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Glucose metabolism in fish remains a controversial area of research as many fish species are traditionally considered glucose-intolerant. Although energy homeostasis remodeling has been observed in fish with inhibited fatty acid β-oxidation (FAO), the effects and mechanism of the remodeling caused by blocked glucose uptake remain poorly understood. In this study, we blocked glucose uptake by knocking out glut2 in zebrafish. Intriguingly, the complete lethality, found in Glut2-null mice, was not observed in glut2−/− zebrafish. Approxiamately 30% of glut2−/− fish survived to adulthood and could reproduce. The maternal zygotic mutant glut2 (MZglut2) fish exhibited growth retardation, decreased blood and tissue glucose levels, and low locomotion activity. The decreased pancreatic β-cell numbers and insulin expression, as well as liver insulin receptor a (insra), fatty acid synthesis (chrebp, srebf1, fasn, fads2, and scd), triglyceride synthesis (dgat1a), and muscle mechanistic target of rapamycin kinase (mtor) of MZglut2 zebrafish, suggest impaired insulin-dependent anabolic metabolism. Upregulated expression of lipolysis (atgl and lpl) and FAO genes (cpt1aa and cpt1ab) in the liver and proteolysis genes (bckdk, glud1b, and murf1a) in muscle were observed in the MZglut2 zebrafish, as well as elevated levels of P-AMPK proteins in both the liver and muscle, indicating enhanced catabolic metabolism associated with AMPK signaling. In addition, decreased amino acids and elevated carnitines of the MZglut2 zebrafish supported the decreased protein and lipid content of the whole fish. In summary, we found that blocked glucose uptake impaired insulin signaling-mediated anabolism via β-cell loss, while AMPK signaling-mediated catabolism was enhanced. These findings reveal the mechanism of energy homeostasis remodeling caused by blocked glucose uptake, which may be a potential strategy for adapting to low glucose levels.

Benzene is used as an industrial solvent, which may result in chronic benzene poisoning (CBP). Several studies suggested that CBP was associated with mitochondrial epigenetic regulation. This study aimed to explore the potential relation between CBP and mitochondrial DNA (mtDNA) methylation. This prospective observational study enrolled CBP patients admitted to Shenzhen Prevention and Treatment Center for Occupational Diseases hospital and healthy individuals between 2018 and 2021. The white blood cell (WBC), red blood cell (RBC), hemoglobin (HB), and platelet (PLT) counts and mtDNA methylation levels were measured using blood flow cytometry and targeted bisulfite sequencing, respectively. A total of 90 participants were recruited, including 30 cases of CBP (20 females, mean age 43.0 ± 8.0 years) and 60 healthy individuals (42 females, mean age 43.5 ± 11.5 years). This study detected 168 mitochondrial methylation sites >0 in all study subjects. The mtDNA methylation levels in the CBP cases were lower than the healthy individuals [median ± interquartile-range (IQR), 25th percentile, 75th percentile: (1.140 ± 0.570, 0.965, 1.535)% vs. median ± IQR, 25th percentile, 75th percentile: (1.705 ± 0.205,1.240,2.445)%, P < 0.05]. Additionally, the spearman correlation analysis showed that the mtDNA methylation levels were positively correlated with the counts of circulating leukocytes [WBC (r = 0.048, P = 0.036)] and platelets [PLT (r = 0.129, P < 0.01)]. We provided solid evidence of association between CBP and aberrant mtDNA methylation.

In this paper, a new $C^1$-conforming Petrov-Galerkin method for convection-diffusion equations is designed and analyzed. The trail space of the proposed method is a $C^1$-conforming ${\mathbb Q}_k$ (i.e., tensor product of polynomials of degree at most $k$) finite element space while the test space is taken as the $L^2$ (discontinuous) piecewise ${\mathbb Q}_{k-2}$ polynomial space. Existence and uniqueness of the numerical solution is proved and optimal error estimates in all $L^2, H^1, H^2$-norms are established. In addition, superconvergence properties of the new method are investigated and superconvergence points/lines are identified at mesh nodes (with order $2k-2$ for both function value and derivatives), at roots of a special Jacobi polynomial, and at the Lobatto lines and Gauss lines with rigorous theoretical analysis. In order to reduce the global regularity requirement, interior a priori error estimates in the $L^2, H^1, H^2$-norms are derived. Numerical experiments are presented to confirm theoretical findings.

Accurate detection and segmentation of obstacles is the key to the smooth operation of the planetary rovers and the basic guarantee of scientific exploration mission. The traditional method of rock...

Different cooling rates, such as room temperature water cooling (WQ), furnace cooling (FC), and water cooling + furnace cooling (FC +WQ), were introduced to study the effect on the solution-treated Mg-9Gd-4Y-2Zn-0.5Zr (w/%) alloy microstructure and mechanical properties. The grain size decreases as the cooling rate increases. With the lengthening of the cooling process time, the LPSO phase had enough time to nucleate and diffuse, the LPSO (long-period stacking order) phase filled the whole matrix crystal grains at the same time. In the process of furnace cooling and water cooling, the brightness of the LPSO phase was different, so it could be seen that the cooling rate would affect the contrast and morphology of the LPSO phase. The tensile yield strengths of the samples cooled with the furnace were better than those of the water-cooled samples, but their ultimate tensile strength and elongation to failure were poor. The fracture modes of the samples under different cooling rates were all subject to cleavage fracture, and the number and area of the cleavage planes and cleavage steps increased with the decrease of cooling speed, and the tearing area decreased, resulting in poor ultimate tensile strength and stretchability.

An hp-version interior penalty discontinuous Galerkin (IPDG) method under nonconforming meshes is proposed to solve the quad-curl eigenvalue problem. We prove well-posedness of the numerical scheme for the quad-curl equation and then derive an error estimate in a mesh-dependent norm, which is optimal with respect to h but has different p-version error bounds under conforming and nonconforming tetrahedron meshes. The hp-version discrete compactness of the DG space is established for the convergence proof. The performance of the method is demonstrated by numerical experiments using conforming/nonconforming meshes and h-version/p-version refinement. The optimal h-version convergence rate and the exponential p-version convergence rate are observed.

Using newly developed ${\bf H}(\mathrm{curl}^2)$ conforming elements, we solve the Maxwell's transmission eigenvalue problem. Both real and complex eigenvalues are considered. Based on the fixed-point weak formulation with reasonable assumptions, the optimal error estimates for numerical eigenvalues and eigenfunctions (in the ${\bf H}(\mathrm{curl}^2)$-norm and ${\bf H}(\mathrm{curl})$-semi-norm) are established.

In the past few years, there has been a dramatic growth in e-manga (electronic Japanese-style comics). Faced with the booming demand for manga research and the large amount of unlabeled manga data, we raised a new task, called unsupervised manga character re-identification. However, the artistic expression and stylistic limitations of manga pose many challenges to the re-identification problem. Inspired by the idea that some content-related features may help clustering, we propose a Face-body and Spatial-temporal Associated Clustering method (FSAC). In the face-body combination module, a face-body graph is constructed to solve problems such as exaggeration and deformation in artistic creation by using the integrity of the image. In the spatial-temporal relationship correction module, we analyze the appearance features of characters and design a temporal-spatial-related triplet loss to fine-tune the clustering. Extensive experiments on a manga book dataset with 109 volumes validate the superiority of our method in unsupervised manga character re-identification.

We introduce and analyze a robust nonconforming finite element method for a three dimensional singularly perturbed quad-curl model problem. For the solution of the model problem, we derive proper a priori bounds, based on which, we prove that the proposed finite element method is robust with respect to the singular perturbation parameter $\varepsilon$ and the numerical solution is uniformly convergent with order $h^{1/2}$. In addition, we investigate the effect of treating the second boundary condition weakly by Nitsche's method. We show that such a treatment leads to sharper error estimates than imposing the boundary condition strongly when the parameter $\varepsilon< h$. Finally, numerical experiments are provided to illustrate the good performance of the method and confirm our theoretical predictions.

Thrombotic thrombocytopenic purpura (TTP) is an acute life-threatening disease usually treated with therapeutic plasma exchange (TPE), but some patients are refractory to TPE. The study aimed to compare lymphoplasmapheresis (LPE), an innovative treatment for TTP based on plasma exchange, with TPE in TTP treatment. This retrospective study included patients with TTP treated at Xiang-Ya Hospital in China during 2009-2018. All patients with microangiopathic hemolysis and thrombocytopenia who received either LPE or TPE were included. The treatment outcomes were the number of sessions, volume of plasma, time in hospital, hospital costs, and rates of remission and relapse. All patients attended the hospital for follow-up. Forty-five patients were included in the study; 18 received TPE and 27 LPE. There were no significant differences in sex, etiology of TTP, initial platelet count, schistocyte, LDH, and bilirubin between the two groups. At the time of discharge, patients treated with TPE required more treatment sessions (4.5 vs. 2, P=0.04) and higher plasma volume (7300 vs. 3100 ml, P=0.01) than patients treated with LPE. The proportions of remission (P=0.197) and relapse (P=0.257) were not significantly different between the two groups. The time to remission from admission (P=0.75) and the time to remission from first therapy (P=0.53) were also not significantly different between the two groups. Compared with TPE, LPE reduced the number of treatment sessions and plasma volume needed to treat TTP. Therefore, we propose that LPE might be a suitable treatment for TTP.

We propose two families of nonconforming elements on cubical meshes: one for the $-\text{curl}Δ\text{curl}$ problem and the other for the Brinkman problem. The element for the $-\text{curl}Δ\text{curl}$ problem is the first nonconforming element on cubical meshes. The element for the Brinkman problem can yield a uniformly stable finite element method with respect to the parameter $ν$. The lowest-order elements for the $-\text{curl}Δ\text{curl}$ and the Brinkman problems have 48 and 30 degrees of freedom, respectively. The two families of elements are subspaces of $H(\text{curl};Ω)$ and $H(\text{div};Ω)$, and they, as nonconforming approximation to $H(\text{gradcurl};Ω)$ and $[H^1(Ω)]^3$, can form a discrete Stokes complex together with the Lagrange element and the $L^2$ element.

With the rapid growth of the electric vehicles (EVs) market all over the world, wireless power transfer (WPT), as an emerging way of charging batteries, has drawn the attention of researchers, manufactures, and customers recently. Various magnetic coupler configurations, which are essential in WPT systems, have been proposed and analyzed. However, the misalignment tolerances of the existing magnetic couplers are pretty small, which results in a remarkable decrease in the transmission power and efficiency when there is misalignment between two coupling coils. In order to solve this problem, novel quadrature coils and a converting circuit are proposed, which could adjust the coupler structure according to the relative position of the coils on both sides so that the transmission power and efficiency are optimal. The structure of quadrature coils is first optimized with a three-dimensional finite element analysis (3-D FEA) tool ANSYS MAXWELL. On the basis of the optimized parameters, a 3.5 kW WPT experiment platform is constructed. When the horizontal misalignment reaches 150 mm, the input and output power is 2.256 kW and 2.126 kW respectively, thus an efficiency of 94.22% is achieved. The experimental results verify the correctness of the theoretical analysis.

The effect of repeated swelling of rock on tunnels and other structures becomes more apparent with the continuous development of the transportation infrastructure in China. Tests on the free swelling ratio, lateral constraint swelling ratio, and lateral constraint swelling stress were conducted for different dry–wet cycles and drying temperatures, with the samples taken from Zhuzhou in Hunan Province (China). The test results show that the free swelling ratio, lateral constraint swelling ratio, and swelling stress of rock are all dependent on time. The swelling phases can be characterized as rapid, moderate, and slow phases. The dry–wet cycle and drying temperature have a significant effect on the swelling behavior of red sandstone. At larger axial and radial free swelling ratios, the lateral constraint swelling ratio and swelling stress occur at a higher drying temperature. Furthermore, the lateral constraint swelling ratio and swelling stress first increase with an increasing number of cycles and then gradually decrease and reach maximum values in the second and third cycles, respectively. Based on the sigmoid and power functions, the time-history models for the lateral constraint swelling ratio and lateral constraint swelling stress are established, considering the effects of the cycle number and drying temperature. In addition, the results of this study are significant and may serve as an engineering guide for the swelling of rock during construction.

The multi-pass hot compressive tests of Ti-6Al-4V alloy prepared by hot isostatic pressing were carried out. The results show that the flow stress with the strain rates of 1s−1 and 5s−1 both in first-pass at 1050°C and second-pass at 1000°C deformation, also with the strain rate of 5s−1 in third-pass at 950°C deformation, exhibit obvious dynamic softening behavior. For first-pass deformation with the strain rate ranging from 0.001s-1 to 0.1s-1, a few equiaxed β grains can be observed and the larger strain rate resulted in the smaller dynamic recrystallization (DRX) grains. For second-pass deformation, a number of finer DRX β grains and a few DRX α grains can be observed under 0.01s−1 strain rate. The grain boundary is indistinguishable and a small number of DRX grains adhere to the grain boundary under 0.1s−1 and 1s-1 strain rates; there are plenty of lamellar α structure and a few basketweave structures. For third-pass deformation, there are equiaxed β grains and equiaxed primary α grains under 0.1s-1 strain rate. Moreover, a small number of globularization α grains can be observed. As the strain rate increasing to 1s-1, a great many of interlaced fine lamellar α phases precipitated inside the β grain.

Compression tests of a Mg-13Gd-4Y-2Zn-0.5Zr alloy were carried out on a Gleeble-1500D thermo-mechanical simulator within a temperature range of 420–500 °C and strain rate of 0.001–5 s–1 so that the corresponding flow behavior was investigated. The Zener-Hollomon parameter Z was used in a hyperbolic-sine-type equation to express the relationships between the peak stress, deformation temperature and strain rate. Work hardening, dynamic recovery and dynamic recrystallization were the main characteristics affecting the plastic-deformation behaviors. The activation energy Q was calculated to be 208.2 kJ/mol and processing maps at strains of 0.3, 0.5 and 0.7 were generated based on a dynamic material model. The optimum processing parameters were obtained with a power-dissipation analysis.

In this study a high-velocity air-fuel (HVAF) flame-sprayed WC-10Co4Cr coating was heat-treated at (240; 300; 400) °C for 2 h in an air atmosphere. The effect of the heat treatment on the hardness, fracture toughness, wear resistance, corrosion resistance, phase composition and microstructure behaviour of the coatings was investigated. It could be concluded from the X-ray diffraction (XRD) pattern that the phase of the coatings was mainly composed of tungsten carbide, an amorphous phase, a small amount of W2C and trace metal tungsten. However, the heat-treated coating had a small increase in W2C compared to the original coating, although the amount of amorphous phase did not decrease significantly. The results indicated that as the heat-treatment temperature increased, the hardness of the coating first increased and then decreased, while the fracture toughness increased. The polarization test confirmed that the heat-treated coating had higher corrosion resistance than the original coating. In addition, the results of the reciprocating friction and wear test indicated that small amounts of W2C strengthening phases were formed in the WC-10Co4Cr coating after heat treatment at 400 °C. This process did not eliminate many of the tougher Co and WC phases. Therefore, this coating had the best wear resistance among all the comparative coatings.

Anderson localization is a famous wave phenomenon that describes the absence of diffusion of waves in a disordered medium. Here we generalize the landscape theory of Anderson localization to general elliptic operators and complex boundary conditions using a probabilistic approach, and further investigate some mathematical aspects of Anderson localization that are rarely discussed before. First, we observe that under the Neumann boundary condition, the low energy quantum states are localized on the boundary of the domain with high probability. We provide a detailed explanation of this phenomenon using the concept of extended subregions and obtain an analytical expression of this probability in the one-dimensional case. Second, we find that the quantum states may be localized in multiple different subregions with high probability in the one-dimensional case and we derive an explicit expression of this probability for various boundary conditions. Finally, we examine a bifurcation phenomenon of the localization subregion as the strength of disorder varies. The critical threshold of bifurcation is analytically computed based on a toy model and the dependence of the critical threshold on model parameters is analyzed., 31 pages, 7 figures

Vibrations of structures subjected to concentrated point loads have many applications in mechanical engineering. Experiments are expensive and numerical methods are often used for simulations. In this paper, we consider the plate vibration with nonlinear dependence on the eigen-parameter. The problem is formulated as the eigenvalue problem of a holomorphic Fredholm operator function. The Bogner-Fox-Schmit element is used for the discretization and the spectral indicator method is employed to compute the eigenvalues. The convergence is proved using the abstract approximation theory of Karma. Numerical examples are presented for validations.

We here present a DMD based low-cost digital lithography system, and report the results of microstructure fabrication experiments on both glass slide substrates and single mode optical fiber end faces. The system possesses the ability to rapidly fabricate microstructures in sub-micron scale, and the characteristic of fabricating on unconventional substrates such as optical fiber end faces. Through the processing procedure of “visible light – chromatic aberration and optical path difference correction – ultraviolet light”, the function of visual focusing was supported, without sacrificing part of the photoresist film. With above-mentioned features, the system is promising to accelerate the processing and construction of experimental sub-micron scale microstructure prototypes, especially micro-element prototypes on fiber end faces.

We report a direct and facile method to study the limit resolution of optical fiber microlithography, which is based on DMD (digital micromirror device) the fiber end face of submicron uv lithography system, with 365 nm uv light, supplemented by 620–630 nm red light for focusing the reference light source, using the Reduced projection objective lens will focus the DMD modulation of the ultraviolet light on the spin of the photoresist fiber end face, realize the optical fiber end surface microstructure (single exposure precision 900 nanometers, single exposure area of more than hundred microns) preparation. By changing the magnification of the objective and Number of pixels in a single cycle of digital mask, the influence of the Objectives with different magnification and the pixel point on the precision and integrity of the microstructure was analyzed, and the lithography experiment was carried out to verify and get the optimal solution between the two factors.

Extend lifetime of near-earth orbit satellites by on-orbit refueling has significant economic benefits, while the orbit deployment strategy of the on-orbit servicing (OOS) system which implements the refueling task directly affects the efficiency of on-orbit refueling mission. Three orbit deployment modes were proposed, including ground deployment, low earth orbit (LEO) deployment and the same orbit deployment. For the client satellites to be refueled on near-earth orbit including LEO, medium earth orbit (MEO) and geosynchronous orbit (GEO), the three deployment modes were compared quantitatively based on two evaluation indicators: the refueling response time and the economic benefits. The comparing results showed that for MEO and GEO client satellites, it is appropriate to adopt the same orbit deployment mode, while for LEO client satellites, ground deployment mode is more suitable. As the maximum economic benefits can be earned to refuel GEO client satellites, the orbit deployment scheme of OOS system for refueling GEO client satellites was further studied. A new architecture of OOS system called “1+N” consist of 1 fuel storage station and N refueling vehicles was proposed. The fuel storage station carries a great deal of fuel, running on orbit steadily. The refueling vehicles maneuver on GEO and implement the refueling operations for GEO client satellites. If the vehicles run out of fuel, they arrive at the station to be refueled. The weight and orbital altitude of fuel storage station, the number, weight, orbital altitude and orbital phase of refueling vehicles are the key parameters of the orbit deployment scheme. The mathematical model for optimizing the scheme was constructed, which takes shorten the refueling response time and lower the cost of OOS system as multi-objective. The calculation process of the optimization was explained. By analyzing the optimization results, the optimal orbit deployment scheme of OOS system containing 1 fuel storage station and 4 to 6 refueling vehicles was proposed.

In this study, instant catapult steam explosion (ICSE) was employed for chitin treatment, and the effect of ICSE on the chitin structure was systematically investigated by using a series of analytical techniques including scanning electron microscopy, X-ray diffraction and Brunauer-Emmett-Teller analysis. Due to the powerful seepage force of the steam during ICSE, the crystallinity index of chitin decreased 10.2% in the (1 1 0) plane and 13.3% in the (0 2 0) plane. Significantly larger surface areas (up to 2.5 times greater, 12.69 m²/g at 1.6 MPa) with more and larger pores (up to a 3.5 times larger pore volume, 0.0333 cm³/g at 2.0 MPa) were achieved after ICSE, and numerous lacerated-like pore shapes were observed on the porous surface of chitin. Importantly, the molecular structure of chitin remained intact with no substantial damage to chitin’s molecular weight, thermostability and acetylation (∼70%), which ensures the possibility and diversity of further chitin derivatization.

We investigate numerical solutions of high order curl problems with various formulations and finite elements. We show that several classical conforming finite elements lead to spurious solutions, while mixed formulations with finite elements in complexes solve the problems correctly. To explain the numerical results, we clarify the cohomological structures in high order curl problems by relating the partial differential equations to the Hodge-Laplacian boundary problems of the gradcurl-complexes., Comment: 23 pages, 7 figures

In this work, we analyze the three-step backward differentiation formula (BDF3) method for solving the Allen-Cahn equation on variable grids. For BDF2 method, the discrete orthogonal convolution (DOC) kernels are positive, the stability and convergence analysis are well established in [Liao and Zhang, \newblock Math. Comp., \textbf{90} (2021) 1207--1226; Chen, Yu, and Zhang, \newblock SIAM J. Numer. Anal., Major Revised]. However, the numerical analysis for BDF3 method with variable steps seems to be highly nontrivial, since the DOC kernels are not always positive. By developing a novel spectral norm inequality, the unconditional stability and convergence are rigorously proved under the updated step ratio restriction $r_k:=\tau_k/\tau_{k-1}\leq 1.405$ (compared with $r_k\leq 1.199$ in [Calvo and Grigorieff, \newblock BIT. \textbf{42} (2002) 689--701]) for BDF3 method. Finally, numerical experiments are performed to illustrate the theoretical results. To the best of our knowledge, this is the first theoretical analysis of variable steps BDF3 method for the Allen-Cahn equation.

A detailed description of the proposed method and more experiment results quantitatively analyzed by FRC.

Hierarchical Text Classification (HTC), which aims to predict text labels organized in hierarchical space, is a significant task lacking in investigation in natural language processing. Existing methods usually encode the entire hierarchical structure and fail to construct a robust label-dependent model, making it hard to make accurate predictions on sparse lower-level labels and achieving low Macro-F1. In this paper, we propose a novel PAMM-HiA-T5 model for HTC: a hierarchy-aware T5 model with path-adaptive mask mechanism that not only builds the knowledge of upper-level labels into low-level ones but also introduces path dependency information in label prediction. Specifically, we generate a multi-level sequential label structure to exploit hierarchical dependency across different levels with Breadth-First Search (BFS) and T5 model. To further improve label dependency prediction within each path, we then propose an original path-adaptive mask mechanism (PAMM) to identify the label's path information, eliminating sources of noises from other paths. Comprehensive experiments on three benchmark datasets show that our novel PAMM-HiA-T5 model greatly outperforms all state-of-the-art HTC approaches especially in Macro-F1. The ablation studies show that the improvements mainly come from our innovative approach instead of T5.

In this paper, we propose an $H(\text{curl}^2)$-conforming quadrilateral spectral element method to solve quad-curl problems. Starting with generalized Jacobi polynomials, we first introduce quasi-orthogonal polynomial systems for vector fields over rectangles. $H(\text{curl}^2)$-conforming elements over arbitrary convex quadrilaterals are then constructed explicitly in a hierarchical pattern using the contravariant transform together with the bilinear mapping from the reference square onto each quadrilateral. It is astonishing that both the simplest rectangular and quadrilateral spectral elements possess only 8 degrees of freedom on each physical element. In the sequel, we propose our $H(\text{curl}^2)$-conforming quadrilateral spectral element approximation based on the mixed weak formulation to solve the quad-curl equation and its eigenvalue problem. Numerical results show the effectiveness and efficiency of our method.

Atrial fibrillation (AF) and First-degree atrioventricular block (I-AVB) are two common arrhythmia diseases, which can lead to different cardiovascular diseases. Therefore, it is of great significance to realize the automatic diagnosis of AF and I-AVB. In this paper, a support vector machine (SVM) automatic detection method based on P-wave and RR interval features was proposed to classify normal (N), AF, and I-AVB. The method consists of three steps: 1) detection of the P wave and R wave reference points in the signal; 2) feature extraction, including analysis of P wave features extracted from the atrial activity and RR interval features extracted from ventricular activity; 3) detection using SVM classifier based on multi-classification strategy. First, the effectiveness of the feature combination was verified on the MIT-BIH AF database, in which the Acc rate was 92.40%, the Se was 96.25%, the Sp was 88.59%, and the F1 measure was 92.66%. The proposed algorithm was verified in China Physiological Signal Challenge 2018 database, and the results showed that the Se was 85.72%, the Sp was 92.38%, and the F1 measurement was 84.28%, with the Acc reaching 84.38%. It can be seen from the results that this method can effectively detect AF and I-AVB in the ECG signal.

Current self-supervised monocular methods only learn effectively by imposing consistency constraints without relying on any geometric constraints or ground truth depth constraints, which makes the accuracy of the estimation result suboptimal. Compared with the monocular algorithm, the stereo matching network usually follows the geometric process of the traditional stereo algorithm, which makes the estimation result more accurate. Inspired by these findings, we proposed a weakly supervised monocular learning approach that makes use of the disparity maps generated by the self-supervised stereo matching model as the “ground truth” labels to train a self-supervised monocular depth estimation model. To obtain more accurate ground truth labels, we improve the layer of geometry and context in self-supervised deep stereo regression by replacing the 3D convolutional layer with a guided aggregation layer. The design can also reduce computational costs and memory consumption. Then, we build our weakly supervised monocular model by improving the U-Net model and designing a loss function composed of a weakly supervised cost and a self-supervised cost. The estimation results obtained using our model outperform those of the existing self-supervised depth estimation methods under the same training conditions on the challenging KITTI dataset, and the results can easily be generalized to the Cityscapes dataset.

Samples of different initial particle sizes were made by red sandstone collected from Zhuzhou of Hunan Province, and the laboratory tests of slaking were carried out in order to study the influence of samples with different initial particle sizes for disintegration. Then, the distribution of particle size was researched after disintegration during drying–wetting cycles, and the variation rules of slake durability index and fractal dimension were studied based on the tests. Results show that the percentage of each particle group changes along with cycle times, the percentage of each particle group changes along with particle size, and the cumulative percentage of each group changes along with particle size. Changes were all consistent after the samples with different initial particle sizes disintegrating. Meanwhile, the slake durability index has a close exponent correlation with the cycle times. Moreover, the initial particle sizes of samples have a certain influence on the slake durability index and fractal dimension. Bigger the initial particle size of samples is, the smaller the slake durability index will be, and the larger the fractal dimension will be gotten, and the faster the disintegration rate becomes. While the smaller the initial particle size of samples is, the larger the slake durability index will be, and the smaller the fractal dimension will be gotten, and the slower the disintegration rate becomes.

Aiming at the delamination of bricks in powder compacting process, causes of delamination and force analysis on powder compaction are studied. Meanwhile, a mathematics model is established. Based on this model, a measure to reduce the delamination is proposed: increase the compressing velocity and pressure and decrease the raising velocity and height. The sequence of these influential factors is analyzed by orthogonal test. The correctness of the model is verified in the test and a best parameter combination has been put forward. The quality of production and production efficiency can be ensured in the powder compaction.

A homogenized Mg-13Gd-4Y-2Zn-0.5Zr (wt%) alloy was subjected to a repetitive upsetting-extrusion (RUE) process at decreasing temperature from 480 °C to 370 °C. The microstructure and texture development of the alloy during the RUE process was investigated. The results show that average grain size decreases with increasing cumulative strain and decreasing temperature. Uniform ultrafine-grain structure with an average grain size of 3.4 μm is achieved after 6 passes, i.e., cumulative strain of 8.4. Grain refinement is induced by a complicated combination of discontinuous dynamic recrystallization(DDRX) and continuous dynamic recrystallization(CDRX). Kink of lamellar long period stacking order (LPSO) phases play an important role in the grain refinement through subdividing the coarse grains by inducing recrystallization evolved in the kink bands. After 1 pass of RUE, a strong basal texture is obtained. With increasing RUE passes, the texture is gradually weakened, which results from cooperative effect of dynamic recrystallization(DRX) and the alternative change of loading directions (axial and radial) during RUE processing.

Cyclic expansion extrusion with an asymmetrical extrusion cavity (CEE-AEC) was carried out on pure magnesium up to 3 passes at different deformation temperatures of 250 °C and 350 °C. The microstructure and texture evolution of its edge and center regions are studied respectively, and their mechanical properties are correlated. The results show that there is an incomplete dynamic recrystallization (DRX) region in pure magnesium deformed at 250 °C. Therefore, pure magnesium processing at 250 °C has a larger grain size and higher texture strength than that processing at 350 °C. According to the tensile test, the ultimate tensile strength (UTS) of different positions of different temperatures is very close because the DRXed grains grow at 350 °C. But the value of tensile yield strength (TYS) is nearly doubled, the main reasons are that the effect of (0001) basal slip and texture softening is greater than that of grain refinement.

Oreolalax rhodostigmatus Hu and Fei, 1979 is a rare and threatened frog, which is mainly distributed in the caves or underground waters in karst regions of southwest China. The International Union for Conservation of Nature (2017) categorized this endemic species as vulnerable. In this study, we reported the first complete mitochondrial genome of O. rhodostigmatus. The circular double-strand genome was 18,676 bp in size and contained 13 protein-coding genes, 23 transfer RNA genes, 2 ribosomal RNA genes, and a putative control region. The overall nucleotide composition was: 28.0% A, 32.4% T, 24.9% C, and 14.7% G, with a total A+T content of 60.4%. The common genomic features including genome content, gene order, and composition were similar to those of other Oreolalax species. Phylogenetic analysis of 17 Megophryidae species indicated that O. rhodostigmatus was located in the basal clade of Oreolalax.

Triplophysa brevibarba is distributed in the upstream of Ya-lung River. The conservation status of this fish has been assessed as near threatened due to overfishing and habitat destruction. In the present study, we determined the first complete mitochondrial genome of T. brevibarba. This genome was 16,570 bp in size and contained 13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes, and a typical control region. The overall nucleotide composition was: 28.2% A, 28.5% T, 25.3% C, and 18.0% G, with a total A + T content of 56.7%. The genome size, gene arrangement, and composition were similar to those of other Triplophysa species. Phylogenetic analysis of all 42 Nemacheilidae species showed that Triplophysa is a monophyletic group and T. brevibarba was clustered with Triplophysa minxiannesis and Triplophysa robusta located in the basal clade of Triplophysa.

Background: Brefeldin A (BFA) has been known to induce endoplasmic reticulum stress (ERS) and Golgi body stress in cancer cells. ERGIC3 (endoplasmic reticulum-Golgi intermediate compartment 3) is a type II transmembrane protein located in the endoplasmic reticulum and Golgi body. ERGIC3 over-expression is frequently observed in cancer cells. Objective: In this study, we aim to explore whether BFA administered concurrently with ERGIC3 silencing would work additively or synergistically inhibit cancer cell growth. Methods: ERGIC3-siRNA was used to knock-down the expression of ERGIC3 and BFA was used to induce ERS in lung cancer cell lines GLC-82 and A549. Q-RT-PCR and Western Blot analysis were used to detect the expression of ERGIC3 and downstream molecules. GraphPad Prism 6 was used to quantify the data. Results: We demonstrated that silencing of ERGIC3 via siRNA effectively led to down-regulation of ERGIC3 at both mRNA and protein levels in GLC-82 and A549 cells. While BFA or ERGIC3- silencing alone could induce ERS and inhibit cell growth, the combination treatment of lung cancer cells with ERGIC3-silencing and BFA was able to additively enhance the inhibition effects of cell growth through up-regulation of GRP78 resulting in cell cycle arrest. Conclusion: ERGIC3 silencing in combination with BFA treatment could additively inhibit lung cancer cell growth. This finding might shed a light on new adjuvant therapy for lung adenocarcinoma.

Here we investigate the two-parameter high-frequency localization for the eigenfunctions of a Schr��dinger operator with a singular inverse square potential in high-dimensional balls and spherical shells as the azimuthal quantum number $l$ and the principal quantum number $k$ tend to infinity simultaneously, while keeping their ratio as a constant, generalizing the classical one-parameter localization for Laplacian eigenfunctions [SIAM J. Appl. Math. 73:780-803, 2013]. We prove that the eigenfunctions in balls are localized around an intermediate sphere whose radius is increasing with respect to the $l$-$k$ ratio. The eigenfunctions decay exponentially inside the localized sphere and decay polynomially outside. Furthermore, we discover a novel second-order phase transition for the eigenfunctions in spherical shells as the $l$-$k$ ratio crosses a critical value. In the supercritical case, the eigenfunctions are localized around a sphere between the inner and outer boundaries of the spherical shell. In the critical case, the eigenfunctions are localized around the inner boundary. In the subcritical case, no localization could be observed, giving rise to localization breaking., 24 pages, 5 figures

With the progress of human space technology, mankind stepped into more distant space. Due to the long distance from the earth in deep space exploration, higher requirements were put forward for intelligent cognition of targets and environment. In this paper, the space target classification and recognition technology based on deep learning was studied by taking the classification of three types of satellites as an example. A satellite simulation sample set for deep learning was established, and a ResNet multi-layer convolutional neural network model suitable for spatial target characteristics was constructed. The training and test of satellite intelligent classification were completed, and the feature extraction results of the neural network were visualized. The accuracy rate of satellite classification identification for the remote sensing satellites, communication satellites and navigation satellites reached 90%, which provided a reference for the development of intelligent classification and identification technology of space targets in the field of deep space exploration.

The Al–0.78Mg–0.69Si–0.11Ce–0.06La aluminum alloy rod was prepared by ultrasonic-assisted continuous casting and rolling process, and the effects of ultrasonic treatment on the microstructure, electrical conductivity, and tensile properties of the continuous casting billet and the continuous casting and rolling rod were investigated. The results showed that ultrasonic treatment could purify, homogenize, and refine the aluminum alloy liquid, eliminate the coarse dendrite of continuous casting billet, restrain the element segregation, and significantly improve the strength, plasticity, and conductivity of the aluminum alloy rod. When the ultrasonic frequency was 20 kHz and the power was 300 W, the tensile strength, elongation, and electrical conductivity of the aluminum alloy rod were 214.5 MPa, 9.6%, and 55.9% IACS, respectively. Compared with the continuous casting and rolling aluminum alloy rod without ultrasonic assistance, the tensile strength, elongation, and conductivity were increased by 13.6, 41.2, and 2.4%, respectively.

Motivated by Kyprianou and Zhou (2009), Wang and Hu (2012), Avram et al. (2017), Li et al. (2017) and Wang and Zhou (2018), we consider in this paper the problem of maximizing the expected accumulated discounted tax payments of an insurance company, whose reserve process (before taxes are deducted) evolves as a spectrally negative L��vy process with the usual exclusion of negative subordinator or deterministic drift. Tax payments are collected according to the very general loss-carry-forward tax system introduced in Kyprianou and Zhou (2009). To achieve a balance between taxation optimization and solvency, we consider an interesting modified objective function by considering the expected accumulated discounted tax payments of the company until the general draw-down time, instead of until the classical ruin time. The optimal tax return function together with the optimal tax strategy is derived, and some numerical examples are also provided.

This study investigates the effects of long-period stacking order (LPSO) phases on the dynamic recrystallization (DRX) process. By comparing Mg-Gd-Y-Zn-Zr (GWZ) alloy and Mg-Gd-Y-Zr (GW) alloy deformed by 4 passes of Isothermal Reciprocating Upsetting-Extrusion (RUE), the initial alloy grain sizes are 113.4 μm and 88.2 μm, respectively, after 4 passes, the grain size becomes 3.5 μm and 4.8 μm, and the grain refinement of GWZ is greater. After 1 pass, the DRX volume fraction of GWZ alloy is 83% and 15%, which is related to the LPSO phases contained in the GWZ alloy. The texture strength of the GWZ alloy ranges from 8.5 of 1 pass to 2.2 of 4 passes, while the GW alloy is from 5.9 of 1 pass to 2.8 of 4 passes, mainly due to the DRX grain volume fraction. The tensile test results at room temperature (RT) showed that the ultimate tensile strength (UTS) and tensile yield strength (TYS) of GWZ alloy are higher than that of GW alloy, and the elongation is lower than that of GW alloy.

An accurate hierarchical stereo matching method is proposed based on continuous 3D plane labeling of superpixel for rover’s stereo images. This method can infer the 3D plane label of each pixel combined with the slanted-patch matching strategy and coarse-to-fine constraints, which is especially suitable for large-scale scene matching with low-texture or textureless regions. At every level, the stereo matching method based on superpixel segmentation makes the iteration convergence faster and avoids huge redundant computations. In the coarse-to-fine matching scheme, we propose disparity constraint and 3D normal vector constraint between adjacent levels through which the disparity map and 3D normal vector map at a coarser level are used to restrict the search range of disparity and normal vector at a fine level. The experimental results with the Chang’e-3 rover dataset and the KITTI dataset show that the proposed stereo matching method is efficiently and accurately compared with the state-of-the-art 3D labeling algorithm, especially in low-texture or textureless regions. The computational efficiency of this method is about five to six times faster than the state-of-the-art 3D labeling method, and the accuracy is better.

Bruton's tyrosine kinase (BTK), a non-receptor tyrosine kinase, is a member of the Tec kinases family and is essential for B cell receptor (BCR) mediated signaling. BTK inhibitors such as ibrutinib hold a prominent role in the treatment of B cell malignancies. Here we disclose a potent, selective, and covalent BTK inhibitor, HZ-A-005, currently in preclinical development. HZ-A-005 demonstrated dose-dependent activity in two xenograft models of lymphoma in vivo. It showed highly favourable safety, pharmacokinetic (PK), and pharmacodynamic (PD) profiles in preclinical studies. On the basis of its potency, selectivity, and covalent mode of inhibition, HZ-A-005 reveals the potential to be a promising BTK inhibitor for a wide range of cancer indications.

Al-12Zn-2.4Mg-1.2Cu (wt%) alloy billets as-deposited were extruded to be Φ100 mm bar, Φ100 mm × lΦ 80 mm seamless pipe and 160 mm × l15 mm stripper plate under different deformation ways. The microstructures of the products as-heat-treated were studied by optical metallographic and scanning electron microscope, and the mechanical properties were also measured. Metallographic microstructures show that the grains in the initial billets are almost equiaxed with diameter about 20 μm. There are some second phases precipitated distributing in the grains and on the grain boundary. The deposited ventages around the grains as-deposited were welded together by a welding metallurgy way during extrusion process. The flow lines were clearly observed in the extrusion direction in all different extruded products. For the products as-heat-treated, the tensile strengths, the yield strengths and the elongations of the bars are 688 MPa, 654 MPa and 12% in the cross direction (CD), while 698 MPa, 674 MPa and 10.5% in the longitude direction (LD); for the plates they are 783 MPa, 748 MPa and 7% in CD; while 751MPa, 719 MPa, and 8% in LD; for the pipes they are 781 MPa, 735 MPa and 9% in LD. Scanning electron microscope examination reveals the fracture characteristics of the fractured specimens exhibit three different fracture models which are ductile fracture, mixed fracture and brittle fracture corresponding to bars, pipes and plates, respectively.

The axial split-flow forming can be used to improve the metal flow and effectively reduce the forming force of large complex components. In this paper, in order to figure out the axial split-flow characteristics in the plastic forming, the flow regularity of the each deformation area in the material during the process of split-flow forming is studied based on the classical plasticity theory, the relationship between the split-flow area radius and the geometric parameters of the mold, and blank is analyzed with the analytic method of plastic mechanics, and a mathematical model for the split-flow area radius is built. The test shows that the model can be used to provide a theoretical reference to the accurate design on the axial split-flow forming of blank. Based on the energy theory and considering the complex coefficient, a mathematical model for the forming force of the axial split-flow forming unit is built. With a comparison among the forming experiments and finite element simulation analyses under different temperatures, the gray correlation degree between the model and the practical data in the experiment is 0.91, higher than 0.83 got by the traditional method. The developed model can reduction of the time in the preform optimization process and improvement the accuracy of forming force calculate in axial flow-split forming process. The result of this work can be used to theoretical guidance for practical engineering application of preforming and optimal design in axial split-flow precision forming.