Search Results

You are looking at 1 - 4 of 4 items for

  • Author: Lei Han x
Clear All Modify Search
Open access

Ye Tian, Han Deng, Lei Han, Sijun Hu and Xingshun Qi

Abstract

Budd-Chiari syndrome (BCS) leads to the development of liver fibrosis in most of the cases. However, the mechanism of BCS-related liver fibrosis is unclear, and it may be largely different from that induced by chronic viral hepatitis. Hepatic stellate cell (HSC) and its specific marker CD248/endosialin are known to play an important regulatory role in the development of liver fibrosis. Additionally, hypoxia microenvironment and hypoxia-inducible factor (HIF) are involved in the regulation of CD248/endosialin. Therefore, we hypothesize that hypoxia microenvironment which develops due to BCS can regulate the expression of CD248/endosialin in HSC via HIF signaling pathway, which then affects the function of HSC and development of liver fibrosis. To confirm the hypothesis, two major investigations are necessary: (1) in the BCS animal model and clinical studies, the relationship between the severity of liver fibrosis and the expression of HIF and CD248/endosialin in HSC will be explored; and (2) in the in vitro cell system, the effect of hypoxic microenvironment, HIF-1α or HIF-2α, on the expression of CD248/endosialin in HSC will be explored. It will be important to elucidate whether HIF signaling pathway regulates the expression of CD248/endosialin, thereby inducing the development of BCS-related liver fibrosis.

Open access

Brenda Wing Han Chan and Chi Tong Lei

Abstract

A Security Door Access Control System (SDACS) project involves a number of teams from different organizations with diverse project goals. One of the main challenges of such projects is the lack of a standard approach or common understanding to achieve a common goal among project parties. This research examines various management concerns for SDACS projects, highlights the expected common understanding for project participants, develops the project management constructs, and emphasizes on the resulting value of the project to all participants. A two-stage process of scale development and validation was conducted. First, six generic constructs were identified based on the Security Access Control System Framework. Next, a multi-item scale for each construct was developed with reference to the Result-Oriented Management Framework. Expert judges were invited to conduct manual sorting of the items iteratively until reliability and validity was reached. In the next stage, further refinement and validation were carried out with a synthesized survey instrument and a series of statistical testing followed. The finalized SDACS project management constructs and the related findings help reinforce the importance of a standardized management practice for SDACS projects. The value of this research not only benefits SDACS project managers but everyone who works on the project.

Open access

Zheng Yu, Lei Yan, Ning Han and Jinhao Liu

Abstract

In this paper the image fusion algorithm based on Contourlet transform and Pulse Coupled Neural Network (PCNN) was proposed to improve the performance of the image fusion in the detection accuracy of obstacles in forests. At the same time, the wavelet transform and the Principal Component Analysis (PCA) were simulated for comparison with the proposed algorithm. Then visible and infrared thermal images were collected in a forest. The experimental results have shown that the fused images using the method proposed provided a better understanding of the reality, enhanced images’ clarity and eliminated factors which provided shelters for targets.

Open access

Peng-Fei Han, Zhi-Liang Zhang, Tao-Yu Chen, Rui-Peng Zhao, Rong Zhang, Xiao-Dong Li, Peng-Cui Li, Lei Wei, Zhi Lv and Xiao-Chun Wei

Abstract

The main pathological change in post-traumatic osteoarthritis (PTOA) is cartilage degeneration, which is closely related to inflammation and oxidative stress. Inflammation can cause degeneration of articular cartilage. Cartilage degeneration can also stimulate the progression of inflammation. It has been found that inflammatory cytokines can participate in the pathological process of cartilage degeneration through multiple signaling pathways, mainly mitogen-activated protein kinase, nuclear transcription factor kappa B, and Wnt–β-catenin signal transduction pathways. This review aimed at exploring the relationship between PTOA and inflammation-related cytokines by introducing the role of proinflammatory cytokines in chondrocyte destruction and extracellular matrix degradation.