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Cytocompatibility of regenerated silk fibroin film:a medical biomaterial applicable to wound healing

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第1期11卷 10-16页

作者： Tie-lian LIU jing-cheng MIAO Wei-hua sheng Yu-feng XIE Quan HUANG Yun-bo SHAN ji-cheng YANG Cell and Molecular Biology Institute College of Medicine Soochow University Suzhou 215123 China Laboratory Department of the Third Affiliated Hospital of Southern Medical University Guangzhou 510630 China Department of Renal Medicine Nantong Municipal No. 1 People's Hospital Nantong 226001 China

Objective： To explore the feasibility of using regenerated silk fibroin membrane to construct artificial skin substitutes for wound healing, it is necessary to evaluate its cytocompatibility. Methods： The effects of regenerated silk fibroin film on cytotoxicity, adhesion, cell cycle, and apoptosis of L929 cells, growth and vascular endothelial growth factor （VEGF） expression of ECV304 cells, and VEGF, angiopoietin-1 （Ang-1）, platelet-derived growth factor （PDGF） and fibroblast growth factor 2 （FGF2） expression of WI-38 cells were assessed by 3-（4,5）-dimethylthiahiazo （-z-yl）-3,5-di-phenytetrazoliumromide （MTT） assay, viable cell counting, flow cytometry （FCM）, and enzyme-linked immunosorbant assay （ELISA）. Results： We showed that the regenerated silk fibroin film was not cytotoxic to L929 cells and had no adverse influence on their adhesion, cell cycle or apoptosis; it had no adverse influence on the growth and VEGF secretion of ECV304 cells and no effect on the secretion of VEGF, Ang-1, PDGF and FGF2 by WI-38 cells. Conclusion： The regenerated silk fibroin film should be an excellent biomaterial with good cytocompatibility, providing a framework for reparation after trauma in clinical applications.

关键词： Regenerated silk fibroin film Cytocompatibility Cytotoxicity

Comparative study of intracavernous pressure and cavernous pathology after bilateral caver nous n erve crushing and resection in rats

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Asian Journal of Andrology 2020年第6期22卷 629-635页

作者： Meng Li Yi-Ming Yuan Bi-cheng Yang sheng-ji Gu Hui-Xi Li Zhong-cheng Xin Dong Fang Rui-Li Guan Molecular Biology Laboratory of Andrology Center Peking University First HospitalPeking UniversityBeijing 100034China

This study aimed to compare the effects of bilateral cavernous nerve crushing(BCNC)and bilateral cavernous nerve resection(BCNR)on intracavernous pressure(ICP)and cavernous pathology in rats and to explore the optimal treatment time for the BCNC and BCNR ***-two male rats aged 12 weeks were randomly divided into three equal groups:Sham(both cavernous nerves exposed only),BCNC(BCN crushed for 2 min),and BCNR(5 mm of BCN resected).Erectile function was then measured at 1 week,3 weeks,and 5 weeks after nerve injury,and penile tissues were harvested for histological and molecular analyses by immunohistochemistry,immuno fluoresce nee,Western blot,and cytokine *** found that erectile function parameters including the maximum,area,and slope of ICP/mean arterial pressure(MAP)significantly decreased after BCNR and BCNC at 1 week and 3 *** 5 weeks,no significant differences were observed in ICP/MAP between the BCNC and Sham groups,whereas the ICP/MAP of the BCNR group remained significantly lower than that of the Sham *** BCNC and BCNR,the amount of neuronal-nitric oxide synthase-positive fibers,smooth muscle cells,and endothelial cells decreased,whereas the amount of collage n III con tent *** pathological cha nges recovered over time,especially in the BCNC *** fin dings demonstrate that BCNC leads to acute and reversible erectile dysfunction,thus treatme nt time should be restricted to the first 3 weeks *** contrast,the self-healing ability of the BCNR model is poor,making it more suitable for long-term treatment research.

关键词： caver nous nerve crushing cavernous nerve resection erectile dysfunction in tracavernous pressure

Stereoselective Addition of N-Alkylhydroxylamines to α,β-Unsaturated Nitro Compounds

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Chinese Chemical Letters 2006年第7期17卷 859-862页

作者： Ai Jun LI ji cheng CHU Hong sheng GUO Xue Qin ZHOU Dong Zhi LIU School of Chemical Engineering and Technology Tianjin University Tianjin 300072 Medical College Chinese People＇s Armed Police Force Tianjin 300071

N-Alkylhydroxylamines have been shown to undergo a stereospecific cis addition to 1-phenyl-2 -nitropropene compounds, whereas the corresponding O-alkylhydroxylamines give no diastereoselectivity. The concerted additio... 详细信息

关键词： N-Alkylhydroxylamines O-alkylhydroxylamines concerted addition mechanism α,β-unsaturated nitro compounds stereoselectivity.

High-throughput experimental tools for the materials genome initiative

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Chinese Science Bulletin 2014年第15期59卷 1652-1661页

作者： ji-cheng Zhao Department of Materials Science and Engineering The Ohio State University State Key Laboratory of Powder Metallurgy Central South University

The materials innovation infrastructure in the materials genome initiative(MGI)consists of three major components:computational tools,experimental tools,and digital *** article will review experimental tools for high-throughput,high spatial resolution measurements of several materials properties such as elastic modulus,thermal conductivity,specific heat capacity,and thermal *** of these tools on compositionvarying samples such as diffusion multiples can be used to quickly and efficiently obtain composition–phase–structure–property relationships for materials property database *** can also be used in conjunction with theoretical modeling to find and explain unusual effects to improve the predictability of *** micron scale resolution experimental tools are in *** high-throughput tools will be an essential part of MGI.

关键词：计算工具材料性能基因组计划高通量实验高空间分辨率属性数据库组成部分

Incipient sediment motion based on turbulent fluctuations

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International Journal of Sediment Research 2020年第2期35卷 125-133页

作者： Wan Hanna Melini Wan Mohtar ji Wang Lee Najwa Izzaty Mohammad Azha Nian-sheng cheng Department of Civil & Structural Engineering Faculty of Engineering and Built EnvironmentUniversiti Kebangsaan Malaysia School of Civil and Environmental Engineering College of EngineeringNanyang Technical University

The current study modifies the representation of the Shields parameter using turbulent strength,*** root-mean-square(rms) fluid *** were done under a steady,uniform flow using eight sediment sizes with particle Reynolds numbers(Rep) ranging between 1.0(fine sediment) and 183.4(coarse sediment).Utilising the peak rms horizontal(u) values,the critical Shields parameter,θ,was calculated and a trend similar to the well-established Shields curve was *** analysis was extended to the Shields curve obtained based on the critical shear velocity,Reynolds shear stress,and data extracted fro m the oscillating grid-turbulence *** show that turbulent fluctuations are crucial for the incipient sediment motion and are essentially better predictors than the commonly used critical shear velocity.A quadrant analysis to identify the role of turbulent bursting events in incipient sediment motion also was done where sweeps and ejections are dominant for finer and coarser sediment sizes,respectively.

关键词： Incipient sediment motion Root-mean-square fluid velocity Grid-turbulence Quadrant analysis Turbulent fluctuations

Infinitesimal dividing modeling method for dual suppliers inventory model with random lead times

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Journal of Systems Engineering and Electronics 2009年第3期20卷 527-536页

作者： ji Pengcheng Song Shiji Wu cheng Dept. of Automation Tsinghua Univ. Beijing 100084 P. R. China

As one of the basic inventory cost models, the （Q, τ）inventory cost model of dual suppliers with random procurement lead time is mostly formulated by using the concepts of ＂effective lead time＂ and ＂lead time demand＂, which may lead to an imprecise inventory cost. Through the real-time statistic of the inventory quantities, this paper considers the precise （Q, τ） inventory cost model of dual supplier procurement by using an infinitesimal dividing method. The traditional modeling method of the inventory cost for dual supplier procurement includes complex procedures. To reduce the complexity effectively, the presented method investigates the statistics properties in real-time of the inventory quantities with the application of the infinitesimal dividing method. It is proved that the optimal holding and shortage costs of dual supplier procurement are less than those of single supplier procurement respectively. With the assumption that both suppliers have the same distribution of lead times, the convexity of the cost function per unit time is proved. So the optimal solution can be easily obtained by applying the classical convex optimization methods. The numerical examples are given to verify the main conclusions.

关键词： inventory precise model random lead times dual supplier infinitesimal dividing method optimiza- tion.

A comparison between magnetic shear and flare shear in a well-observed M-class flare

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Chinese Journal of Astronomy and Astrophysics 2009年第3期9卷 323-332页

作者： Tuan-Hui Zhou Hai-sheng ji Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China Graduate School of the Chinese Academy of Sciences Beijing 100049 China

We give an extensive multi-wavelength analysis of an eruptive M1.0/1N class solar flare, which occurred in the active region NOAA 10044 on 2002 July 26. Our emphasis is on the relationship between magnetic shear and flare shear. Flare shear is defined as the angle formed between the line connecting the centroids of the two ribbons of the flare and the line perpendicular to the magnetic neutral line. The magnetic shear is computed from vector magnetograms observed at Big Bear Solar Observatory （BBSO）, while the flare shear is computed from Transition Region and Coronal Explorer （TRACE） 1700A images. By a detailed comparison, we find that; 1） The magnetic shear and the flare shear of this event are basically consistent, as judged from the directions of the transverse magnetic field and the line connecting the two ribbons＇ centroids. 2） During the period of the enhancement of magnetic shear, flare shear had a fast increase followed by a fluctuated decrease. 3） When the magnetic shear stopped its enhancement, the fluctuated decreasing behavior of the flare shear became very smooth. 4） Hard X-ray （HXR） spikes are well correlated with the unshearing peaks on the time profile of the rate of change of the flare shear. We give a discussion of the above phenomena.

关键词： Sun flare - Sun magnetic field - Sun sunspot

Background knowledge based privacy metric model for online social networks

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 75-82页

作者： cheng cheng ZHANG Chun-hong ji Yang School of Information and Communication Engineering Beijing University of Posts and Telecommunications

The data of online social network （OSN） is collected currently by the third party for various purposes. One of the problems in such practices is how to measure the privacy breach to assure users. The recent work on OSN privacy is mainly focus on privacy-preserving data publishing. However, the work on privacy metric is not systematic but mainly focus on the traditional datasets. Compared with the traditional datasets, the attribute types in OSN are more diverse and the tuple is relevant to each other. The retweet and comment make the graph character of OSN notably. Furthermore, the open application programming interfaces （APIs） and lower register barrier make OSN open environment, in which the background knowledge is more easily achieved by adversaries. This paper analyzes the background knowledge in OSN and discusses its characteristics in detail. Then a privacy metric model faces OSN background knowledge based on kernel regression is proposed. In particular, this model takes the joint attributes and link knowledge into consideration. The effect of different data distributions is discussed. The real world data set from *** has been adopted. It is demonstrated that the privacy metric algorithm in this article is effective in OSN privacy evaluation. The prediction error is 30% lower than that of the work mentioned above

关键词： privacy metric social network background knowledge kernel regression

Vascular disrupting agent-induced amplification of tumor targeting and prodrug activation boosts anti-tumor efficacy

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Science China Chemistry 2022年第10期65卷 1994-2004页

作者： sheng Hong Qian-Xiao Huang Ping ji Xuan Pang Yunxia Sun Si-Xue cheng Xian-Zheng Zhang Xuesi Chen Key Laboratory of Biomedical Polymers of Ministry of Education Department of ChemistryWuhan UniversityWuhan 430072China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Vadimezan,one of the typical vascular disrupting agents(VDAs) currently in clinical trials,has been extensively implemented for cancer research,whereas its clinical efficacy is adversely affected by the inevitable side *** by Vadimezaninduced intratumoral coagulation activation and hypoxia aggravation,we report a strategy by utilizing these biological effects to achieve targeted delivery and activation of hypoxia-activated prodrug(HAP) thus to maximize the therapeutic effect of *** encapsulating HAP tirapazamine into poly(lactic-co-glycolic acid)(PLGA) nanocarriers along with the modification of clot-binding peptide,the obtained nanoplatform could target tumors under the coagulation activation effect of ***,the aggravated hypoxia tumor microenvironment induced by Vadimezan can also boost hypoxia-activated *** the murine tumor model,this strategy showed 80.0% suppression of tumor growth,indicating its great potential in tumor *** study offers an ingenious tactic for the combination of vascular disrupting therapy and hypoxia-activated chemotherapy,which may open up a window of the VDAs-based combination therapy.

关键词： tumor therapy prodrug vascular disrupting agent tirapazamine hypoxia