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  • Author: Jing Lei x
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Image Reconstruction Method with the Exploitation of the Spatial Correlation for Electrical Capacitance Tomography

Abstract

Electrical capacitance tomography (ECT) is considered to be a competitive measurement method. The imaging objects in ECT measurements are often in a time-varying process, and exploiting the prior information related to the dynamic nature is important for reconstructing high-quality images. Different from existing reconstruction models, in this paper a new model that incorporates the spatial correlation of the pixels by introducing the radial basis function (RBF) method, the dynamic behaviors of a timevarying imaging object, and the ECT measurement information is proposed to formulate the dynamic imaging problem. An objective functional that exploits the spatial correlation of the pixels, the combinational regularizer of the first-order total variation (FOTV) and the second-order total variation (SOTV), the multi-scale regularization, the spatial constraint, and the temporal correlation is proposed to convert the ECT imaging task into an optimization problem. A split Bregman iteration (SBI) method based iteration scheme is developed for solving the proposed objective functional. Numerical simulation results validate the superiority of the proposed reconstruction method on the improvement of the imaging quality.

Open access
Domain Ⅲ of Dengue Virus Serotype 2 Envelope: Expression at High Levels in Escherichia coli and Competitive Inhibition of Virus Entry

Abstract

Obejective The domain Ⅲ of dengue virus type 2 envelope was cloned and expressed in Escherichia coli and the recombinant protein inhibited virus effect was tested.

Methods In this study, the domain Ⅲ (DⅢ) protein of the dengue virus type-2 (DENV-2) envelope (E) antigen was expressed in Escherichia coli by fusion with a carrier protein. The protein was purified using enzymatic cleavage and affinity purification. Rabbit immunization and antibody detection was carried out. Inhibition of DENV-2 infection was observed by DENV-2 EDⅢ protein and its immunity rabbits serum.

Results The recombinant expression DENV-2 EDⅢ protein plasmid was constructed successfully. After isopropyl thiogalactoside induction, a specific soluble 29 kD protein was obtained, and the expression product accounted for 68.87% of the total protein of the cell lysate. Western blotting demonstrated the reactivity of the recombinant protein with his-tag and DENV (Ⅰ-Ⅳ) monoclonal antibodies. The protein was purified using enzymatic cleavage and affinity purification. The purified recombinant EDⅢ protein inhibited the entry of DENV-2 into BHK-21 cells. DENV-2 plaque neutralization assays were carried out using serially diluted antibodies against EDⅢ protein. At a 1:16 dilution, the antibodies produced at least 90% neutralization of the DENV-2 virus. Furthermore, the antibodies continued to exhibit high neutralization effects (approximately 80%) until the anti-EDⅢ antibody titer reached 1:1 024.

Conclusions DENV-2 EDⅢ was cloned and expressed successfully. DENV-2 EDⅢ protein could be useful in the development of inexpensive dengue vaccine. The data also suggested that DENV-2 employed an attachment molecule or receptor for its entry into C6/36 mosquito cells.

Open access
Expression of M-ficolin, H-ficolin, and L-ficolin in peripheral blood mononuclear cell of tuberculosis patients

Abstract

Background: Ficolins are lectins that have been demonstrated to play an important role in innate immune response in a variety of diseases. Mycobacterium tuberculosis (M.tb) infection can trigger a series of changes in the host. However, the role of ficolin in tuberculosis is still unclear.

Objective: We investigated the expression of ficolin in peripheral blood mononuclear cell (PBMC) in TB patients and healthy control.

Methods: Using semi-quantitative RT-PCR, western blotting, and flow cytometry, we compared the expression of M-ficolin, L-ficolin, and H-ficolin in the peripheral blood mononuclear cell (PBMC), purified monocytes, and cultured dendritic cells of TB patients with healthy volunteers as controls.

Results: M-ficolin expression in PBMC was significantly lower at both mRNA and protein levels in TB patients as compared to healthy controls. The lower M-ficolin level in TB patient PBMCs may be attributed to its lower level in monocytes. The expression levels of H-ficolin and L-ficolin in both healthy controls and TB patients were very low and they had no significant differences between the two groups.

Conclusions: Compared to healthy controls, M-ficolin expression is significantly lower in TB patients. Measurement of M-ficolin may be a potential auxiliary tool to diagnose TB infection.

Open access
Motorcycle Engine Controller Design and Matlab/ Simulink Simulation
Open access
The Effects of Fluid Viscosity on the Orifice Rotameter

Abstract

Due to the viscous shear stress, there is an obvious error between the real flow rate and the rotameter indication for measuring viscous fluid medium. At 50 cSt the maximum error of DN40 orifice rotameter is up to 35 %. The fluid viscosity effects on the orifice rotameter are investigated using experimental and theoretical models. Wall jet and concentric annulus laminar theories were adapted to study the influence of viscosity. And a new formula is obtained for calculating the flow rate of viscous fluid. The experimental data were analyzed and compared with the calculated results. At high viscosity the maximum theoretical results error is 6.3 %, indicating that the proposed measurement model has very good applicability.

Open access
Electro-acupuncture on Nei Guan and Bai Hui: How Does It Affect GRP78 and Caspase-12 Gene Expression in Rats with Ischemia-Reperfusion Injury

Abstract

Objective: To observe the effects of electro-acupuncture (EA) on GRP78 and Caspase-12 gene expression in rats with ischemia- reperfusion injury (IRI) by stimulation on Nei Guan (PC6) and Bai Hui (GV20) points, so that to understand whether or not the protective effects of acupuncture is related to endocytoplasmic reticulum (ER) stressapoptosis passage.

Methods: 50 rats were randomly assigned to five groups (10 in each group): normal control(A), pseudo-operation(B), operation(C), Edaravone(D) and EA(E). The ischemia/reperfusion model of middle cerebral artery occlusion (MCAO) was established by suture embolic method. TUNEL staining method was employed to measure the apoptosis index of nerve cells in rats. Real-time polymerase chain reaction (RT-PCR) was employed to measure the mRNA expression of GRP78 and Caspase-12.

Results: Compared with normal group and pseudo-operation group, the apoptosis indexes and mRNA expression of GRP78 and Caspase-12 in operation group, Edaravone group and EA group were increased, with statistical significance(P<0.05 or P<0.01); compared with operation group, the apoptosis indexes and Caspase-12 mRNA expression in Edaravone group and EA group were decreased(P<0.05 or P<0.01), but GRP78 mRNA expression were increased(P<0.01); there were no significant difference between Edaravone group and EA group on the above indexes(P>0.05).

Conclusion: Acupuncture on Nei Guan and Bai Hui points could effectively suppress the nerve cell apoptosis in cerebral ischemia. The underlying mechanism might be related to upregulation of the ERS-protective GRP78 expression and downregulation of apoptosis-promotion Caspase-12 expression.

Open access
Estimating Root Zone Moisture from Surface Soil Using Limited Data

Abstract

For estimation of root-zone moisture content from EO-1/Hyperion imagery, surface soil moisture was first predicted by hyperspectral reflectance data using partial least square regression (PLSR) analysis. The textures of more than 300 soil samples extracted from a 900 m × 900 m field site located within the Hetao Irrigation District in China were used to parameterize the HYDRUS-1D numerical model. The study area was spatially discretized into 18,000 compartments (30 m × 30 m × 0.02 m), and Monte Carlo simulations were applied to generate 2000 different soil-particle size distributions for each compartment. Soil hydraulic properties for each realization were determined by application of artificial neural network analysis and used to parameterize HYDRUS-1D to simulate averaged soil-moisture contents within the root zone (0-40 cm) and surface (approximately 0-4 cm). Then the link between surface moisture and root zone was established by use of linear regression analysis, resulting in R and RMSE of 0.38 and 0.03, respectively. Kriging and co-kriging with observed surface moisture, and co-kriging with surface moisture obtained from Hyperion imagery were also used to estimate root-zone moisture. Results indicated that PLSR is a powerful tool for soil moisture estimation from hyperspectral data. Furthermore, co-kriging with observed surface moisture had the highest R (0.41) and linear regression model, and HYDRUS Monte Carlo simulations had a lowest RMSE (0.03) among the four methods. In regions that have similar climatic and soil conditions to our study area, a linear regression model with HYDRUS Monte Carlo simulations is a practical method for root-zone moisture estimation before sowing and it can be easily coupled with remote sensing technology.

Open access
Treatment of nasopharyngeal carcinoma using simultaneous modulated accelerated radiation therapy via helical tomotherapy: a phase II study

Abstract

Background

The aim of the study was to evaluate short-term safety and efficacy of simultaneous modulated accelerated radiation therapy (SMART) delivered via helical tomotherapy in patients with nasopharyngeal carcinoma (NPC).

Methods

Between August 2011 and September 2013, 132 newly diagnosed NPC patients were enrolled for a prospective phase II study. The prescription doses delivered to the gross tumor volume (pGTVnx) and positive lymph nodes (pGTVnd), the high risk planning target volume (PTV1), and the low risk planning target volume (PTV2), were 67.5 Gy (2.25 Gy/F), 60 Gy (2.0 Gy/F), and 54 Gy (1.8 Gy/F), in 30 fractions, respectively. Acute toxicities were evaluated according to the established RTOG/EORTC criteria. This group of patients was compared with the 190 patients in the retrospective P70 study, who were treated between September 2004 and August 2009 with helical tomotherapy, with a dose of 70-74 Gy/33F/6.5W delivered to pGTVnx and pGTVnd.

Results

The median follow-up was 23.7 (12–38) months. Acute radiation related side-effects were mainly problems graded as 1 or 2. Only a small number of patients suffered from grade 4 leucopenia (4.5%) or thrombocytopenia (2.3%). The local relapse-free survival (LRFS), nodal relapse-free survival (NRFS), local-nodal relapse-free survival (LNRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were 96.7%, 95.5%, 92.2%, 92.7% and 93.2%, at 2 years, respectively, with no significant difference compared with the P70 study.

Conclusions

Smart delivered via the helical tomotherapy technique appears to be associated with an acceptable acute toxicity profile and favorable short-term outcomes for patients with NPC. Long-term toxicities and patient outcomes are under investigation.

Open access
Effects of Water Intake Layout along the Wharf Shoreline on Ships

Abstract

The construction of a water intake along the wharf shoreline can realise the intensive and comprehensive utilisation of the shoreline. However, since the water intake will increase the lateral flow at the wharf and also the hydrodynamic forces on ships, it will bring risks to ships mooring and leaving. The effects of the water intake on ships are studied using a physical model, numerical model and standard formulas. The results show that it leads to an increase of the hydrodynamic forces acting on the ship when the standard formulas are used to calculate the forces without considering the water level difference between the two sides of the ship. The results of the physical model are closer to the real situation. Measures that can effectively reduce the influence of the water intake on ships are proposed by increasing the distance between the wharf front and the front of the water intake as well as the depth of the water inlet windows.

Open access
The Predictive Value of On-treatment Virological Response for Sustained Virological Response in Chronic Hepatitis C Patients Receiving a Personalized Treatment Program

Abstract

Objective To investigate the effects of individualised treatment with peginterferon alpha-2a (40 kD) plus ribavirin in Chinese patients with CHC.

Methods Total of 297 consecutive Chinese patients were enrolled, including 250 naïve cases and 47 cases who were previously treated. Treatment duration was determined according to viral genotypes, prior treatment history and viral responses at week 4, 12 and 24.

Results Totally, 235 patients (79.1%) completed treatment and 186 (87.3%) achieved SVR. And 219 out of 289 (75.8%) patients achieved HCV RNA negative at week 4 (RVR) and 259 of 276 (93.8%) at week 12. Among the 164 patients with RVR who completed follow-up, 158 (96.3%) achieved SVR. Patients with RVR had lower baseline viral loads than patients without RVR (P = 0.034). The positive predictive value (PPV) of RVR for SVR was 90.7% (OR 2.10 vs. non-RVR, 95% CI: 0.50 - 8.7). Similar outcomes were observed among patients with HCV undetectable at week 12.

Conclusions Complete viral suppression by week 4 is associated with a high rate of treatment success in treatment naïve and experienced patients receiving individualized CHC therapy.

Open access