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Distinct molecular targets of ProEGCG from EGCG and superior inhibition of angiogenesis signaling pathways for treatment of endometriosis
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作者 Sze Wan Hung Massimiliano Gaetani +12 位作者 yiran li Zhouyurong Tan Xu Zheng Ruizhe Zhang Yang Ding Gene Chi Wai Man Tao Zhang Yi Song Yao Wang Jacqueline Pui Wah Chung Tak Hang Chan Roman A.Zubarev Chi Chiu Wang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第1期100-114,共15页
Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the uterus.Angiogenesis is a major pathophysiology in endometriosis.Our previous studies have demonstrated that the pr... Endometriosis is a common chronic gynecological disease with endometrial cell implantation outside the uterus.Angiogenesis is a major pathophysiology in endometriosis.Our previous studies have demonstrated that the prodrug of epigallocatechin gallate(ProEGCG)exhibits superior anti-endometriotic and anti-angiogenic effects compared to epigallocatechin gallate(EGCG).However,their direct binding targets and underlying mechanisms for the differential effects remain unknown.In this study,we demonstrated that oral ProEGCG can be effective in preventing and treating endometriosis.Additionally,1D and 2D Proteome Integral Solubility Alteration assay-based chemical proteomics identified metadherin(MTDH)and PX domain containing serine/threonine kinase-like(PXK)as novel binding targets of EGCG and ProEGCG,respectively.Computational simulation and BioLayer interferometry were used to confirm their binding affinity.Our results showed that MTDH-EGCG inhibited protein kinase B(Akt)-mediated angiogenesis,while PXK-ProEGCG inhibited epidermal growth factor(EGF)-mediated angiogenesis via the EGF/hypoxia-inducible factor(HIF-1a)/vascular endothelial growth factor(VEGF)pathway.In vitro and in vivo knockdown assays and microvascular network imaging further confirmed the involvement of these signaling pathways.Moreover,our study demonstrated that ProEGCG has superior therapeutic effects than EGCG by targeting distinct signal transduction pathways and may act as a novel antiangiogenic therapy for endometriosis. 展开更多
关键词 Molecular targets ProEGCG EGCG ANGIOGENESIS TREATMENT ENDOMETRIOSIS
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The component-activity interrelationship of cobalt-based bifunctional electrocatalysts for overall water splitting:Strategies and performance
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作者 Mingjie Sun Riyue Ge +4 位作者 Sean li liming Dai yiran li Bin liu Wenxian li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期453-474,共22页
Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysi... Cobalt-based electrocatalysts take advantage of potentially harmonizable microstructure and flexible coupling effects compared to commercial noble metal-based catalytic materials.However,conventional water electrolysis systems based on cobalt-based monofunctional hydrogen evolution reaction(HER)or oxygen evolution reaction(OER)catalysts have certain shortcomings in terms of resource utilization and universality.In contrast,cobalt-based bifunctional catalysts(CBCs)have attracted much attention in recent years for overall water splitting systems because of their practicality and reduced preparation cost of electrolyzer.This review aims to address the latest development in CBCs for total hydrolysis.The main modification strategies of CBCs are systematically classified in water electrolysis to provide an overview of how to regulate their morphology and electronic configuration.Then,the catalytic performance of CBCs in total-hydrolysis is summarized according to the types of cobalt-based phosphides,sulfides and oxides,and the mechanism of strengthened electrocatalytic ability is emphasized through combining experiments and theoretical calculations.Future efforts are finally suggested to focus on exploring the dynamic conversion of reaction intermediates and building near-industrial CBCs,designing advanced CBC materials through micro-modulation,and addressing commercial applications. 展开更多
关键词 COBALT Bifunctional electrocatalysis Water splitting Modification strategies Electrocatalytic performances
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Developing an atmospheric aging evaluation model of acrylic coatings:A semi-supervised machine learning algorithm
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作者 yiran li Zhongheng Fu +5 位作者 Xiangyang Yu Zhihui Jin Haiyan Gong lingwei Ma Xiaogang li Dawei Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1617-1627,共11页
To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in China.An atmospheric aging evaluation model of acrylic coatings was d... To study the atmospheric aging of acrylic coatings,a two-year aging exposure experiment was conducted in 13 representative climatic environments in China.An atmospheric aging evaluation model of acrylic coatings was developed based on aging data including11 environmental factors from 567 cities.A hybrid method of random forest and Spearman correlation analysis was used to reduce the redundancy and multicollinearity of the data set by dimensionality reduction.A semi-supervised collaborative trained regression model was developed with the environmental factors as input and the low-frequency impedance modulus values of the electrochemical impedance spectra of acrylic coatings in 3.5wt%NaCl solution as output.The model improves accuracy compared to supervised learning algorithms model(support vector machines model).The model provides a new method for the rapid evaluation of the aging performance of acrylic coatings,and may also serve as a reference to evaluate the aging performance of other organic coatings. 展开更多
关键词 acrylic coatings coatings aging atmospheric environment machine learning
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多囊卵巢综合征无排卵的胰岛素信号和雄激素合成的新遗传风险和代谢特征 被引量:2
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作者 吴效科 黄志超 +24 位作者 曹义娟 李建 李志强 马红丽 高敬书 常惠 张多加 丛晶 王宇 吴奇 Xiaoxiao Han Pui Wah Jacqueline Chung yiran li Xu Zheng lingxi Chen lin Zeng Astrid Borchert Hartmut Kuhn Zi-Jiang Chen Ernest Hung Yu Ng Elisabet Stener-Victorin 张和平 Richard S.Legro Ben Willem J.Mol 师咏勇 《Engineering》 SCIE EI CAS CSCD 2023年第4期103-111,M0005,M0006,共11页
促排卵是多囊卵巢综合征(PCOS)不孕症的一线治疗方案。卵巢对促排卵治疗的排卵应答差被认为与胰岛素抵抗和高雄激素血症相关。在一个包含1000名PCOS不孕妇女(PCOSAct)的前瞻性队列中,我们开展了一项全外显子联合靶向单核苷酸多态性(SNP... 促排卵是多囊卵巢综合征(PCOS)不孕症的一线治疗方案。卵巢对促排卵治疗的排卵应答差被认为与胰岛素抵抗和高雄激素血症相关。在一个包含1000名PCOS不孕妇女(PCOSAct)的前瞻性队列中,我们开展了一项全外显子联合靶向单核苷酸多态性(SNP)测序以及代谢组学研究。在全基因组水平找出与无排卵显著相关的常见变异和罕见突变,并通过机器学习算法构建排卵预测模型。研究发现,ZNF438基因中标记为rs2994652(p=2.47×10^(-8))的常见变异和REC114基因中的一个罕见功能突变(rs182542888,p=5.79×10^(-6))与促排卵治疗失败显著相关。携带rs2994652 A等位基因和REC114 p.Val101Leu(rs182542888)的PCOS不孕妇女进行促排卵治疗的总排卵率更低(分别为比值比(OR)=1.96,95%置信区间(CI)[1.55~2.49];OR=11.52,95%CI[3.08~43.05]),出现排卵的间隔时间更长(平均56.7天vs.49.0天,p<0.001;78.1天vs.68.6天,p=0.014)。对于rs2994652突变者,L-苯丙氨酸水平升高并与胰岛素抵抗稳态模型(HOMA-IR)指数(r=0.22,p=0.05)和空腹血糖(r=0.33,p=0.003)呈正相关;对于rs182542888突变者,花生四烯酸代谢产物水平下降并与升高的抗苗勒管激素(r=-0.51,p=0.01)和总睾酮(r=-0.71,p=0.02)呈负相关。整合基因变异位点、代谢产物及临床特征的联合预测模型可提高对排卵的预测能力[曲线下面积(AUC)=76.7%]。ZNF438基因的一个常见变异和REC114基因的一个罕见功能突变,以及与二者相关的苯丙氨酸和花生四烯酸代谢物改变,与PCOS女性不孕症的促排卵治疗失败相关。 展开更多
关键词 Polycystic ovary syndrome INFERTILITY Ovulation responses ZNF438 REC114 Whole-exome sequencing Deep machine learning
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3D Geometry-Based UAV-MIMO Channel Modeling and Simulation 被引量:14
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作者 Rubing Jia yiran li +1 位作者 Xiang Cheng Bo Ai 《China Communications》 SCIE CSCD 2018年第12期64-74,共11页
A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) ... A more general narrowband regular-shaped geometry-based statistical model(RS-GBSM) combined with the line of sight(LoS) and single bounce(SB) rays for unmanned aerial vehicle(UAV) multiple-input multiple-output(MIMO) channel is proposed in this paper. The channel characteristics, including space-time correlation function(STCF), Doppler power spectral density(DPSD), level crossing rate(LCR) and average fade duration(AFD), are derived based on the single sphere reference model for a non-isotropic environment. The corresponding sum-of-sinusoids(SoS) simulation models including both the deterministic model and statistical model with finite scatterers are also proposed for practicable implementation. The simulation results illustrate that the simulation models well reproduce the channel characteristics of the single sphere reference model with sufficient simulation scatterers. And the statistical model has a better approximation of the reference model in comparison with the deterministic one when the simulation trials of the stochastic model are sufficient. The effects of the parameters such as flight height, moving direction and Rice factor on the characteristics are also studied. 展开更多
关键词 UAV-MIMO geometry-based MODEL CHANNEL CHARACTERISTICS simulation MODEL
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Natural infectious behavior of the urediniospores of Melampsora larici-populina on poplar leaves 被引量:1
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作者 Zhibing Wan yiran li +2 位作者 Min liu Yingnan Chen Tongming Yin 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第1期225-231,共7页
The uredinial stage in the life cycle of Melampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the pro... The uredinial stage in the life cycle of Melampsora larici-populina on poplar leaves is the most important pathogenic phase. We captured partial phases of uredinial infection in the wild, aiming to reconstruct the process of uredinial ontogeny by using scanning and transmission electron microscope. At the initial infection stage, germ tubes germinated from the echinulate urediniospores. Germ tubes were frequently seen to merge with the leaf surface and cuticle breakage was observed, indicating direct hyphal penetration. Stomata penetration occurred commonly, sometimes with more than one germ tube penetrating the same stoma. Melampsora larici-populina did not form appressoria in the infection process,implying that infectious behavior of this pathogen may differ from the other rust pathogens. In general, germ tubes branched randomly, and no distinct evidence indicated that stoma could induce or orient germ tube branches. However, oriented germ tube growth has been occasionally observed in other studies. The urediniospores collapsed and finally wizened when they became nutrient stressed. At the last stage of infection, the uredinia erupted from the leaf epidermis and appeared as orange pustules on the leaf surface. 展开更多
关键词 Populus deltoides Melampsora laricipopulina Germ tube Infectious behavior
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Deterministic and Stochastic Simulators for Non-Isotropic V2V-MIMO Wideband Channels 被引量:6
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作者 yiran li Xiang Cheng Nan Zhang 《China Communications》 SCIE CSCD 2018年第7期18-29,共12页
In this paper, we consider a novel two-dimensional(2D) geometry-based stochastic model(GBSM) for multiple-input multiple-output(MIMO) vehicle-to-vehicle(V2V) wideband fading channels. The proposed model employs the co... In this paper, we consider a novel two-dimensional(2D) geometry-based stochastic model(GBSM) for multiple-input multiple-output(MIMO) vehicle-to-vehicle(V2V) wideband fading channels. The proposed model employs the combination of a two-ring model and a multiple confocal ellipses model, where the signal is sum of the line-of-sight(Lo S) component, single-bounced(SB) rays, and double-bounced(DB) rays. Based on the reference model, we derive some expressions of channel statistical properties, including space-time correlation function(STCF), Doppler spectral power density(DPSD), envelope level crossing rate(LCR) and average fade duration(AFD). In addition, corresponding deterministic and stochastic simulation models are developed based on the reference model. Moreover, we compare the statistical properties of the reference model and the two simulation models in different scenarios and investigate the impact of different vehicular traffic densities(VTDs) on the channel statistical properties of the proposed model. Finally, the great agreement between simulation models and the reference model demonstrates not only the utility of simulation models, but also the correctness of theoretical derivations and simulations. 展开更多
关键词 vehicle-to-vehicle wideband channels simulation model statistical properties
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“铑”有所“铱” 被引量:2
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作者 李一冉 姚力筝 +2 位作者 董梓凝 颜静 闫毅 《大学化学》 CAS 2021年第10期21-25,共5页
铑和铱是两种稀有的铂系元素,性质十分相似。本文以第三人称拟人化的口吻,通过游戏闯关的形式对两种单质的沸点、反射率、弹性模量、催化活性和化学稳定性等物理化学性质进行介绍。还穿插讲述了其氧化物和卤化物的性质以及在电镀层、汽... 铑和铱是两种稀有的铂系元素,性质十分相似。本文以第三人称拟人化的口吻,通过游戏闯关的形式对两种单质的沸点、反射率、弹性模量、催化活性和化学稳定性等物理化学性质进行介绍。还穿插讲述了其氧化物和卤化物的性质以及在电镀层、汽车尾气催化转化器、热电偶等领域的应用。 展开更多
关键词 铱铑合金
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Lrrc34 Is Highly Expressed in SSCs and Is Necessary for SSC Expansi on In Vitro
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作者 Jinhuan Ou yiran li +9 位作者 Zhipeng Wang Cheng Jin Kai li Yan Lu Dingfeng Zou Pengyu li Mengzhen li Shiying Miao linfang Wang Wei Song 《Chinese Medical Sciences Journal》 CAS CSCD 2020年第1期20-30,共11页
Objective To discover critical genes contributing to the sternness and maintenance of spermatogonial stem cells(SSCs)and provide new insights into the function of the leucine-rich repeat(LRR)family member Lrrc34(leudn... Objective To discover critical genes contributing to the sternness and maintenance of spermatogonial stem cells(SSCs)and provide new insights into the function of the leucine-rich repeat(LRR)family member Lrrc34(leudne-rich repeat-containing 34)in SSCs from mice.Methods Bioinformatic methods,including differentially expressed gene(DEG),gene ontology(GO)enrichment and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analyses,were used to uncover latent pluripotency-related genes.Reverse transcription-polymerase chain reaction(RT-PCR)and immunofluorescence analyses were utilized to verify the mRNA and protein expression levels,respectively.RNA interference of Lrrc34 using siRNA was performed to detect its transient impact on SSCs.Results Eight DEGs between ID4-EGFP+(G)and ID4-EGFP+/TSPAN8Hig11(TH),eight DEGs between G and ID4-EGFP+/TSPAN8Uw(TL)and eleven DEGs between TH and TL were discovered,and eleven proteinprotein interaction(PPI)modules were found to be significant in the PPI network of DEGs.One of the DEGs,Lrrc34,was selected as a potential pluripotency?related gene due to its differential expression among ID4-EGFP+spermatogonia subsets and its interaction with fibroblast growth factor 2 in the fifth module.Immunofluorescence experiments exhibited specific expression of Lrrc34 in a subpopulation of undifferentiated spermatogonia marked by LIN28A,and RT-PCR experiments confirmed the high expression of Lrrc34 in SSCs from P7 and adult mice.The transient knockdown of Lrrc34 in SSCs resulted in reduced colony sizes and significant changes in the transcriptome and apoptotic pathways.Conclusion Lrrc34 is highly expressed in mouse SSCs and is required for SSC proliferation in vitro through effects on transcriptome and signaling transduction pathways. 展开更多
关键词 spermatogonial STEM cells Lrrc34 high expression APOPTOSIS
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“食”游记之“火眼金睛辨凝妖”
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作者 董梓凝 姚力筝 +7 位作者 李一冉 郑非凡 蔡梓曦 石朝阳 蔡宁静 王景源 颜静 闫毅 《大学化学》 CAS 2021年第10期107-112,共6页
水凝胶是一种具有三维网络结构的高分子,在食品、日常用品和高科技等领域都有着广泛应用。本文以天然水凝胶和合成水凝胶在食品领域的几个应用为例,一方面,从食品化学的角度介绍了西安地域美食文化中具有天然水凝胶结构的多种美食以及... 水凝胶是一种具有三维网络结构的高分子,在食品、日常用品和高科技等领域都有着广泛应用。本文以天然水凝胶和合成水凝胶在食品领域的几个应用为例,一方面,从食品化学的角度介绍了西安地域美食文化中具有天然水凝胶结构的多种美食以及其所涉及的化学原理。同时也介绍了水凝胶食品中添加硼砂、工业明胶和明矾的潜在健康危害和辨别方法;另一方面还穿插介绍了水凝胶的性质和前沿应用。 展开更多
关键词 水凝胶 美食 食品安全
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Investigation on the Velocity-Dependent Adhesion Hysteresis via Molecular Dynamics Simulation 被引量:1
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作者 Jinshan He yiran li +1 位作者 Zhaoyang Ma Ganyun Huang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2024年第3期423-429,共7页
Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion hysteresis.In the pr... Adhesion plays an important role in miniaturized devices and technologies,which depends not only on indentation depth but also on the history of contact making and breaking,giving rise to adhesion hysteresis.In the present work,adhesion hysteresis has been investigated via molecular dynamics simulations on approaching and retracting a rigid tip to and from a substrate.The results show that hysteresis in the force-displacement curve that depends on approaching and retraction velocities arises under both elastic and plastic deformation.The underlying mechanisms have been analyzed.The implications of the results in friction have been discussed briefly. 展开更多
关键词 Adhesion hysteresis Molecular dynamics simulation Contact instability Plastic deformation
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高吸附电化学纤维传感器用于实时、准确检测颅内一氧化氮
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作者 高睿 王列 +12 位作者 李丹 宋杰 栗乾明 卢江 李录河 李亦冉 叶婷婷 王嘉诚 焦一丁 李方琰 何儿 任俊烨 张晔 《Science China Materials》 SCIE EI CAS CSCD 2024年第4期1320-1331,共12页
电化学一氧化氮传感器能够实时监测颅内一氧化氮浓度,对于了解大脑中一氧化氮的功能至关重要.然而,在大脑中使用的传统刚性传感电极面临着灵敏度低和植入后神经炎症引起一氧化氮浓度异常的问题.在这里,我们报道了一种结合物理和化学吸... 电化学一氧化氮传感器能够实时监测颅内一氧化氮浓度,对于了解大脑中一氧化氮的功能至关重要.然而,在大脑中使用的传统刚性传感电极面临着灵敏度低和植入后神经炎症引起一氧化氮浓度异常的问题.在这里,我们报道了一种结合物理和化学吸附能力、具有高灵敏度和准确性的电化学一氧化氮传感器.其对一氧化氮的物理和化学吸附能力分别来自于电极的高比表面积和丰富的羧基官能团.此外,柔软的电极可以与脑组织的力学性能相匹配,实现了一个高度适应的电极/组织界面.由此设计的颅内一氧化氮传感器表现出迄今为止所报道文献中最高的灵敏度,为3245 pA nmol^(-1)L,检测限为0.1 nmol L^(-1).电极在植入后未观察到显著的炎症反应以及过量的一氧化氮表达,提高了检测的准确性.该传感器成功捕捉了大脑中的一氧化氮波动,并实现了对多个脑区的同时检测,促进了对大脑中一氧化氮生理病理作用的研究. 展开更多
关键词 一氧化氮浓度 生理病理 传感电极 化学纤维 组织界面 电化学
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Unique anti-angiogenic effects,pharmacological targets and therapeutic mechanisms of Chinese herbal medicines for endometriosis
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作者 Bo liang Rui Dong +8 位作者 Sze Wan Hung yiran li Yuezhen lin ling Wu Tao Zhang Gene Chi Wai Man Hui Xu Jacqueline Pui Wah Chung Chi Chiu Wang 《Genes & Diseases》 SCIE CSCD 2024年第5期63-65,共3页
Endometriosis is a common and benign angiogenesisdependent gynecological disorder,which refers to the proliferation and growth of endometrium-like tissues with neovasculature formation outside of the uterus.1 Availabl... Endometriosis is a common and benign angiogenesisdependent gynecological disorder,which refers to the proliferation and growth of endometrium-like tissues with neovasculature formation outside of the uterus.1 Available medical treatments for endometriosis containing hormonal and non-hormonal treatments had been limited for longterm usage by their side effects.2 Ideal medical treatment for endometriosis with efficacy to relieve symptoms and suppress endometriotic lesion growth and minimal side effects has been longing for decades.3 Angiogenesis is a promising therapeutic target for endometriosis. 展开更多
关键词 THERAPEUTIC ENDOMETRIOSIS HERBAL
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Pathogenic role of microRNAs in atherosclerotic ischemic stroke:Implications for diagnosis and therapy 被引量:1
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作者 Qidi Jiang yiran li +3 位作者 Quanli Wu li Huang Jiasheng Xu Qingfu Zeng 《Genes & Diseases》 SCIE 2022年第3期682-696,共15页
Ischemic stroke resulting from atherosclerosis(particularly in the carotid artery)is one of the major subtypes of stroke and has a high incidence of death.Disordered lipid homeostasis,lipid deposition,local macrophage... Ischemic stroke resulting from atherosclerosis(particularly in the carotid artery)is one of the major subtypes of stroke and has a high incidence of death.Disordered lipid homeostasis,lipid deposition,local macrophage infiltration,smooth muscle cell proliferation,and plaque rupture are the main pathological processes of atherosclerotic ischemic stroke.Hepatocytes,macrophages,endothelial cells and vascular smooth muscle cells are the main cell types participating in these processes.By inhibiting the expression of the target genes in these cells,microRNAs play a key role in regulating lipid disorders and atherosclerotic ischemic stroke.In this article,we listed the microRNAs implicated in the pathology of atherosclerotic ischemic stroke and aimed to explain their pro-or antiatherosclerotic roles.Our article provides an update on the potential diagnostic use of miRNAs for detecting growing plaques and impending clinical events.Finally,we provide a perspective on the therapeutic use of local microRNA delivery and discuss the challenges for this potential therapy. 展开更多
关键词 Atherosclerotic ischemic stroke ECS MACROPHAGES miRNA Plaque stability VSMCS
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Evaluation of the performance of a centralized ground-water heat pump system in cold climate region 被引量:1
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作者 Shilei LU Zhe CAI +1 位作者 yiran li li ZHANG 《Frontiers in Energy》 SCIE CSCD 2014年第3期394-402,共9页
The aim of this study is to performance of a centralized open-loop evaluate the ground-water heat pump (GWHP) system for climate conditioning in Beijing with a cold climate in China. Thus, a long-time test was condu... The aim of this study is to performance of a centralized open-loop evaluate the ground-water heat pump (GWHP) system for climate conditioning in Beijing with a cold climate in China. Thus, a long-time test was conducted on a running GWHP system for the heating season from December 2011 to March 2012. The analysis of the testing data indicates that the average heat-pump coefficient of performance (COP) and the COP of the system (COPs) are 4.27 and 2.59. The low value and large fluctuation in the range of COP are found to be caused by the heat transfixion in the aquifer and the bypass in the circulation loop. Therefore, some suggestions are proposed to improve the performance for GWHPs in the cold climate region in China. 展开更多
关键词 ground-water heat pump (GWHP) actualcoefficient of performance heat transfixion
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UAV Communication Channel Measurement, Modeling, and Application 被引量:1
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作者 Xiang Cheng yiran li lin Bai 《Journal of Communications and Information Networks》 CSCD 2019年第4期32-43,共12页
As unmanned aerial vehicles(UAV)deploy-ment is shifting from military to civilian sectors,and in particular as a means of facilitating more flexible and versatile wireless communications,the UAV channels that were pre... As unmanned aerial vehicles(UAV)deploy-ment is shifting from military to civilian sectors,and in particular as a means of facilitating more flexible and versatile wireless communications,the UAV channels that were previously not well understood are attracting increasing research and investigation.As the key component facilitating the UAV-aided communications,UAV channel characteristics and modeling are of critical importance to the designed UAV system to achieve satisfactory performance.In this article,we will provide a comprehensive overview and the future perspective of envisioned UAV communication system benefits,the existing and needed UAV channel measurements and modeling approaches,together with the new viewpoint of UAV channel applications in different communication and networking layers.Both existing work and future directions are extensively covered. 展开更多
关键词 UAV channel MEASUREMENTS MODELING application future challenges
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A Dislocation-based Model for the Dynamics of Sliding Precursors
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作者 yiran li Ganyun Huang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2021年第5期624-631,共8页
The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields ha... The onset of dynamic friction plays an important role in the study of sliding interfaces.Previously,the sliding precursors in the form of crack-like defects have been detected in experiments and their strain fields have been measured to be comparable to those of moving cracks.In the present work,we considered the dynamics of sliding precursors by solving the elastic problem due to a moving dislocation in a half-plane and the transient emission of a dislocation at the edge.It has been found that both the strain field of a moving dislocation and the spatiotemporal evolution agree well with those of a sliding precursor detected in experiments.The results may cast new light to the dynamics of sliding onset. 展开更多
关键词 Sliding precursor Crack-like defects Moving dislocations Dislocation emission
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Diselenide as a Dual Functional Mechanophore Capable of Stress Self-Reporting and Self-Strengthening in Polyurethane Elastomers 被引量:1
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作者 Xiaopei li Fan Yang +5 位作者 yiran li Cheng liu Peng Zhao Yi Cao Huaping Xu Yulan Chen 《CCS Chemistry》 CSCD 2023年第4期925-933,共9页
Unlike biological materials that can sense mechanical force and actively remodel locally,synthetic polymers typically break down under stress.Molecular-level responses to damage with both stress-reporting and self-str... Unlike biological materials that can sense mechanical force and actively remodel locally,synthetic polymers typically break down under stress.Molecular-level responses to damage with both stress-reporting and self-strengthening functions are significant yet difficult to realize for synthetic polymers.To overcome this challenge,chemo-mechanical coupling into polymers that can simultaneously ameliorate mechanical,optical,or other functional properties of a polymer combined with mechanical treatment will offer a new principle for materials design.Here,we report a kind of elastomer in which destructive forces are channelled into productive and bond-forming reactions by using diselenide(Se–Se)as a mechanophore.Polyurethane has been functionalized with labile Se–Se bonds,whosemechanical activation generates seleno radicals that trigger radical transfer and cross-linking reactions in situ.These reactions are activated efficiently in a mechanical way by compression in bulk materials.The resulting covalent networks possess turn-on mechano-fluorescence and increased moduli,which provide the functions of stress reporting,mechano-healing,and mechano-remodeling for the deformed film.This study not only illuminates themechano-responsive nature of Se–Se bonds in the bulk state but also paves the way for the development of new stress-responsive materials. 展开更多
关键词 DISELENIDE mechano-responsive polymers SELF-STRENGTHENING polymermechanochemistry stress sensing
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国家自然科学基金经费管理改革实践与思考 被引量:4
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作者 郭蕾 张香平 +4 位作者 高亮 李依然 郭彦君 张丽婧 聂建青 《中国科学基金》 CSSCI CSCD 北大核心 2022年第5期798-805,共8页
科研经费作为科研活动的基础保障,其应用效能直接影响科技创新成效。在国家科研经费管理“放管服”改革背景下,科学基金项目经费管理持续优化,通过更加符合科研规律的经费管理政策引导,有效释放科技创新动能,激发创新活力。文章通过梳... 科研经费作为科研活动的基础保障,其应用效能直接影响科技创新成效。在国家科研经费管理“放管服”改革背景下,科学基金项目经费管理持续优化,通过更加符合科研规律的经费管理政策引导,有效释放科技创新动能,激发创新活力。文章通过梳理近年来国家自然科学基金经费管理改革举措,分析经费管理改革成效,结合国家自然科学基金经费使用和管理实际,从加强经费政策宣贯力度、制定有针对性的管理办法、强化经费信息化管理、全面落实科研财务助理制度等四个方面提出优化建议,将科研经费“放管服”改革的各项政策落细、落准、落稳,从而有效提高科学基金项目经费使用效益。 展开更多
关键词 科研经费管理 改革实践 科学基金 “放管服”改革
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Metastatic status of sentinel lymph nodes in breast cancer determined with photoacoustic microscopy via dual-targeting nanoparticles 被引量:7
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作者 Yanfeng Dai Xiang Yu +5 位作者 Jianshuang Wei Fanxin Zeng yiran li Xiaoquan Yang Qingming Luo Zhihong Zhang 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期450-465,共16页
Detection of sentinel lymph nodes(SLNs)is critical to guide the treatment of breast cancer.However,distinguishing metastatic SLNs from normal and inflamed lymph nodes(LNs)during surgical resection remains a challenge.... Detection of sentinel lymph nodes(SLNs)is critical to guide the treatment of breast cancer.However,distinguishing metastatic SLNs from normal and inflamed lymph nodes(LNs)during surgical resection remains a challenge.Here,we report a CD44 and scavenger receptor class B1 dual-targeting hyaluronic acid nanoparticle(5K-HA-HPPS)loaded with the near-infra-red fluorescent dye DiR-BOA for SLN imaging in breast cancer.The small sized(~40 nm)self-assembled 5K-HA-HPPSs accumulated rapidly in the SLNs after intradermal injection.Compared with normal popliteal LNs(N-LN),there were ~3.2-fold and ~2.4-fold increases in fluorescence intensity in tumour metastatic SLNs(T-MLN)and inflamed LNs(Inf-LN),respectively,6 h after nanoparticle inoculation.More importantly,photoacoustic microscopy(PAM)of 5KHA-HPPS showed a significantly distinct distribution in T-MLN compared with N-LN and Inf-LN.Signals were mainly distributed at the centre of T-MLN but at the periphery of N-LN and Inf-LN.The ratio of PA intensity(R)at the centre of the LNs compared with that at the periphery was 5.93±0.75 for T-MLNs of the 5K-HA-HPPS group,which was much higher than that for the Inf-LNs(R=0.2±0.07)and N-LNs(R=0.45±0.09).These results suggest that 5K-HA-HPPS injection combined with PAM provides a powerful tool for distinguishing metastatic SLNs from pLNs and inflamed LNs,thus guiding the removal of SLNs during breast cancer surgery. 展开更多
关键词 BREAST INJECTION cancer
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