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Background: Circular RNAs are a class of non-coding regulatory RNAs reported to be involved in cancer development and progression. Previous studies, including our own, have indicated that hsa_circ_0007444 was downregulated in ovarian cancer (OC) tissues. Herein, we demonstrated another mechanism of hsa_circ_0007444 in ovarian cancer.Methods: The expression of hsa_circ_0007444, miR-23a-3p, and DICER1 were determined by quantitative real-time PCR. Cell proliferation, invasion, migration, and apoptosis were examined by cell counting kit 8, transwell, and flow cytometry assays. The roles of hsa_circ_0007444 in tumor growth and metastasis were assessed in vivo using a nude mouse xenograft model. The bioinformatics tools were employed to predict the binding sites, which were then verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assays. DICER1 protein level was measured by western blot. Results: Hsa_circ_0007444 was downregulated in ovarian cancer cell lines compared with normal ovarian epithelial cell lines. Also, gain- and loss-of-function results indicated that hsa_circ_0007444 inhibited cell proliferation, invasion, migration, increased cell apoptosis of ovarian cancer cells in vitro, and impaired tumor growth and lung metastasis in vivo. Additionally, the results of the bioinformatics analysis, RIP, dual-luciferase reporter, and rescue assays confirmed that hsa_circ_0007444 could interact with AGO2 and sponge miR-23a-3p, thereby upregulating DICER1 expression, which was an important tumor suppressor in ovarian cancer.Conclusion: We found that overexpressed hsa_circ_0007444 could inhibit ovarian cancer progression through the hsa_circ_0007444/miR-23a-3p/DICER1 axis.

Background: Positive surgical margins are independent risk factor for biochemical recurrence, local recurrence, and distant metastasis after radical prostatectomy. However, limited predictive tools are available. This study aimed to develop and validate a preoperative nomogram for predicting positive surgical margins after laparoscopic radical prostatectomy (LRP). Methods: From January 2010 to March 2016, a total of 418 patients who underwent LRP without receiving neoadjuvant therapy at Peking University Third Hospital were retrospectively involved in this study. Clinical and pathological results of each patient were collected for further analysis. Univariable and multivariable logistic regression (backward stepwise method) were used for the nomogram development. The concordance index (CI), calibration curve analysis and decision curve analysis were used to evaluate the performance of our model. Results: Of 418 patients involved in this study, 142 patients (34.0%) had a positive surgical margin on final pathology. Based on the backward selection, four variables were included in the final multivariable regression model, including the percentage of positive cores in preoperative biopsy, clinical stage, free prostate specific antigen (fPSA)/total PSA (tPSA), and age. A nomogram was developed using these four variables. The concordance index (C-index) of the nomogram was 0.722 in the development cohort and 0.700 in the bootstrap validations. The bias-corrected calibration plot showed a limited departure from the ideal line with a mean absolute error of 2.0%. In decision curve analyses, the nomogram showed net benefits in the range from 0.2 to 0.7. Conclusion: A nomogram to predict positive surgical margins after LRP was developed and validated, which could help urologists plan surgical procedures. Key words: Prostate cancer; Positive surgical margins; Laparoscopic radical prostatectomy; Nomogram

The Gim tire model was adopted to set up the nonlinear dynamic model of tractorsemitrailer. Choosing the slip angle of tractor, the yaw velocity of tractor, the yaw velocity of semitrailer, and the angle between tractor and semitrailer as control variables, as well as considering the uncertain characteristic of the tire cornering stiffness, the optimal guaranteed cost control scheme was proposed. An optimal guaranteed cost controller of DYC for the tractor-semitrailer stability was developed based on model following technique. Based on the established nonlinear dynamic model, simulation in Matlab/Simulink software environment was described. The simulation results suggest that for the tractor-semitrailer with optimal guaranteed cost controller of DYC, the handling and stability performance on big slip angle is improved. The conclusion can be useful for the system design of tractor-semitrailer.

Hybrid tree harvester with a 60 kW diesel engine combined with a battery pile could be a “green” forest harvesting and transportation system. With the new design, the diesel engine maintains a constant engine speed, keeping fuel consumption low while charging the batteries that drive the forwarder. As an additional energy saving method, the electric motors work as generators to charge the battery pile when the vehicle moves downhill. The vehicle is equipped with six large wheels providing high clearance over uneven terrain while reducing ground pressure. Each wheel is driven via a hub gear by its own alternating current motor, and each of the three wheel pairs can be steered independently. The combination of the diesel engine and six electric motors provides plenty of power for heavy lifting and pulling. The main component parameters of the drive system are calculated and optimized with a set of dynamics and simulated with AVL Cruise software. The results provide practical insights for the fuel tree harvester and are helpful to reduce the structure and size of the tree harvester. Advantage Environment provides information about existing and future products designed to reduce environmental impacts.

In this study, we observed antiatheroscloresis ability of food-roune hyperlipidemia by total falconoid from Jumi in rats. We used hyperlipidemia model of rats established, intervened by total falconoid from Jumi. Rats were divided into normal control group, hyperlipidemia control group, higher dose group and lower dose group to observe the level of total cholesterol (TC), trilaurate glycerin (TG), high density lipoprotein (HDL), low density lipoprotein (LDL) and atherogenic index (AI), and take rat liver for regular pathological dyeing observation. The results shown that the total falconoid from Jumi could reduce the serum levels of TC, TG, LDL and AI significantly, and increase HDL/TC in compared with hyperlipidemia control groups. It had significantly curative to effect hepatic adipose infiltration in rats, especially in low doses of flavonoid. Total flavonoids from Jumi can regulate disturbance of lipid metabolism, hepatic adipose infiltration and arteriosclerosis.

Aiming at the interferometric inverse synthetic aperture radar (InISAR) imaging in the presence of squint, we investigate the influence of squint on the InISAR imaging. First, coupling of the squint additive phase and the target azimuth/altitude coordinates to be solved may make the solution more difficult. Second, the squint angle may lead to estimation error of the vertical coordinates and distortion of the ultimate image. Traditional InISAR imaging algorithms can not solve the above two problems effectively, so we propose a new method which combines the nonlinear least square (NLS) and coordinates transform (CT) to estimate the target coordinates, and a three-dimensional (3-D) image consistent with the real target is obtained accordingly. Simulations show that the proposed method is effective for the squint-mode InISAR imaging.

The laser induced damage in high-power laser system has received much attention in the area of laser engineering. Optical components with contaminants, which are installed in the final optical assembly (FOA), can be severely damaged under the action of extremely high laser energy. So the ultra-high cleanliness inside the high-energy laser system is required for both optical and mechanical components. Research shows that a large part of the metal particulate contaminants inside the device come from the mechanical components. The metal particulate contaminants are produced when mechanical structure surface is damaged under the irradiation of stray light. However the research about the cleanliness inside the device is mostly concentrated on the surfaces of optical components currently. The laser ablation of the mechanical components absorbing contaminants is studied little, so it is quite important to investigate the ablation mechanism of mechanical components under laser irradiation. Due to the presence of contaminants on the surfaces of mechanical components, laser ablation of monocrystalline iron absorbing contaminants is investigated by using molecular dynamics simulation. The ablation process of iron material under laser irradiation is presented. The influences of loading mode and energy density of laser as well as contamination on the surface are analyzed in the ablation process of monocrystalline iron. The results indicate that the surface atoms of monocrystalline iron show different motion states under the violent collision of contaminants atoms after laser loading. Ablated iron can be divided into ablation zone, melting zone and crystal zone according to the variation of the temperature and mass density of the atoms in each region of the ablated material. The atoms in each region show macroscopic characteristics of gaseous, liquid and solid atoms respectively. Iron is damaged more easily when laser energy is instantaneously loaded. Contaminants on the surface of iron can be removed, and iron cannot be damaged when laser energy density is below 0.0064 J/cm2. The result of the analysis shows that the presence of contaminants makes the ablation of iron easier. Different energy loading modes affect the heat transfer mode directly. Monocrystalline iron materials are more likely to be damaged in the mode of adiabatic laser ablation in the case of short laser pulse. Thermal effect can be thought as a dominant factor for the ablation in the case of long laser pulse. The research results of this paper are helpful for providing the theoretical basis for improving the cleanliness of high-power laser system.

Polar molecules dominated electrorheological fluids mainly comprising a mixture of dispersed phase of solid particles and/or dispersing liquid medium. The dispersed phase solid particles, on the surface, or the liquid dispersing medium contain polar molecules or polar groups, the dipole moment of which is 0.5-10 deb and the size is between 0.1 nm and 0.8 nm. Dispersed phase solid particles are spherical or nearly spherical, of which the size is 10-300 nm and dielectric constant is higher than 50. The conductance rate of the liquid dispersing medium is lower than 10 −8 S/m, and the dielectric constant is lower than 10. The PM-ER fluids possess the characteristics of high yield strength, high dynamic shear strength, low leakage current, the linear dependence of yield strength on electric field, and high yield strength at low electric field, etc. The yield strength improves to almost 100 times of that of ordinary ER fluids and reaches to more than 200 Kpa.

After a survey of modem enterprise model systems, a three-dimension global enterprise model framework (GEMF) for business reengineering (BR) is proposed in this paper. Aimed at the most important model tools in the model framework, a business process model based on Petri Net is then designed. Also a hybrid mode ling and model redesign method is discussed in this paper.

Today, nonlinear analysis is no longer new to finite element society, but the explicit finite element method could still be fresh. Since DYNA3D was developed, the explicit finite element method for nonlinear transient dynamics has found its successful applications in automobile safety simulations. Ford Motor Company is one of the pioneer industry companies that uses a great deal of CAE in product design and manufacturing. This helps Ford engineers make faster and better design, eliminates a large number of prototype vehicle tests and significantly reduces the costs. Presented in this report are selected examples of our applications in safety simulations and other CAE activities, all done by Ford in-house crash simulation code FCRASH.

The collision problem between tags in Radio Frequency Identification (RFID) system is one of the most important issues that affect the system performance. The multi-tag anti-collision algorithm in the RFID system can be divided into binary tree based algorithms and ALOHA based algorithms at present. The binary tree based algorithms use tag ID to judge collision and have been employed popularly as its high efficiency. However, one of the disadvantages in the binary tree algorithms is that large amount of data have to be transmitted in system. A modified binary tree anti-collision algorithm is proposed in this paper. Firstly, the algorithm dispersed tags randomly. Then, the algorithm took short random number as tag temporary ID to avoid direct transmission of tag ID. Compared to the existing binary tree algorithms, the results of experiments show that the proposed algorithm reduces the amount of data traffic greatly and improves the identification rate significantly.

A new dynamic frame slotted ALOHA algorithm used in Radio Frequency Identification (RFID) systems is presented in this paper. An effective tag-grouping method is proposed in the algorithm. Theoretical analysis shows that the tag-grouping method can disperse tags quickly and evenly. Based on tag grouping, a reader in RFID system can identify tags group by group. The simulation results show that the algorithm can maintain the efficiency near the theoretical maximum of the FSA algorithm, and the efficiency of the algorithm is higher than other typical DFSA algorithms.

This paper examines the feasibility of applying a micro hydro power generation system as one of the enabling technologies that previously submitted for a balanced distributed generation strategy through a modified Microgrid as part of the various regional energy programs underway in Africa. In addition, this paper also points to R&D advancements in various technologies focused on energy sustainability. Our evaluation suggests that micro hydro power generation systems integrated even at Microgrid powered levels have potential to provide an efficiency of service to rural communities. Since they will be able to provide voltage and frequency control, this development will serve as primary building blocks for future system expansion. Issues regarding the potential resources for hybrid distributed generation and reliability of power supply are addressed.

A new kind of oil-mist collection is design to reduce the harm of oil-mist produced by cold-former to people and environment. This paper stimulates the flow field of oil-mist cooling and separation device by using Fluent and obtains the speed vector by adopting the standard κ -ɛ turbulence model and supplying air from different speed. It is validated that the device is a perfect part of the oil-mist collection. (5 pages)

RPROP is a fast BP algorithm in which the weights are adjusted local adaptively and the parameters can be chosen easily. The RPROP algorithm was introduced for feature-level fusion recognitions in this paper and the technologies of BP algorithms in feature-level recognitions were discussed here. The data of 5 vehicles were measured in darkroom with 2 different kinds of sensors, infrared radiation (IR) sensor and radar. Using features extracted from the data, the comparative experiments between the learning-rate descent BP (LDBP), the variable learning-rate BP (VLBP), the adaptive momentum BP (AMOBP) and resilient BP (RPROP) algorithms were emulated when they were applied in feature-level fusion recognition. The ROROP gives the most steady and fastest results even that high accuracy is demanded. All the algorithms had given the equivalent recognition rates after convergence at the equivalent error level. The experiments have proved that RPROP is an efficient BP algorithm for feature-level fusion recognition.

Crashworthiness analysis, a type of large deformation transient dynamics, has been an important and active area of researches and engineering applications. Several shell elements have been implemented in the finite element software for crashworthiness analysis. Among them, the 4-node quadrilateral Belytschko-Tsay element, using lower order integration technique is most commonly employed, due to its efficiency, robustness and overall accuracy. However, the lower order integration brings in some uncertainty. This paper is to conduct an engineering evaluation on performance of various shell elements, including Belytschko-Tsay, Belytschko-Leviathan (QPH), Bathe-Dvorkin, discrete Kirchhoff triangular elements, available in the commercial explicit finite element software. The study uses several linear and nonlinear benchmark examples and high-speed impact examples, to investigate the performance of these elements. Results of engineering interest and efficiency of computation are reported. Also, the behavior of finite element convergence, observed from the results by a sequence of refined meshes is investigated.

An approach is proposed to monitor the rate of lump coal based on image processing. The video signal output from a camera is put into a computer image gathering card to get the lump coals original picture in the coalface. After pretreatment and edge enhancement, the computer recognizes the lump coal and calculates its size. Finally, we count the data, display and print the result. Using this method, we effectively improve the quality of raw coal on a comprehensive mechanized coalface.

Business reengineering (BR) is a new concept of organization and management, and its model is of great importance. First, through enhancing the SLANG language and a model for software process development, a Petri net based business process model is described for BR. A hybrid modeling method that combines top-down and bottom-up principles is then explored. Finally, the model and its modeling method are illustrated by an example.

Fully conjugated and rodlike poly[(1,7-dihydrobenzo[1,2-d:4,5-d′]diimidazole-2,6-diyl)-2-(2-sulfo)-p-phenylene] (sPBI) was synthesized and fabricated for monolayer light emitting diodes showing a threshold voltage of 4.5 V and an emission λmax of 530 nm. Intractable sPBI was derivatized for a fully conjugated water soluble rigid-rod polyelectrolyte sPBI-PS(Li+) which was doped with LiCF3SO3 or LiN(CF3SO2)2 for optical absorption, electrical conductivity, and luminescent emission. sPBI-PS(Li+) light emitting electrochemical cells doped with 0.41 and 1.01 wt % of LiN(CF3SO2)2 showed a threshold voltage of 2.8 V and a tenfold increase in electroluminescence intensity (at λmax=514 nm) which did not increase with its conductivity.