1999–2021年,我国历经12次北极科学考察,获取了大量宝贵的极地海洋水文调查资料。历年以来的CTD调查设备为MARKⅢC CTD(第1、2次北极科学考察)和SBE911 Plus CTD(第3-12次北极科学考察),通过定点投放的方式获取海洋垂直断面的电导率、...1999–2021年,我国历经12次北极科学考察,获取了大量宝贵的极地海洋水文调查资料。历年以来的CTD调查设备为MARKⅢC CTD(第1、2次北极科学考察)和SBE911 Plus CTD(第3-12次北极科学考察),通过定点投放的方式获取海洋垂直断面的电导率、温度和深度数据,调查范围包含北极中央航道、楚科奇海、楚科奇海台、加拿大海盆、白令海峡、白令海、北欧海、北冰洋太平洋扇区等重点海域。通过数据格式转换、数据编辑、滤波和滞后处理、电导修正、起伏校正、衍生参数计算、生成等深间距文件、输出ASCII文件等过程对原始数据进行处理和质量控制,形成垂向分辨率为1 m,包含时间、经度、纬度、压强、深度、温度、盐度、密度、声速和位温等要素的数据集。通过比较同一变量两个传感器之间的数据差值和绘制T-S点聚图进一步评估处理后的数据质量。经评估,处理后的数据质量良好,剔除异常值后的双温盐传感器之间的差值在合理范围内。本数据集为北冰洋水团分布、环流研究、海洋环境变化及全球气候变化等提供了宝贵的现场资料。展开更多
船载温盐深剖面仪(Conductivity Temperature Depth profiler,CTD)的高精度温度传感器是获取海洋温度剖面数据的必备设备,每年仅进行一次校准不能保证传感器全年任何时刻的精度变化小于其初始值,且温度传感器在整个调查航次中是否能始...船载温盐深剖面仪(Conductivity Temperature Depth profiler,CTD)的高精度温度传感器是获取海洋温度剖面数据的必备设备,每年仅进行一次校准不能保证传感器全年任何时刻的精度变化小于其初始值,且温度传感器在整个调查航次中是否能始终保持初始精度存疑,因此发展现场温度传感器校准技术具有现实意义。本文围绕某航次中船载温度标准器海上试验过程,介绍了标准器的校准原理及固定点的工作方式,计算了固定点温坪拐点的相变温度,通过拟合方法得到了被校传感器校准系数。试验结果表明:传感器使用船载温度标准器校准后,温度误差的绝对值降低,数据整体更接近标准值,本文海试中的CTD剖面温度误差绝对值均值由校准前的30.2 mK缩小为23.2 mK。该船载温度标准器能够达到提高传感器测温准确性、减小测量误差的目的,为海洋调查现场温度传感器校准提供了一种新的思路。展开更多
Morpho-physiological evaluation of a crop’s genetic resources is necessary to find possible genotypes to include in breeding initiatives.The objective of this study was to identify heat-tolerant wheat genotypes among...Morpho-physiological evaluation of a crop’s genetic resources is necessary to find possible genotypes to include in breeding initiatives.The objective of this study was to identify heat-tolerant wheat genotypes among 36 mutant lines using morpho-physiological indices.Seedlings of mutant lines and check varieties were grown under both normal(control)and heat-stress conditions in growth chambers.Data were recorded on root-shoot parameters(length,fresh weight,dry weight,and ratio),relative water content(RWC),stability of cell membrane,pigment content,and chlorophyll fluorescence.Two-way analysis of variance showed significant(p<0.01,p<0.001)variation among 15 morpho-physiological features in both growing conditions.Correlation studies showed that pigment-specific indices(total chl,chl a,chl b,carotenoid,Fv/Fm—chlorophyll fluorescence)had significant positive correlations with rootshoot fresh weight(RFW,SFW)and root-shoot dry weight(RDW,SDW),and negative association with relative water content,stability of cell membrane at both conditions.Hierarchical cluster analysis revealed three primary clusters where cluster III(18 genotypes)showed minimal changes in studied characters than cluster I(11 genotypes)and cluster II(13 genotypes).Results obtained from this study revealed that the identified heat-sensitive(30-2 SSH)and heat-tolerant genotypes(27-2(4),29-2(2),and 30-2 SSH)of wheat might provide useful breeding materials for enhancing wheat yield even more in this period of uncertain climate change.展开更多
文摘1999–2021年,我国历经12次北极科学考察,获取了大量宝贵的极地海洋水文调查资料。历年以来的CTD调查设备为MARKⅢC CTD(第1、2次北极科学考察)和SBE911 Plus CTD(第3-12次北极科学考察),通过定点投放的方式获取海洋垂直断面的电导率、温度和深度数据,调查范围包含北极中央航道、楚科奇海、楚科奇海台、加拿大海盆、白令海峡、白令海、北欧海、北冰洋太平洋扇区等重点海域。通过数据格式转换、数据编辑、滤波和滞后处理、电导修正、起伏校正、衍生参数计算、生成等深间距文件、输出ASCII文件等过程对原始数据进行处理和质量控制,形成垂向分辨率为1 m,包含时间、经度、纬度、压强、深度、温度、盐度、密度、声速和位温等要素的数据集。通过比较同一变量两个传感器之间的数据差值和绘制T-S点聚图进一步评估处理后的数据质量。经评估,处理后的数据质量良好,剔除异常值后的双温盐传感器之间的差值在合理范围内。本数据集为北冰洋水团分布、环流研究、海洋环境变化及全球气候变化等提供了宝贵的现场资料。
文摘采用UHPLC-QE-Orbitrap MS技术结合网络分析和化学计量学建立钴胺素C(cblC)缺乏症的临床表型系统表征和预测模型,利用尝试解开其复杂性。基于UHPLC-QE-Orbitrap MS技术在正、负模式下采集的血液非靶向代谢组学图谱,利用数据驱动网络算法Connect the Dots(CTD)快速搜索高连通的扰动代谢物,化学计量学算法学习其组别间复杂微小变化模式。通过对两种临床表型(癫痫和代谢综合征)的研究,结果表明CTD算法识别出的扰动代谢物子集展示出高度的临床表型特异性,且涉及的富集通路扰动均被报道与癫痫和代谢综合征的致病机制密切相关。进一步,CTD算法能够量度高连通扰动代谢物间的协变信息,构建主要疾病模块系统地表征癫痫和代谢综合征的复杂致病机制。识别出的扰动代谢物作为特征变量集,采用5-折交叉验证,偏最小二乘判别分析、支持向量机和随机森林的受试者工作特征曲线下面积预测均值分别为0.849、0.897和0.909(癫痫),0.889、0.931和0.921(代谢综合征),马修斯相关系数预测均值分别为0.667、0.668和0.723(癫痫),0.686、0.696和0.787(代谢综合征)。上述结果表明了提出的计算方法在揭示cblC缺乏症的临床表型复杂性和指导其个性化诊断策略方面的有效性。
文摘Morpho-physiological evaluation of a crop’s genetic resources is necessary to find possible genotypes to include in breeding initiatives.The objective of this study was to identify heat-tolerant wheat genotypes among 36 mutant lines using morpho-physiological indices.Seedlings of mutant lines and check varieties were grown under both normal(control)and heat-stress conditions in growth chambers.Data were recorded on root-shoot parameters(length,fresh weight,dry weight,and ratio),relative water content(RWC),stability of cell membrane,pigment content,and chlorophyll fluorescence.Two-way analysis of variance showed significant(p<0.01,p<0.001)variation among 15 morpho-physiological features in both growing conditions.Correlation studies showed that pigment-specific indices(total chl,chl a,chl b,carotenoid,Fv/Fm—chlorophyll fluorescence)had significant positive correlations with rootshoot fresh weight(RFW,SFW)and root-shoot dry weight(RDW,SDW),and negative association with relative water content,stability of cell membrane at both conditions.Hierarchical cluster analysis revealed three primary clusters where cluster III(18 genotypes)showed minimal changes in studied characters than cluster I(11 genotypes)and cluster II(13 genotypes).Results obtained from this study revealed that the identified heat-sensitive(30-2 SSH)and heat-tolerant genotypes(27-2(4),29-2(2),and 30-2 SSH)of wheat might provide useful breeding materials for enhancing wheat yield even more in this period of uncertain climate change.
