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High-Pressure Behavior of Ferromagnesite(Mg_(0.81)Fe_(0.19))CO_(3)by Synchrotron X-Ray Diffraction and Raman Spectroscopy up to 53 GPa

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Journal of Earth Science 2024年第2期35卷 525-535页

作者： Lin Liang Guibin Zhang shengxuan huang Jingjing Niu Dongzhou Zhang Jingui Xu Wen Liang Shan Qin Key Laboratory of Orogenic Belts and Crustal Evolution MOEand School of Earth and Space SciencesPeking UniversityBeijing100871China CAS Center of Excellence in Tibetan Plateau Earth Sciences and Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China Hawai’i Institute of Geophysics and Planetology School of Ocean and Earth Science and TechnologyUniversity of Hawai’i at ManoaHawai’i96822USA Key Laboratory of High Temperature and High Pressure Study of the Earth’s Interior Institute of GeochemistryChinese Academy of SciencesGuiyang550081China

Ferromagnesite(Mg,Fe)CO_(3)with 20 mol%iron is a potential host mineral for carbon transport and storage in the Earth *** high-pressure behavior of synthetic ferromagnesite(Mg_(0.81)Fe_(0.19))CO_(3)up to 53 GPa was investigated by synchrotron X-ray diffraction(XRD)and Raman *** iron bearing carbonate underwent spin transition at around 44–46 GPa accompanied by a volume collapse of 1.8%,which also demonstrated a variation in the dνi/dP slope of the Raman *** pressure-volume data was fitted by a third-order Birch-Murnaghan equation of state(BM-EoS)for the high spin *** best-fit K_(0)=108(1)GPa and K_(0)'=4.2(1).Combining the dνi/dP and the K_(0),the mode Grüneisen parameters of each vibrational mode(T,L,ν4 andν1)were *** effects of iron concentration on the Mg_(1−x)Fe_(x)CO_(3)system related to high-pressure compressibility and vibrational properties are *** results expand the knowledge of the physical properties of carbonates and provide insights to the potential deep carbon host.

关键词： ferromagnesite synchrotron XRD Raman spectroscopy high pressure geochemistry mineral

Chemical Stability and Thermal Equation of State of SiN: Implications for Nitrogen Storage in the Deep Earth

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Journal of Earth Science 2024年

作者： Jingyi Zhang shengxuan huang Shan Qin Stella Chariton Vitali B.Prakapenka Bin Chen Geodynamics Research Center Ehime University Center for Advanced Radiation Sources University of Chicago Hawai?i Institute of Geophysics and Planetology University of Hawai?i at Mānoa Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space Sciences Peking University

Most nitrogen is predicted to reside in the Earth’s interior and could be in the form of nitrides. In this study， the chemical reaction of Si3N4with SiO2was explored up to 50 GPa and 2600 K using laser-heated diamond anvil cells combined with synchrotron radiation X-ray diffraction. The experimental results demonstrate that Si3N4does not react with SiO2and cubic γ-Si3N4remains stable at extreme pressure and temperature. First-principles calculations were performed to investigate the chemical stability of Si3N4with the SiO2-MgO assemblage， showing that Si3N4can coexist with Mg2SiO4and MgSiO3polymorphs. Based on our thermal equation of state of cubic γ-Si3N4， we suggest that cubic γ-Si3N4is denser than the upper mantle but less dense than the lower mantle. The formation of Si3N4in the early Earth may contribute to the nitrogen preservation in the deep mantle soon after crystallization of the mantle and Si3N4is likely a precursor of nitrogen hosts in the modern deep Earth.

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贝伐单抗联合洛莫司汀治疗复发性胶质母细胞瘤疗效与安全性的Meta分析

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武警医学 2024年第2期35卷 150-156页

作者：丁秀蓉刘金龙黄生炫李志宏武警特色医学中心急诊医学科天津300162 陆军第79集团军医院妇产科辽阳111000 福建医科大学附属三明市第一医院神经外科 365000

目的系统评价贝伐单抗联合洛莫司汀治疗复发性胶质瘤的临床疗效与安全性。方法全面检索中英文数据库,检索随机对照试验中探讨复发性胶质瘤患者使用贝伐单抗与洛莫司汀联合治疗的临床研究,检索时间均从建库至2023-04。2名研究者分别独立... 详细信息

目的系统评价贝伐单抗联合洛莫司汀治疗复发性胶质瘤的临床疗效与安全性。方法全面检索中英文数据库,检索随机对照试验中探讨复发性胶质瘤患者使用贝伐单抗与洛莫司汀联合治疗的临床研究,检索时间均从建库至2023-04。2名研究者分别独立检索数据库,筛查文献后对数据进行提取、分析,并分析纳入文献的偏倚风险,采用RevMan 5.4软件进行Meta分析。结果纳入6项随机对照试验,共有患者1053例(试验组523例,对照组530例)。Meta分析结果显示,贝伐单抗联合洛莫司汀治疗可显著改善复发性胶质母细胞瘤患者的无进展生存期(PFS)(HR=0.52,95%CI:0.44~0.61,P<0.05)与客观缓解率(ORR)(OR=0.33,95%CI:0.14~0.78,P<0.05),对总生存期(OS)无明显改善作用(HR=0.89,95%CI:0.75~1.07,P<0.05)。不良反应方面,贝伐单抗联合洛莫司汀治疗组的蛋白尿及三级以上不良反应发生率显著高于对照组,差异有统计学意义(P<0.05),其他不良反应与对照组比较,差异无统计学意义。结论贝伐单抗联合洛莫司汀治疗复发性胶质瘤可显著改善PFS、ORR,可优先推荐用于治疗复发性胶质母细胞瘤。同时,贝伐单抗与洛莫司汀联合治疗也与蛋白尿及三级以上不良反应率增加相关,因此在将贝伐单抗加入洛莫司汀方案之前,安全性仍需考虑。

关键词：复发性胶质母细胞瘤贝伐单抗洛莫司汀

Effect of Iron on the Stability of Rhodochrosite at the Topmost Lower Mantle Conditions

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Journal of Earth Science 2022年

作者： Tianlei Zhai Fei Qin shengxuan huang Shan Qin Yu Gong Key Laboratory of Orogenic Belts and Crustal Evolution， Ministry of Education， School of Earth and Space Sciences， Peking University School of Earth Sciences and Resources， China University of Geosciences (Beijing) Beijing Synchrotron Radiation Facility， Institute of High Energy Physics， Chinese Academy of Sciences

Carbonates are viewed as the principal oxidized carbon carriers during subduction， and thus the stability of subducted carbonates has significant implications for the deep carbon cycle. Here we investigate the high pressure-temperature behaviors of rhodochrosite in the presence of iron up to ～34 GPa by in-situ X-ray diffraction and ex-situ Raman spectroscopy. At relatively low temperature below ～1500 K， MnCO;breaks down into MnO and CO;. Upon heating to ～1800 K， however， the MnCO;-Fe;reactions occur with the formation of Mn;O;， FeO and reduced carbon. A ‘three-stages’ reaction mechanism is proposed to understand the kinetics of the carbon-iron-manganese redox coupling. The results suggest that Fe;can serve as a reductant to greatly affect the stability of rhodochrosite， which implies that the effect of Fe-metal should be seriously considered for the high pressure-temperature behaviors of other predominant carbonates at Earth’s mantle conditions， particularly at depths greater than ～250 km.

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Elasticity and Anisotropy of the Pyrite-Type FeO2H-FeO2 System in Earth’s Lowermost Mantle

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Journal of Earth Science 2019年第6期30卷 1293-1301页

作者： shengxuan huang Shan Qin Xiang Wu Key Laboratory of Orogenic Belts and Crustal Evolution MOESchool of Earth and Space SciencesPeking UniversityBeijing 100871China State Key Laboratory of Geological Processes and Mineral Resourses China University of GeosciencesWuhan 430074China

The pyrite-type FeO2 H-Fe O2 system has been experimentally confirmed to be stable in Earth's lowermost mantle but there is limited information about its physical properties at high pressures constraining our understanding of its potential geophysical implications for the deep ***,static calculations demonstrate that the pyrite-type FeO2 H-FeO2 system has a high density and Poisson's ratio and ultra-low seismic velocities at conditions of Earth's lowermost *** provides a plausible mechanism for the origin of ultra-low velocity zones at Earth's D″*** incorporation of hydrogen in the pyrite-type FeO2H-FeO2 system tends to decrease the S wave velocity(VS)but increase the bulk sound velocity(VΦ),and can potentially explain the observed anti-correlation of VS and VΦin the lowermost ***,FeO2 H exhibits nearly isotropic whereas Fe O2 is highly anisotropic,which may help understand some seismic anisotropies at the core-mantle boundary.

关键词： FeO2H FeO2 ultra-low velocity zones D″layer anisotropy

颅内动脉瘤模型大鼠端粒长度与端粒结合蛋白基因表达变化

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检验医学与临床 2024年第12期21卷 1785-1789页

作者：唐政史新宇孔庆梅李清振韦亮亮付浩黄生炫宝鸡高新医院神经外科陕西宝鸡721013 宝鸡高新医院急诊科陕西宝鸡721013 福建医科大学附属三明市第一医院神经外科福建三明365000

目的探讨颅内动脉瘤(IA)大鼠外周血端粒长度及其结合蛋白基因表达变化,初步探讨IA的潜在机制。方法将24只SD雌性大鼠随机等分为两组,即对照组和IA模型组(以下简称模型组)。模型组结扎左侧颈总动脉、结扎双侧肾动脉后支、切除双侧卵巢,... 详细信息

目的探讨颅内动脉瘤(IA)大鼠外周血端粒长度及其结合蛋白基因表达变化,初步探讨IA的潜在机制。方法将24只SD雌性大鼠随机等分为两组,即对照组和IA模型组(以下简称模型组)。模型组结扎左侧颈总动脉、结扎双侧肾动脉后支、切除双侧卵巢,并于造模后1周喂同时含8%氯化钠和3%L-甲硫氨酸的饲料。对照组则仅暴露左侧颈总动脉和双肾20 min后缝合皮肤,喂常规饲料。两组大鼠分别于造模前和造模后6个月时进行眶下静脉丛取血并提取外周血基因组DNA,检测相对端粒长度。造模后6个月时处死前测量血压及检测血清中雌二醇、同型半胱氨酸(Hcy)水平,提取外周血总RNA并检测6种端粒结合蛋白[端粒重复序列结合因子1(TRF1)、端粒重复序列结合因子2(TRF2)、端粒保护蛋白1(POT1)、肾上腺皮质增生蛋白同源异构体(TPP1)、TRF1相互作用核蛋白2(TIN2)、阻滞活化蛋白1(RAP1)]基因表达水平的变化。处死后通过血管铸型观察IA形成情况。结果造模后6个月时,模型组大鼠收缩压和血清Hcy水平均高于对照组(P0.05);造模后6个月时,模型组大鼠端粒长度明显短于对照组,差异有统计学意义(P0.05)。结论IA模型大鼠造模后6个月时,外周血端粒长度明显缩短,端粒结合蛋白TRF2和TPP1基因表达水平上调,这可能与IA的病因机制相关。

关键词：端粒颅内动脉瘤端粒结合蛋白大鼠雌二醇同型半胱氨酸

Redox-Induced Destabilization of Dolomite at Earth’s Mantle Transition Zone

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Journal of Earth Science 2021年第4期32卷 880-886页

作者： Tianlei Zhai shengxuan huang Shan Qin Jingjing Niu Yu Gong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing 100871China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100094China

Carbonates are considered to be important hosts of oxidized carbon during subduction *** we investigate the redox interactions between dolomite and metallic iron in laser-heated diamond anvil cells up to~20 *** identification of recovered samples via in-situ synchrotron X-ray diffraction and ex-situ Raman spectroscopy shows that the reaction occurs with the formation of ferropericlase,graphite and hexagonal diamond,while CaCO_(3) remains *** experimental results indicate dolomite and metallic iron phases cannot coexist and demonstrate a possible formation mechanism of ultradeep diamonds via redox reaction between dolomite and iron under the mantle transition zone *** results are significant for understanding carbon transportation during subduction processes and have further implications to the processes in the more complex systems regarding to carbonate-silicate-metal phase relations.

关键词： deep carbon cycle carbonates interaction dolomite high pressure

3D genome organization and its study in livestock breeding

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Journal of Integrative Agriculture 2024年第1期23卷 39-58页

作者： Jie Cheng Xiukai Cao shengxuan Wang Jiaqiang Zhang Binglin Yue Xiaoyan Zhang Yongzhen huang Xianyong Lan Gang Ren Hong Chen Key Laboratory of Animal Genetics Breeding and Reproduction of Shaanxi ProvinceCollege of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China Yangzhou UniversityYangzhou 225009China College of Animal Science Xinjiang Agricultural UniversityUrumqi 830052China

Eukaryotic genomes are hierarchically packaged into cell nucleus,affecting gene *** genome is organized into multiscale structural units,including chromosome territories,compartments,topologically associating domains(TADs),and DNA *** identification of these hierarchical structures has benefited from the development of experimental approaches,such as 3C-based methods(Hi-C,ChIA-PET,etc.),imaging tools(2D-FISH,3D-FISH,Cryo-FISH,etc.)and ligation-free methods(GAM,SPRITE,etc.).In recent two decades,numerous studies have shown that the 3D organization of genome plays essential roles in multiple cellular processes via various mechanisms,such as regulating enhancer activity and promoter-enhancer ***,there are relatively few studies about the 3D genome in livestock ***,studies for exploring the function of 3D genomes in livestock are urgently needed to provide a more comprehensive understanding of potential relationships between the genome and production *** this review,we summarize the recent advances of 3D genomics and its biological functions in human and mouse studies,drawing inspiration to explore the 3D genomics of livestock *** then mainly focus on the biological functions of 3D genome organization in muscle development and its implications in animal breeding.

关键词： 3D genome organization 3D genomic methodology regulatory mechanisms muscle development livestock breeding

急性脑血管疾病患者血清微小RNA-7的表达变化及临床意义

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中华实验外科杂志 2024年第4期41卷 787-787页

作者：李静丁乔黄生炫王朝飞遵义市第一人民医院(遵义医科大学第三附属医院)神经内科遵义563000 福建医科大学附属三明市第一医院神经外科三明365000 遵义医科大学附属湄潭医院神经内科遵义564100

本研究旨在观察急性脑血管疾病(ACVD)患者血清中微小RNA(miRNA)-7的表达,并探讨了ACVD患者预后的相关性。

关键词：急性脑血管疾病 ACVD 表达变化临床意义患者预后相关性