104 research outputs found
MTHFD2 Overexpression Predicts Poor Prognosis in Renal Cell Carcinoma and is Associated with Cell Proliferation and Vimentin-Modulated Migration and Invasion
Background/Aims: To investigate the role of methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) in the clinical prognosis and cell biology of renal cell carcinoma (RCC). Methods: A total of 137 RCC tissues were evaluated by immunohistochemistry. The relationship between MTHFD2 overexpression and clinical parameters and vimentin expression was assessed. Kaplan-Meier curves and the log-rank test were applied for survival analysis according to MTHFD2 and vimentin expression in RCC tissues. The expression of MTHFD2 mRNA and protein was examined by quantitative reverse transcription PCR and western blotting, respectively. To determine further the biological activity of MTHFD2 in RCC, 786-O cells were transfected with short hairpin RNA specifically targeting MTHFD2 (shMTHFD2) with or without tumor necrosis factor (TNF)-α stimulation. Cell proliferation, cell migration and invasion and drug sensitivity were subsequently assessed using Cell Counting Kit-8, wound healing, and Transwell assays. Results: Immunohistochemical analysis demonstrated that both MTHFD2 and vimentin overexpression was positively associated with clinical staging, pathological grade, and poor overall survival (all P < 0.05). MTHFD2 expression was closely correlated with vimentin overexpression in RCC (r = 0.402, P < 0.001). After knocking down MTHFD2 expression in 786-O cells, decreased cell proliferation, migration, and invasion were observed and accompanied by the reduced expression of vimentin. The effects of MTHFD2 down-regulation could be partially restrained by TNF-α treatment. Vimentin expression and cell migration and invasion, but not cell proliferation, were reversed by TNF-α stimulation. Furthermore, treatment of 786-O cells with shMTHFD2 increased their sensitivity to chemotherapy drugs. Conclusion: The current results demonstrated that MTHFD2 was overexpressed in RCC and associated with poor clinical characteristics, vimentin expression, and cellular features connected to malignant disease, thus, implicating MTHFD2 as a potential target for RCC therapy
Research on the relationship between transmission efficiency and input torque of manual transmission
Based on the manual transmission of a micro car, this paper would present the analysis of the factors affecting the transmission efficiency (TE) and the calculation formula of TE. Accordingly, the calculation model of Matlab/Simulink TE would be built to figure out how TE varies with input torque. Meanwhile, a set of manual transmission test bench would be designed and used to verify the theoretical simulation results. It adopts a common DC bus energy feedback closed system which can feedback the power generated by the load motor to the grid through the DC bus so as to save the electricity and produce less pollution. Therefore, while the test bench can reflect the variation trend of TE about the manual transmission truly, it is comparatively reliable. Apart from being energy-saving, its unique versatility could definitely predict its exceptional potential. The data of TE obtained from the test bench are compared with the simulation result. It showed that the TE of bench test and simulation result are similar, though companied by less than 2% error difference which is within the allowable range. Most importantly, the bench test results proved the validity of the theoretical analysis statistically, which is of great necessity and significance to the research of TE
An Efficient Reanalysis Method for Topological Optimization of Vibrating Continuum Structures for Simple and Multiple Eigenfrequencies
This paper shows how the reanalysis method can be utilized for speeding up the optimized process in topology optimization related to vibrating structures for simple and multiple eigenfrequencies. The block combined approximation with shifting (BCAS) method is used for reducing the computational effort included in repeated solution of eigenvalue problem, which will dominate a lot of the CPU time, especially for large problems. By utilizing Level 3 Basic Linear Algebra Subprograms (BLAS), the computation efficiency of the BCAS method is improved. For achieving an accurate optimal result, two indicators are presented to control the approximate reanalysis procedure. The effectiveness of the proposed method is demonstrated by three numerical examples
Knowledge and Cross-Pair Pattern Guided Semantic Matching for Question Answering
Semantic matching is a basic problem in natural language processing, but it is far from solved because of the differences between the pairs for matching. In question answering (QA), answer selection (AS) is a popular semantic matching task, usually reformulated as a paraphrase identification (PI) problem. However, QA is different from PI because the question and the answer are not synonymous sentences and not strictly comparable. In this work, a novel knowledge and cross-pair pattern guided semantic matching system (KCG) is proposed, which considers both knowledge and pattern conditions for QA. We apply explicit cross-pair matching based on Graph Convolutional Network (GCN) to help KCG recognize general domain-independent Q-to-A patterns better. And with the incorporation of domain-specific information from knowledge bases (KB), KCG is able to capture and explore various relations within Q-A pairs. Experiments show that KCG is robust against the diversity of Q-A pairs and outperforms the state-of-the-art systems on different answer selection tasks
An Efficient Reanalysis Method for Topological Optimization of Vibrating Continuum Structures for Simple and Multiple Eigenfrequencies
Hydrogen stable isotope of the soil water during the growing season in the temperate steppe in Inner Mongolia, China_FEB26
Hydrogen stable isotope of the soil water during the growing season in the temperate steppe in Inner Mongolia, Chin
Experimental Investigation of Cracking and Impact Resistance of Polymer- and Fiber-Enhanced Concrete for Ultra-Thin Whitetopping
In order to investigate the effectiveness of polymer modification and fiber reinforcement on the cracking and impact resistance of concrete materials prepared for ultra-thin whitetopping (UTW), carboxyl butyl benzene latex and polyformaldehyde fibers were added to the conventional cement concrete mix. In addition, test methods that used an asphalt mixture performance tester (AMPT) and mechanical rammer were developed to evaluate concrete cracking and impact resistance, respectively. Results from the AMPT test revealed that the cracking resistance can be enhanced with polymer and fiber, especially the initial tensile load peak, which can be improved by more than 40% when fiber and polymer compound modification is applied. Meanwhile, the impact loading test revealed that the inclusion of both fiber and polymer results in a two-fold increase in the number of impacts before visible cracking occurs, and the number of blows to failure increased by 21.4%. Moreover, microstructures were investigated by scanning electron microscopy (SEM) to confirm the reinforcing mechanism of both polymer modification and fiber reinforcement
Modified Primary Anastomosis Using an Intestinal Internal Drainage Tube for Crohn’s Disease: A Pilot Study
Purpose: Surgical treatment is an important part of the management of Crohn’s disease (CD). However, the current recommended staged procedures require two operations, with long hospital stays and high costs, while traditional primary anastomosis has a high risk of complications. Therefore, the aim of this study was to compare the clinical efficacy and safety of modified primary anastomosis using intestinal internal drainage tubes for CD. Methods: In this study, emergency and nonemergency CD patients were included separately. Then, the patients were divided into three subgroups: patients with intestinal internal drainage tubes (modified primary anastomosis), staged procedures, and traditional primary anastomosis. The main outcomes were the number of hospitalizations, length and cost of the first hospital stay, length and cost of total hospital stays, and complications. Results: The outcomes of the three subgroups of emergency CD patients were not significantly different. For nonemergency CD patients, patients with intestinal internal drainage tubes had shorter total hospital stays and fewer hospitalizations compared with the staged procedures subgroup, while no significant differences in any outcomes were observed between the modified and traditional primary anastomosis subgroups. Conclusions: For emergency CD patients, no significant advantage in terms of the main outcomes was observed for modified primary anastomosis. For nonemergency CD patients, modified primary anastomosis reduced the length of total hospital stays and hospitalizations compared with staged procedures. The placement of intestinal internal drainage tubes allows some patients who cannot undergo primary anastomosis to undergo it, which is a modification of traditional primary anastomosis
Influence of Complex Service Factors on Ravelling Resistance Performance for Porous Asphalt Pavements
The study aims to analyze the influence of complex service factors on ravelling resistance performance for large-void asphalt pavements by carrying out tests on environmental and vehicle factors, conducting ultraviolet aging, freeze–thaw cycles, as well as vehicle speed simulated tests with the Rotating Surface Abrasion Test, vehicle tests, and traffic volume tests, and by making a correlation analysis between the Cantabro Abrasion test and Rotating Surface Abrasion Test. The result shows that environmental factors significantly affect the ravelling resistance performance of drainage asphalt pavements. With the increase in the times of UV aging and freeze–thaw cycles, the ravelling loss rate of asphalt specimens shows a tendency to increase, and the combined test of UV aging and freeze–thaw cycles aggravated the ravelling damage of asphalt specimens. Meanwhile, vehicle factors have a significant attenuation effect on the ravelling resistance performance of drainage asphalt pavements. With the increase in the speed, pressure, and times of the Rotating Surface Abrasion, the ravelling loss rate of asphalt specimens shows a steady tendency to increase. Furthermore, there exists a good correlation between the Rotating Surface Abrasion speed, pressure, times, and the ravelling loss rate. Finally, the two test results of the Cantabro Abrasion test and Rotating Surface Abrasion test are consistent in their changes during single/composite factor analysis, confirming the feasibility of using the Rotating Surface Abrasion test index to characterize the change in the ravelling resistance performance of drainage asphalt pavements
Rheological, mechanical, and abrasion characteristics of polymer-modified cement mortar and concrete
The settlement of fresh concrete or improper operation during construction usually makes the water to cement (w/c) ratio of the cement mortar on the concrete pavement surface higher than designed, which may influence the abrasion resistance of concrete pavement. This study firstly tried to establish relationships between abrasion of hardened cement mortar and rheological characteristics of fresh cement mortar in the laboratory. Secondly, a polymer-modified cement mortar was developed with carboxyl styrene butadiene rubber latex added to the cement mortar. Its rheological properties in mixing, mechanical properties, and abrasion were investigated. It is found that the polymer-modified cement mortar has a much better abrasion resistance and flexural strength while lower compressive strength than cement mortar. A stronger correlation was observed between flexural strength rather than compressive strength and abrasion resistance of cement mortar. The proposed polymer-modified concrete also exhibited good abrasion resistance.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
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