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改进的v-支持向量回归机的v解路径算法

系统工程与电子技术 2016年第1期38卷 205-214页

作者：顾斌杰潘丰江南大学轻工过程先进控制教育部重点实验室江苏无锡214122

v-支持向量回归机(v-support vector regression,v-SVR)的对偶形式与ε-支持向量回归机的对偶形式相比增加了一个额外的不等式约束,截止目前还没有找到有效且可行的v-SVR的v解路径算法。针对Loosli等人提出的v-SVR的v解路径算法存在路... 详细信息

v-支持向量回归机(v-support vector regression,v-SVR)的对偶形式与ε-支持向量回归机的对偶形式相比增加了一个额外的不等式约束,截止目前还没有找到有效且可行的v-SVR的v解路径算法。针对Loosli等人提出的v-SVR的v解路径算法存在路径不可更新的问题,提出了改进的v-SVR的v解路径算法。该算法基于v-SVR的修改形式及Karush-Kuhn-Tucker(KKT)条件,通过引入新的变量和附加项的策略,能够有效地避免在绝缘增量调整过程中存在的冲突和异常,并最终经过有限次数迭代拟合出整个v解路径。理论分析和仿真结果表明,该算法是有效且可行的。

关键词：机器学习模型选择 v-支持向量回归机 v解路径

Isolated supramolecules on surfaces studied with scanning tunneling microscopy

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Chinese Chemical Letters 2016年第6期27卷 807-812页

作者： Chao Xie Qi-Meng Wu Ruo-Ning Li Gao-Chen gu Xue Zhang Na Li Richard Berndt Jorg Kroger Zi-Yong Shen Shi-Min Hou Yong-feng Wang Key Laboratory for the Physics and Chemistry of Nanodevices Department of ElectronicsPeking UniversityBeijing 100871China Department of Environmental Science College of Environment and ResourcesJilin UniversityChangchun 130021China College of Electronic Science and Engineering Jilin UniversityChangchun 130021China Institut fur Experimentelle und Angewandte Physik Christian-Albrechts-Universita't zu KielD-24098 KielGermany Institut fur Physik Technische Universita't IlmenauD-98693 IlmenauGermany Beida Information Research(BIR) Tianjin 300457China

To date, supramolecular chemistry is an ever growing research field owing to its crucial role in molecular catalysis, recognition, medicine, data storage and processing as well as artificial photosynthetic *** isolated supramolecules were prepared by molecular self-assembly on surfaces. This review mainly focuses on supramolecular aggregations on noble metal surfaces studied by scanning tunneling microscopy, including dimers, trimers, tetramers, pentamers, wire-like assemblies and Sierpin′ ski triangular fractals. The variety of self-assembled structures reflects the subtle balance between intermolecular and molecule–substrate interactions, which to some extent may be controlled by molecules, substrates and the molecular coverage. The comparative study of different architectures helps identifying the operative mechanisms that lead to the structural motifs. The application of these mechanisms may lead to novel assemblies with tailored physicochemical properties.

关键词： Supramolecular aggregations Scanning tunneling microscope(STM) Weak interactions Self-assembly Fractal Sierpinski triangle

Pressure Induced Phase Transition in TiB

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Chinese Physics Letters 2001年第9期18卷 1240-1241页

作者： LI feng-Ying CHEN Liang-Chen WANG Li-Jun gu Hui-Cheng WANG Ru-Ju CHE Rong-Zheng SHEN Zhong-Yi Institute of Physics Chinese Academy of SciencesBeijing 100080

In situ high pressure x-ray diffraction and electrical resistance experiments on TiB have been carried out by using a diamond anvil cell device. The results revealed that the sample undergoes a first-order phase transition at pressures of 3.5-5.0 Gpa and 4.0-5.5 Gpa for the x-ray diffraction and electrical resistance experiments, respectively. The parameters of the state equation are calculated before and after the phase transition and compared with the values calculated by Mohn et al. [J. Phys. C: Solid State Phys. 21(1988)2829] using the augmented spherical wave method.

关键词： resistance Transition transition

Analysis of clinical risk factors associated with mortality of severely injured multiple trauma patients with acute lung injury

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Chinese Medical Journal 2009年第6期122卷 701-705页

作者： MA Yue-feng SHENG Lei gu Jun ZHANG Mao JIANG guan-yu Emergency Department Second Affiliated Hospital of Zhejiang University School of Medicine Hangzhou Zhejiang 310009 China Nursing Faculty of Zhejiang Medical College Hangzhou Zhejiang 310053 China Department of Orthopedics Red Crossing Hospital Hangzhou Zhejiang 310003 China

Background It is important to study the factors affecting the clinical mortality of the severe multiple trauma population. The present study was aimed to identify the potential risk factors that could affect mortality rate of acute lung injury （ALl） in severely injured multiple trauma population and to investigate the effects of certain risk factors on the prognosis of different patient subpopulations.Methods This is a follow-up study treating trauma as a single cause for emergency department （ED） and emergency intensive care unit （EICU） admissions. Patients identified with severe multiple trauma with early onset of ALl were enrolled from five trauma centers. Nineteen potential risk factors affecting the prognosis of ALl were examined by univariate and multivariate Logistic regression analyses to identify the ones that affected the mortality of these severe multiple trauma patients.Results There were 687 multiple trauma patients with post-traumatic ALl admitted to ED and EICU during the study period. The six risk factors that affected the mortality with unadjusted odd ratios （ORs） and 95% confidence intervals （C/s） were Acute Physiology Score and Chronic Health Evaluation Score （APACHE） II score, Injury Severity Score （ISS）, duration of trauma, age, aspiration of gastric contents, and disseminated intravascular coagulation （DIC）. Specific risk factors also affected different patient subpopulations at different degrees （surviving beyond 24 hours, 72 hours, 28 days and with multiple blood transfusions and higher injury scores）.Conclusions Factors of APACHE II score, ISS and aspiration of gastric contents that could predict the morality of AL may exist in the early stage of trauma. Duration of trauma long-term development and mortality of ALl deserve special and DIC that greatly affected and predicted the short- and attention. Elderly patients （aged beyond 65 years） were the independent risk factor for the secondary sepsis and deterioration of pulmonary function.

关键词： trauma acute lung injury mortality APACHE H analysis

MiR-1180 from bone marrow-derived mesenchymal stem cells induces glycolysis and chemoresistance in ovarian cancer cells by upregulating the Wnt signaling pathway

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2019年第3期20卷 219-237页

作者： Zhuo-wei gu Yi-feng HE Wen-jing WANG Qi TIAN Wen DI Department of Obstetrics and Gynecology Ren Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Shanghai Key Laboratory of Gynecologic Oncology Ren Ji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China

Background:Bone marrow-derived mesenchymal stem cells(BM-MSCs)play an important role in cancer development and ***,the mechanism by which they enhance the chemoresistance of ovarian cancer is ***:Conditioned media of BM-MSCs(BM-MSC-CM)were analyzed using a technique based on microRNA *** most highly expressed microRNAs were selected for testing their effects on glycolysis and chemoresistance in SKOV3 and COC1 ovarian cancer *** targeted gene and related signaling pathway were investigated using in silico analysis and in vitro cancer cell ***-Merier survival analysis was performed on a population of 59 patients enrolled to analyze the clinical significance of microRNA findings in the prognosis of ovarian ***:MiR-1180 was the most abundant microRNA detected in BM-MSC-CM,which simultaneously induces glycolysis and chemoresistance(against cisplatin)in ovarian cancer *** secreted frizzled-related protein 1(SFRP1)gene was identified as a major target of *** overexpression of miR-1180 led to the activation of Wnt signaling and its downstream components,namely Wnt5 a,β-catenin,c-Myc,and CyclinD1,which are responsible for glycolysis-induced *** miR-1180 level was inversely correlated with SFRP1 mRNA expression in ovarian cancer *** overexpressed mi R-1180 was associated with a poor prognosis for the long-term(96-month)survival of ovarian cancer ***:BM-MSCs enhance the chemoresistance of ovarian cancer by releasing *** released miR-1180 activates the Wnt signaling pathway in cancer cells by targeting *** enhanced Wnt signaling upregulates the glycolytic level(*** effect),which reinforces the chemoresistance property of ovarian cancer cells.

关键词： Chemoresistant ovarian cancer Mesenchymal stem cell MiR-1180 Secreted frizzled-related protein 1(SFRP1) Wnt Glycolysis

Fast tracking alien gene discovery by molecular markers in a late flowering Chinese cabbage-cabbage translocation line‘AT7–4'

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Horticultural Plant Journal 2023年第1期9卷 89-97页

作者： Hui Li Aixia gu Daling feng Na Li Rui Yang Xinpei Zhang Shuangxia Luo Umer Karamat Qianyun Wang Shuxin Xuan Xueping Chen Yin Lu Yanhua Wang Shuxing Shen Jianjun Zhao State Key Laboratory of North China Crop Improvement and Regulation Key Laboratory of Vegetable Germplasm Innovation and Utilization of HebeiCollaborative Innovation Center of Vegetable Industry in HebeiBaodingHebei 071000China College of Horticulture Hebei Agricultural UniversityBaodingHebei 071000China College of Life Science Hebei Agricultural UniversityBaodingHebei 071000China

Flowering time is an important agronomic trait of Chinese cabbage with late flowering being a primary breeding *** our previous work,we obtained Chinese cabbage-cabbage translocation lines that contained several beneficial cabbage ***-specific molecular markers show that these genes were coming from chromosome C01 of *** this study,we investigated the inheritance of flowering time in a couple of translocation lines and analyzed the transmission rate of molecular markers in the ***,we obtained the late flowering Chinese cabbage-cabbage translocation line‘AT7–4’in which the flowering time was later than that of‘85–1’by about 7 days under 4-week *** on previous studies of the genomes of Chinese cabbage and cabbage,we located the cabbage-specific molecular markers that were closely linked at the top of the chromosome A01 in the F2mapping population generated by self-crossing F1s derived from a cross between the translocation line‘AT7–4’and Chinese cabbage‘14–36’.Five flowering-related genes in the alien fragment were found by functional annotation and their molecular markers were *** study lays the foundation for the future improvement of Chinese cabbage varieties using A-C translocation lines.

关键词： Chinese cabbage Translocation line Alien gene Molecular marker Late flowering

构筑苯乙烯轴手性——高效的醛亚胺临时导向基

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有机化学 2020年第6期40卷 1787-1789页

作者：冯佳顾振华中国科学技术大学化学系合肥微尺度物质科学国家研究中心合肥230026

轴手性结构是一些催化剂和配体的优势骨架,其在材料化学中的应用也越来越受到重视.轴手性结构也广泛地存在于天然产物、生理活性药物之中.轴手性化合物不仅表现出不同的生理活性,有时还展现出对不同受体的选择性.

关键词：轴手性天然产物醛亚胺材料化学催化剂苯乙烯生理活性配体

基于顶空气相色谱-离子迁移谱的不同品种香稻米快速鉴别方法

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食品研究与开发 2024年第4期45卷 164-171页

作者：卞景阳孙兴荣刘琳帅邵凯冯鹏车野胡禧熙顾鑫徐磊李杰黑龙江省农业科学院大庆分院黑龙江大庆163319 国家耐盐碱水稻技术创新中心东北中心黑龙江哈尔滨163316

采用气相色谱-离子迁移谱(gas chromatography-ion mobility spectrometry,GC-IMS)技术原理,分析“牡育稻78号”、“牡科稻5号”、“牡科稻7号”3种香稻米中挥发性成分的组成,结合主成分分析(principal component analysis,PCA)进行统计分析。结果发现:辛醛单体、辛醛二聚体、6-甲基-5-庚烯-2-酮在“牡科稻5号”中含量最少,在其它样品中差异不大;罗勒烯、柠檬烯单体、柠檬烯二聚体在“牡育稻78号”中含量最多;乙醇、二甲基-1-丁醇在“牡科稻7号”中含量最多。主成分分析表明,不同品种香稻米挥发性气味成分在气相色谱-离子迁移谱上呈现出一定差异,两个主成分累计贡献率达到84%,说明基于GC-IMS技术可以实现不同品种香稻米的区分。

关键词：指纹图谱气相色谱-离子迁移谱特征风味香稻米挥发性成分

Hydrothermal synthesis and energy storage performance of ultrafine Ce2Sn2O7 nanocubes

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Journal of Central South University 2019年第6期26卷 1416-1425页

作者： HUO Yi-feng QIN Ning LIAO Cheng-zhu feng Hui-fen gu Ying-ying CHENG Hua Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Hunan Provincial Key Laboratory of Chemical Power Sources Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese ResourcesCollege of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China

Ultrafine cube-shape Ce2Sn2O7 nanoparticles crystallized in pure pyrochlore phase with a size of about 10 nm have been successfully synthesized by a facile hydrothermal *** experiments have been conducted to optimize the processing parameters including temperature,pH,reaction duration,precipitator types to obtain phase-pure *** crystal structure,morphology and sizes and specific surface area have been characterized by X-ray diffractometer(XRD),Raman spectrum,transmission electron microscope(TEM),high resolution transmission electron microscope(HRTEM),and Brunauer-Emmett-Teller(BET).The as-synthesized Ce2Sn2O7 ultrafine nanocubes have been evaluated as electrode materials for pseudo-capacitors and lithium ion *** testing as supercapacitors,a high specific capacitance of 222 F/g at 0.1 A/g and a good cycling stability with a capacitance retention of higher than 86%after 5000 cycle have been *** targeted for anode material for lithium ion batteries,the nanocubes deliver a high specific reversible capacity of more than 900 mA·h/g at 0.05C *** rate capability and cycling performance is also very promising as compared with the traditional graphite anode.

关键词： supercapacitors lithium ion batteries composite oxides ultrafine nanoparticles hydrothermal pyrochlore