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In order to study the comprehensive influence of factors such as contact between resident birds and poultry, poultry recruitment, environment and other factors on the transmission and control of H5 subtype avian influenza virus, a dynamic model of resident birds and poultry is developed. First, the basic reproduction number R 0 is obtained. When R 0 > 1 , the dynamic model have a unique positive equilibrium and the disease persisted. Second, the Lyapunov functions is constructed to determine the global stability of the disease-free equilibrium and the endemic equilibrium. The results of numerical simulation show that regular disinfection and sterilization can increase the mortality of virus and effectively prevent the occurrence of epidemic situation. Although closing the live poultry trading market is not the main measure to control the epidemic, but it can control the epidemic to a lower level. Therefore, the regular closure of trading markets and sterilization can prevent and control the spread of the epidemic. [ABSTRACT FROM AUTHOR]

Brucellosis, a zoonotic disease, has brought about enormous human suffering and tremendous economic burden to animal husbandry in China. However, Inner Mongolia is the hardest hit area of brucellosis in China. A total of 132,037 human cases have been reported from 2010 to 2020. Endogenous mechanisms of brucellosis spreading across Inner Mongolia till remains to be revealed. We propose a periodic epidemic model to investigate the effect of periodic parameter changes on brucellosis epidemics. Then we evaluate the basic reproduction number R 0 and analyze the global dynamics of the model. Furthermore, key parameters related to periodic transmission are estimated based on the monthly data of human brucellosis cases and the trend of newly infected human brucellosis cases are predicted in Inner Mongolia. Our modeling results illustrate that periodical birth and sheep shearing play a significant role in inducing periodical outbreak of brucellosis in Inner Mongolia. Moreover, it is exhibited that the annual peak number and the final scale of human brucellosis cases will be reduced dramatically with the delayed peak time of sheep birth. While the annual peak time will be lagged and the annual peak number will be decreased as the peak time of sheep shearing is postponed. In addition, we discover that it is difficult to stem brucellosis even if all sheep are vaccinated besides ewes. Nevertheless, the detection rate exceed a certain value 0.032 or the decaying rate of Brucella surpass a critical value 0.585, the human brucellosis can be regulated in Inner Mongolia according to the sensitivity analysis of R 0 . The insights shed herein may contribute to the careful implementation of brucellosis control strategies in other regions. [ABSTRACT FROM AUTHOR]

Brucellosis a the serious infectious disease in Hinggan League. Research has demonstrated that a large amount of transportation is one of the main reasons for so many cases. However, the specific transmission mechanism of brucellosis is not clear. In this paper, we utilize a multi-patch model to study the effect of the transportation of sheep on the spread of brucellosis in Hinggan League. Theoretically, we prove the global stability of the disease-free equilibrium and the uniform persistence of the endemic equilibrium. In a practical application, we apply the model to investigate the spread of brucellosis in Ulanhot city and Jalaid Banner, which are geographically adjacent in Hinggan League. The strains carried by humans are B.melitensis bv.1 and B.melitensis bv.3. We use the two-patch model to fit reported brucellosis cases data of two places by Markov Chain Monte Carlo (MCMC) simulations. It is found that the global basic reproduction number R 0 is larger than 1, but the isolated basic reproduction numbers in Ulanhot city and Jalaid Banner are both less than 1. This indicates that the prevalence of brucellosis may be caused by the transportation of sheep. Sensitivity analysis of parameters on R 0 shows that it is the most effective means to control the transportation of sheep from Jalaid to Ulanhot on preventing brucellosis. Moreover, we also discover that improving vaccine efficiency is an effective method compared with strengthening the vaccination coverage rate and improving the detection rate of sheep with brucellosis. Our dynamic behavior analysis of the two-patch model can provide a reference for the dynamic behavior analysis of the n-patch model, and our results provide a guide for how to control brucellosis based on transportation. [ABSTRACT FROM AUTHOR]

Since 2000, the research of uncertainty quantification (UQ) has been successfully applied in many fields and has been highly valued and strongly supported by academia and industry. This review firstly discusses the sources and the types of uncertainties and gives an overall discussion on the goal, practical significance, and basic framework of the research of UQ. Then, the core ideas and typical methods of several important UQ processes are introduced, including sensitivity analysis, uncertainty propagation, model calibration, Bayesian inference, experimental design, surrogate model, and model uncertainty analysis. [ABSTRACT FROM AUTHOR]

This paper formulates a delay model characterizing the competition between bacteria and immune system. The center manifold reduction method and the normal form theory due to Faria and Magalhaes are used to compute the normal form of the model, and the stability of two nonhyperbolic equilibria is discussed. Sensitivity analysis suggests that the growth rate of bacteria is the most sensitive parameter of the threshold parameter R0 and should be targeted in the controlling strategies. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the feasibility of applying a new quantitative image analysis method to improve breast cancer diagnosis performance using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) by integrating background parenchymal enhancement (BPE) features into the decision making process. Methods: A dataset involving 115 DCE-MRI examinations was used in this study. Each examination depicts one identified suspicious breast tumor. Among them, 75 cases were verified as malignant and 40 were benign by the biopsy results. A computer-aided detection scheme was applied to segment breast regions and the suspicious tumor depicted on the sequentially scanned MR images of each case. We then computed 18 kinetic features in which 6 were computed from the segmented breast tumor and 12 were BPE features from the background parenchymal regions (excluding the tumor). Support vector machine (SVM) based statistical learning classifiers were trained and optimized using different combinations of features that were computed either from tumor only or from both tumor and BPE. Each SVM was tested using a leave-one-case-out validation method and assessed using an area under the receiver operating characteristic curve (AUC). Results: When using kinetic features computed from tumors only, the maximum AUC is 0.865 ± 0.035. After fusing with the BPE features, AUC increased to 0.919 ± 0.029. At 90% specificity, the tumor classification sensitivity increased by 13.2%. Conclusions: The proposed quantitative BPE features provide valuable supplementary information to the kinetic features of breast tumors in DCE-MRI. Their addition to computer-aided diagnosis methodologies could improve breast cancer diagnosis based on DCE-MRI examinations. [ABSTRACT FROM AUTHOR]

Dairy cattle brucellosis is a chronic bacterial disease, which is caused by Brucella abortus and mainly characterized by abortion in dairy cattle. With the rapid development of breeding industry of milk cows in China, the infectious cases of dairy cattle brucellosis show an increasing trend. Particularly in Jilin province, the annual number of the positive cases of dairy cattle was only 3 cows in 1987, and went up to 168 cows in 2005. Based on the situation of the brucellosis infection in Jilin province, we propose an Susceptible-Exposed-Infected-Virus (SEIV) dynamical model with outside transferred amount to describe the transmission of brucellosis amongst dairy cattle in this paper. We calculate the basic reproduction number R0 and prove that the equilibria are globally stable. Moreover, using the real data of nearly 20 years in Jilin province, we estimate the parameter values in the system. As a result, we can predict the number of infections as time increases. According to the prediction for the next 30 years, we can conclude that the disease will persist if we just take existing measures. If culling, sterilizing and decreasing the number of outer importing are used together, dairy cattle brucellosis will be well controlled. [ABSTRACT FROM AUTHOR]

Abstract: Nowadays DNA microarray technology is widely used in clinical researches for generating gene expression profiles from the biological samples. Based on the gene expression data, identifying differentially expressed genes (DEGs) from two groups of phenotypes or distinct biological conditions is one of the crucial steps in the procedure of discovering disease biomarkers. However, the clinical samples usually contain multiple cell types. This heterogeneous cell population significantly affects the gene expression patterns and will mask the biological difference between two groups of compared samples. Using mixed gene expression profile of multiple cell types instead of that of interested cell type for the identification of DEGs will seriously decrease the sensitivity of discovering the disease-related genes. Therefore, we proposed nonnegative matrix factorization (NMF), an unsupervised learning method that has been successfully applied in bioinformatics researches, for extracting the actual gene expression profile of interested cell type from the mixed profile of heterogeneous cell population. In our study, we firstly evaluated the performance of NMF algorithm in the deconvolution of gene expression data by using a well-controlled data set comprising the gene expression profiles from three tissues and eleven different mixtures with known proportions. Then, NMF was applied to the human whole-blood gene expression data generated from 24 kidney transplant recipients for estimating the pure gene expression profiles of five major blood cells, which were subsequently used to identify the genes related to the acute rejection of kidney transplant. The results showed that the number of DEGs (probe sets), which were identified from each of the gene expression profiles of five blood cells between stable post-transplant kidney transplant recipients and those experiencing acute transplant rejections, was greater than that from whole-blood samples. Finally, the DEGs were uploaded to the Gene Set Enrichment Analysis (GSEA) for the enrichment of signaling pathways and gene ontology terms. We found that several enriched pathways and gene ontology terms were significantly associated with renal transplantation rejection when the uploaded DEGs were identified from the two high content blood cells, while none of pathways and gene ontology terms was enriched when the uploaded DEGs were identified from whole-blood samples. Our results indicated that using the gene expression profile of specific cell type deconvoluted by NMF can efficiently increase the sensitivity of discovering potentially disease-related genes. In addition, this unsupervised method can evaluate the pure gene expression profile of specific cell type from the mixtures with no prior knowledge of cell proportions. [Copyright &y& Elsevier]

Human rabies, an infection of the nervous system, is a major public-health problem in China. In the last 60 years (1950-2010) there had been 124,255 reported human rabies cases, an average of 2,037 cases per year. However, the factors and mechanisms behind the persistence and prevalence of human rabies have not become well understood. The monthly data of human rabies cases reported by the Chinese Ministry of Health exhibits a periodic pattern on an annual base. The cases in the summer and autumn are significantly higher than in the spring and winter. Based on this observation, we propose a susceptible, exposed, infectious, and recovered (SEIRS) model with periodic transmission rates to investigate the seasonal rabies epidemics. We evaluate the basic reproduction number R, analyze the dynamical behavior of the model, and use the model to simulate the monthly data of human rabies cases reported by the Chinese Ministry of Health. We also carry out some sensitivity analysis of the basic reproduction number R in terms of various model parameters. Moreover, we demonstrate that it is more reasonable to regard R rather than the average basic reproduction number $\bar{R}_{0}$ or the basic reproduction number $\hat{R}_{0}$ of the corresponding autonomous system as a threshold for the disease. Finally, our studies show that human rabies in China can be controlled by reducing the birth rate of dogs, increasing the immunization rate of dogs, enhancing public education and awareness about rabies, and strengthening supervision of pupils and children in the summer and autumn. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes an integrated instrumentation system for the volumetric-concentration measurement of biomass/coal/air three-phase flow in a pneumatic conveying pipeline. The system combines electrostatic sensors with capacitive sensors and incorporates data fusion techniques. As the electrostatic sensor is more sensitive to dilute pulverized coal and the capacitive sensor is more sensitive to biomass particles, both sensor techniques are integrated for the concentration measurement of biomass and pulverized coal in biomass/coal/air three-phase flow. First, the flow regime is identified through the Hilbert marginal spectrum of the electrostatic sensor output signal. Then, under certain identified flow regimes, the dual regression analysis method is applied to work out the biomass concentration and the pulverized coal concentration. The experimental result indicates that the fiducial error of the system is less than 5%, and the resolution is about 1%. [Copyright &y& Elsevier]

H7N9, a kind of subgroup of influenza viruses, has lasted for over three years in China. Although it has not yet aroused large-scale outbreak in human, it reappeared and peaked every winter. According to the obtained information and literatures, possible reasons to induce recurrence of human cases every winter can be speculated as migration of birds, temperature cycling, or reopening of live poultry trading markets. However, which one is the major driving factor is unclear. As a result, a dynamical model about migrant birds, resident birds and domestic poultry, considering temperature-dependent decay rate of virus and periodical closure of trading markets, is established to determine internal critical driving factors, and to propose the most effective prevention measure by sensitivity analysis. By numerical analysis, it is concluded that temperature cycling may be the main driving mechanism of the periodicity of infected human cases. Closing trading markets is not the main factor, but it is the most effective measure to control the epidemic to be at a low level. Consequently, periodically closing trading markets is proposed to prevent and control the spread of epidemic. [ABSTRACT FROM AUTHOR]