Chlorophyta species are common in the southern and northern coastal areas of China. In recent years, frequent green tide incidents in Chinese coastal waters have raised concerns and attracted the attention of scientis...Chlorophyta species are common in the southern and northern coastal areas of China. In recent years, frequent green tide incidents in Chinese coastal waters have raised concerns and attracted the attention of scientists. In this paper, we sequenced the 18S rDNA genes, the internal transcribed spacer （ITS） regions and the rbcL genes in seven organisms and obtained 536-566 bp long ITS sequences, 1 377-I 407 bp long rbcL sequences and 1 718-1 761 bp long partial 18S rDNA sequences. The GC base pair content was highest in the ITS regions and lowest in the rbcL genes. The sequencing results showed that the three Ulvaprolifera （or U. pertusa） gene sequences from Qingdao and Nan＇ao Island were identical. The ITS, 18S rDNA and rbcL genes in U. prolifera and U. pertusa from different sea areas in China were unchanged by geographic distance. U.flexuosa had the least evolutionary distance from U. californica in both the ITS regions （0.009） and the 18S rDNA （0.002）. These data verified that Ulva and Enteromorpha are not separate genera.展开更多
急性肾衰竭是一种发病率较高的临床疾病,尽早识别潜在患者有助于医生对其进行医疗干预,降低发病率和死亡率.近年来,依靠电子健康病历去预测患者潜在的健康风险逐渐受到关注.大多数模型通过聚合数据或者填充缺失值的方式处理人体生理指...急性肾衰竭是一种发病率较高的临床疾病,尽早识别潜在患者有助于医生对其进行医疗干预,降低发病率和死亡率.近年来,依靠电子健康病历去预测患者潜在的健康风险逐渐受到关注.大多数模型通过聚合数据或者填充缺失值的方式处理人体生理指标数据中存在的稀疏性和不规则性问题,忽视了缺失信息隐含的患者健康状态.此外,现有的急性肾衰竭预测模型并没有考虑各种模态的数据特点和模态之间的相关性.为了解决以上问题,提出了基于多模态的急性肾衰竭预测模型.该模型考虑了人体生理指标数据、疾病数据和人口统计学数据.设计了新的基于掩码和时间差的LSTM(long short term memory)网络去学习各个生理指标的时间间隔和缺失信息,捕获指标的数值变化和检测频率变化,引入了多头自注意力机制促进各模态表征的相互学习.在真实的数据集上进行了急性肾衰竭预测问题和死亡风险预测问题的实验,证明了所提出模型的有效性和合理性.展开更多
DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, par...DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, partly driven by the new sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species within the frame-work of the multi-species coalescent （MSC）. In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation （and their limitations） are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely what is being delimited and what assumptions we are making in doing so. Moreover, the methods can be very powerful when applied to large multi-locus datasets and thus take full advantage of data generated using today＇s technologies [Current Zoology 61 （5）： 846-853,2015].展开更多
基金Supported by the National Natural Science Foundation of China (No.30570125)the Key Construction Laboratory of Marine Biotechnology of Jiangsu Province (No. 2010HS03)
文摘Chlorophyta species are common in the southern and northern coastal areas of China. In recent years, frequent green tide incidents in Chinese coastal waters have raised concerns and attracted the attention of scientists. In this paper, we sequenced the 18S rDNA genes, the internal transcribed spacer （ITS） regions and the rbcL genes in seven organisms and obtained 536-566 bp long ITS sequences, 1 377-I 407 bp long rbcL sequences and 1 718-1 761 bp long partial 18S rDNA sequences. The GC base pair content was highest in the ITS regions and lowest in the rbcL genes. The sequencing results showed that the three Ulvaprolifera （or U. pertusa） gene sequences from Qingdao and Nan＇ao Island were identical. The ITS, 18S rDNA and rbcL genes in U. prolifera and U. pertusa from different sea areas in China were unchanged by geographic distance. U.flexuosa had the least evolutionary distance from U. californica in both the ITS regions （0.009） and the 18S rDNA （0.002）. These data verified that Ulva and Enteromorpha are not separate genera.
文摘急性肾衰竭是一种发病率较高的临床疾病,尽早识别潜在患者有助于医生对其进行医疗干预,降低发病率和死亡率.近年来,依靠电子健康病历去预测患者潜在的健康风险逐渐受到关注.大多数模型通过聚合数据或者填充缺失值的方式处理人体生理指标数据中存在的稀疏性和不规则性问题,忽视了缺失信息隐含的患者健康状态.此外,现有的急性肾衰竭预测模型并没有考虑各种模态的数据特点和模态之间的相关性.为了解决以上问题,提出了基于多模态的急性肾衰竭预测模型.该模型考虑了人体生理指标数据、疾病数据和人口统计学数据.设计了新的基于掩码和时间差的LSTM(long short term memory)网络去学习各个生理指标的时间间隔和缺失信息,捕获指标的数值变化和检测频率变化,引入了多头自注意力机制促进各模态表征的相互学习.在真实的数据集上进行了急性肾衰竭预测问题和死亡风险预测问题的实验,证明了所提出模型的有效性和合理性.
文摘DNA-based approaches to systematics have changed dramatically during the last two decades with the rise of DNA barcoding methods and newer multi-locus methods for species delimitation. During the last half-decade, partly driven by the new sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species within the frame-work of the multi-species coalescent （MSC）. In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation （and their limitations） are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely what is being delimited and what assumptions we are making in doing so. Moreover, the methods can be very powerful when applied to large multi-locus datasets and thus take full advantage of data generated using today＇s technologies [Current Zoology 61 （5）： 846-853,2015].
