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The Number of Circles of a Maximum State of a Plane Graph with Applications

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Acta Mathematicae Applicatae Sinica 2021年第2期37卷 409-420页

作者： xian-an JIN Jun GE Xiao sheng CHENG yu-qing LIN School of Mathematical Sciences Xiamen UniversityXiamen 361005 China School of Mathematical Sciences&Laurent Mathematics Center Sichuan Normal UniversityChengdu610066China School of Mathematics and Statistics Huizhou UniversityHuizhouGuangdong 516007China School of Electrical Engineering and Computer Science The Univesity of NewcastleCallaghanNSW 2308Australia

Motivated by the connection with the genus of the corresponding link and its application on DNA polyhedral links,in this paper,we introduce a parameter s_(max)(G),which is the maximum number of circles of states of the link diagram D(G)corresponding to a plane(positive)graph *** show that s_(max)(G)does not depend on the embedding of G and if G is a 4-edge-connected plane graph then s_(max)(G)is equal to the number of faces of G,which cover the results of *** and *** as special cases.

关键词： plane graph number of circles special alternating link genus DNA polyhedral link

Understanding micro-diffusion bonding from the fabrication of B_4C/Ni composites

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 365-374页

作者： Miao Wang Wen-xian Wang Hong-sheng Chen yu-li Li College of Materials Science and Engineering Taiyuan University of Technology Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology

A Ni-B_4C macroscopic diffusion welding couple and a Ni-15 wt% B_4C composite fabricated by spark plasma sintering(SPS) were used to understand the micro-scale diffusion bonding between metals and ceramics. In the Ni-B_4C macroscopic diffusion welding couple a perfect diffusion welding joint was achieved. In the Ni-15 wt% B_4C sample, microstructure analyses demonstrated that loose structures occurred around the B_4C particles. Energy dispersive X-ray spectroscopy analyses revealed that during the SPS process, the process of diffusion bonding between Ni and B_4C particles can be divided into three stages. By employing a nano-indentation test, the room-temperature fracture toughness of the Ni matrix was found to be higher than that of the interface. The micro-diffusion bonding between Ni and B_4C particles is quite different from the Ni-B_4C reaction couple.

关键词： B4C/Ni composites spark plasma sintering micro-diffusion welding microstructure nano-mechanical property

Synthesis and Crystal Structure of Pd(AETYF)Cl_2CH_2Cl_2 [AETYF = 4'5'Diaza-9' (4,5-bis(ethylthio)-1,3-dithiole-2-ylidene)-fluorene]

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Chinese Journal of Structural Chemistry 2004年第6期23卷 551-554页

作者： ZHUQin-yu DAIJie ZHANGYong JIADing-xian ZHANGJia-sheng GUOLing DepartmentofChemistryandChemicalEngineering SuzhouUniversitySuzhou215006China StateKeyLaboratoryofCoordinationChemistry CoordinationChemistryInstituteNanjingUniversityNanjing210093China

A stable Pd(II) compound Pd(AETYF)Cl2CH2Cl2 (AETYF = 4?5?diaza-9? (4,5-bis(ethylthio)-1,3-dithiole-2-ylidene)-fluorene) has been synthesized and its crystal structure was determined by X-ray crystallography. The crystal is of monoclinic, space group P21/c with a = 15.249(6), b = 8.619(3), c = 19.078(7) ? b = 106.932(8), C19H18Cl4N2PdS4, Mr = 650.79, V = 2398.6(16) 3, Z = 4, Dc = 1.802 g/cm3, F(000) = 1296, m = 1.579 mm-1, Npar = 268, the final R = 0.0538 and wR = 0.1282 for 5068 observed reflections with I > 2s(I). The crystal structure determi- nation shows that the atoms of the molecule, except two ethyl-groups, are conjugated in a quasi- plane and these molecules are further stacked or contacted via plane to plane or edge to edge p-p interactions, forming parallel molecular chains along the b axis.

关键词： diaza-fluorene palladium complex crystal structure intermolecular interaction

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疤痕消涂膜剂透皮吸收的研究

时珍国医国药 2003年第6期14卷 321-322页

作者：孟宪生王玉珍陈再兴辽宁中医学院辽宁中医学院辽宁沈阳110032

目的 :研究不同浓度月桂氮酮对透皮吸收的影响。方法 :采用紫外分光光度法 ,在波长 (2 66± 2 )nm ,测定不含月桂氮酮 ,含 1.0 %、2 .0 %月桂氮酮的疤痕消涂膜剂的体外透皮吸收溶液吸光度。结果 :不同浓度月桂氮酮的涂膜剂的体外透皮吸... 详细信息

目的 :研究不同浓度月桂氮酮对透皮吸收的影响。方法 :采用紫外分光光度法 ,在波长 (2 66± 2 )nm ,测定不含月桂氮酮 ,含 1.0 %、2 .0 %月桂氮酮的疤痕消涂膜剂的体外透皮吸收溶液吸光度。结果 :不同浓度月桂氮酮的涂膜剂的体外透皮吸收溶液吸光度不同 ,同一浓度月桂氮酮的涂膜剂的体外透皮吸收溶液与时间变化成线性关系。结论 :含 1.0 %月桂氮酮的涂膜剂药物透皮吸收显著

关键词：疤痕消涂膜剂月桂氮酮透皮吸收

Steric Hindrance Ligand Strategy to Aluminum Porphyrin Catalyst for Completely Alternative Copolymerization of CO_2 and Propylene Oxide

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Chinese Journal of Polymer Science 2018年第2期36卷 252-260页

作者： Chun-Wei Zhuo yu-sheng Qin xian-Hong Wang Fo-Song Wang Key Laboratory of Polymer Ecomaterial Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

Aluminum porphyrin complexes are heavy-metal-free and soil-tolerant green catalysts for the copolymerization of CO2 and propylene oxide（PO）, but they suffer from relatively poor poly（propylene carbonate）（PPC） selectivity. Herein, steric hindrance porphyrin ligand was used to enhance the PPC selectivity. Typically, a bulky anthracene-like group was incorporated into the porphyrin ring to form 5,10,15,20-tetra（1,2,3,4,5,6,7,8-octahydro-1,4：5,8-dimethanoanthracen-9-yl）porphyrin, the aluminum porphyrin complex with this ligand, in combination with bis（triphenylphosphine）iminium chloride as a co-catalyst, produced completely alternate PPC. Additionally, the obtained PPC showed high regioselectivity, with a head-to-tail linkage content（HT） of 92%. Therefore, we demonstrated that introduction of bulky steric ligand into the porphyrin ring could reduce the propylene oxide homopolymerization activity leading to excellent PPC selectivity, and improve regioselectivity for the PO ring-opening during the copolymerization.

关键词： Carbon dioxide Propylene oxide Porphyrin Aluminum Steric hindrance

Laparoscopic pancreaticoduodenectomy with portal or superior mesenteric vein resection and reconstruction for pancreatic cancer:A single-center experience

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Hepatobiliary & Pancreatic Diseases International 2023年第2期22卷 147-153页

作者： Ming-Jian Ma He Cheng yu-sheng Chen xian-Jun yu Chen Liu Department of Pancreatic Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Shanghai Pancreatic Cancer Institute Shanghai 200032China Pancreatic Cancer Institute Fudan UniversityShanghai 200032China

Background: Open pancreaticoduodenectomy(OPD) with portal or superior mesenteric vein resection and reconstruction has been applied in pancreatic cancer patients with tumor infiltration or adherence. However, it is controversial whether laparoscopic pancreaticoduodenectomy(LPD) with major vascular resection and reconstruction is feasible. This study aimed to evaluate the safety and feasibility of LPD with major vascular resection compared with OPD with major vascular resection. Methods: We reviewed data for all pancreatic cancer patients undergoing LPD or OPD with vascular resection at Department of Pancreatic Surgery, Fudan University Shanghai Cancer Center, between February 2018 and May 2022. We compared the preoperative, intraoperative, and postoperative clinicopathological data of the two groups to conduct a comprehensive evaluation of LPD with major vascular resection. Results: A total of 63 patients underwent pancreaticoduodenectomy(PD) with portal or superior mesenteric vein resection and reconstruction, including 25 LPDs and 38 OPDs. The LPD group had less intraoperative blood loss(200 vs. 400 m L, P < 0.001), lower proportion of intraoperative blood transfusion(16.0% vs. 39.5%, P = 0.047), longer operation time(390 vs. 334 min, P = 0.004) and shorter postoperative hospital stay(11 vs. 14 days, P = 0.005). There was no perioperative death in all patients. There was no significant difference in the incidence of total postoperative complications, grade B/C postoperative pancreatic fistula, delayed gastric emptying and abdominal infection between the two groups. No postpancreatectomy hemorrhage nor bile leakage occurred during perioperative period. There was no significant difference in R0 resection rate and number of lymph nodes harvested between the two groups. Patency of reconstructed vessels in the two groups were 96.0% and 92.1%, respectively( P = 0.927). Conclusions: LPD with portal or superior mesenteric vein resection and reconstruction was safe, feasib

关键词： Laparoscopy Pancreaticoduodenectomy Whipple procedure Mesenteric veins Portal vein Pancreatic neoplasms

CO_2-sensitive Amphiphilic Triblock Copolymer Self-assembly Morphology Transition and Accelerating Drug Release from Polymeric Vesicle

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Chinese Journal of Polymer Science 2018年第1期36卷 18-24页

作者： xian-Wu Jing Zhi-yu Huang Hong-sheng Lu Bao-Gang Wang College of Chemistry and Chemical Engineering Southwest Petroleum University Engineering Research Center of Oilfield Chemistry Ministry of Education

A series of triblock copolymers, containing a CO_2-switchable block poly（2-（dimethylamino）ethyl methacrylate）（PDM） block and two symmetrical hydrophilic blocks polyacrylamide（PAM）, were synthesized using atom transfer radical polymerization（ATRP） method. The p H and conductivity tests showed that the triblock copolymer exhibited switchable responsiveness to CO_2, i.e. a relatively low conductivity of solution could be switched on and off by bubbling and removing of CO_2, and the triblock copolymer aqueous solution displayed a CO_2-switchable viscosity variation. The changes were all attributed to protonation of tertiary amine groups in PDM blocks and proven by 1 H-NMR. Cryogenic transmission electron microscopy and dynamic light scattering characterization demonstrated that the viscosity variation was the result of a unilamellar vesicle-network aggregate structure transition. The release of rhodamine B from the vesicles with and without CO_2 stimuli showed the potential application in drug delivery domains; after CO_2 bubbling, the drug release rate could be accelerated. Finally, reasonable mechanism of CO_2-switchable morphology changes and CO_2-induced drug release was proposed.

关键词： ATRP CO_2-sensitive Polymeric vesicles Drug release

甲状腺乳头状癌患者血清维生素D水平与疾病进展及预后的相关性研究

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中国卫生检验杂志 2018年第5期28卷 635-637,640页

作者：盛贤能郭宇章佳波王金秋鲁杨宁波市第一医院甲状腺乳腺外科浙江宁波315000 宁波大学医学院甲状腺乳腺外科浙江宁波315000

目的探讨甲状腺乳头状癌(PTC)患者血清维生素D水平与疾病进展及预后的相关性。方法选取92例PTC患者为研究对象,另选取同期健康体检者40例为对照组,比较2组血清维生素D水平及PTC患者疾病和预后情况,分析血清维生素D与PTC疾病进展及预后... 详细信息

目的探讨甲状腺乳头状癌(PTC)患者血清维生素D水平与疾病进展及预后的相关性。方法选取92例PTC患者为研究对象,另选取同期健康体检者40例为对照组,比较2组血清维生素D水平及PTC患者疾病和预后情况,分析血清维生素D与PTC疾病进展及预后的关系。结果血清维生素D与肿瘤浸润深度、分期呈负相关(r值分别为-0.328、-0.286,P<0.05),与肿瘤分化呈正相关(r=0.306,P<0.05);血清维生素D水平、肿瘤浸润深度、淋巴结转移、肿瘤分期、大小、分化程度以及数目均为影响PTC患者预后的相关因素(P<0.05);维生素D缺乏、淋巴结转移、肿瘤低分化和Ⅲ期~Ⅳ期肿瘤是影响PTC患者预后的独立危险因素(P<0.05)。结论血清维生素D缺乏可加速PTC疾病的进展,并为影响PTC患者预后的独立危险因素。

关键词：甲状腺乳头状癌血清维生素D 疾病进展预后相关性

Expression Analysis of Dihydroflavonol 4-Reductase Genes Involved in Anthocyanin Biosynthesis in Purple Grains of Wheat

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Journal of Integrative Plant Biology 2005年第9期47卷 1107-1114页

作者： Mao-Sen LIU Fang WANG yu-Xiu DONG xian-sheng ZHANG Shandong Key Laboratory of Crop Biology College of Life Sciences Shandong Agricultural University Taian Shandong 271018 China

The grain color of wheat （Triticum aestivum L.） is an important characteristic in crop production. Dihydroflavonol 4-reductase genes （DFR） encode the key enzyme dihydroflavonol 4-reductase, which is involved in the pigmentation of plant tissues. To investigate the molecular mechanism of anthocyanin deposition in grains of wheat, we determined the expression of the wheat DFR gene in purple grains of cultivar Heimai 76. The results showed that DFR transcripts were localized in the seed coat of purple grains rather than in the pericarp, whereas anthocyanins were accumulated in both tissues of purple grains, suggesting that anthocyanin deposition was mainly regulated at the transcriptional level. Overexpression of the TaDFR-A gene in Arabidopsis showed that TaDFR-A was responsible for the pigmentation of Arabidopsis plant tissues, indicating TaDFR-A gene has the same role in Arabidopsis.

关键词： anthocyanin dihydroflavonol 4-reductase localization of TaDFR transcripts purple grain wheat.