SOME GLOBAL CONVERGENCE PROPERTIES OF THE LEVENBERG-MARQUARDT METHODS WITH LINE SEARCH

Du, Shou-Qiang The Korean Society for Computational and Applied M 2013 Journal of applied mathematics & informatics Vol.31 No.3

In this paper, we consider two kinds of the Levenberg-Marquardt method for solve a system of nonlinear equations. We use line search on every iteration to guarantee that the Levenberg-Marquardt methods are globally convergent. Under mild conditions, we prove that while the de- scent condition can be satisfied at the iteration of the Levenberg-Marquardt method, the global convergence of the method can be established.

Establishment of and Comparison between Orthotopic Xenograft and Subcutaneous Xenograft Models of Gallbladder Carcinoma

Du, Qiang,Jiang, Lei,Wang, Xiao-Qian,Pan, Wei,She, Fei-Fei,Chen, Yan-Ling Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.8

Background: Gallbladder carcinoma (GBC) is the most common carcinoma of the biliary system. Among its research models, orthotopic xenograft models, important research tools, have been rarely reported in the literature however. Aim: To explore establishment of an orthotopic xenograft model and to evaluate the advantage and disadvantage as compared with other models. Materials and Methods: Subcutaneous xenograft and orthotopic xenograft models of gallbladder carcinoma in nude mice were established and compared with human gallbladder carcinomas. Results: For the orthotopic xenograft model and clinical gallbladder carcinomas, the lymph node metastatic rates were 69.2% and 53.3% (p>0.05); ascites generation rates, 38.5% and 11.7%(p<0.05); liver invasive rates, 100% and 61.7%(p<0.05); and lymphatic vessel densities (LVD), $10.4{\pm}3.02$ and $8.77{\pm}2.92$ (p>0.05), respectively. In the subcutaneous xenograft model, no evidence of ascites generation, lymph node metastasis and liver metastasis were found, and its LVD was lower ($4.56{\pm}1.53$, p<0.05). Conclusions: Compared with the subcutaneous xenograft model, the orthotopic xenograft model better simulates clinical gallbladder carcinoma in terms of metastasis and invasion, which may be attributed to the difference in microenvironment and LVD.

Some Global Convergence Properties of the Levenberg-Marquardt Methods with Line Search

Shou-qiang Du 한국전산응용수학회 2013 Journal of applied mathematics & informatics Vol.31 No.3

In this paper, we consider two kinds of the Levenberg-Marquardt method for solve a system of nonlinear equations. We use line search on every iteration to guarantee that the Levenberg-Marquardt methods are globally convergent. Under mild conditions, we prove that while the descent condition can be satisfied at the iteration of the Levenberg-Marquardt method, the global convergence of the method can be established.

Dynamic Parameter of the Load-unload Response Ratio and it`s Application in Prediction of Debris Landslides

( Qiang He Ke ),( Shang Qing Wang ),( Wen Du ),( Si Jing Wang ) 대한지질공학회 2007 국제학술발표회 논문집 Vol.2007 No.-

A weight optimization method for chemical safety evaluation indicators based on the bipartite graph and random walk

Du Junwei,Jing Guanghui,Hu Qiang 한국CDE학회 2022 Journal of computational design and engineering Vol.9 No.4

In the chemical safety evaluation system, the optimization of indicator weights needs to take both experts’ evaluations and the feedback on accident influences into account. Thus, this paper proposes a comprehensive weighting method based on the association bipartite graph (ABG). The accident influences and correlation intensity between the accident and the evaluation indicators are calculated on the ABG. A random walk algorithm, which integrates the objective influences of the accidents and the subjective evaluations of experts, is designed to realize the weight optimization. Experiments prove the effectiveness of the proposed method from the perspectives of weight ranking and fitting degree.

Robotic Path Planning Based on Episodic-cognitive Map

Qiang Zou,Ming Cong,Dong Liu,Yu Du 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.5

Inspired by mammal’s spatial awareness and navigation capabilities, a new episodic-cognitive map buildingand path planning method was proposed, used for navigation tasks of mobile robot under the unstructured environment. Combined with characteristic of cognitive map and simulated the formation mechanism of episodicmemory in the hippocampus, a novel episodic-cognitive map encapsulated the information of scene perception,state neuron and pose perception was built, realized the real-time, incremental accumulative and updating cognitionof the robot to the environment. Based on the episodic-cognitive map, using the minimum distance between events,an algorithm of the event sequence planning was put forward for preferred trajectory choosing. Experimental resultsshowed that the proposed algorithms realized the mobile robot choose the preferred planning path, and using theSIFT-based visual navigation method, the mobile robot can reach the target very well. The method in this paperextended the application of biological cognition theory in the field of robotic planning.

Personal Safety in Electromagnetic Environment of Electric Vehicle

Cheng Qiang,Du Zhong-min 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.6

With the extensive application of automotive electrical and electronic equipment, issues of electromagnetic radiation and electromagnetic compatibility have become increasingly prominent, human body in complex automotive electromagnetic environment is bound to be some damage of electromagnetic radiation. This paper established a relatively sophisticated car simulation model,through electromagnetic characteristics of antenna model, we got automotive electric field distribution and simulation results of human body SAR value, so conclusion can be drawn that automotive electromagnetic environment is relatively safe to passengers.

ACT001 alleviates inflammation and pyroptosis through the PPAR-γ/NF-κB signaling pathway in LPS-induced alveolar macrophages

Fu Qiang,Shen Na,Fang Tao,Zhang Hewei,Di Yanbo,Liu Xuan,Du Chao,Guo Jianshuang 한국유전학회 2024 Genes & Genomics Vol.46 No.3

Background ACT001 is an anti-inflammatory agent that has been widely investigated for its role in tumors, intracranial diseases, and fibrotic diseases, but its effect on acute lung injury is less known. Objective The purpose of this study was to investigate the effect and mechanism of ACT001 on regulating inflammation and pyroptosis in lipopolysaccharide (LPS)-induced alveolar macrophages. Methods NR8383 alveolar macrophages treated with LPS were used to replicate the proinflammatory macrophage phenotype observed during acute lung injury. After ACT001 treatment, we measured the secretion and expression levels of critical inflammatory cytokines, the rate of pyroptosis, and the expression of NLRP3 inflammasome-associated proteins and pyroptosis-associated proteins. In addition, we assessed the role of the PPAR-γ/NF-κB signaling pathways and further validated the results with a PPAR-γ inhibitor. Results Our findings confirmed that ACT001 reduced the expression and release of inflammatory factors, attenuated cell pyroptosis, and downregulated the expression of NLRP3, ASC, caspase-1 p20, and GSDMD-N. These effects may be achieved by activating PPAR-γ expression and then inhibiting the NF-κB signaling pathway. When macrophages were treated with the PPAR-γ inhibitor, the protective effects of ACT001 were reversed. Conclusion ACT001 significantly ameliorated inflammation and pyroptosis via the PPAR-γ/NF-κB signaling pathways in LPS-induced NR8383 alveolar macrophages. Background ACT001 is an anti-inflammatory agent that has been widely investigated for its role in tumors, intracranial diseases, and fibrotic diseases, but its effect on acute lung injury is less known. Objective The purpose of this study was to investigate the effect and mechanism of ACT001 on regulating inflammation and pyroptosis in lipopolysaccharide (LPS)-induced alveolar macrophages. Methods NR8383 alveolar macrophages treated with LPS were used to replicate the proinflammatory macrophage phenotype observed during acute lung injury. After ACT001 treatment, we measured the secretion and expression levels of critical inflammatory cytokines, the rate of pyroptosis, and the expression of NLRP3 inflammasome-associated proteins and pyroptosis-associated proteins. In addition, we assessed the role of the PPAR-γ/NF-κB signaling pathways and further validated the results with a PPAR-γ inhibitor. Results Our findings confirmed that ACT001 reduced the expression and release of inflammatory factors, attenuated cell pyroptosis, and downregulated the expression of NLRP3, ASC, caspase-1 p20, and GSDMD-N. These effects may be achieved by activating PPAR-γ expression and then inhibiting the NF-κB signaling pathway. When macrophages were treated with the PPAR-γ inhibitor, the protective effects of ACT001 were reversed. Conclusion ACT001 significantly ameliorated inflammation and pyroptosis via the PPAR-γ/NF-κB signaling pathways in LPS-induced NR8383 alveolar macrophages.

Variations in bacterial and fungal communities through soil depth profiles in a Betula albosinensis forest

Can Du,Zengchao Geng,Qiang Wang,Tongtong Zhang,Wenxiang He,Lin Hou,Yueling Wang 한국미생물학회 2017 The journal of microbiology Vol.55 No.9

Microbial communities in subsurface soil are specialized for their environment, which is distinct from that of the surface communities. However, little is known about the microbial communities (bacteria and fungi) that exist in the deeper soil horizons. Vertical changes in microbial alpha-diversity (Chao1 and Shannon indices) and community composition were investigated at four soil depths (0–10, 10–20, 20–40, and 40–60 cm) in a natural secondary forest of Betula albosinensis by high-throughput sequencing of the 16S and internal transcribed spacer rDNA regions. The numbers of operational taxonomic units (OTUs), and the Chao1 and Shannon indices decreased in the deeper soil layers. Each soil layer contained both mutual and specific OTUs. In the 40–60 cm soil layer, 175 and 235 specific bacterial and fungal OTUs were identified, respectively. Acidobacteria was the most dominant bacterial group in all four soil layers, but reached its maximum at 40–60 cm (62.88%). In particular, the 40–60 cm soil layer typically showed the highest abundance of the fungal genus Inocybe (47.46%). The Chao1 and Shannon indices were significantly correlated with the soil organic carbon content. Redundancy analysis indicated that the bacterial communities were closely correlated with soil organic carbon content (P = 0.001). Collectively, these results indicate that soil nutrients alter the microbial diversity and relative abundance and affect the microbial composition.

Ankrd7, a Novel Gene Specifically Expressed in Sertoli Cells and Its Potential Roles in Sertoli Cell Maturation

Yu-Qiang Shi,Lian-Cai Du,Qing-Zhong Wang,Chun-Fang Han 한국분자세포생물학회 2009 Molecules and cells Vol.27 No.2

The somatic Sertoli cells play an essential role in testis determination and spermatogenesis by providing nutrition and structural support. In the current study, we report on the novel Ankrd7 gene that contains five ankyrin repeat domains. This gene was specifically expressed in Sertoli cells and was regulated in a maturation-dependent manner. Its expression was restricted to testicular tissue, and its mRNA could be detected in testes at as early as 14 dpp (days post partum) using RT-PCR analysis. In both testicular tissue sections and in vitro cultured Sertoli cells, the Ankrd7 protein was localized to the nucleus of the Sertoli cell. Immunohistochemistry and immunocytochemistry investigations showed that the protein was detectable in testicular tissues at 20 dpp, at which time Sertoli cells were gradually differentiating into their mature cellular form. These results suggest that Ankrd7 is probably involved in the process of Sertoli cell maturation and in spermatogenesis.