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Jane harmonic detection technology is an important content of power system harmonic governance, the paper proposes an improved ITD method combined with singular value difference spectrum of fast high precision detection. By improving the ITD method it can directly according to measured data with feature information contain system parameter identification. First, using singular value different spectrum system order, and then using ITD improved directly on the noise signal accurately detect the actual frequency of each harmonic, using the Least square method (further Squares, LS) on the amplitude of harmonic component between accurate detection. Improve ITD method with SSI method of covariance matrix (Toeplitz) as the input data, and overcoming the data processing method is not accurate, the error of the parameter identification precision is improved. Compared with the method of SSI, improved ITD method accuracy does not decrease, at the same time shortens the calculation time. Simulation results show that the method calculating speed, high precision, strong ability to resist noise, verify the feasibility and effectiveness of the proposed method.

Preoperative mechanical bowel preparation (MBP) has been established as a standard procedure for elective colorectal surgery in most surgical centers since 1950s. However, the routine use of MBP for elective colorectal surgery is still in debate, as the researches on the evaluation of MBP have been carried out in recent 20 years. By searching and analyzing the existing evidence, we conclude that MBP should be routinely abandoned for elective open colorectal surgery, but should be routinely used for elective laparoscopic rectal surgery, and it still awaits large-scale RCTs for further evaluation of MBP for elective laparoscopic colonic surgery.

To explore the mechanisms of MDSC trafficking and accumulation during tumor progression. In this study, we report significant CD40 upregulation in tumor-infiltrating MDSC when compared with splenic MDSC. Microarray analyses comparing CD40(high) and CD40l(ow) MDSC revealed 1872 differentially expressed genes, including CD83, CXCR5, BTLA, CXCL9, TLR1, FLT3, NOD2 and CXCL10. In vivo experiments comparing wild-type (WT) and CD40 knockout (KO) mice demonstrated that CD40 critically regulates CXCR5 expression. Consistently, the transwell analysis confirmed the essential role of CXCR5-CXCL13 crosstalk in the migration of CD40+ MDSC toward gastric cancer. Furthermore, more MDSC accumulated in the gastric cancers of WT mice when compared with KO mice, and the WT tumors mostly contained CD40+ cells. Functionally, tumors grew faster in WT than KO mice. In conclusion, we demonstrate that CD40 expression upregulates the chemokine receptor CXCR5 and promotes MDSC migration toward and accumulation within cancer. Therefore, this study provides preliminary evidence that CD40 may stimulate tumor growth by enabling immune evasion via MDSC recruitment and inhibition of T cell expansion.

A practical approach to simulate hydrodynamic performance of ducted propellers attached in an underwater vehicle under the influence of flow field of the vehicle is proposed, hydrodynamic characteristics of the propeller when the vehicle in a dynamic yawing motion is studied numerically. In the research, 3D geometric models of the duct, propeller and underwater vehicle are first constructed according to their geometrical features. Computational fluid dynamics (CFD) technique based on the finite volume method and multi-sliding mesh technique are applied to solve the Navier-Stokes equations which govern the fluid motions around the duct, propeller and underwater vehicle when the vehicle are in a yawing motion. These equations are solved numerically with the CFD code FLUENT. With the proposed numerical simulation approaches, the hydrodynamic phenomenon of thrusts generated from the ducted propellers in the vehicle system under the flow field influence of the vehicle’s yawing motion are analyzed. Results of our numerical simulation indicate that the influence of flow field caused by the underwater vehicle on the thrusts of the ducted propellers is not negligible; when studying the thrust characteristics of a ducted propeller in an underwater vehicle system, the thrust nature of the propeller can only be evaluated objectively on the condition that the vehicle and the ducted propeller are combined together into an integrated system, and the numerical simulation are conducted in such an integrated system.Copyright © 2015 by ASME

An alternative type of controllable underwater towed system is proposed. The towed vehicle in the system is composed of an adjustable depressing wing and a rectangular wing-shaped main body. Laboratory experimental observations on the behavior of this kind of towed system are reported and the experimental techniques to detect the hydrodynamic performances of the system are described. The results of the study indicate that with such a design the objective of rapid trajectory manipulation and relative stable attitude towing for the towed vehicle can be achieved; the experimental monitoring approaches provide an effective and reliable way to detect the hydrodynamic behavior of a towed system model tested in a ship model towing tank which would be quite useful in understanding the hydrodynamic and control behavior of the system.

The laparoscopic approach is rapidly becoming the preferred method of treatment for patients with early gastric cancer due to advantages of minimally invasive surgery. As laparoscopic experience has accumulated, laparoscopy-assisted distal gastrectomy (LADG) with D2 lymphadenectomy has become a valuable alternative for the treatment of patients with advanced gastric cancer. However, laparoscopic gastric surgery is demanding from a technical point of view, especially when a D2 lymphadenectomy is performed. Surgeons seeking to undertake LADG are concerned about unpredictable intraoperative bleeding that may occur during LADG. Comprehensive knowledge of the perigastric vascular anatomy is essential for LADG with D2 lymphadenectomy.

A hydrodynamic model of a two-part underwater manoeuvrable towed system is proposed in which a depressor is equipped with active horizontal and vertical control surfaces, and a towed vehicle is attached to the lower end of a primary cable. In such a system the towed vehicle can be manoeuvred in both vertical and horizontal planes when it is towed at a certain velocity and the coupling effect of excitations at the upper end of the primary cable and disturbances of control manipulations to the towed vehicle can be reduced. In the model the hydrodynamic behavior of an underwater vehicle is described by the six-degrees-of-freedom equations of motion for submarine simulations. The added masses of an underwater vehicle are obtained from the three-dimensional potential theory. The control surface forces of the vehicle are determined by the wing theory. The results indicate that with relative simple control measures a two-part underwater manoeuvrable towed system enables the towed vehicle to travel in a wide range with a stable attitude. The method in this model gives an effective numerical approach for determining hydrodynamic characteristics of an underwater vehicle especially when little or no experimental data are available or when costs prohibit doing experiments for determining these data.

An experimental set-up is developed and proved to be effective for laboratory study of an underwater towed system. The experimental technique gives a practical method for monitoring the kinematic and dynamic performance of an underwater towed system in a ship towing tank. Both the theoretical and experimental results in the investigation indicate that the hydrodynamic response of a towed vehicle to the wave induced motion of a towing ship can be significantly reduced by applying a two-part tow method. A comparison of the numerical and experimental results in the investigation demonstrates that the numerical simulation results are close to the experimental data, overall agreement between experimental and theoretical results is satisfactory. The results qualitatively verify the mathematical model of a two-part underwater towed system proposed by Wu and Chwang [Wu, J., Chwang, A.T., 2000. A hydrodynamic model of a two-part underwater towed system. Ocean Engineering 27 (5), 455–472].

A three-dimensional model of a two-part underwater towed system is studied. In the model, the governing equations of cables are established based on the Ablow and Schechter method. The boundary conditions for the two-part underwater towed system are derived. The six-degrees-of-freedom equations of motion for submarine simulations are adopted to predict the hydrodynamic performance of a towed vehicle. The established governing equations for the system are then solved using a central finite difference method. In this paper several algorithms are used to solve this special form of finite difference equations. The results in this paper indicate that the two-part underwater towed system improves the dynamic behavior of the towed vehicle and is an easy way to decouple the towing ship motion from the towed vehicle. Because the model uses an implicit time integration, it is stable for large time steps and is an effective algorithm for simulation of a large-scale underwater towed system.

This meta-analysis aimed to evaluate the short-term and pathological outcomes of laparoscopic surgery (LS) versus open surgery (OS) following neoadjuvant chemoradiotherapy (NCRT) for rectal cancer. PubMed, Embase, Web of Science, Cochrane Library, and Chinese Biomedicine Literature databases were searched for eligible studies published up to July 2013. The rates of postoperative complication, positive circumferential resection margin (CRM), and the number of lymph nodes harvested were evaluated. Three randomized controlled trials (RCTs) and five non-RCTs enrolling 953 patients were included. Compared to OS, LS had similar rate of postoperative complication [odds ratio (OR) 0.86; 95 % confidence interval (CI), 0.60 to 1.22], comparable rate of positive CRM (OR 0.41; 95 % CI, 0.16 to 1.02), and smaller number of lymph nodes (weighted mean difference −0.8; 95 % CI, −1.1 to −0.5). LS also had significantly less blood loss, faster bowel movement recovery, and shorter postoperative hospitalization than those of OS. LS is associated with favorable short-term benefits, similar postoperative complication rate, and comparable pathological outcomes for rectal cancer after NCRT compared to OS despite a slight difference in the number of lymph nodes. Additional high-quality studies are needed to validate long-term outcomes of LS following NCRT.

Contemporary urban living environment design and construction process are facing lots of ecological issues. It needs us to find a new perspective and efficient design approach which can become the bridge or link between special form and optimized function structure, natural and human resources protection, traffic and physical environment improvement, land-use saving and energy sustainability, landscape environment and behavior system design, etc. Based on Urban Design subject, Ecological Urban Design regards special environment system as research object, uses Ecology principles for reference, harmonizes relationship of natural and built environment and urban inhabitant, and becomes an important method and theory to adjust urban special environment ecology. For promoting Ecology Urban Design theory developing, it is necessary to create a research and practice platform for Urban Design and Ecology. Meanwhile, we need not only absorb foreign experiences, but also recognize our country objective condition and demand, explore Chinese Ecological Urban Design theory and practice. It has an important meaning to build up our country living ecological environment and develop local Urban Design theories.

In practice, such a problem is often encountered that the proportion of target to background in image segmentation is very small. For this, a thresholding method used for the image segmentation of infrared small target is proposed in this paper, which is based on the area difference between background and target and intra-cluster variance. This method points out the existing methods of image threshold segmentation can not effectively extract infrared small targets, and offers the thresholding formula of the area difference between background and target and intra-cluster variance based on 2-D histogram of vertical and more effective oblique. It puts forward the niche chaotic mutation particle swarm optimization algorithm based on 2-D histogram of vertical and oblique. Finally the result and running time of this paper are given out in the result and analysis of experimental, which is compared with the NCPSO of 2-D Otsu, maximum and Fisher. The results show that the method in this paper can accurately extract infrared small targets, and has short running time and strong anti-noise performance.

Ethnopharmacological relevance Curcuma zedoaria (Berg.) Rosc., a traditional Chinese herb, was used widely but absolutely prohibited for the pregnant in clinic. Based on that there is abundant angiogenesis in endometrium and placenta during gestation period, we hypothesized that some components from it could inhibit angiogenesis and then damaged the supply of oxygen and nutrition to the embryo, which finally led to gestation failure. Aim of the study This study was set to demonstrate whether essential oil, major components of Curcuma zedoaria had anti-angiogenic effect. Materials and methods Essential oil of Curcuma zedoaria (EO-CZ) was abstracted by steam distillation extraction. Cell proliferation assay and two angiogenic models, rat aortic ring assay and chick embryo chorioallantoic membrane assay were presented. Furthermore, melanoma growth and experimental lung metastasis assay in mice were performed to evaluate its anti-angiogenesis effect in vivo. Immunohistochemical analysis and enzyme-linked immunosorbent assay (ELISA) were used to respectively detect the expression of CD34 and matrix metalloproteinases (MMPs). Results EO-CZ exhibited anti-proliferative effect on B16BL6 and SMMC-7721 cells, the IC50, respectively was 41.8 μg/ml and 30.7 μg/ml, and on HUVEC (Human Umbilical Vein Endothelial Cells) cells with IC50 of far more than 120 μg/ml. Both 20 μg/ml and 40 μg/ml EO-CZ indicated significant suppression on sprouting vessels of aortic ring and formation of microvessels in chick embryo chorioallantoic membrane in vitro. Moreover, solid melanoma grown in left oxter of mice was obviously inhibited after oral intake of 100 and 200 mg/kg of EO-CZ a day for 28 days, and CD34 expression indicating angiogenesis in melanoma reduced significantly compared with control; melanoma metastatic nodules in lung were detected to be inhibited, as well as MMP-2 and MMP-9 expression in serum. Conclusions Essential oil, a fat-soluble fraction of Curcuma zedoaria, presented anti-angiogenic activity in vitro and in vivo, resulting in suppressing melanoma growth and lung metastasis. And this was associated with down-regulating MMPs.

The marine power plant traditional design method was popular introduced when the computer design and application had not yet appeared. Based on the analysis of the problems of the traditional design method of the marine power plant, the issue that applying digital design method to the design process of the marine power plant was studied in this paper. The digital design scheme for the marine power plant was proposed, and the key problems was studied. The research in the paper could help to improve the design of the marine power plant.

From the aspect of methods, technique and data, bringing forward that the spatial organization of FNLCR has spatialized and digitalized characteristics. In the research, the main requirement of data includes the data of 2D vector graphics, RS image, the data of digital elevation models, the data of various statistics, and the data of 3D urban graphics and texture, etc.. Bringing forward the basic logic of the spatial organization research of FNLCR, and discuss the division of the factors.

In terms of methodology, technology and data demand, the study on spatial organization of functional network in low-carbon region (FNLCR) is identified by the spatialized and digitalized characteristics. Therefore, digital city technology (DCT) becomes important in the study of spatial organization of FNLCR. The research components and ideas are provided, and the research approach named digital low-carbon region (DLCR) with broad connections with DCT is proposed. An initiative framework of spatial organization of FNLCR is presented based on the platform of DCT, and it will help to establish a complete routine of digital low-carbon planning (DLCP) on regional scale.

Danshensu, the major water-soluble component of Radix Salviae Miltiorrhizae (Danshen), is the basic chemical structure of various salvianolic acids. This study was to evaluate the anti-tumor activity of danshensu in a series of in vitro and in vivo models. The effect of danshensu on B16F10 melanoma cell and HUVEC proliferation were assessed by MTS assay, and cell invasion and migration were investigated by transwell chamber assay. The effect of danshensu on angiogenesis was evaluated by HUVEC migration assay, tube formation assay and chick chorioallantoic membrane assay. The expression of MMP-2, -9 and VEGF in B16F10 melanoma cell were detected by western blotting after danshensu treatment. The role of danshensu in tumor metastasis in vivo was evaluated by spontaneous and experimental B16F10 melanoma metastasis model. Although danshensu had no inhibitory effect on B16F10 melanoma cell and HUVEC proliferation, it significantly inhibited B16F10 melanoma cell invasion (at 0.05, 0.5, 5 microM) and migration (at 0.5, 5 microM). It also dramatically suppressed VEGF-induced endothelial migration (at 0.5, 5 microM), tube formation in vitro (at 4, 20 microM) and new vessel formation in CAM in vivo (100 microg/egg). Danshensu (at 5, 50 microM) significantly down-regulates protein expression of MMP-2, -9 and VEGF in B16F10 melanoma cell. In animal model, danshensu (20, 40 mg/kg) also possessed inhibitory effect on lung metastasis in spontaneous (46-day treatment) and experimental (23-day treatment) B16F10 melanoma metastasis model. All these results suggest that danshensu has anti-tumor activity by affecting on tumor angiogenesis and tumor invasion.

Acidic mucopolysaccharide from Holothuria Leucospilota (HS) may affect some steps in metastasis cascade. In vitro, HS inhibited the growth of B16F10 cells and proliferation of VEGF-induced HUVEC dose-dependently compared to the control, VEGF-induced capillary-like tube networks and the numbers of migratory and invasive cells were significantly inhibited by HS in a dose-dependent manner under the cytotoxic doses. Additionally, VEGF-induced vessel sprouting of rat aortic ring was also inhibited by HS. It also has been demonstrated that the invasive ability of B16F10 melanoma cells through the Matrigel-embedded Boyden chamber was suppressed by 0.5 muM HS. The protein level secreted by B16F10 cells of MMP-2,-9 and VEGF were decreased by HS treatment. In vivo, a tumor growth inhibition study was carried out using mice bearing B16F10 cells model of metastasis, no matter experimental or spontaneous, showed that HS at 5.2, 11.6 and 26 mg/kg (weight of mice) could markedly decreased the metastatic tumors in mouse lung in a dose-dependent manner. In CAM assay and Matrigel plug assay in vivo, HS (50 microg/egg and 100 microg/egg) inhibited new blood vessel formation on the growing chick chorioallantoic membrane, and HS (5.2 and 26 mg/kg body weight) reduced the vessel density in Matrigel plugs implanted in mice. Taken together, these results demonstrate that HS has antimetastasic properties possibly via its antiangiogenesis induced by downregulation of VEGF and suppression of invasive ability of cancer cells mediated by downregulation of MMP-2, -9 and their activities.

A new concept of control technique to perform operation of trajectory maneuvering to a controllable underwater towed vehicle moving in a designated path with a required attitude is presented. A trajectory and attitude control technique for the towed vehicle is proposed in order to accomplish the vehicle’s trajectory and attitude manipulations. This technique is based on a fuzzy algorithm. The towed vehicle in the research consists of a cylindrical main body equipped with several active horizontal and vertical control surfaces. Numerical simulation on the hydrodynamic and control behavior of the towed vehicle under this control manipulation is conducted based on a fully 3-D hydrodynamic model of an underwater towed vehicle. In the model the governing equation of the towed cable is based on the Ablow and Schechter method. The six-degrees-of-freedom equations of motion for an underwater vehicle simulation proposed by Gertler and Hagen are adopted to estimate the hydrodynamic performance of the towed vehicle. In numerical simulation the deflections of vehicle’s control surfaces are governed by the proposed fuzzy controller to manipulate the vehicle traveling along a 3-D stipulated trajectory configuration and required attitude. The values of the deflections are taken as input parameters for the hydrodynamic model at every time step. The performance of the towed vehicle under different designated trajectory and attitude control manipulations can then be investigated with the hydrodynamic model.Copyright © 2006 by ASME

The hydrodynamic and control performances of a self-stable controllable underwater towed vehicle developed by South China University of Technology under different depth trajectory control operations are analyzed by means of a proposed hydrodynamic numerical model. The model is established based on LMBP algorithm of neural network theory. Training samples for the neural network model are provided from the experimental data of the vehicle prototype towing experiments conducted in a large-scale ship model towing tank under the manipulation of a depressing wing installed in the vehicle. After the LMBP model is established, a depth trajectory control system for the towed vehicle is designed in order to accomplish vehicle trajectory control. This system is mainly composed of tow parts: a neural network identifier based on genetic algorithm and a fuzzy neural network controller based on genetic algorithm simulated annealing. Hydrodynamic performances of the vehicle under various control operations can then be numerically simulated with the proposed LMBP model and the depth trajectory control system of the towed vehicle. In numerical simulation of trajectory control to the towed vehicle, deflection of the vehicle’s depressing wing is adjusted at every time step by the proposed control system to match the trajectory of the vehicle with a pre-designated one. The value of the deflection is taken as input parameter for the LMBP neural network model, trajectory and attitude behavior of the towed vehicle under the control manipulations can then be predicted by the LMBP model.Copyright © 2006 by ASME