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高寒草原退化过程中植被和土壤因子对微生物群落的交互影响

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环境科学 2024年第7期45卷 4251-4265页

作者：徐欢丁明军张华张月菊黄鹏吴宇萍邹天娥王能玉曾欢江西师范大学地理与环境学院南昌330022 江西师范大学鄱阳湖湿地与流域研究教育部重点实验室南昌330022

为了探明青藏高原高寒草原退化过程中植被和土壤因子对土壤微生物群落的调节作用,以青藏高原三江源区高寒草原为研究对象,分析了不同退化阶段(未退化、中度退化和重度退化)高寒草原植被及土壤因子的差异,利用高通量测序技术分析了不同... 详细信息

为了探明青藏高原高寒草原退化过程中植被和土壤因子对土壤微生物群落的调节作用,以青藏高原三江源区高寒草原为研究对象,分析了不同退化阶段(未退化、中度退化和重度退化)高寒草原植被及土壤因子的差异,利用高通量测序技术分析了不同退化阶段微生物群落特征,并借助冗余分析(RDA)和基于相似或相异度矩阵的多元回归(MRM)识别影响微生物(细菌和真菌)群落变化的关键环境因子.结果表明,高寒草原退化显著改变了群落盖度、高度、生物量及禾本科重要值,降低了土壤有机质、全氮、全磷含量和粉粒含量,增加了土壤容重和砂粒含量.退化并未改变细菌和真菌的组成,但改变了组成比例,导致了微生物丰富度(Chao1指数和Richness指数)的损失,但并未显著改变微生物多样性(Shannon指数),随着退化的发生,植被特征、土壤理化性质与微生物多样性呈现出了一致的变化趋势.结合网络拓扑变化特征(网络的节点数和聚类系数显著下降)发现,高寒草原退化导致了微生物的种间相互作用减弱,网络结构更加分散,微生物的分布趋向于均质化,但物种间的相互作用仍然以合作为主(网络正相关连接占比>90%).高寒草原退化过程中植被-土壤的耦合对土壤细菌群落的影响最大,而土壤理化性质对土壤真菌的群落影响最大.具体而言,植被群落高度、生物量及土壤容重是调节土壤微生物的共性因子,植被辛普森指数、禾本科重要值、土壤全磷、全钾和粉粒含量是影响土壤细菌群落的特有因子;而土壤pH和全氮含量是影响土壤真菌群落的特有因子.

关键词：退化高寒草原土壤微生物植被特征土壤理化性质共现网络

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膜分离技术在沼气提纯中的应用

山东化工 2024年第9期53卷 282-284,287页

作者：刘明龙乔如林余能德州蓝德再生资源有限公司山东德州253000 深高蓝德环保科技集团股份有限公司河南郑州450000

餐厨垃圾是一种生物质废弃物,可通过微生物分解作用,转化为可再利用的沼气。沼气的主要成分是甲烷和二氧化碳,其中二氧化碳含量约占20%~40%,这使得沼气的能量密度较低,限制了其应用。主要研究膜分离技术提纯沼气制天然气,通过优化工艺设... 详细信息

餐厨垃圾是一种生物质废弃物,可通过微生物分解作用,转化为可再利用的沼气。沼气的主要成分是甲烷和二氧化碳,其中二氧化碳含量约占20%~40%,这使得沼气的能量密度较低,限制了其应用。主要研究膜分离技术提纯沼气制天然气,通过优化工艺设计,解决了沼气膜分离过程中膜系统温降、膜塑化、膜污染的问题。分析了膜分离工艺的主要控制参数压力、温度对产品气、排放气的影响,研究发现,适宜的进气压力1.35 MPa,温度25~30℃,可达到最佳的综合分离效果。研究可为膜分离技术提纯沼气的装置设计和工艺运行提供技术参考。

关键词：餐厨垃圾沼气天然气提纯膜分离

Coercivity enhancement of hot-deformed Nd-Fe-B magnets with Pr-Cu alloy addition

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Rare Metals 2023年第4期42卷 1403-1407页

作者： Jun-Ming Wang Zhao-Hui Guo Zheng Jing Xiao Du neng-Jun yu Meng-yu Li Ming-Gang Zhu Wei Li Division of Functional Materials Central Iron&Steel Research InstituteBeijing100081China

Effects of low-melting Pr-Cu alloy addition on the microstructure and magnetic properties of the hot-deformation Nd-Fe-B magnets were investigated.A small amount of Pr-Cu addition enhances the coercivity of the hot-deformation Nd-Fe-B magnets *** coercivity of the hotdeformation Nd-Fe-B magnets with 4.0 wt%Pr_(85)Cu_(15)addition increases to 1271 kA·m^(-1),75.69%higher than that of Pr-Cu-free magnet(723 kA·m^(-1)),and then decreases with5 wt%Pr_(85)Cu_(15)*** is observed that there a uniform RE-rich phase is formed wrapping the Nd2Fe14B main phase in the sample with 4.0%Pr_(85)Cu_(15)addition by scanning electron microscopy(SEM),which promotes the *** angular dependence of coercivity for the hot-deformation Nd-Fe-B magnets indicates that the coercivity mechanism is nucleation combined with domain wall *** domain wall pinning is weakened,while the nucleation is enhanced after Pr-Cu ***,intrinsic coercivity,and maximum magnetic energy product of the original Nd-Fe-B magnet are 1.45 T,723 kA·m^(-1),and 419.8 kJ·m^(-3),respectively,and those of the sample with 4.0%Pr_(85)Cu_(15)alloy addition are 1.30 T,1271 kA·m^(-1),and 330.0 kJ·m^(-3),respectively.

关键词： Nd-Fe-B Low-melting alloy Hot-deformation Microstructure Coercivity mechanism

脑血容量指数预测急性缺血性卒中患者血管内治疗远期预后的价值分析

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实用医院临床杂志 2024年第2期21卷 110-114页

作者：张琦杨树成旭东黎炳护余能伟电子科技大学四川成都610054 四川省医学科学院·四川省人民医院神经内科四川成都610072 西南医科大学四川泸州646000

目的探讨CT灌注指数与急性缺血性卒中(AIS)患者血管内治疗(EVT)远期预后的相关性。方法纳入64例诊断AIS且经EVT的患者并进行1年随访。主要结局指标包括术后1年改良Rankin量表(mRS)评分0~2分(良好预后)。所有患者根据低灌注强度比(HIR)(0... 详细信息

目的探讨CT灌注指数与急性缺血性卒中(AIS)患者血管内治疗(EVT)远期预后的相关性。方法纳入64例诊断AIS且经EVT的患者并进行1年随访。主要结局指标包括术后1年改良Rankin量表(mRS)评分0~2分(良好预后)。所有患者根据低灌注强度比(HIR)(0.7 vs≤0.7)进行分组,将组间临床资料及术后1年mRS评分进行比较;通过Logistic回归分析术后1年良好预后的影响因素。结果61例患者完成随访,其中术后1年达到良好预后的有34例(55.7%)。高CBV组良好预后率明显高于低CBV组(76.9%vs 40%),低HIR组良好预后率明显高于高HIR组(73.9%vs 44.7%)(P<0.05)。CBV指数是术后1年良好预后的保护因素(P=0.046)。结论CBV指数可预测AIS患者EVT远期预后情况,有望为患者EVT提供临床依据。

关键词：急性缺血性卒中血管内治疗 CT灌注脑血容量指数低灌注强度比

Genetic Analysis of Structural Styles in the Makran Accretionary Wedge–Insight from Physical Simulations

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Journal of Ocean University of China 2024年第1期23卷 157-172页

作者： SHAO Longfei yu Fusheng GONG Jianming LIAO Jing yu Zhifeng TANG Liang CHEN Jiangong WANG yuefeng neng yuan School of Earth Sciences China University of PetroleumBeijing 102249China State Key Laboratory of Petroleum Resources and Processing China University of PetroleumBeijing 102249China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China China University of Petroleum–Beijing at Karamay Karamay 834000China

The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the formation mechanism of shallow normal faults, remain unclear. Meanwhile, the factors affecting the continuity of plane faults must be comprehensively discussed. Clarifying the development characteristics and deformation mechanisms of the Makran accretionary wedge is crucial to effectively guide the exploration of gas hydrate deposits in the area. This study aims to interpret seismic data to identify typical structures in the Makran accretionary wedge, including deep imbricate thrust faults, shallow and small normal faults, wedge-shaped piggyback basins, mud diapirs with fuzzy and disorderly characteristics of reflection, décollements with a northward tilt of 1° – 2°, and large seamounts. Physical simulation-based experiments are performed to comprehensively analyze the results of the plane, section, and slices of the wedge. Results reveal that the distances between and shapes of thrust faults in the deep parts of the Makran accretionary wedge are controlled by the bottom décollement. The uplift of the thrust fault-related folds and the upwelling of the mud diapirs primarily contribute to the formation of small normal faults in the shallow part of the area. The mud diapirs originate from plastic material at the bottom, while those that have developed in the area near the trench are larger. Seamounts and mud diapirs break the continuity of fault plane distribution.

关键词： Makran accretionary wedge structural styles faults distribution physical simulation

Demethylase-assisted site-specific detection of N^(1)-methyladenosine in RNA

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Chinese Chemical Letters 2024年第5期35卷 397-401页

作者： Jun Xiong Ke-Ke Chen neng-Bin Xie Wei Chen Wen-Xuan Shao Tong-Tong Ji Si-yu yu yu-Qi Feng Bi-Feng yuan College of Chemistry and Molecular Sciences Research Center of Public HealthRenmin Hospital of Wuhan UniversitySchool of Public HealthWuhan UniversityWuhan 430071China Department of Laboratory Medicine Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China

The dynamic RNA modifications have been viewed as new posttranscriptional regulator in modulating gene expression as well as in a broad range of physiological processes.N^(1)-methyladenosine(m^(1)A)is one of the most prevalent modifications existing in multiple types of ***-depth investigation of the functions of m^(1)A requires the site-specific assessment of m^(1)A stoichiometry in ***,we established a demethylase-assisted method(DA-m^(1)A)for the site-specific detection and quantification of m^(1)A in RNA.N^(1)-methyl group in m^(1)A could result in the stalling of reverse transcription at m^(1)A site,thus producing the truncated *** AlkB is a demethylase that can demethylate m^(1)A to produce adenine in RNA,thus generating full-length cDNA from AlkB-treated *** of the produced amounts of full-length cDNA by quantitative real-time PCR can achieve the site-specific detection and quantification of m^(1)A in *** the DA-m^(1)A method,we examined and successfully confirmed the previously well-characterized m^(1)A sites in various types of RNAs with low false positive *** addition,we found that the level of m^(1)A was significantly decreased at the bromodomain containing 2(BRD2)mRNA position 1674 and CST telomere replication complex component 1(CTC1)mRNA position 5643 in human hepatocellular carcinoma *** results suggest that these two m^(1)A sites in mRNA may be involved in liver *** together,the DA-m^(1)A method is simple and enables the rapid,cost-effective,and site-specific detection and quantification of m^(1)A in RNA,which provides a valuable tool to decipher the functions of m^(1)A in human diseases.

关键词： N^(1)-methyladenosine RNA modification AlkB demethylase RNA epigenetics Quantitative real-time PCR Hepatocellular carcinoma

Novel lignans from the stems and leaves of Trachelospermum jasminoides

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Chinese Chemical Letters 2011年第9期22卷 1075-1077页

作者： Ling Jing neng Jiang yu yu Shan Li Le Fu Yi Min Zhao Institute of Pharmacology and Toxicology Academy of Military Medical Sciences Beijing 100850 China School of Traditional Chinese Medicines Shenyang Pharmaceutical University Shenyang 110016 China

Two novel 5-methoxydibenzylhydroxybutyrolactone lignans named 5-methoxytracheloside and 5-methoxytrachelogenin were isolated from the stems and leaves of Trachelospermumjasminoides （Lindl.） Lem., their structures were determined as （8S, 8＇S）-8＇- hydroxy-3, 3＇, 4, 5-tetramethoxylignan-9, 9＇-olide-4＇-O-β-o-glucopyranoside and （8S, 8＇S）-4＇, 8＇-dihydroxy-3, 3＇, 4, 5-tertramethoxylignan-9, 9＇-olide by various spectroscopic analysis. 5-Methoxytracheloside was a new compound and 5-methoxytrachelogenin was isolated from natural source for the first time.

关键词： Trachelospermum jasminoides 5-Methoxytracheloside 5-Methoxytrachelogenin

A New Norditerpene from Miliusa balansae Finet et Gagnep

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Chinese Chemical Letters 2001年第3期12卷 247-248页

作者： Rui WU Qi YE neng yu CHEN Guo Lin ZHANG Chengdu Institute of Biology the Chinese Academy of SciencesChengdu 610041 Department of Chemistry and Chemical Industry Lanzhou UniversityLanzhou 730000 Technical Centre Hua Sheng Group Co.LtdChengdu 610075

A novel norditerpene, miliusate (1), was isolated from Miliusa balansae et Gagnep. Its structure was elucidated by spectral analysis.

关键词： Miliusa balansae Finet et Gagnep. miliusate.

Demonstration of controlled high-dimensional quantum teleportation

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 1-6页

作者： Min-yu Lv Xiao-Min Hu neng-Fei Gong Tie-Jun Wang yu Guo Bi-Heng Liu yun-Feng Huang Chuan-Feng Li Guang-Can Guo CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China CAS Centerfor Excellence in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

Controlled quantum teleportation(CQT), which is regarded as the prelude and backbone for a genuine quantum internet, reveals the cooperation, supervision, and control relationship among the sender, receiver, and controller in the quantum network within the simplest unit. Compared with low-dimensional counterparts, high-dimensional CQT can exhibit larger information transmission capacity and higher superiority of the controller's authority. In this article, we report a proof-of-principle experimental realization of three-dimensional(3D) CQT with a fidelity of 97.4% ± 0.2%. To reduce the complexity of the circuit, we simulate a standard 4-qutrit CQT protocol in a 9×9-dimensional two-photon system with high-quality operations. The corresponding control powers are 48.1% ± 0.2% for teleporting a qutrit and 52.8% ± 0.3% for teleporting a qubit in the experiment, which are both higher than the theoretical value of control power in 2-dimensional CQT protocol(33%). The results fully demonstrate the advantages of high-dimensional multi-partite entangled networks and provide new avenues for constructing complex quantum networks.

关键词： high dimension quantum information quantum teleportation quantum nonlocality

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