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Permeation of dimethyl sulfoxide into articular cartilage at subzero temperatures

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第3期13卷 213-220页

作者： Shao-zhi ZHANG xiao-yi yu Guang-ming CHEN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Osteochondral allografting has been proved to be a useful method to treat diseased or damaged areas of joint surfaces. Operational long-term stocks of grafts which supply a buffer between procurement and utilization would contribute to the commercialization or industrialization of this technology. Vitrification has been thought to be a promising method for successful preservation of articular cartilage （AC）, but high concentration cryoprotectants （CPAs） are used which may cause high cellular toxicity. An effective way to reduce CPA toxioity is to increase CPA concen- tration gradually while the temperature is lowered. Understanding the mechanism of （31~A permeation at subzero temperatures is important for designing the cryopreservation protocol. In this research, the permeation of dimethyl sulfoxide （MezSO） in ovine AC at subzero temperatures was studied experimentally. Pretreated AC discs were ex- posed in Me2SO solutions for different time （0, 5, 15, 30, 50, 80, and 120 min） at three temperature levels （-10, -20, and -30℃）. The Me2SO concentration within the tissue was determined by ultraviolet （UV） spectrophotometry. The diffusion coefficients were estimated to be 0.85×10-6, 0.48×10-8, and 0.27×10-6 cm2/s at -10, -20, and -,30℃, respectively, and the corresponding activation energy was 29.23 kJ/mol. Numerical simulation was performed to com- pare two Me2SO addition protocols, and the results demonstrated that the total loading duration could be effectively reduced with the knowledge of permeation kinetics.

关键词： Articular cartilage Vitrification Dimethyl sulfoxide Permeation Diffusion coefficient Subzero temperature

Influence of high energy ball milling on Al-30Si powder and ceramic particulate

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中国有色金属学会会刊：英文版 2000年第3期10卷 324-327页

作者： LI yuan yuan(李元元) ZHANG Da tong(张大童) xiao zhi yu(肖志宇) S China Univ Technol Mech & Elect Dept Guangzhou 510641 Peoples R China

The influence of high energy ball milling on Al 30Si powder and ceramic particulate SiC was studied by means of SEM, XRD and DSC. The results show that Al 30Si powder and their microstructure are obviously refined after high energy ball milling process. The alloy powder and SiC p stick closely to each other without interfacial reaction. DSC results detect no reaction but relaxation of the samples. So high energy ball milling can be used as an effective method for ceramic particulate pre treatment in the fabrication of MMC.

关键词： high energy ball milling interfaces Al 30Si powders ceramic powders

Effects of plant density on cotton yield components and quality

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Journal of Integrative Agriculture 2016年第7期15卷 1469-1479页

作者： zhi xiao-yu HAN Ying-chun LI Ya-bing WANG Guo-ping DU Wen-li LI xiao-xin MAO Shu-chun FENG Lu Institute of Cotton Research Chinese Academy of Agricultural Sciences/State Key Laboratory of Cotton Biology

Yield and ifber quality of cotton even varies within locules in a bol, but it is not clear how yield components and quality parameters are altered across seed positions of a locule （SPL）. A ifeld experiment was arranged in a split plot design with transgenic insect resistant Bt （Bacilus thuringiensis） cotton hybrid cultivar CRI75 and conventional cultivar SCRC28 as the main plots, and three plant densities （15000, 51000 and 87000 plants ha–1） as the subplots in 2012 and 2013 at Anyang, Henan Province, China. Cotton was hand harvested by node and fruiting position, and then seeds of the ifrst fruiting posi-tion bols from nodes 6–10 were separated by SPL. The effects of plant density on lint yield, ifber quality, especialy across SPL were determined. It was showed that plant densities of 51000 and 87000 plants ha–1 increased lint yield by 61.3 and 65.3% in 2012 and 17.8 and 15.5% in 2013 relative to low plant density （15000 plants ha–1）, however, no signiifcant differ-ence was observed between 51000 and 87000 plants ha–1. The number of bols （bol density） increased while bol weight decreased as plant density raised, and no signiifcant changes occured in lint percentage in 2013 but increased with plant density in 2012. The number of bols in upper nodes and distal fruiting positions, the number of seeds per bol, seed area （SA） and seed vigor index increased with decreasing plant density. Seed area was found to be greater from the base to the middle compared to the apex of a locule. Mote frequency （MF） increased as plant density increased, and ifber quality was the best at the middle of the locule regardless of plant density. As the number of ifbers per seed area is geneticaly determined, adjusting plant density to produce more seeds and greater seed area can be a potentialy promising alternative to improve lint yield in cotton. These ifndings might be of great importantance to cotton breeding and ifled management.

关键词： cotton plant density yield quality seed position

Multiparameter magnetic resonance imaging-based radiomics model for the prediction of rectal cancer metachronous liver metastasis

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 62-72页

作者： zhi-Da Long xiao yu zhi-Xiang Xing Rui Wang Department of Hepatobiliary and Pancreaticosplenic Surgery Jingzhou Hospital Affiliated to Yangtze UniversityJingzhou 434100Hubei ProvinceChina

BACKGROUND The liver,as the main target organ for hematogenous metastasis of colorectal cancer,early and accurate prediction of liver metastasis is crucial for the diagnosis and treatment of ***,this study aims to investigate the application value of a combined machine learning(ML)based model based on the multiparameter magnetic resonance imaging for prediction of rectal metachronous liver metastasis(MLM).AIM To investigate the efficacy of radiomics based on multiparametric magnetic resonance imaging images of preoperative first diagnosed rectal cancer in predicting MLM from rectal *** We retrospectively analyzed 301 patients with rectal cancer confirmed by surgical pathology at Jingzhou Central Hospital from January 2017 to December *** participants were randomly assigned to the training or validation queue in a 7:3 *** first apply generalized linear regression model(GLRM)and random forest model(RFM)algorithm to construct an MLM prediction model in the training queue,and evaluate the discriminative power of the MLM prediction model using area under curve(AUC)and decision curve analysis(DCA).Then,the robustness and generalizability of the MLM prediction model were evaluated based on the internal validation set between the validation queue *** Among the 301 patients included in the study,16.28%were ultimately diagnosed with MLM through pathological *** analysis showed that carcinoembryonic antigen,and magnetic resonance imaging radiomics were independent predictors of ***,the GLRM prediction model was developed with a comprehensive nomogram to achieve satisfactory *** prediction performance of GLRM in the training and validation queue was 0.765[95%confidence interval(CI):0.710-0.820]and 0.767(95%CI:0.712-0.822),*** with GLRM,RFM achieved superior performance with AUC of 0.919(95%CI:0.868-0.970)and 0.901(95%CI:0.850-0.952)in the training and validation queue,respect

关键词： Rectal cancer Metachronous liver metastases Magnetic resonance imaging Radiomics Machine learning

Three-dimensional Distribution of the Escape Photons of Hα Flares

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 87-95页

作者： Ming-Guo Sun Zhong-Quan Qu zhi Xu xiao-yu Zhang Cheng-Lin XU Shuai Wang Chun-Lan Jin yunnan Astronomical Observatory/National Astronomical Observatories Chinese Academy ofn Sciences Kunming 650011 Department of Astronomy Nanjing University Nanjing 210093 Graduate University of the Chinese Academy of Sciences Beijing 100049

A technique for obtaining a three-dimensional distribution of received photons in Hα flares in the solar atmosphere is presented. It is well known that during flares hydrogen atoms in the chromosphere and photosphere are excited （even ionized） by the downward heating of non-thermal particles and then emit Hα photons. We trace back these Hα photons to their original layers by use of the contribution function in the theory of spectral line formation, and so acquire their three-dimensional （3D） distribution. This technique is applied to the two-ribbon flare of 2002 January 20. The atmospheric models are obtained by fitting the ＂quasi-profiles＂ with the help of the generally used model atmospheres. Since the variety of the 3D images reflects the response of the atmospheric layers to the impact of energy transport, an analysis of the development of the flare is given through a comparison of the 3D images with the 2D temperature distribution.

关键词： line: formation - radiative transfer - sun: flares

The Synthesis of a New Type of Calixarene with Chiral Pendant

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Wuhan University Journal of Natural Sciences 2001年第3期6卷 729-732页

作者： He Yong bing, Li Jian feng, Meng Ling zhi, xiao yuan jing, yu Tian\|xiang, Wu Cheng tai College of Chemistry and Molecule Science,Wuhan University, Wuhan,430072 China Wuhan University College of Chemistry and Molecule Science Wuhan China (GRID:grid.49470.3e) (ISNI:***)

Two new chiral calixarenes were synthesized by condensing 1,3 bis chlorocarbomethyl calixarenes with (1S, 2S) 2 amino 1 (4 nitrophenyl) 1,3 propanediol, a by product from antibiotic industry , and were characterized by 1H NMR , MS FAB, and elemental analysis. The 1H NMR spectra show that those molecules assume a cone conformation in solution.

关键词： Calixarene chirality synthesis conformation

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高效的联合卷积DQPSK编码调制方法

系统工程与电子技术 2013年第10期35卷 2192-2197页

作者：吴湛击高翔崔颖肖治宇北京邮电大学信息与通信工程学院北京100876 华为技术有限公司四川成都610000

在数字通信中,90°或者180°的相位模糊是影响正交相位偏移键控(quadrature phase shift keying,QPSK)相干接收机性能的重要因素。差分正交相位偏移键控(differential QPSK,DQPSK)可以克服相位模糊,但是会导致约2.3dB的性能损失。为了消... 详细信息

在数字通信中,90°或者180°的相位模糊是影响正交相位偏移键控(quadrature phase shift keying,QPSK)相干接收机性能的重要因素。差分正交相位偏移键控(differential QPSK,DQPSK)可以克服相位模糊,但是会导致约2.3dB的性能损失。为了消除DQPSK的性能损失,提出一种低复杂度的基于迭代译码的联合卷积DQPSK编码调制方法,并且基于外信息转移图,提出了一种在DQPSK调制下优化卷积码生成多项式的算法。仿真结果表明,所提差分编码方案不仅可以克服相位模糊,而且通过迭代译码完全补偿了差分编码所导致的差分代价损失,甚至获得了3.5dB的性能增益。优化后的卷积码与IEEE 802.11n协议中给定的卷积码相比,获得了大约0.3dB的信噪比增益,和第3代合作伙伴计划(3rd generation partnership project,3GPP)长期演进(long term evolution,LTE)协议中的Turbo码相比,有大约1.1dB的性能增益。

关键词：迭代译码差分正交相位偏移键控卷积码外信息转移图 Turbo码最大后验概率算法

OB glue paste technique for establishing nude mouse human gastric cancer orthotopic transplantation models

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World Journal of Gastroenterology 2008年第30期14卷 4800-4804页

作者： Jun Shi Pin-Kang Wei Shen Zhang zhi-Feng Qin Jun Li Da-zhi Sun Yan xiao zhi-Hong yu Hui-Ming Lin Guo-Jing Zheng xiao-Mei Su Ya-Lin Chen Yan-Fang Liu Ling Xu Department of Traditional Chinese Medicine Shanghai Changzheng Hospital Shanghai 200003 China

AIM： To establish nude mouse human gastric cancer orthotopic transplantation models using OB glue paste technique. METHODS： Using OB glue paste technique, orthtopic transplantation models were established by implanting SGC-7901 and NKN-45 human gastric cancer cell strains into the gastric wall of nude mice. Biological features, growth of the implanted tumors, the success rate of transplantation and the rate of auto-metastasis of the two models were observed. RESULTS： The success rates of orthotopic transplanration of the two models were 94.20% and 96%. The rates of hepatic metastasis, pulmonary metastasis, peritoneal metastasis, lymphocytic metastasis and splenic metastasis were 42.13% and 94.20%, 48.43% and 57.97%, 30.83% and 36.96%, 67.30% and 84.06%, and 59.75% and 10.53%, respectively. The occurrence of ascites was 47.80% and 36.96%. CONCLUSION： OB glue paste technique is easy to follow. The biological behaviors of the nude mouse human gastric cancer orthotopic transplantation models established with this technique are similar to the natural processes of growth and metastasis of human gastric cancer, and, therefore, can be used as an ideal model for experimental research of proliferative metastasis of tumors.

关键词： Gastric tumor Tumor transplantation Disease models Animal Nude mice

机械振动对挤压铸造A356铝合金组织与性能的影响

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华南理工大学学报（自然科学版） 2017年第2期45卷 46-51页

作者：周照耀曹小兵秦杰肖志瑜华南理工大学机械与汽车工程学院广东广州510640

研究了挤压铸造过程中机械振动对A356铝合金材料显微组织与力学性能的影响规律,并对机械振动击碎枝晶的作用机理进行了阐述。结果表明:施加机械振动能够有效地消除材料缩松缩孔及断面裂纹,减少甚至消除挤压铸造铝合金铸锭的微观孔洞,细... 详细信息

研究了挤压铸造过程中机械振动对A356铝合金材料显微组织与力学性能的影响规律,并对机械振动击碎枝晶的作用机理进行了阐述。结果表明:施加机械振动能够有效地消除材料缩松缩孔及断面裂纹,减少甚至消除挤压铸造铝合金铸锭的微观孔洞,细化晶粒组织,使得组织更加均匀;挤压铸造凝固初期,机械振动能够在很大程度上破碎二次枝晶臂,增加材料的形核率;试验值与理论值的对比分析表明,Kirkwood模型具有更高的精度;机械振动能够提高材料的力学性能,相较于重力铸造与无振动挤压铸造而言,所得铸件的抗拉强度与延伸率均有一定提高.

关键词：机械振动挤压铸造铝合金显微组织力学性能