风险投资是新三板市场“积极的投资者”吗

定向增发在新三板创业企业的股权融资中发挥着中坚作用,而风险投资正是其中重要的参与者。本文选择2013—2016年新三板企业定向增发为研究样本,实证检验了风险投资介入的动因及经济后果。研究发现,整体而言,风险投资参与新三板定向增发会选择财务绩效较好、创新能力较强的企业介入,结论支持了风险投资的事前筛选职能。大股东参与定向增发在一定程度上会减弱风险投资介入与企业财务绩效和创新能力之间的敏感性。当面对优质企业标的时,风险投资将选择联合投资的方式\"抱团\"进入,体现了其在新三板市场更为谨慎的投资风格。但风险投资进入所投企业后,受制于本身能力和投资意愿,并未显著提升被投企业财务绩效和创新能力,没有发挥事后监督职能。考虑新三板独特的做市商制度和分层制度,本文再次验证了风险投资事前筛选职能的履行和事后监督职能的缺失。本文不仅揭示了风险投资参与新三板企业定向增发的动因及经济后果,同时也为国家利用新三板市场推进创新战略、构建和完善多层次资本市场提供了经验证据。国家自然科学基金面上项目“新三板企业挂牌、定增与做市交易问题研究:基于风险投资的视角”(71673231);国家自然科学基金青年科学基金项目“风险投资声誉作用机制研究——基于投资机构和创业企业的视角”(71502103

ULTRASTRUCTURAL STUDIES ON MEMBRANED INCLUSIONS IN THE CELLS of MERISTEMATIC REGIONS of STEVIA REBAUDIANA CALLUS

生长在分化培养基上的甜菊（STEVTTIrEbAudIAnA）愈伤组织分生区细胞中存在双膜和多膜内含物。电镜观察表明，这些膜内含物是由一圈或多圈呈同心圆或卷绕状排列的内质网包围部分细胞质而形成的。双膜内含物内外层膜的靠细胞质表面有核糖体附着，而多膜内含物仅在其最外层储油的外膜上偶有少量核糖体附着。随着细胞液泡化程度的提高，多膜内含物通过液泡膜内陷而转移到液池中或通过消化其中被包围的细胞质及内膜而转化为小液泡。此外，还观察到内质网潴泡膨大直接形成小池，有时在其外表面附有核糖体，且通过界膜的局部内陷吞噬部分细胞质。结果表明，某些内质网参与了对部分细胞质的分隔及继后的降解，而这对于甜菊愈伤组织器官分化前的细胞改建中细胞质组分的正常更新可能是必需的。The presence of both double and multiple membraned inclusions were observed inthe cells From the meristematic regions Formed in callus cultures of Stevia rebaudiana ondiFFerentiating medium.It was Found that these membraned inclusions appear to be de-rived From the endoplasmic reticulum elements which arrange themselves in a multiple-concentric or convoluted manner around portions of cytop1asm or Form a ring enclosingareas of cytoplasm.The doublemembraned inclusions have ribosomes attached to the cy-toplasmic surFaces of both the outer and the inner membranes, while the multimem-braned inclusions show a Few ribosomes attached occasionally to the outer membrane ofthe outermost cisterna.As cellular vacuolation progresses,the multi-membraned inclu-sions are transFerred to the enlarging vacuoles by tonoplast invagination or transFormed into small vacuoles by the digestion of the sequestered cytoplasm and inner membranes.In addition,vesicles can be Formed directly by the dilation of the endoplasmic reticulumcisternae,which,in some cases,bear ribosomes on the outer surFace and engulF a portionof cytoplasm by local invagination of the limiting membrane.The results indicate thatcertain endoplasmic reticulum cisternae are engaged in the sequestration and subsequentdigestion of cytop1asm which may be required For the normal turnover of cytoplasmiccomponents in the cellular remodeling which precede organ diFFerentiation in the cul-tured callus of Stevia rebaudiana

Te掺杂对MoPO/SiO_2催化剂上丙烷选择氧化制丙烯醛反应的影响

考察了Te的添加及Te含量对MoPO/SiO2催化剂催化丙烷选择氧化制丙烯醛反应性能的影响.MoPO/SiO2催化剂对丙烷选择氧化制丙烯醛反应的中间产物丙烯选择性较高,而Te的添加促进了丙烯向丙烯醛的转化.N2吸附、XRD、Raman、XPS、H2-TPR、丙烷脉冲、NH3-TPD和Py-IR等实验结果表明,催化剂添加Te后虽然比表面积有所下降,但单位比表面积上的酸量增加,催化剂低温可还原性得到改善,从而有利于丙烷的转化.Te可能有利于丙烯α-H的脱除和/或烯丙基的插氧反应

浆态法制备的MoVTeNbO催化剂上的乙烷氧化脱氢(英文)

采用浆态法在N2 气氛下焙烧制得了MoV0 .3 Te0 .2 3 Nb0 .1Ox 催化剂.在以该催化剂催化的乙烷氧化脱氢制乙烯的反应中,4 4 0℃下乙烷的转化率和乙烯的选择性均在90 %左右,乙烯产率达80 9% .但在空气气氛下焙烧得到的催化剂几乎没有催化活性.用XRD和SEM等方法考察了催化剂的结构

太阳能利用中的跟踪控制方式的研究

对太阳能利用中的开环、闭环和混合控制跟踪控制方式的特点进行了分析。通过计算几种单轴跟踪方式的跟踪角，根据跟踪角和太阳的时角间的关系，对单轴跟踪时的控制方式的选择进行了研究。特别是使用了MATLAB程序处理数据，得到南北水平轴跟踪时跟踪角和太阳时角间的关系图像，着重分析了此时采取混合跟踪的可行性和适用性。对几种跟踪控制方式的优缺点进行了分析和总结，分析了他们的特点和适用性

抛物柱面聚焦的几种跟踪方式的光学性能分析

通过建立的模型计算瞬时太阳直射辐射强度，求出了各种跟踪方式下的太阳光入射角，算出各种跟踪方式下抛物镜开口接收的瞬时太阳直射辐射能，并使用MATLAB处理数据，作出了广州地区在不同季节的辐照度变化图以及广州、北京地区一年中日辐射总量变化图，通过分析图像和数据，对几种跟踪方式的光学性能以及纬度对各种跟踪方式光学性能的影响进行了分析、研究。最后对各种跟踪方式系统使用时遇到的问题进行了讨论

Venture Capital will Affect the Market Making Transfer Behavior of Firms?——Based on the Empirical Research of the NEEQ in China

本文基于新三板市场,考察了风险投资是否对新三板企业做市转让行为产生影响。研究发现,整体而言,风险投资支持的挂牌企业更有可能进行做市转让。其中,高声誉、非国有背景风险投资在企业做市转让过程中发挥更大的作用。此外,风险投资尤其是非国有背景风险投资支持的企业拥有更多的做市商数量,体现了更强的做市动机。结论支持了风险投资监督管理的价值增加效应。进一步研究发现,在新三板做市交易低迷情况下,风险投资不再积极推动所投企业进行做市转让。综合研究结论,企业选择声誉更好、非国有背景的风险投资机构更有利于企业做市转让。In recent years,NEEQ,which is an important part of the multi-level capital market in China,has become the third national stock exchange gradually for its rapid development,following Shanghai and Shenzhen Stock Exchange.And the market maker system is introduced into the NEEQ to improve the liquidity of the market as well as realizing the value of the discovery.Afterwards,more and more listed companies begin to change from agreement transfer to market making transfer.More than 1400 companies adopt market making transfer by the end of March,2016,accounting for 22% of the total listed companies.As an important carrier of service innovation and entrepreneurship,venture capitals also experience a rapid development recently.The statistics from the Zero2 IPO Group show that by the end of 2015 more than 8000 VC / PE institutions remain active in capital market.At the same time,venture capital plays an increasingly important role in the NEEQ,since 474 firms have listed in the NEEQ with venture capital background by the end of March,2016.There are three stages for investment and management and exit of venture capitals,namely Value found,value creation and value realization( Li Yao & Wang Xiujun,2015).In the stage of value creation,venture capitals play a supervisory role in the IPO stage of firms invested.Different from main board,SME and GEM,NEEQ is a new capital market.Landing in the NEEQ and realizing the market making transfer are an important step in pre IPO of firms,which can create the condition for venture capitals to have added value on the firms' supervising and management.In order to investigate whether venture capitals have an impact on the market making transfer of firms,this paper deeply analyzes and discusses the following two problems:Firstly,whether venture capitals can improve the probability of the market making transfer of firms and make more market makers provide the market making for the firms overall? What are the effects of the mechanism? Secondly,further,what are the differences among venture capitals in different backgrounds and different reputations on supporting the market making transfer of firms and the number of market makers? To deal with above problems,this paper collects the relevant data of venture capitals through the Wind database for empirical test and gets the corresponding conclusion,based on the research sample of6349 listed companies in the NEEQ from 2006—2016.The main results are as follows:( 1) Overall,venture capitals play an essential role in supervision,management and certification.Firms are more probable to adopt market making transfer if they have venture capitals support,and those firms also have more market makers,which shows it is important for firms to do the market making transfer.( 2) Venture capitals that have different characteristics play a different role on market making transfer of the firms.Firms with high reputation and non-state-owned background venture capitals are more likely to make market making transfer.At the same time,non-state-owned background venture capitals can stimulate firms to have more market makers,but high reputation VCs do not arrive the same conclusion.High reputation and non-state-owned background venture capitals are also found to play a certain role through group inspecting,which further verify the motivation and ability of the non state backed venture capitals.( 3) Although the result that the downturn of the NEEQ will reduce venture capitals to the market making transfer of firms is not significant,it can still indicate that the desire that venture capitals promote the market making transfer of firms is different.国家自然科学基金面上项目“新三板企业挂牌、定增与做市交易问题研究:基于风险投资的视角”(71673231);国家自然科学基金面上项目“风险投资支持的企业IPO折价、择机与后管理问题研究”(71172052);; 中央高校基本科研业务费专项资金资助项目“管理者异质性对公司财务决策的影响研究”(20720151180

AFLP analysis of genetic structure of Boleophthalmus pectinirostris populations from the coastal waters of Northwest Pacific

应用AflP标记分析了西北太平洋沿岸大弹涂鱼(bOlEOPHTHAlMuS PECTInIrOSTrIS)的遗传多样性和群体结构。利用6对选择性引物对采自日本、韩国、越南及中国广西、广东、福建、台湾和浙江8个群体的126尾大弹涂鱼进行扩增。在15~500 bP之间得到186条条带,其中多态性片段160条,多态性比例为86.02%,每对引物组合扩增片段为25~36条,每对引物组合多态位点检出率为52.0%~96.42%。各群体的多态性位点比例在27.96%~57.53%之间,其中韩国群体的多态性位点比例最高,广东群体的多态性位点比例最低。各群体间nEI’S遗传距离为0.038~0.151,遗传距离较大。各群体间遗传分化指数fST值为0.175~0.459,均检测到显著的遗传分化(P=0.000)。基于遗传距离矩阵构建的nJ系统树显示,大弹涂鱼的8个群体被分为了两支,其中日本、韩国及台湾群体聚为岛屿支系,浙江、福建、广东、广西和越南群体聚为大陆支系。AMOVA分析显示,大部分的变异组分来自于各群体内个体间,且组群间、群体间及群体内均存在明显的遗传分化。群体间遗传分化系数gST为0.385 7,群体间的基因流nM为0.796 4,群体间基因交流弱于其他多数鱼类。The mudskipper(Boleophthalmus pectinirostris) is an amphibious fish, adapting to a wide range of temperature and salinity.It inhabits the mudflats of intertidal zone and the mangrove forests in China, Korea, Japan, Vietnam and Malaysia.In China, it is mainly found in coastal mudflats of Zhejiang, Fujian, Taiwan, Guangdong and Guangxi provinces.Due to its economic importance, this species is widely cultured in southeast China.In the past 30 years, its natural resource has decreased gradually due to overfishing, loss and fragmentation of its natural habitats and environmental pollution.Genetic diversity of this species has been previously studied, but the samples were only obtained from a certain range of its habitats.In this study, amplified fragment length polymorphism(AFLP) markers were used to analyze the genetic diversity of 8 B.pectinirostris populations from the coastal waters of Northwest Pacific, in an attempt to illustrate its phylogeographic patterns and genetic structure.The findings of this study will provide insights into the future fishery management and conservation for B.pectinirostris.Instead of the traditional method polyacrylamide gel electrophoresis(PAGE), QIAxcel DNA High Resolution Kit Gel Cartridges was used to perform the AFLP analysis.Among the 126 individuals from the 8 populations in Japan, Korea, Vietnam and Guangxi, Guangdong, Fujian, Taiwan, and Zhejiang provinces of China, 186 loci between 15 bp and 500 bp were detected using 6 selective amplification primers(E-AGC/M-CTG, E-AGC/M-CCA, E-ATG/M-CCA, E-ATG/M-CTT, E-ACT/M-CAC, E-AGG/M-CTT), and 160 of which were polymorphic(86.02%).The amplified bands ranged from 25 to 36 for each primer combination.On the other hand, the detecting rates of each primer varied from 52.0% to 96.42%, with E-ACT/M-CAC showing the lowest detecting rate of 52.0% while other primers were all above 82%.The proportion of polymorphic loci from 8 populations varied from 27.96% to 57.53%, with the highest one for Korea population and the lowest one for Guangdong(China) population.The polymorphic loci proportion of B.pectinirostris were much lower than those of other fish species.Overfishing, habitats loss and environmental pollution may be the reasons for the low genetic diversity of B.pectinirostris.Nei's distances between populations were from 0.038 to 0.151.The highest genetic distance was observed between Taiwan and Guangxi populations while the lowest was observed between Zhejiang and Guangdong populations.The pairwise comparisons of Fst ranged from 0.175 to 0.459, all of which were statistically significant(P=0).NJ tree constructed on the base of genetic distances between populations showed that the 8 populations were divided into two groups(A and B).Group A included Japan, Korea and Taiwan populations while Group B included the populations from Zhejiang, Fujian, Guangdong, Guangxi Provinces and Vietnam.The analysis of molecular variance showed that 15.48% of the total genetic variance was contributed by the among groups variation(Fct=0.15, P<0.01), 62.06% within populations variation(Fst=0.38, P=0) and 22.46% among populations within groups variation(Fsc=0.27, P=0).Coefficient of population differentiations(Fst) was 0.385 7 and the geneflow(Nm) from Gst was 0.796 4, which were comparatively lower than those of most other fish species.Also, strong genetic divergence between the populations of B.pectinirostris was found based on the pairwise comparisons of Fst and Nm.In comparison with the other marine migration fish, B.pectinirostris live in burrows on the mudflats of intertidal zone and do not have the feeding and spawning migration habits in their life cycle.Accordingly, their dispersal ability is very poor, leading to genetic differentiation between their populations.Since Japan, Korea and Taiwan are islands or peninsula, the habitats of B.pectinirostris populations in these locations are geographically different from those of the continental populations.Hence, genetic exchanges among them are very difficult to realize.国家自然科学基金项目(40976095); 厦门南方海洋研究中心项目(13GST001NF13); 厦门大学校长基金(2013121044

The Study of Stevia glucoside Change in Stevia Tissue Culture

研究了甜菊组培过程中 ,甜菊苷 (Stevioside,缩写为 SS)和丽鲍迪苷 A(Rebaudioside,缩写为RA)两种主要甜味成份的变化以及不同浓度的 6 -卞氨基腺苷 (6 - BAP)对愈伤组织合成 SS及 RA的影响 ,并初步探讨了根部在糖苷合成过程中的作用 .结果表明 :甜菊愈伤组织合成糖苷的能力随培养时间的不同而异 .培养 10 d的愈伤组织可检测到少量残余叶片的 SS及 RA,而培养 2 0 d,30 d的愈伤组织则未检出 .培养 4 0 d的愈伤组织仅检测到 RA,表明此时的愈伤组织又恢复了合成糖苷的能力 ,推测与叶绿体的再分化有关 .在含有不同浓度 6 - BAP的培养基中培养 2个月的愈伤组织都能够合成糖苷 ,但所合成糖苷的组分不同 .其中 ,在含有 0 .5mg/L,1mg/L,2 mg/L 6 - BAP培养基中的愈伤组织只能积累 RA,且随浓度的增加 ,RA的含量逐渐降低 ;而含有 3mg/L 6 - BAP培养基中的愈伤组织只能合成 SS.有根苗可合成 SS及 RA.而无根腋芽苗只能合成 SSThe changes of two main sweet content, Stevioside(SS) and Rebaudioside (RA),the effects of 6 benzylaminopurine riboside(6 BAP) on the two sweet content in callus of stevia rebaudiana, as well as the role of root in the process of stevioside biosynthesis have been studied.the result showed that the ability for stevioside biosynthesis of callus altered with the lapse of cultural time; when cultured 10 days, Trace SS and RA were tested on callus. 20、30 days later,neither SS nor RA were tested, which indicated the callus had no ability for stevioside biosynthesis.But 40 days later,only RA was synthetized. It seems that the stevioside biosynthesis is related to re differentiation of chloroplast.when cultured 60 days later,all the callus with different concentration 6 BAP do have ability to synthetize SS or RA.The callus in culture with 0.5 mg/L,1 mg/L, 2 mg/L 6 BAP can only synthetize RA, while the callus with 3mg/L 6 BAP only sythetize SS.The rooted seedling demonstrated the ability to synthetize both SS and RA,Shooted seedling only to synthetize SS.福建省自然科学基金资助项目!(C970 0 7