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Pre-mRNA modifications and their role in nuclear processing

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Frontiers of Electrical and Electronic Engineering in China 2018年第3期6卷 210-227页

作者： nicole m martinez Wendy V Gilbert Department of molecular Biophysics ＆ Biochemistry Yale UniversityNew HavenCT 06520USA

Background： Cellular non-coding RNAs are extensively modified post-transcriptionally, with more than 100 chemically distinct nucleotides identified to date. In the past five years, new sequencing based methods have revealed widespread decoration of eukaryotic messenger RNA with diverse RNA modifications whose functions in mRNA metabolism are only beginning to be known. Results： Since most of the identified mRNA modifying enzymes are present in the nucleus, these modifications have the potential to function in nuclear pre-mRNA processing including alternative splicing. Here we review recent progress towards illuminating the role of pre-mRNA modifications in splicing and highlight key areas for future investigation in this rapidly growing field. Conclusions： Future studies to identify which modifications are added to nascent pre-mRNA and to interrogate the direct effects of individual modifications are likely to reveal new mechanisms by which nuclear pre-mRNA processing is regulated.

关键词： mRNA modification pre-mRNA modification splicing RNA-modifying enzymes

Leaf/shoot level ecophysiology in two broadleaf and two needle-leaf species under representative cloud regimes at alpine treeline

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Journal of Plant Ecology 2016年第6期9卷 762-772页

作者： Adriana Sanchez nicole m.Hughes William K.Smith Programa de Biología Universidad del RosarioCarrera 24 No.63C-69BogotáDC 110011Colombia Department of Biology Wake Forest University136 Winston HallWinston-SalemNC 27106USA Department of Biology High Point UniversityUniversity Station 3591High PointNC 27262USA

Aims The effects of clouds are now recognized as critically important to the understanding of climate change impacts on ***,few studies have focused specifically on the ecophysiological responses of plants to *** continental mountain ranges are characterized by common convective cloud formation in the afternoons,yet little is known regarding this influence on plant water and carbon *** we compare the ecophysiology of two contrasting,yet ubiquitous growth forms,needle-leaf and broadleaf,under representative cloud regimes of the Snowy Range,medicine Bow mountains,southeastern Wyoming,*** Photosynthetic gas exchange,water use efficiency,xylem water potentials and micrometeorological data were measured on representative clear,overcast and partly cloudy days during the summers of 2012 and 2013 for two indigenous broadleaf(Caltha leptosepala and Arnica parryi)and two needle-leaf species(Picea engelmannii and Abies lasiocarpa)that co-occur *** Findings Reductions in sunlight with cloud cover resulted in more dramatic declines in photosynthesis for the two broadleaf species(ca.50-70%reduction)versus the two conifers(no significant difference).In addition,the presence of clouds corresponded with lower leaf conductance,transpiration and plant water status in all ***,the more constant photosynthesis in conifers under all cloud conditions,coupled with reduced transpiration,resulted in greater water use efficiency(ca.25%higher)than the broadleaf *** differences appear to implicate the potential importance of natural cloud patterns in the adaptive ecophysiology of these two contrasting,but common,plant growth forms.

关键词： gas exchange light response curves water use efficiency xylem water potential

The emerging role and targetability of the TCA cycle in cancer metabolism

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Protein & Cell 2018年第2期9卷 216-237页

作者： nicole m. Anderson Patrick mucka Joseph G. Kern Hui Feng Abramson Family Cancer Research Institute University of Pennsylvania Philadelphia PA 19104-6160 USA Perelman School of medicine at the University of Pennsylvania Philadelphia PA 19104 USA Departments of Pharmacology and medicine The Center for Cancer Research Section of Hematology and Medical Oncology Boston University School of Medicine Boston MA 02118 USA Program in Biomedical Sciences Boston University School of Medicine Boston MA 02118 USA

The tricarboxylic acid （TCA） cycle is a central route for oxidative phosphorylation in cells, and fulfills their bioenergetic, biosynthetic, and redox balance require- ments. Despite early dogma that cancer cells bypass the TCA cycle and primarily utilize aerobic glycolysis, emerging evidence demonstrates that certain cancer cells, especially those with deregulated oncogene and tumor suppressor expression, rely heavily on the TCA cycle for energy production and macromolecule synthesis. As the field progresses, the importance of aberrant TCA cycle function in tumorigenesis and the potentials of applying small molecule inhibitors to perturb the enhanced cycle function for cancer treatment start to evolve. In this review, we summarize current knowledge about the fuels feeding the cycle, effects of oncogenes and tumor suppressors on fuel and cycle usage, common genetic alterations and deregulation of cycle enzymes, and potential therapeutic opportunities for targeting the TCA cycle in cancer cells. With the application of advanced technology and in vivo model organism studies, it is our hope that studies of this previously overlooked biochemical hub will provide fresh insights into cancer metabolism and tumorigenesis, subsequently revealing vulnerabilities for thera- peutic interventions in various cancer types.

关键词： glutaminolysis the TCA cycle cancer metabolism glycolysis

长白山天池火山千年大喷发岩浆含水量研究——熔融包裹体含水量的红外光谱测试

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岩石学报 2006年第6期22卷 1465-1472页

作者：李霓 nicole méTRICH 樊祺诚中国地震局地质研究所 Laboratoire Pierre Süe CEA-CNRSSaclay91191 Gif sur YvetteFrance

长白山天池火山在公元一千年左右曾发生过大规模喷发,其产物为大面积分布的灰白色碱流质浮岩和碎屑流,在其斑晶矿物橄榄石、钙铁辉石和碱性长石中均可见到熔融包裹体。在最主要的斑晶矿物——碱性长石中含有数量众多且个体也较大的熔融... 详细信息

长白山天池火山在公元一千年左右曾发生过大规模喷发,其产物为大面积分布的灰白色碱流质浮岩和碎屑流,在其斑晶矿物橄榄石、钙铁辉石和碱性长石中均可见到熔融包裹体。在最主要的斑晶矿物——碱性长石中含有数量众多且个体也较大的熔融包裹体,多数含有一个以上的气泡,其中部分含有子晶,根据形貌特征的不同可分为截然不同的两组包裹体。这些熔融包裹体带有大量喷发前地下岩浆的信息,成为研究地下深部的岩浆在复杂的溢流-爆炸喷发中所发生变化的最好媒介,也是本文的研究对象,通过其中挥发份尤其是水的含量,可以推知天池火山发生大喷发的原因。经nicolet magna-IR 550红外光谱仪测定,这些熔融包裹体的含水量较高,达1．6%～3．6%,为当时天池火山发生了巨大规模爆炸喷发的原因提供了强有力的证据。但目前红外光谱仪的应用范围还比较有限,有待今后拓宽其应用领域。

关键词：长白山天池火山千年大喷发碱性长石熔融包裹体红外光谱测试

Land tenure and landscape change:a comparison of public-private lands in the southern High Plains

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Ecological Processes 2016年第1期5卷 139-152页

作者： Todd D.Fagin Jacqueline m.Vadjunec nicole m.Colston Kathyrn Wenger Amy Graham Oklahoma Biological Survey University of Oklahoma111 E.Chesapeake StNorman 73019OKUSA Department of Geography Oklahoma State University337 Murray HallStillwater 74078OKUSA

Introduction:Long-term drought in the southern Great Plains increases the vulnerability of coupled human-environment systems at a variety of *** better understandings of the dynamics at regional scales will become increasingly important as long-established land-use regimes break down in the face of climate change,resource depletion,and evolving *** demonstrate differential vulnerability during drought periods,this study hypothesized that observed increases in woody vegetation in grasslands would vary across land-tenure *** argue that differences in State Trust Land governance,in part,lead to differential land management practices that contribute to landscape ***:The study area encompasses adjacent counties,Cimarron County in Oklahoma and Union County in New mexico,with similar climate variability and agricultural *** analyzed National Land Cover Database(NLCD)land-cover maps from 1992 and 2011 to assess changes in landscape composition and structure between 1992 and ***:During both years under consideration,each county in the study region,across various land-tenure regimes,was dominated by herbaceous ***,there were changes in both composition and structure across the whole study area,in particular losses of herbaceous vegetation and increases in woody *** greatest gains in woody vegetation occurred in State Trust Lands of Cimarron ***,the data suggest a fragmentation of herbaceous vegetation and a coalescing of shrubland ***:Research about the influence of land tenure on land management decisions,specifically the role of State Trust Land leases in overgrazing,informs the broader context of drought management in the southern Great *** include continued research to highlight the specific mechanisms of land-tenure governance that drive landscape change.

关键词： Drought Land tenure Agriculture Landscape composition Landscape structure Southern Great Plains Grasslands Socio-ecological vulnerability National Land Cover Database(NLCD)

Inventory of the Thermo-Physiological Behavior of Fabrics—A Review

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Journal of Textile Science and Technology 2023年第2期9卷 127-150页

作者： nicole mölders Department of Atmospheric Sciences University of Alaska Fairbanks Fairbanks USA Geophysical Institute University of Alaska Fairbanks Fairbanks USA

A comprehensive literature review was performed to create an inventory of thermal-physiological quantities for fabrics from different fiber materials, material blends, and fabric structures. The goal was to derive over-arching concepts that cannot be seen by the individual studies alone. Equations of best fits suggest non-linear changes for fabric thickness, thermal and water-vapor resistance with changes in material blend ratio. Air permeability decreases with increasing fabric density and fabric weight wherein the degree of decrease differs among fabric materials, blend ratio, and fabric structure. Water-vapor transmission rates strongly depend on fabric thickness, material, and blend, but marginally depend on fabric structure as long as the fabric and material thickness remain the same.

关键词： Thermal Resistance of Fabrics Thermal Conductivity of Fabrics Water-Vapor Resistance of Fabrics Water-Vapor Transmission Rate Inventory of Thermal-Physiological Characteristics of Fabrics Energetics of Fabrics

Telomeres:Linking stress and survival,ecology and evolution

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Current Zoology 2010年第6期56卷 714-727页

作者： mark F.HAUSSmANN nicole m.mARCHETTO Department of Biology Bucknell University

Telomeres are protective structures at the ends of eukaryotic chromosomes. The loss of telomeres through cell division and oxidative stress is related to cellular aging, organismal growth and disease. In this way, telomeres link molecular and cellular mechanisms with organismal processes, and may explain variation in a number of important life-history traits. Here, we discuss how telomere biology relates to the study of physiological ecology and life history evolution. We emphasize current knowledge on how telomeres may relate to growth, survival and lifespan in natural populations. We finish by examining interest- ing new connections between telomeres and the glucocorticoid stress response. Glucocorticoids are often employed as indices of physiological condition, and there is evidence that the glucocorticoid stress response is adaptive. We suggest that one way that glucocorticoids impact organismal survival is through elevated oxidative stress and telomere loss. Future work needs to establish and explore the link between the glucocorticoid stress response and telomere shortening in natural populations. If a link is found, it provides an explanatory mechanism by which environmental perturbation impacts life history trajectories [Current Zoology 56 （6）： 714-727, 2010].

关键词： Corticosterone Stress Survival Telomeres

长白山天池火山全新世3期浮岩长石斑晶中熔体包裹体高温热台实验研究

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地震地质 2007年第3期29卷 459-469页

作者：李霓 nicole métrich 樊祺诚中国地震局地质研究所 Laboratoire Pierre Süe CEA-CNRSSaclay91190France

长白山天池火山在全新世曾多次喷发,以往研究结果基本上认定至少有3期喷发物:距今约5,000a前淡黄色碱流质浮岩、距今约1,000a前灰白色碱流质浮岩和碎屑流以及距今约300a的黑色粗面质浮岩和熔结凝灰岩。喷发物斑晶矿物中含有众多熔体包裹... 详细信息

长白山天池火山在全新世曾多次喷发,以往研究结果基本上认定至少有3期喷发物:距今约5,000a前淡黄色碱流质浮岩、距今约1,000a前灰白色碱流质浮岩和碎屑流以及距今约300a的黑色粗面质浮岩和熔结凝灰岩。喷发物斑晶矿物中含有众多熔体包裹体,形貌特征各有不同。经Leitz1350高温热台对天池火山全新世3期喷发物长石中熔体包裹体的均一法测温实验,结果表明第1,3喷发期的岩浆温度相差不大,而千年大喷发期较为复杂,揭示当时有2个不同温度段的熔体存在,为大喷发可能由2种岩浆注入和混合而触发的论点提供了线索。实验还证实,个体小的熔体包裹体易于均一,而个体较大的、尤其是含有大量子晶的熔体包裹体则很难均一;均一温度与熔体包裹体大小、何时从较快升温速率变为较慢升温速率、是否为初次升温时测量得出有关。同一颗熔体包裹体多次数升温至均一,每次得到的均一温度不同,而且每升温一次得到的均一温度均比前一次高,证实了均一过程中的确有H扩散的现象。

关键词：长白山天池火山碱性长石熔体包裹体高温热台均一温度

Volatile variation （H2O, Cl, S） of melt inclusion in phenocryst from Tianchi volcano eruptions （China/North Korea） in Holocene

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Volatile variation （H2O, Cl, S） of melt inclusion in pheno...