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稻盛和夫经营伦理中“单纯”理念探微 被引量:6
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作者 刘庆红 《伦理学研究》 CSSCI 北大核心 2018年第3期112-117,共6页
稻盛和夫是日本著名的企业家,在企业的经营与管理中,建立了独树一帜的经营伦理思想体系,用于规划企业的发展战略及指导企业具体实践,不仅创下了经营奇迹,而且在多变的市场风云中,企业一直处于创新与稳定发展的态势。稻盛和夫经营伦理思... 稻盛和夫是日本著名的企业家,在企业的经营与管理中,建立了独树一帜的经营伦理思想体系,用于规划企业的发展战略及指导企业具体实践,不仅创下了经营奇迹,而且在多变的市场风云中,企业一直处于创新与稳定发展的态势。稻盛和夫经营伦理思想的核心理念便是"单纯",但在其"单纯"的经营伦理思想里却涵盖了博大精深的东方文化精髓。笔者通过对其"单纯"理念的内涵与外延进行分析,一方面探索稻盛和夫独特的经营之道;另一方面探索东方文化的当代现实性应用。 展开更多
关键词 稻盛和夫 经营伦理 “单纯”理念 中国传统文化 现实性应用
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“单纯”的艺术魅力与追求
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作者 杨晓见 《成都师专学报》 2002年第3期51-52,共2页
艺术创作应该选择尽可能单纯的语言来表述。艺术总是在一定的约束和抑制之下挣扎着实现张扬,艺术家应该学会适于、始终安于、直至乐于在限制中施展其才华,在有限中追寻无限。
关键词 艺术创作 “单纯” 语言 艺术形式
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Study on Joint Method of 3D Acoustic Emission Source Localization Simplex and Grid Search Scanning
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作者 Liu Wei-jian Wang Hao-nan +4 位作者 Xiao Yang Hou Meng-jie Dong Sen-sen Zhang Zhi-zeng Lu Gao-ming 《Applied Geophysics》 SCIE CSCD 2024年第3期456-467,617,共13页
Acoustic emission(AE)source localization is a fundamental element of rock fracture damage imaging.To improve the efficiency and accuracy of AE source localization,this paper proposes a joint method comprising a three-... Acoustic emission(AE)source localization is a fundamental element of rock fracture damage imaging.To improve the efficiency and accuracy of AE source localization,this paper proposes a joint method comprising a three-dimensional(3D)AE source localization simplex method and grid search scanning.Using the concept of the geometry of simplexes,tetrahedral iterations were first conducted to narrow down the suspected source region.This is followed by a process of meshing the region and node searching to scan for optimal solutions,until the source location is determined.The resulting algorithm was tested using the artificial excitation source localization and uniaxial compression tests,after which the localization results were compared with the simplex and exhaustive methods.The results revealed that the localization obtained using the proposed method is more stable and can be effectively avoided compared with the simplex localization method.Furthermore,compared with the global scanning method,the proposed method is more efficient,with an average time of 10%–20%of the global scanning localization algorithm.Thus,the proposed algorithm is of great significance for laboratory research focused on locating rupture damages sustained by large-sized rock masses or test blocks. 展开更多
关键词 acoustic emission simplex form grid search scan locating the epicenter
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《再别康桥》是一首单纯的惜别诗吗?——“爱、自由与美”的“单纯信仰”幻灭后的诗意祭奠
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作者 古大勇 谭进荣 《社会科学论坛(学术研究卷)》 2008年第6期131-133,共3页
徐志摩1920~1922年在康桥留学时期形成了以"爱""自由"与"美"为中心的"单纯信仰"。1928年重游故地写作《再别康桥》时,"单纯信仰"已经无情幻灭。因此,《再别康桥》不仅仅是一首单纯... 徐志摩1920~1922年在康桥留学时期形成了以"爱""自由"与"美"为中心的"单纯信仰"。1928年重游故地写作《再别康桥》时,"单纯信仰"已经无情幻灭。因此,《再别康桥》不仅仅是一首单纯的惜别诗,它是诗人"单纯信仰"幻灭后的一份感伤的诗意祭奠。 展开更多
关键词 《再别康桥》 “单纯信仰” 幻灭 祭奠
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浅谈针对农村音乐多学科综合运用课堂教学法——“单纯音符”课堂教学法
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作者 徐颖 《中国校外教育(中旬)》 2012年第2期35-35,167,共2页
长期以来,由于受各种因素的影响,农村地区专业音乐教师缺乏,音乐教学不太被学校重视;音乐教学设施简陋,许多学校连起码的教学乐器都不具备;对音乐的学习缺乏家长的支持,学生自身又不重视,从而最终导致农村学生现有的音乐经验缺乏,对所... 长期以来,由于受各种因素的影响,农村地区专业音乐教师缺乏,音乐教学不太被学校重视;音乐教学设施简陋,许多学校连起码的教学乐器都不具备;对音乐的学习缺乏家长的支持,学生自身又不重视,从而最终导致农村学生现有的音乐经验缺乏,对所授音乐知识听不懂、没兴趣,农村学生的音乐素质普遍偏低的严重后果。就这些问题,我在教学中,立足学生、学校的实际情况,依托教材及本人所掌握的音乐知识,采用音乐与其他学科综合运用的教学方法,特别是在"单纯音符"的理论学习中,此种方法发挥了很好的功效,改善了学生对音乐知识的理解能力和学习兴趣。 展开更多
关键词 农村 音乐教学 “单纯音符” 教学法
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Prediction of compressive strength of cement mortars with fly ash and activated coal gangue 被引量:5
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作者 周双喜 陈益民 张文生 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期549-552,共4页
The pozzolanic activity of coal gangue, which is calcining at 500 to 1 000 ℃, differs distinctly. The simplex-centroid design with upper and lower bounds of component proportion is adopted to study the compressive st... The pozzolanic activity of coal gangue, which is calcining at 500 to 1 000 ℃, differs distinctly. The simplex-centroid design with upper and lower bounds of component proportion is adopted to study the compressive strength of mortars made with ternary blends of cement, activated coal gangue and fly ash. Based on the results of a minimum of seven design points, three special cubic polynomial models are used to establish the strength predicating equations at different ages for mortars. Five experimental checkpoints were also designed to verify the precision of the equations. The most frequent errors of the predicted values are within 3%. A simple and practical way is provided for determining the optimal proportion of two admixtures when they are used in concrete. 展开更多
关键词 thermal activated coal gangue simplex-centroid design predicating equation compressive strength
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CATGUT EMBEDDING FOR TREATMENT OF SIMPLE OBESITY COMPLICATED WITH ABNORMAL BLOOD FAT 被引量:4
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作者 卢文 朱礼刚 +2 位作者 苏清伦 房忠女 周源 《World Journal of Acupuncture-Moxibustion》 2008年第3期1-8,共8页
Objective To compare the therapeutic effect of catgut embedding combined with diet plus exercise with that of diet plus exercise in treating simple obesity complicated with abnormal blood fat. Methods A prescription o... Objective To compare the therapeutic effect of catgut embedding combined with diet plus exercise with that of diet plus exercise in treating simple obesity complicated with abnormal blood fat. Methods A prescription of diet plus exercise was given to the patients in a control group, and catgut embedding was added to the prescription in a treatment group. It was given once every 15 days for the 1st three treatments, and once every month for the 2^nd three treatments. Six treatments constituted a therapeutic course. Body weight and blood fat were measured before and half a year since treatment. Results After treatment, BMI, TO, TG and LDL were very significantly improved in the treatment group (P〈0.01), and BMI and TG were very significantly (P〈0.01) and TO and LDL were significantly (P〈0.05) improved in the control group. HDL was not obviously improved in both groups (P〉0.05). The improvement of TO, TG and LDL in the treatment group was significantly more than that in the control group (P〈0.01), but no difference in improvement of BMI and HDL was found between the two groups (P〉0.05). Conclusion The therapy of diet plus exercise was effective in body weight reduction and lowering blood fat in patients with simple obesity complicated with abnormal blood fat, and catgut embedding used in combination was even better in lowering blood fat. 展开更多
关键词 Catgut Embedding Simple Obesity Abnormal Blood Fat
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A non-monotone Phase-1 method in linear programming 被引量:4
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作者 潘平奇 李炜 《Journal of Southeast University(English Edition)》 EI CAS 2003年第3期293-296,共4页
To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventiona... To gain superior computational efficiency, it might be necessary to change the underlying philosophy of the simplex method. In this paper, we propose a Phase-1 method along this line. We relax not only the conventional condition that some function value increases monotonically, but also the condition that all feasible variables remain feasible after basis change in Phase-1. That is, taking a purely combinatorial approach to achieving feasibility. This enables us to get rid of ratio test in pivoting, reducing computational cost per iteration to a large extent. Numerical results on a group of problems are encouraging. 展开更多
关键词 linear programming Phase-1 ratio-test-free pivoting rule
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THREE-DIMENSIONAL TRAJECTORY OPTIMIZATION WITH DIRECT METHOD 被引量:1
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作者 沈春林 刘国刚 +1 位作者 吴文海 李丽荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期118-122,共5页
The principle of direct method used in optimal control problem is introduced. Details of applying this method to flight trajectory generation are presented including calculation of velocity and controls histories. And... The principle of direct method used in optimal control problem is introduced. Details of applying this method to flight trajectory generation are presented including calculation of velocity and controls histories. And capabilities of flight and propulsion systems are considered also. Combined with digital terrain map technique, the direct method is applied to the three dimensional trajectory optimization for low altitude penetration, and simplex algorithm is used to solve the parameters in optimization. For the small number of parameters, the trajectory can be optimized in real time on board. 展开更多
关键词 direct optimization method trajectory optimization low altitude penetration simplex algorithm
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Construction of retroviral vector carrying HSV tk gene under control of human AFP enhancer core sequence and human pgk promotor * 被引量:1
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作者 高军 曹广文 +5 位作者 戚中田 仇小芳 吴宗娣 杜平 杨文国 崔龙 《World Journal of Gastroenterology》 SCIE CAS CSCD 1997年第1期14+12-13,12-13,共3页
AIM Tenstruct retroviral vector bringing HSV tk gene under control by human AFP enhancer core sequence and human pgk promotor.
关键词 Liver neoplasms\ \ Simplexvirus\ \ Retroviridae\ \ alpha fetoproteins Enhancer elements (genetics)\ \ Gene therapy
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Effect of HSV-2 Infected Monocytes on the Production of TNF-a and IL-6
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作者 敖俊红 杨蓉娅 +2 位作者 王文岭 周礼义 陈兴平 《Chinese Journal of Sexually Transmitted Infections》 2003年第2期47-48,70,共3页
Objective: In order to detect the role of monocytes inHSV-2 infection, we studied the effect of herpes sim-plex Virus-2 infection on the production of tumor ne-crosis factor (TNF-σ), interleukin-6 (IL-6) secretedby m... Objective: In order to detect the role of monocytes inHSV-2 infection, we studied the effect of herpes sim-plex Virus-2 infection on the production of tumor ne-crosis factor (TNF-σ), interleukin-6 (IL-6) secretedby monocytes. Methods: Monocytes were infected by HSV-2 (333Strain). Culture supernatants were collected at 1, 3,5, 7 days post-infection. The levels of TNF-α, IL-6were measured by enzyme-linked immunosorbent as-say (ELISA). Results: The levels of TNF-α secretion by mono-cytes significantly decreased on first day post-infection. The levels of IL-6 significantly decreasedon first and third days post-infection, and then gradu-ally increased to the control on seventh day post-infection. Conclusions: TNF-α and IL-6 production by mono-cytes was inhibited during HSV-2 infection. The pro-duction of cytokines may play an important role inherpes simplex viurs-2 pathogenicity and immunity. 展开更多
关键词 HSV-2 MONOCYTES CYTOKINES
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Effect of Herpes Simplex Virus-2 Infection in Vitro on the Expression of HLA Class II Antigen of Monocytes
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作者 敖俊红 周礼义 +2 位作者 陈兴平 杨蓉娅 宋克敏 《Chinese Journal of Sexually Transmitted Infections》 2004年第1期25-27,63,共4页
Objectives: In order to investigate the role of mono-cytes and human leukocyte antigen (HLA) class II an-tigen in herpes simplex virus-2 (HSV-2) infection, westudied the effect of HSV-2 infection in vitro on theexpres... Objectives: In order to investigate the role of mono-cytes and human leukocyte antigen (HLA) class II an-tigen in herpes simplex virus-2 (HSV-2) infection, westudied the effect of HSV-2 infection in vitro on theexpression of HLA class II antigen on monocytes.Methods: Monocytes were infected with HSV-2(Strain 333). Culture cells were collected 1, 3, 5 and 7days after infection. The levels of expression of HLAclass II antigen were measured by using alkaline phos-phatase antialkaline phosphatase method (APAAP).Results: The levels of the expression of HLA class IIantigen on monocytes significantly decreased on thefirst day of post-infection, and then gradually returnedto levels found in the controls by the 7th day post-infection.Conclusion: HLA class II antigen expression onmonocytes was inhibited with HSV-2 infection, whichmight be one means of virus escape at an early phase.The expression of HLA class II antigen may play animportant role in herpes simplex viurs-2 pathogenic-ity and immunity. 展开更多
关键词 HSV-2 MONOCYTE HLA class II antigen
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'The Theory of Field-Effect Transistors XII.The Bipolar Drift and Diffusion Currents(1-2-MOS-Gates on Thin-Thick Pure-Impure Base)
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作者 揭斌斌 薩支唐 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1227-1241,共15页
The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-ba... The previous report (XI) gave the electrochemical-potential theory of the Bipolar Field-Effect Transistors. This report (XII) gives the drift-diffusion theory. Both treat 1-gate and 2-gate, pure-base and impure-base, and thin and thick base. Both utilize the surface and bulk potentials as the parametric variables to couple the voltage and current equations. In the present drift-diffusion theory, the very many current terms are identified by their mobility multiplier for the components of drift current,and the diffusivity multiplier for the components of the diffusion current. Complete analytical driftdiffusion equations are presented to give the DC current-voltage characteristics of four common MOS transistor structures. The drift current consists of four terms: 1-D (One-Dimensional) bulk charge drift term, 1-D carrier space-charge drift term,l-D Ex^2 (transverse electric field) drift term,2-D drift term. The diffusion current consists of three terms: 1-D bulk charge diffusion term,l-D carrier space-charge diffusion term,and 2-D diffusion term. The 1-D Ex^2 drift term was missed by all the existing transistor theories, and contributes significantly, as much as 25 % of the total current when the base layer is nearly pure. The 2-D terms come from longitudinal gradient of the longitudinal electric field,which scales as the square of the Debye to Channel length ratio, at 25nm channel length with nearly pure base, (LD/L)^2 = 10^6 but with impurity concentration of 10^18cm^-3 , (LD/L)^2 = 10^-2 . 展开更多
关键词 bipolar field-effect transistor theory surface potential drift and diffusion theory single-gate impure-base double-gate impure-base
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Soluble forms of extracellular cytokeratin 18 may differentiate simple steatosis from nonalcoholic steatohepatitis 被引量:19
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作者 Yusuf Yilmaz Enver Dolar +8 位作者 Engin Ulukaya Semra Akgoz Murat Keskin Murat Kiyici Sibel Aker Arzu Yilmaztepe Selim Gurel Macit Gulten Selim Giray Nak 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第6期837-844,共8页
AIM: To investigate whether serum levels of two soluble forms of extracellular cytokeratin 18 (M30-antigen and M65-antigen) may differentiate nonalcoholic steatohepatitis (NASH) from simple steatosis in patients with ... AIM: To investigate whether serum levels of two soluble forms of extracellular cytokeratin 18 (M30-antigen and M65-antigen) may differentiate nonalcoholic steatohepatitis (NASH) from simple steatosis in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: A total of 83 patients with suspected NAFLD and 49 healthy volunteers were investigated. Patients with suspected NAFLD were classified according to their liver histology into four groups: definitive NASH (n = 45), borderline NASH (n = 24), simple fatty liver (n = 9), and normal tissue (n = 5). Serum levels of caspase-3 generated cytokeratin-18 fragments (M30-antigen) and total cytokeratin-18 (M65-antigen) were determined by ELISA. RESULTS: Levels of M30-antigen and M65-antigen were significantly higher in patients with definitive NASH compared to the other groups. An abnormal value (> 121.60 IU/L) of M30-antigen yielded a 60.0% sensitivity and a 97.4% specificity for the diagnosis of NASH. Sensitivity and specificity of an abnormal M65-antigen level (> 243.82 IU/L) for the diagnosis of NASH were 68.9% and 81.6%, respectively. Among patients with NAFLD, M30-antigen and M65-antigen levels distinguished between advanced fibrosis and early-stage fibrosis with a sensitivity of 64.7% and 70.6%, and a specificity of 77.3% and 71.2%, respectively. CONCLUSION: Serum levels of M30-antigen and M65-antigen may be of clinical usefulness to identify patients with NASH. Further studies are mandatory to better assess the role of these apoptonecrotic biomarkers in NAFLD pathophysiology. 展开更多
关键词 STEATOSIS STEATOHEPATITIS Cytokeratin 18 M30-antigen M65-antigen
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The Herpes Simplex Virus Type 1 Multiple Function Protein ICP27 被引量:6
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作者 Lei ZHAO Wen-bo ZHU Qiong DING Gui-qing PENG Chun-fu ZHENG 《Virologica Sinica》 SCIE CAS CSCD 2008年第6期399-405,共7页
The herpes simplex virus type 1 (HSV-1) infected-cell protein 27 (ICP27) is an essential, highly conserved protein involved in various steps of HSV-1 gene regulation as well as in the shut-off of host gene express... The herpes simplex virus type 1 (HSV-1) infected-cell protein 27 (ICP27) is an essential, highly conserved protein involved in various steps of HSV-1 gene regulation as well as in the shut-off of host gene expression during infection. It functions primarily at the post-transcriptional level in inhibiting precursor mRNA splicing and in promoting nuclear export of viral transcripts. Recently, many novel functions performed by the HSV- 1 ICP27 protein were shown, including leptomycin B resistance, inhibition of the type I interferon signaling, regulation of the viral mRNA translation and determining the composition of HSV-1 virions 展开更多
关键词 Herpes simplex virus type 1 (HSV-1) Infected-cell protein 27 (ICP27) Nuclear export LeptomycinB (LMB) Interferon (IFN)
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Pure red cell aplasia due to parvovirus B19 infection after liver transplantation:A case report and review of the literature 被引量:8
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作者 Ting-Bo Liang Dong-Lin Li Jun Yu Xue-Li Bai Liang Liang Shi-Guo Xu Wei-Lin Wang Yan Shen Min Zhang Shu-Sen Zheng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第13期2007-2010,共4页
Pure red cell aplasia (PRCA) due to parvovirus B19 (PVB19) infectiori after solid organ transplantation has been rarely reported and most of the cases were renal transplant recipients, Few have been described afte... Pure red cell aplasia (PRCA) due to parvovirus B19 (PVB19) infectiori after solid organ transplantation has been rarely reported and most of the cases were renal transplant recipients, Few have been described after liver transplantation. Moreover, little information on the management of this easily recurring disease is available at present. We describe the first case of a Chinese liver transplant recipient with PVB19-induced PRCA during immunosuppressive therapy. The patient suffered from progressive anemia with the lowest hemoglobin level of 21 g/L. Bone marrow biopsy showed selectively inhibited erythropoiesis with giant pronormoblasts. Detection of PVB19-DNA in serum with quantitative polymerase chain reaction (PCR) revealed a high level of viral load. After 2 courses of intravenous immunoglobulin (IVIG) therapy, bone marrow erythropoiesis recovered with his hemoglobin level increased to 123 g/L. He had a lowlevel PVB19 load for a 5-too follow-up period without recurrence of PRCA, and finally the virus was cleared. Our case indicates that clearance of PVB19 by IVIG in transplant recipients might be delayed after recovery of anemia. 展开更多
关键词 Pure red cell aplasia Parvovirus B19 Intravenous immunoglobulin RECURRENCE LIVERTRANSPLANTATION
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A novel particle swarm optimizer without velocity:Simplex-PSO 被引量:5
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作者 肖宏峰 谭冠政 《Journal of Central South University》 SCIE EI CAS 2010年第2期349-356,共8页
A simplex particle swarm optimization(simplex-PSO) derived from the Nelder-Mead simplex method was proposed to optimize the high dimensionality functions.In simplex-PSO,the velocity term was abandoned and its referenc... A simplex particle swarm optimization(simplex-PSO) derived from the Nelder-Mead simplex method was proposed to optimize the high dimensionality functions.In simplex-PSO,the velocity term was abandoned and its reference objectives were the best particle and the centroid of all particles except the best particle.The convergence theorems of linear time-varying discrete system proved that simplex-PSO is of consistent asymptotic convergence.In order to reduce the probability of trapping into a local optimal value,an extremum mutation was introduced into simplex-PSO and simplex-PSO-t(simplex-PSO with turbulence) was devised.Several experiments were carried out to verify the validity of simplex-PSO and simplex-PSO-t,and the experimental results confirmed the conclusions:(1) simplex-PSO-t can optimize high-dimension functions with 200-dimensionality;(2) compared PSO with chaos PSO(CPSO),the best optimum index increases by a factor of 1×102-1×104. 展开更多
关键词 Nelder-Mead simplex method particle swarm optimizer high-dimension function optimization convergence analysis
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In vitro Anti-viral Activity of the Total Alkaloids from Tripterygium hypoglaucum against Herpes Simplex Virus Type 1 被引量:7
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作者 Zhe REN Chuan-hai ZHANG +7 位作者 Lian-jun WANG Yun-xia CUI Ren-bin QI Chong-ren YANG Ying-jun ZHANG Xiao-yi WEI Da-xiang LU Yi-fei WANG 《Virologica Sinica》 SCIE CAS CSCD 2010年第2期107-114,共8页
Herpes simplex virus type 1 (HSV-1) is a commonly occurring human pathogen worldwide. There is an urgent need to discover and develop new alternative agents for the management of HSV-1 infection. Tripterygium hypogl... Herpes simplex virus type 1 (HSV-1) is a commonly occurring human pathogen worldwide. There is an urgent need to discover and develop new alternative agents for the management of HSV-1 infection. Tripterygium hypoglaucum (level) Hutch (Celastraceae) is a traditional Chinese medicine plant with many pharmacological activities such as anti-inflammation, anti-tumor and antifertility. The usual medicinal part is the roots which contain about a 1% yield of alkaloids. A crude total alkaloids extract was prepared from the roots of T. hypoglaucum amd its antiviral activity against HSV-1 in Vero cells was evaluated by cytopathic effect (CPE) assay, plaque reduction assay and by RT-PCR analysis. The alkaloids extract presented low cytotoxicity (CC50 = 46.6μg/mL) and potent CPE inhibition activity, the 50% inhibitory concentration (ICs0) was 6.5 μg/mL, noticeably lower than that of Acyclovir (15.4μg /mL). Plaque formation was significantly reduced by the alkaloids extract at concentrations of 6.25 μg/mL to 12.5 μg/mL, the plaque reduction ratio reached 55% to 75% which was 35% higher than that of Acyclovir at the same concentration. RT-PCR analysis showed that, the transcription of two important delayed early genes UL30 and UL39, and a late gene US6 of HSV-1 genome all were suppressed by the alkaloids extract, the expression inhibiting efficacy compared to the control was 74.6% (UL30), 70.9% (UL39) and 62.6% (US6) respectively at the working concentration of 12.5μg/mL. The above results suggest a potent anti-HSV-1 activity of the alkaloids extract in vitro. 展开更多
关键词 Tripterygium hypoglaucum Herpes complex virus ALKALOID Antiviral activity Gene expression
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Serial imaging of human embryonic stem-cell engraftment and teratoma formation in live mouse models 被引量:9
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作者 Martin G Pomper Holly Hammond +5 位作者 Xiaobing Yu Zhaohui Ye Catherine A Foss Doris D Lin James J Fox Linzhao Cheng 《Cell Research》 SCIE CAS CSCD 2009年第3期370-379,共10页
Two new types of lentiviral vectors expressing a reporter transgene encoding either firefly luciferase (fLuc) for bioluminescence imaging or the HSV1 thymidine kinase (HSV1-TK) for radiopharmaceutical-based imagin... Two new types of lentiviral vectors expressing a reporter transgene encoding either firefly luciferase (fLuc) for bioluminescence imaging or the HSV1 thymidine kinase (HSV1-TK) for radiopharmaceutical-based imaging were constructed to monitor human embryonic stem cell (hESC) engraftment and proliferation in live mice after trans- plantation. The constitutive expression of either transgene did not alter the properties of hESCs in the culture. We next monitored the formation of teratomas in SCID mice to test (1) whether the gene-modified hESCs maintain their developmental pluripotency, and (2) whether sustained reporter gene expression allows noninvasive, whole-body imaging of hESC derivatives in a live mouse model. We observed teratoma formation from both types of gene-modified cells as well as wild-type hESCs 2-4 months after inoculation. Using an optical imaging system, bioluminescence from the fLuc-transduced hESCs was easily detected in mice bearing teratomas long before palpable tumors could be detected. To develop a noninvasive imaging method more readily translatable to the clinic, we also utilized HSV1-TK and its specific substrate, 1-(2'-deoxy-2'-fluoro-β-D-arabinofuranosyl)-5-[^125I]iodouracil([^125I]FIAU), as a reporter/ probe pair. After systemic administration, [^125I]FIAU is phosphorylated only by the transgene-encoded HSV1-TK enzyme and retained within transduced (and transplanted) cells, allowing sensitive and quantitative imaging by single-photon emission computed tomography. Noninvasive imaging methods such as these may enable us to monitor the presence and distribution of transplanted human stem cells repetitively within live recipients over a long term through the expression of a reporter gene. 展开更多
关键词 pluripotent stem cells ESCS optical imaging SPECT PET TERATOMA
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Fresh views on some recent developments in the simplex algorithm
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作者 胡剑峰 潘平奇 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期124-126,共3页
First, the main procedures and the distinctive features of the most-obtuse-angle(MOA)row or column pivot rules are introduced for achieving primal or dual feasibility in linear programming. Then, two special auxilia... First, the main procedures and the distinctive features of the most-obtuse-angle(MOA)row or column pivot rules are introduced for achieving primal or dual feasibility in linear programming. Then, two special auxiliary problems are constructed to prove that each of the rules can be actually considered as a simplex approach for solving the corresponding auxiliary problem. In addition, the nested pricing rule is also reviewed and its geometric interpretation is offered based on the heuristic characterization of an optimal solution. 展开更多
关键词 linear programming simplex algorithm PIVOT mostobtuse-angle nested pricing large-scale problem
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