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Improved mammalian family phylogeny using gap-rare multiple sequence alignment:A timetree of extant placentals and marsupials

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Zoological Research 2023年第6期44卷 1064-1079页

作者： Gao-Ming liu Qi Pan Juan Du Ping-Fen Zhu Wei-Qiang liu Zi-Hao li ling Wang Chun-Yan Hu Yi-Chen Dai Xiao-Xiao Zhang Zhan Zhang Yang Yu Meng li Peng-Cheng Wang Xiao Wang Ming li Xu-Ming Zhou Key Laboratory of Animal ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China School of life Sciences University of Science and Technology of ChinaHefeiAnhui 230026China College of life Sciences Nanjing Normal UniversityNanjingJiangsu 210023China

The timing of mammalian diversification in relation to the Cretaceous-Paleogene(KPg)mass extinction continues to be a subject of substantial *** studies have either focused on limited taxonomic samples with available whole-genome data or relied on short sequence alignments coupled with extensive species *** the present study,we improved an existing dataset from the landmark study of Meredith et al.(2011)by filling in missing fragments and further generated another dataset containing 120 taxa and 98 exonic *** these two datasets,we then constructed phylogenies for extant mammalian families,providing improved resolution of many conflicting ***,the timetrees generated,which were calibrated using appropriate molecular clock models and multiple fossil records,indicated that the interordinal diversification of placental mammals initiated before the Late Cretaceous ***,intraordinal diversification of both extant placental and marsupial lineages accelerated after the KPg boundary,supporting the hypothesis that the availability of numerous vacant ecological niches subsequent to the mass extinction event facilitated rapid ***,our results support a scenario of placental radiation characterized by both basal cladogenesis and active interordinal divergences spanning from the Late Cretaceous into the Paleogene.

关键词： Mammals Phylogeny Diversification evolutionary model

钙磷生物陶瓷支架的常温自强式3D打印技术与工艺研究

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陕西科技大学学报 2025年第1期43卷 126-135页

作者：贾倩倩赵雪妮袁海泉李玲娜石国文朱智鹏刘朝阳谷泽鑫陕西科技大学机电工程学院陕西西安710021

在常温不添加高分子聚合物粘接剂的情况下,首次研发了自强式钙磷生物陶瓷的无需高温后处理的3D打印成型技术与工艺.通过材料表征、孔隙率、力学性能测试和降解性测试对不同配比和不同打印间距的支架进行研究.结果表明,随着HA含量从70 w... 详细信息

在常温不添加高分子聚合物粘接剂的情况下,首次研发了自强式钙磷生物陶瓷的无需高温后处理的3D打印成型技术与工艺.通过材料表征、孔隙率、力学性能测试和降解性测试对不同配比和不同打印间距的支架进行研究.结果表明,随着HA含量从70 wt.%减小至50 wt.%,浆料粘度与打印成型性变差,孔隙尺寸减小,而60 wt.%HA含量浆料具有良好的打印成型性,所打印的支架结构稳定、均匀.压缩强度随着HA含量的减少而增大,60 wt.%和50 wt.%含量的HA打印的钙磷生物陶瓷支架压缩强度分别为3.61±0.194 MPa(0.6-HTC)和5.28±0.629 MPa(0.5-HTC),能够匹配松质骨的要求.此外,随着打印间距(1 mm、2 mm和4 mm)的增加,支架的压缩强度也随之降低.随着HA含量的增加,钙磷生物陶瓷支架的孔隙率先增大后减小.60 wt.%HA含量的支架孔隙率最大(51.4%),降解性能优异,且降解后能保持完整性.此创新的3D打印技术能够根据临床手术现场患者实际植入部位结构尺寸要求直接打印并调整支架结构和形状,具有极大的应用前景.

关键词： 3D打印钙磷生物陶瓷支架力学性能生物降解性

Nuclear assembly of purified Crythecodinium cohnii chromosomes in cell-free extracts of Xenopus laevis eggs

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Cell Research 2000年第2期10卷 127-137页

作者： liU XIAO ling YAN SHeN eR JIe CHeN ZHONG HeZHAI(e-mail: zhaizh@*** Tel: 86-10-62754293 Fax: 86-10-62751526)(College of life Sciences, Peking University, Beijing 100871,China) College of life Sciences Peking University Beijing China

Incubation of dinoflagellate Crythecodinium cohnii chromosomes in cytoplasmic extracts of unfertilized Xenopus laevis eggs resulted in chromosomes decondensation and recondensation, nuclear envelope assembly, and nuclear *** Crythecodinium cohnii is a kind of primitive eukaryote which possesses numerous permanently condensed chromosomes and discontinuous double-layered nuclear membrane throughout the cell cycle. The assembled nuclei, being surrounded by a continuous double membrane containing nuclear pores and the uniformly dispersed chromatin fibers are morphologically distinguishable from that of Dinoflagellate Crythecodinium cohnii. However, incubation of dinoflagellate Crythecodinium cohnii chromosomes in the extracts from dinoflagellate Crythecodinillm cohnii cells does not induce nuclear reconstitution.

关键词： Dinoflagellate Crythecodinium cohnii chromosome nuclear reconstitution cell-free system Xenopus laevis egg extracts

太阳能中温利用相变材料MgCl_2·6H_2O的热循环耐久性研究

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功能材料 2014年第9期45卷 127-131页

作者：李文浩徐玲玲南京工业大学材料科学与工程学院南京210009 南京工业大学江苏省过程强化与新能源装备技术重点实验室南京210009

分别在密封和未密封条件下对六水合氯化镁(MgCl2·6H2O)进行600次加速热循环实验,研究其作为太阳能中温蓄热材料的可行性。采用差示扫描量热仪、X射线衍射仪和多路温度测试仪测试不同次数热循环后样品的相变温度、相变潜热、晶体结构和... 详细信息

分别在密封和未密封条件下对六水合氯化镁(MgCl2·6H2O)进行600次加速热循环实验,研究其作为太阳能中温蓄热材料的可行性。采用差示扫描量热仪、X射线衍射仪和多路温度测试仪测试不同次数热循环后样品的相变温度、相变潜热、晶体结构和过冷度。结果表明,未密封状态下,200次热循环后,MgCl2·6H2O的相变潜热降低54.2%,并有新相MgCl2·4H2O产生;密封状态下,600次热循环后,MgCl2·6H2O的相变温度和峰值温度的变化分别在±1%和±4%内,相变潜热的变化在-15.2%^+1.5%内(300次热循环后变化异常);同时,MgCl2·6H2O凝固时几乎没有过冷现象,过冷度在0~2.2℃之间。密封状态下,MgCl2·6H2O在太阳能中温蓄热应用中是一种很有发展前景的材料。

关键词：六水合氯化镁加速热循环相变温度相变潜热差式扫描量热法(DSC)

Species-level Microbiota of Biting Midges and Ticks from Poyang Lake

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Biomedical and environmental Sciences 2024年第3期37卷 266-277,I0001-I0003页

作者： GONG Jian WANG Fei Fei liU Yang Qing PU Ji DONG ling Zhi ZHANG Si Hui HUANG Zhen Zhou HUANG Yu Yuan li Ya Ben YANG Cai Xin TAO Yuan Meihui ZHAO li Jun JIN Dong liU li Yun YANG Jing LU Shan Department of epidemiology School of Public HealthShanxi Medical UniversityTaiyuan 030001ShanxiChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Jiangxi Provincial Key Laboratory of Animal-Origin and Vector-Borne Diseases Nanchang Center for Disease Control and PreventionNanchang 330038JiangxiChina Research Units of Discovery of Unknown Bacteria and Function Chinese Academy of Medical SciencesBeijing 100730China

Objective The purpose of this study was to investigate the bacterial communities of biting midges and ticks collected from three sites in the Poyang Lake area,namely,Qunlu Practice Base,Peach Blossom Garden,and Huangtong Animal Husbandry,and whether vectors carry any bacterial pathogens that may cause diseases to humans,to provide scientific basis for prospective pathogen discovery and disease prevention and *** Using a metataxonomics approach in concert with full-length 16S rRNA gene sequencing and operational phylogenetic unit(OPU)analysis,we characterized the species-level microbial community structure of two important vector species,biting midges and ticks,including 33 arthropod samples comprising 3,885 individuals,collected around Poyang *** A total of 662 OPUs were classified in biting midges,including 195 known species and 373 potentially new species,and 618 OPUs were classified in ticks,including 217 known species and 326 potentially new ***,OPUs with potentially pathogenicity were detected in both arthropod vectors,with 66 known species of biting midges reported to carry potential pathogens,including Asaia lannensis and Rickettsia bellii,compared to 50 in ticks,such as Acinetobacter lwoffii and Staphylococcus *** found that Proteobacteria was the most dominant group in both midges and ***,the outcomes demonstrated that the microbiota of midges and ticks tend to be governed by a few highly abundant *** sp7 was predominant in biting midges,while Coxiella sp1 was enriched in ***,Coxiella spp.,which may be essential for the survival of Haemaphysalis longicornis Neumann,were detected in all tick *** identification of dominant species and pathogens of biting midges and ticks in this study serves to broaden our knowledge associated to microbes of arthropod *** Biting midges and ticks carry large numbers of known and potentially novel bacteria,and carry a wide

关键词： Biting midge Tick Microbiota Pantoea Coxiella

Inhibition of KU70 and KU80 by CRISPR interference,not NgAgo interference,increases the efficiency of homologous recombination in pig fetal fibroblasts

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Journal of Integrative Agriculture 2019年第2期18卷 438-448页

作者： li Guo-ling QUAN Rong WANG Hao-qiang RUAN Xiao-fang MO Jian-xin ZHONG Cui-li YANG Huaqiang li Zi-cong GU Ting liU De-wu WU Zhen-fang CAI Geng-yuan ZHANG Xian-wei National engineering Research Center for Breeding Swine Industry College of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642P.R.China Wens Foodstuff Group Co. Ltd.Yunfu 527400P.R.China

Non-homologous end-joining(NHeJ) is a predominant pathway for the repair of DNA double-strand breaks(DSB). It inhibits the efficiency of homologous recombination(HR) by competing for DSB targets. To improve the efficiency of HR, multiple CRISPR interference(CRISPRi) and Natronobacterium gregoryi Argonaute(NgAgo) interference(NgAgoi) systems have been designed for the knockdown of NHeJ key molecules, KU70, KU80, polynucleotide kinase/phosphatase(PNKP), DNA ligase IV(liG4), and NHeJ1. Suppression of KU70 and KU80 by CRISPRi dramatically promoted(Pe efficiency of HR to 1.85-and 1.58-fold, respectively, whereas knockdown of PNKP, liG4, and NHeJ1 repair factors did not significantly increase(P>0.05) HR efficiency. Interestingly, although the NgAgoi system significantly suppressed(PliG4, and NHeJ1 expression, it did not improve(P>0.05) HR efficiency in primary fetal fibroblasts. Our result showed that both NgAgo and catalytically inactive Cas9(dCas9) could interfere with the expression of target genes, but the downstream factors appear to be more active following CRISPR-mediated interference than that of NgAgo.

关键词： homologous recombination non-homologous end-joining CRISPRi NgAgoi KU70 KU80

Construction and research of Thermal engineering key specialty of Application-Oriented Talents Cultivation

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Construction and research of Thermal Engineering key special...

The Research on Absorption of Pressure-induced Near-infrared though Tissue in Vivo

2013年教育技术与管理科学国际会议

作者： li Jiu-ru MeNG ling-kun Harbin University of Science and Technology HUST

Thermal engineering specialty of Harbin University of Science and Technology, in the process of construction of key specialty,, formed a thick essential, wide platform and high quality with construction system is conducive to optimizing the structure of specialty disciplines, deepen the reform of promoting the teaching and research and teaching, strengthen the construction of specialty content. Improving the quality of personnel training, specialty competence, to meet the needs of the economic and Social Development;by updating the concept of education, strengthen the construction of teaching staff, strengthening the construction of teaching conditions, reform of Practice Teaching link, the reform of teaching contents and teaching methods and means;strong impetus to the application-oriented talents cultivation.

关键词： Application—Oriented Talents Thermal engineering key specialty specialty competence

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Chinese Journal of Biomedical engineering(english edition) 2005年第4期14卷 176-184页

作者： WANG ling-bo ZHOU li LU Yu li Kai-yang Laboratory of Biophysics and Biomedical englneering Department of Physics Wuhan University Wuhan 430072 China

Near-infrared imaging can be used to reconstruct tissue optical properties from measurements of light propagation through tissue. But a single static image alone does not reveal much information about abnormal vascularization because light beams are heavily scattered and diffused by tissues, resulting in very low spatial resolution. If changes caused by re-distribution of blood volume and oxygenation level are detected, more pathophysiologic information will be revealed. The goal of this work is to understand how the pressure that is applied to the surface affects the composition of the tissue and illustrate that the pressure-induced changes are significant and that are likely dependent on the tissue composition. In this paper, we propose a novel method to make continue-wave light illuminate the vivo tissue with external pressure, using the CCD camera to acquire sequential dynamic images during the whole course. The dynamic response of the tissue to pressure modulation is carried in the intensity variations among different images. This trial can prove that the pressure can influence the blood capacity and the oxygen saturation of the tissue in near-infrared imaging. The result can be output by dynamic value curves of the light intensity, at the same time some algorithms can be used to process image sequences, accumulating continuous physiology information in the resulting images, so the blood vessels can be shown more obviously. This is very useful to the physicians for the information of the blood vessel implicates much pathology information.

关键词： Pressure-induced Near-infrared Hemoglobin Dynamic value

Ginsenoside Rd attenuates Aβ-induced tau phosphorylation via altering the functional balance of glycogen synthase kinase-3β and protein phosphatase-2A

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Ginsenoside Rd attenuates Aβ-induced tau phosphorylation vi...