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FORCED OSCILLATIONS OF A CLASS OF NONLINEAR DISPERSIVE WAVE EQUATIONS AND THEIR STABILITY

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Journal of Systems Science & Complexity 2007年第2期20卷 284-292页

作者： Muhammad USMAN bingyu zhang Department of Mathematical Sciences University of Cincinnati Cincinnati Ohio 45221-0025 USA

It has been observed in laboratory experiments that when nonlinear dispersive waves are forced periodically from one end of undisturbed stretch of the medium of propagation, the signal eventually becomes temporally periodic at each spatial point. The observation has been confirmed mathematically in the context of the damped Korteweg-de Vries （KdV） equation and the damped Benjamin-Bona-Mahony （BBM） equation. In this paper we intend to show the same results hold for the pure KdV equation （without the damping terms） posed on a finite domain. Consideration is given to the initial-boundary-value problem {ut＋ux＋uux＋uxxx=0, u（x,0）=φ（x）, 0〈x〈1, t〉0,u（0,t）=h（t）, u（1,t） = 0, ux（1,t） = 0, t〉*** is shown that if the boundary forcing h is periodic with small ampitude, then the small amplitude solution u of （＊） becomes eventually time-periodic. Viewing （＊）（without the initial condition） as an infinite-dimensional dynamical system in the Hilbert space L^2（0, 1）, we also demonstrate that for a given periodic boundary forcing with small amplitude, the system （＊） admits a （locally） unique limit cycle, or forced oscillation, which is locally exponentially stable. A list of open problems are included for the interested readers to conduct further investigations.

关键词： Forced oscillation stability the BBM equation the KdV equation time-periodic solution

Waterlogging tolerance and wood properties of transgenic Populus alba×glandulosa expressing Vitreoscilla hemoglobin gene(Vgb)

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Journal of Forestry Research 2021年第2期32卷 831-839页

作者： Yiliang Li Weixi zhang Wenxu Zhu bingyu zhang Qinjun Huang Xiaohua Su State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091People’s Republic of China Key Laboratory of Tree Breeding and Cultivation National Forestry and Grassland AdministrationBeijing 100091People’s Republic of China Guangdong Provincial Key Laboratory of Silviculture Protection and UtilizationGuangzhou 510520People’s Republic of China Guangdong Academy of Forestry Guangzhou 510520People’s Republic of China College of Forestry Shenyang Agricultural University120 Dongling StreetShengyang 110866People’s Republic of China

Because overexpression of Vitreoscilla hemoglobin gene(Vgb)gene in plants can enhance tolerance to waterlogging,here Vgb was inserted into Populus alba×glandulosa to investigate its expression and effects on growth and physiological responses to waterlogging stress in the transgenic *** blotting and RT-PCR analysis of Vgb-transgenic ***×glandulosa showed that the Vgb gene was integrated into the genome of the V13-81 and V13-85 transgenic lines and *** greenhouse waterlogging stress tests,mortality of the transgenic poplar was significant lower than that of nontransgenic plants with increasing treatment time from 2 to 22 *** transgenic plants had higher chlorophyll content and less chloroplast damage than in the control ***,starch accumulation increased,and growth was enhanced in the transgenic plants,suggesting that the Vgb-expressing lines had improved energy *** trials of the transgenic poplar suggested that Vgb expression promotes growth and influences wood *** together,our results suggest that the expression of Vgb can increase the accumulation of chlorophyll and starch in the transgenic poplar,improve its ability to endure flooding,and improve growth and wood quality of the transgenic plants.

关键词： Populus alba×glandulosa vgb gene Waterlogging stress Growth Microscopy

高职课程思政之微电影教学方法探索与实践研究——以“通信概论”课程思政为例

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科教文汇 2024年第8期 68-71页

作者：李莉郑玉红张冰玉张静石家庄邮电职业技术学院河北石家庄050021

微电影教学方法遵循理论与实践相结合、教师引领与学生践行相统一、思政语言指导与学生网络语言拍摄相融合的原则,是一种适应高职学生学习行为的新模式,为课程思政教学方法创新提供了路径。该文以“通信概论”课程思政教学实践为例,探... 详细信息

微电影教学方法遵循理论与实践相结合、教师引领与学生践行相统一、思政语言指导与学生网络语言拍摄相融合的原则,是一种适应高职学生学习行为的新模式,为课程思政教学方法创新提供了路径。该文以“通信概论”课程思政教学实践为例,探索和构建了以“建好一个团队、抓好“两结合”、做好“三环节”、打造‘四有’沟通方法、完善五类促进措施”为内容的“12345”微电影教学模式,使高职专业课程思政与微电影相容相吸。提出了优化“两感双能”教学评价量化指标,实现了课程思政考核创新,并结合课程思政教学实践给出了深化微电影教学模式改革、提升育人实效的对策。

关键词：微电影教学方法高职教育课程思政

入院时血清HDL-C和三酰甘油-葡萄糖指数与非糖尿病急性心肌梗死患者冠状动脉病变严重程度、短期预后的关系

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实用心脑肺血管病杂志 2024年第8期32卷 32-36页

作者：王玮王永张丙雨湛长青安徽省芜湖市第二人民医院心血管内科 241000

目的探究入院时血清HDL-C和三酰甘油-葡萄糖(TyG)指数与非糖尿病急性心肌梗死(AMI)患者冠状动脉病变严重程度、短期预后的关系。方法回顾性选取2019—2022年芜湖市第二人民医院收治的非糖尿病AMI患者104例。收集患者的临床资料,采用Gens... 详细信息

目的探究入院时血清HDL-C和三酰甘油-葡萄糖(TyG)指数与非糖尿病急性心肌梗死(AMI)患者冠状动脉病变严重程度、短期预后的关系。方法回顾性选取2019—2022年芜湖市第二人民医院收治的非糖尿病AMI患者104例。收集患者的临床资料,采用Gensini积分评估患者冠状动脉病变严重程度,根据冠状动脉病变严重程度将患者分为轻度组(n=33)、中度组(n=54)、重度组(n=17)。记录患者术后半年主要不良心血管事件(MACE)发生情况,根据MACE发生情况将患者分为预后不良组(发生MACE,n=31)和预后良好组(未发生MACE,n=73)。非糖尿病AMI患者短期预后不良的影响因素分析采用多因素Logistic回归分析,采用ROC曲线分析入院时血清HDL-C、TyG指数及二者联合对非糖尿病AMI患者短期预后不良的预测价值。结果中度组患者入院时血清HDL-C低于轻度组,入院时TyG指数高于轻度组(P<0.05);重度组患者入院时HDL-C低于轻度组和中度组,入院时TyG指数高于轻度组和中度组(P<0.05)。预后不良组患者年龄大于预后良好组,合并高血压、合并高脂血症、合并外周动脉疾病、有卒中史、Killip分级Ⅲ~Ⅳ级、冠状动脉多支病变者占比及入院时空腹血糖(FPG)、血清TG、血清LDL-C、TyG指数高于预后良好组,入院时心率、左心室射血分数(LVEF)、血清HDL-C低于预后良好组(P<0.05)。多因素Logistic回归分析结果显示,Killip分级Ⅲ~Ⅳ级、冠状动脉多支病变、入院时TyG指数升高是非糖尿病AMI患者短期预后不良的危险因素,血清HDL-C升高是其保护因素(P<0.05)。ROC曲线分析结果显示,入院时血清HDL-C、TyG指数及二者联合预测非糖尿病AMI患者短期预后不良的AUC分别为0.781〔95%CI(0.676~0.885)〕、0.797〔95%CI(0.701~0.893)〕、0.882〔95%CI(0.810~0.954)〕。结论入院时血清HDL-C、TyG指数与非糖尿病AMI患者冠状动脉病变严重程度相关;入院时血清HDL-C升高是非糖尿病AMI患者短期预后不良的保护因素,入院时TyG指数升高是其危险因素,入院时血清HDL-C、TyG指数对非糖尿病AMI患者短期预后不良有一定预测价值,且二者联合的预测价值较高。

关键词：心肌梗死胆固醇,HDL 三酰甘油-葡萄糖指数预后

NONHOMOGENEOUS BOUNDARY VALUE PROBLEMS FOR THE KORTEWEG-DE VRIES EQUATION ON A BOUNDED DOMAIN

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Journal of Systems Science & Complexity 2010年第3期23卷 499-526页

作者： Eugene F. KRAMER bingyu zhang Department of Mathematics Physics and Computer Science University of Cincinnati Raymond Walters College Cincinnati Ohio 45236 USA Department of Mathematical Sciences University of Cincinnati Cincinnati Ohio 45221 USA

This paper studies an initial-boundary-value problem (IBVP) of the Korteweg-de Vriesequation posed on a finite interval with general nonhomogeneous boundary *** thestrong Kato smoothing property of the associated linear problem,the IBVP is shown to be locallywell-posed in the space H^s(0,1) for any s≥0 via the contraction mapping principle.

关键词： KdV equation Korteweg-de Vries equation well-posed.

A cDNA microarray analysis of the molecular control of poplar wood properties

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Journal of Forestry Research 2017年第1期28卷 71-82页

作者： Qinjun Huang Changjun Ding Weixi zhang bingyu zhang Yanguang Chu Dahai Wang Xiaohua Su State Key Laboratory of Tree Genetics and Breeding Research Institute of ForestryChinese Academy of ForestryBeijing 100091China Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Beijing 100091China

Molecular biological research into wood development and formation has been the focus in recent years, but the pace of discovery of related genes and their functions in the control of wood properties has been slow. The microarray technique--with its advantages of high throughput capacity, sensitivity, and reliability over other tools developed for investigating genes expression patterns-is capable of rapidly assaying thousands of genes. In this study, a cDNA microarray prepared from two cDNA libraries of developing poplar xylem tissues was used to assay gene expression patterns in immature xylem tissues at different heights from the main stem of Populus deltoides （15 years old）, which was confirmed to have distinct wood properties （microfibrillar angle, woody density） by X-ray. Two hundred seventy-four transcripts with differ- ential expression profles between the chips were screened out, and the individual clones were subjected to 5＇ sequencing. Using bioinformatic analysis, we identified candidate genes that may influence poplar wood properties, many of which belong to various regulatory and signal transduction gene families, such as zinc finger protein transcription factor, DNA-binding transcription factor, ethylene response factors, and so on. The results suggest that these genes may regulate enzymes involved in wood formation. Further work will be performed to clone these genes and determine how they influence poplar wood properties.

关键词： Populus deltoides cDNA microarray Expression profile Wood density Microfibfillar angle

Assessing bacterial communities in the rhizosphere of 8-year-old genetically modified poplar(Populus spp.)

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Journal of Forestry Research 2016年第4期27卷 939-947页

作者： Wenxu Zhu Yanguang Chu Changjun Ding Qinjun Huang bingyu zhang Weixi zhang Xiaohua Su State Key Laboratory of Tree Genetics and Breeding Research Institute of Forestry Chinese Academy of ForestryBeijing 100091 China Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration Beijing 100091 China

Microbe communities in rhizosphere ecosystems are important for plant health but there is limited knowledge of them in the rhizospheres of genetically modified（GM） plants, especial for tree species. We used the amplitude sequencing method to analyze the V4 regions of the 16 S r RNA gene to identify changes in bacterial diversity and community structure in two GM lines（D520 and D521）, one non-genetically modified（nonGM） line and in uncultivated soil. After chimera filtering,468.133 sequences in the domain Bacteria remained. There were ten dominant taxonomic groups（with [1 % of all sequences） across the samples. 241 of 551 genera（representing a ratio of 97.33 %） were common to all samples.A Venn diagram showed that 1.926 operational taxonomic units（OTUs） were shared by all samples. We found a specific change, a reduction in Chloroflexi, in the microorganisms in the rhizosphere soil planted with poplars. Taken together, the results showed few statistical differences in the bacterial diversity and community structure between the GM line and non-GM line, this suggests that there was no or very limited impact of this genetic modification on the bacterial communities in the rhizosphere.

关键词： rhizosphere communities Bacteria sequencing poplar planted taxonomic representing genera microbial

Fluorescence Detection for H_2PO_4^- based on Carbon Dots/Fe^(3＋) Composite

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Journal of Wuhan University of Technology(Materials Science) 2016年第6期31卷 1226-1229页

作者：范小春 zhang bingyu 丁莉芸 XU Chuang HUANG Jun School of Civil Engineering and Architecture Wuhan University of Technology Wuhan 430070 China National Engineering Laboratory for Fiber Optic Sensing Technology Wuhan University of Technology Wuhan 430070 China

A novel fluorescent probe for H_2PO_4^- was designed and fabricated based on the carbon dots/Fe^（3＋） composite. The carbon dots were synthesized by an established one-pot hydrothermal method and characterized by transmission electron microscope, X-ray diffractometer, UV-Vis absorption spectrometer and fluorescence spectrophotometer. The carbon dots/Fe^（3＋） composite was obtained by aqueous mixing of carbon dots and FeCl_3, and its fluorescence property was characterized by fluorescence spectrophotometer. The fluorescence of carbon dots was quenched by aqueous Fe^（3＋） cations, resulting in the low fluorescence intensity of the carbon dots/Fe^（3＋） composite. On the other hand, H_2PO_4^- reduced the concentration of Fe^（3＋） by chemical reaction and enhanced the fluorescence of the carbon dots/Fe^（3＋） composite. The Stern-Volmer equation was introduced to describe the relation between the relative fluorescence intensity of the carbon dots/Fe^（3＋） composite and the concentration of H_2PO_4^-, and a fine linearity（R2=0.997） was found in the range of H_2PO_4^- concentration of 0.4-12 m M.

关键词： H2PO4-detection fluorescence carbon dots/Fe3+ composite

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联合图像配准的脑卒中病灶自动分割方法研究

重庆邮电大学学报（自然科学版） 2024年第4期36卷 729-737页

作者：李欣蔚许炜鑫陈勇秦对张冰玉李章勇王伟重庆邮电大学生物医学工程研究中心重庆400065 陆军军医大学第一附属医院医学工程科重庆400038

针对目前慢性脑卒中的病灶分割准确性相对较低的问题,提出了一种联合深度图像配准的慢性脑卒中自动分割方法。采用深度拉普拉斯金字塔图像配准网络,在微分同胚映射的空间内以从粗到细的方式获得大脑分区,以得到病灶位置的解剖先验信息;... 详细信息

针对目前慢性脑卒中的病灶分割准确性相对较低的问题,提出了一种联合深度图像配准的慢性脑卒中自动分割方法。采用深度拉普拉斯金字塔图像配准网络,在微分同胚映射的空间内以从粗到细的方式获得大脑分区,以得到病灶位置的解剖先验信息;将原始磁共振图像和配准阶段的分区结果联合,输入到加入了通道和空间注意力模块的U-Net进行病灶分割。在公开的数据集ATLAS上进行测试表明,提出的方法有效提高了慢性脑卒中病灶分割的准确性,比经典的2D U-Net提升了4.4百分点,证明了基于深度图像配准的大脑分区先验可有效增强模型对病灶的分割性能,更好的组织分割能提高病灶分割准确性。

关键词：慢性脑卒中图像配准病灶分割