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Preparation Process and Thin Layer Chromatography Identification of Wufang Babu Poultice
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作者 junjun liu Luyao XIE +2 位作者 Chuhui ZHOU Zhengteng YANG Xiongbin GUI 《Medicinal Plant》 CAS 2023年第4期58-61,共4页
[Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the prepar... [Objectives] To establish the process flow of preparation of Wufang Babu Poultice and the identification method of thin layer chromatography (TLC). [Methods] For the forming process of Wufang Babu Poultice, the preparation method of mixed pharmaceutical powder with suitable pharmaceutical excipients was adopted. Qualitative identification of medicinal materials in Wufang Babu Poultice (Strychni Semen, Rhei Radix Et Rhizoma, Dipsaci Radix, and Angelicae Sinensis Radix) was carried out by TLC. [Results] Mixed pharmaceutical powder mixed with glycerol, gelatin and other pharmaceutical excipients can be prepared for forming. The test solution chromatography of each medicinal material (Strychni Semen, Rhei Radix et Rhizoma, Dipsaci Radix, Angelicae Sinensis Radix) showed pigment spots of the same color at the same position as its corresponding control medicinal materials and reference chromatography, and the display was clear. [Conclusions] The preparation process is simple and feasible, and can be used as the forming process of Wufang Babu Poultice. The TLC determination method is simple to operate, has good specificity, and has no effect on negative results, and can be used for identification of Wufang Babu Poultice. 展开更多
关键词 Wufang Babu Poultice Preparation process Thin layer chromatography(TLC)
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Mechanical behavior of coal under different mining rates:A case study from laboratory experiments to field testing 被引量:40
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作者 Mingzhong Gao Jing Xie +5 位作者 Yanan Gao Wenyong Wang Cong Li Bengao Yang junjun liu Heping Xie 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第5期825-841,共17页
During the development of hot dry rock,the research on thermal fatigue damage caused by thermal shock of cold and heat cycles is the basis that ensures the long-term utilization of geothermal resources,but there are n... During the development of hot dry rock,the research on thermal fatigue damage caused by thermal shock of cold and heat cycles is the basis that ensures the long-term utilization of geothermal resources,but there are not enough relevant studies at present.Based on this,the thermal damage tests of granite at different temperatures(250,350,450°C)and quenching cycles(1,5,10,15 cycles)were carried out.Preliminary reveals the damage mechanism and heat transfer law of the quenching cycle effect on hot dry rock.The results show that with the increase of temperature and cycles,the uneven thermal expansion of minerals and the thermal shock caused by quenching promote the crack development of granite,resulting in the decrease of P-wave velocity,thermal conductivity and uniaxial compressive strength of granite.Meanwhile,the COMSOL was used to simulate the heat transfer of hot dry rock under different heat treatment conditions.It concluded that the increase in the number of quenching cycles reduced the heat transfer capacity of the granite,especially more than 10 quenching cycles,which also reflects that the thermal fatigue damage leads to a longer time for the temperature recovery of the hot dry rock mass.In addition,the three-dimensional nonlinear fitting relationship among thermal conductivity,temperature and cycle number was established for the first time,which can better reveal the change rule of thermal conductivity after quenching thermal fatigue effect of hot dry rock.The research results provide theoretical support for hot dry rock reservoir reconstruction and production efficiency evaluation. 展开更多
关键词 Mining rate Loading rate Fracture evolution Mining pressure Uniaxial compressive strength DIC
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基于磁共振成像乳腺癌远处转移预测模型的研究 被引量:6
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作者 汤加 马文娟 +2 位作者 刘君君 邵真真 刘佩芳 《中国肿瘤临床》 CAS CSCD 北大核心 2019年第7期337-341,共5页
目的:建立基于平扫磁共振成像(magnetic resonance imaging,MRI)和动态对比增强(dynamic contrast enhanced,DCE)-MRI影像特征参数的乳腺癌远处转移预测模型。方法:回顾性分析2011年1月至2016年12月3 032例于天津医科大学肿瘤医院行乳腺... 目的:建立基于平扫磁共振成像(magnetic resonance imaging,MRI)和动态对比增强(dynamic contrast enhanced,DCE)-MRI影像特征参数的乳腺癌远处转移预测模型。方法:回顾性分析2011年1月至2016年12月3 032例于天津医科大学肿瘤医院行乳腺MRI检查并经病理证实为乳腺浸润性癌患者的临床资料,根据纳入标准筛选出转移组93例和非转移组186例。分析转移组远处转移部位与分子分型的关系,同时对两组MRI影像特征进行单因素分析及多因素Logistics回归分析,获得独立预测因子并建立预测模型。结果:转移组中Luminal型、HER-2过表达型、三阴性乳腺癌最常见远处转移部位分别为骨、肝脏、肺脏。单因素分析结果显示,两组间的病变类型、是否多发、T1WI和T2WI信号均匀度及病灶最大径进行比较差异具有统计学意义(P<0.05)。多因素Logistics回归分析结果显示,病变类型、是否多发、T2WI信号均匀度及病灶最大径为独立预测因子。根据独立预测因子建立的预测模型准确率、敏感度、特异度和受试者工作特征曲线(receiver operating characteristic,ROC)下面积(area under receiver operating characteristic curve,AUC)分别为82.8%、85.7%、75.0%和0.801。结论:基于MRI影像特征的模型对预测乳腺癌远处转移具有潜在价值。 展开更多
关键词 乳腺癌 肿瘤转移 磁共振成像 预测 分子分型
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Work-family conflict and job burn-out among Chinese doctors:the mediating role of coping styles 被引量:7
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作者 Ling Chen junjun liu +10 位作者 Hailong Yang Hui Ma Hui Wang Yun Huang Hao Cheng Dianzhen Tang Miao liu Houyuan Luo Haitao Qu Diwen Shen Ning Zhang 《General Psychiatry》 CSCD 2018年第4期24-30,共7页
Background Burn-out among doctors threatens their own health, and that of their patients. To identify risk factors of the doctor burn-out is vital to improving their health and increasing the quality of healthcare ser... Background Burn-out among doctors threatens their own health, and that of their patients. To identify risk factors of the doctor burn-out is vital to improving their health and increasing the quality of healthcare services.This study aims to explore the relationship between workfamily conflict(WFC) and burn-out among Chinese doctors and the mediating role of coping styles in this relationship.Methods A cross-sectional survey was conducted in China, with a questionnaire packet which consisted of the Chinese Maslach Burnout Inventory(CMBI), WFC Scale and the Simplified Coping Style Questionnaire(SCSQ). A total of 2530 doctors participated in the survey. Correlation analysis was performed to explore the relationship between CMBI, WFC and SCSQ scores. A linear regression model was set to determine the mediating role of coping styles on the relationship between WFC and burn-out.Results Doctors who had higher scores on work interfering with family conflict, reported more emotional exhaustion(r=0.514, P<0.001) and had a sense of accomplishment(r=-0.149, P<0.001). Simultaneously,family interfering with work(FIW) was positively associated with all dimensions of burn-out(r=0.213,0.504,0.088,respectively, P<0.001). Coping styles had partial, complete and even mediating effects on the relationship between WFC and burn-out among Chinese doctors.Conclusions WFC was correlated with burn-out, and coping style was a mediator in this relationship among Chinese doctors. Coping style was a positive resource against burn?out. 展开更多
关键词 WFC WIF
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多模态超声检查对腹壁下动脉穿支皮瓣自体移植乳房再造术前血管评估研究 被引量:2
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作者 刘雪静 路红 +4 位作者 徐熠琳 李小康 季宇 刘君君 朱鹰 《中国肿瘤临床》 CAS CSCD 北大核心 2020年第24期1261-1264,共4页
目的:探讨多模态超声对腹壁下动脉穿支(deep inferior epigastric perforator,DIEP)皮瓣血管检查有效性,并分析穿支血管的影响因素。方法:纳入2013年2月至2018年10月43例于天津医科大学肿瘤医院使用DIEP皮瓣进行乳房再造术的女性乳腺癌... 目的:探讨多模态超声对腹壁下动脉穿支(deep inferior epigastric perforator,DIEP)皮瓣血管检查有效性,并分析穿支血管的影响因素。方法:纳入2013年2月至2018年10月43例于天津医科大学肿瘤医院使用DIEP皮瓣进行乳房再造术的女性乳腺癌患者,对穿支血管行术前常规及彩色多普勒超声检查,并在超声造影增强状态下行三维重建,直观显示穿支血管的走行分布情况,同时体表标注投影位置。结果:43例患者腹壁下动脉穿支主要分布在脐周5 cm范围内,每侧2~5支,其中28例呈不对称分布。DIEP穿支血管管径与患者腹壁脂肪层厚度呈正相关(r=0.436,P<0.05);血管收缩期峰值血流速度与穿支血管管径呈正相关(r=0.448,P<0.05)。43例患者行超声造影检查后彩色血流信号均能显著增强,其中39例经三维重建后能清晰显示穿支血管与腹壁下动脉主干的关系,4例穿支血管显示欠连续。结论:多模态超声检查在乳腺癌患者DIEP乳房再造术前评估穿支血管具有重要的应用价值,腹壁脂肪层厚度对优势血管的选择有一定影响。 展开更多
关键词 腹壁下动脉 穿支皮瓣 彩色多普勒 超声造影 三维重建
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An Efficient Webpage Classification Algorithm Based on LSH
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作者 junjun liu Haichun Sun Zhijun Ding 《国际计算机前沿大会会议论文集》 2015年第1期73-75,共3页
With the explosive growth of Internet information, it is more and more important to fetch real-time and related information. And it puts forward higher requirement on the speed of webpage classification which is one o... With the explosive growth of Internet information, it is more and more important to fetch real-time and related information. And it puts forward higher requirement on the speed of webpage classification which is one of common methods to retrieve and manage information. To get a more efficient classifier, this paper proposes a webpage classification method based on locality sensitive hash function. In which, three innovative modules including building feature dictionary, mapping feature vectors to fingerprints using Localitysensitive hashing, and extending webpage features are contained. The compare results show that the proposed algorithm has better performance in lower time than the naive bayes one. 展开更多
关键词 EXPLOSIVE growth Webpage classification Locality-sensitive HASHING FINGERPRINT EXTENDING webpage features
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Talaroclauxins A and B:Duclauxin-ergosterol and duclauxin-polyketide hybrid metabolites with complicated skeletons from Talaromyces stipitatus
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作者 Qin Li Mi Zhang +11 位作者 Xiaotian Zhang Lanqin Li Meijia Zheng Jinbing Kang Fei liu Qun Zhou Xiaonian Li Weiguang Sun junjun liu Chunmei Chen Hucheng Zhu Yonghui Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第1期300-304,共5页
Talaroclauxins A and B(1 and 2),two novel duclauxin hybrids,were obtained from Talaromyces stipitatus,along with three new(3-5)and one known analogue(6).Their structures were determined by NMR spectroscopy,HRESIMS,sin... Talaroclauxins A and B(1 and 2),two novel duclauxin hybrids,were obtained from Talaromyces stipitatus,along with three new(3-5)and one known analogue(6).Their structures were determined by NMR spectroscopy,HRESIMS,single-crystal X-ray diffraction,and quantum chemical calculations.Compound 1 is the first example of duclauxin-ergosterol hybrid featuring an unprecedented dodecacyclic ring system formed via a[4+2]cycloaddition,while compound 2,bearing an unusual 6/6/6/5/6/6/6/6 ring system,is a new member of the rare duclauxin-polyketide hybrid class of natural products.Plausible biosynthetic pathways for 1-6 are proposed.Compound 5 displayed moderate neuroprotective effects in glutamate sodium-induced SH-SY5Y cells. 展开更多
关键词 Talaromyces stipitatus(Trichocomaceae) Duclauxin hybrids Single-crystal X-ray diffraction Biosynthetic pathways Neuroprotective effects
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AbnI:Anα-ketoglutarate-dependent dioxygenase involved in brassicicene C-H functionalization and ring system rearrangement
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作者 Wenling Yuan Fengli Li +8 位作者 Zhe Chen Qiaoxin Xu Zhenhua Guan Nanyu Yao Zhengxi Hu junjun liu Yuan Zhou Ying Ye Yonghui Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期213-217,共5页
We reported the characterization of a novel brassicicene diterpene biosynthetic gene cluster,which contains a uniqueα-ketoglutarate-dependent dioxygenase(αKGD)enzyme,AbnI.Our findings revealed that AbnI demonstrates... We reported the characterization of a novel brassicicene diterpene biosynthetic gene cluster,which contains a uniqueα-ketoglutarate-dependent dioxygenase(αKGD)enzyme,AbnI.Our findings revealed that AbnI demonstrates remarkable substrate promiscuity and is capable of activating multiple sites on both 5-8-5 and 5-9-5 brassicicene skeletons,resulting in skeleton modifications and an unexpected ring system rearrangement.These results suggested the potential utility of AbnI as an enzymatic tool for terpene C-H functionalization.In addition,the catalytic mechanism of AbnI and its potential ecological implications were discussed. 展开更多
关键词 Fungal diterpenes α-Ketoglutarate-dependent dioxygenase C-H functionalization REARRANGEMENT Brassicicenes
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Highly efficient solid-state luminescence of carbonized polymer dots without matrix
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作者 Rui Li junjun liu +3 位作者 Chunlei Xia Tanglue Feng Zhicheng Zhu Bai Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第6期412-416,共5页
Development of high-performance solid state luminescent carbon-based nanomaterials remains challenging.Here,strong blue-green fluorescent carbonized polymer dots(CPDs)from o-aminobenzenethiol and thiosalicylic acid(o ... Development of high-performance solid state luminescent carbon-based nanomaterials remains challenging.Here,strong blue-green fluorescent carbonized polymer dots(CPDs)from o-aminobenzenethiol and thiosalicylic acid(o ABT-TSA-CPDs)with an absolute photoluminescence quantum yield(PLQY)of 76%in solid state without matrix were synthesized.Through adjusting the reaction temperature and time,the PL centers were proved to be carbon core state and surface state associated to carbonyl group which was the source of strong fluorescence emission in solid state.The mechanism of the unique phenomenon of enhanced emission from ethanol solution(PLQY=7%)to powder(PLQY=76%)was investigated by analyzing the chemical properties and structures of o ABT-TSA-CPDs at different temperatures and o ABT-TSACPDs/PVC composites,and was confirmed as fixation of PL centers. 展开更多
关键词 Carbonized polymer dots Solid-state fluorescence MATRIX-FREE High performance Enhanced photoluminescence quantum yield
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QM/MM study on the O_(2)activation reaction of 4-hydroxylphenyl pyruvate dioxygenase reveals a common mechanism forα-ketoglutarate dependent dioxygenase
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作者 Linhui Li Suitian Lai +6 位作者 Hongyan Lin Xinyun Zhao Xin Li Xi Chen junjun liu Guangfu Yang Changguo Zhan 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第5期461-465,共5页
The dioxygen activation catalyzed by 4-hydorxylphenyl pyruvate dioxygenase(HPPD)were reinvestigated by using hybrid quantum mechanics/molecular mechanics(QM/MM)approaches at the B3LYP/6-311++G(d,p):AMBER level.These s... The dioxygen activation catalyzed by 4-hydorxylphenyl pyruvate dioxygenase(HPPD)were reinvestigated by using hybrid quantum mechanics/molecular mechanics(QM/MM)approaches at the B3LYP/6-311++G(d,p):AMBER level.These studies showed that this reaction consisted of two steps including the dioxygen addition/decarboxylation and hetero O-O bond cleavage,where the first step was found to be rate-determining.The former step initially runs on a septet potential energy surface(PES),then switches to a quintet PES after crossing a septet/quintet minimum energy crossing point(MECP)5-7M2,whereas the rest step runs on the quintet PES.The reliability of our theoretical predictions is supported by the excellent agreement of the calculated free-energy barrier value of 16.9 kcal/mol with available experimental value of 16-17 kcal/mol.The present study challenges the widely accepted view which holds that the O2activation catalyzed byα-keto glutamate(α-KG)dioxygenase mainly runs on the quintet PES and provides new insight into the catalytic mechanism ofα-KG dioxygenase and/or other related Fe(Ⅱ)-dependent oxygenase. 展开更多
关键词 4-Hydroxylphenyl pyruvate dioxygenase O_(2)activation QM/MM Mechanism Minimum energy crossing point
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Dual Nanofillers-Reinforced Noncovalently Cross-Linked Polymeric Composites with Unprecedented Mechanical Strength
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作者 Ni An Youliang Zhu +6 位作者 Xiaohan Wang Yixuan Li junjun liu Xu Fang Zhongyuan Lu Bai Yang Junqi Sun 《CCS Chemistry》 CSCD 2023年第10期2312-2323,共12页
Noncovalentlycross-linkedpolymermaterials through healing,recycling,and reprocessing can reduce materials consumption and alleviate environmental pollution.However,it remains a huge challenge to fabricate super-strong... Noncovalentlycross-linkedpolymermaterials through healing,recycling,and reprocessing can reduce materials consumption and alleviate environmental pollution.However,it remains a huge challenge to fabricate super-strong noncovalently cross-linked polymer materials with mechanical strength comparable to high-performance engineering polymers.Herein,healable and reprocessable noncovalently cross-linked polymer compositeswith an unprecedented mechanical strength are fabricated by complexation of polyacrylic acid(PAA),polyvinylpyrrolidone(PVPON),and carbonized polymer dots(CPDs)(denoted as PAA-PVPON-CPDs).The incorporation of 15 wt%CPDs generates PAA-PVPON-CPDs compositeswith a tensile strength of∼158 MPa and Young’s modulus of∼8.2GPa.Servingas nanofillers,theCPDs can establish strong interactions with polymers in PAA-PVPON composites.The CPDs and the in situ-formed PAAPVPON nanoparticles work in concert to significantly strengthen the PAA-PVPON-CPDs composites to an unprecedented strength.The PAA-PVPON-CPDs composites exhibit excellent impact resistance and damage tolerance because of the high mechanical strength of the composites and the energy dissipation mechanism of the CPDs and PAA-PVPON nanoparticles.Moreover,the fractured PAA-PVPON-CPDs composites can be healed to restore their original mechanical strength. 展开更多
关键词 carbonized polymer dots noncovalently cross-linked polymers supramolecular polymers self-healing materials
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The linkage maps of Dendrobium species based on RAPD and SRAP markers 被引量:26
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作者 Dawei Xue Shangguo Feng +6 位作者 Hongyan Zhao Hua Jiang Bo Shen Nongnong Shi Jiangjie Lu junjun liu Huizhong Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2010年第3期197-204,共8页
Dendrobium plants are used commonly as tonic herbs and health food in many Asian countries, especially in China. Here we report the genetic map construction of two Dendrobium species with a double pseudo-testcross str... Dendrobium plants are used commonly as tonic herbs and health food in many Asian countries, especially in China. Here we report the genetic map construction of two Dendrobium species with a double pseudo-testcross strategy using random amplified polymorphic DNA (RAPD) and sequence-related amplified polymorphism (SRAP) markers. A F1 mapping population of 90 individuals was developed from a cross between D. officinale and D. hercoglossum. A total of 307 markers, including 209 RAPD and 98 SRAP, were identified and used for genetic linkage group (LG) analysis. The D. officinale linkage map consisted of 11 major linkage groups and 3 doublets, which covered 629.4 cM by a total of 62 markers with an average locus distance of 11.2 cM between two adjacent markers. The D. hercoglos- sum linkage map contained 112 markers mapped on 15 major and 4 minor linkage groups, spanning a total length of 1,304.6 cM with an average distance of I 1.6 cM between two adjacent markers. The maps constructed in this study covered 92.7% and 82.7% of the D. hercoglossum and D. officinale genomes respectively, providing an important basis for the mapping of horticultural and medicinal traits and for the application of marker-assisted selection in Dendrobium breeding program. 展开更多
关键词 DENDROBIUM genetic linkage map RAPD SRAP
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原发性逆撕型Stanford A型主动脉夹层的研究进展
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作者 张恒 刘军军 +1 位作者 肖顺 郭明金 《中华介入放射学电子杂志》 2022年第3期301-305,共5页
目的原发性逆撕型Stanford A型主动脉夹层(RTAD)的特征是原发裂口位于无名动脉以远,夹层的假腔逆行撕裂累及升主动脉。由于其解剖结构复杂,危险性高,RTAD仍是大动脉外科极具挑战性的难题。对于这种特殊类型夹层的治疗方式,目前尚无共识... 目的原发性逆撕型Stanford A型主动脉夹层(RTAD)的特征是原发裂口位于无名动脉以远,夹层的假腔逆行撕裂累及升主动脉。由于其解剖结构复杂,危险性高,RTAD仍是大动脉外科极具挑战性的难题。对于这种特殊类型夹层的治疗方式,目前尚无共识。文章分析了相关文献,主要针对RTAD的流行病学、解剖特征、发病机制及治疗方案等方面作一综述,以期为临床诊疗工作提供指导。 展开更多
关键词 原发性逆撕型Stanford A型主动脉夹层 升主动脉 治疗方式
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The structure of 4-hydroxylphenylpyruvate dioxygenase complexed with 4-hydroxylphenylpyruvic acid reveals an unexpected inhibition mechanism 被引量:1
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作者 Xiaoning Wang Hongyan Lin +5 位作者 junjun liu Xinyun Zhao Xi Chen Wenchao Yang Guangfu Yang Chang-guo Zhan 《Chinese Chemical Letters》 CSCD 2021年第6期1920-1924,共5页
4-Hydroxyphenylpyruvate dioxygenase(HPPD)is an important target for both drug and pesticide discovery.As a typical Fe(II)-dependent dioxygenase,HPPD catalyzes the complicated transformation of 4-hydroxyphenylpyruvic a... 4-Hydroxyphenylpyruvate dioxygenase(HPPD)is an important target for both drug and pesticide discovery.As a typical Fe(II)-dependent dioxygenase,HPPD catalyzes the complicated transformation of 4-hydroxyphenylpyruvic acid(HPPA)to homogentisic acid(HGA).The binding mode of HPPA in the catalytic pocket of HPPD is a focus of research interests.Recently,we reported the crystal structure of Arabidopsis thaliana HPPD(At HPPD)complexed with HPPA and a cobalt ion,which was supposed to mimic the pre-reactive structure of At HPPD-HPPA-Fe(II).Unexpectedly,the present study shows that the restored At HPPD-HPPA-Fe(II)complex is still nonreactive toward the bound dioxygen.QM/MM and QM calculations reveal that the HPPA resists the electrophilic attacking of the bound dioxygen by the trim of its phenyl ring,and the residue Phe381 plays a key role in orienting the phenyl ring.Kinetic study on the F381 A mutant reveals that the HPPD-HPPA complex observed in the crystal structure should be an intermediate of the substrate transportation instead of the pre-reactive complex.More importantly,the binding mode of the HPPA in this complex is shared with several well-known HPPD inhibitors,suggesting that these inhibitors resist the association of dioxygen(and exert their inhibitory roles)in the same way as the HPPA.The present study provides insights into the inhibition mechanism of HPPD inhibitors. 展开更多
关键词 4-Hydroxyphenylpyruvate dioxygenase QM/MM calculation Potential surface scan Substrate self-inhibition
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Ergochaeglobosins A—E, Unprecedented Heterodimers of Cytochalasan and Ergosterol from Chaeglobosin globosum P2-2-2
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作者 Xiaogang Peng junjun liu +4 位作者 Chunlun Qin Qian Wu Wanpeng Li Fatemeh Mohammadipanah Hanli Ruan 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2022年第16期1909-1916,共8页
Five novel heterodimers of cytochalasan and ergosterol,ergochaeglobosins A—E,were isolated from an endophytic fungus Chaetomium globosum P2-2-2.Ergochaeglobosin A(1) possesses an unprecedented 5/6/13/6/5/6/6/6 fused ... Five novel heterodimers of cytochalasan and ergosterol,ergochaeglobosins A—E,were isolated from an endophytic fungus Chaetomium globosum P2-2-2.Ergochaeglobosin A(1) possesses an unprecedented 5/6/13/6/5/6/6/6 fused octacyclic ring system,and ergochaeglobosins B(2) and C(3) form a unique 5/6/13/6/6/6/6/5 fused octacyclic ring system,whereas ergochaeglobosins D(4) and F(5) are the first cytochalasan heterodimers formed via a N-1′/C-3′′single bond.Their structures with absolute configurations were established by extensive spectroscopic analyses,single-crystal X-ray diffraction,and ECD calculations.The plausible biogenetic pathway of 1—5 was postulated.Compound 1 exhibited inhibitory effects against ConA-induced T cells and LPS-induced B cells proliferation with IC50 values of 19.2 and 14.1μmol/L,respectively.Co-treatment of 3(20μmol/L)with TRAIL(150 ng/mL)could significantly decrease the cell viability of A549 by 24.9%comparing with monotherapy of 3(20μmol/L). 展开更多
关键词 Cytochalasan heterodimers Natural products Biological activity Chaeglobosin globosum P2-2-2 Structure elucidation
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Boundary feedback stabilization of a Schrdinger equation interconnected with a heat equation
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作者 junjun liu Junmin WANG 《控制理论与应用(英文版)》 EI CSCD 2013年第4期558-562,共5页
In this paper, we study stabilization for a Schoedinger equation, which is interconnected with a heat equation via boundary coupling. A direct boundary feedback control is adopted. By a detailed spectral analysis, it ... In this paper, we study stabilization for a Schoedinger equation, which is interconnected with a heat equation via boundary coupling. A direct boundary feedback control is adopted. By a detailed spectral analysis, it is found that there are two branches of eigenvalues: one is along the negative real axis, and the other is approaching to a vertical line, which is parallel to the imagine axis. Moreover, it is shown that there is a set of generalized eigenfunctions, which forms a Riesz basis for the energy state space. Finally, the spectrum-determined growth condition is held and the exponential stability of the system is then concluded. 展开更多
关键词 Schroedinger equation Heat equation Boundary control STABILITY Riesz basis
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Carbonized polymer dots enhanced stability and flexibility of quasi-2D perovskite photodetector
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作者 Mingrui Tan Mingbian Li +6 位作者 Wanting Pan Xiaopeng Feng Yuhong He junjun liu Fengxia Dong Haotong Wei Bai Yang 《Light(Science & Applications)》 SCIE EI CAS CSCD 2022年第11期2716-2724,共9页
Quasi-2D perovskites have been demonstrated to be competitive materials in the photodetection fields due to the enhanced moisture stability by large organic cations.However,as the increasing demands of modern technolo... Quasi-2D perovskites have been demonstrated to be competitive materials in the photodetection fields due to the enhanced moisture stability by large organic cations.However,as the increasing demands of modern technology,it is still challenging to combine the flexibility with the capability of weak light detection in a low-cost way.Here,amides,carboxylic acids,and anhydrides groups-rich carbonized polymer dots(CPDs)were employed to fll in the perovskite grain boundaries,which can passivate the point defects of perovskite by coordinating with the unbonded Pb atoms,and reduce the leakage current.Weak light detection capability was demonstrated by directly resolving light with an intensity of 10.1 pW cm^(-2).More importantly,the stretchable polymer chains on CPDs strongly interact with perovskite ions through multiple supramolecular interactions,and extend the stretchable properties to the perovskite/CPDs composites,which can maintain the integral structure stability during the deformation of perovskite crystals and restricted any crack by releasing the flm strain.Our fabricated devices show extraordinary flexible stability in the bending-dependent response tests.The viscoelasticity of CPDs improves the bending stability of the flexible quasi-2D perovskite photodetectors,and device performance shows no degradation after bending 10000 times,comparable or even outperforming the dominating flexible photodetectors. 展开更多
关键词 PEROVSKITE STABILITY BENDING
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Chiral nanoparticle-induced amplification in optical activity of molecules with chiral centers
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作者 Lin Yang junjun liu +1 位作者 Junhong Deng Zhifeng Huang 《InfoMat》 SCIE CAS 2020年第6期1216-1224,共9页
Sensitive differentiation of an enantiomer from its mirror image(ie,enantiodifferentiation),a perennial challenge for pharmaceutical production and disease diagnosis,is technically limited by the weak optical activity... Sensitive differentiation of an enantiomer from its mirror image(ie,enantiodifferentiation),a perennial challenge for pharmaceutical production and disease diagnosis,is technically limited by the weak optical activity(OA)of enantiomers,mainly due to their dimensional mismatch with light wavelengths in the ultraviolet(UV)-visible region.Here we use silver chiral nanoparticles(Ag CNPs)with nominally sub-5 nm helical pitch(P)to amplify the OA of(20R,30R,40S)-riboflavin-50-phosphate sodium salts(RP),which have been found to indirectly affect metabolic processes,through the formation of an RP thin film(TF)covering a close-packed array of Ag CNPs.The OA of the RP in the deep-UV region can be amplified up to 80-fold,ascribed to the aggregation of RP in the TFs and the interactions between RP and the atomically chiral lattices at the CNPs'surfaces.The former contribution,not associated with the chiral Ag topographies,plays a dominant role by thickening the RP TFs,so that the observed amplification has no enantioselective dependence on the chirality of the Ag CNPs.This study extends progress in the sensitive detection of bio-enantiomers,which is highly desired for advanced bio-detection in disease diagnosis and production of single-enantiomer pharmaceuticals. 展开更多
关键词 (2'R 3'R 4'S)-riboflavin-5'-phosphate sodium salt chiral nanoparticles circular dichroism glancing angle deposition optical activity
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