased; meanwhile, aggregate stability decreased and splash erosion rate increased. Additionally, when the electrolyte concentration was less than 10−2 mol L−1, soil net repulsive force hardly changed, and aggregate stability and splash erosion rate accordingly varied very little. (2) With the increase in the soil net repulsive force, the content of fragments <0.053 mm released from aggregates increased, whereas the content of fragments >0.25 mm decreased, thus suggesting that the aggregates tended to break into fine fractions as soil net repulsive forces increased. (3) Regression analyses showed that soil splash erosion rate decreased linearly with increases in the aggregate stability; moreover, correlation analyses showed that splash erosion rate was significantly and positively correlated with the fragments with a diameter of <0.053 mm, and negatively correlated with the fragments with a diameter of >0.25 mm. This study suggests that soil internal forces induce the aggregate crush and determine the size distribution of fragments available for mobilization by the raindrop impact force. Also, the raindrop impact force is the driving mechanism leading to the movement of fragments. This study provides new insights into the mechanism responsible for splash erosion and could be valuable for controlling soil erosion. Highlights: Soil aggregates breakdown dynamics and splash erosion were quantitatively investigated.Soil internal forces determined the size distribution of fragments after aggregates breakdown.The movement of soil fragments largely depended on raindrop impact force.Splash erosion was driven by the soil internal forces and raindrop impact force. [ABSTRACT FROM AUTHOR]

Purpose: Soil aggregate stability associates closely with many environmental and agricultural problems. Some studies using the model aggregates find that soil internal forces exert an important impact on soil aggregate stability. However, the effect of soil internal forces on the stability of natural soil aggregates during vegetation restoration has been little studied. Methods: Five different succession stages (including farmland, grassland, shrubland, early forest, and climax forest) were chosen in the Ziwuling forest region (in the central part of the Loess Plateau, China), and the size distribution and stability of natural soil aggregates under different succession stages were investigated through dry sieving and wet sieving with ethanol and deionized water prewetting. Results: The size distribution of aggregates determined by dry sieving showed decreased first and then increased with decreasing particle size, dominant sizes were 5–1- and < 0.15-mm fractions. The ethanol prewetting treatment showed a distribution similar to that determined by dry sieving. The size distribution of aggregates in deionized water prewetting treatment was mainly < 0.15-mm fractions. Moreover, the mean weight diameter values of farmland, grassland, shrubland, early forest, and climax forest soils determined in ethanol treatment (MWDe) were 4.62, 1.45, 1.31, 1.32, and 1.17 times than those in deionized water treatment (MWDw). In addition, in the fast wetting process, the preservation rate of soil aggregates was higher in 0.5–0.053-mm fractions than in > 0.5-mm fractions. The relative internal force index (RII) of grassland, shrubland, early forest, and climax forest soils decreased by 47%, 54%, 55%, and 64% compared with that of farmland soil, respectively. Conclusions: These findings demonstrate that soil internal forces could significantly break down the aggregates and lead to decreasing water stability of aggregates. The vegetation restoration process decreased the repulsive soil internal forces, thereby decreasing the degree of disintegration of aggregates and consequently increased the water stability of aggregates. [ABSTRACT FROM AUTHOR]

Rose is one of the most fundamental ornamental crops, but its yield and quality are highly limited by drought. The key transcription factors (TFs) and co-expression networks during rose's response to drought stress and recovery after drought stress are still limited. In this study, the transcriptomes of leaves of 2-year-old cutting seedlings of Rosa chinensis 'Old Blush' from three continuous droughted stages (30, 60, 90 days after full watering) and rewatering were analyzed using RNA sequencing. Weighted gene co-expression network analysis (WGCNA) was used to construct a co-expression network, which was associated with the physiological traits of drought response to discovering the hub TFs involved in drought response. More than 45 million high-quality clean reads were generated from the sample and used for comparison with the rose reference genome. A total of 46433 differentially expressed genes (DEGs) were identified. Gene Ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that drought stress caused significant changes in signal transduction, plant hormones including ABA, auxin, brassinosteroid (BR), cytokinin, ethylene (ET), jasmonic acid (JA) and salicylic acid (SA), primary and secondary metabolism, and a certain degree of recovery after rewatering. Gene co-expression analysis identified 18 modules, in which four modules showed a high degree of correlation with physiological traits. In addition, 42 TFs including members of NACs, WRKYs, MYBs, AP2/ERFs, ARFs , and bHLHs with high connectivity in navajowhite1 and blue modules were screened. This study provides the transcriptome sequencing report of R. chinensis 'Old Blush' during drought stress and rewatering process. The study also identifies the response of candidate TFs to drought stress, providing guidelines for improving the drought tolerance of the rose through molecular breeding in the future. [ABSTRACT FROM AUTHOR]

The at-rest coefficient of lateral pressure, K 0 , is a critical macroscopic parameter for evaluating stress transmission in granular media for engineering practice. This paper revisits the microscopic origin of K 0 and its corresponding underlying physics based on micromechanics-based theories and numerical simulations, with a focus placed on the effect of particle shape. Two typical kinds of distortion (elongation and blockiness) in particle shape are considered, modeled by ellipsoids and superballs in the discrete element method. One-dimensional compression tests are performed on numerical specimens with dense and loose initial states for different particle shapes. An analytical relationship between K 0 and anisotropy of fabric measures (i.e., contact normal, contact force, and shape-related anisotropy) is established within the stress-force-fabric framework. It is found that the analytical K 0 is consistent with the measured one directly from the simulation regardless of particle shape, verifying a well-established relationship between K 0 and fabric. It is further found that contact force partition of K 0 plays the most prominent role in K 0 compared to contact normal and shape-related partitions. Results also reveal the different influence of shape distortion on K 0 and the corresponding mechanical properties related to K 0 , such as void ratio, mobilized friction angle, and coordination number. More specifically, K 0 has a 'W'-shape relationship with elongation for dense ellipsoids and an 'M'-shape relationship with blockiness for superballs. [ABSTRACT FROM AUTHOR]

In this paper, a new reconfigurable power divider (PD) is proposed to improve the efficiency of the three-way Doherty power amplifier (DPA). The conventional λ/4 transmission line is replaced by the proposed reconfigurable PD in the input of peaking amplifier, where the 90° phase shift and impedance matching can be achieved. Furthermore, the output power distribution ratio (PDR) can be continuously adjusted in a large range by adjusting the reverse voltage of the varactor diodes. Therefore, the reconfigurable PD with the best PDR can assign input power to the peaking amplifier. Experiment results show that the maximum measured power added efficiency (PAE) of the proposed three-way DPA is 49%, which is improved by 5% compared with conventional three-way DPA. [ABSTRACT FROM AUTHOR]

A complementary tunable method is proposed based on the Hybrid coupler. The odd-even mode analysis shows that the method can achieve continuously tunable power division ratio by changing two 50 / 2 Ω transmission lines in the circuit, and it can achieve larger tunable range by improving the complementary tunable method based on the cascaded Hybrid coupler. Using the improved method, a novel π-type reconfigurable coupler, which works at 2.45 GHz, is designed by replacing 50 / 2 Ω transmission lines with π-type circuit. The power division ratio of the fabricated reconfigurable coupler is changed in the range of −20.5–21.3 dB, with the bias voltage being 0∼6 V; meanwhile, the isolation and return loss are above 20 dB. [ABSTRACT FROM AUTHOR]