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PcUGT84A82 catalyzes a key step in the biosynthesis of galloylated macrocyclic polyphenols in Penthorum chinense Pursh 被引量:1
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作者 Yajing Li Yiru Liu +11 位作者 Xiao Li Ke Zhang Yun Wang Minghui Lu Xu Yang Yinan Zou Jiajia Cao Lianna Sun junfeng chen Doudou Huang Wansheng chen Ying Xiao 《The Crop Journal》 2026年第1期247-254,共8页
Penthorum chinense Pursh has been used for centuries as an herbal medicine and food in East Asia.The main active substances in P.chinense are galloylated macrocyclic polyphenolic compounds,which have excellent medicin... Penthorum chinense Pursh has been used for centuries as an herbal medicine and food in East Asia.The main active substances in P.chinense are galloylated macrocyclic polyphenolic compounds,which have excellent medicinal properties.Galloylation and glycosylation are key steps in the formation of polyphenolic compounds,as the glycosylation of flavonoids is required for the acylation of flavonoid glycosides,and the glycosylation of gallic acid is necessary for its role as an acyl donor.Therefore,glycosylation to generate the acyl donor or acceptor is a core step in the biosynthesis of polyphenolic compounds.However,how this glycosylation occurs in P.chinense is unknown.In this study,we determined that the UDP-glucose transferase PcUGT84A82 mediates the glycosylation of gallic acid and pinocembrin to produce 1-O-Galloyl-β-D-glucose and pinocembroside,respectively.Metabolic profiling of polyphenolic compounds using UHPLC-ESI–Q-TOF/MS revealed high levels of polyphenols in flowers,leaves,and roots,and low levels in stems of P.chinense.We performed isoform-sequencing(Iso-seq)to assemble a full-length transcriptome of P.chinense,from which we identified 58 UGT family members.PcUGT84A82 is highly similar to functional UGTs in other plant species,and PcUGT84A82 transcript levels were positively correlated with the levels of various polyphenolic compounds.We validated the function of PcUGT84A82 via in vitro enzyme assays and transient expression in Nicotiana benthamiana leaves.Subcellular localization tests showed that PcUGT84A82 localizes to the nucleus and cytoplasm.In summary,PcUGT84A82 catalyzes the conversion of gallic acid to 1-O-Galloyl-β-D-glucose as the acyl donor and pinocembrin to pinocembroside as the acyl acceptor,mediating the biosynthesis of galloylated macrocyclic polyphenolic compounds in P.chinense.These findings lay the foundation for elucidating the entire biosynthetic pathway of active polyphenols in this important herbal plant species. 展开更多
关键词 POLYPHENOL Penthorum chinense Pursh UGT84A82 1-O-Galloyl-β-D-glucose Gallic acid
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乏情和发情初产母猪下丘脑–垂体–卵巢轴中lincRNAs表达谱比较分析 被引量:3
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作者 任巧玲 张家庆 +7 位作者 陆东锋 王璟 陈俊峰 马强 白献晓 郭红霞 高彬文 邢宝松 《遗传》 CAS CSCD 北大核心 2020年第4期388-402,共15页
初产母猪断奶后能否正常发情对养猪生产影响重大,也是初产母猪被淘汰的主要原因。本研究以乏情和发情初产母猪为研究对象,首次利用RNA-seq技术对其下丘脑-垂体-卵巢轴中的基因间长链非编码RNAs(long intergenic noncoding RNAs,lincRNAs... 初产母猪断奶后能否正常发情对养猪生产影响重大,也是初产母猪被淘汰的主要原因。本研究以乏情和发情初产母猪为研究对象,首次利用RNA-seq技术对其下丘脑-垂体-卵巢轴中的基因间长链非编码RNAs(long intergenic noncoding RNAs,lincRNAs)进行筛选比较,得到lincRNAs的表达图谱,并对其特征和功能进行了初步分析。结果显示,在乏情和发情初产母猪下丘脑–垂体–卵巢轴中鉴定得到3519个lincRNAs,以发情组为对照共有17个lincRNAs存在差异表达,其中12个表达上调,5个表达下调(FC≥2,P<0.05)。选择4个差异表达的lincRNAs经qRT-PCR验证,其表达水平与测序结果基本一致。对这17个差异表达的lincRNAs进行GO分析、KEGG通路分析及lincRNA-mRNA共表达网络分析,发现这些lincRNAs主要与猪卵母细胞减数分裂成熟、卵巢细胞分化及颗粒细胞凋亡等生殖活动相关。本研究结果丰富了猪lincRNAs数据资源,为进一步深入研究初产母猪的生殖机能提供了理论依据。 展开更多
关键词 lincRNAs 乏情 发情 初产母猪 下丘脑–垂体–卵巢轴
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去势和非去势公猪背最长肌circRNA差异表达分析 被引量:3
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作者 邢宝松 王璟 +7 位作者 陈俊峰 马强 任巧玲 张家庆 张华 滑留帅 孙加节 曹海 《遗传》 CAS CSCD 北大核心 2021年第11期1066-1077,共12页
公猪去势可减少异味和打斗,但去势后产肉量和肌内脂肪沉积发生变化,其分子机制的解析对生产具有重要意义。近年来研究表明,环状RNA(circRNA)在肌肉发育中具有重要调控作用。为探究去势后circRNAs对背最长肌发育的调控,本研究选择6头淮... 公猪去势可减少异味和打斗,但去势后产肉量和肌内脂肪沉积发生变化,其分子机制的解析对生产具有重要意义。近年来研究表明,环状RNA(circRNA)在肌肉发育中具有重要调控作用。为探究去势后circRNAs对背最长肌发育的调控,本研究选择6头淮南公猪,随机选择3头去势,当体重达130 kg左右屠宰,采集背最长肌样品,利用高通量测序筛选差异表达circRNAs(differentially expressed circRNAs,DECs)并进行KEGG功能富集分析。结合前期筛选的公猪去势相关miRNAs,构建DECs-miRNAs调控网络,最后使用猪骨骼肌卫星细胞验证候选circRNA表达谱及其与miRNA互作关系。结果表明,去势和非去势组背最长肌样品共获得5866个circRNAs,两组之间共有370个DECs(|log2Foldchange|>1,padj<0.8),KEGG富集分析表明,DECs来源母基因主要富集于肌肉发育、肌纤维类型转化、能量代谢等相关通路。构建的DECs-miRNA调控网络共包括69个circRNAs和8个miRNAs。选择circRNA_2241和circRNA_4237进行验证,结果发现这两个circRNAs真实存在且表达趋势与测序结果一致。进一步在猪骨骼肌卫星细胞初步验证circRNA_2241与miR-1互作关系,结果表明睾酮显著促进circRNA_2241表达,同时抑制miR-1表达。本研究结果提示circRNAs可能通过与miRNAs互作调控猪去势后背最长肌发育,从而为解析去势对肌肉发育调控的分子机制提供参考。 展开更多
关键词 环状RNA 去势 公猪 背最长肌
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Establishment of rat model for aspiration pneumonia and potential mechanisms
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作者 Hanbing Hu junfeng chen +5 位作者 Yiru Shao Yuedong Tang Yu Dun Obulkasim Memet Xuanrong Bao Jie Shen 《Animal Models and Experimental Medicine》 2025年第6期1105-1118,共14页
Background:Aspiration pneumonia is a severe health concern,particularly for ICU patients with impaired airway defenses.Current animal models fail to fully replicate the condition,focusing solely on chemical lung injur... Background:Aspiration pneumonia is a severe health concern,particularly for ICU patients with impaired airway defenses.Current animal models fail to fully replicate the condition,focusing solely on chemical lung injury from gastric acid while neglecting pathogen-induced inflammation.This gap hinders research on pathogenesis and treatment,creating an urgent need for a clinically relevant model.This study aimed to develop an improved rat model of aspiration pneumonia by combining hydrochloric acid(HCl)and lipopolysaccharide(LPS)administration.Methods:Specific pathogen-free Sprague Dawley rats underwent intratracheal instillation of HCl and LPS.Techniques included rat weight measurement,tracheal intubation,pulmonary function monitoring,lung tissue sampling with HE staining and scoring,bronchoalveolar lavage fluid(BALF)sampling,protein and inflammatory cytokine analysis via BCA and ELISA,BALF pH determination,Evans Blue dye assessment,blood gas analysis,FITC-dextran leakage,Western blotting,electron microscopy,survival analysis,and transcriptome sequencing with bioinformatics.Statistical analysis was performed using GraphPad Prism.Results:The optimal model involved instillation of 1.5μL/g.wt HCl(pH=1)followed by 20μg/g.wt LPS after 1 h.This model reproduced acute lung injury,including tissue damage,pulmonary microvascular dysfunction,inflammatory responses,hypoxemia,and impaired pulmonary ventilation,with recovery observed at 72 h.PANoptosis was confirmed,characterized by increased markers.Concentration-dependent effects of HCl and LPS on lung damage were identified,alongside cytokine elevation and microvascular dysfunction.Conclusions:This optimized model closely mimics clinical aspiration pneumonia,providing a valuable tool for studying pathophysiology and therapeutic strategies. 展开更多
关键词 acute lung injury ASPIRATION disease models PNEUMONIA
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All-microwave CZ gate based on fixed-frequency driven coupler
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作者 Wanpeng Gao Xiaoliang He +5 位作者 Zhengqi Niu Daqiang Bao Kuang Liu junfeng chen Zhen Wang Z.R.Lin 《Chinese Physics B》 2025年第4期201-205,共5页
High-quality entangling gates are crucial for scalable quantum information processing.Implementing all-microwave two-qubit gates on fixed-frequency transmons offers advantages in reducing wiring complexity,but the gat... High-quality entangling gates are crucial for scalable quantum information processing.Implementing all-microwave two-qubit gates on fixed-frequency transmons offers advantages in reducing wiring complexity,but the gate performance is often limited due to the residual ZZ interaction and the frequency crowding problem.Here,we introduce a novel scheme that enables a microwave drive-activated CZ gate compatible with the coupler structure to suppress the residual ZZ interaction.The microwave drive is applied to the coupler and the microwave drive frequency remains far detuned from the system’s transition frequency to alleviate the frequency crowding problem.We model the gate process analytically and demonstrate a theoretical gate fidelity up to 99.9%numerically.Our scheme is compatible with current coupler-structure-based circuits,and insensitive to microwave crosstalk,showing a possible path for all-microwave quantum operations at scale. 展开更多
关键词 quantum computing superconducting qubit two-qubit gate
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我国亚洲象保护与农村社区发展协同问题分析 被引量:7
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作者 张忠义 胡宇轩 +3 位作者 陈俊峰 萧嘉豪 王傲雪 谢屹 《世界林业研究》 CSCD 北大核心 2022年第3期106-111,共6页
亚洲象保护与农村社区发展的协同共进关系到所在区域能否实现人与自然和谐发展。文中首先基于协同理论分析亚洲象所在区域的社会生态系统特征,建立了亚洲象保护与社区发展的交互作用分析框架;其次,分析亚洲象保护与社区发展的交互作用,... 亚洲象保护与农村社区发展的协同共进关系到所在区域能否实现人与自然和谐发展。文中首先基于协同理论分析亚洲象所在区域的社会生态系统特征,建立了亚洲象保护与社区发展的交互作用分析框架;其次,分析亚洲象保护与社区发展的交互作用,得出亚洲象所在区域的社会生态系统存在协同问题;再次,从亚洲象对应的生态子系统,社区对应的社会经济系统、治理子系统,以及外部社会经济治理系统等方面存在的特殊性及不足,分析产生协同问题的原因;最后,提出了加强顶层制度设计、健全组织保障、优化工作机制、创新社区发展模式和加强科研支撑等对策建议。 展开更多
关键词 亚洲象肇事 农户损失 社会生态系统框架 中国
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基于结构方程模型的农户保护意愿影响因素分析:以东北虎豹国家公园珲春片区为例 被引量:4
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作者 杜宇晨 刘蓓萌 +2 位作者 陈俊峰 王浩 谢屹 《生物多样性》 CAS CSCD 北大核心 2024年第1期94-104,共11页
农户保护意愿直接影响到其后续的保护行为,进而影响到保护工作成效。基于2022年7–8月对东北虎豹国家公园珲春片区周边社区农户的一对一访谈收集到的534份有效问卷,运用结构方程模型,讨论了农户保护意愿的影响因素。研究结果表明:(1)农... 农户保护意愿直接影响到其后续的保护行为,进而影响到保护工作成效。基于2022年7–8月对东北虎豹国家公园珲春片区周边社区农户的一对一访谈收集到的534份有效问卷,运用结构方程模型,讨论了农户保护意愿的影响因素。研究结果表明:(1)农户保护态度显著正向影响其保护意愿,农户的价值评价、经验评价以及产生结果的评价越高,保护意愿越高。(2)农户规范显著正向影响其保护意愿,是3个影响因素中最重要的影响因素,其中价值评价与产生结果评价等两个因素对农户参与保护的意愿影响程度较高,而经验性评价的影响程度相对较低。(3)知觉行为控制显著正向影响其保护意愿。农户对其自身时间投入、经济投入、专业技能投入方面的感知难度越低,则参与保护的意愿越强。(4)年龄对其保护意愿具有显著的正向影响。建议通过强化政策引导职能,鼓励开展长效培训活动,拓展农户保护参与渠道等方法来提升农户参与保护的意愿。 展开更多
关键词 东北虎豹国家公园 保护意愿 计划行为理论 结构方程模型
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Pressureless crystallization of glass toward scintillating composite with high crystallinity for radiation detection 被引量:2
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作者 Junzhou Tang Shichao Lv +9 位作者 Ziyu Lin Guanxin Du Manyun Tang Xu Feng Junpeng Guo Xiang Li junfeng chen Lei Wei Jianrong Qiu Shifeng Zhou 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第34期173-180,共8页
The construction of scintillating ceramics is of great technological importance for various fundamental applications, including medical diagnostic, security inspection, resource exploration and particle physics. The c... The construction of scintillating ceramics is of great technological importance for various fundamental applications, including medical diagnostic, security inspection, resource exploration and particle physics. The chief challenge is the facile and scalable synthesis of scintillating ceramics with the desirable combination of pore-free, reliable mechanical properties and excellent scintillating performance. Here we present a pressureless glass crystallization strategy for the construction of scintillating composite with high crystallinity. The fabricated scintillating composites are featured by small optical turbidity, excellent mechanical properties, and efficient scintillating luminescence with the scintillating light yield of 15,000 pH/MeV and about 2.46 times higher than that of the commercial BGO single crystal. Moreover, the scintillating composite derived radiation detector device is successfully elaborated. The practical application for monitoring gamma ray is demonstrated and the precision of the device is less than that of the tolerable deviation of 30%. Our results suggest an innovative approach for expanding the category of scintillating material candidates, pointing to practical application in the field of radiation detection. 展开更多
关键词 GLASS Glass crystallization Optical materials COMPOSITE LUMINESCENCE
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A new strategy for fabrication of unique heterostructured titanium laminates and visually tracking their synchronous evolution of strain partitions versus microstructure 被引量:2
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作者 Hao Ding Xiping Cui +7 位作者 Zhiqi Wang Tao Zhao Yuchen Wang Yuanyuan Zhang Hongtao chen Lujun Huang Lin Geng junfeng chen 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第12期70-81,共12页
Heterostructured(HS)material with extraordinary mechanical properties has been regarded as one of the most promising structural materials.Here,we reported a new strategy for preparing heterostructured pure titanium la... Heterostructured(HS)material with extraordinary mechanical properties has been regarded as one of the most promising structural materials.Here,we reported a new strategy for preparing heterostructured pure titanium laminates that possess a good combination of strength and ductility by combining gradient structure(GS)and heterogeneous lamella structure(HLS).The deformation characteristic versus microstructure evolution of GS/HLS titanium laminates,namely the strain partitions between different-sized grains(480–25μm)was visualized using a scanning electron microscope(SEM)equipped with electron backscattered diffraction(EBSD)mode combined with the digital image correlation(SEM-DIC)with an ultrahigh spatial resolution for the first time.As a result,the hetero-deformation of unique GS/HLS structure by the characteristic of strain partitions could be accurately captured.While the hetero-deformation could result in the hetero-deformation induced(HDI)stress strengthening and HDI hardening,which were regarded as the key reason that the resulting GS/HLS Ti laminates showed a superior combination of strength and ductility.This could promote a more in-depth understanding of the strengtheningtoughening mechanism of heterostructured material. 展开更多
关键词 Gradient structure Heterogeneous lamella structure Digital image correlation Strain partition
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Signature of Superconductivity in Pressurized Trilayer-Nickelate Pr_(4)Ni_(3)O_(10−δ) 被引量:3
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作者 Xing Huang Hengyuan Zhang +7 位作者 Jingyuan Li Mengwu Huo junfeng chen Zhengyang Qiu Peiyue Ma Chaoxin Huang Hualei Sun Meng Wang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第12期166-172,共7页
The discovery of high-temperature superconductivity in La_(3)Ni_(2)O_(7) and La_(4)Ni_(3)O_(10) under pressure has garnered extensive attention.Herein,we report systematic investigations on the structure,magnetism,and... The discovery of high-temperature superconductivity in La_(3)Ni_(2)O_(7) and La_(4)Ni_(3)O_(10) under pressure has garnered extensive attention.Herein,we report systematic investigations on the structure,magnetism,and electrical resistance evolutions of Pr_(4)Ni_(3)O_(10−δ)polycrystalline samples under various pressures.Pr_(4)Ni_(3)O_(10−δ)exhibits density wave transitions on Ni and Pr sublattices at approximately 157.6 and 4.3 K,respectively.The density wave can be progressively suppressed by pressure.A structural transformation from the monoclinic P21/a space group to the tetragonal I4/mmm occurs around 20GPa.An apparent drop in resistance with an evident magnetic field dependence is observed at pressures above 20GPa,indicating the emergence of superconductivity.The discovery of superconductivity in Pr_(4)Ni_(3)O_(10−δ)broadens the family of nickelate superconductors.Pr_(4)Ni_(3)O_(10−δ)provides a new platform for investigation of the mechanisms of superconductivity in the Ruddlesden-Popper phases of nickelates. 展开更多
关键词 SUPERCONDUCTIVITY APPARENT
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Microbial community coexisting with harmful alga Karenia mikimotoi and microbial control of algal bloom in laboratory 被引量:1
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作者 Li SUN Peike GAO +7 位作者 Yu LI Chao WANG Ning DING junfeng chen Yuhao SONG Chunchen LIU Lun SONG Renjun WANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第3期1027-1038,共12页
Algicidal bacteria have been frequently isolated from algal blooming areas.However,knowledge regarding the microbial communities coexisting with microalgae and their potential application in preventing harmful algal b... Algicidal bacteria have been frequently isolated from algal blooming areas.However,knowledge regarding the microbial communities coexisting with microalgae and their potential application in preventing harmful algal blooms(HABs)is limited.In this study,we investigated the composition of the microbial community coexisting with harmful alga Karenia mikimotoi and its responses to algal control via nutrient stimulation or by adding algicidal strain in microcosms.The microorganisms inhabiting the K.mikimotoi culture consisted of 24 identifi ed phyla,including dominant Proteobacteria(relative abundance 76.24%±7.28%)and Bacteroidetes(22.67%±8.32%).Rhodobacteraceae,Phaeodactylibacter,and Maritimibacter predominated during the algal cultivation.Both the added nutrient and fermentation broth of algicidal strain Pseudoalteromonas QF1 caused a massive death of K.mikimotoi and substantial changes in the coexisting microbial community,in which Rhodobacteraceae and Phaeodactylibacter signifi cantly decreased,while Halomonas and Alteromonas increased.Core operational taxonomic units(OTUs)analysis indicated that 13 OTUs belonging to Rhodobacteraceae,Maritimibacter,Marivita,Nisaea,Phaeodactylibacter,Citreicella,Halomonas,Alteromonas,Marinobacter,Muricauda,and Pseudoalteromonas dominated the changes of the microbial communities observed in the K.mikimotoi culture with or without treatments.Collectively,this study indicated that microbial community inhabiting K.mikimotoi culture includes potential algicidal bacteria,and improves our knowledge about microbial community succession during biocontrol of K.mikimotoi via nutrient stimulation or by adding isolated algicidal strains. 展开更多
关键词 Karenia mikimotoi microbial community nutrient stimulation algicidal bacteria PSEUDOALTEROMONAS
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Using NSGA-Ⅲ for optimising biomedical ontology alignment 被引量:1
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作者 Xingsi Xue Jiawei Lu junfeng chen 《CAAI Transactions on Intelligence Technology》 2019年第3期135-141,共7页
To support semantic inter-operability between the biomedical information systems, it is necessary to determine the correspondences between the heterogeneous biomedical concepts, which is commonly known as biomedical o... To support semantic inter-operability between the biomedical information systems, it is necessary to determine the correspondences between the heterogeneous biomedical concepts, which is commonly known as biomedical ontology matching. Biomedical concepts are usually complex and ambiguous, which makes matching biomedical ontologies a challenge. Since none of the similarity measures can distinguish the heterogeneous biomedical concepts in any context independently, usually several similarity measures are applied together to determine the biomedical concepts mappings. However, the ignorance of the effects brought about by different biomedical concept mapping’s preference on the similarity measures significantly reduces the alignment’s quality. In this study, a non-dominated sorting genetic algorithm (NSGA)-III-based biomedical ontology matching technique is proposed to effectively match the biomedical ontologies, which first utilises an ontology partitioning technique to transform the large-scale biomedical ontology matching problem into several ontology segment-matching problems, and then uses NSGA-III to determine the optimal alignment without tuning the aggregating weights. The experiment is conducted on the anatomy track and large biomedic ontologies track which are provided by the Ontology Alignment Evaluation Initiative (OAEI), and the comparisons with OAEI’s participants show the effectiveness of the authors’ approach. 展开更多
关键词 ONTOLOGY ontologies TRANSFORM TOGETHER ONTOLOGY COMPLEX CONTEXT effects
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“醉驾”行为出罪与入罪路径探析——以甘肃省司法裁判为分析样本 被引量:1
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作者 党崇武 杨芳 +1 位作者 陈峻锋 杨世昌 《西北成人教育学院学报》 2023年第3期104-112,共9页
对2011—2022年中国裁判文书网上公布的甘肃省境内所有醉酒型危险驾驶罪判决书,进行定量分析和对比分析,可以发现醉酒型危险驾驶罪不仅具有案件数量多占比居高不下等普遍问题外,还存在缓刑适用比例高但缓刑适用不当等特别问题。因此,醉... 对2011—2022年中国裁判文书网上公布的甘肃省境内所有醉酒型危险驾驶罪判决书,进行定量分析和对比分析,可以发现醉酒型危险驾驶罪不仅具有案件数量多占比居高不下等普遍问题外,还存在缓刑适用比例高但缓刑适用不当等特别问题。因此,醉驾案件野蛮发展至今,在已颁布的多个司法解释尚不足以有效控制醉驾案件爆发式增长的情况下,有必要通过重构抽象危险犯理论,引入准抽象危险犯(适格犯)概念,为“醉驾”行为入罪“节流”;完善酌定不起诉制度,为“醉驾”行为出罪“开源”;以血液酒精含量为基本依据,辅以其他多种量刑情节,明确缓刑适用标准的同时构建本省的量刑阶梯,实现量刑均衡、缓刑有据、罪责刑相符,进而有效缓解醉酒型危险驾驶罪为司法机关、涉案人员和整个社会带来的矛盾与冲突。 展开更多
关键词 醉酒型危险驾驶罪 准抽象危险犯 酌定不起诉 缓刑
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Simulated and experimental studies on the array dielectric barrier discharge of water electrodes
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作者 Lele WANG Xiutao HUANG +3 位作者 junfeng chen Shengming WANG Zhaoyang HU Minghai LIU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第3期75-82,共8页
A kind of dielectric barrier discharge(DBD) device composed of water electrodes with 3×3forms can produce large-area low-temperature plasmas at atmospheric pressure.To reflect the discharge characteristics of D... A kind of dielectric barrier discharge(DBD) device composed of water electrodes with 3×3forms can produce large-area low-temperature plasmas at atmospheric pressure.To reflect the discharge characteristics of DBD better,a dynamic simulation model,which is based on the voltage controlled current source(CCS),is established,then the established model in Matlab/Simulink is used to simulate the DBD in air.The voltage-current waves and Lissajous at a voltage of 10 kV,11 kV and 12 kV peak value with a frequency of 15 kHz are studied.The change of the discharge power of DBD with a different amplitude and frequency of applied voltage is also analyzed.The result shows the voltage-current waves,Lissajous and discharge power of DBD under different conditions from the simulation agree well with those of the experiment.In addition,we propose a method to calculate the dielectric barrier capacitance Cd and the gap capacitance Cg,which is valid through analyzing the variation of capacitance at different voltage amplitudes. 展开更多
关键词 dielectric barrier discharge MATLAB/SIMULINK lissajous dielectric barrier capaci-tance gap capacitance
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The ABC transporter SmABCG1 mediates tanshinones export from the peridermic cells of Salvia miltiorrhiza root 被引量:2
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作者 Yajing Li junfeng chen +19 位作者 Jingyu Zhi Doudou Huang Yuchen Zhang Lei Zhang Xinyi Duan Pan Zhang Shi Qiu Jiaran Geng Jingxian Feng Ke Zhang Xu Yang Shouhong Gao Wenwen Xia Zheng Zhou Yuqi Qiao Bo Li Qing Li Tingzhao Li Wansheng chen Ying Xiao 《Journal of Integrative Plant Biology》 2025年第1期135-149,共15页
Plants have mechanisms to transport secondary metabolites from where they are biosynthesized to the sites where they function,or to sites such as the vacuole for detoxification.However,current research has mainly focu... Plants have mechanisms to transport secondary metabolites from where they are biosynthesized to the sites where they function,or to sites such as the vacuole for detoxification.However,current research has mainly focused on metabolite biosynthesis and regulation,and little is known about their transport.Tanshinone,a class diterpenoid with medicinal properties,is biosynthesized in the periderm of Salvia miltiorrhiza roots.Here,we discovered that tanshinone can be transported out of peridermal cells and secreted into the soil environment and that the ABC transporter SmABCG1 is involved in the efflux of tanshinoneⅡA and tanshinoneⅠ.The SmABCG1 gene is adjacent to the diterpene biosynthesis gene cluster in the S.miltiorrhiza genome.The temporal–spatial expression pattern of SmABCG1 is consistent with tanshinone accumulation profiles.SmABCG1 is located on the plasma membrane and preferentially accumulates in the peridermal cells of S.miltiorrhiza roots.Heterologous expression in Xenopus laevis oocytes demonstrated that SmABCG1 can export tanshinoneⅡA and tanshinoneⅠ.CRISPR/Cas9-mediated mutagenesis of SmABCG1 in S.miltiorrhiza hairy roots resulted in a significant decrease in tanshinone contents in both hairy roots and the culture medium,whereas overexpression of this gene resulted in increased tanshinone contents.CYP76AH3 transcript levels increased in hairy roots overexpressing SmABCG1 and decreased in knockout lines,suggesting that SmABCG1 may affect the expression of CYP76AH3,indirectly regulating tanshinone biosynthesis.Finally,tanshinoneⅡA showed cytotoxicity to Arabidopsis roots.These findings offer new perspectives on plant diterpenoid transport and provide a new genetic tool for metabolic engineering and synthetic biology research. 展开更多
关键词 ATP-binding cassette transporter biosynthesis gene cluster CYTOTOXICITY EXPORT peridermic cells TANSHINONE
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Functional evolution and diversification of CYP82D subfamily members have shaped flavonoid diversification in the genus Scutellaria 被引量:1
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作者 Shi Qiu Jing Wang +13 位作者 Tianlin Pei Ranran Gao Chunlei Xiang junfeng chen chen Zhang Ying Xiao Qing Li Ziding Wu Min He Rong Wang Qing Zhao Zhichao Xu Jiadong Hu Wansheng chen 《Plant Communications》 2025年第1期95-113,共19页
Flavonoids,the largest class of polyphenols,exhibit substantial structural and functional diversity,yet their evolutionary diversification and specialized functions remain largely unexplored.The genus Scutellaria is n... Flavonoids,the largest class of polyphenols,exhibit substantial structural and functional diversity,yet their evolutionary diversification and specialized functions remain largely unexplored.The genus Scutellaria is notable for its rich flavonoid diversity,particularly of 6/8-hydroxylated variants biosynthesized by the cytochrome P450 subfamily CYP82D.Our study analyzes metabolic differences between Scutellaria baicalensis and Scutellaria barbata,and the results suggest that CYP82Ds have acquired a broad range of catalytic functions over their evolution.By integrating analyses of metabolic networks and gene evolution across 22 Scutellaria species,we rapidly identified 261 flavonoids and delineated five clades of CYP82Ds associated with various catalytic functions.This approach revealed a unique catalytic mode for 6/8-hydroxylation of flavanone substrates and the first instance of 7-O-demethylation of flavonoid substrates catalyzed by a cytochrome P450.Ancestral sequence reconstruction and functional validation demonstrated that gradual neofunctionalization of CYP82Ds has driven the chemical diversity of flavonoids in the genus Scutellaria throughout its evolutionary history.These findings enhance our understanding of flavonoid diversity,reveal the intricate roles of CYP82Ds in Scutellaria species,and highlight the extensive catalytic versatility of cytochrome P450 members within plant taxa. 展开更多
关键词 SCUTELLARIA CYP82D subfamily FLAVONOIDS DEMETHYLATION evolutionary diversity
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Supervised projection with adaptive label assignment for enhanced visualization and chemical process monitoring
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作者 Zhi Li junfeng chen +1 位作者 Kaige Xue Xin Peng 《Frontiers of Chemical Science and Engineering》 2025年第7期15-32,共18页
Data-driven process monitoring methods are widely used in industrial tasks,with visual monitoring enabling operators to intuitively understand operational status,which is vital for maximizing industrial safety and pro... Data-driven process monitoring methods are widely used in industrial tasks,with visual monitoring enabling operators to intuitively understand operational status,which is vital for maximizing industrial safety and production efficiency.However,high-dimensional industrial data often exhibit complex structures,making the traditional 2D visualization methods ineffective at distinguishing different fault types.Thus,a visual process monitoring method that combines supervised uniform manifold approximation and projection with a label assignment strategy is proposed herein.First,the proposed supervised projection method enhances the visualization step by incorporating label information to guide the nonlinear dimensionality reduction process,improving the degrees of class separation and intraclass compactness.Then,to address the lack of label information for online samples,a label assignment strategy is designed.This strategy integrates kernel Fisher discriminant analysis and Bayesian inference,assigning different label types to online samples based on their confidence levels.Finally,upon integrating the label assignment strategy with the proposed supervised projection method,the assigned labels enhance the separability of online projections and enable the visualization of unknown data to some extent.The proposed method is validated on the Tennessee Eastman process and a real continuous catalytic reforming process,demonstrating superior visual fault monitoring and diagnosis performance to that of the state-of-the-art methods,especially in real industrial applications. 展开更多
关键词 visual process monitoring supervised uniform manifold approximation and projection kernel Fisher discriminant analysis Bayesian inference
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TRICHOMEAND ARTEMISININ REGULATOR 1 Is Required for Trichome Development and Artemisinin Biosynthesis in Artemisia annua 被引量:45
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作者 Hexin Tan Ling Xiao +7 位作者 Shouhong Gao Qing Li junfeng chen Ying Xiao Qian Ji Ruibing chen Wansheng chen Lei Zhang 《Molecular Plant》 SCIE CAS CSCD 2015年第9期1396-1411,共16页
Trichomes, small protrusions on the surface of many plant species, can produce and store various secondary metabolic products. Artemisinin, the most famous and potent medicine for malaria, is synthesized, stored, and ... Trichomes, small protrusions on the surface of many plant species, can produce and store various secondary metabolic products. Artemisinin, the most famous and potent medicine for malaria, is synthesized, stored, and secreted by Artemisia annua trichomes. However, the molecular basis regulating the biosynthesis of artemisinin and the development of trichomes in A. annua remains poorly understood. Here, we report that an AP2 transcription factor, TRICHOME AND ARTEMISININ REGULATOR 1 (TAR1), plays crucial roles in regulating the development of trichomes and the biosynthesis of artemisinin in A. annua. TAR1, which encodes a protein specially located in the nucleus, is mainly expressed in young leaves, flower buds, and some trichomes. In TAR1-RNAi lines, the morphology of trichomes and the composition of cuticular wax were altered, and the artemisinin content was dramatically reduced, which could be significantly increased by TAR1 oeverexpression. Expression levels of several key genes that are involved in artemisinin biosynthesis were altered when TAR1 was silenced or overexpressed. By the electrophoretic mobility shift, yeast one-hybrid and transient transformation β-glucuronidase assays, we showed that ADS and CYP71AV1, two key genes in the biosynthesis pathway of artemisinin, are likely the direct targets of TAR1. Taken together, our results indicate that TAR1 is a key component of the molecular network regulating trichome development and artemisinin biosynthesis in A. annua. 展开更多
关键词 Artemisia annua ARTEMISININ TRICHOME AP2 transcription factor WAX
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The ERF transcription factor LTF1 activates DIR1 to control stereoselective synthesis of antiviral lignans and stress defense in Isatis indigotica roots 被引量:3
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作者 Ruibing chen Jian Yu +9 位作者 Luyao Yu Liang Xiao Ying Xiao junfeng chen Shouhong Gao Xianghui chen Qing Li Henan Zhang Wansheng chen Lei Zhang 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2024年第1期405-420,共16页
Lignans are a powerful weapon for plants to resist stresses and have diverse bioactive functions to protect human health.Elucidating the mechanisms of stereoselective biosynthesis and response to stresses of lignans i... Lignans are a powerful weapon for plants to resist stresses and have diverse bioactive functions to protect human health.Elucidating the mechanisms of stereoselective biosynthesis and response to stresses of lignans is important for the guidance of plant improvement.Here,we identified the complete pathway to stereoselectively synthesize antiviral(-)-lariciresinol glucosides in Isatis indigotica roots,which consists of three-step sequential stereoselective enzymes DIR1/2,PLR,and UGT71B2.DIR1 was further identified as the key gene in respoJanuary 2024nse to stresses and was able to trigger stress defenses by mediating the elevation in lignan content.Mechanistically,the phytohormone-responsive ERF transcription factor LTF1 colocalized with DIR1 in the cell periphery of the vascular regions in mature roots and helped resist biotic and abiotic stresses by directly regulating the expression of DIR1.These systematic results suggest that DIR1 as the first common step of the lignan pathway cooperates with PLR and UGT71B2 to stereoselectively synthesize(-)-lariciresinol derived antiviral lignans in I.indigotica roots and is also a part of the LTF1-mediated regulatory network to resist stresses.In conclusion,the LTF1-DIR1 module is an ideal engineering target to improve plant Defenses while increasing the content of valuable lignans in plants. 展开更多
关键词 Lignans Stereoselective synthesis Stress resistance Dirigent protein ERF
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Structural transition,electric transport,and electronic structures in the compressed trilayer nickelate La_(4)Ni_(3)O_(10) 被引量:2
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作者 Jingyuan Li Cui-Qun chen +13 位作者 Chaoxin Huang Yifeng Han Mengwu Huo Xing Huang Peiyue Ma Zhengyang Qiu junfeng chen Xunwu Hu Lan chen Tao Xie Bing Shen Hualei Sun Dao-Xin Yao Meng Wang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2024年第11期9-15,共7页
Atomic structure and electronic band structure are fundamental properties for understanding the mechanism of superconductivity. Motivated by the discovery of pressure-induced high-temperature superconductivity at 80 K... Atomic structure and electronic band structure are fundamental properties for understanding the mechanism of superconductivity. Motivated by the discovery of pressure-induced high-temperature superconductivity at 80 K in the bilayer Ruddlesden-Popper nickelate La_(3)Ni_(2)O_(7), the atomic structure and electronic band structure of the trilayer nickelate La_(4)Ni_(3)O_(10) under pressure up to 44.3 GPa are investigated. A structural transition from the monoclinic P2_(1)/a space group to the tetragonal I4/mmm around 12.6-13.4 GPa is identified, accompanied by a drop of resistance below 7 K. Density functional theory calculations suggest that the bonding state of Ni 3d_(z^(2)) orbital rises and crosses the Fermi level at high pressures, which may give rise to possible superconductivity observed in resistance under pressure in La_(4)Ni_(3)O_(10). The trilayer nickelate La_(4)Ni_(3)O_(10) shows some similarities with the bilayer La_(3)Ni_(2)O_(7) and has unique properties, providing a new platform to investigate the underlying mechanism of superconductivity in nickelates. 展开更多
关键词 La_(4)Ni_(3)O_(10) high pressure synchrotron X-ray diffraction structural transition DFT calculations
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