GLOBAL ASYMPTOTIC STABILITY FOR A DIFFUSION LOTKA-VOLTERRA COMPETITION SYSTEM WITH TIME DELAYS

Jia-Fang Zhang,Ping-An Zhang 대한수학회 2012 대한수학회보 Vol.49 No.6

A type of delayed Lotka-Volterra competition reaction-diffu\-sion system is considered. By constructing a new Lyapunov function, we prove that the unique positive steady-state solution is globally asymptotically stable when interspecies competition is weaker than intraspecies competition. Moreover, we show that the stability property does not depend on the diffusion coefficients and time delays.

Liver Cancer Mortality Characteristics and Trends in China from 1991 to 2012

Fang, Jia-Ying,Wu, Ku-Sheng,Zeng, Yang,Tang, Wen-Rui,Du, Pei-Ling,Xu, Zhen-Xi,Xu, Xiao-Ling,Luo, Jia-Yi,Lin, Kun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Purpose: To investigate the distribution of liver cancer mortality as well as its developing trend from 1991 to 2012, forecast the future five-year trend, and provide a basis for the comprehensive prevention and management. Materials and Methods: Mortality data for liver cancer in China from 1991 to 2012 were used to describe characteristics and distribution of liver cancer mortality. Trend surface analysis was used to study the geographical distribution of liver cancer mortality. Curve estimation, time series modeling, gray modeling (GM) and joinpoint regression were used to predict and forecast future trends. Results: The mortality rate of liver cancer has constantly increased in China since 1991. Rates in rural areas are higher than in urban areas, and in males are higher than in females. In addition, our data predicted that the trend will continue to increase in the next 5 years. The age-specific mortality of liver cancer increases with age and peaks in the group of 80-84 years old. Geographical analysis showed the liver mortality rate was higher in the southeast provinces, such as Jiangsu, Zhejiang and Guangdong, and southwest regions like Guangxi Province. Conclusions: The standardized mortality rate of liver cancer in China has consistently increased from 1991 to 2012, and the upward trend is predicted to continue in the future. Much better prevention and management of liver cancer is needed in high mortality areas (the southwestern and southeastern parts of China) and high mortality age groups (80- to 84-year-olds), especially in rural areas.

Genome-wide Analysis of Aberrant DNA Methylation for Identification of Potential Biomarkers in Colorectal Cancer Patients

Fang, Wei-Jia,Zheng, Yi,Wu, Li-Ming,Ke, Qing-Hong,Shen, Hong,Yuan, Ying,Zheng, Shu-Sen Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Background: Colorectal cancer is one of the leading causes of mortality worldwide. Genome wide analysis studies have identified sequence mutations causing loss-of-function that are associated with disease occurrence and severity. Epigenetic modifications, such DNA methylation, have also been implicated in many cancers but have yet to be examined in the East Asian population of colorectal cancer patients. Methods: Biopsies of tumors and matched non-cancerous tissue types were obtained and genomic DNA was isolated and subjected to the bisulphite conversion method for comparative DNA methylation analysis on the Illumina Infinium HumanMethylation27 BeadChip. Results: Totals of 258 and 74 genes were found to be hyper- and hypo-methylated as compared to the individual's matched control tissue. Interestingly, three genes that exhibited hypermethylation in their promoter regions, CMTM2, ECRG4, and SH3GL3, were shown to be significantly associated with colorectal cancer in previous studies. Using heatmap cluster analysis, eight hypermethylated and 10 hypomethylated genes were identified as significantly differentially methylated genes in the tumour tissues. Conclusions: Genome-wide methylation profiling facilitates rapid and simultaneous analysis of cancerous cells which may help to identify methylation markers with high sensitivity and specificity for diagnosis and prognosis. Our results show the promise of the microarray technology in identification of potential methylation biomarkers for colorectal cancers.

Optimization and simulation of the operational motion of a pantograph: Uplift and retraction

Fang Jia,Fengyu Xu,Hang Zhou,Defeng Zhang,Zhijie Xia 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.1

A single-arm pantograph of metro train was studied in this work. The mathematical model of a single-arm pantograph was first established and an optimal design method to obtain the geometric parameters of the pantograph was proposed. The 3D model for the pantograph was then built and the simulation was performed by using virtual prototyping technology to ensure superior performance of the optimized pantograph. The fatigue test of pantograph-insulator system was performed under two operating conditions: Electric pantograph lifting and real train operation. Fatigue test results validated the stability of the optimized pantograph system.

Fatigue properties of the pantograph–insulator system of metro trains: Experiments and the design for improvement

Fang Jia,Fengyu Xu,Zhijie Xia,Hang Zhou,Defeng Zhang 대한기계학회 2016 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.30 No.10

The power of a metro vehicle is supplied by the pantograph on the vehicle roof. During pantograph lifting, the insulator set of the pantograph is prone to fracture caused by the impact load. In this work, a Single-arm pantograph–insulator system (SPIS) of metro vehicles was studied for the fatigue fracture of the insulator set induced by impact load. The basic structure of the SPIS was first introduced. The dynamic axial force test and fatigue and fracture damage experiments was then conducted on SPIS for both simulation experiment platform and real vehicles to analyze the causes of the insulator fracture. A method to improve the design structure of the back-end insulator set was proposed to resolve the problems of both the impact failure of the insulator steel core and the stress concentration on the interface between a steel core and an epoxy resin. The finite element analysis results indicated that the improved insulator set shows a much smaller stress concentration. Therefore, the improved insulator set has a greatly reduced fatigue damage subjected to shear effect, which validated the feasibility of the improved structure design.

Effects of Different Medium Composition and Exogenous Hormones on Browning of Tree Peony (Paeonia suffruticosa Andr.) Callus in Tissue Cultu

Fang Fang Zhou,Zheng Wang,Li Yun Shi,Jia Jia Niu,Wen Qian Shang,Dan He,Song Lin He 한국화훼학회 2016 화훼연구 Vol.24 No.2

Browning is one of the key factors that influenced the callus subculture of tree peony (Paeonia suffruticosa Andr.). Effects of medium composition and exogenous hormones: macro elements of Murashige and Skoog (MS salts) and iron salt (Fe2+), pH, agar and 6-benzylaminopurine (6-BA), 1-naphthaleneacetic acid (NAA) and kinetin (KT) on the callus browning of P. suffruticosa ‘Shan Hu Tai’ in vitro were studied in this paper. Results showed that the browning of P. suffruticosa callus were more sensitive to KT than 6-BA in different concentrations of 6-BA and KT separately with different concentrations of NAA, and reduced to the lowest (13.3%) under 0.5 mg·L-1 NAA plus 0.3 mg·L-1 KT. 1/4 × MS plus 1/4 × Fe2+ was the best basic medium in which the browning rate was only 18.2%. The browning rate of the callus was the lowest of 4.0% under pH 6.5 and the callus grew better in 7.0 g·L-1 agar than others. This study indicated that the best medium preventing P. suffruticosa callus in vitro from browning was: 1/4 × MS medium supplemented with 6.95 mg·L-1Fe2+, 0.3 mg·L-1 KT, 0.5 mg·L-1 NAA, 6.0 g·L-1 agar and 30 g·L-1 sucrose in pH 6.5.

Characteristics and Prediction of Lung Cancer Mortality in China from 1991 to 2013

Fang, Jia-Ying,Dong, Hong-Li,Wu, Ku-Sheng,Du, Pei-Ling,Xu, Zhen-Xi,Lin, Kun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.14

Objective: To describe and analyze the epidemiological characteristics of lung cancer mortality in China from 1991 to 2013, forecast the future five-year trend and provide scientific evidence for prevention and management of lung cancer. Materials and Methods: Mortality data for lung cancer in China from 1991 to 2013 were used to describe epidemiological characteristics. Trend surface analysis was applied to analyze the geographical distribution of lung cancer. Four models, curve estimation, time series modeling, gray modeling (GM) and joinpoint regression, were performed to forecast the trend for the future. Results: Since 1991 the mortality rate of lung cancer increased yearly. The rate for males was higher than that for females and rates in urban areas were higher than in rural areas. In addition, our results showed that the trend will continue to increase in the ensuing 5 years. The mortality rate increased from age 45-50 and peaked in the group of 85 years old. Geographical analysis indicated that people living in northeast China provinces and the coastal provinces in eastern China had a higher mortality rate for lung cancer than those living in the centre or western Chinese provinces. Conclusions: The standardized mortality rate of lung cancer has constantly increased from 1991 to 2013, and been predicted to continue in the ensuing 5 years. Further efforts should be concentrated on education of the general public to increase prevention and early detection. Much better prevention and management is needed in high mortality areas (northeastern and eastern parts of China) and high risk populations (45-50-year-olds).

Colorectal Cancer Mortality Characteristics and Predictions in China, 1991-2011

Fang, Jia-Ying,Dong, Hong-Li,Sang, Xue-Jin,Xie, Bin,Wu, Ku-Sheng,Du, Pei-Ling,Xu, Zhen-Xi,Jia, Xiao-Yue,Lin, Kun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.17

Background: To identify the epidemiological characteristics of colorectal cancer mortality in China during the period of 1991-2011, and forecast the future five-year trend. Materials and Methods: Mortality data for colorectal cancer in China from 1991 to 2011 was used to describe epidemiological characteristics in terms of age group, gender, and rural/urban residence. Trend surface analysis was performed to analyze the geographical distribution of colorectal cancer. Four models including curve estimation, time series modeling, gray modeling and joinpoint regression were applied to forecast the trends for the future five years. Results: Since 1991 the colorectal cancer mortality rate increased yearly, and our results showed that the trend would continue to increase in the ensuing 5 years. The mortality rate in males was higher than that of females and the rate in urban areas was higher than in rural areas. The mortality rate was relatively low for individuals less than 60 years of age, but increased dramatically afterwards. People living in the northeastern China provinces or in eastern China had a higher mortality rate for colorectal cancer than those living in middle or western China provinces. Conclusions: The steadily increasing mortality of colorectal cancer in China will become a substantial public health burden in the foreseeable future. For this increasing trend to be controlled, further efforts should concentrate on educating the general public to increase prevention and early detection by screening. More effective prevention and management strategies are needed in higher mortality areas (Eastern parts of China) and high-risk populations (60+ years old).

Development of a Molecular Marker for Fruiting Body Pattern in Auricularia auricula-judae

( Fang-jie Yao ),( Li-xin Lu ),( Peng Wang ),( Ming Fang ),( You-min Zhang ),( Ying Chen ),( Wei-tong Zhang ),( Xiang-hui Kong ),( Jia Lu ),( Yoichi Honda ) 한국균학회 2018 Mycobiology Vol.46 No.1

The fruiting body pattern is an important agronomic trait of the edible fungus Auricularia auricula-judae, and an important breeding target. There are two types of fruiting body pattern: the cluster type and the chrysanthemum type. We identified the fruiting body pattern of 26 test strains, and then constructed two different near-isogenic pools. Then, we developed sequence characterized amplified region (SCAR) molecular markers associated with the fruiting body pattern based on sequence-related amplified polymorphism (SRAP) markers. Ten different bands (189-522 bp) were amplified using 153 pairs of SRAP primers. The SCAR marker “SCL-18” consisted of a single 522-bp band amplified from the cluster-type strains, but not the chrysanthemum strains. This SCAR marker was closely associated with the cluster- type fruiting body trait of A. auricula-judae. These results lay the foundation for further research to locate and clone genes controlling the fruiting body pattern of A. auricula-judae.

GLOBAL ASYMPTOTIC STABILITY FOR A DIFFUSION LOTKA-VOLTERRA COMPETITION SYSTEM WITH TIME DELAYS

Zhang, Jia-Fang,Zhang, Ping-An Korean Mathematical Society 2012 대한수학회보 Vol.49 No.6

A type of delayed Lotka-Volterra competition reaction-diffusion system is considered. By constructing a new Lyapunov function, we prove that the unique positive steady-state solution is globally asymptotically stable when interspecies competition is weaker than intraspecies competition. Moreover, we show that the stability property does not depend on the diffusion coefficients and time delays.