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Tracing the Methane Events by Stable Carbon Isotopes of Benthic Foraminifera at Glacial Periods in the Andaman Sea

Journal of Earth Science 2022年第6期33卷 1571-1582页

作者： Yue Cen Jiasheng Wang Xuan ding dorrik Stow Zhou Wang Can Chen Xiaochen ma Hubei Key Laboratory of marine Geological Resources College of Marine Science and TechnologyState Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesWuhan430074China School of the marine Sciences China University of GeosciencesBeijing100083China Institute of Geo-Energy Engineering Heriot-Watt UniversityEdinburghEH 144ASUK State Key Laboratory of marine Geology Tongji UniversityShanghai200092China

Stable isotopes of carbon and oxygen variations in foraminiferal shells have been widely used in paleo-environment ***,studies about the shells of benthic foraminifera in methanehydrate-bearing sediments as reliable geochemical proxies to reconstruct the potential methane release events in the geologic past are *** this study,we present the stable carbon and oxygen isotopes of fossil benthic foraminifera including one epifaunal species(Cibicidoides wuellerstorfi)and two infaunal species(Bulimina mexicana and Uvigerina peregrina)from the Site U1447 of iodP 353 Expedition to trace methane events in the Andaman Sea,where one of the thickest and deepest gas hydrate stability zones was ***δ^(13)C values of benthic foraminifera show that there are eight distinct intervals with negative values in the last~10 Myr,interpreted as a record of long-term fluctuations in methane *** of these methane events occurred during the glacial sea-level lowstands in the last~1.1 ***,therefore,infer that the trigger mechanism for these events might be the hydrate destabilization caused by sea level *** methane events that occurred at~2.11 and~5.93 ma are more likely related to the sudden changes in sedimentation,either slide events or marked variations in sedimentation rate.

关键词： benthic foraminifera stable carbon and oxygen isotopes methane events gas hydrates iodP 353 Site U1447 Andaman Sea

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基于非靶向代谢组学技术解析老白干白酒发酵过程中的代谢物特征

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食品科学技术学报 2024年第4期42卷 45-60页

作者：耿晓杰陈尔豹马志莹王新磊王柏文郑福平孙金沅张煜行李泽霞北京工商大学中国轻工业酿酒分子工程重点实验室/食品质量与安全北京实验室/中国轻工业酒类品质与安全重点实验室北京100048 河北衡水老白干酒业股份有限公司河北衡水053000

白酒发酵过程中的代谢物与其独特的风格特征息息相关。对于老白干白酒而言,其发酵过程中代谢物的特征及其变化规律尚未被完全解析。采用超高效液相色谱-串联质谱联用技术,对老白干白酒发酵过程中的酒醅代谢物进行了鉴定,通过主成分分析... 详细信息

白酒发酵过程中的代谢物与其独特的风格特征息息相关。对于老白干白酒而言,其发酵过程中代谢物的特征及其变化规律尚未被完全解析。采用超高效液相色谱-串联质谱联用技术,对老白干白酒发酵过程中的酒醅代谢物进行了鉴定,通过主成分分析和显著性差异分析,筛选出了差异代谢物,并通过KEGG数据库注释分析,揭示了这些差异代谢物可能参与的代谢途径。结果表明,在9个不同发酵时间点的酒醅样品中,共检测到2157种代谢物,其中172种为极显著差异代谢物(VIP>2,P0.1)。在不同发酵阶段,各类代谢物的表达量有所不同。在发酵前期(0~8 d)差异代谢物最多,共128种极显著差异代谢物(Pd)有22种代谢物有极显著差异代谢物(Pd)代谢显著上调,脂类代谢先上调后下调,黄酮类与之相反;发酵后期(17~36 d)有33种极显著差异代谢物(P<0.01),氨基酸、肽及其类似物和脂类代谢先上调后下调。此外,通过KEGG数据库注释,确定了104条代谢途径,并据此绘制了代谢网络图。在发酵的不同阶段,某些代谢途径变得更为活跃,如碳水化合物代谢、脂类代谢、黄酮类代谢和氨基酸代谢主要发生在发酵前期(P<0.05),而黄酮类代谢在发酵中期较为活跃(P<0.05),脂类代谢和氨基酸代谢则在发酵后期较为旺盛(P<0.05)。丝氨酸、谷氨酰胺和天冬氨酸半醛等18种代谢物在多个发酵时间段表现出显著差异,它们注释到半乳糖代谢,甘氨酸、丝氨酸和苏氨酸代谢,精氨酸和脯氨酸代谢,苯丙氨酸、酪氨酸和色氨酸生物合成及甘油磷脂代谢等途径,这可能是风味化合物的潜在生成途径。研究基于代谢组学技术,揭示了老白干白酒发酵过程中代谢物的特征及其变化规律,可为解析老白干白酒发酵过程中的风味代谢机制提供理论依据。

关键词：老白干风味化合物酒醅代谢组学代谢途径

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银川市2016-2022年手足口病柯萨奇病毒A6型分离株VP1基因特征分析

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宁夏医学杂志 2024年第1期46卷 19-23页

作者：秦红张伟宏马杰纳玮马晓瑞王彦海王光俊樊瑞军银川市疾病预防控制中心宁夏银川750002 宁夏回族自治区人民医院临床医学检验诊断中心宁夏银川750011

目的分析银川市2016-2022年引起手足口病的柯萨奇病毒A6型(CV-A6)VP1的基因特征,为手足口病的防治工作提供有效的参考依据。方法收集2016-2022年银川市手足口病所有CV-A6核酸呈阳性的标本进行病毒分离培养,应用一步法聚合酶链式反应(R... 详细信息

目的分析银川市2016-2022年引起手足口病的柯萨奇病毒A6型(CV-A6)VP1的基因特征,为手足口病的防治工作提供有效的参考依据。方法收集2016-2022年银川市手足口病所有CV-A6核酸呈阳性的标本进行病毒分离培养,应用一步法聚合酶链式反应(RT-PCR)扩增其VP1区完整基因核酸片段进行核苷酸序列测定,利用测序结果进行系统发育树构建、同源性分析及氨基酸突变位点分析。结果 2016-2022年银川市共分离到手足口病CV-A6型毒株90株,测序后成功获得CV-A6 VP1区全长序列的毒株83株。完整VP1区基因均由915个核苷酸组成,编码305个氨基酸。系统发育分析显示,2016-2022年银川市83株CV-A6分离株均属于d3基因亚型的d3a分支;同源性分析表明,银川市83株CV-A6分离株与原型株Gdula株(AY421764-USA-1949)之间核苷酸相似性为82.1%~84.1%,氨基酸相似性为76.2%~80.5%,遗传距离较远;银川市83株CV-A6分离株与原型株Gdula株的VP1区氨基酸序列比较发现32个氨基酸位点出现变异。结论 2016-2022年银川市手足口病83株CV-A6分离株均属于d3基因亚型的d3a分支。加强对CV-A6的持续监测及基因特征分析,对科学防控CV-A6引起的手足口病及其疫苗研发具有重要意义。

关键词：手足口病柯萨奇病毒A6型基因特征分析

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Micro RNA-145 exerts tumor-suppressive and chemoresistance lowering effects by targeting Cd44 in gastric cancer

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World Journal of Gastroenterology 2017年第13期23卷 2337-2345页

作者： Jian-Feng Zeng Xiao-Qiu ma Lin-Pei Wang Wei Wang department of General Surgery The Second Affiliated Hospital of Fujian Medical University department of Medical Oncology The 180th Hospital of the People's Liberation Army

AIM To determine the potential roles of Cd4 and micro RNA(mi R)-145 in gastric *** The levels of Cd44 and mi R-145 were determined in gastric cancer cells. Quantitative real-time polymerase chain reaction was used to measure to the level of Cd44 m RNA. A luciferase reporter assay and western blotting were performed to examine the effect of mi R-145 on Cd44 expression. Tumor sphere and MTT assays were carried out to evaluate the self-renewal and chemo-resistance properties of gastric cancer *** The expression of Cd44 was greatly increased and mi R-145 was decreased in gastric cancer cells that were highly enriched in cancer stem cells(CSCs). The results demonstrated that mi R-145 regulated Cd44 by targeting directly the Cd44 3'-untranslated region(3'-UTR). In gastric cancer cells, overexpression of mi R-145 repressed the activity of the Cd44 3'-UTR, and disruption of mi R-145/Cd44 3'-UTR interactions abrogated the silencing effects. In addition, mi R-145 inhibition stimulated Cd44 3'-UTR activity and disruption of mi R-145/Cd44 3'-UTR interactions abrogated this stimulatory effect. Enforced Cd44 expression greatly increased tumor sphere forma.ion and chemoresistance in gastric cancer cells. Furthermore, the inhibition of CSCs and the chemo-sensitivity of gastric cancer cells treated with mi R-145 were significantly abrogated by overexpression of Cd44. CONCLUSioN mi R-145 targeting of Cd44 plays critical roles in the regulation of tumor growth and chemo-resistance in gastric cancer.

关键词： miR-145 Cd44 Gastric cancer stem cells Chemo-resistance

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Effect of the benzene ring of the dispersant on the rheological characteristics of coal-water slurry:Experiments and theoretical calculations

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International Journal of Mining Science and Technology 2021年第3期31卷 515-521页

作者： Lin Li Chuandong ma Shanpei Hu Meng He Hao Yu Qingbiao Wang Xiaoqiang Cao Xiaofang You College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590China College of Safety and Environment Engineering Shandong University of Science and TechnologyQingdao 266590China National Engineering Laboratory for Coalmine Backfilling Mining Shandong University of Science and TechnologyTai’an 271019China department of Resource and Civil Engineering Shandong University of Science and TechnologyTai’an 271019China

In this study,low-rank coal-water slurry(LCWS)was prepared using polyoxyethylene dodecylphenol ether(PdPE)and polyoxyethylene lauryl ether(PLE),respectively.A combination of experiments and simulations was used to investigate the pulping properties and microscopic mechanism of the LCWS samples prepared using the two agents,so as to explore the influence of benzene ring on the performance of *** results of the LCWS preparation experiments revealed that the pulp-forming performance of PdPE exceeded that of *** LCWS concentration is 62%,64%,and 66%,the apparent viscosity corresponding to PdPE is 247.80,504.17,and 653.10 mPa·s,and the apparent viscosity corresponding to PLE is 548.10,1470.61,and 1549.98 mPa·s,*** C_(1000)(When the apparent viscosity is 1000 mPa·s,the corresponding concentration of LCWS is defined as C_(1000))values of PdPE and PLE are 67.60%and 62.95%,*** addition to the van der Waals forces and hydrogen bonds between the PdPE and/or PLE molecules and coal,the benzene rings of PdPE presentπ-πstacking effect with the aromatic rings of *** could facilitate and strengthen the adsorption of PdPE on coal,which would be conducive to further improving the dispersion of coal *** two dispersants have no significant difference in effect on the pyrolysis of *** simulation results indicated that the times for PdPE and PLE molecules to reach flat adsorption state on coal are approximately 290 and 565 ps,*** self-diffusion coefficient(d)of the PdPE and PLE on coal is 3.16 x 10^(-6)and6.57×10^(-6)m~2/s,respectively,and their interaction energies with coal are 785.71 and 648.60 kcal/mol,*** results of the simulation calculations demonstrated that PdPE adsorbed on coal easier than PLE,and its binding is more stable than that of PLE owing to theπ-πstacking effect,which is conducive to uniform dispersion of coal in *** simulation results confirmed the experimental results.

关键词： Low rank coal Low-rank coal-water slurry Benzene ring Molecular dynamics simulation

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Microstructure and mechanical property evolution of friction stir welded(B4C+Al2O3)/Al composites designed for neutron absorbing materials

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Science China(Technological Sciences) 2020年第7期63卷 1256-1264页

作者： ZAN YuNing WANG BeiBei ZHOU YangTao JIA CunLei LIU ZhenYu WANG QuanZhao XIAO BoLv ma ZongYi Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

(B4C+Al2O3)/Al composite designed for the dry storage of spent nuclear fuels was fabricated and then subjected to friction stir welding, at a welding speed of 100 mm/min and rotation rates of 400–800 r/min. Sound joints were obtained under all welding parameters;however, significant softening occurred in the nugget zone(NZ) for all the joints. Therefore, all the joints exhibited significantly decreased strength at both room temperature and high temperature compared with the base metal, with the joints fracturing in the NZs. Rotation rate exhibited no obvious effect on the tensile strength of the joints, but led to increased elongation as the result of the broadened NZs. The detailed microstructural examinations indicated that the welding thermomechanical effect broke up the near 3d amorphous Al2O3 netlike structure distributed at the Al grain boundaries, caused the coarsening of Al grains, and the agglomeration and crystallization of amorphous Al2O3, thereby resulting in the softening of the NZs and the reduction in the joint strength. Consequently, inhibiting the breakup and crystallization of 3d amorphous Al2O3 netlike structure is the key factor to improve the joint strength of the(B4C+Al2O3)/Al composite.

关键词： particle reinforced Al matrix composites neutron absorber materials FSW mechanical properties high-temperature strength

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直流氩等离子体射流电子温度的测量

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光谱学与光谱分析 2008年第1期28卷 6-9页

作者：严建华潘新潮马增益屠昕岑可法浙江大学热能工程研究所能源清洁利用国家重点实验室浙江杭州310027

直流等离子体射流的电子激发温度,是等离子体射流物理特性中的一个非常重要的参数,并且影响着射流中其他众多特征参数。文章采用发射光谱诊断技术对直流氩等离子体射流进行实验研究,对实验所测得的射流的光谱强度信号进行分析,并采用玻... 详细信息

直流等离子体射流的电子激发温度,是等离子体射流物理特性中的一个非常重要的参数,并且影响着射流中其他众多特征参数。文章采用发射光谱诊断技术对直流氩等离子体射流进行实验研究,对实验所测得的射流的光谱强度信号进行分析,并采用玻尔兹曼曲线斜率法计算等离子体射流的激发温度。实验结果表明,等离子体射流的激发温度在等离子体发生器的轴向上的分布,随着离出口的距离增大,激发温度显著地下降。并且激发温度受电流和流量的影响较大,提高电源的输出电流,或者增加氩气的流量,激发温度都会升高。

关键词：等离子体发射光谱诊断激发温度玻尔兹曼图解

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Impact of tropical Atlantic warming on the Pacific Walker circulation with numerical experiments of CGCM

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Advances in Climate Change Research 2021年第6期12卷 757-771页

作者： EN Si-Min ZHANG Shao-Qing LU Lü JIANG Ying-Jing ma You-Wei Key Laboratory of Physical Oceanography Ministry of Education/Institute for Advanced Ocean Study/Frontiers Science Center for Deep Ocean Multispheres and Earth System(DOMES)Ocean University of ChinaQingdao266000China Pilot National Laboratory for marine Science and Technology(QNLM) QingdaoChina International Laboratory for High-Resolution Earth System Model and Prediction(iHESP) Qingdao266000China The College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao266000China

The Pacific Walker circulation(PWC)was weak in the 20th century,but its strength increased in an interdecadal scale in the late *** studies have suggested that it could be caused by the warming of the tropical Atlantic Ocean,or induced by the warming of the tropical Indian *** tropical Atlantic Ocean would not only directly affect the PWC through the equatorial east Pacific to the west,but also produce an indirect effect to the east through the equatorial west Indian *** a coupled general circulation model,we designed a series of tropical Atlantic Heating and Heating_Shut experiments with different heating rates,to detect the mechanism of the impact of tropical Atlantic warming on the *** show that the tropical Atlantic heating weakens the Atlantic Walker circulation but strengthens the *** of multiple physical variables with coherent lowereupper troposphere structure show the responses of the Indian Ocean to the Atlantic heating play a critical role in the strengthening of the *** Atlanticelinked atmosphere over the tropical Indian Ocean exerts a significantly positive heat flux onto the ocean there,greatly warming the tropical Indian Ocean,especially on the west *** produces strong convectively ascending at the equatorial West Indian Ocean,but descending at the East-central Indian Ocean,corresponding to a‘Walker’circulation and an‘antieWalker’circulation situated at the West and East equatorial Indian Ocean ***,the convergence(divergence)of the lower(upper)troposphere over the Indo‒Pacific region is also *** this way,the tropical Atlantic heating is linked to the PWC through the circulation over the equatorial Indian *** study serves as a preliminary step to understand the impact of tropical Atlantic warming on the PWC,more Atlantic heating sensitivity studies with multi-model experiments are required to further reveal the linkage of the Pacific and Atlantic.

关键词： Tropical Atlantic warming Pacific Walker circulation Tropical Indian Ocean Model simulation

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髓样细胞触发受体2——缺血性脑卒中治疗的新靶点

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中国免疫学杂志 2024年第7期40卷 1510-1514页

作者：苗珠月魏汝恒刘可心韩光远宋丽娟马存根山西中医药大学神经生物学研究中心/国家中医药管理局多发性硬化益气活血重点研究室晋中030619 山西医科大学细胞生理学省部共建教育部重点实验室太原030001 山西大同大学脑科学研究所大同037009

缺血性脑卒中严重危害人类健康,有较高的致残致死率。小胶质细胞、星形胶质细胞等多种细胞参与其病理过程。小胶质细胞作为中枢神经系统(CNS)的固有免疫细胞,在机体生理、病理状态下均发挥重要作用。髓样细胞触发受体2(TREM2)是在CNS中... 详细信息

缺血性脑卒中严重危害人类健康,有较高的致残致死率。小胶质细胞、星形胶质细胞等多种细胞参与其病理过程。小胶质细胞作为中枢神经系统(CNS)的固有免疫细胞,在机体生理、病理状态下均发挥重要作用。髓样细胞触发受体2(TREM2)是在CNS中主要表达于小胶质细胞的一种免疫球蛋白样受体,可与多种配体结合,在自身免疫及炎症过程中主要发挥“负性调节”的有益作用,可参与增殖、吞噬、存活、炎症因子表达等。本文阐述小胶质细胞中TREM2的生物学特性、相应配体及其信号通路,探讨TREM2在缺血性脑卒中的调节及其潜在治疗作用,以期为缺血性脑卒中的防治新靶点提供参考。

关键词：髓样细胞触发受体2 小胶质细胞缺血性脑卒中

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Lightweight,Flexible Cellulose-derived Carbon Aerogel@Reduced Graphene Oxide/PdMS Composites with Outstanding EMI Shielding Performances and Excellent Thermal Conductivities

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Nano-Micro Letters 2021年第6期13卷 126-142页

作者： Ping Song Bei Liu Chaobo Liang Kunpeng Ruan Hua Qiu Zhonglei ma Yongqiang Guo Junwei Gu MOE Key Laboratory of material Physics and Chemistry under Extraordinary Conditions Shaanxi Key Laboratory of Macromolecular Science and TechnologySchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072P.R.China Xi’an ESWIN Silicon Wafer Technology Co.Ltd Xi’an 710100P.R.China

In order to ensure the operational reliability and infor-ma.ion security of sophisticated electronic components and to protect human health,efficient electromagnetic interference(EMI)shielding materials are required to attenuate electromagnetic wave *** this work,the cellulose solution is obtained by dissolving cotton through hydrogen bond driving self-assembly using sodium hydroxide(NaOH)/urea solution,and cellulose aerogels(CA)are prepared by gelation and ***,the cellulose carbon aerogel@reduced graphene oxide aerogels(CCA@rGO)are prepared by vacuum impregnation,freeze-drying followed by thermal annealing,and finally,the CCA@rGO/polydimethylsiloxane(PdMS)EMI shielding composites are prepared by backfilling with *** to skin-core structure of CCA@rGO,the complete three-dimensional(3d)double-layer con-ductive network can be successfully *** the loading of CCA@rGO is 3.05 wt%,CCA@rGO/PdMS EMI shielding composites have an excellent EMI shielding effectiveness(EMI SE)of 51 dB,which is 3.9 times higher than that of the co-blended CCA/rGO/PdMS EMI shielding composites(13 dB)with the same loading of *** this time,the CCA@rGO/PdMS EMI shielding composites have excellent thermal stability(T_(HRI) of 178.3℃)and good thermal conductivity coefficient(λ of 0.65 W m^(-1) K^(-1)).Excellent comprehensive performance makes CCA@rGO/PdMS EMI shielding composites great prospect for applications in lightweight,flexible EMI shielding composites.

关键词： Polydimethylsiloxane Electromagnetic interference shielding Cellulose carbon aerogel Reduced graphene oxide

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