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  • Author: Jin Zhang x
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Abstract

Brucellosis is one of the most prevalent zoonoses in the world. Incidence of the disease has increased significantly in recent years and has seriously affected the health of human beings and the development of animal husbandry. The pathogenesis of brucellosis remains unclear. Current studies suggest that this disease may be related to changes in natural killer cells, dendritic cells, and macrophages in immune cell subsets. Brucellosis may be also related to T helper (Th) 1 cell/Th2 cell imbalance in the CD4+ T cell subset, immunoregulation of regulatory T cells and Th17 cells, and the mechanism of action of CD8+ T cell. This paper aims to review the research progress on these inherent immune cells, the CD4+ T cell subset, and CD8+ T cells in Brucella infection.

Abstract

Human papillomavirus (HPV) is a DNA virus that infects the skin and mucous membranes of the human body. Approximately 80% of sexually active women are likely infected with HPV. Cervical cancer is one of the most common malignant tumors and is second in incidence only to breast cancer. Infection with high-risk HPV types is the main risk factor for cervical cancer, which is currently the only malignant tumor with a clearly defined etiology. HPV infection is also closely related to the incidence and development of other malignant tumors. In addition to cervical cancer, HPV can cause other urogenital tumors, as well as tumors in the digestive tract, lungs, eyes, skin, and other organ systems. This paper provides a review of the progress in HPV infection-related research and provides novel ideas for the study of tumor etiology and mechanisms.

Abstract

Mycoplasma pneumoniae (MP) is an important pathogen of community-acquired pneumonia in children. As a type of self-limited disease, most MP infections cause mild clinical symptoms, but they can also lead to severe pneumonia or extrapulmonary complications. The resistance rate of MP has increased in recent years. Early and rapid diagnosis of MP infection is important for the treatment and prognosis of the disease. Current methods for diagnosing MP infection include isolation culture, serological diagnosis, and molecular biological diagnosis. This review summarizes the recent research progress in the internal and external laboratory diagnoses of MP infection both at home and abroad and the advantages and disadvantages of various diagnostic methods.

Abstract

Vertical-axial tidal current turbine is the key for the energy converter, which has the advantages of simple structure, adaptability to flow and uncomplex convection device. It has become the hot point for research and application recently. At present, the study on the hydrodynamic performance of vertical-axial tidal current turbine is almost on 2-D numerical simulation, without the consideration of 3-D effect. CFD (Computational Fluid Dynamics) method and blade optimal control technique are used to improve accuracy in the prediction of tidal current turbine hydrodynamic performance. Numerical simulation of vertical-axial tidal current turbine is validated. Fixed and variable deflection angle turbine are comparatively studied to analysis the influence of 3-D effect and the character of fluid field and pressure field. The method, put the plate on the end of blade, of reduce the energy loss caused by 3-D effect is proposed. The 3-D CFD numerical model of vertical-axial tidal current turbine hydrodynamic performance in this study may provide theoretical, methodical and technical reference for the optimal design of turbine.

Abstract

Automated Incident Detection (AID) is an important part of Advanced Traffic Management and Information Systems (ATMISs). An automated incident detection system can effectively provide information on an incident, which can help initiate the required measure to reduce the influence of the incident. To accurately detect incidents in expressways, a Support Vector Machine (SVM) is used in this paper. Since the selection of optimal parameters for the SVM can improve prediction accuracy, the tabu search algorithm is employed to optimize the SVM parameters. The proposed model is evaluated with data for two freeways in China. The results show that the tabu search algorithm can effectively provide better parameter values for the SVM, and SVM models outperform Artificial Neural Networks (ANNs) in freeway incident detection.

Abstract

This study investigates the evolution of diabetics’ concerns based on the analysis of terms in the Diabetes category logs on the Yahoo! Answers website. Two sets of question-and-answer (Q&A) log data were collected: one from December 2, 2005 to December 1, 2006; the other from April 1, 2013 to March 31, 2014. Network analysis and a t-test were performed to analyze the differences in diabetics’ concerns between these two data sets. Community detection and topic evolution were used to reveal detailed changes in diabetics’ concerns in the examined period. Increases in average node degree and graph density imply that the vocabulary size that diabetics use to post questions decreases while the scope of questions has become more focused. The networks of key terms in the Q&A log data of 2005–2006 and 2013–2014 are significantly different according to the t-test analysis of the degree centrality and betweenness centrality. Specifically, there is a shift in diabetics’ focus in that they have become more concerned about daily life and other nonmedical issues, including diet, food, and nutrients. The recent changes and the evolution paths of diabetics’ concerns were visualized using an alluvial diagram. The food- and diet-related terms have become prominent, as deduced from the visualization results.

Abstract

Objective To observe the effects of HCV protein, NS3 and NS5A on IFN-β in HepG2 cells and its regulation mechanism.

Methods Human liver hepatocellular carcinoma cells HepG2 were transfected with recombinant eukaryotic plasmid pcDNA3.1/myc-His-core, NS3 or NS5A to overexpress these proteins, and the expression of IFN-β were detected by qRT-PCR, Western blotting and ELISA. Luc2P reporter plasmids pGL4.10-IFNβ-P were constructed and transfected into HepG2 cells, and the activity of IFN-β promoter were determined through luciferase assay for regulation mechanism study.

Results Both mRNA level and protein expression of IFN-β were significantly decreased (P < 0.05) in the presence of NS3 or NS5A protein. Luciferase assay revealed that NS3 or NS5A protein downregulated IFN-β promoter activity (P < 0.05). Meanwhile, HCV core protein had little effect on IFN-β expression.

Conclusions HCV protein NS3 and NS5A could inhibit innate IFN-β expression and thus escape immune selection and hinder the host immune responses.

Abstract

The objective of this paper is to evaluate the self- healing properties of a commercially-available geosynthetic clay liner (GCL) using flexible-wall permeameter. The GCLs are produced by the same factory, but the contents of bentonite are different. Also the hydraulic conductivities (HC) of GCLs with no defect are different. In this study, specimens were completely saturated under the backpressure of 20 kPa before the test. Permeability tests were performed on GCL specimens with penetrating flaw and also on specimens permeated with distilled water and CaCl2 solutions. The test results were presented and discussed. Experimental results showed that the GCL with penetrating flaw did not exhibit complete self-healing in the case of flaw. After 120 days, the hydraulic conductivity increased by approximately an order of magnitude. In addition, CaCl2 solutions had a significant influence on the hydraulic conductivity. The research findings might be of interest to researchers and engineers who design liners for landfills and other liquid containment facilities

Abstract

In the non-contact detection of thread profile boundary correction, it remains challenging to ensure that the thread axis intersects the CCD camera axis perpendicularly. Here, we addressed this issue using modified algorithms. We established the Cartesian coordinate system according to the spatial geometric relationship of the thread. We used the center of the bottom of the thread as the origin, and the image of the extreme position image was replaced by the image of the approximate extreme position. In addition, we analyzed the relationship between the boundary of the theoretical thread image and the theoretical profile. We calculated the coordinate transformation of the point on the theoretical tooth profile and the coordinate function of the point on the boundary of the theoretical image. At the same time, the extreme value of the function was obtained, and the boundary equation of the theoretical thread image was deduced. The difference equation between the two functions was used to correct the boundary point of the actual thread image, and the fitting results were used to detect the key parameters of the external thread of the cylinder. Further experiment proves that the above algorithm effectively improves the detection accuracy of thread quality, and the detection error of main geometric parameters is reduced by more than 50 %.

Abstract

Research methods play an extremely important role in studies. Statistical methods are fundamental and vital for quantitative research. The authors of this paper investigated the research papers that used statistical methods including parametric inferential statistical methods, nonparametric inferential statistical methods, predictive statistical correlation methods, and predictive statistical regression methods in library and information science and examined the connections and interactions between statistical methods and their application areas including information creation, information selection and control, information organization, information retrieval, information dissemination, and information use. Both an inferential statistical method and graphic clustering visualization method were employed to explore the relationships between statistical methods and application areas and reveal the hidden interaction patterns. As a result, 1821 research papers employing statistical methods were identified among the papers published in six major library and information science journals from 1999 to 2017. The findings showed that application areas affected the types of statistical methods utilized. Studies in information organization and information retrieval tended to employ parametric and nonparametric inferential methods, while correlation and regression methods were applied more in studies in information use, information dissemination, information creation, and information selection and control field. These findings help researchers better understand the statistical method orientation of library and information science studies and assist educators in the field to develop applicable quantitative research methodology courses.