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Face anti-spoofing (FAS), as an important means to protect face recognition models, can ensure that the system remains secure and reliable in the face of various presentation attacks. The current deep learning-based face anti-spoofing model has satisfactory results when the test data and training data obey the same distribution, but the accuracy of the model decreases considerably when the trained model infers in the scene outside the domain, such as cross-domain transfer and out-of-distribution scenarios. The problems that silent face anti-spoofing models will encounter in real scenarios, i.e., the models encounter unknown environments and unknown attack methods, are mainly described. The corresponding solutions are classified into four categories: methods based on domain adaptation, methods based on domain generalization, methods based on zero shot or few shot learning, and methods based on anomaly detection. Each solution and its deep learning model methods are summarized and compared. The mechanism, network structure, advantages, limitations and application scenarios of some major methods are summarized. After that, common public datasets, evaluation metrics, measurement protocols commonly used for face anti-spoofing in out of domain scenarios and test results of state-of-the-art methods under some protocols are introduced. Finally, the difficulties and challenges of face anti-spoofing in practical applications are discussed, and future research directions are summarized.

In order to solve the problem of poor consistency between the traditional super-resolution image quality assessment (SRIQA) index and human subjective perception, this paper presents a reference free super-resolution image quality evaluation method by using multi-layer perceptron (MLP). This method used the pre trained VGG16 network to extract the perceptual quality features of the super-resolution image, and established the regression model between the perceptual quality features of the super-resolution image and the corresponding subjective quality score through MLP. Experimental results show that the Pearson linear correlation coefficient (PLCC) and Spearman rank order correlation coefficient (SROCC) of the proposed algorithm on the public super-resolution image data set exceed 0.95, which is significantly superior to other existing image quality evaluation methods, and has higher consistency with human subjective perception.

Far-range rendezvous problem of geosynchronous orbit is studied based on the linear equation of near-circular deviation, and a two-layer nonlinear programming model is established based on the in-plane 3-pulse manuveur strategy. In the outer layer, the particle swarm optimization algorithm is used to optimize the arugment angle of the first and second pulses, which improves the traditional method of fixing at apogee or perigee. After determining the arugment angle of the first pulse and the second pulse, the inner layer uses the near-circular deviation linear equation to solve the arugment angle of the third pulse and the speed increment of the three pulses quickly. Simulation results show that the proposed planning method can reach the designated terminal in the specified time with less fuel cost, and has engineering application value. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects and mechanisms of exogenous calcium-binding protein S100A4 on proliferation, survival and migration functions of glioma cells. Methods: Pan-cancer dataset was downloaded from UCSC database for the analysis of S100A4 expression and prognosis in pan-cancer, and transcriptome and clinical data of glioma patients were downloaded from CGGA database. Prognosis and progression of S100A4 expression in glioma patients were analyzed by R software. S100A4 protein network interaction of glioma patients were addressed by online analytical tools GEPIA and STRING. Human glioma cell lines (U87 and U251) were cultured in vitro, and the experiment was divided into 3 groups: PBS group, S100A4 group and S100A4+TAK242 group [Resatorvid (TAK242) was a specific inhibitor of Toll-like receptors 4 (TLR4)]. Flow cytometry was used to detect proliferation and apoptosis of glioma cells. Wound healing assay, Transwell assay and clone formation assay were used to detect migration and proliferation ability of U87 and U251 cells, and Western blot was used to detect levels of TLR4 protein and NF-κB related signaling proteins. Results: Bioinformatics results showed that S100A4 was significantly upregulated in multiple tumours (P<0.05), which included glioblastoma (GBM), lower grade glioma (LGG), stomach adenocarcinoma (STAD), liver hepatocellular carcinoma (LIHC), etc, with poorer prognosis in GBM and LGG. Compared with glioma patients with low expression of S1004, high expression S100A4 in glioma patients had shorter survival and higher degree of WHO classification. In addition, S100A4 protein in glioma patients may interact with Annexin A2 (ANXA2), TLR4 and advanced glycosylation end product-specific receptor (AGER) proteins. In cellular experiments, U87 and U251 cells showed enhanced proliferation and migration, and significantly up-regulated levels of TLR4, p-ERK1/2, p-p38 and p-p65 proteins after exogenous S100A4 treatment compared to PBS group (P<0.05), while glioma cells in S100A4+TAK242 group showed weaker proliferation and migration, and lower TLR4, p-p38 and p-p65 protein levels than those in S100A4 group, TLR4, p-ERK1/2, p-p38, p-p65 protein levels were significantly down-regulated (P<0.05). Conclusion: S100A4 may regulate function of glioma proliferation, migration and survival through TLR4/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

As a countermeasure to the problem of brittleness of seawater sea sand concrete (SSC), volumetric admixture of glass fiber (GF) and polyvinyl alcohol (PVA) fiber was used as variable, the corresponding specimens were prepared, and the cube compressive strength, splitting tensile strength, axial compressive strength, and elastic modulus were tested. The microstructure of fiber reinforced seawater sea sand concrete was analyzed by scanning electron microscope (SEM) scanning and energy dispersive spectroscopy (EDS) dot scanning, and a model was established based on the grey system theory. The research results show that the fiber can effectively reduce the formation of cracks, leading to a ductile failure of the specimen. In general, the mechanical properties of mixed fiber were improved better than that of single fiber, and the hybrid ratio 2:1 brings a improvement of 24. 2% and 38. 8% for the compressive strength and splitting tensile strength, respectively. The hybrid ratio of 1:1 increases the axial compressive strength and elastic modulus by 34. 5% and 15. 5%. It was observed by SEM and EDS that fiber incorporation could densify the matrix, while the main disadvantage of SSC was that the salt crystallization generated by corrosive ions and swelling substances weakened the bond between aggregate and mortar, resulting in defects of interfacial transition zone (ITZ) . The established NSGM(1, 3) model has a high accuracy, the accuracy reaches class II and conforms to the long-term prediction, which provides a favorable basis for the study of the strength evolution of fiber reinforced seawater sea sand concrete. [ABSTRACT FROM AUTHOR]

To study the applicability of solid waste replacement of concrete raw materials and the effect on concrete properties, through the orthogonal test of 16 groups of fly ash-silica manganese slag recycled concrete test blocks, the effects of fly ash volume substitution for cementitious material, silicon manganese slag volume substitution for sand, and recycled aggregate mass substitution for coarse aggregate on concrete slump, cube compressive strength and splitting tensile strength were studied under different substitution amounts. The results show that when the substitution amount of fly ash is 40% (volume fraction), the increasing rate of concrete slump is the largest, which is 14. 5%, and the cube compressive strength and splitting tensile strength are reduced, and the reduction rate are 7. 2% and 22. 8%, respectively. The substitution of silicon manganese slag reduces the slump of concrete, and when the substitution amount of silicon manganese slag is 80% (volume fraction), the reduction rate of the compressive strength and splitting tensile strength is the smallest, which are 0. 5% and 11. 5%, respectively. The substitution of recycled aggregate reduces the slump of concrete, and when the substitution amount of recycled aggregate is 100% (mass fraction), the reduction rate of the cube compressive strength is 1. 9%, and the reduction rate of splitting tensile strength is 12. 4%. The cube compressive strength of concrete is predicted by the optimized model NSGM(1,4). The average relative error of model simulation is 0. 542%, and the average relative error of model prediction is 2. 727%. [ABSTRACT FROM AUTHOR]

Objective The variations in T cell subset composition and levels of inflammatory cytokines and acetylcholine receptor (AChR) antibody during the interval for myasthenia gravis (MG) patients were evaluated to investigate regulatory roles of in the pathogenesis of MG. Methods Thirty patients with MG and 20 healthy controls (HCs) were recruited. Flow cytometry was employed to detect the frequencies of CD4 + T cells, CD8 + T cells, central memory T cells (CD4 + CD45RO + CCR7 + , Tcm), effector memory T cells (CD4 + CD45RO + CCR7 - , Tem), follicular helper T cells (CD4 + CXCR5 + , Tfh) and follicular regulatory T cells (CD4 + CXCR5 + FOXP3 + , Tfr) in the peripheral blood. The levels of interleukin 2(IL-2), IL-4, IL-12, IL-17 and interferon γ (IFN-γ) in the peripheral blood were determined by cytometric beads array (CBA). The levels of IL-7 and anti-AChR antibody were measured with ELISA. Results No obvious differences were observed in the frequencies of Tfh, Tem, CD8 + T cells and CD4 + T cells, and the ratio of CD4/CD8 in the peripheral blood of MG patients, compared with HCs. MG subjects presented notably decreased frequencies of Tcm and increased frequencies of Tfr compared with HCs. In addition, elevated levels of IL-2, IL-4, IL-12, IL-17 and IFN-γ and lowered levels of IL-7 were observed in the plasma of MG individuals, compared with HCs. No significant correlations were found among the levels of cytokines and frequencies of T cell subsets. No significant changes were found in AChR antibody levels. Conclusion The results suggest a unique spectrum of the memory T cells and follicular T cells, together with a unique cytokine profile in the MG individuals during treatment.

Many risk factors lead to hypohepatia and hepatic failure, causing people suffering from end-stage liver disease. The conventional treatment for end-stage liver disease is not good enough. Orthotopic liver transplantation is effective. However, the high cost, lack of liver source, immune rejection and other factors limit the large-scale clinical application. Thus, cell therapy is a good option. Studies on common cell sources for the treatment of liver disease and the induction of hepatocytes by embryonic stem cells or pluripotent stem cells have made progress. With the development of stem cell technology, cell transplantation has become a new option, which brings hope to people with end-stage liver diseasetransplantation has become a new option. It brings hope to people with end-stage liver disease.

Purpose: Calcium phosphate activity coating containing different contents of zinc was deposited onto the surface of pure titanium modified by plasma electrolytic oxidation. The physical and chemical properties of different contents of zinc were compared among three groups, and the influence on antibacterial activity of P.gingivalis (Pg) and A.actinomycetemcomitans (Aa) was evaluated., Methods: Pure titanium samples were treated in the electrolyte of plasma electrolytic oxidation with 0.08 mol/L calcium and 0.06 mol/L phosphorus, and 0.01, 0.03, 0.05 zinc was added to each group in order to deal with pure titanium plate. Titanium samples were divided into three groups: low, middle and high group according to zinc contents. The group without zinc was as control. The binding force of coating and titanium was tested by electric universal test machine. The topography of surfaces was observed under scanning electron microscope (SEM). The crystalline structure of surfaces was determined by XRD. The chemistry and elements of surfaces were determined by XPS. Pg and Aa were seeded onto samples surfaces, and the antibacterial properties of four kinds of materials were evaluated by using scanning electron microscopy and the paster method. Statistical analysis was performed using SPSS 13.0 software package., Results: It was found that the aperture and roughness were increased with the increase of content of zinc. The crystallization of low zinc group was superior to high zinc group. The content of HA and Zn3P2 in low zinc group was more, but ZnO in high zinc group was more. Scanning electron microscope demonstrated that the number of Pg and Aa decreased on the surface with the increase of the content of zinc, while the bacteria of high zinc group underwent lysis and necrosis. By using the paster method, the number of Pg and Aa decreased on the surface with the increase of the content of zinc, and there was significant difference among the four groups., Conclusions: The change of zinc content will change the physical and chemical properties of the coating; at the same time, the antimicrobial property of calcium phosphate coating with high content zinc was the best.

Estrogen-related receptor a (ERRalpha) is a key regulator for energy metabolism and adipogenesis. However, its role in lipolysis is unknown. To study the function of ERRalpha in lipolysis, primary cultured differentiated porcine adipocytes were treated by a specific inverse agonist XCT790 or infected with adenoviral vector expressed ERRalpha for 48 h, in the absence and/or presence of specific protein kinase A (PKA) inhibitor or extracellular signal-related kinase (ERK) inhibitor. Then, we measured the triglyceride (TG) content and the glycerol release into the culture media to analysis the effect of ERRalpha on lipolysis; Further, we analyzed the expression of PPARgamma, perilipin A, p-perilipin A, HSL and ATGL with Western blotting. Here, we found that ERRalpha significantly increased adipocytes differentiation, TG accumulation and glycerol release. Separately or simultaneously block the PKA and ERK pathway do not significantly altered the effect of ERRalpha on glycerol release. ERRalpha significantly up-regulated the proteins expression of PPARgamma, perilipin A, HSL and ATGL, while the p-perilipin A protein level was not significantly changed. These findings imply that ERRalpha could increase lipolysis via up-regulating HSL and ATGL, thereby to supply more FFA as substrate for a larger turnover of cellular triglyceride pool during adipocytes differentiation.

Estrogen-related receptor alpha (ERR alpha) is an orphan nuclear receptor and functions as a key regulator of energy metabolism in high energy demand tissues. However, its role in white adipose tissue is largely unknown. In this study, we aim to clone the ORF sequence of pig ERR alpha with touch down-PCR, analyze the expression pattern of ERR alpha protein and its subcellular localization with Western blotting and cell immunofluorescence method respectively, and identify the effect of ERR alpha on lipid accumulation in mature porcine adipocytes with its specific inhibitor XCT790. The results showed that the ERR alpha ORF sequence is 1269 bp (GenBank Accession No. FJ446485, not published), and encode 422 amino acids. The homologies of ERR alpha nucleotide and amino acids sequences are high in different species. ERR alpha protein is highly expressed in pig white adipose tissue, kidney and heart, while remarkably lower in spleen. Cell immunofluorescence results indicated that ERR alpha protein distribute widely in adipocytes nucleus and cytoplasm. XCT790 significantly inhibited the expression of ERR alpha and lipid accumulation in porcine mature adipocyte. This study will provide new target and theoretical reference for fat deposition control.