国内外“科学-技术关系”研究方法述评——聚焦文献计量方法

[目的/意义] 鉴于"科学-技术关系"是情报学领域的热点研究问题,文献计量方法是研究该问题的常用方法,对国内外研究该问题的主要文献计量方法进行述评,就如何更好地运用这些方法进行"科学-技术关系"研究提出建议。[方法/过程] 在回顾"科学-技术关系"的含义和相关研究方法的基础上,梳理和总结专利的论文引文分析法、论文的专利引文分析法、"专利发明人-论文作者关联关系"分析法3种主要文献计量方法在"科学-技术关系"研究方面的应用和国内外进展,比较3种方法的理论基础、应用范围和存在的问题。[结果/结论] 3种方法基于不同的理论基础,分别被应用于:①识别与科学领域关系较强的技术领域;②识别被科学领域引用较多的技术领域、国家和机构;③测度专利发明人的科学研究活动、大学和企业的合作情况。这些方法分别存在专利的施引动机不明确、专利的论文引文字段不规范、数据较少、主题分析和技术对科学的作用机理研究较少、专利发明人和论文作者名称难以识别和匹配等问题。研究"科学-技术关系"时需根据研究问题和数据特征等选择合适的文献计量方法,并注意解决这些方法存在的问题。     

日本骈文述略(上)

日本最早的骈文是圣德太子所著《道后温泉碑文》,这是今存日本的第一篇汉文游记,亦即最早的纯汉文学作品。刀利康嗣《释奠文》是现今能见到的日本最古老的祭孔文,同时也是儒学东传史上的重要文献。淡海三船《怀风藻》的序文叙述日本汉文学发展简史,是很有价值的重要文献,也是成熟的骈体论说文。     

日本骈文述略(下)

日本骈文的发展,一直延续到十二世纪。而菅原道真、纪谷长雄和三善清行可以代表前一个时代,而与上述三人相差二三十年的纪贯之,则属于后一个时代。     

Hybrid capillary-inserted microfluidic device for sheathless particle focusing and separation in viscoelastic flow

A novel microfluidic device which consists of two stages for particle focusing and separation using a viscoelastic fluid has been developed. A circular capillary tube was used for three-dimensional particle pre-alignment before the separation process, which was inserted in a polydimethylsiloxane microchannel. Particles with diameters of 5 and 10 μm were focused at the centerline in the capillary tube, and the location of particles was initialized at the first bifurcation. Then, 5 and 10 μm particles were successfully separated in the expansion region based on size-dependent lateral migration, with ∼99% separation efficiency. The proposed device was further applied to separation of MCF-7 cells from leukocytes. Based on the cell size distribution, an approximate size cutoff for separation was determined to be 16 μm. At 200 μl/min, 94% of MCF-7 cells were separated with the purity of ∼97%. According to the trypan blue exclusion assay, high viability (∼90%) could be achieved for the separated MCF-7 cells. The use of a commercially available capillary tube enables the device to be highly versatile in dealing with particles in a wide size range by using capillary tubes with different inner diameters.     

论大学校园文化中的公寓文化建设

公寓文化是校园文化的重要组成部分。目前在校园文化特别是公寓文化建设中存在着一些问题,如学校对公寓文化建设重视不够,公寓文化活动仍处于自发性和盲目性状态,缺乏有效的管理监督机制,内涵相对贫乏,网络文化的消极影响严重等。高校应加强对学生公寓的管理,在提升公寓后勤管理队伍的整体素质的同时,通过加强公寓硬件、精神文明、管理服务等方面的建设,营造一个优秀健康、和谐向上的大学生公寓文化氛围,促进大学生的全面健康发展。     

贵州金沙方言与普通话声母之对比

金沙方言属于西南官话川黔片成渝小片,虽然其基本特点与普通话一致性较高,但其语音、词汇、语法与普通话都存在一定的差异。就语音方面的声母看,两者共同的声母有17个,普通话特有的声母有5个,金沙方言特有的声母有3个。金沙方言特有的声母与普通话有比较复杂的对应关系,厘清这种对应关系,对于金沙方言区的人学习和推广普通话具有一定现实意义。     

大学生英语口语学习困境与对策

欠发达地区新建地方高校的大学生英语口语学习始终难以克服本土化困境,如语言环境差、高中英语学习的惯性、特殊的心理障碍、教育评价系缺失等不利因素一直制约着他们英语口语学习成效的提高.大学生们只有针对这些在在的问题,有针对性地加以解决,才能提高英语口语的交际能力.     

茶树中咖啡酰辅酶A氧甲基转移酶的基因克隆及其催化活性研究(英文)

目的:从茶树中克隆一种可以催化表没食子儿茶素没食子酸酯(EGCG)生成甲基化EGCG的酶——咖啡酰辅酶A氧甲基转移酶(CCo AOMT),实现甲基化EGCG的酶学合成,为甲基化EGCG的进一步开发利用提供理论依据和技术指导。创新点:本研究首次从茶树中克隆了一条CCo AOMT基因组序列;分析了CCo AOMT基因在不同茶树品种和不同成熟度茶鲜叶中的基因表达规律;证明了CCo AOMT具有催化合成甲基化EGCG的生物活性。方法:采用聚合酶链式反应(PCR)和序列分析获得CCo AOMT的编码序列和基因组序列;采用高效液相色谱-四级杆-飞行时间串联质谱技术(HPLC-QTOF-MS)分析酶促反应生成的甲基化EGCG产物(图4);采用实时荧光定量PCR分析CCo AOMT基因的表达差异(图5)。结论:本研究从茶树中克隆了CCo AOMT基因的编码序列(738 bp)和基因组序列(2678 bp),明确了该基因具有4个内含子和5个外显子;揭示了CCo AOMT可以催化EGCG生成EGCG4"Me、EGCG3"Me和EGCG3’Me等多种甲基化产物;证明了CCo AOMT具有催化生成甲基化EGCG的活性;并发现该基因的表达量高低与茶鲜叶的成熟度呈正相关关系。     

Effect of microcystin-LR on protein phosphatase 2A and its function in human amniotic epithelial cells

Due to their toxicity, the increased distribution of microcystins (MCs) has become an important worldwide problem. MCs have been recognized as inhibitors of protein phosphatase 2A (PP2A) through their binding to the PP2A catalytic subunit. However, the exact mechanism of MC toxicity has not been elucidated, especially concerning the cellular response and its autoregulation. To further dissect the role of PP2A in MC-induced toxicity, the present study was undertaken to determine the response of PP2A in human amniotic epithelial (FL) cells treated with microcystin-LR (MCLR), one of the MC congeners. The results show that a low-dose treatment of MCLR in FL cells for 6 h induced an increase in PP2A activity, and a high-dose treatment of MCLR for 24 h decreased the activity of PP2A, as expected. The increased mRNA and protein levels of the PP2A C subunit may explain the increased activity of PP2A. Furthermore, MCLR altered microtubule post-translational modifications through PP2A. These results further clarify the underlying mechanism how MCLR affects PP2A and may be helpful for elucidating the complex toxicity of MCLR.     

Cloning and efficient expression of <Emphasis Type="Italic">Bacillus sp.</Emphasis> BH072 <Emphasis Type="Italic">tasA</Emphasis> gene in <Emphasis Type="Italic">Escherichia coli</Emphasis>

The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein.