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四万年来青藏高原的气候变迁

第四纪研究 1990年第1期10卷 21-31页

作者：陈克造 J.M.Bowler k.kelts 中国科学院青海盐湖研究所澳大利亚堪培拉国立大学瑞士联邦苏黎世理工大学

内陆湖泊,特别是那些大型的淡水湖和盐湖,在漫长的演变历史长河中,对气候环境的反映是相当敏感的。巨厚的沉积物,记录了古气候变迁的丰富信息。盐湖的研究表明,40000年来的重大气候事件,在世界屋脊——青藏高原内部同样有明显的反映。

关键词：气候变化干盐湖蒸发岩

美国怀俄明州拉那依段岩相及碳氧同位素地球化学特征

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地质科学 1984年第3期 253-261+351页

作者：赵霞飞,J.Mackenzie,k.kelts 成都地质学院 Geologische Institut ETH-Z Zürich Switzerland Geologische Institut ETH-Z Zürich Switzerland

1980年6月,本文作者之一的***曾去美国参加由经济古生物学者和矿物学者协会组织的地质旅行。该行主要是观察和研究怀俄明州西南始新统绿河组的沉积环境。对此次旅行中带回瑞士苏黎世联邦理工学院地质研究所的样品,曾作了切片、X-射线衍... 详细信息

1980年6月,本文作者之一的***曾去美国参加由经济古生物学者和矿物学者协会组织的地质旅行。该行主要是观察和研究怀俄明州西南始新统绿河组的沉积环境。对此次旅行中带回瑞士苏黎世联邦理工学院地质研究所的样品,曾作了切片、X-射线衍射和碳氧同位素分析。其目的在于从同位素地球化学方面研究戈秀特湖(Lake Gosiute)的特征。众所周知,对怀俄明州始新统绿河组沉积条件的研究,自Bradley(1926,1948)的

关键词：怀俄明州纹层绿河组细层沉积相岩相碳酸盐矿物地球化学特征氧同位素美利坚合众国北美洲美国

Palaeomagnetic record from RH lacustrine core in Zoig■ Basin of Tibetan Plateau

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Science China Chemistry 1995年第12期38卷 1513-1521页

作者：陈发虎王苏民李吉均施雅凤李世杰曹继秀张宇田王云飞 k.kelts Department of Geography Lanzhou UniversityLanzhou 730000China Nanjing Institute of Lake and Geography Chinese Academy of SciencesNanjing 210000 Lanzhou Institute of Glaciology and Cryology Chinese Academy of SciencesLanzhou 730000 Lake Reserch Centre University of MinnesotaUSA

RH core,located in the Zoigê Basin of Eastern Tibetan Plateau,is a quite good *** is 120.40m *** geomagnetic excursions or events were recorded in the core during Brunhesnormal epoch based on measurement results of the remnant magnetization of small interval core samples(10cminterval)under series AF demagnetization,and organic carbon-14 and AMS *** excursions recorded bythe core can be correlated with those found in other regions in the *** are the most detailed recordin lacustrine deposit in China.B/M boundary in the core is at the depth of *** can be calculatedfrom the depositional rate of 0.13mm/a that the bottom age of the core is 825 ka *** excursion ages inBrunhes and their correlation with those found in other regions are discussed.

关键词： Tibetan Plateau lacustrine core magnetostratigraphy geomagnetic excursions.

白垩纪末期生物大批死亡引起的环境变化及其演化意义

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吉林大学学报（地球科学版） 1982年第1期25卷 1-14页

作者：许靖华何起祥 J.A.Mckenzie H.Weissert k.Perch-Nielsen H.Oberhnsli k.kelts J.LaBrecque U.krhenbühl S.F.Percival R.Wright R.Z.Poore A.M.Gombos k.Pisciotto A.M.karpoff N.Petersen P.Tucker M.F.Carman E.Schreiber

DSDP 524区中生代最晚期和第三纪最早期的沉积物中,保存着白垩纪末期环境变化和生物演化的详细纪录。我们对该孔进行了加密取样,样品间距大致相当于100年或1000年的时间间隔,同时对样品进行了碳酸盐含量、微量元素成分及碳氧同位素分析... 详细信息

DSDP 524区中生代最晚期和第三纪最早期的沉积物中,保存着白垩纪末期环境变化和生物演化的详细纪录。我们对该孔进行了加密取样,样品间距大致相当于100年或1000年的时间间隔,同时对样品进行了碳酸盐含量、微量元素成分及碳氧同位素分析。我们所得到的数据可以解释为白垩纪末期生物大批死亡的结果,当时大量远洋地区的生物扫地以尽。养料锐减导致部分从河流带来的溶解CO_2转移到大气圈,致使在长达40,000年的时间内,空气中的CO_2剧增。由此产生的温室效应就是氧同位素所揭示的温度升高的原因。第三纪最早期沉积物中,包括来自“白垩纪生物群”中的化石,有的已经过再沉积作用,有的则是这场灾难的最后幸存者。我们的资料表明,大量远洋生物的灭绝是在第三纪最早期的不利环境中发生的。而这种异常的环境则是生物大批死亡的结果,且持续有几千年之久。恐龙就是因为温度灾难性升高产生的热异常而灭绝的。大洋中生物大批灭绝的原因,与巨大的天外星体的陨落有关,界线附近的铱异常即其标志,我们的资料与许靖华不久前发表的彗星冲击说是不抵触的。

关键词：环境变化碳氧同位素碳同位素碳酸盐含量许靖华大气圈半深海沉积过渡带铱异常有孔虫化石

Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 193-208页

作者： k.MUHAMMAD M.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of Mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(MHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in MATHEMATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词：

Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice

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Neural Regeneration Research 2025年第8期20卷 2348-2360页

作者： Mohamed Aghyad Al kabbani Christoph köhler Hans Zempel Institute of Human Genetics Faculty of Medicine and University Hospital CologneUniversity of CologneCologneGermany Center for Molecular Medicine Cologne(CMMC) University of CologneCologneGermany Center Anatomy Department ⅡMedical FacultyUniversity of CologneCologneGermany

TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the *** is missorted and aggregated in an array of diseases known as *** are essential for neuronal function and regulated via a complex set of post-translational modifications,changes of which affect microtubule stability and dynamics,microtubule interaction with other proteins and cellular structures,and mediate recruitment of microtubule-severing *** impairment of microtubule dynamics causes neuronal dysfunction,we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule *** therefore aimed to study the effects of a disease-causing mutation of TAU(P301L)on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics,to assess whether P301L-TAU causes stability-changing modifications to *** investigate TAU localization,phosphorylation,and effects on tubulin post-translational modifications,we expressed wild-type or P301L-TAU in human MAPT-kO induced pluripotent stem cell-derived neurons(i Neurons)and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU(p R5 mice).Human neurons expressing the longest TAU isoform(2N4R)with the P301L mutation showed increased TAU phosphorylation at the AT8,but not the p-Ser-262 epitope,and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons.P301L-TAU showed pronounced somatodendritic presence,but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU.P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation,but reduced acetylation,of microtubules compared with non-transgenic *** sum,P301L-TAU results in changes in micr

关键词： human induced pluripotent stem cell microtubules P301L pR5 mice TAU tauopathy tubulin code

淡水湖泊沉积物中有机硫的固定作用及C/S比值的意义

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地质地球化学 1993年第6期21卷 40-46页

作者： A.J.Losher k.R.kelts 韦朝阳中科院地理研究所

本文通过取自阿尔卑斯山边缘湖泊(苏黎世湖和日内瓦湖)的两个沉积柱的对比分析,阐明了硫在淡水沉积物中的固着途径。尽管这两个湖泊中湖水硫酸盐浓度相差三倍以上,但固定在沉积物中的硫含量是相等的。沉积硫的最大浓度达1％(干重),与现... 详细信息

本文通过取自阿尔卑斯山边缘湖泊(苏黎世湖和日内瓦湖)的两个沉积柱的对比分析,阐明了硫在淡水沉积物中的固着途径。尽管这两个湖泊中湖水硫酸盐浓度相差三倍以上,但固定在沉积物中的硫含量是相等的。沉积硫的最大浓度达1％(干重),与现代近海岸海相沉积物的硫含量相似。也表现在C_(有机)/S_总比值上,该比值较低,为2.5～8。对硫储体的分析表明,有机硫化合物是沉积硫的主要成分,在苏黎世湖和日内瓦湖中分别占总硫的80％和60％。最大的单个硫储体是硫酯,占总沉积硫的40％～60％。在沉积物氧化-还原转换带中,由于边界层微生物的作用而形成了大量的有机硫化合物。这可能意味着硫在次氧化带中的快速循环。由于水体中SO_4^(2-)浓度低,故硫酸盐还原带很厚。硫酸盐还原带同硫化物氧化微生物群落[如贝氏硫细菌(Beggiatoa)]的活动可能会导致沉积物-水界面附近的硫储体的彻底再循环。循环过程中带入的还原硫对沉积黄铁矿的形成不起作用,因此这些沉积物中的C_(有机)/S_(黄铁矿)比值较高。如果在成岩作用后期有机结合硫未能完全转换进入到黄铁矿中,C_(有机)/S_(黄铁矿)比值则可作为古沉积环境盐度的一个灵敏指标。

关键词：淡水湖沉积物有机硫沉积作用

Human endogenous retrovirus type-W and multiple sclerosis–related smoldering neuroinflammation

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Neural Regeneration Research 2025年第3期20卷 813-814页

作者： Joel Gruchot Laura Reiche Andrew Chan Robert Hoepner Patrick küry Department of Neurology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neurology InselspitalBern University Hospital and University of BernBernSwitzerland

Introduction to human endogenous retrovirus type-W(HERV-W): Genomic inheritance from the past includes retroviral sequences that have been stably incorporated into our genomes and account for up to 8% of human DNA.

关键词： endogenous inflammation Human

Nucleoside modified mRNA-lipid nanoparticles as a new delivery platform for the repair of the injured spinal cord

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Neural Regeneration Research 2025年第8期20卷 2311-2312页

作者： krisztián Pajer Tamás Bellák Antal Nógrádi Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary

Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular *** the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(khyeam et al.,2021).

关键词： injured capacity modified