Search Results

You are looking at 1 - 10 of 33 items for

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

Li Han

Abstract

The harms of seasonal flu and global pandemic influenza have generally attracted attention. However, the currently administered influenza drugs and flu vaccines have certain limitations. Since the discovery of the small interfering RNA (siRNA) and its mediated RNA interference process, this molecule has been widely used in the study of anti-influenza viral infections because of its high specificity and strong selectivity. The results provided new concepts for the prevention and treatment of influenza virus. However, the siRNA still faces an enormous challenge despite extensive studies on this molecule. The research progress of siRNA in anti-influenza viral infection was reviewed in this study.

Open access

Li Han

Abstract

Chlamydia trachomatis (Ct) infection can induce host cells to produce numerous cytokines. Cytokines play important roles in inflammatory response. Although inflammation can protect the body, persistent inflammation can lead to pathological changes and tissue damages. Further research should determine whether cytokine production directly affects development and outcomes of inflammation. This study summarizes Ct infection and related cytokines.

Open access

Yingbo Li, Anton Kummert, Fritz Boschen and Hans Herzog

Interpolation-Based Reconstruction Methods for Tomographic Imaging in 3D Positron Emission Tomography

Positron Emission Tomography (PET) is considered a key diagnostic tool in neuroscience, by means of which valuable insight into the metabolism function in vivo may be gained. Due to the underlying physical nature of PET, 3D imaging techniques in terms of a 3D measuring mode are intrinsically demanded to assure satisfying resolutions of the reconstructed images. However, incorporating additional cross-plane measurements, which are specific for the 3D measuring mode, usually imposes an excessive amount of projection data and significantly complicates the reconstruction procedure. For this reason, interpolation-based reconstruction methods deserve a thorough investigation, whose crucial parts are the interpolating processes in the 3D frequency domain. The benefit of such approaches is apparently short reconstruction duration, which can, however, only be achieved at the expense of accepting the inaccuracies associated with the interpolating process. In the present paper, two distinct approaches to the realization of the interpolating procedure are proposed and analyzed. The first one refers to a direct approach based on linear averaging (inverse distance weighting), and the second one refers to an indirect approach based on two-dimensional convolution (gridding method). In particular, attention is paid to two aspects of the gridding method. The first aspect is the choice of the two-dimensional convolution function applied, and the second one is the correct discretization of the underlying continuous convolution. In this respect, the geometrical structure named the Voronoi diagram and its computational construction are considered. At the end, results of performed simulation studies are presented and discussed.

Open access

Xiaofeng Han, Yan Li and Guodong Liu

Abstract

This paper analyzes the requirements of the information transmission network of ship integrated condition monitoring system, and proposes a design scheme of ship condition monitoring system based on wireless ad hoc network. The wireless ad hoc network protocol was designed, its networking process was analyzed in detail, and the network transmission performance of the monitoring system was tested. The results proved the feasibility of the system. The above solution can be used for the transmission of ship state information that satisfies the requirements of wireless transmission, and has important theoretical and practical significance. The slot allocation algorithm has been receiving extensive attention as an important part of the TDMA system research. This paper analyzes the summarization and summarization of TDMA time slot assignment algorithms from several aspects such as slot synchronization, existing slot allocation algorithm, and slot assignment model, laying an important foundation for researchers to do further research. In the TDMA system, time is divided into non-overlapping time frames, and the time frames are divided into non-overlapping time slots. Each node in the network performs corresponding operations in each time slot.

Open access

Yong Liao, Zhen-Nan Fan, Li Han and Li-Dan Xie

Abstract

In order to research the losses and heat of damper bars thoroughly, a multislice moving electromagnetic field-circuit coupling FE model of tubular hydro-generator and a 3D temperature field FE model of the rotor are built respectively. The factors such as rotor motion and non-linearity of the time-varying electromagnetic field, the stator slots skew, the anisotropic heat conduction of the rotor core lamination and different heat dissipation conditions on the windward and lee side of the poles are considered. Furthermore, according to the different operating conditions, different rotor structures and materials, compositive calculations about the losses and temperatures of the damper bars of a 36 MW generator are carried out, and the data are compared with the test. The results show that the computation precision is satisfied and the generator design is reasonable.

Open access

Lidong Liu, Jifeng Hu, Zishu He, Chunlin Han, Huiyong Li and Jun Li

A Velocity Measurement Method Based on Scaling Parameter Estimation of a Chaotic System

In this paper, we propose a new method of measuring the target velocity by estimating the scaling parameter of a chaos-generating system. First, we derive the relation between the target velocity and the scaling parameter of the chaos-generating system. Then a new method for scaling parameter estimation of the chaotic system is proposed by exploiting the chaotic synchronization property. Finally, numerical simulations show the effectiveness of the proposed method in target velocity measurement.

Open access

Guang-Hou Zhou, Li Han, Zhen-Nan Fan, Yong Liao and Song Huang

Abstract

To study the principle of loss and heat at the end region of large 4-poles nuclear power turbine generator, 3D transient electromagnetic field and 3D steady temperature field finite element (FE) models of the end region are established respectively. Considering the factors such as rotor motion, core non-linearity and time-varying of electromagnetic field, the anisotropic heat conductivity and different heat dissipation conditions of stator end region, a 50 Hz, 1150 MW, 4-poles nuclear power turbine generator is investigated. The loss and heat at the generator end region are calculated respectively at no-load and rated-load, and the calculation results are compared with the test data. The result shows that the calculation model is accurate and the generator design is suitable. The method is valuable for the research of loss and heat at the end region of large 4-poles nuclear power turbine generator and the improvement of the generator’s operation stability. The method has been applied successfully for the design of the larger nuclear power turbine generators

Open access

Yong Han, Bingyi Shi, Ming Cai, Xiaoguang Xu, Liang Xu, Qiang Wang, Wenqiang Zhou and Li Xiao

CD20 Expression in the Transplanted Kidney of Patients with Graft Loss and Transient Allograft Dysfunction

This study aimed to explore the relationship between the infiltration of CD20+ B cells and the survival time of a renal allograft and to investigate the role of infiltrated B cells in the rejection of the renal allograft. A total of 40 patients with renal allograft loss due to refractory rejection and 20 patients with transient renal allograft dysfunction were recruited. Renal biopsy was done and CD20 expression was detected by immunohistochemistry. In addition, the survival time of the renal allograft was also obtained. The relationships between the CD20 expression and the survival time of the renal allograft and graft loss due to rejection were analyzed. The associations of gender, age and clinicopathogical types with the CD20 expression were also investigated. The proportion of patients positive for CD20 in the transplanted kidney was higher in patients receiving nephrectomy of the allograft due to rejection than in those with transient allograft dysfunction. The diffuse infiltration of CD20+ B cells was considered as positive staining. In 40 samples from patients with graft loss, 19 had diffuse infiltration of CD20+ B cells (47.5%). In 19 patients positive for CD20, hyperacute rejection was found in 1 patient, acute rejection in 5 and chronic rejection in 13. Statistical analysis showed the CD20 expression was not associated with the age and gender of donors and recipients, regimen for immunosuppressive treatment, cold/warm ischemia time and secondary transplantation. CD20+ B cell infiltration predicts a poor prognosis of patients with kidney transplantation and is one of the risk factors of graft loss.