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The effects of soil properties, cropping systems and geographic location on soil prokaryotic communities in four maize production regions across China

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Journal of Integrative Agriculture 2022年第7期21卷 2145-2157页

作者： TIAN Xue-liang LIU Jia-jia LIU Quan-cheng XIA Xin-yao PENG Yong Alejandra I.HUERTA yan jian-bing LI Hui LIU Wen-de State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China Henan Engineering Research Center of Biological Pesticide&Fertilizer Development and Synergistic Application Henan Institute of Science and TechnologyXinxiang 453003P.R.China School of Biological Science and Technology University of JinanJinan 250022P.R.China National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070P.R.China Department of Entomology and Plant Pathology North Carolina State UniversityRaleigh 27606USA

The diversity of prokaryotic communities in soil is shaped by both biotic and abiotic ***,little is known about the major factors shaping soil prokaryotic communities at a large scale in *** this end,we undertook a study to investigate the impact of maize production cropping systems,soil properties and geographic location(latitude and longitude)on soil prokaryotic communities using metagenomic techniques,across four distinct maize production regions in *** all study sites,the dominant prokaryotes in soil were Alphaproteobacteria,Gammaproteobacteria,Betaproteobacteria,Gemmatimonadetes,Acidobacteria,and ***-metric multidimensional scaling revealed that prokaryotic communities clustered into the respective maize cropping systems in which they *** analysis(RDA)showed that soil properties especially pH,geographic location and cropping system jointly determined the diversity of the prokaryotic *** functional genes of soil prokaryotes from these samples were chiefly influenced by latitude,soil pH and cropping system,as revealed by RDA *** abundance of genes in some metabolic pathways,such as genes involved in microbe–microbe interactions,degradation of aromatic compounds,carbon fixation pathways in prokaryotes and microbial metabolism were markedly different across the four maize production *** study indicated that the combination of soil pH,cropping system and geographic location significantly influenced the prokaryotic community and the functional genes of these *** work contributes to a deeper understanding of the composition and function of the soil prokaryotic community across large-scale production systems such as maize.

关键词： metagenome cropping system maize soil prokaryotes

Anti-ageing effects of a new Dimethylaminoethanol-based formulation on DGalactose induced skin ageing model of rat

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中国美容医学 2015年第5期24卷 1-8页

作者： yan bing-jian YUAN Feng ZHAO Cai-ling LIU Su Department of burn and Plastic Surgery The Affiliated Hospital of Medical SchoolQingdao University School of Medicine Qingdao University Technical Director Beijing Biodegradable Materials Engineering Laboratory Department of Burn and Plastic Surgery Laiwu People's Hospital Department of Plastic and Aesthetic Surgery The Affiliated Hospital of Medical SchoolQingdao University

Background Dimethylaminoethanol has been widely used to fight against wrinkles, in the field of aesthetic medicine there is an increasing demand for safe and effective Dimethylaminoethanol-based products to counteract the ageing process. Objective To evaluate the anti- ageing effects of a new DMAE- based formulation. Methods 30 male rats were randomly allocated into treatment,D-gal ageing modeland control groups, each of which contained ten *** group and D- gal ageing model group were subcutaneously injected with D- galactose prepared in normal saline 125mg·kg-1·d-1for 42 d. Control groups were injected with normal saline for42 d with same method and dose. From the 18 th day,after shaving their hair,the treatment grouprats were injected thisnew DMAE-based formulation at a dose of 1ml per week for 4 weeks in the Dermis of two sides hip skin mark ***,D-gal ageing model group rats were administrated the same volume of normal saline with same method. Skin specimens were obtained 3days after the last treatment. Dermal collagen density and dermal thickness were evaluated by H&E and Massontrichrome staining. And m RNA expressions of TGFβ1, Smad3, Type I,Type III Pro-collagen,TIMP-1,MMP- 1,were assessed by Real- time quantitative polymerase chain reaction. Results Dermal thickness, dermal collagen density and hydroxyproline content in treatment group increased significantly comparing with D- gal ageing model group. No differences were found in m RNA expression of MMP- 1 and Type III Pro- collagen between the treatment group and D- gal ageing model group. In addition, m RNA expression of TGFβ1, Type I Pre-collagen, TIMP1 and smad3 in treatment group were significantly up- regulated in contrast with D- gal ageing model and control group. Conclusion This new DMAE- based formulationcould generate anti- ageing effects by activating collagen synthesisthrough TGF-β1/Smads signaling pathway.

关键词： anti-ageing TGF-β1/Smads signaling pathway Dimethylaminoethanol

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金刚石基燃料电池催化剂的研究进展

无机材料学报 2017年第7期32卷 673-680页

作者：董亮王艳辉臧建兵东北大学秦皇岛分校河北省电介质与电解质功能材料重点实验室秦皇岛066004 燕山大学亚稳材料制备技术与科学国家重点实验室秦皇岛066004

金刚石是由共价键方式连接的sp^3杂化碳原子组成,具有极强的稳定性。含硼金刚石(BDD)薄膜、BDD颗粒、非掺杂纳米金刚石(ND)等新型金刚石又兼具一定的导电性,因此成为高稳定性燃料电池催化剂的理想载体材料。研究者进一步发现通过对上述... 详细信息

金刚石是由共价键方式连接的sp^3杂化碳原子组成,具有极强的稳定性。含硼金刚石(BDD)薄膜、BDD颗粒、非掺杂纳米金刚石(ND)等新型金刚石又兼具一定的导电性,因此成为高稳定性燃料电池催化剂的理想载体材料。研究者进一步发现通过对上述新型金刚石进行适当功能化处理,可以进一步提高催化剂的催化活性和稳定性。对金刚石进行掺杂处理,既包括向金刚石晶格中掺杂,也包括向金刚石衍生的石墨结构中进行掺杂,能够得到新型高稳定性燃料电池非铂催化剂,且金刚石sp^3结构在提高非铂催化剂稳定性方面作用独特。本文总结介绍了相关研究成果,希望能为后续研究提供参考借鉴。

关键词：金刚石燃料电池稳定性综述

玉米起源进化的“世纪之争”——且看技术进步和学科交叉如何解决重大科学问题

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玉米科学 2023年第6期31卷 1-6页

作者：严建兵华中农业大学/作物遗传改良全国重点实验室/湖北洪山实验室武汉430070

玉米作为世界种植最为广泛的作物之一,其起源问题一直争议不断。主要有两个假说,一个是保罗·芒格尔斯多夫提出的“三成分起源说”,另一个是乔治·比德尔提出的“大刍草单一起源假说”。分子生物学技术的发展,为单一起源假说提供了直接... 详细信息

玉米作为世界种植最为广泛的作物之一,其起源问题一直争议不断。主要有两个假说,一个是保罗·芒格尔斯多夫提出的“三成分起源说”,另一个是乔治·比德尔提出的“大刍草单一起源假说”。分子生物学技术的发展,为单一起源假说提供了直接证据,从而得到了科学界的共识。随着科学技术不断进步,许多研究发现,玉米的大刍草单一起源假说存在诸多解释不通的现象。综合利用考古学、分子生物学、群体遗传学等研究手段,中美学者联合提出了玉米起源的新模型,即“二次起源假说”。约9 000年前,玉米单一起源于小颖大刍草亚种;6 000年前后,玉米又与墨西哥高原亚种发生了一次杂交,发生了第二次驯化,现代玉米都是来自两个不同大刍草的后代。二次起源极大地提高了现代玉米的适应性,墨西哥高原亚种为现代玉米提供了高原适应性和广泛的抗性基因,这为今天玉米成为全球适应性最广和种植面积最大的作物奠定重要的物质基础。该模型为理解人为机制对作物驯化起源的影响提供了良好范例,并为利用野生资源进行作物遗传改良奠定重要理论基础。

关键词：玉米大刍草起源

竹木家具进出口贸易报关过程中税收法律问题探讨

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林产工业 2020年第2期57卷 104-106页

作者：严剑冰河南机电职业学院

在经济全球化的大趋势下,中国竹木家具进出口贸易发展迅速。从竹木家具进出口贸易报关过程中实际税收问题入手,深入分析了竹木家具进出口贸易税收方面存在的问题,并对竹木家具进出口贸易报关过程中的法律问题提出了针对性建议。

关键词：竹木家具进出口贸易现状税收法律问题建议

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密植高产——我国玉米育种的最核心目标

生物技术通报 2023年第8期39卷 1-3页

作者：严建兵赵久然华中农业大学作物遗传改良全国重点实验室北京市农林科学院玉米研究所玉米DNA指纹及分子育种北京市重点实验室

我国是人口大国，粮食安全是事关国家长治久安的重大战略问题。习近平总书记指出，中国人的饭碗任何时候都要牢牢端在自己手上。至2050年，全球人口将突破90亿，预计全球作物产量需要再提高一倍才能满足需求。在耕地资源日趋紧张、极端... 详细信息

我国是人口大国，粮食安全是事关国家长治久安的重大战略问题。习近平总书记指出，中国人的饭碗任何时候都要牢牢端在自己手上。至2050年，全球人口将突破90亿，预计全球作物产量需要再提高一倍才能满足需求。在耕地资源日趋紧张、极端气候和病虫害频发的形势下，继续提升粮食产量的关键在于提升单产水平。玉米是全球重要的粮食、饲料和能源作物，对保障世界粮食安全意义重大。

关键词：密植高产玉米育种极端气候