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Nanohydroxyapatite and liposomes-coated integral bilayer scaffold for osteochondral repair via mimicking the dual differentiation microenvironment of BMSCs
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作者 Weikang Zhao Biemin Sun +10 位作者 Yu Song Yuan Cao Yichen liu Dandan Zhou Qiang Zhou Feng Xie Wei Huang Xiaoxiao li yuling li Yanqin Xu Yiyang Wang 《Nano Materials Science》 2025年第4期539-554,共16页
Osteochondral defects pose an enormous challenge,and no satisfactory therapy is available to date due to the hierarchy of the native tissue consisting of articular cartilage and subchondral bone.Constructing a scaffol... Osteochondral defects pose an enormous challenge,and no satisfactory therapy is available to date due to the hierarchy of the native tissue consisting of articular cartilage and subchondral bone.Constructing a scaffold with biological function and biomimetic structure is the key to achieving a high-quality repair effect.Herein,a natural polymer-based bilayer scaffold with a porous architecture similar to that of osteochondral tissue is designed,involving the transforming growth factor-beta3-liposome-loaded upper layer for superficial cartilage regeneration and the nanohydroxyapatite-coated lower layer for subchondral bone rehabilitation.This research is conducted to evaluate the effects of nanoparticle-modified bilayer scaffold to mimic the hierarchical pro-chondrogenic and proosteogenic microenvironment for the recruited endogenous bone marrow mesenchymal stem cells.The fabricated composites were evaluated for mechanical,physicochemical,biological properties,in vitro and in vivo tissue regeneration potential.Overall,the current bilayer scaffold could regenerate a cartilage-bone integrated tissue with a seamless interfacial integration and exhibited superior tissue repair outcomes compared to other single layer scaffolds based on morphological,radiological and histological evaluation,verifying that this novel graft could be an effective approach to tissue-engineered analogs of cartilage-subchondral bone and offer new therapeutic opportunities for osteochondral defect-associated diseases. 展开更多
关键词 Nanohydroxyapatite LIPOSOME Bilayer scaffold Osteochondral repair
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Insights into the interplay between gut microbiota and lipid metabolism in the obesity management of canines and felines 被引量:2
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作者 Kaiqi li Xiangyu Xiao +8 位作者 yuling li Sichen Lu Jianghang Zi Xiaoqiang Sun Jia Xu Hao‑Yu liu Xiaoqiong li Tongxing Song Demin Cai 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1761-1777,共17页
Obesity is a prevalent chronic disease that has significant negative impacts on humans and our companion animals,including dogs and cats.Obesity occurs with multiple comorbidities,such as diabetes,hypertension,heart d... Obesity is a prevalent chronic disease that has significant negative impacts on humans and our companion animals,including dogs and cats.Obesity occurs with multiple comorbidities,such as diabetes,hypertension,heart disease and osteoarthritis in dogs and cats.A direct link between lipid metabolism dysregulation and obesity-associated diseases has been implicated.However,the understanding of such pathophysiology in companion animals is lim-ited.This review aims to address the role of lipid metabolism in various metabolic disorders associated with obesity,emphasizing the involvement of the gut microbiota.Furthermore,we also discuss the management of obesity,including approaches like nutritional interventions,thus providing novel insights into obesity prevention and treatment for canines and felines. 展开更多
关键词 CAT DOG Gut microbiota Lipid metabolism Obesity Management
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A green cross-linking method for the preparation of renewable threedimensional graphene sponges for efficient adsorption of Congo red dye 被引量:1
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作者 Zhuang liu Bo Gao +3 位作者 Haoyuan Han yuling li Haiyang Fu Donghui Wei 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期84-93,共10页
Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn pollutants.However,their utilization is hindered by high prepar... Graphene-based materials possess significant potential for the treatment of dye wastewater due to their exceptional adsorption properties toward stubborn pollutants.However,their utilization is hindered by high preparation costs,low yields,environmental pollution during synthesis,and challenges in regenerating the adsorbent.This study proposes a novel approach to address these limitations by developing nitrogen-doped three-dimensional(3D)polyvinyl alcohol(PVA)crosslinked graphene sponges(N-PGA)using a cross-linking method with ammonium carbonate.This method offers a relatively mild,environmentally friendly approach.Ammonium carbonate serves as both a reducing and modifying agent,facilitating the formation of the intrinsic structure of N-PGA and acting as a nitrogen source.Meanwhile,PVA is utilized as the cross-linking agent.The results demonstrate that N-PGA exhibits a favorable internal 3D hierarchical porous structure and possesses robust mechanical properties.The measured specific surface area(BET)of N-PGA was as high as406.538 m^(2)·g^(-1),which was favorable for its efficient adsorption of Congo red(CR)dye molecules.At an initial concentration of 50 mg·L^(-1),N-PGA achieved an impressive removal rate of 89.6%and an adsorption capacity of 112 mg·g^(-1)for CR dye.Furthermore,it retained 79%of its initial adsorption capacity after 10 cycles,demonstrating excellent regeneration performance.In summary,the synthesized N-PGA displays remarkable efficacy in the adsorption of CR dye in wastewater,opening up new possibilities for utilizing 3D porous graphene nanomaterials as efficient adsorbents in wastewater treatment. 展开更多
关键词 Green chemistry Graphene sponge Adsorbents ADSORPTION Congo red Regeneration
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The cytosolic isoform of triosephosphate isomerase,ZmTPI4,is required for kernel development and starch synthesis in maize(Zea mays L.)
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作者 Wenyu li Han Wang +7 位作者 Qiuyue Xu Long Zhang Yan Wang Yongbiao Yu Xiangkun Guo Zhiwei Zhang Yongbin Dong yuling li 《The Crop Journal》 SCIE CSCD 2024年第2期401-410,共10页
Triosephosphate isomerase(TPI)is an enzyme that functions in plant energy production,accumulation,and conversion.To understand its function in maize,we characterized a maize TPI mutant,zmtpi4.In comparison to the wild... Triosephosphate isomerase(TPI)is an enzyme that functions in plant energy production,accumulation,and conversion.To understand its function in maize,we characterized a maize TPI mutant,zmtpi4.In comparison to the wild type,zmtpi4 mutants showed altered ear development,reduced kernel weight and starch content,modified starch granule morphology,and altered amylose and amylopectin content.Protein,ATP,and pyruvate contents were reduced,indicating ZmTPI4 was involved in glycolysis.Although subcellular localization confirmed ZmTPI4 as a cytosolic rather than a plastid isoform of TPI,the zmtpi4 mutant showed reduced leaf size and chlorophyll content.Overexpression of ZmTPI4 in Arabidopsis led to enlarged leaves and increased seed weight,suggesting a positive regulatory role of ZmTPI4 in kernel weight and starch content.We conclude that ZmTPI4 functions in maize kernel development,starch synthesis,glycolysis,and photosynthesis. 展开更多
关键词 MAIZE Kernel STARCH Weight PHOTOSYNTHESIS
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ZmZFP2 encoding a C4HC3-type RING zinc finger protein regulates kernel size and weight in maize
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作者 Long Zhang Qilei Wang +12 位作者 Wenyu li Qi Zheng Miaomiao Fu Han Wang Xinyu li Yan Wang lingwei Hu Weigang Yao lifeng Wang Huiyong li Yongbin Dong Yongrui Wu yuling li 《The Crop Journal》 2025年第2期418-431,共14页
The development of maize(Zea mays)kernels is a complex physiological process regulated by numerous genes in a spatially and temporally coordinated manner.However,many regulatory genes involved in this process remain u... The development of maize(Zea mays)kernels is a complex physiological process regulated by numerous genes in a spatially and temporally coordinated manner.However,many regulatory genes involved in this process remain unidentified.In this study,we identified ZmZFP2,a gene encoding a C4HC3-type RING zinc finger protein,which regulates kernel size and weight.This discovery was based on suppression subtractive hybridization from maize endosperm in our previous research.We further investigated the role of ZmZFP2 in regulating kernel development.The zmzfp2-ems mutant exhibited significantly reduced kernel size and weight,accompanied by fewer endosperm cells and altered starch and protein accumulation.CRISPR/Cas9-mediated knockouts and overexpression lines confirmed that ZmZFP2 positively regulates kernel size and weight,with overexpression leading to increased kernel size and weight.Transcriptome analysis revealed that ZmZFP2 regulates genes involved in zeatin biosynthesis,starch metabolism,and protein processing,further supporting its role in kernel development.Additionally,ZmZFP2 was shown to interact with the transcription factor ZmEREB98,implicating it in the gene regulatory network during grain filling.Together,these findings demonstrate that ZmZFP2 is a key regulator of maize kernel size and weight,functioning through its E3 ubiquitin ligase activity and interactions with various metabolic pathways.This study provides novel insights into the genetic regulation of kernel development and presents potential strategies for improving maize yield and quality. 展开更多
关键词 MAIZE Kernel weight and size Starch and protein accumulation E3 ubiquitin ligase Transcriptome analysis
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将理论和实践深度融合的研究性教学模式全过程探索——以“白醋总酸含量的测定”自主设计方案为例
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作者 王利平 王焕锋 +5 位作者 李玉玲 李领川 李晓静 陈会锋 姬博文 王琳娜 《大学化学》 2025年第5期244-251,共8页
借助研究手段,将理论与实践课程内容深度融合,对我校大学一年级学生的分析化学课程进行了多维度研究性教学模式改革。此模式有效提升了学生的主动学习能力,培养了他们处理信息和解决实际问题能力,促进了从浅层学习向深度学习的转变。希... 借助研究手段,将理论与实践课程内容深度融合,对我校大学一年级学生的分析化学课程进行了多维度研究性教学模式改革。此模式有效提升了学生的主动学习能力,培养了他们处理信息和解决实际问题能力,促进了从浅层学习向深度学习的转变。希望为化学基础知识不系统,研究能力薄弱的低年级学生进行研究性教学提供些许参考。 展开更多
关键词 研究性教学 深度学习 课堂改革
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Abnormal Brain Structure and Function in First-Episode Childhood- and Adolescence-Onset Schizophrenia: Association with Clinical Symptoms 被引量:5
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作者 Yanhong Xia Dan Lv +9 位作者 Yinghui liang Haisan Zhang Keyang Pei Rongrong Shao Yali li Yan Zhang yuling li Jinghua Guo Luxian Lv Suqin Guo 《Neuroscience Bulletin》 SCIE CAS CSCD 2019年第3期522-526,共5页
Dear Editor,Schizophrenia is one of the most complicated and serious psychiatric disorders, and patients often show markedly disrupted structural and functional abnormalities during resting-state imaging scans of the ... Dear Editor,Schizophrenia is one of the most complicated and serious psychiatric disorders, and patients often show markedly disrupted structural and functional abnormalities during resting-state imaging scans of the brain. Patients with firstepisode childhood- and adolescence-onset schizophrenia (CAOS) refers to individuals under the age of 18 years whose first episode of illness had occurred before they were 13 years old [1]. The symptoms are similar to adultonset schizophrenia-auditory hallucinations or language deficits and abnormal cognition. However, CAOS patients often present with more severe psychotic symptoms and have a worse prognosis and treatment effect [2]. 展开更多
关键词 SCHIZOPHRENIA Patients with firstepisode PROGNOSIS and treatment effect
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A novel biodegradable Mg-1Zn-0.5Sn alloy:Mechanical properties,corrosion behavior,biocompatibility,and antibacterial activity 被引量:7
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作者 Weikang Zhao Jingfeng Wang +4 位作者 Jiang Weiyang Bo Qiao Yiyang Wang yuling li Dianming Jiang 《Journal of Magnesium and Alloys》 SCIE 2020年第2期374-386,共13页
To meet the growing demand for antibacterial implants for bone-implant-associated infection therapy and avoid the adverse effects of secondary surgery,a degradable platform with pH responsiveness and ion-associated an... To meet the growing demand for antibacterial implants for bone-implant-associated infection therapy and avoid the adverse effects of secondary surgery,a degradable platform with pH responsiveness and ion-associated antibacterial properties was constructed.A small amount of Sn added to Mg-1Zn alloy reduces the biocorrosion rate,which can be attributed to Sn participation in outer-layer film formation,significantly reducing the biocorrosion rate and hydrogen evolution rate after implantation in vivo.These Mg alloys,which are susceptible to degradation in the acidic bacterial microenvironment,degrade by releasing Mg,Zn and Sn,producing favorably alkaline and antibacterial conditions.Samples with the composition of Mg-1Zn-0.5Sn were found to be beneficial for promoting initial cell adhesion and proliferation,resulting in improved biocompatibility and biosafety.The biocompatibility of this alloy was confirmed by the healthy behavior of animals and the absence of acute or chronic toxicity in the liver,spleen,and kidneys.Our results demonstrate that Mg-1Zn-0.5Sn is safe for biological systems,enabling its efficacious use in biomedical applications. 展开更多
关键词 Magnesium alloy Degradable materials ANTIBACTERIAL BIOSAFETY
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Influence of vegetation restoration on matrix structure and erosion resistance of iron tailings sites in eastern Hebei, China 被引量:2
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作者 Anning Wang Qiuxian Huang +2 位作者 Xuehua Xu Xiaogang li yuling li 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期969-980,共12页
The effects of vegetation restoration on matrix structure and erosion resistance of iron tailings were studied at dump sites in Malanzhuang, Qian'an, Hebei province, China. The restoration process involved soil sp... The effects of vegetation restoration on matrix structure and erosion resistance of iron tailings were studied at dump sites in Malanzhuang, Qian'an, Hebei province, China. The restoration process involved soil spray sowing restoration model with Rhus typhina, soil and iron tailings admixture spray sowing restoration model with Amorpha fruticosa Linn. and six-hole brick restoration model with Pinus tabulaeformis Carriere.–Amorpha fruticosa Linn. mixed-forest, and direct restoration model with Hippophae rhamnoides and Sabina vulgaris. Results show that the composition and distribution of particles and aggregates were closely related to erosion resistance(P < 0.05), indicating that matrix structure of iron tailings play an important role in erosion resistance. The improvement in matrix structure of iron tailings by the different restoration models was in the order of R. typhina soil spray sowing > A. fruticosa soil and iron tailings admixture spray sowing > mixed-forest six-hole brick >H. rhamnoides direct restoration > S. vulgaris direct restoration. The R. typhina soil spray sowing restorationmodel resulted in the greatest improvement in matrix structure of iron tailings, increasing the clay(10.6%) and large particle aggregates(18.7%) contents significantly(P < 0.01). Simultaneously, particle population, grading conditions(Cu= 28.86, Cs= 1.65), and aggregate stability(6.02) were significantly improved. The A. fruticosa soil and iron tailings admixture spray sowing restoration model,which effectively improved particle distribution(Cu-= 8.51, Cs= 1.07), increased the number of large aggregates considerably(9.6%), thereby increasing aggregate stability(6.2). The six-hole brick model significantly increased the number of large aggregates(4.0%) and improved the stability of aggregates(6.2). H. rhamnoides direct restoration improved the stability of aggregates(5.1)but showed no other significant improvements. The effect of S. vulgaris direct restoration on matrix structure of iron tailings was not significant. Due to its dependence on matrix structure of iron tailings, the erosion resistance of R.typhina soil spray sowing restoration model was the greatest, while that of S. vulgaris direct restoration was the weakest. There was no significant difference in the erosion resistance of the other models. Overall, vegetation restoration supplemented by soil spray sowing restoration and engineering measures is superior to in situ direct vegetation restoration in the short-term. In-situ direct restoration has long-term ecological significance because of its advanced concept of near-natural restoration and the advantages of low cost, easy operation, and low secondary damage. 展开更多
关键词 EROSION resistance Matrix structure Iron TAILINGS VEGETATION RESTORATION
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Sentiment Classification Based on Piecewise Pooling Convolutional Neural Network 被引量:2
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作者 Yuhong Zhang Qinqin Wang +1 位作者 yuling li Xindong Wu 《Computers, Materials & Continua》 SCIE EI 2018年第8期285-297,共13页
Recently,the effectiveness of neural networks,especially convolutional neural networks,has been validated in the field of natural language processing,in which,sentiment classification for online reviews is an importan... Recently,the effectiveness of neural networks,especially convolutional neural networks,has been validated in the field of natural language processing,in which,sentiment classification for online reviews is an important and challenging task.Existing convolutional neural networks extract important features of sentences without local features or the feature sequence.Thus,these models do not perform well,especially for transition sentences.To this end,we propose a Piecewise Pooling Convolutional Neural Network(PPCNN)for sentiment classification.Firstly,with a sentence presented by word vectors,convolution operation is introduced to obtain the convolution feature map vectors.Secondly,these vectors are segmented according to the positions of transition words in sentences.Thirdly,the most significant feature of each local segment is extracted using max pooling mechanism,and then the different aspects of features can be extracted.Specifically,the relative sequence of these features is preserved.Finally,after processed by the dropout algorithm,the softmax classifier is trained for sentiment classification.Experimental results show that the proposed method PPCNN is effective and superior to other baseline methods,especially for datasets with transition sentences. 展开更多
关键词 Sentiment classification convolutional neural network piecewise pooling feature extract
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Evaluation on Heat Transferring Performance of Fabric Heat Sink by Finite Element Modeling
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作者 Huashuai Zhang Jiyong Hu +1 位作者 Xudong Yang yuling li 《Journal of Textile Science and Technology》 2015年第1期25-32,共8页
Considering current technology limitation in manufacturing present pin fin heat sinks, a new fabric heat sink has been previously designed. However, there is a lack of an understanding of the heat transferring perform... Considering current technology limitation in manufacturing present pin fin heat sinks, a new fabric heat sink has been previously designed. However, there is a lack of an understanding of the heat transferring performance of this new kind of heat sink. Nowadays, finite element analysis has been generally developed for determining heat transfer from in-line and staggered pin fin heat sinks used in electronic packaging applications. In this study, this method is used to predict the heat transfer performance of the new heat sink with woven fabric structure, called fabric pin fin heat sink. Effect of the fin length and the material types made of heat sink on the thermal-structure response of the pin fin was investigated under forced convection. The results show that the minimum temperature of heat sink decreases with an increase of pin fin length,but the decreasing amplitude has decreased. Moreover, the heat transfer performance of fabric heat sink made of continuous carbon Fibers/Polymer (PPS) is worse than that of copper and of aluminum. 展开更多
关键词 Heat SINK Woven FABRIC PIN FIN Temperature
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Research progress in development and application of Calotropis gigantea fiber
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作者 Weiqiang li Junze Zhang +8 位作者 Tianyu Luo Jingge liu Gaojuan Zhao Jian Zhong Peng Chen Haifeng Zhang Jianchu Xu yuling li Gang li 《Circular Agricultural Systems》 2023年第1期70-75,共6页
Calotropis gigantea fiber(CGF)is to a type of seed fiber collected from the fruits of the Calotropis gigantea(CG).From a sustainable biomass resource,CGF is a naturally abundant cellulose fiber with good economic valu... Calotropis gigantea fiber(CGF)is to a type of seed fiber collected from the fruits of the Calotropis gigantea(CG).From a sustainable biomass resource,CGF is a naturally abundant cellulose fiber with good economic value,excellent biocompatibility and biodegradability.CGF has a high hollow structure and is lightweight,which means CGF has received increasing attention in recent years as the starting material for fabrication of different types of functional materials.In this paper,we have reviewed the morphology and characteristics of CGF,including its biological properties,chemical composition,and physical properties.Additionally,we provide an overview of the recent advancements in the extraction process,toughening treatment process,spinning process,and weaving process of CGF,which have garnered significant attention from researchers in the field.The applications of CGF in the fields of environment processing,antibacterial,and smart materials are also summarized.Finally,the challenges and development prospects of CGF are introduced with the ultimate goal of implementing its potential in real-world applications. 展开更多
关键词 FIBER summarized SPINNING
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Aging with Disabilities:Navigating the Dual Challenge of Aging and Disability in a Rapidly Aging Society with a Focus on China
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作者 Binbin Su Jincheng Chen +4 位作者 Chen Chen Yu Wu yuling li Xinran Shen Xiaoying Zheng 《China CDC weekly》 2025年第21期713-717,共5页
China faces the dual challenge of population aging and rising disability rates,creating an“aging-disability overlap”that places unprecedented pressure on the nation’s healthcare system.This paper analyzes the compl... China faces the dual challenge of population aging and rising disability rates,creating an“aging-disability overlap”that places unprecedented pressure on the nation’s healthcare system.This paper analyzes the complex mechanisms underlying the intersection of aging and disability,revealing that chronic and degenerative diseases are primary contributors to disability among older adults,with disability rates significantly increasing with age and comorbidities.Despite China’s implementation of long-term care insurance pilot programs and community-based elderly care services,multiple challenges persist:insufficient financing sustainability,inconsistent assessment standards,regional development imbalances,professional talent shortages,and social-cultural prejudices.In response,this paper proposes a comprehensive strategy framework aligned with“Healthy China 2030”’s goals of strengthening disability prevention and early intervention mechanisms;enhancing long-term care services with diversified security systems;fostering professional talent development in geriatric and rehabilitation medicine;promoting research and application of intelligent assistive technologies;and creating barrierfree communities within an inclusive social environment.Through these coordinated approaches,we aim to improve the quality of life for older adults with disabilities and facilitate dignified and highquality healthy aging. 展开更多
关键词 healthcare system chronic diseases DISABILITIES chronic degenerative diseases population aging AGING community based elderly care degenerative diseases
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Decomposition Analysis of Urban-Rural Disparities in Healthy Life Expectancy Among Older Adults—China,2010–2020
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作者 Shuai Guo Jiatong Gao +3 位作者 yuling li Zuliyaer Talifu Xu Wen Xiaoying Zheng 《China CDC weekly》 2025年第15期497-502,共6页
Introduction:As China’s population rapidly ages,concerns have emerged about whether increased longevity among older adults is accompanied by improvements in health status.Methods:This study analyzed data from the 201... Introduction:As China’s population rapidly ages,concerns have emerged about whether increased longevity among older adults is accompanied by improvements in health status.Methods:This study analyzed data from the 2010 and 2020 Chinese censuses to estimate healthy life expectancy(HLE)at age 60 and examined changes in urban-rural disparities and their driving factors.We applied the Sullivan method to estimate gender-and residence-specific HLE,while using the continuous change decomposition method to analyze how mortality and health status contributed to urban-rural differences.Results:Between 2010 and 2020,both the absolute years of HLE and its proportion of total life expectancy increased,with the urban-rural gap narrowing over time.However,the primary driver of urban-rural HLE disparities has shifted from mortality levels to health status,a pattern more pronounced among men.Decomposition analysis further reveals that compared to 2010,the key age groups contributing to urbanrural HLE disparities in 2020 have shifted to older ages,reflecting a transition in health inequalities as the population ages.These findings suggest that while HLE among China’s older population has improved,the nature of health inequalities is evolving.Conclusions:Future public health policies should place greater emphasis on addressing non-fatal health conditions,particularly in rural areas and among the oldest-old,by improving the accessibility and quality of health services to promote healthy aging and reduce urban-rural health disparities. 展开更多
关键词 AGING estimate healthy life expectancy hle Health Status MORTALITY Healthy Life Expectancy Decomposition Analysis Urban Rural Disparities continuous change decomposition method
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多氯联苯促进毛白杨不定根分化的效应
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作者 刘铭 刘霞 +2 位作者 孙然 李玉灵 杜克久 《植物学报》 CAS CSCD 北大核心 2018年第6期764-772,共9页
多氯联苯是一种典型的持久性有机污染物。研究表明多氯联苯具有毒物兴奋效应,但其影响植物生长发育的机制尚不清楚。以毛白杨(Populous tomentosa)组培苗为材料,探讨3mg·L^-1Aroclor1254对不定根分化、植物激素水平、与生长素相关... 多氯联苯是一种典型的持久性有机污染物。研究表明多氯联苯具有毒物兴奋效应,但其影响植物生长发育的机制尚不清楚。以毛白杨(Populous tomentosa)组培苗为材料,探讨3mg·L^-1Aroclor1254对不定根分化、植物激素水平、与生长素相关的P009g125900、P006g142600和P002g2227003因表达、与细胞分裂素相关的P005g2489和P005g2376基因表达的影响。结果显示,Aroclor1254可促进毛白杨组培苗不定根分化,缩短不定根初根时间与分化率达100%的时间,提高不定根数目:在不定根诱导期,用Aroclor1254单独诱导,IAA/(ZR+dhZR)比值与阳性对照无显著差异,P006g142600、P002g222700、P009g125900、P005g2489和P005g2376基因表达变化趋势与IBA单独诱导下各基因表达变化趋势一致。为验证Aroclor1254是否具有生长素效应,以玉米(Zea mays)和转生长素报告基因DR5::GUS的拟南芥(Arabidopsis thaliana)为材料,观察Aroclor1254对胚芽鞘生长及DR5::GUS基因表达的影响。结果显示,一定浓度的Aroclor1254对胚芽鞘的生长无显著影响,但可诱导生长素报告基因表达。以上结果表明,多氯联苯类化合物Aroclor1254虽不属于植物生长调节剂,但具有毒物兴奋效应,在一定浓度下具有类似生长素的生物学活性。 展开更多
关键词 Aroclor1254 不定根分化 植物激素 基因表达 胚芽鞘 DR5::GUS
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常压电喷雾离子化的机理及应用 被引量:8
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作者 李瑜玲 赵君博 郭寅龙 《化学进展》 SCIE CAS CSCD 北大核心 2019年第1期94-109,共16页
作为最有前景的分析仪器之一,质谱技术已在药物、食品、环境、人类健康、国家安全及相关领域展现出广阔的应用前景。不同种类的分析物具有多种特征,这为直接离子化及质谱分析增加了难度。常压敞开式离子源是近年来新兴的一种离子源,这... 作为最有前景的分析仪器之一,质谱技术已在药物、食品、环境、人类健康、国家安全及相关领域展现出广阔的应用前景。不同种类的分析物具有多种特征,这为直接离子化及质谱分析增加了难度。常压敞开式离子源是近年来新兴的一种离子源,这类离子源具有无需复杂的样品前处理、操作方便、快速、非破坏性、灵敏度及特异性好、能实现实时原位、高通量分析等特点。本文综述了基于电喷雾离子化(ESI)原理的各种离子源的电离机理、特征及应用,展望了常压敞开式离子源的发展趋势。 展开更多
关键词 质谱 电喷雾离子化 敞开式离子化 离子化机理 质谱成像
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基于多个叶绿体基因序列片段重建广义苋科系统发育关系 被引量:2
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作者 黄久香 陈文娜 +1 位作者 李玉玲 姚纲 《植物学报》 CAS CSCD 北大核心 2020年第4期457-467,共11页
苋科(Amaranthaceaesensulato)是石竹目(Caryophyllales)第二大科,目前被普遍接受的苋科为其广义概念,含狭义苋科(Amaranthaceae sensu stricto)和藜科(Chenopodiaceae)。然而到目前为止,藜科是否应作为独立的科还存在争议。此外,广义... 苋科(Amaranthaceaesensulato)是石竹目(Caryophyllales)第二大科,目前被普遍接受的苋科为其广义概念,含狭义苋科(Amaranthaceae sensu stricto)和藜科(Chenopodiaceae)。然而到目前为止,藜科是否应作为独立的科还存在争议。此外,广义苋科内部各亚科之间的系统关系也尚未厘清。对广义苋科所有13个亚科代表类群进行取样(共59种),基于8个叶绿体序列片段重建其系统发育关系,并结合分子钟估算,对该科及其主要分支的起源与分化时间进行推测。结果表明,广义苋科与狭义苋科都是很好的单系,但藜科并非单系,因此不支持藜科在科级水平的地位,支持广义苋科的观点。除了多节草亚科(Polycnemoideae)之外,其它亚科的系统位置均得到很好的分辨。分子钟估算结果表明,广义苋科于白垩纪晚期约69.9Ma分化出该科的2个主要分支,且该科在白垩纪-古近纪边界附近时期(约66.0Ma)可能发生过快速辐射分化事件。 展开更多
关键词 苋科 石竹目 分化时间 系统发育
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Spatial pattern and mechanisms of farmland abandonment in Agricultural and Pastoral Areas of Qingzang Plateau 被引量:3
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作者 yuling li Tao Zhou +3 位作者 Guanghui Jiang Guangyong li Dingyang Zhou Yu Luo 《Geography and Sustainability》 2021年第3期139-150,共12页
With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly... With the rapid development of social economy and urban−rural integration,the phenomenon of farmland aban-donment worldwide has proved to be one of the main trends of land use and land cover change(LUCC),and profoundly affected the rural landscape and regional ecological environment.Restricted by the natural environ-ment,economic development and backward agricultural technology,the phenomenon of farmland abandonment is also common in the Qingzang Plateau(QP).Therefore,this paper adopted the spatial autocorrelation method to analyze the spatial pattern of abandonment in the agricultural and pastoral areas of the Qingzang Plateau(APA−QP)in 2017,and the geographically weighted regression(GWR)model to explore the effects of geograph-ical resources,socio-economic development and location conditions on farmland abandonment.This study found that:1)From 2015 to 2017,the abandoned farmland area in the APA−QP was approximately 18.23×10^(4)ha,with an overall abandonment rate of 15.18%.On the whole,it showed the distribution characteristics of“strong in the south and weak in the north,strong in the east and weak in the west”.2)There were positive spatial correlation between both abandoned area and abandonment rate in the APA−QP,showing“concave”and“convex”patterns,respectively,mainly concentrated in the Huang−shui Valley and the Southeast Tibet;while in the western and northern regions,the degree of abandonment was relatively low.3)Farmland abandonment in the APA−QP was mainly driven by the geographical environment changes and farmers’decision−making on farmland utilization.There was significant spatial heterogeneity on farmland abandonment associated with the impact of geographical resources,socio−economics and location conditions.The geographical resource factors had a positive impact on the abandonment,and were strongly constrained by natural geographic conditions such as altitude and slope.The farmland resources in the Qingzang Plateau are limited,but are of strategic significance for the sustainable development of agriculture in the whole Qingzang Plateau.In order to realize the rational distribution of agricul-ture and animal husbandry and the sustainable utilization of farmland resources in the plateau region,land use strategies should be implemented according to regional differences and regional advantages in order to ensure the ecological environment security of Qingzang Plateau. 展开更多
关键词 Farmland abandonment Spatial pattern Formation mechanism Geographically weighted regression Qingzang Plateau Agricultural and pastoral areas
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Phylogenetic estimation and morphological evolution of Alsineae(Caryophyllaceae)shed new insight into the taxonomic status of the genus Pseudocerastium 被引量:1
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作者 Gang Yao Bine Xue +3 位作者 Kun liu yuling li Jiuxiang Huang Junwen Zhai 《Plant Diversity》 CSCD 2021年第4期299-307,共9页
Pseudocerastium is a monotypic genus in Caryophyllaceae endemic to China.The genus has been widely accepted since it was described in 1998,however its phylogenetic position within Caryophyllaceae has never been studie... Pseudocerastium is a monotypic genus in Caryophyllaceae endemic to China.The genus has been widely accepted since it was described in 1998,however its phylogenetic position within Caryophyllaceae has never been studied.In the present study,the whole plastid genome and nuclear ribosomal internal transcribed spacer(ITS)sequences of Pseudocerastium stellarioides was obtained through genome skimming,and the phylogenetic position of the species was studied for the first time.Plastid phylogenomic analysis of Caryophyllaceae revealed that Pseudocerastium is clustered within the tribe Alsineae with strong support.Phylogenetic analyses based on an enlarged taxon sampling of Alsineae using five DNA regions(matK,rbcL,rps16 intron,trnL-F and ITS)revealed that P.stellarioides was nested deeply within Cerastium with strong support.Analyses of morphological character evolution suggest that the ancestral states in Alsineae include three styles and a six-lobed capsule at the apex,while both Cerastium and Pseudocerastium have five styles and ten lobes at the apex of the capsule,further supporting their close relationship.The species Pseudocerastium stellarioides is similar to Cerastium wilsonii in morphology,but differs in having villous indumentum on the lower part of the filaments and compressed globose seeds.Therefore,based on the present molecular and morphological evidence,the generic name Pseudocerastium is reduced here as a new synonym of Cerastium and the species P.stellarioides is transferred to Cerastium as C.jiuhuashanense. 展开更多
关键词 Alsineae Cerastium Character evolution Genome skimming Molecular phylogeny TAXONOMY
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The Situation and Educational Development of University Auditing
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作者 yuling li 《International Journal of Technology Management》 2015年第4期73-75,共3页
Auditing is a kind of practical economical subject, with a strong practical and operational. It is the backbone course of accounting major and plays a crucial role in the professional cultivation. But recently, in sta... Auditing is a kind of practical economical subject, with a strong practical and operational. It is the backbone course of accounting major and plays a crucial role in the professional cultivation. But recently, in stage of our country university education, audition' s teaching effectiveness is almost the lowest in all the core curriculum of accounting professional. Students generally reflect that Auditing is difficult to learn and abstract, while the teachers of auditing courses also reflect students have low interest in auditing learning, meanwhile there is less relevant case, fewer choices and other materials. This paper analyzes the problems and limitations of the auditing teaching, proposes measures about the teaching reform of university auditing, and finally makes our own suggestions about the reform measures of our university auditing teaching research. 展开更多
关键词 AUDIT teaching situation PRACTICE RESEARCH
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