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关键词： COMMUNITIES   SIGNATURES  

摘要： Motivation Learning associations of traits with the microbial composition of a set of samples is a fundamental goal in microbiome studies. Recently, machine learning methods have been explored for this goal, with some promise. However, in comparison to other fields, microbiome data are high-dimensional and not abundant; leading to a high-dimensional low-sample-size under-determined system. Moreover, microbiome data are often unbalanced and biased. Given such training data, machine learning methods often fail to perform a classification task with sufficient accuracy. Lack of signal is especially problematic when classes are represented in an unbalanced way in the training data; with some classes under-represented. The presence of inter-correlations among subsets of observations further compounds these issues. As a result, machine learning methods have had only limited success in predicting many traits from microbiome. Data augmentation consists of building synthetic samples and adding them to the training data and is a technique that has proved helpful for many machine learning tasks. Results In this paper, we propose a new data augmentation technique for classifying phenotypes based on the microbiome. Our algorithm, called TADA, uses available data and a statistical generative model to create new samples augmenting existing ones, addressing issues of low-sample-size. In generating new samples, TADA takes into account phylogenetic relationships between microbial species. On two real datasets, we show that adding these synthetic samples to the training set improves the accuracy of downstream classification, especially when the training data have an unbalanced representation of classes. Availability and implementation TADA is available at https://***/tada-alg/TADA. Supplementary information Supplementary data are available at Bioinformatics online.

关键词： ELLENBERG INDICATOR VALUES   DNA   BIODIVERSITY   TOOL  

摘要： Environmental DNA (eDNA) is increasingly applied in ecological studies, including studies with the primary purpose of criminal investigation, in which eDNA from soil can be used to pair samples or reveal sample provenance. We collected soil eDNA samples as part of a large national biodiversity research project across 130 sites in Denmark. We investigated the potential for soil eDNA metabarcoding in predicting provenance in terms of environmental conditions, habitat type and geographic regions. We used linear regression for predicting environmental gradients of light, soil moisture, pH and nutrient status (represented by Ellenberg Indicator Values, EIVs) and Quadratic Discriminant Analysis (QDA) to predict habitat type and geographic region. eDNA data performed relatively well as a predictor of environmental gradients (R-2 > 0.81). Its ability to discriminate between habitat types was variable, with high accuracy for certain forest types and low accuracy for heathland, which was poorly predicted. Geographic region was also less accurately predicted by eDNA. We demonstrated the application of provenance prediction in forensic science by evaluating and discussing two mock crime scenes. Here, we listed the plant species from annotated sequences, which can further aid in identifying the likely habitat or, in case of rare species, a geographic region. Predictions of environmental gradients and habitat types together give an overall accurate description of a crime scene, but care should be taken when interpreting annotated sequences, e.g. due to erroneous assignments in GenBank. Our approach demonstrates that important habitat properties can be derived from soil eDNA, and exemplifies a range of potential applications of eDNA in forensic ecology.

关键词： PPP   “一带一路”   基础设施   私人成本  

摘要： “一带一路”沿线的发展中国家自20世纪末开始广泛采用PPP模式建设基础设施。分析过去近三十年的PPP模式对基础设施效率的促进作用,不仅是对沿线国家过去PPP模式效果的检验,同时对未来“一带一路”建设中PPP模式的应用也具有指导意义。本文首先对沿线43个发展中国家2000-2016年ICT基础设施效率水平进行测算,然后采用Tobit模型对PPP项目数量对ICT基础设施效率的促进作用进行实证检验。结果表明,沿线国家PPP投资额与基础设施效率显著正相关,将基础设施效率进行Malmquist指数分解后发现,私人资本参与基础设施建设和运营对基础设施效率和社会福利改善具有更强相关性。同时由于私人资本的参与更多的是带来规模效应,通过新建基础设施促进贸易和生产要素流动进而提升基础设施效率和社会福利水平,说明在未来“一带一路”建设中,私人部门参与基础设施建设仍有广阔提升空间。

关键词： 化学试剂分类   食品药品检验机构   化学试剂管理   作用研究  

摘要： 本文分析了危险品化学试剂与非危险品化学试剂的分类方式,对其提出了不同的贮藏方式,并分析了对化学试剂进行分类的重要意义,便于化学试剂的选购,优化化学试剂的分类储藏和保管,促进化学试剂的正确配制与使用,方便废弃化学试剂分类销毁,对化学试剂的正确使用创造了有效条件。

关键词： 检验科   临床沟通   住培医师   沟通模式  

摘要： 检验医学在很大程度上推动着临床医学的发展,医院的检验科与临床科室相得益彰,相辅相成密不可分。通过结合该院检验科的沟通实践,介绍检验科与临床科室之间的沟通措施及认识体会、实施效果,旨在探讨检验科与临床科室之间的沟通模式,如何有效地发挥检验科住培医师的作用,对当前较薄弱而需亟待加强的该方面工作提供一定的参考。

关键词： 氧化性固体   物理形态   包衣处理   O.3   试验方法  

摘要： 为了研究物理形态及包衣处理对氧化性固体氧化性质的影响,选择颗粒状过碳酸钠作为氧化性固体待测物质,在此基础上进行0.5 mm 过筛和研磨处理。根据联合国《关于危险货物运输的建议书试验和标准手册》中O.3:氧化性固体的试验方法测试燃烧速率。通过实验结果可以得出样品的氧化性为:过碳酸钠<过碳酸钠(<0.5 mm)<过碳酸钠(粉末)。通过比较包衣/未包衣的实验结果可以证明包衣处理对氧化性固体氧化性质起到明显的减缓作用。建议对氧化性固体的形态和情况更加全面和精确的描述,确保氧化性固体分类判定的准确性。

关键词： 上海市包装技术协会   回收利用   垃圾分类   回收再利用   管理条例   生活垃圾   专家学者   企业代表  

摘要： 为切实施行《上海市生活垃圾管理条例》,认真做好垃圾源头减量、包装物减量和回收利用工作,上海市包装技术协会于2019年6月11日下午召开“垃圾分类包装减量回收利用”圆桌会议。会议邀请政府有关部门领导,组织各方面的专家学者、有关行业的企业代表三十余人共同探讨研究包装源头减量、末端回收再利用问题。会上,费钧德会长首先作了致词。

关键词： 卡式微柱凝胶技术   血型鉴定   红细胞不规则抗体检验  

摘要： 目的探讨卡式微柱凝胶技术在ABO和RhD血型鉴定及输血前红细胞不规则抗体检验中的作用。方法选择2015年1月~2018年1月本院接收的行卡式微柱凝胶技术和试管法法鉴定的6500例输血患者作为研究对象,均行ABO和RhD血型鉴定、输血前红细胞不规则抗体检验等,观察两种方法检测结果。结果卡式微柱凝胶技术ABO和RhD血型鉴定一次准确率分别为99.72%、99.83%,均显著高于试管法98.78%、99.57%,P<0.05;卡式微柱凝胶技术不规则抗体检出率1.05%,试管法不规则抗体检出率0.54%,差异显著,P<0.05;两种方法共检出113例不规则抗体阳性患者,其中血液科36例、肾病科30例、感染科31例、其他科室16例;其中输血史98例。结论在ABO和RhD血型鉴定及输血前红细胞不规则抗体检验中采用卡式微柱凝胶技术具有较高的价值,操作简单且准确率高,确保预防溶血性输血不良反应的发生,保证输血安全,检验价值较高。

关键词： 微生物检验   感染性疾病   预防   诊疗  

摘要： 目的对于感染性疾病而言,解析微生物检验方式应用后的预防和诊疗效果。方法选取2018年9月至2019年5月新疆伊犁州疾病预防控制中心实收治的110例患者为研究对象,依据平均分组方式分成实验组和参照组,各55例。参照组患者实施常规检验,实验组患者实施微生物检验方法,分析两组患者的临床数据。结果实验组中患者的重度与中度感染数据显著比参照组的数据低;而轻度感染数据则是实验组高于参照组数据(P<0.05)。实验组总有效率94.55%,高于参照组的72.73%(P<0.05)。结论对感染性疾病实施微生物检查,其能够做到有效预防,并且提升临床诊断准确率。