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This paper proposed a new ordering criterion which could be used by classifiers selection algorithm based on ordered aggregation. For calculating the competence of the classifier, it used a randomized reference classifier for modeling the classifier to get the probabilistic model of classifier competence. By combining with ordering criterion based on classifier competence of margin, the paper proposed a novel dynamic ensemble selection algorithm(CCM-DES) for improving the performance of the ensemble. CCM-DES first divided feature space into different regions, and then constructed optimal ensembles in every region. It used DES for classify the unlabeled sample at last. Experiments on UCI datasets show that the criterion based on margin classifiers competence is better than current ordering criterion. Furthermore, CCM-DES has the advantages of smaller ensembles, higher accuracy, shorter classifying time than current ensemble algorithm. [ABSTRACT FROM AUTHOR]

The result of classical classification algorithms in the case of imbalanced data sets is not satisfactory. In order to improve the classification performance under imbalanced data sets, especially the classification ability of the minority class, this paper presented a novel classification algorithm for imbalanced data sets based on combination of border synthetic minority oversampling technique (BSMOTE) and inverse under sampling. It used BSMOTE to increase the sample number of minority class, and then used a inverse under sampling method to inverse the cardinalities of the majority and minority class ratio through removing the samples of redundant and noise sample firstly. By sampling several times, it created a large number of distinct training sets. It used Bagging method to ensemble the classifiers trained on those data sets to improve the efficient use of the original data sets. Experimental results show that the proposed algorithm can not only improve classification performance in the minority class data, but also increase the overall classification accuracy rate effectively than several existing algorithms. [ABSTRACT FROM AUTHOR]

The tillering angle was an important plant type trait of rice, and the suitable tillering angle was the key factor to achieve the high yield of rice. The specific molecular marker S-TAC1 based on STARP (Semi-thermal asymmetric reverse PCR) technology was designed for the functional site of TAC1, which was the major efficiency gene controlling the tillering angle of rice, and the genotype identification of 56 sequenced conventional rice varieties and 164 hybrid rice varieties were conducted. S-TAC1 accurately identified the genotypes of 56 sequenced conventional varieties, including 36 compact homozygous genotypes tac1/tac1 and 20 incompact homozygous genotypes TAC1/TAC1, which indicated that the S-TAC1 typing results were accurate and reliable. Among 164 hybrid rice varieties, 62 were heterozygous genotypes TAC1/tac1 and 102 were incompact homozygous genotypes TAC1/TAC1. The functional markers developed in this study provided technical support for the cultivation of rice varieties with ideal plant type by molecular marker-assisted selection. [ABSTRACT FROM AUTHOR]

Aiming at the problem that the feature selection based on constraint score can be easily affected by the composition and cardinality of pairwise constraints, this paper presented a new method called dynamic ensemble selection based on bagging constraint score. The algorithm introduced bagging constraint score into dynamic ensemble selection, divided the sample space into different parts, and then used the multi-population genetic algorithm to select the optimal multi-classifiers ensemble for the accuracy of the local classification. The experimental results on UCI datasets illustrates that the BCS-DES is smaller affected by the composition and cardinality of the pairwise constraints than the current feature selection methods, and can get better results. [ABSTRACT FROM AUTHOR]

According to the fact that conventional color image filtering algorithms do not distinguish whether the pixels in the sliding window are noise pixels and thus leading to poor filtering results, this paper proposed a switching vector median filtering method based on fuzzy decision. Firstly, it used the switching conditions to determine whether the center pixel of a neighborhood was noisy. For the corrupted pixels in color image, it constructed a membership function for removal of noise pixels according to fuzzy mathematical theory, estimated all the pixels' memberships in the sliding window according to the proposed membership function. And then it removed some pixels with high membership in terms of the confidence interval. Finally, it employed VMF in the optimized sliding window. Compared with the existing method, the novel method could improve the filtering results by removing the suspected noise pixels in the sliding window. Experimental results show that the proposed method performs better performance of robustness and practicality. [ABSTRACT FROM AUTHOR]

Objective To explore the expressions of Sirt1, P53 and P-gp in gastric carcinoma and investigate their correlations with clinicopathological characteristics as well as survival and prognosis. Methods The expressions of Sirt1, P53 and P-gp were detected in 68 cases of gastric carcinoma tissues and normal tissues with immunohistochemical method. The relationship between the expressions and the 68 patients' survival time was analyzed by Kaplan Meier survival curve. Results Sirt1, P53 and P-gp expressions were significantly higher in gastric carcinoma tissues than in normal tissues (P<0.01). The high expression of Sirt1 was correlated with invasion depth, lymph node metastasis and clinical TNM stage. Moreover, deeper invasion, lymph node metastasis and higher clinical TNM stage were related to higher Sirt1 expression (P<0.05). A positive correlation was found between Sirt1 expression with P53 and P-gp in gastric carcinoma (P<0.001). The survival time was shorter in patients with positive Sirt1 expression than those with negative expression (P<0.001). Conclusion The expressions of Sirt1, P53 and P-gp are higher in gastric carcinoma than in normal tissues and are related to the pathological characteristics of gastric carcinoma. Therefore, Sirt1, P53 and P-gp expressions detected in combination can serve as indicators for judging survival duration and prognosis of gastric carcinoma patients. [ABSTRACT FROM AUTHOR]

Objective To establish a method of cultivation of dendritic cells(DC) from mouse bone marrow in vitro and identify their phenotype and function. Methods Under aseptic condition, bone marrow cells were extracted from the tibia and femur bones of BALB/c mice. Bone marrow cells were cultured with recombinant mouse granulocyte--macrophage colony--stimulating factor (rmGM-CSF ) in vitro. The expansion and morphological changes of DC were observed with light inverted microscope. Phenotype was identified with flow cytometry and biological function was studied with antigen phagocytosis test. Results A large number of immature and mature DC with typical dendritic morphological characteristics could be generated from murine bone marrow. Immature DC, which had high expression in CD11c and low expression in CD40, MHC-II and CD86, could phagocytize antigen. Mature DC, which could be induced from immature DC by lipopolysaccharides, had high expression in CD11c, CD40, CD86 and MHC-II molecules. Conclusion Immature and mature DC can be generated from mouse bone marrow cells through cytokine induction in vitro and be used for further study associated with DC. [ABSTRACT FROM AUTHOR]

Most of the existing pricing models for convertible bonds are based on the framework of rational investors, which ignore the impact of heterogeneous investors, resulting in valuation inaccuracy and being difficult to explain some abnormal phenomenon in the market such as convertible bonds underpricing or call late (early). Under the framework of behavioral finance, this paper uses the regret aversion to stand for the heterogeneous beliefs of investors, and a revised pricing model is constructed subsequently. Focusing on the call strategy, we analyze the impact of investors' heterogeneous beliefs on the convertible bonds. Results of theoretical model and numerical simulation both point out the regret aversion of convertible bonds issuers could explain call strategy of convertible bonds late(early) properly. [ABSTRACT FROM AUTHOR]

AIM: To investigate the effect of conditioned medium from hypoxia/reoxygenation (H/R)-treated rat cardiac fibroblasts (CFs) on gap junction between cardiomyocytes and determine whether its mechanism is related to matrix metalloproteinase 2 (MMP2) activity. METHODS: (1) H9c2 cells were randomly divided into five groups: control group, normal group, ARP-100 group, H/R group, and H/R+ARP-100 group. Scrape loading/dye transfer assay was used to assess the gap junction function. Western blot was used to detect the expression and phosphorylation levels of Cx43. Gelatin zymography assay was performed to measure MMP2 activity. (2) SD rats were randomly divided into control group, ARP-100 group, ischemia-reperfusion (I/R) group, and I/R+ARP-100 group, with 8 rats in each group. Micro-electrode array technology was used to record the type and duration of arrhythmia. Immunohistochemistry experiment was performed to assess expression levels and distribution of Cx43 in myocardial tissues. RESULTS: Compared with the control group, the H/R group showed decreased protein expression of Cx43 (P<0. 01), narrowed distance of lucifer yellow diffusion (P<0. 01), and increased MMP2 activity (P<0. 01). ARP-100 attenuated H/R-induced gap junction dysfunction (P<0. 05). The arrhythmia score was also reduced after perfusion with ARP-100 (P<0. 01). CONCLUSION: H/R-treated rat CFs can inhibit gap junction between cardiomyocytes, and its mechanism may involve increased MMP2 activity. [ABSTRACT FROM AUTHOR]

The calculation models of combustion and turbulent flow are established for a spark-ignition rotary engine in order to realize dynamic simulation of operating process of natural gas-fueled rotary engine. The evolution processes of flow and temperature fields and the propagation process of flame in cylinder are obtained by numerical simulation, and the effects of different ignition advance angles on the flame propagation are analyzed under the same ignition. The results show that the eddy in cylinder can largely accelerate the flame propagation speed. When the spark plug begins to ignite, it is best to be located at the transition region between eddy zone and unidirectional flow. With the motion of rotor, the eddy is extruded and disappears because the volume of combustion chamber decreases. The ignition advance angle should be appropriately increased for making full use of the eddy action time under the constant eddy disappearance moment condition. Under the computational conditions, when the ignition advance angle is 47°, the combustion efficiency and the peak pressure in the cylinder are the highest, and the lower NO, exhaust is also taken into consideration. This study provides some theoretical guidance for the determination of best ignition advance angles under different working conditions. [ABSTRACT FROM AUTHOR]

A feed-forward Simulink model for hybrid electric commercial vehicle is established, considering the basic dynamic features of its components. Dynamic programming (DP) theory is adopted to find the optimal control strategies for vehicle fuel economy including the strategy of power split between engine and motor and the shift control strategy. Improved control rules for vehicle control are extracted based on DP optimal control results and implemented as the control strategy. The results of simulation over the heavy-duty vehicle cycle from natural driving statistics demonstrate the potential of improved vehicle control strategy based on DP optimization technique in significantly enhancing fuel economy. [ABSTRACT FROM AUTHOR]

Objective: To investigate the association between follicle size on human chorionic gonadotropin (hCG) day and clinical pregnancy rate in cycles with clomiphene citrate. Methods: 212 infertile couples who accepted artificial insemination with donor semen treatment cycles were evaluated retrospectively in this study. They were divided into four groups according to the diameter of leading follicle on the day of hCG injection: group A (18-19.5 mm), group B (20-21.5 mm), group C (22-23.5 mm) and group D (above 24 mm). The pregnancy outcomes were compared. Results: The pregnancy rates of four groups were 24.39%, 14.29%, 18.18% and 7.14%. There was not significant difference among the four groups (P > 0.05). Conclusions: There is not association between pregnancy rate of AID in cycles with clomiphene citrate and follicle size on hCG day according to our present study. [ABSTRACT FROM AUTHOR]