Empirical Study on Herd Behavior of China's Securities and lnvestment Funds

基于2 0 0 3年3月-2 0 0 5年3月之间中国开放式基金的投资组合的数据进行分析,运用wermers(1 9 9 9)对于LSV模型的羊群行为测度的修正方法,对基金持有的股票进行各种特征的分类的羊群行为测度,得出中国存在比较严重的羊群行为。从对基金持有股票的特征分析得出羊群行为在高收益的小股票和上期回报率高、下期回报率高的股票上程度也比较明显。从基金成立日、投资类型分析得出新基金、股票型的基金的羊群行为程度高。而利用下期回报率对羊群行为的理性和非理性进行分析得出中国的开放式基金可能为假羊群行为的结论。 Abstract : Based on the data of the investment portfolios from March 2003 to March 2005 , by using the Wermers (1999) modified LSV model , this paper measures the herd behavior in the stocks hold by the funds according to various sorted characteristics ,and concludes that there is rather severe herd behavior . From analyses of the characteristics of the stocks hold by funds , it shows that herd behavior is obvious in the stocks with high earning , small cap , high previous return and high next return1 From analyses of the date of foundation and types of investment , it shows that herd behavior in new and equity funds is in high degree1 And from analyses of the rationality and irrationality of herd behavior by the next period return , the conclusion is that herd behavior in China’s open funds may be not true

Study on synthesis and application of 17β-Estradiol molecularly imprinted composite membrane

以多孔乙酸纤维膜为载体,17β-雌二醇为模板,采用紫外光引发制备了17β-雌二醇乙酸纤维分子印迹复合膜。试验对膜的选择吸附性和分离透过性进行了探讨。实验结果表明,所合成的乙酸纤维分子印迹复合膜对模板分子17β-雌二醇具有较好的选择吸附性,吸附量达10.2μMOl/g;17β-雌二醇/17α-炔雌醇的分离因子为4.7。膜透过实验表明,该分子印迹复合膜能将17β-雌二醇与17α-炔雌醇分离开,表明17α-炔雌醇作为结构类似物在复合膜上的结合牢固性不如模板分子。In this paper,the 17β-Estradiol molecularly imprinted composite membrane through UV initiation was prepared by using porous cellulose acetate membrane as support.The selective binding properties and separation capacity of the membranes were investigated.The results showed that the 17β-Estradiol molecularly imprinted composite membrane had high binding capacity for 17β-Estradiol,the binding amount Q for 17β-Estradiol was 10.2 μmol/g and separation factor was 4.7 for 17β-Estradiol/17α-ethinylestradiol.Permeation experiment results showed that the molecularly imprinted composite membrane could separate 17β-Estradiol from 17α-ethinylestradiol.The bonding force between 17α-ethinylestradiol and the membrane was weaker than the template.福建省教育厅B类项目(JB09241

Several Noether's theorem of Vacco systems with constraints

研究受约束Vacco系统的Noether对称性 .基于受约束Vacco系统在r 参数有限变换群Gr 的无限小广义准对称变换下的不变性 ,给出了受单面约束的Vacco系统的Noether定理及其逆定理 .受双面约束的Vacco系统的Neother定理为该定理的推论 .最后给出一个算例说明了结果的应用 .The Neother symmetry for Vacco systems with constraints is studied. Noether's theorem and its inverse theorem of Vacco systems with unilateral constraints are given,which are based upon the invariant properties by introducing the generalized quasi-symmetry of the infinitesimal transformation for the transformation group G r of r -parameter. And Noether's theorem dealing with the Vacco system of bilateral constraints is its corollary. An example to illustrate the application of the result is given.安徽省高校自然科学基金资助项目 (2 0 0 2kj2 3 0,2 0 0 4kj2 94

ERK干扰质粒的构建及对胃癌细胞株BGC823 DcR3表达的影响

目的探讨胃癌发展的分子机制,通过构建ERK1/2shRNA真核表达载体,体外研究其对人胃癌细胞株BGC823ERK1/2蛋白及DcR3表达水平的影响。方法应用PRNAT-U6.1/Neo载体构建ERK1/2基因shRNA重组质粒,经脂质体法导入BGC823细胞中,分别设置对照组、干扰组和U0126抑制剂组。Westernblot法检测转染后BGC823细胞及抑制剂使用后ERK1/2蛋白的表达变化,荧光显微镜检测质粒自带GFP基因的表达情况确认转染效率,ELISA法检测各组细胞上清中DcR3分泌蛋白的表达特点。结果成功构建ERK1/2基因shRNA重组质粒。证明了ERK1/2蛋白的表达与DcR3的分泌水平在BGC823细胞株中呈正相关。结论 ERK1/2干扰质粒明显降低BGC823细胞的ERK1/2蛋白表达水平,ERK信号通路对DcR3的分泌具有重要调控作用,为其下游调控机制的研究奠定了基础

激光作用产生离子引发的苯乙烯聚合

激光作用产生离子引发的苯乙烯聚合邹友思，林国良，黄荣彬，刘朝阳，郑兰荪（厦门大学化学系固体表面物理化学国家重点实验室，３６１００５）近年来，以高能量密度的脉冲激光束在高真空中溅射固体样品，已成为产生原子簇正负离子的一种有效手段。１９９３年，美国化学家..

Self-Cleaning Glass Antireflection Films Prepared by Sol-Gel Method

在酸催化体系中以正硅酸乙酯(TEOS)和纳米锐钛矿型二氧化钛粉末为SIO2-TIO2复合溶胶原料,采用提拉法在高硼硅玻璃基片表面制备出具有增透和自清洁功能的薄膜。研究了制备工艺对薄膜增透和光致超亲水性能的影响。制备的样品在400~800 nM波段,光线垂直入射时,透射率增加3%,紫外光照射一定时间后,样品对水接触角不超过5°,具有光致超亲水作用。The self-cleaning glass antireflection film was prepared on the surface of high borosilicate glass substrate by using TEOS and nanometer anatase type of titanium dioxide powder as sol-gel SiO2-TiO2 composite raw materials and using Czochralski method.The effect of preparing technique on antireflection and photoinduced super hydrophilicity properties was investigated.The experiments show that the light transmittance of prepared sample increased about 3% at wavelength between 400nm and 800nm under light vertical incidence.After UV irradiation for a certain time,the water contact angle was ≤5° which exhibited the characteristic of photoinduced super hydrophilicity.福建省区域科技重大项目(2011H41010083

RGD-FasL羟乙基壳聚糖缓释纳米粒制备及生物学研究

目的使用羟乙基壳聚糖制备纳米颗粒(NPs),用来包载RGD-FasL融合蛋白(RF),鉴定其功能并评估其在肝癌治疗中的作用。方法采用离子凝胶法制备RF羟乙基壳聚糖缓释纳米粒(RF-NPs);通过透射电镜、动态光散射法考察其理化性质;用紫外分光光度仪检测蛋白浓度来计算其载药率、包封率和体外释放度;通过MTT比色法检测对H22细胞增殖活性的影响,应用H22细胞建立小鼠肝癌模型进行体内抑瘤研究。结果制备的RF-NPs呈球形或类球形,平均粒径198.3 nm,Zeta电位+25 mV,包封率较高,且具有缓释效果,150 mg/L浓度时对H22细胞抑制率大于70%,并能在小鼠体内产生比较明显的抑瘤效果。结论离子凝胶法制备RF-NPs的条件缓和、方法简单,是癌症治疗中具有很好的前景的蛋白药物载体

羟乙基壳聚糖抗人死亡受体5单链抗体纳米粒的制备、鉴定及体内抑瘤研究

目的为提高抗人死亡受体5单链抗体治疗肝癌的效果,探讨羟乙基壳聚糖抗人死亡受体5单链抗体纳米粒(GCS-aDR5ScFv)的制备、鉴定并研究其对小鼠肝癌H22模型的治疗效果及机制。方法用亲和镍柱层析法纯化抗人死亡受体5单链抗体(aDR5ScFv),采用离子凝胶法制备GCS-aDR5ScFv,应用扫描电镜来检测GCS-aDR5ScFv的外观形态,激光粒度分析仪分析纳米粒的粒径及粒径分布,并检测其表面Zeta电势。建立小鼠肝癌H22模型,用0.272 mg/ml GCS-aDR5ScFv隔天治疗并测量小鼠体质量及肿瘤大小,治疗2周。通过Western blot检测active-caspase8、active-caspase3及BAX表达。结果纯化的aDR5ScFv符合理论条带(Mr30 000),GCS-aDR5ScFv纳米粒形态均一,纳米粒径大小、Zeta电势和多分散指数表明GCS-aDR5ScFv稳定。与正常组相比,治疗组小鼠体质量显著差异,治疗组肿瘤体积和大小差异显著。Western blot检测active-caspase8、active-caspase3、BAX的表达水平上调。结论本研究制备的GCS-aDR5ScFv稳定,对小鼠肝癌H22模型具有抑瘤作用,其机制可能与active-caspase8、active-caspase3及BAX蛋白表达上调相关

Assessing ecological risks of heavy metals to marine organisms in the Jiulongjiang Estuary by species sensitivity distribution

采用物种敏感性分布法(SSd)构建常见重金属元素对海洋生物的SSd曲线,结合九龙江口水体5、8、11月份21个站位重金属调查数据,计算了九龙江口7种重金属(AS,Cd,Cr,Cu,Hg,Pb,zn)不同暴露浓度对海洋生物的潜在影响比例(PAf),并分析了在相应站位重金属复合污染生态风险(MSPAf)。结果表明,7种重金属中AS的生态风险最大(即PAf值最高);时间尺度上,5月份总的MSPAf较其他月份稍高;空间尺度上,西溪至海门岛(1~7号站位)污染较严重,其中又以位于西溪和玉枕洲的2号和5号站位的MSPAf为最。In the present work,a species sensitivity distribution( SSD) method was used to assess the ecological risk of common heavy metals to marine organisms.The ecological risk was characterized by potentially affected fraction( PAF) of species in relation to concentration of the toxic materials.According to the investigation data obtained at 21 stations in the Jiulongjiang Estuary in May,August and November,the PAFs of seven heavy metals( As,Cd,Cr,Cu,Hg, Pb,and Zn) to marine organisms were calculated.The results showed that As had the highest PAF among the seven heavy metals at each station of the Jiulongjiang Estuary.Spatially,the multi-substance PAF( msPAF) in May was higher than in other months.Temporally,the msPAF of the Stations 1-7( from the Xixi Stream to the Haimen Isle of the Jiulongjiang Estuary) suffered from heavier pollution.In particular,the pollution status of the Station 2 and Station 5 was the most serious among all the investigated stations.海洋公益性行业科研经费专项(201105015); 国家海洋局青年海洋科学基金项目(2011143); 国家自然科学基金项目(31101902); 福建省自然科学基金项目(2012J05074); 国家海洋局第三海洋研究所基本科研业务费专项(海三科2011006)资

2018年安溪珠塔内窑调查报告

2018年5月至7月,厦门大学历史系考古专业、福建博物院文物考古研究所及安溪县博物馆等单位联合组成\"安溪古窑址调查队\",对安溪珠塔内窑进行了全面的调查,基本了解珠塔内窑古窑址分布与保存情况,采集了一批明末清初的青花瓷器、白瓷与窑具标本,并发现部分窑炉遗迹,为研究闽南地区青花瓷窑业发展提供了第一手资料