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A novel cytotoxic neophysalin from Physalis alkekengi ***

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Chinese Chemical Letters 2009年第11期20卷 1327-1330页

作者： Chu Hang Zhang Zheng Tao Wang Yi Ping Yang Qi shi sun School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China Key Laboratory of Standardization of Chinese Medicines of Ministry of Education Institute of Chinese Materia Medica Shanghai University of Traditional Chinese Medicine Shanghai 201203 China

A new neophysalin, named 5α-hydroxy-25,27-dihydro-4,7-didehydro-7-deoxyneophysalin A（1）, along with three other known neophysalins （2-4） were isolated from the calyxes of Physalis alkekengi L. *** （Mast.） Makino. The structure of 1 was determined by means of 1D and 2D NMR, UV, IR and mass spectra. Compound 1 displayed potent cytotoxicities in vitro against PC- 3 and LNCaP cell lines.

关键词： Physalis alkekengi var. francheti Neophysalin Cytotoxicity

New clues concerning pigment biosynthesis in green colored fiber provided by proteomics-based analysis

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Journal of Integrative Agriculture 2018年第1期17卷 46-53页

作者： LI Yan-jun sun shi-chao ZHANG Xin-yu WANG Xiang-fei LIU Yong-chang XUE Fei sun Jie Key Laboratory of Oasis Eco-agriculture College of AgricultureShihezi University College of Pharmacy Shihezi University

To separate the proteins related to pigment synthesis in green colored fiber （GCF）, we performed a comparative proteomic analysis to identify the differentially expressed proteins between green cotton fiber and a white near-isogenic line （NIL）. One differential spot identified as phenylocumaran benzylic ether redutase-like protein （PCBER） was expressed only in GCF, but was not found in white colored fiber （WCF） at any time points. Since PCBER was a key enzyme in lignans biosynthesis, total lignans were extracted from GCF and WCF and their content was determined by using a chromotropic acid spectrophotometric method. The results showed that total lignans content in GCF was significantly higher than that in WCF. The qPCR analysis for two PLR genes associated with lignans biosynthesis showed that the expression level of two genes was much higher in GCF than that in WCF at 24 and 27 days post anthesis （DPA）, which may be responsible for the higher lignans content in GCF. Our study suggested that PCBER and lignans may be responsible for the color difference between GCF and WCF. Additionally, p-dimethylaminocinnamaldehyde （DMACA） staining demonstrated that the pigment in GCF was not proanthocyanidins, and was different from that in brown colored fiber （BCF）. This study provided new clues for uncovering the molecular mechanisms related to pigment biosynthesis in GCF.

关键词： green colored cotton proteomics upland cotton pigment biosynthesis phenylocumaran benzylic ether redutase- like protein

CeO_(x)-supported monodispersed MoO_(3) clusters for high-efficiency electrochemical nitrogen reduction under ambient condition

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Journal of Energy Chemistry 2021年第5期30卷 186-192页

作者： Jie Liu Guanghua Wang shiyuan Zhou Sangui Liu Gen Li Hong-Gang Liao shi-Gang sun State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Developing efficient and low-cost electrocatalysts is essential for the electroreduction of N_(2) to NH_(3).Here,highly monodispersed MoO_(3) clusters loaded on a coral-like CeO_(x)compound with abundant oxygen vacancies are successfully prepared by an impregnation-reduction *** MoO_(3) clusters with small sizes of 2.6±0.5 nm are induced and anchored by the oxygen vacancies of CeO_(x),resulting in excellent nitrogen reduction reaction(NRR)***,the synergistic effects between MoO_(3) and CeO_(x)lead to a further improvement of the electrochemical *** as-prepared MoO_(3)-CeO_(x)catalyst shows an NH_(3) yield rate of 32.2 μg h^(-1) mg^(-1) cat and a faradaic efficiency of 7.04%at-0.75 V(*** hydrogen electrode)in 0.01 M Dulbecco’s Phosphate Buffered ***,it displays decent electrochemical stability over 30,000 ***,the electrochemical NRR mechanism for MoO_(3)-CeO_(x)is investigated by in-situ Fourier transform infrared spectroscopy.N-H stretching,H-N-H bending,and N-N stretching are detected during the reaction,suggesting that an associative pathway is *** work provides an approach to designing and synthesizing potential electrocatalysts for NRR.

关键词： Electrochemical nitrogen reduction reaction Mo-based catalysts Monodispersed clusters Oxygen vacancies

Pollen size strongly correlates with stigma depth among Pedicularis species

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Journal of Integrative Plant Biology 2016年第10期58卷 818-821页

作者： Xiang-Ping Wang Wen-Bin Yu shi-Guo sun Shuang-Quan Huang College of Life Sciences Wuhan University Wuhan 430072China Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Mengla 666303China School of Life Sciences Central China Normal University Wuhan 430079China

Summary Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a posi-tive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species （Orobancha- ceae） in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin＇s functional hypothesis between pollen size and stigma depth.

关键词： Pedicularis phylogenetic comparative analysis pollen grain volume pollen tube growth stigma depth style length trait correlation

建构主义视域下的专业基础课程教学创新方法研究

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教育教学论坛 2024年第11期 141-144页

作者：梁伟阁郭勤勤魏平孙世岩海军工程大学兵器工程学院湖北武汉430000 海军工程大学政治理论系湖北武汉430000

专业基础课程是引导学生从力学基本原理到工程实际应用的重要桥梁,传统以教师课堂授课为中心的教学方式不利于学生工程意识的建立和实践创新能力的提高。建构主义学习理论有助于引导学生自主学习,实现对所学知识意义的主动建构。以机电... 详细信息

专业基础课程是引导学生从力学基本原理到工程实际应用的重要桥梁,传统以教师课堂授课为中心的教学方式不利于学生工程意识的建立和实践创新能力的提高。建构主义学习理论有助于引导学生自主学习,实现对所学知识意义的主动建构。以机电工程专业基础课程为例,分析了建构主义学习理论视域下传统教学方式中存在的主要问题,将建构主义学习理论与机电工程专业人才培养需求相结合,提出了一种新的课程教学创新方法,阐述了建构主义用于课程教学的课堂教育效果,并对如何加强建构主义在实际课程中的应用、推广该教学方法提出了建议。

关键词：构建主义教学教学创新机电工程专业基础课程

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微生物菌剂与植物协同修复铅污染土壤

科学技术与工程 2024年第11期24卷 4793-4799页

作者：韩冰周丽鹏姚文利徐佳婷董莉莉张明孙世梅吉林建筑大学事故预防研究院长春130118 吉林建筑大学松辽流域水环境教育部重点实验室长春130118

为了有效修复和美化污染的土壤环境,降低重金属的污染,将培养生物菌剂与2种富集植物联合修复铅(Pb)污染的土壤,通过微生物培养、高效液相色谱、微生物群落多样性分析等方法,研究土壤中重金属残留、酶活性、叶绿素含量、重金属抗性菌、... 详细信息

为了有效修复和美化污染的土壤环境,降低重金属的污染,将培养生物菌剂与2种富集植物联合修复铅(Pb)污染的土壤,通过微生物培养、高效液相色谱、微生物群落多样性分析等方法,研究土壤中重金属残留、酶活性、叶绿素含量、重金属抗性菌、微生物数量和群落多样性。结果表明:Pb污染浓度为400 mg/kg,分别经过联合修复30 d和60 d,土壤中重金属浓度分别下降了19.61%、19.48%,60 d比30 d吸附率分别提高了16.82%、17.83%。过氧化氢酶由对照组的5.6 mg/kg增加到11.4、15.9 mg/kg;碱性磷酸酶的活性由45.6 mg/kg增加到88.4、93.4 mg/kg;蔗糖酶的活性由4.2 mg/kg增加到9.6、9.9 mg/kg;脲酶的活性由32.6 mg/kg增加到66.3、71.2 mg/kg。叶绿素的含量分别增加9.16%、9.18%。重金属抗性菌检出量分别减少21.31%和20.27%。细菌、真菌和放线菌的数量最高增加了97.68%、67.63%、210.09%。微生物群落多样性和丰度也相应增加2.7%、2.9%。可见污染土壤经过微生物菌剂与植物联系修复后,植物的光合作用增强,加快重金属的吸附和转运,提高酶活性,提升植物对重金属的耐受性,重金属抗性菌数量显著降低,微生物群落多样性增加;阐明微生物菌剂和植物协同作用下对重金属污染土壤的强化修复机制,为高效治理土壤污染提供科学依据。

关键词：污染土壤重金属生态修复重金属抗性菌微生物多样性

Photoacoustic elastography based on laser-excited shear wave

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Journal of Innovative Optical Health Sciences 2024年第3期17卷 56-72页

作者： Yang Liu Ruoyi shi Gang Li Mingjian sun School of Astronautics Harbin Institute of TechnologyHarbin 150000P.R.China School of Information Science and Engineering Harbin Institute of TechnologyWeihai 264200P.R.China

Elastography can be used as a diagnostic method for quantitative characterization of tissue hardness information and thus,differential changes in pathophysiological states of *** this study,we propose a new method for shear wave elastography(SWE)based on laser-excited shear wave,called photoacoustic shear wave elastography(PASWE),which combines photoacoustic(PA)technology with ultrafast ultrasound *** using a focused laser to excite shear waves and ultrafast ultrasonic imaging for detection,high-frequency excitation of shear waves and noncontact elastic imaging can be *** laser can stimulate the tissue with the light absorption characteristic to produce the thermal expansion,thus producing the shear *** frequency of shear wave induced by laser is higher and the frequency band is *** tracking the propagation of shear wave,Young’s modulus of tissue is reconstructed in the whole shear wave propagation region to further evaluate the elastic information of *** feasibility of the method is verified by *** with the experimental results of supersonic shear imaging(SSI),it is proved that the method can be used for quantitative elastic imaging of the *** addition,compared with the SSI method,this method can realize the noncontact excitation of the shear wave,and the frequency of the shear wave excited by the laser is higher than that of the acoustic radiation force(ARF),so the spatial resolution is *** to the traditional PA elastic imaging method,this method can obtain a larger imaging depth under the premise of ensuring the imaging resolution,and it has potential application value in the clinical diagnosis of diseases requiring noncontact quantitative elasticity.

关键词： Elastography shear wave photoacoustic Young's modulus

A novel snowdrift game model with edge weighting mechanism on the square lattice

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Frontiers of physics 2012年第3期7卷 366-372页

作者： Juan-uan Zhang Hong-yun Ning Zi-yu Yin shi-wen sun Li Wang Jun-qing sun Cheng-yi Xia Tianjin Key Laboratory of Intelligence Computing and Novel Softwave Technology Tianjin University of Technology Tianjin 300384China Key Laboratory of Computer Vision and System of Ministry of Education Tianjin University of TechnologyTianjin 300384China School of Physics Nankai UniversityTianjin 300071China

We propose a novel snowdrift game model with edge weighting mechanism to explore the cooperative behaviors among the players on the square lattice. Based on the assumption of three types of weight distribution including uniform, exponential and power-law schemes, the cooperation level is largely boosted in contrast with the traditional snowdrift game on the unweighted square lattice. Exten- sive numerical simulations indicate that the fraction of cooperators greatly augments, especially for the intermediate range of cost-to-benefit ratio r. Furthermore, we investigate how the cooperative behaviors are affected by the undulation amplitude of weight distribution and noise strength of strat- egy selection, respectively. The simulation results will be conducive to further understanding and analyzing the emergence of cooperation, which is a ubiquitous phenomenon in social and biological science.

关键词： snowdrift game edge weighting mechanism cooperative dynamics

Microstructure,Mechanical Properties and Fracture Behavior of As-Extruded Zn-Mg Binary Alloys

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 931-940页

作者： Li-Qing Wang Yu-Ping Ren shi-Neng sun Hong Zhao Song Li Gao-Wu Qin Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) School of Materials Science and EngineeringNortheastern University

In the present work, Zn-（0-1）Mg（wt%） alloys were prepared by casting and indirect extrusion at 200 and300 ℃, respectively. With Mg addition, both the size and amount of second phase Mg2Zn（11） increased, and the equiaxed grains were significantly refined. The extrusion temperature had little influence on Mg2Zn（11）, but the grains were refined at low extrusion temperature. For the alloys extruded at 200 ℃, as Mg content increased, the tensile yield strength（TYS）increased from 64 MPa for pure Zn to 262 MPa for Zn-1Mg; the elongation increased from 14.3% for pure Zn to 25% for Zn-0.02Mg and then decreased to 5% for Zn-1Mg. For the alloys extruded at 300 ℃, as Mg content increased, the TYS increased from 67 MPa for pure Zn to 252 MPa for Zn-1Mg, while the elongation decreased from 11.7% to 2%. The alloy extruded at 200 ℃ exhibited higher TYS and elongation than the corresponding alloy extruded at 300 ℃. The combination of grain refinement and second phase Mg2Zn（11） contributed to the improvement in the TYS, and the grain refinement played a major role in strengthening alloy. Zn-0.02Mg and Zn-0.05Mg alloys extruded at 200 ℃ show a mixture of cleavage and ductile fracture corresponding to higher elongation, while the other alloys show cleavage fracture.

关键词： Zn-Mg binary alloy Indirect extrusion Microstructure Mechanical property Fracture behavior