现代田径运动训练的主要特征——兼论我国田径训练中存在的问题和对策

为了提高我国田径训练水平。通过综述方法揭示我国田径训练的主要特征、训练存在问题和对策。结果表明现代田径运动训练具有专项化、强度大、技术训练与素质训练紧密结合、突出心理训练的实效性、围绕比赛缩短训练周期等主要特征。我国田径运动训练中存在综合化水平低、基础理论薄弱以及后备人才培养脱节等问题 ,必须通过提高教练员理论水平与工作能力 ,加大科学化训练力度 ,理顺各层次人才培养的关系等途径加以解决。     

田野调查:人类学方法在图书馆学中的应用

田野调查是人类学标志性的科学方法,与文献研究、问卷调查、科学实验、案例分析等方法相比有着自身的特点。田野调查法的原则、技术可以移植到图书馆学研究之中,适用于研究图书馆事业的边缘地带,从多方面说明研究对象,展示原生事物存在的合理性及其寓意。现有图书馆学的田野调查实践,也证实了人类学方法与图书馆学交叉是有效的。图书馆学借鉴人类学田野调查方法,有助于丰富自身方法论内容,也有助于提升图书馆学跨学科研究的能力。参考文献31。     

The use of the Percentage Rank Position index for comparative evaluation of journals

In the present paper the Percentage Rank Position (PRP) index concluding from the principle of Similar Distribution of Information Impact in different fields of science (Vinkler, 2013), is suggested to assess journals in different research fields comparatively. The publications in the journals dedicated to a field are ranked by citation frequency, and the PRP-index of the papers in the elite set of the field is calculated. The PRP-index relates the citation rank number of the paper to the total number of papers in the corresponding set. The sum of the PRP-index of the elite papers in a journal, PRP(j,F) may represent the eminence of the journal in the field. The non-parametric and non-dimensional PRP(j,F) index of journals is believed to be comparable across fields.     

The correlation between citation-based and expert-based assessments of publication channels: SNIP and SJR vs. Norwegian quality assessments

We study the correlation between citation-based and expert-based assessments of journals and series, which we collectively refer to as sources. The source normalized impact per paper (SNIP), the Scimago Journal Rank 2 (SJR2) and the raw impact per paper (RIP) indicators are used to assess sources based on their citations, while the Norwegian model is used to obtain expert-based source assessments. We first analyze – within different subject area categories and across such categories – the degree to which RIP, SNIP and SJR2 values correlate with the quality levels in the Norwegian model. We find that sources at higher quality levels on average have substantially higher RIP, SNIP, and SJR2 values. Regarding subject area categories, SNIP seems to perform substantially better than SJR2 from the field normalization point of view. We then compare the ability of RIP, SNIP and SJR2 to predict whether a source is classified at the highest quality level in the Norwegian model or not. SNIP and SJR2 turn out to give more accurate predictions than RIP, which provides evidence that normalizing for differences in citation practices between scientific fields indeed improves the accuracy of citation indicators.     

高职计算机应用技术专业现状分析

计算机应用技术专业是综合性高职院校中都有的专业,是一个高考报考“热门”专业,这几年,却因学生的就业稳定率低而被列入虹牌预警专业。本文针对这种现象,对计算机应用技术专业进行了深入的剖析,找出了该专业的问题所在,同时提出了专业改革的方向和方法。     

水稻穗内不同粒位间的矿质营养变化差异及其与籽粒植酸含量的关系

研究目的：阐明水稻穗内不同粒位间的主要矿质营养元素和植酸含量差异、粒位分布特点及其与品种穗型间的联系。 创新要点：将水稻品种的穗型变化与稻米营养品质结合起来,从水稻穗粒结构角度,对同一稻穗内不同籽粒间的主要矿质营养元素与植酸含量差异、粒位分布特点及其与水稻品种穗型间的相互关系进行了较系统的探讨分析。 研究方法：以典型的直立穗型和弯穗型粳稻品种为材料,通过对两类水稻品种在相同栽培条件下籽粒矿质营养元素和植酸含量的测定分析,并依据水稻籽粒在稻穗上的着生部位,将同一稻穗内的不同籽粒划分为六个粒位,比较分析了两类品种同一稻穗内不同部位间矿质营养元素和植酸含量的差异变化及其粒位分布特点。 重要结论：水稻穗型虽然与品种问的籽粒矿质营养元素和植酸含量高低没有直接关系,但对其穗内不同籽粒间的主要矿质营养元素和植酸含量存在着较大影响;与稻穗中下部的弱势粒相比,同一稻穗内着生在稻穗上中部的强势粒通常具有相对较高的锌、铁矿质元素含量,而籽粒植酸含量和植酸,锌（铁）摩尔比则有所降低,稻米营养品质也相对较好;不同矿质营养元素相比,粒位效应对铁矿质营养的影响作用要略大于对钙和锌营养元素含量。     

植物学野外实习教学改革之我见

为了在较短时间内取得理想的植物学野外实习效果,进一步提高野外实习的教学质量和水平。文章从实习指导教师的组织、学生的组织和管理、教学方法、实习考核方式这四个方面,提出针对植物学野外实习的教学改革新见解。     

一种基于卷积神经网络和双向长短记忆神经网络的在线医疗社区问答文本实体识别方法

[目的/意义]针对在线医疗社区问答文本复杂程度高、结构化程度低的特点,结合卷积神经网络（CNN）和双向长短记忆神经网络（BiLSTM）两种深度学习模型以及条件随机场（CRF）模型,提出一套适用于在线医疗问答文本的实体识别方法并进行验证。 [过程/方法] 将问答文本进行清洗和BIO标注后,分别用CNN和BiLSTM进行字级别的特征抽取,将两种模型抽取到的特征进行融合,后放入CRF中训练出实体预测模型,再将问答文本放入训练好的模型中得到最终的实体识别结果。[结果/结论]在所选取的乳腺癌医疗社区问答文本数据集上,所提出的方法结果优于其他模型,且识别准确率达到92.3%,召回率达到89.3%,F值达到90.8%。     

Identification and characterization of profilin gene family in rice

BackgroundProfilin proteins (PRFs) are small (12–15 kD) actin-binding protein, which play a significant role in cytoskeleton dynamics and plant development via regulating actin polymerization. Profilins have been well documented in Arabidopsis, Zea mays L. as well as Phaseolus vulgaris, however no such fully characterization of rice (Oryza sativa L.) profilin gene family has been reported thus far.ResultIn the present study, a comprehensive genome-wide analysis of rice PRF genes was completed and three members were identified. OsPRF1 and OsPRF2 shared 98.5% similarity (6 nucleotide divergence), but the deduced amino acid sequences of OsPRF1 and OsPRF2 are fully identical. In contrast, the OsPRF3 presents relatively lower similarity with OsPRF1 and OsPRF2. Phylogenetic analysis also support that OsPRF1 has a closer relationship with OsPRF2. Expression pattern analysis revealed the differential expression of OsPRFs in tissues of mature plant, which suggested the potential spatial functional specificity for rice profilin genes. Subcellular localization analysis revealed the OsPRFs were localized in cytoplasm and nucleus and all of them could bind actin monomers. Furthermore, abiotic stresses and hormones treatments assay indicated that the three OsPRF genes could be differentially regulated, suggesting that OsPRF genes might participate in different stress processes in rice.ConclusionsTaken together, our study provides a comprehensive analysis of the OsPRF gene family and will provide a basis for further studies on their roles in rice development and in response to abiotic stresses.How to cite: Zhang Y, Dong G, Wu L, et al. Identification and characterization of profilin gene family in rice. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.08.004.     

Preferred field of study and academic performance

This paper investigates the impact of studying the first-choice university subject on dropout and switching field of study for a cohort of students in Germany. Using detailed survey data, and employing an instrumental variable strategy based on variation in the local field of study availability, we provide evidence that students who are not enrolled in their preferred field of study are more likely to change their field, delay graduation and drop out of university. The estimated impact on dropout is particularly strong among students of low socio-economic status and is likely to be driven by lower effort and motivation.