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To extract the high-quality DEM in complicated mountain areas, a DEM fusion method for ascending and descending orbit StereoSAR DEMs considering Synthetic Aperture Radar (SAR) echo intensity is proposed. After the analysis for the influence of terrain features and SAR side-looking imaging characteristics on radar echo intensity and DEM accuracy, four TerrasAR-X images with the stripmap mode and the 3 m spatial resolution covering a certain area of Maoxian County, Sichuan Province, China, was selected as the experimental area. StereoSAR technology was used to extract the ascending orbit StereoSAR DEM and the descending orbit StereoSAR DEM, respectively, and the corresponding radar echo intensity map was calculated. Then, while comparing the radar echo intensity corresponding to the same point position, DEM fusion was carried out, and the accuracy of DEM before and after the fusion was analyzed with the ground points measured by GNSS-RTK as reference data. Finally, a high-quality DEM with a 3 m spatial resolution in the experimental area was obtained. The DEM accuracy was improved on all slopes, and the mean absolute deviation (MAD) improved to 4.798 m, the standard deviation (SD) improved to 6.087 m and the LE90 improved to 40.48 m. The experimental results indicate that the fusion method of high-resolution ascending and descending orbit StereoSAR DEMs considering SAR echo intensity can effectively extract DEM with high accuracy and reliability, which can provide technical support for obtaining high-quality terrain information in similar areas.

BACKGROUND The present study aimed to investigated the expression pattern of long noncoding RNA LINC00858 (LINC00858) in gastric cancer (GC) patients and its feasibility as a new prognostic biomarker. METHODS We examined LINC00858 expression in GC tissues and matched normal tissues from 189 patients using a quantitative reverse transcription-polymerase chain reaction. The correlations of LINC00858 levels in GC patients with clinicopathologic features were analyzed using a chi-squared test. The influence of LINC00858 on the overall survival rate of GC patients was precisely calculated using Kaplan-Meier methods (log rank tests). Multivariate Cox regression assays were carried out for the identification of the independent risk factors for GC. RESULTS We observed that LINC00858 was distinctly up-regulated in GC tissues compared to adjacent non-tumor specimens (p < 0.01). Higher expression of LINC00858 in GC was found to be associated with TNM stage (p = 0.003) and lymphatic metastasis (p = 0.007). Using Kaplan-Meier assays, we found that patients with high expression levels of LINC00858 had a distinctly poor overall survival and disease-free survival compared to those with low expression levels of LINC00858 (p = 0.0102). Multivariate analyses confirmed that LINC00858 (p < 0.05) was an independent prognosis factor for GC patients. CONCLUSIONS The data obtained in our study indicate that LINC00858 may be used as a novel prognostic indicator in GC patients.

Polymorphisms in the tumor necrosis factor α (TNF-α) gene are emerging as key determinants of gastric diseases. The TNF-α-238G/A single-nucleotide polymorphism (SNP) is the most extensively studied. However, this association is inconsistent amongst different populations. We therefore conducted an updated meta-analysis to obtain a more precise estimate of the association of TNF-α-238G/A polymorphism with gastric cancer (GC) risk. A comprehensive search of PubMed, Embase, Chinese (CNKI and WanFang) databases was performed to identify relevant studies through 5 May 2018. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of the association. Fourteen studies were included in our meta-analysis involving 2999 cases and 4685 controls. There was no significant association between TNF-α-238G/A polymorphism and GC risk in the overall populations. In the subgroup analysis, we found that TNF-α-238G/A polymorphism was associated with the increased risk of GC amongst Asians, especially in Chinese, but not in Caucasians. Subgroup analysis by genotyping methods revealed increased risk for other methods. In conclusion, our present meta-analysis shows that TNF-α-238G/A polymorphism is associated with the risk of GC in East Asian individuals.

Gastric cancer (GC) is one of the most common types of cancer in humans and the second leading cause of cancer-associated mortality worldwide. Identifying novel risk factors will facilitate the development of therapeutic strategies to prevent and treat GC. Increased expression of the Src homology 2 B adaptor protein 1 (SH2B1) may stimulate the malignant progression of lung cancer, esophageal cancer and neuroblastoma. However, its function in GC has not yet been investigated. To identify whether increased serum SH2B1 is a risk factor for GC, the present study performed a nested case-control study of patients within the Chinese cohort study. Levels of serum SH2B1 were measured in 563 patients diagnosed with GC during the follow-up period and in 1,126 matched healthy controls. The results demonstrated that high levels of serum SH2B1 were associated with an increased GC risk (odds ratio, 3.23; 95% confidence interval, 2.45-5.65). When analyses were stratified further by sex, age and smoking, an association between increased levels of SH2B1 and GC was identified in males but not in females. Furthermore, the association between SH2B1 levels and GC was more evident in younger than in older participants, and statistically significant in current smokers but not in nonsmokers. These results were not altered following the exclusion of outliers. Furthermore, it was demonstrated that overexpression of SH2B1 contributes to the malignant transformation of normal gastric epithelial cells. Thus, the present study demonstrated that elevated serum SH2B1 levels may increase the risk of GC.

A 3D Finite Element Model of the Temperature Field for Electron Beam Cladding of Pre-Tungsten Powder on the Surface of the Copper Block was Established, According to the Actual Situation of the Electron Beam Cladding Process, Based on Finite Element Analysis Software ANSYS Workbench, Analyzed the Temperature Field Distribution of the Electron Beam Cladding Process. Temperature Field Calculation Results Showed that the Cladding Process Heating and Cooling Speed was up to 103-104°C/s, and the Surface Temperature Increased Rapidly, while the Temperature of the Substrate Maintained Low, since the Water Cooling System.

Gastric cancer (GC) is one of the most common human cancers and the second leading cause of cancer-related mortality worldwide. The major cause of death is metastasis. Elucidating molecular mechanism of metastasis in gastric cancer will help us to further understand the pathogenesis and progression of the disease, and offer new targets for effective therapies. In this study, we found that SH2B1 overexpression promoted invasion, migration and anoilds resistance and silencing it inhibited invasion, migration and anoilds resistance in gastric cancer SGC-7901 cells. However, over-expressing or silencing it did not affect proliferation in the cells. miR-874 could degrade SH2B1 by targeting its 3’UTR and was negatively associated with metastasis traits in SGC-7901 cells. Its overexpression inhibited proliferation in the cells. Thus, we concluded that miR-874 inhibits metastasis-relevant traits via targeting SH2B1 in gastric cancer SGC-7901 cells.

Cancer initiating cells (CIC) are defined as the unique subpopulation in the tumors that possess the ability to initiate tumor growth and sustain self-renewal as well as metastatic potential. In this study, we found that EHF overexpression promoted formation of CIC traits and silencing it inhibited the traits in gastric cancer NCI‑N87 cells. Overexpressing EHF downregulated the antitumor effect of 5-fluorouracil (5-FU) in NCI‑N87 cells. We found that miR‑206 downregulated EHF protein expression by targeting its 3'UTR in NCI‑N87 cells and GES-1 cells. Overexpressing miR‑206 inhibited formation of CIC in NCI‑N87 cells. In gastric cancer tissues, EHF protein expression was upregulated and miR‑206 was downregulated. We identified a negative correlation between EHF protein and miR‑206 expression in gastric cancer tissues. Thus, we concluded that miR‑206 inhibits formation of CICs by targeting EHF in gastric cancer.

Through introduction of the principle and characteristics of electron beam machining technology, the application status and application instance of electron beam in research of materials science and materials processing in recent years were introduced in detail. The research situation of the previous various electron beam machining methods and applications was discussed, and the various research results were analyzed, thus concluded that the emphasis and advantages of the electron beam machining technology in the application of various materials.

Through introduction of meso-damage theory and application situation in recent years, the related categories and mechanism of meso-damage were analyzed. The previous research on the application of the meso-damage of various materials was discussed and various research results analyzed. The emphasis and advantages of meso-damage theory in material application were concluded.

Aiming at high voltage electrostatic field of melting electron beam gun system, taking 30 kv 60 kw melting electron beam gun for example, the structure of the electric field and boundary conditions was designed. And the mathematical model of the electric field was established. The method of numerical calculation was used to solve the mathematical model, and Matlab software was used to simulate the equipotential lines of the electric field. The electrolytic cell experiment was used to simulate high voltage electrostatic field distribution of the electron beam system. At the same time compared with the two different results, the reasons and the improved method were analyzed. For research and calculation high voltage electrostatic field of processing equipment such as electron beam welding, melting, etc, offers a more general analysis, design and calculation methods.

This paper researched the high press and broken drift deformation mechanism of 1424m filling roadway by theoretical analysis and on-site monitoring. Strengthening rock residual strength by improving roadway pressure contributed to enhancing drift stability. The roadway deformation could be controlled effectively with the method of improving rock self-carrying capacity. The monitoring results showed anchor supporting resistance and reinforcement depth were inadequate. And supporting method was not coordinate with rock deformation, which was the main reason of roadway deformation increasing gradually. Improving bolt pre-stress and increasing the anchoring range are the key to limit roadway deformation. And the support way should provide a greater supporting resistance. It recommends that the combination reinforcing method, "strong prestressed anchor + long cable+ grouting behind the surrounding rock" is appropriate for controlling the drift displacement, and it can save supporting costs 390 yuan per year for per meter drift compared with previous supporting way while reaching the same effect.

Response surface methodology (RSM) using the central composite rotatable design (CCRD) model was used to optimize the formulation of paclitaxel (PTX)-cepharanthine (CEP) nanoparticles for gastric cancer.Nanoparticles were prepared using nanoprecipitation technique and optimized using central composite rotatable design response surface methodology (CCRD-RSM). Further the optimized nanoparticles were characterised for particle size (PS), zeta potential, entrapment efficiency (EE), drug loading efficiency (DL), anticancer potential against MKN45 (human gastric cancer) cells, in vivo tumor inhibition and survival analysis.Significant findings were the optimal formulation of polymer concentration of 48 mg, surfactant concentration of 45% and EE of 98.12%, DL of 15.61% and mean diameter of 198±4.7 nm. The encapsulation of PTX/CEP into nanoparticles retained the synergistic anticancer efficiency against MKN45 cells. In the in vivo evaluation, PTXsCEP nanoparticles delivered into mice by intravenous injection significantly improved the antitumor efficacy of PTX/CEP. Moreover, PTX/CEP co-loaded nanoparticles substantially increased the overall survival in an established MKN45-transplanted mouse model.These data are the first to demonstrate that PTX/CEP co-loaded nanoparticles increased the anticancer efficacy in cell lines and xenograft mouse model. Our results suggest that PTX/CEP coloaded nanoparticles could be a potential useful chemotherapeutic formulation for gastric cancer.

This paper considers eigenstructure assignment (ESA) in high-order descriptor linear systems via output feedback. Parametric expressions for the left and right closed-loop eigenvectors associated with the finite closed-loop eigenvalues and two simple and complete parametric solutions to the feedback gain matrix are obtained on the basis of the parametric solution to the generalized high-order Sylvester matrix equation. This approach does not impose any restriction on the closed-loop eigenvalues. The numerical example illustrates the effectiveness of the proposed approach.

This paper considers parametric control of high-order descriptor linear systems via proportional plus derivative feedback. By employing general parametric solutions to a type of so-called high-order Sylvester matrix equations, complete parametric control approaches for high-order linear systems are presented. The proposed approaches give simple complete parametric expressions for the feedback gains and the closed-loop eigenvector matrices, and produce all the design degrees of freedom. Furthermore, important special cases are particularly treated. Based on the proposed parametric design approaches, a parametric method for the gain-scheduling controller design of a linear time-varying system is proposed and the design of a BTT missile ai]topilot is carried out. The simulation results show that the method is superior to the traditional one in sense of either global stability or system performance.

This paper considers eigenstructure assignment in high-order linear systems via output feedback. Parametric expressions for the left and right closed-loop eigenvectors associated with the finite closed-loop eigenvalues and two simple and complete parametric solutions for the feedback gain matrices are obtained on the basis of the parametric solutions of the generalized high-order Sylvester matrix equations. This approach does not impose any restrictions on the closed-loop eigenvalues. An illustrative example shows the effect of the proposed approach. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society

New criteria for impulsive-mode controllablizability of descriptor linear systems are proposed by adopting the null space approach. The range of the possible dynamical orders of the closed-loop system with impulsive-mode controllability is characterized in terms of the original system matrices. Moreover, the parametric expressions of the impulsive-mode controllablizing controllers are also established. Since only the orthogonal transformations are involved, the design approach is numerically stable. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society

We report our experience of diagnosing and treating hepatic angiomyolipoma (HAML), a rare benign mesenchymal tumor.We analyzed retrospectively the clinicopathologic, radiological, and operative data of 25 patients who underwent surgery for HAML at our institute between November 2001 and May 2006.Most patients (20/25) were asymptomatic and had normal liver function. Ultrasonography (US) showed a heterogeneous hyperechoic mass in 13 of 23 patients, precontrast computed tomography (CT) showed that all of 12 lesions scanned were hypodense, and magnetic resonance imaging (MRI) showed hypointensity on T1-weighted images and hyperintensity on T2-weighted images in most (5/6) lesions. Marked enhancement in the arterial phase was seen in 10 of 12 lesions on CT scans and in 6 of 6 lesions on MRI scans. All tumors were composed of varying proportions of smooth muscle, adipose tissue, and blood vessels, and showed positive immunohistochemical staining for HMB-45. All patients underwent partial hepatectomy and there was no evidence of recurrence after a median follow-up of 43 months.The radiological features of HAML vary according to its histological components. The definitive diagnosis of HAML is challenging and depends on the presence of HMB-45-positive myoid cells. Hepatic angiomyolipoma is treated effectively with surgery and the prognosis is good.

The problem of robust pole assignment (RPA) in high-order descriptor linear system is considered. By using the result of eigenstructure assignment via proportional plus derivative state feedback and the perturbation theory of generalised pole problem proposed by Stewart, the RPA problem in high-order descriptor linear system is converted into a minimisation problem, and a simple algorithm is derived for solution to this RPA problem. An example of third-order is worked out with multiple solutions, both the indices and the numerical robustness test demonstrate the effect of the proposed approach.

In terms of the original system matrices, a new criterion is given for the I-controllablisability of descriptor linear systems. The range of the dynamical orders that the resultant closed-loop system can achieve is also characterised. A general parameterisation of all the I-controllablising controllers that make the resultant closed-loop system have the desired dynamical order is presented. The design is based on orthogonal matrix transformations that can be implemented in a numerically stable way.

This paper is concerned with the problem of robust non-fragile fault-tolerant H ∞ control for a type of uncertain linear systems with state-delay. We design a fault-tolerant state feedback controller with parameter perturbation such that the fault closed-loop system is asymptotically stable and satisfies the H ∞ performance index. Based on Lyapunov function method the sufficient condition of the problem is presented as an LMI and the state feedback gain can be obtained in virtue of the solution to the LMI in practical application. The controller designed by this method can ensure the robustness and H ∞ property. Finally, a numerical example illustrates the effectiveness of the approach.

With the help of the concept of Kronecker map, an explicit solution for the matrix equation XF − AX = C is established. This solution is neatly expressed by a symmetric operator matrix, a controllability matrix and an observability matrix. In addition, the matrix equation XF-AX¯=C is also studied. An explicit solution for this equation is also proposed by means of the real representation of a complex matrix. This solution is neatly expressed by a symmetric operator matrix, two controllability matrices and two observability matrices.

This paper considers the problem of observer design in high-order descriptor linear systems. Parametric expressions for the left eigenvectors associated with the finite eigenvalues of the observer and simple and complete parametric solutions for the observer gain matrices are obtained on the basis of the parametric solution of the generalized high-order Sylvester matrix equation. This approach does not impose any restriction on the observer eigenvalues. An illustrative example shows the effect of the proposed approaches.

Eigenstructure assignment (ESA) in high-order linear systems via output feedback is considered. Parametric expressions for the left and right closed-loop eigenvectors matrices associated with the finite closed-loop eigenvalues are obtained on the basis of the parametric solutions of the generalized high-order Sylvester matrix equations. Furthermore, two simple and complete parametric solutions to the feedback gain matrices are given. Those approaches do not impose any restriction on the closed-loop eigenvalues.

To investigate outcomes after transanal endoscopic microsurgery (TEM) for early rectal cancer, identify risk factors associated with recurrence, and explore the indication of TEM for rectal cancer.Sixty patients with rectal cancer undergoing TEM between June 2006 and June 2009 in the Provincial Qianfoshan Hospital of Shandong University were included in this study and data were retrospectively analyzed.There were 12 patients with pTis rectal cancer, 38 with pT1 and 10 with pT2. All the lesions were excised en bloc by full-thickness TEM. No positive resection margins were reported. The operative time was(65.0 ± 36.5) min. Estimated blood loss was (10.5 ± 5.8) ml and hospital stay was(4.5 ± 2.7) d. No perioperative mortality and complications occurred. The median follow-up was 28.5(range, 12-48) months. No recurrence developed in pTis lesions. There was significant difference in local recurrence rate between pT1 and pT2(2.6% vs. 40.0%, P0.05). The recurrence rate in lesions larger than 3 cm in diameter(19.0%, 4/21) was significantly higher than that in lesions smaller than 3 cm in diameter (2.6%, 1/39) (P0.05). Multivariate analysis showed that depth of tumour invasion(T stage) and tumour size were independently associated with recurrence after TEM.Local excision by TEM is oncologically safe and effective for pTis and pT1 rectal cancers and early lesions smaller than 3 cm in diameter.

This paper considers pole assignment of large-scale systems via decentralized state feedback control. Based on the parametric eigenstructure assignment method, we propose two simple algorithms which assignment all poles of the isolated subsystems at predetermined location and let the poles of closed-loop systems close to that of the isolated subsystems by choose the parametric appropriately. The numerical illustration shows the effectiveness of the proposed methods

This paper considers model following control problem in high-order descriptor linear systems. The problem is converted into two high-order Sylvester matrix equations and stabilization of the high-order descriptor linear system. According to the solution of high-order eigenstructure assignment, parametric solutions to the stabilization problem are presented. Further by combining the two high-order Sylvester matrix equations into a generalized one, the parametric expressions for the feedback gain matrices are obtained. An illustrative example is given to show the effectiveness of the method.

This paper considers eigenstructure assignment (ESA) in high-order descriptor linear systems via output feedback. Parametric expressions for the closed-loop eigenvectors associated with the finite closed-loop eigenvalues, simple and complete parametric solution for the feedback gain matrices are obtained on the basis of the parametric solution of the generalized high-order Sylvester matrix equation. This approach does not impose any restriction on the closed-loop eigenvalues. An illustrative example shows the effect of the proposed approach.

This paper considers problem of observer design in high-order descriptor linear systems. Parametric expressions for the left eigenvectors associated with the finite eigenvalues of the observer and a simple and complete parametric solutions for the observer gain matrix are obtained on the basis of the parametric solution of the generalized high-order Sylvester matrix equation. This approach does not impose any restriction on the observer eigenvalues. An illustrative example shows the effect of the proposed approaches.

This paper considers eigenstructure assignment in high-order descriptor linear systems via proportional plus derivative state feedback. It is shown that the problem is closely related with a type of so-called high-order Sylvester matrix equations. Through establishing two general parametric solutions to this type of matrix equations, two complete parametric methods for the proposed eigenstructure assignment problem are presented. Both methods give simple complete parametric expressions for the feedback gains and the closed-loop eigenvector matrices. The first one mainly depends on a series of singular value decompositions, and is thus numerically simple and reliable; the second one utilizes the right factorization of the system, and allows the closed-loop eigenvalues to be set undetermined and sought via certain optimization procedures. An example shows the effect of the proposed approaches