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An Automatic Implementation of Oropharyngeal Swab Sampling for Diagnosing Respiratory Infectious Diseases via Soft Robotic End-Effectors
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作者 Yafeng Cui Wenjie Yu +8 位作者 jingjing li Qi Shao Ding Weng Guoping Yin Xiaohao Zhang Xinjun liu Jingying Ye Jiadao Wang Huichan Zhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期55-67,共13页
The most widely adopted method for diagnosing respiratory infectious diseases is to conduct polymerase chain reaction(PCR)assays on patients’respiratory specimens,which are collected through either nasal or oropharyn... The most widely adopted method for diagnosing respiratory infectious diseases is to conduct polymerase chain reaction(PCR)assays on patients’respiratory specimens,which are collected through either nasal or oropharyngeal swabs.The manual swab sampling process poses a high risk to the examiner and may cause false-negative results owing to improper sampling.In this paper,we propose a pneumatically actuated soft end-effector specifically designed to achieve all of the tasks involved in swab sampling.The soft end-effector utilizes circumferential instability to ensure grasping stability,and exhibits several key properties,including high load-to-weight ratio,error tolerance,and variable swab-tip stiffness,leading to successful automatic robotic oropharyngeal swab sampling,from loosening and tightening the transport medium tube cap,holding the swab,and conducting sampling,to snapping off the swab tail and sterilizing itself.Using an industrial collaborative robotic arm,we integrated the soft end-effector,force sensor,camera,lights,and remote-control stick,and developed a robotic oropharyngeal swab sampling system.Using this swab sampling system,we conducted oropharyngeal swab-sampling tests on 20 volunteers.Our Digital PCR assay results(RNase P RNA gene absolute copy numbers for the samples)revealed that our system successfully collected sufficient numbers of cells from the pharyngeal wall for respiratory disease diagnosis.In summary,we have developed a pharyngeal swab-sampling system based on an“enveloping”soft actuator,studied the sampling process,and imple-mented whole-process robotic oropharyngeal swab-sampling. 展开更多
关键词 Diagnosis Medical robot Soft end-effector Swab-sampling Digital PCR
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The evolution and diurnal expression patterns of photosynthetic pathway genes of the invasive alien weed,Mikania micrantha
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作者 Kangkang Wang Mengjiao Jin +7 位作者 jingjing li Yesong Ren Zaiyuan li Xinghai Ren Cong Huang Fanghao Wan Wanqiang Qian Bo liu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期590-604,共15页
Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,includi... Mikania micrantha is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production.It has advantages in photosynthesis,including a similar net photosynthetic rate as C4 plants and a higher carbon fixation capacity.We used a combination of genomics and transcriptomics approaches to study the evolutionary mechanisms and circadian expression patterns of M.micrantha.In M.micrantha,16 positive selection genes focused on photoreaction and utilization of photoassimilates.In different tissues,98.1%of the genes associated with photoresponse had high expression in stems,and more than half of the genes of the C4 cycle had higher expression in stems than in leaves.In stomatal opening and closing,2 genes of carbonic anhydrase(CAs)had higher expression at 18:00 than at 8:00,and the slow anion channel 1(SLAC1)and high-leaf-temperature 1 kinase(HT1)genes were expressed at low levels at 18:00.In addition,genes associated with photosynthesis had higher expression levels at 7:00 and 17:00.We hypothesized that M.micrantha may undergo photosynthesis in the stem and flower organs and that some stomata of the leaves were opening at night by CO_(2)signals.In addition,its evolution may attenuate photoinhibition at high light intensities,and enhance more efficient of photosynthesis during low light intensity.And the tissue-specific photosynthetic types and different diurnal pattern of photosynthetic-related genes may contribute to its rapid colonization of new habitats of M.micrantha. 展开更多
关键词 invasion plant Mikania micrantha photosynthesis STOMATA stem
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Insights into the dwarfing mechanism of pear(Pyrus betulaefolia) based on anatomical and structural analysis using X-ray scanning
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作者 lili Dong Chuxuan Yang +6 位作者 Jing Wang jingjing li Mei Zhao Dingli li Zhiyun Qiu Chunhui Ma Zhenhua Cui 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期355-366,共12页
The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the p... The lack of a suitable rootstock to control scion growth has limited the development of high-density plantations in pear production, which is partly attributed to poor understanding of the dwarfing mechanism. In the present study, the rootstock of the dwarf-type pear (Pyrus betulaefolia)PY-9’ was identified and used as the material for anatomical analysis.PY-9’ grew to half the tree height of the normal cultivar Zhengdu’, along with fewer internodes and shorter length. Significant differences in growth rate betweenPY-9’ andZhengdu’ were detected at approximately 30 days after full bloom, which corresponded with the time of the greatest difference in water potential between the dwarf and normal cultivar.PY-9’ showed a higher photosynthetic rate thanZhengdu’. Anatomical analysis showed thatPY-9’ had higher area ratios of both phloem and xylem and more developed vascular tissues thanZhengdu’. The three-dimensional reconstructed skeleton of the xylem from X-ray computed tomography scanning revealed greater intervessel connectivity inZhengdu’ than inPY-9’, which could contribute to the more vigorous growth ofZhengdu’. This study thus provides the first comparison of the microstructural properties of xylem elements between a dwarfing-type and vigorous-type pear rootstock, providing new insights into the dwarfing mechanism in pear and facilitating breeding of dwarf pear rootstocks to increase crop productivity. 展开更多
关键词 Pyrus betulaefolia Anatomical analysis Dwarfing mechanism Intervessel connectivity ROOTSTOCK
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Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH_(2)/Nafion composite membranes
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作者 Xu li Dongwei Zhang +7 位作者 Si Chen Yingzhao Geng Yong liu libing Qian Xi Chen jingjing li Pengfei Fang Chunqing He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1734-1746,共13页
High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which ... High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which exhibits a superior proton conductivity.PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes.Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated.Significant enhancement in proton conduction for PCP-MCN around 55℃ is interestingly found due to the thermal motion of the PCP molecular chains.Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains,i.e.,the formation of substantial acid–base pairs(-SO_(3)^(-)…^(+)H–NH-),which further improves compatibility between additive and Nafion matrix.At the same humidity and temperature condition,the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion.Proton conductivity(σ)over wide ranges of humidities(30-100%RH at 25℃)and temperatures(30-98℃ at 100%RH)for prepared membranes is measured.The s in PCPMCN/Nafion composite membranes is remarkably enhanced,i.e.0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98℃ and 100%RH,because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation–deprotonation processes.The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN.In particular,when 3 wt.%PCP-MCN was added to Nafion,the power density of a single-cell fabricated with this composite membrane reaches impressively 0.480,1.098 W/cm^(2) under 40%RH,100%RH at 60℃,respectively,guaranteeing it to be a promising proton exchange membrane. 展开更多
关键词 Nafion composite membrane Surface-modified MIL-101-Cr-NH_(2) Proton conductivity Single-cell performance
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Spatiotemporal mapping of(ultra‐)mafic magmatic mine areas:Implications of economic and political realities in China
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作者 Heling li liang Tang +3 位作者 Tim T.Werner Zhengmeng Hou Fan Meng jingjing li 《Deep Underground Science and Engineering》 2024年第1期91-102,共12页
The spatiotemporal extension/expansion of mine areas is affected by multiple factors.So far,very little has been done to examine the interaction between mine areas and political or economic realities.The(ultra‐)mafic... The spatiotemporal extension/expansion of mine areas is affected by multiple factors.So far,very little has been done to examine the interaction between mine areas and political or economic realities.The(ultra‐)mafic magmatic mines in China played a specific role in supporting national development and providing an ideal research subject for monitoring their interrelationship.In this study,remote sensing and mining‐related GIS data were used to identify and analyze 1233(ultra‐)mafic magmatic mine area polygons in China,which covered approximately 322.96 km2 of land and included a V–Ti–Fe mine,a copper–nickel mine,a chromite mine,an asbestos mine,and a diamond mine.It was found that(1)the areal expansion of mines is significantly related to the mine types,perimeter,topography,and population density.(2)The mine area variation also reflects market and policy realities.The temporal expansion of the mine area from 2010 to 2020 followed an S‐shaped pattern(with the turning point occurring in 2014),closely related to iron overcapacity and tightened mining policies.(3)The complexity(D)of the mine area may reflect mine design and excavation practices.To be specific,lower D indicates early‐stage or artisanal/small‐scale mining,whereas higher D represents large‐scale mining.This study demonstrates that the detailed mapping of mine land can serve as an indicator to implement miningrelated market and policy changes.The(ultra‐)mafic mines area data set can be accessed at https://zenodo.org/record/7636616#.Y-p0uXaZOa0. 展开更多
关键词 complexity mine area mining and socioeconomic interaction spatiotemporal distribution (ultra‐)mafic magmatic mine
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Hetero Nucleus Growth Stabilizing Zinc Anode for High‑Biosecurity Zinc‑Ion Batteries 被引量:7
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作者 jingjing li Zhexuan liu +6 位作者 Shaohua Han Peng Zhou Bingan Lu Jianda Zhou Zhiyuan Zeng Zhizhao Chen Jiang Zhou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期349-360,共12页
Biocompatible devices are widely employed in modernized lives and medical fields in the forms of wearable and implantable devices,raising higher requirements on the battery biocompatibility,high safety,low cost,and ex... Biocompatible devices are widely employed in modernized lives and medical fields in the forms of wearable and implantable devices,raising higher requirements on the battery biocompatibility,high safety,low cost,and excellent electrochemical performance,which become the evaluation criteria toward developing feasible biocompatible batteries.Herein,through conducting the battery implantation tests and leakage scene simulations on New Zealand rabbits,zinc sulfate electrolyte is proved to exhibit higher biosecurity and turns out to be one of the ideal zinc salts for biocompatible zinc-ion batteries(ZIBs).Furthermore,in order to mitigate the notorious dendrite growth and hydrogen evolution in mildly acidic electrolyte as well as improve their operating stability,Sn hetero nucleus is introduced to stabilize the zinc anode,which not only facilitates the planar zinc deposition,but also contributes to higher hydrogen evolution overpotential.Finally,a long lifetime of 1500 h for the symmetrical cell,the specific capacity of 150 mAh g^(-1)under 0.5 A g^(-1)for the Zn-MnO_(2)battery and 212 mAh g^(-1)under 5 A g^(-1)for the Zn—NH4V4O10 battery are obtained.This work may provide unique perspectives on biocompatible ZIBs toward the biosecurity of their cell components. 展开更多
关键词 Aqueous zinc-ion batteries Biocompatible devices Operating stability Zinc anode Zinc salts electrolyte
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Investigation on step overcharge to self-heating behavior and mechanism analysis of lithium ion batteries 被引量:2
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作者 Fengling Yun Shiyang liu +14 位作者 Min Gao Xuanxuan Bi Weijia Zhao Zenghua Chang Minjuan Yuan jingjing li Xueling Shen Xiaopeng Qi ling Tang Yi Cui Yanyan Fang lihao Guo Shangqian Zhao Xiangjun Zhang Shigang Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期301-311,共11页
To obtain intrinsic overcharge boundary and investigate overcharge mechanism,here we propose an innovative method,the step overcharge test,to reduce the thermal crossover and distinguish the overcharge thermal behavio... To obtain intrinsic overcharge boundary and investigate overcharge mechanism,here we propose an innovative method,the step overcharge test,to reduce the thermal crossover and distinguish the overcharge thermal behavior,including 5%state of charge(SOC)with small current overcharge and resting until the temperature equilibrium under adiabatic conditions.The intrinsic thermal response and the self-excitation behaviour are analysed through temperature and voltage changes during the step overcharge period.Experimental results show that the deintercalated state of the cathode is highly correlated to self-heating parasitic reactions.Before reaching the upper limit of Negative/Positive(N/P)ratio,the temperature changes little,the heat generation is significantly induced by the reversible heat(endothermic)and ohmic heat,which could balance each other.Following that the lithium metal is gradually deposited on the surface of the anode and reacts with electrolyte upon overcharge,inducing selfheating side reaction.However,this spontaneous thermal reaction could be“self-extinguished”.When the lithium in cathode is completely deintercalated,the boundary point of overcharge is about 4.7 V(~148%SOC,>40℃),and from this point,the self-heating behaviour could be continuously triggered until thermal runaway(TR)without additional overcharge.The whole static and spontaneous process lasts for 115 h and the side reaction heat is beyond 320,000 J.The continuous self-excitation behavior inside the battery is attributed to the interaction between the highly oxidized cathode and the solvent,which leads to the dissolution of metal ions.The dissolved metal ions destroy the SEI(solid electrolyte interphase)film on the surface of the deposited Li of anode,which induces the thermal reaction between lithium metal and the solvent.The interaction between cathode,the deposited Li of anode,and solvent promotes the temperature of the battery to rise slowly.When the temperature of the battery reaches more than 60℃,the reaction between lithium metal and solvent is accelerated.After the temperature rises rapidly to the melting point of the separator,it triggers the thermal runaway of the battery due to the short circuit of the battery. 展开更多
关键词 Lithium ion battery Step overcharge SELF-HEATING Boundary Heat generation Amount of lithium
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算法透明何以提升公众的政府信任? 被引量:1
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作者 樊博 李晶晶 《公共行政评论》 CSSCI 北大核心 2024年第1期4-24,M0003,共22页
随着算法辅助决策逐渐嵌入公共部门,算法黑箱极易冲击公众对于政府公权力的信任。算法透明成为政府治理的应有之义。然而,算法透明何以实现,以及政府信任与算法透明的关联仍存在争议。论文基于“金税工程”税务算法现实案例,设计了一个... 随着算法辅助决策逐渐嵌入公共部门,算法黑箱极易冲击公众对于政府公权力的信任。算法透明成为政府治理的应有之义。然而,算法透明何以实现,以及政府信任与算法透明的关联仍存在争议。论文基于“金税工程”税务算法现实案例,设计了一个情景调查实验,实证检验了算法透明的实现机制及其对政府信任的影响路径。研究发现:(1)算法过程透明、算法结果透明均对公众感知算法透明具有显著正向影响;(2)感知算法透明能够提高公众对政府的信任;(3)算法信任在感知算法透明、政府信任中发挥了部分中介效应。研究明晰了算法透明的概念,回应了算法透明与信任的迷思,并阐明了其中的强化机制,为推进算法善治提供了实践参考。 展开更多
关键词 算法透明 政府信任 算法信任 调查实验
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The Effect of Case Management for Schizophrenia Clients in China
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作者 Jia Cheng Huaicun liu +6 位作者 Tong Geng Yong Wang ling Yu jingjing li Wenxiu li Caili Chen Guizhong Yao 《Journal of Behavioral and Brain Science》 2020年第8期297-310,共14页
<strong>Background</strong>: The aim at this study is to establish the effectiveness of case management (CM) compared to care as usual (CAU) in patients with schizophrenia. <strong>Methods</strong... <strong>Background</strong>: The aim at this study is to establish the effectiveness of case management (CM) compared to care as usual (CAU) in patients with schizophrenia. <strong>Methods</strong>: 128 patients with schizophrenia were recruited from the community of Haidian District (Beijing, China), 68 patients in the CM group and 60 patients in the CAU group. Efficacy and safety information were assessed at one year follow-up. The relapse rate was similar in both groups after 12 months followed up (7% and 5%). The withdraw rate was significant lower in CM group compared with CAU group (10% and 36%). <strong>Results</strong>: There is no significant difference in PANSS, PSP and SSMI score between 2 groups at each visit. Between endpoint and baseline, there is a significant improvement on PANSS negative score and PSP in patients treated with CM, while CAU group was not significantly changed. <strong>Conclusions</strong>: There is a possible effectiveness of CM group of improving negative symptoms and social function in schizophrenia clients. 展开更多
关键词 Case Management Care as Usual Schizophrenia Clients PANSS Score
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RNA sequencing of exosomes secreted by fibroblast and Schwann cells elucidates mechanisms underlying peripheral nerve regeneration 被引量:1
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作者 Xinyang Zhou Yehua Lv +8 位作者 Huimin Xie Yan li Chang liu Mengru Zheng Ronghua Wu Songlin Zhou Xiaosong Gu jingjing li Daguo Mi 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1812-1821,共10页
Exosomes exhibit complex biological functions and mediate a variety of biological processes,such as promoting axonal regeneration and functional recove ry after injury.Long non-coding RNAs(IncRNAs)have been reported t... Exosomes exhibit complex biological functions and mediate a variety of biological processes,such as promoting axonal regeneration and functional recove ry after injury.Long non-coding RNAs(IncRNAs)have been reported to play a crucial role in axonal regeneration.Howeve r,the role of the IncRNA-microRNAmessenger RNA(mRNA)-competitive endogenous RNA(ceRNA)network in exosome-mediated axonal regeneration remains unclear.In this study,we performed RNA transcriptome sequencing analysis to assess mRNA expression patterns in exosomes produced by cultured fibroblasts(FC-EXOs)and Schwann cells(SCEXOs).Diffe rential gene expression analysis,Gene Ontology analysis,Kyoto Encyclopedia of Genes and Genomes analysis,and protein-protein intera ction network analysis were used to explo re the functions and related pathways of RNAs isolated from FC-EXOs and SC-EXOs.We found that the ribosome-related central gene Rps5 was enriched in FC-EXOs and SC-EXOs,which suggests that it may promote axonal regeneration.In addition,using the miRWalk and Starbase prediction databases,we constructed a regulatory network of ceRNAs targeting Rps5,including 27 microRNAs and five IncRNAs.The ceRNA regulatory network,which included Ftx and Miat,revealed that exsosome-derived Rps5 inhibits scar formation and promotes axonal regeneration and functional recovery after nerve injury.Our findings suggest that exosomes derived from fibro blast and Schwann cells could be used to treat injuries of peripheral nervous system. 展开更多
关键词 ceRNA network EXOSOMES fibroblast cells Gene Ontology(GO) Kyoto Encyclopedia of Genes and Genomes(KEGG) protein-protein interaction(PPI)networks RNA-seq Schwann cells
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标准化二氧化碳还原反应中的同位素溯源方法
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作者 李晶晶 姜淑娟 宋少青 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第4期1-3,共3页
自工业革命以来,二氧化碳(CO_(2))排放量迅速增加.将二氧化碳通过催化反应转化为高附加值产物,被认为是重要的减污降碳策略.然而,由于CO_(2)还原反应产物的多样性以及催化剂制备过程中可能残留的有机物质,导致难以准确评估催化剂的真实... 自工业革命以来,二氧化碳(CO_(2))排放量迅速增加.将二氧化碳通过催化反应转化为高附加值产物,被认为是重要的减污降碳策略.然而,由于CO_(2)还原反应产物的多样性以及催化剂制备过程中可能残留的有机物质,导致难以准确评估催化剂的真实活性.尽管13CO_(2)同位素溯源技术已被广泛用于确定还原产物的碳源,但其严谨性不足可能导致溯源结果失真,影响了CO_(2)还原领域的发展.为了解决CO_(2)还原反应中催化剂活性评估的难题,汪圣尧等深入研究了同位素示踪原理,提出标准化同位素追溯新方法(Nat.Commun.,2023,14,2534).尽管气-质谱联用技术被视为普适方法,但现有方法难以充分分离复杂混合气体样品,因此需要谨慎对待溯源结果.13C-NMR光谱法常用于液体产物示踪,但由于自然界中存在13C同位素,这在一定程度上影响了同位素示踪技术的精确性.而1H-NMR因能识别与13C同位素相关的氢原子的特征分裂模式,而成为一种可行的替代方案.研究指出,同位素追踪在CO_(2)减排中的应用复杂,需要选择合适的气相色谱条件实现产物的有效分离,以确保溯源结果的可靠性.该研究还建立了同位素溯源检测的标准方法,并提供了同位素标记物的质谱指纹图谱.对于理解同位素溯源过程和推动CO_(2)还原研究具有重要意义.综上,对于CO_(2)还原反应潜在产物的溯源研究已成为衡量催化剂真实性能的关键指标之一.文章提出的标准化同位素溯源方法可作为该领域研究的可靠标准,并为实现真实可靠的CO_(2)还原反应提供有力保障. 展开更多
关键词 CO_(2)还原 同位素溯源 标准化 气-质联用技术 方法
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VLBI with SKA:Possible Arrays and Astrometric Science
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作者 Yingjie li Ye Xu +4 位作者 jingjing li Shuaibo Bian Zehao lin Chaojie Hao Dejian liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第7期1-33,共33页
The next generation of very long baseline interferometry(VLBI)is stepping into the era of microarcsecond(μas)astronomy,and pushing astronomy,especially astrometry,to new heights.VLBI with the Square Kilometre Array(S... The next generation of very long baseline interferometry(VLBI)is stepping into the era of microarcsecond(μas)astronomy,and pushing astronomy,especially astrometry,to new heights.VLBI with the Square Kilometre Array(SKA),SKA-VLBI,will increase current sensitivity by an order of magnitude,and reach astrometric precision routinely below 10μas,even challenging 1μas.This advancement allows precise parallax and proper motion measurements of various celestial objects.Such improvements can be used to study objects(including isolated objects,and binary or multiple systems)in different stellar stages(such as star formation,main-sequence stars,asymptotic giant branch stars,pulsars,black holes,white dwarfs,etc.),unveil the structure and evolution of complex systems(such as the Milky Way),benchmark the international celestial reference frame,and reveal cosmic expansion.Furthermore,the theory of general relativity can also be tested with SKA-VLBI using precise measurements of light deflection under the gravitational fields of different solar system objects and the perihelion precession of solar system objects. 展开更多
关键词 astrometry-parallaxes-stars kinematics and dynamics-ISM kinematics and dynamics-Galaxy kinematics and dynamics-galaxies kinematics and dynamics-gravitation
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Flavonoid extracts from chrysanthemum with appropriate anthocyanins turn blue when exposed to iron ions
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作者 Yanfei li Jiaying Wang +8 位作者 Chenfei Lu Zhongman Wang Chengyan Deng Kang Gao jingjing li Zhijun Fang Hao liu Yan Hong Silan Dai 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期837-852,共16页
Although some species that accumulate only cyanidin(Cy)in nature can produce blue flowers through iron ions,there has been no evidence of blue chrysanthemums being generated in this manner.This study revealed that fla... Although some species that accumulate only cyanidin(Cy)in nature can produce blue flowers through iron ions,there has been no evidence of blue chrysanthemums being generated in this manner.This study revealed that flavonoid extracts from the ray florets of the chrysanthemum cultivar‘Wandai Fengguang’turned blue when exposed to Fe^(3+).Samples that could turn blue were labeled as CB(Cy-determined blue flowers),while samples that did not turn blue were labeled as CN(Cy-determined non-blue flowers).After a series of experiments,a stable screening system was established using flavonoid extracts containing NaAc buffer at pH 5.5 and a total anthocyanin concentration(TAC)of 30 μmol·L^(-1),and the addition of Fe^(3+)from 0 to 0.25 μmol·L^(-1)allowed for the selection of five CB samples from 39 chrysanthemum cultivars.All five CB samples exhibited flower color phenotypes that belonged to Cluster-I with redness(a*)values ranging from 29.03 to 45.99,yellowness(b*)values from-11.31 to 3.77,and brightness(L*)values from 29.07 to 45.99.Additionally,the ratio of TAC to total luteolin concentration(TLC)was found to be a critical factor for distinguishing between CB and CN samples.To realize the desired blue hue in the flavonoid extracts with the participation of Fe^(3+),a TAC to TLC ratio of 2.25 and above is required.Moreover,the protoplasts and ray florets of CB samples that turned blue with the involvement of Fe^(2+)showed great potential for cultivating blue chrysanthemums through ferric-anthocyanin chelate.Overall,this study reveals that blue flowers can be cultivated through the increase in the iron ion concentration,combined with the accumulation of Cy. 展开更多
关键词 Chrysanthemum×morifolium CYANIDIN Copigment Ferric-anthocyanin chelate Blue flower
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Structural characterization and prebiotic potential of polysaccharides from Polygonatum sibiricum
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作者 Zihan Qi Tiexiang Gao +5 位作者 jingjing li Shuhan Zhou Zhigang Zhang Mingzhu Yin Haiming Hu Hongtao liu 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期2208-2220,共13页
Polygonatum sibiricum has been widely used due to its excellent biological activities.We prepared a novel polysaccharide from P.sibiricum(PSP)in this study.According a monosaccharide composition analysis,PSP was mainl... Polygonatum sibiricum has been widely used due to its excellent biological activities.We prepared a novel polysaccharide from P.sibiricum(PSP)in this study.According a monosaccharide composition analysis,PSP was mainly composed of fructose and glucose with a molar percentage of 93.81:5.12.The main linkage types were identified asα-D-Glcp-1→and→2-β-D-Fruf-1→.The molecular weight of PSP showed no significant change after simulated salivary and gastrointestinal digestion.However,PSP could be broken down by intestinal bacteria.Our findings revealed that PSP administration increased the abundance of probiotics such as Bifidobacterium.Furthermore,the results showed that gut microbes could utilize PSP to produce short-chain fatty acids including acetic acid,propionic acid,and butyric acid.Also,the PSP fermentation broth displayed an excellent scavenging effect on free radicals,including 2,2-diphenyl-1-picrylhydrazyl radical,superoxide radical,and hydroxyl radical.In summary,this study will help to promote the application of PSP as prebiotics in functional food and the medical industry. 展开更多
关键词 Dietary polysaccharides Prebiotic Gut microbiota Short-chain fatty acids
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Research Progress of Aromatic Bed Curtains for Aiding Sleep Based on Lavender Microcapsule Technique
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作者 Xiaojun LUO Xuan PAN +3 位作者 Kaiyan QIU Ken HUANG Yao LU jingjing li 《Agricultural Biotechnology》 2024年第2期64-67,71,共5页
In this paper, the preparation technique of lavender essential oil microcapsules and the construction method of aromatic textiles were expounded, and the research status of bed curtains and lavender microcapsules at h... In this paper, the preparation technique of lavender essential oil microcapsules and the construction method of aromatic textiles were expounded, and the research status of bed curtains and lavender microcapsules at home and abroad was analyzed and studied from the perspective of application in textiles. The application of lavender essential oil to bed curtains through the microcapsule technique was put forward to allow lavender essential oil to play its role of helping sleep in bed curtains. This paper expounded the material selection and preparation technique of lavender microcapsule agents, and put forward the preparation method of microcapsules with mixed solutions of pure Chinese medicine extracts and natural essences as core material and high-viscosity epoxy resin as wall materials. The post-processing techniques and the spray ironing method for clothing were studied and developed, and these techniques and methods were applied to bed curtains, and good results were obtained. 展开更多
关键词 LAVENDER Sleep aid Aromatic bed curtain MICROCAPSULE
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Temperature field calculation of rail flash welding
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作者 Rui Xu Min Zhang +6 位作者 Zhenkun Gao Guo Zhao Wei Ding Shouming Wang Peng Zhang Xiang liu jingjing li 《High-Speed Railway》 2024年第2期116-121,共6页
The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,t... The forging stage of rail flash welding has a decisive influence on joint strength,and the study of the temperature distribution in the process has an important role in further improving joint strength.In this paper,three calculation methods for the temperature field are given.First,the finite element model of the temperature field before forging rail flash welding is established by using the transient heat module of Ansys software and verified by infrared temperature measurement.Second,the temperature distribution of different parts of the rail before flash welding is obtained by using infrared thermal imaging equipment.Third,Matlab software is used to calculate the temperature of the non-measured part.Finally,the temperature distribution function along the rail axis is fitted through the temperature measurement data.The temperature distribution before the top forging of the rail flash welding can be used to analyze the joint and heat-affected zone organization and properties effectively and to guide the parameter setting and industrial production. 展开更多
关键词 Flash welding Temperature field Joint strength Software calculation
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A pH-sensitive supramolecular nanosystem with chlorin e6 and triptolide co-delivery for chemo-photodynamic combination therapy 被引量:5
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作者 Yihan Wu jingjing li +9 位作者 Xuemei Zhong Jinfeng Shi Yanfen Cheng Chenglin He Jiaxin li liang Zou Chaomei Fu Meiwan Chen Jinming Zhang Huile Gao 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第2期206-218,共13页
The combination of Ce6,an acknowledged photosensitizer,and TPL,a natural anticancer agent,has been demonstrated as a useful strategy to reinforce the tumor growth suppression,as well as decrease the systemic side effe... The combination of Ce6,an acknowledged photosensitizer,and TPL,a natural anticancer agent,has been demonstrated as a useful strategy to reinforce the tumor growth suppression,as well as decrease the systemic side effects compared with their monotherapy.However,in view of the optimal chemo-photodynamic combination efficiency,there is still short of the feasible nanovehicle to steadily co-deliver Ce6 and TPL,and stimuli-responsively burst release drugs in tumor site.Herein,we described the synergistic antitumor performance of a pH-sensitive supramolecular nanosystem,mediated by the host–guest complexing betweenβ-CD and acid pH-responsive amphiphilic co-polymer mPEG-PBAE-mPEG,showing the shell–core structural micelles with the tightβ-CD layer coating.Both Ce6 and TPLwere facilely co-loaded into the spherical supramolecular NPs(TPL+Ce6/NPs)by one-step nanoprecipitation method,with an ideal particle size(156.0 nm),acid pH-responsive drug release profile,and enhanced cellular internalization capacity.In view of the combination benefit of photodynamic therapy and chemotherapy,as well as co-encapsulation in the fabricated pH-sensitive supramolecular NPs,TPL+Ce6/NPs exhibited significant efficacy to suppress cellular proliferation,boost ROS level,lower MMP,and promote cellular apoptosis in vitro.Particularly,fluorescence imaging revealed that TPL+Ce6/NPs preferentially accumulated in the tumor tissue area,with higher intensity than that of free Ce6.As expected,upon 650-nm laser irradiation,TPL+Ce6/NPs exhibited a cascade of amplified synergistic chemo-photodynamic therapeutic benefits to suppress tumor progression in both hepatoma H22 tumor-bearingmice and B16 tumor-bearingmice.More importantly,lower systemic toxicitywas found in the tumor-bearingmice treated with TPL+Ce6/NPs.Overall,the designed supramolecular TPL+Ce6/NPs provided a promising alternative approach for chemo-photodynamic therapy in tumor treatment. 展开更多
关键词 TRIPTOLIDE Chemo-photodynamic pH-sensitive supramolecular Nanosystem CO-DELIVERY
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MiR-214-3p promotes proliferation and inhibits estradiol synthesis in porcine granulosa cells 被引量:5
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作者 Shengjie Shi Xiaoge Zhou +5 位作者 jingjing li Lutong Zhang Yamei Hu Yankun li Gongshe Yang Guiyan Chu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2021年第1期185-197,共13页
Background: Granulosa cells(GCs) proliferation and estradiol synthesis significantly affect follicular development.The miR-214-3p expression in the ovarian tissues of high-yielding sows is higher than that in low-yiel... Background: Granulosa cells(GCs) proliferation and estradiol synthesis significantly affect follicular development.The miR-214-3p expression in the ovarian tissues of high-yielding sows is higher than that in low-yielding sows,indicating that miR-214-3p may be involved in sow fertility. However, the functions and mechanisms of miR-214-3p on GCs are unclear. This study focuses on miR-214-3p in terms of the effects on GCs proliferation and estradiol synthesis.Results: Our findings revealed that miR-214-3p promotes proliferation and inhibits estradiol synthesis in porcine GCs. MiR-214-3p can increase the percentage of S-phase cells, the number of EdU labeled positive cells, and cell viability. However, E2 concentration was reduced after miR-214-3p agomir treatment. We also found that miR-214-3p up-regulates the expression of cell cycle genes including cell cycle protein B(Cyclin B), cell cycle protein D(Cyclin D), cell cycle protein E(Cyclin E), and cyclin-dependent kinase 4(CDK4) at the transcription and translation levels, but down-regulates the mRNA and protein levels of cytochrome P450 family 11 subfamily A member 1(CYP11A1), cytochrome P450 family 19 subfamily A member 1(CYP19A1), and steroidogenic acute regulatory protein(StAR)(i.e., the key enzymes in estradiol synthesis). On-line prediction, bioinformatics analysis, a luciferase reporter assay, RT-qPCR, and Western blot results showed that the target genes of miR-214-3p in proliferation and estradiol synthesis are Mfn2 and NR5A1, respectively.Conclusions: Our findings suggest that miR-214-3 p plays an important role in the functional regulation of porcine GCs and therefore may be a target gene for regulating follicular development. 展开更多
关键词 Estradiol synthesis Granulosa cells MiR-214-3p PROLIFERATION
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Hierarchical structured CoP nanosheets/carbon nanofibers bifunctional eletrocatalyst for high-efficient overall water splitting 被引量:3
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作者 Xiao-Qiao Xie Junpeng liu +3 位作者 Chaonan Gu jingjing li Yan Zhao Chun-Sen liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第1期503-510,I0013,共9页
The design of efficient,stable,and economical electrocatalysts for oxygen and hydrogen evolution reaction(OER and HER)is a major challenge for overall water splitting.Herein,a hierarchical structured CoP/carbon nanofi... The design of efficient,stable,and economical electrocatalysts for oxygen and hydrogen evolution reaction(OER and HER)is a major challenge for overall water splitting.Herein,a hierarchical structured CoP/carbon nanofibers(CNFs)composite was successfully synthesized and its potential application as a high-efficiency bifunctional electrocatalyst for overall splitting water was evaluated.The synergetic effect of two-dimensional(2D)CoP nanosheets and on e-dimensi on al(1D)CNFs endowed the CoP/CNFs composites with abundant active sites and rapid electron and mass transport pathways,and thereby significantly improved the electrocatalytic performances.The optimized CoP/CNFs delivered a current density of 10 mA cm^(-2) at low overpotential of 325 mV for OER and 225 mV for HER.In the overall water splitting,CoP/CNFs achieved a low potential of 1.65 V at 10 mA cm^(-2).The facile strategy provided in the present work can facilitate the design and development of multifunctional non-noble metal catalysts for energy applications. 展开更多
关键词 Bifunctional electrocatalyst Overall splitting water Electrospun carbon nanofibers CoP nanosheets Non-noble metal catalysts
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Comparison of the photo-acclimation potential of fl oating and benthic thalli of Sargassum horneri(Phaeophyta)during autumn and winter 被引量:1
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作者 jingjing li Yunlong PANG +4 位作者 Song QIN Zhengyi liU Zhihai ZHONG Wanlin SONG Longchuan ZHUANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第1期195-205,共11页
Sargassum horneri is a foundational species and an important contributor to the fl oating seaweed stock along the northeastern coast of Asia.In this study,benthic and fl oating thalli of S.horneri were collected from ... Sargassum horneri is a foundational species and an important contributor to the fl oating seaweed stock along the northeastern coast of Asia.In this study,benthic and fl oating thalli of S.horneri were collected from Changdao Island(37°54′N,120°43′E),Bohai Bay,China.We conducted an in-situ and an indoor experiment to study the acclimation potential in S.horneri to abiotic conditions at sea surface in autumn and winter.Both benthic and fl oating thalli were cultured in situ for two months(from October to December)at diff erent depths:0 m above sea level(masl)and 3 m below sea level(mbsl),and their growth rate,biochemical content,and photosynthetic performance were compared.During the fi rst month of culture,the relative growth rate of fl oating thalli was 2-fold greater than that of benthic thalli at 0 masl.The photosynthetic rate of most thalli was signifi cantly higher at 0 masl than at 3 mbsl.In the indoor experiments,fl oating and benthic thalli were exposed to high light intensity(400μmol photons/(m^(2)·s)photosynthetically active radiation(PAR))for 21 d,and their photo-acclimation capacities were compared.Under high light intensity,the two types of thalli showed low maximum quantum yield(F_(v)/F_(m))and light utilisation effi ciency(α)but high light saturation point(E_(k)).Floating thalli showed higher photosynthetic rate and photoprotective ability than benthic thalli at high light intensity.The eff ective quantum yield of photosystem II[Y(II)]of both types of thalli recovered after a 6-day treatment with low light intensity(40μmol photons/(m^(2)·s)).These fi ndings suggest that S.horneri is highly acclimated to the sea surface environment,which possibly contributes to its rapid accumulation and long free-fl oating periods at the sea surface. 展开更多
关键词 chlorophyll-a fl uorescence growth photosynthesis photosynthetic pigments Sargassum horneri
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