风险投资、区域创新与创新质量甄别

利用基于风险投资案例和专利申请与授权的中国省际面板数据,研究了风险投资对区域技术创新产出的促进作用和风险投资在"研发投入—创新产出"转化过程中的创新质量甄别效应。研究发现:(1)风险投资促进了中国区域技术创新产出,并呈现出滞后效应和"倒U型"趋势,其在滞后二期和三期显著性水平和创新效果达到最优;(2)风险投资对经济和科技欠发达的西北与东北地区创新产出促进效果最佳,而对经济和科技较发达的东部和中部地区创新产出促进作用不明显;(3)风险投资甄别了创新产出的质量,其有效抑制研发投入转化为以外观设计和实用新型为代表的低质量创新产出,而积极促进研发投入转化为以发明专利为代表的高质量创新产出。     

嗜热纤维素分解菌分离和筛选

从温泉、堆肥等环境采集样品,以滤纸条为唯一碳源,用微晶纤维素粉和羧甲基纤维素钠(CMC-Na)-刚果红培养基进行分离和筛选出几株高温纤维素分解菌.进行测定这些菌株的Cx、滤纸酶活性试验,两种酶的作用温度相对较宽,Cx酶的最适酶活性温度约70℃,而滤纸酶活性的最适温度因菌株差异有所差异.     

泡菜中乳酸菌的筛选及其生物学特性的研究

从泡菜中分离出4株具有乳酸菌菌落特征的菌株,菌株编号分别为L1、L2、L3和L4.经革兰氏染色,光学显微镜观察,生理试验等初步鉴定为乳酸菌.4株菌均为乳杆菌,其中菌株L4是较理想的纯种发酵菌株.     

Policy and evidence: a critical analysis of the Year 1 Phonics Screening Check in England

“This paper aims to present a critical analysis of the Year 1 Phonics Screening Check (PSC), with special focus on the relationship between the UK Department for Education's policy‐making and the evidence considered in the process of developing and evaluating the PSC. The reports from the in‐house Standards and Testing Agency and from commissioned external organisations with limited remits have been analysed, with emphasis on how the screening check findings have been used in DfE decision‐making. My conclusion is that the department has overestimated both the validity and the reliability of the check: partly because important sources of measurement error have not been explored, and partly because the available evidence has not been analysed in sufficient depth — or perhaps simply been ignored by the department. The whole phonics screening check seems to be the product of policy‐based evidence, rather than evidence‐based policy‐making. This has, in my view, seriously undermined the value of the PSC as a screening instrument, and one must wonder whether it is ‘fit for purpose’.     

排名前10的与预防运动和体育活动猝死相关的关键问题

参加有组织的体育运动和休闲活动存在发生严重伤病甚至死亡的内在风险。虽然造成体育运动或体育活动中猝死的原因有很多,但运动医学和循证标准治疗方面的进展已使临床医生得以更有效地预防、发现和治疗可能致死的伤患。随着研究与技术不断发展进步,当前的治疗标准正在不断发展以更好地改善患者的治疗效果。本文提出了10个与运动和体育活动中猝死的主要原因及其治疗手段有关的关键问题,未来开展的研究将提高运动员和休闲运动爱好者参与运动的安全度。当前证据表明,如采取正确的预防策略或最佳治疗方案,绝大多数的死亡案例是可以避免的。     

An easy-to-use site-directed mutagenesis method with a designed restriction site for convenient and reliable mutant screening

Site-directed mutagenesis (SDM) has been a very important method to probe the function-structure relationship of proteins. In this study, we introduced an easy-to-use, polymerase chain reaction (PCR)-based SDM method for double-stranded plasmid DNA, with a designed restriction site to ensure simple and efficient mutant screening. The DNA sequence to be mutated was first translated into amino acid sequence and then the amino acid sequence was reversely translated into DNA sequence with degenerate codons, resulting in a large number of sequences with silent mutations, which contained various restriction endonuclease (RE) sites. Certain mutated sequence with an appropriate RE site was selected as the target DNA sequence for designing a pair of mutation primers to amplify the full-length plasmid via inverse PCR. The amplified product was 5'-phosphorylated, circularized, and transformed into an Escherichia coli host. The transformants were screened by digesting with the designed RE. This protocol uses only one pair of primers and only one PCR is conducted, without the need for hybridization with hazardous isotope for mutant screening or subcloning step.     

科研成果在职称晋升中的信号与甄别作用研究

在学术水平不可验证的背景下,以科研成果的数量作为主要绩效依据的职称晋升能否有效分离不同学术水平的科学家并促进学术创新是学术评价制度有效性的一个重要体现。本文基于信息不对称理论的研究框架分析了科研成果的不可验证特征对职称晋升的影响。在此基础上,本文以1338名公共农业科研机构科学家为样本并利用信号理论和probit模型对职称晋升中科研成果的数量能否区分学术水平和学术创新努力不同的科学家进行了证实。理论分析与计量经济学研究结果表明:不可验证性使科研成果的学术水平不适合作为职称晋升的依据;在我国现行职称晋升制度下,科研成果的数量主要是科学家能否晋升职称的信号而非甄别其学术水平和学术创新性的有效方式。     

用西方教育经济理论浅析我国研究生教育改革的必要性

本文运用人力资本理论、筛选理论、劳动力市场划分理论,结合目前研究生教育中出现的主要问题及其原因,分析了研究生教育改革的必要性,并试图提出研究生教育的改革方向。     

论高等教育投资的信号成本与市场扭曲

随着20世纪90年代末我国高等教育的大规模扩招,高校各层次在校生人数急剧增加,国内人力资本过度投资的现象开始显现,而合适的社会就业岗位并没有相应快速增加,因而造成了日益严峻的就业问题。根据Spence的信号理论,教育对劳动生产率并没有增强的作用,而只能向雇主和社会发送信号以确定个体劳动者具备更高的生产能力或更好的可培训能力。在面临严峻就业问题时,高能力者就需要作进一步的教育投资,以发送文凭信号而被正确识别出来。这种为发送信号而进行追加教育投资的现象广泛存在,但并不能确保为个人带来更高收益,却会导致就业市场人力资源配置的扭曲,浪费国家稀缺的教育资源。     

军队院校合训学员实施全程淘汰制的探索与思考

军队院校正处于教育转型期,正在大力实施精英教育,培养大批的高素质新型军事人才。对此,军队院校应及时建立和实施学员全程淘汰制加以保证精英人才的培养。本文分析了实施学员全程淘汰制的重要意义,提出了军队院校合训学员全程淘汰制的构想和体系,并进行了试检验和可行性分析。