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关键词： 橡皮布   绿色印刷材料   行业标准   国家新闻出版署   胶印   指标解析   有害物质   标识符  

摘要： 2020年11月,根据国家新闻出版署国新出发函[2020]249号《国家新闻出版署关于批准发布<文献片段标识符>等47项行业标准的通知》,行业标准CY/T 228-2020《绿色印刷材料胶印橡皮布》正式获得批准并自2021年2月1日起正式实施。CY/T 228-2020《绿色印刷材料胶印橡皮布》对符合绿色印刷材料要求的胶印橡皮布进行了界定,提出了具体的技术要求,特别是在第四章规定了胶印橡皮布中有害物质的限量。

关键词： amplicon sequence variant   chimeric amplicons   error correction   high‐   throughput amplicon sequencing   metabarcoding  

摘要： Sequencing and PCR errors are a major challenge when characterizing genetic diversity using high-throughput amplicon sequencing (HTAS). We have developed a multiplexed HTAS method, MAUI-seq, which uses unique molecular identifiers (UMIs) to improve error correction by exploiting variation among sequences associated with a single UMI. Erroneous sequences are recognized because, across the data set, they are over-represented among the minor sequences associated with UMIs. We show that two main advantages of this approach are efficient elimination of chimeric and other erroneous reads, outperforming dada2 and unoise3, and the ability to confidently recognize genuine alleles that are present at low abundance or resemble chimeras. The method provides sensitive and flexible profiling of diversity and is readily adaptable to most HTAS applications, including microbial 16S rRNA profiling and metabarcoding of environmental DNA.

关键词： COVID-19   Hospitalization   Mortality   Type 2 diabetes mellitus   Istanbul  

摘要： Aims: Type 2 diabetes mellitus (T2DM) is a risk factor for severe COVID-19. Our aim was to compare the clinical outcomes of patients with and without T2DM during the first hit of COVID-19 in Istanbul.& nbsp;Methods: A retrospective population-based study was conducted including all consecutive adult symptomatic COVID-19 cases. Patients were confirmed with rt-PCR;treated and monitored in accordance with standard protocols. The primary endpoints were hospitalization and 30-day mortality.& nbsp;Results: Of the 93,571 patients, 22.6% had T2DM, with older age and higher BMI. Propensity Score matched evaluation resulted in significantly higher rates of hospitalization (1.5-fold), 30-day mortality (1.6-fold), and pneumonia (1.4-fold). They revealed more severe laboratory deviations, comorbidities, and frequent drug usage than the Non-DM group. In T2DM age, pneumonia, hypertension, obesity, and insulin-based therapies were associated with an increased likelihood of hospitalization;whereas age, male gender, lymphopenia, obesity, and insulin treatment were considerably associated with higher odds of death.& nbsp;Conclusions: COVID-19 patients with T2DM had worse clinical outcomes with higher hospitalization and 30-day mortality rates than those without diabetes. Compared to most territories of the world, COVID-19 mortality was much lower in Istanbul, which may be associated with accessible healthcare provision and the younger structure of the population.& nbsp;(C)& nbsp;2021 Elsevier B.V. All rights reserved.

关键词： Nanopores  

摘要： Conformational changes of proteins play a vital role in implementing their functions and revealing the underlying mechanisms in various biological processes. It is still challenging to monitor protein conformations with temporal fingerprints of current-resistance pulses in the nanopore technique. Here the low-resolution morphologies of different conformations of a typical integrin, alpha(x)beta(2), were estimated via relative blockade currents simulated from all-atom molecular dynamics (MD). Distinct conformational states of alpha(x)beta(2) were directly explained by the volume and shape identifiers. Protein modulation in ionic current was analyzed from the conductivity distribution inside the protein-blocked nanopore. Combining a discrete model with spheroidal approximation, a MD-based approach was developed to theoretically predict the volume and shape of the nanopore for sensing alpha(x)beta(2). This method was also applicable in specifying morphological identifiers of six other proteins, and the theoretical predictions are in good agreement with the experimental measurements. These results potentiated the validity of this method for the conformational identification of proteins in nanopores.

关键词： 标注规则   数字对象   杂志内容   网络链接   网络传播权   知识产权   资源数字化   标识符  

摘要： 根据中华医学会杂志社有关通知要求,为更好的提升杂志内容资源数字化传播效能,保护数字资源在网络链接中的知识产权和网络传播权,实现对数字对象的持续追踪和阅读数据的有效统计,自2020年(第38卷)3期,我刊 DOI号标注规则进行修订。

关键词： 数字信息   条形码   网址   数字对象唯一标识符   互联网信息   唯一标识   有效的管理  

摘要： 数字对象唯一标识符(digital object identifitr,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号(ISBN、ISSN、ISCN)及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。

关键词： 分布式管理   DOI   条形码   数字信息   数字对象   物理地址   学术信息   识别码  

摘要： 数字对象唯一标识符(digital object identifier,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。在传统的出版物中,书刊、磁带、光盘都有国际标准编号(ISBN、ISSN、ISCN)及其条形码,作为出版物的唯一标识。这些标识使出版物得到有效的管理,便于读者查找和利用。而网上的文档一旦变更了网址便无从追索。数字信息标注DOI如同出版物的条形码,是一个永久和唯一的标识号。随着时间推移,数字对象的某些有关信息可能会有变化(包括存储的物理位置),而DOI可让使用者直接由此链接到出版商的数据库、文献、摘要甚至是全文,识别码可以直接指引到出版物的本身,使国内外各种来源、不同物理地址的各种类型的学术信息实现互链互通。DOI是一个可供全球期刊快速链接的管理系统,整个系统由国际DOI基金会(IDF)进行全球分布式管理。

关键词： 数字对象标识符   数字化期刊   数字化传播   杂志内容   DOI   网络链接   数字信息   网络传播权  

摘要： 数字对象标识符(digital object identifier,DOI)是对包括互联网信息在内的数字信息进行标识的一种工具。为了实现杂志内容资源的有效数字化传播,同时保护这些数字资源在网络链接中的知识产权和网络传播权,为标识对象的版权状态提供基础,实现对数字对象版权状态的持续追踪,本杂志纸版期刊和数字化期刊的论文全部标注DOI。即除科普和消息类稿件外,其他文章均需标DOI。由编辑部为决定刊载的论文标注DOI。

关键词： Unique molecular identifiers   Molecular barcodes   Probabilistic genotyping   Stutter  

摘要： Unique molecular identifiers (UMIs) are a promising approach to contend with errors generated during PCR and massively parallel sequencing (MPS). With UMI technology, random molecular barcodes are ligated to template DNA molecules prior to PCR, allowing PCR and sequencing error to be tracked and corrected bioinformatically. UMIs have the potential to be particularly informative for the interpretation of short tandem repeats (STRs). Traditional MPS approaches may simply lead to the observation of alleles that are consistent with the hypotheses of stutter, while with UMIs stutter products bioinformatically may be re-associated with their parental alleles and subsequently removed. Herein, a bioinformatics pipeline named strumi is described that is designed for the analysis of STRs that are tagged with UMIs. Unlike other tools, strumi is an alignment-free machine learning driven algorithm that clusters individual MPS reads into UMI families, infers consensus super-reads that represent each family and provides an estimate the resulting haplotype's accuracy. Super-reads, in turn, approximate independent measurements not of the PCR products, but of the original template molecules, both in terms of quantity and sequence identity. Provisional assessments show that naive threshold-based approaches generate super-reads that are accurate (similar to 97 % haplotype accuracy, compared to similar to 78 % when UMIs are not used), and the application of a more nuanced machine learning approach increases the accuracy to similar to 99.5 % depending on the level of certainty desired. With these features, UMIs may greatly simplify probabilistic genotyping systems and reduce uncertainty. However, the ability to interpret alleles at trace levels also permits the interpretation, characterization and quantification of contamination as well as somatic variation (including somatic stutter), which may present newfound challenges.

关键词： Digital image correlation   Optical microscopy   Residual intensity   Magnesium   Twinning  

摘要： Background In the microscopic observation of deforming metals, it is well known that crystallite defects that accommodate strain can occasionally become visible, namely, they introduce image contrast to their locality. For microscopic digital image correlation (DIC) applications, this is typically known as a disturbance. Objective Here, we explore a potential upside of these image-intensity offsets, to present a new mode of differential imaging that exclusively displays the underlying plasticity agents. Methods For this, the intensity-offset signal is isolated with residual intensity, essentially the differential between reference- and deformed-configuration intensity of each material point. The premise is showcased over an autocatalytic twin band in Magnesium AZ31, with an advanced DIC instrument that utilizes bright-field optical microscopy. With robust area-scanning that utilizes in-situ corrective measures, a material field of around 5000 grains (13 mu m average size) is sampled with a maximal intragranular resolution (similar to 250 data points per grain) for this technique. For added robustness against the intensity alterations, a DIC algorithm (Augmented Lagrangian DIC) that enforces global kinematic compatibility constraints is utilized. Results The calculated residual intensity map yields a detailed image of the twin networks that show a strong positional alignment with the strain localizations. At the band boundary, the twins (and their accompanying strain localization) protrude into the dormant material in a comb-like pattern. Conclusions With a combination of high-resolution optics and defects that alter the surface topography, residual intensity presents a new in-situ microscopy mode that is tied to the DIC analysis. This principle also offers potential micro-deformation imaging capabilities for various other material-microscopy combinations.