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81.
Jia-Qi Gu Hui Zhao Xiao-Yuan Guo Hao-Yun Sun Jing-Yi Xu Yi-Liang Wei 《Electrophoresis》2022,43(11):1183-1192
Population stratification analyses targeting genetically closely related East Asians have revealed that distinguishable differentiation exists between Han Chinese, Korean, and Japanese individuals, as well as between southern (S-) and northern (N-) Han Chinese. Previous studies offer a number of choices for ancestry informative single nucleotide polymorphisms (AISNPs) to discriminate East-Asian populations. In this study, we collected and examined the efficiency of 1185 AISNPs using frequency and genotype data from various publicly available databases. With the aim to perform fine-scale classification of S-Han, N-Han, Korean, and Japanese subjects, machine-learning methods (Softmax and Random Forest) were used to screen a panel of highly informative AISNPs and to develop a superior classification model. Stepwise classification was implemented to increase and balance the discrimination in the process of AISNP selection, first discriminating Han, Korean, and Japanese individuals, and then characterizing stratification between S-Han and N-Han. The final 272-AISNP panel is an alternative optimization of various previous works, which promises reliable and >90% accuracy in classification of the four East-Asian groups. This AISNP panel and the machine-learning model could be a useful and superior choice in medical genome-wide association studies and in forensic investigations for unknown suspect identity. 相似文献
82.
Kuang Jia-Qi Zhuang Jia-Qing Zhou Jing Wang Xiao-Ling Ou Guang-Chuan 《Transition Metal Chemistry》2019,44(3):263-268
Transition Metal Chemistry - The reactions of transition metal macrocyclic complexes [ML](ClO4)2 (L?=?1,8-diethyl-1,3,6,8,10,13-hexaazacyclotetradecane, M=Ni, Cu) with NH4VO3 gave two... 相似文献
83.
In this paper, a class of coupled system for the El Nin o/La Nin a southern oscillation (ENSO) atmospheric physics oscillation model is considered. We propose an ENSO atmospheric physics model using a method from the asymptotic theory. It is indicated from the results that the asymptotic method can be used for analyzing the sea surface temperature anomaly and the thermocline depth anomaly of the atmosphere-ocean oscillation for the ENSO model in the equatorial Pacific. 相似文献
84.
水下黏合剂在生物医学和工程应用领域的需求越来越大。然而,目前报道的大多数水下黏合剂的制备方法中通常需要复杂的化学偶联或修饰,以及昂贵的构筑基元。本文利用低成本的葡萄籽提取物原花青素(PA)和商业化的聚乙二醇寡聚物(PEG)为构筑基元,发展了一种简单且经济的水下黏合剂的构筑策略,实现了在氢键作用下诱导仿生黏合剂生成。此黏合剂既可以在水上又可以在水下黏附不同材质的基底,且可重复使用。此外,易于制备的PA/PEG黏合剂也具有良好的抗菌活性和生物相容性。由于PA/PEG黏合剂具有制备简单、广谱黏附性、可循环使用和抗菌性等优点,将在医疗器械和制药应用中得到广泛应用。 相似文献
86.
以晶体结构教学为例,引导学生利用VESTA软件搭建典型晶体的晶胞模型可大大激发学习兴趣,降低认知难度。通过金刚石、金属镁、金属铜、氯化钠、萤石等晶胞模型的搭建,空间充填模型的旋转与观察,晶面及配位多面体的插入,帮助学生突破原子分数坐标、空间利用率计算、晶体空隙的洞察等难点,是VESTA支撑下的具体教学策略。学生在体验真实建模的过程中加深了对认识原型的理解,收获了知识与快乐,发展了证据推理与模型认知这一化学学科核心素养。 相似文献
87.
Zhao MQ Zhang Q Zhang W Huang JQ Zhang Y Su DS Wei F 《Journal of the American Chemical Society》2010,132(42):14739-14741
A chemical precursor mediated process was used to form catalyst nanoparticles (NPs) with an extremely high density (10(14) to 10(16) m(-2)), controllable size distribution (3-20 nm), and good thermal stability at high temperature (900 °C). This used metal cations deposited in layered double hydroxides (LDHs) to give metal catalyst NPs by reduction. The key was that the LDHs had their intercalated anions selected and exchanged by guest-host chemistry to prevent sintering of the metal NPs, and there was minimal sintering even at 900 °C. Metal NPs on MoO(4)(2-) intercalated Fe/Mg/Al LDH flakes were successfully used as the catalyst for the double helix growth of single-walled carbon nanotube arrays. The process provides a general method to fabricate thermally stable metal NPs catalysts with the desired size and density for catalysis and materials science. 相似文献
88.
Reverse Binding Ability of Four Calix[ 4 ] crowns in Gas and Acetonitrile towards Butylamine Isomers
ZHANG Guo-Zhu LI Yuan-Yuan WANG Min LIU Yan-Fei HE Jia-Qi HE Xi-Wen CHENG Jin-Pei 《有机化学》2003,23(Z1):186-187
Synthetic host molecules having neutral organic cavities capable of accommodating bio significant moleculars are of great interest in supramolecular chemistry these days.[1] Calixarenes, as the third generation of the host supramolecules after crown ether and cyclodextrin, can serve as good "flatform" to design versatile selective recep- tors for ionic and neutral molecules. [2] 相似文献
89.
90.