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The Same Distribution of Limit Cycles in a Hamiltonian System with Nine Seven-order Perturbed Terms

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Acta Mathematicae Applicatae Sinica 2008年第1期24卷 167-176页

作者： tao Jiang zhi-yan Yang School of Information Beijing Wuzi University Beijing 101149 China

Using qualitative analysis and numerical simulation, we investigate the number and distribution of limit cycles for a cubic Hamiltonian system with nine different seven-order perturbed terms. It is showed that these perturbed systems have the same distribution of limit cycles. Furthermore, these systems have 13, 11 and 9 limit cycles for some parameters, respectively. The accurate positions of the 13, 11 and 9 limit cycles are obtained by numerical exploration, respectively. Our results imply that these perturbed systems are equivalent in the sense of distribution of limit cycles. This is useful for studying limit cycles of perturbed systems.

关键词： Limit cycles bifurcation

Effect of lactic acid bacteria and propionic acid on conservation characteristics,aerobic stability and in vitro gas production kinetics and digestibility of whole-crop corn based total mixed ration silage

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Journal of Integrative Agriculture 2017年第7期16卷 1592-1600页

作者： CHEN Lei YUAN Xian-jun LI Jun-feng WANG Si-ran DONG zhi-hao Shao tao Institute of Ensiling and Processing of Grass Nanjing Agricultural UniversityNanjing 210095P.R.China

This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aer- obic stability and in vitro gas production kinetics and digestibility of whole-crop corn based totalmixed ration （TMR） silage. Total mixed ration was ensiled with four treatments：（1） no additives （control）; （2） an inoculant （Lactobacillus plantarum）（L）; （3） propionicacid （P）; （4） propionic acid＋lactic acid bacteria （PL）. All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH （〈3.80） and ammonia nitrogen （NH3-N） contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH3-N contents of TMR silage compared to the control （P〈0.05）. After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly （P〈0.05） increased them. L silage had higher （P〈0.05） in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid prod

关键词： lactic acid bacteria propionic acid fermentation quality aerobic stability in vitro digestibility total mixed rationsilage

Bifurcations and Chaos in Mira 2 Map

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Acta Mathematicae Applicatae Sinica 2017年第4期33卷 967-978页

作者： tao JIANG zhi-yan YANG School of Information Beijing Wuzi University Beijing 101149 China

In this paper, Mira 2 map is investigated. The conditions of the existence for fold bifurcation, flip bifurcation and Naimark-Sacker bifurcation are derived by using center manifold theorem and bifurcation theory. And the conditions of the existence for chaos in the sense of Marroto are obtained. Numerical simulation results not only show the consistence with the theoretical analysis but also display complex dynamical behaviors, including period-n orbits, crisis, some chaotic attractors, period-doubling bifurcation to chaos, quasi-period behaviors to chaos, chaos to quasi-period behaviors, bubble and onset of chaos.

关键词： Mira 2 map fold bifurcation flip bifurcation Naimark-Sacker bifurcation chaos in the sense ofMarroto

Wavelets with Differential Relation

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Acta Mathematica Sinica,English Series 2011年第5期27卷 1011-1022页

作者： zhi-tao CHUANG Youming LIU Department of Applied Mathematics Beijing University of Technology Beijing 100124 P. R. China

Divergence-free wavelets are successfully applied to numerical solutions of Navier-Stokes equation and to analysis of incompressible flows. They closely depend on a pair of one-dimensional wavelets with some differential relations. In this paper, we point out some restrictions of those wavelets and study scaling functions with the differential relation; Wavelets and their duals are discussed; In addition to the differential relation, we are particularly interested in a class of examples with the interpolatory property; It turns out there is a connection between our examples and Micchelli＇s work.

关键词： Differential relation interpolation wavelets scaling functions symmetry

Conversion of the Statistical Combining Ability into a Genetic Concept

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Journal of Integrative Agriculture 2012年第1期11卷 43-52页

作者： LV Ai-zhi ZHANG hao ZHANG Zu-xin tao Yong-sheng YUE Bing ZHENG Yong-lian College of Agronomy Hebei Agricultural University/Hebei Sub-Center of National Maize Improvement Center Baoding 071001 P.R. China National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University Wuhan 430070 P.R. China

Since the combining ability was proposed in 1942, efforts to uncover the genetic basis underlying this phenomenon have been ongoing for nearly 70 yr, with little success. Some breeding strategies based on evaluation of combining ability have been produced, and are still extensively used in hybrid breeding. In this review, the genetic basis underlying these breeding strategies is discussed, and a potential genetic control of general combining ability （GCA） is postulated. We suggested that GCA and the yields of inbred lines might be genetically controlled by different sets of loci on the maize genome that are transmitted into offspring. Different inbred lines might possess different favorable alleles for GCA. In hybrids, loci involved in multiple pathways, which are directly or indirectly associated with yield performance, might be regulated by GCA loci. In addition, a case of GCA mapping using a set of testcross progeny from introgression lines is provided.

关键词： general combining ability (GCA) testcross GCA mapping quantitative trait locus (QTL) maize (Zea mays L.),introgression line

Effect of thermal cycles on microstructure of reduced activation steel fabricated using laser melting deposition

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Journal of Iron and Steel Research International 2021年第3期28卷 316-326页

作者： Qian An zhi-xin Xia Chi Zhang zhi-gang Yang hao Chen School of Material Science and Engineering Tsinghua UniversityBeijing100084China Shagang School of Iron and Steel Soochow UniversitySuzhou215021JiangsuChina

Reduced activation steel was successfully fabricated by laser melting deposition employing a Gaussian and a ring-shaped *** microstructure evolution of the reduced activation steel was investigated using the scanning electron microscope,transmission electron microscope and electron backscatter *** experimental results showed that the grains close to the substrate were smaller than the grains in the upper *** to those deposited using a Gaussian laser,the samples deposited using a ring-shaped laser showed a more homogeneous ***,a finite element analysis(FEA)model was applied to reveal the thermal history during laser melting *** simulation results were well validated with the experimental *** results indicate that the peak temperature increases and the cooling rate decreases,as the layer gets further from the ***,the temperature and the cooling rate resulting from the Gaussian laser model were higher at the midline of the samples and lower around the edges,whereas those of the ring-shaped laser model were consistent with both at the center and around the edges.

关键词： Laser melting deposition Reduced activation steel Microstructure evolution Thermal cycle Finite element analysis

Association of genetic polymorphisms of aldehyde dehydrogenase-2 with esophageal squamous cell dysplasia

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World Journal of Gastroenterology 2010年第27期16卷 3445-3449页

作者： Ying-zhi Zhou Yu-tao Diao hao Li Hui-Qing Li Qing Ma Jia Cui School of Economics Shandong University 27# Shanda Nanlu Jinan 250100 Shandong Province China Department of Epidemiology and Health Statistics School of Public Health 44# Wenhuaxi Road Jinan 250012 China Tumor Center Qilu Hospital of Shandong University107# Wenhuaxi RoadJinan 250012Shandong ProvinceChina Department of Epidemiology Institute of Basic MedicineShandong Academy of Medical Sciences18877# Jingshi RoadJinan 250062Shandong ProvinceChina

AIM:To demonstrate the possible associations between genetic polymorphisms of aldehyde dehydrogenase-2(ALDH2) and esophageal squamous cell dysplasia(ESCD).METHODS:All participants came from an area of high incidence of esophageal cancer and underwent an endoscopic staining examination;biopsies were taken from a non-staining area of the mucosa and diagnosed by *** on the examinations,the subjects were divided into the control group with normal esophageal squamous epithelial cells and the ESCD ***2 genotypes of 396 cases were determined including 184 ESCD cases and 212 *** odds ratio(OR) and 95% confidence intervals(95% CI) were calculated by binary logistic regression ***:The distribution of ALDH2 genotypes showed significant differences between the two *** adjustment factors were gender and age in the logistic regression *** with 2*2/2*2 genotype,2*1/2*1 genotype was found to be a risk factor for ESCD,and the OR(95% CI) was 4.50(2.21-9.19).There were significant correlations between ALDH2 genotypes and alcohol drinking/smoking/history of esophageal ***:The ALDH2 polymorphism is significantly associated with ESCD.

关键词： Aldehyde dehydrogenase 2 Polymorphism Alcohol Smoking Esophageal squamous cell dysplasia History of esophageal cancer

Tau hyperphosphorylation induces apoptotic escape and triggers neurodegeneration in Alzheimer's disease

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Neuroscience Bulletin 2014年第2期30卷 359-366页

作者： Jian-zhi Wang zhi-hao Wang Qing Tian Department of Pathology and Pathophysiology Key Laboratory of Ministry of Education of China for Neurological DisordersTongji Medical College Huazhong University of Science and Technology

Since abnormal post-translational modifications or gene mutations of tau have been detected in over twenty neurodegenerative disorders, tau has attracted widespread interest as a target protein. Among its various post-translational modifications, phosphorylation is the most extensively studied. It is recognized that tau hyperphosphorylation is the root cause of neurodegeneration in Alzheimer＇s disease （AD）; however, it is not clear how it causes neurodegeneration. Based on the findings that tau hyperphosphorylation leads to the escape of neurons from acute apoptosis and simultaneously impairs the function of neurons, we have proposed that the nature of AD neurodegeneration is the consequence of aborted apoptosis induced by tau phosphorylation. Therefore, proper manipulation of tau hyperphosphorylation could be promising for arresting AD neurodegeneration. In this review, the neuroprotective and neurodegenerative effects of tau hyperphosphorylation and our thoughts regarding their relationship are presented.

关键词： Alzheimer's disease microtubule-associated protein tau hyperphosphorylaUon apoptosis neurodegeneration

不同禾本科植物对矿区重金属污染土壤的修复效果研究

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陕西科技大学学报 2025年第1期43卷 23-28页

作者：贾红磊安昊东王晴李成涛陕西科技大学环境科学与工程学院陕西西安710021

以秦岭腹地凤县典型铅锌尾矿区周边的农田土壤为研究对象,采用黑麦草、剪股颖、百慕大草三种类型的草本植物进行室内盆栽实验,阐述了干旱胁迫对植物生长的影响,探究不同禾本科植物在干旱半干旱地区对重金属污染土壤的修复效果,以期筛选... 详细信息

以秦岭腹地凤县典型铅锌尾矿区周边的农田土壤为研究对象,采用黑麦草、剪股颖、百慕大草三种类型的草本植物进行室内盆栽实验,阐述了干旱胁迫对植物生长的影响,探究不同禾本科植物在干旱半干旱地区对重金属污染土壤的修复效果,以期筛选出能够适合在金属矿区修复中种植的耐旱性草本植物.结果表明:相比剪股颖和百慕大草,黑麦草在该土壤条件下能够具有较高的生物量累积,且在干旱条件下生物量降低的较少(P<0.05),黑麦草的丙二醛(MDA)含量与电导率(EC)较低,说明其具有较好的耐旱能力和较高的重金属耐受能力(P<0.05).在重金属污染土壤修复中,黑麦草中Cd、Pb和Zn的含量最高,且对Cd的富集系数可达到0.98,种植黑麦草对土壤中Cd的去除效率高达50%以上,Pb的去除效率为15.5%.因此,研究认为黑麦草对于凤县矿区Pb、Zn和Cd污染土壤具有更好的修复潜力.

关键词：重金属干旱土壤修复植物筛选

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