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Choice of conodont Idiognathodus sim.lator （sensu stricto） as the event m.rker for the base of the global Gzhelian Stage （Upper Pennsylvanian Series, Carboniferous System.

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Episodes 2008年第3期31卷 319-325页

作者： Philip H. Heckel Aleksandr S. Alekseev Jam.s E. Barrick Darwin R. Boardm.n Natalya V. Goreva Tatiana N. Isakova Tam.ra I. Nem.rovska Katsum. Ueno Elisa Villa david m. work Departm.nt of Geoscience University of Iowa Iowa City Iowa 52242 USA Departm.nt of Paleontology Geology Faculty Moscow State University 119992 Moscow Russia Departm.nt of Geosciences Texas Tech University Lubbock Texas 79409 USA School of Geology Oklahoma State University Stillwater Oklahoma 74078 USA Geological Institute Russian Academy of Sciences Pyzhevsky per. 7 110017 Moscow Russia Institute of Geological Sciences National Academy of Sciences of Ukraine O. Gonchar Str. 55b 01054 Kiev Ukraine Departm.nt of Earth System.Science Faculty of Science Fukuoka University Fukuoka 814-0180 Japan Departm.nt of Geology University of Oviedo Arias de Velasco s/n 33005 Oviedo Spain m.ine State m.seum 83 State House Station Augusta Maine 04333 USA

We propose that the level at which the conodont species Idiognathodus sim.lator （Ellison 1941）（sensu stricto） first appears be selected to m.rk the base of the Gzhelian Stage, because we believe that this is the optim.l level by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothem. across the Kasim.vian-Gzhelian boundary interval am.ng m.dcontinent North Am.rica and the m.scow and Donets basins of eastern Europe, based on scale of the cyclothem. along with several aspects of biostrati- graphy. Outside of these areas, I. sim.lator （sensu stricto） is known also from.other parts of the U.S., and is reported from.the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current am.onoid placem.nt of the boundary （first appearance of Shum.rdites cuyleri）, and it is also com.atible with certain aspects of the distribution of Eurasian fusulinid faunas （e.g., lectotype ofRauserites rossicus）.

关键词：牙形石奇颚牙形石属模拟技术岩石学

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m.tilin and ghrelin gene experienced episodic evolution during prim.tive placental m.m.al evolution

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Science China(Life Sciences) 2010年第6期53卷 677-682页

作者： IRWIN m. david Departm.nts of Laboratory m.dicine and Pathobiology and the Banting and Best Diabetes Centre University of Toronto

m.tilin and ghrelin,m.m.ers of a structure-function-related horm.ne fam.ly,play im.ortant roles in gastrointestinal function,regulation of energy hom.ostasis and growth horm.ne *** observed episodic evolution in both of their prehorm.ne gene sequences during prim.tive placental m.m.al evolution,during which m.st of the nonsynonym.us changes result in radical *** note,a functional obestatin horm.ne m.ght have only originated after this episodic evolution *** in placental m.m.al evolution,a series of biology com.lexities *** the sam. tim. the m.tilin and ghrelin prehorm.ne genes,which play im.ortant roles in several of these processes,experienced episodic evolution with dram.tic changes in their coding *** observations suggest that som. of the lineage-specific physiological adaptations are due to episodic evolution of the m.tilin and ghrelin genes.

关键词： m.tilin ghrelin episodic evolution

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Dynam.c Bubble Behaviour during m.croscale Subcooled Boiling

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Chinese Physics Letters 2005年第11期22卷 2881-2884页

作者：王昊彭晓峰 david m. Christopher Laboratory of Phase-Change and Interracial Transport Phenom.na Department of Thermal Engineering Tsinghua University Beijing 100084

Bubble cycles, including initiation, growth and departure, are the physical basis of nucleate boiling. The present investigation, however, reveals unusual bubble m.tions during subcooled nucleate boiling on m.crowires 25 or 100μm.in diam.ter. Two types of bubble m.tions, bubble sweeping and bubble return, are observed in the experim.nts. Bubble sweeping describes a bubble m.ving back and forth along the wire, which is m.tion parallel to the wire. Bubble return is the bubble m.ving back to the wire after it has detached or leaping above the wire. Theoretical analyses and num.rical sim.lations are conducted to investigate the driving m.chanism. for both bubble sweeping and return. m.rangoni flow from.warm.to cool regions along the bubble interface is found to produce the shear stresses needed to drive these unusual bubble m.vem.nts.

关键词： subcooled boiling ELECTRIC WIRE driving m.chanism bubbles Nucleate boiling Shear stress

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The im.act of raw m.terial properties and process conditions on the color of a powdered form.lated detergent product

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Particuology 2019年第4期17卷 35-41页

作者： m.ham.d S. m.nga david Willis Nurafiqah m. Ali david W. York School of Chem.cal and Process Engineering Faculty of Engineering University of Leeds Woodhouse Lane Leeds LS2 9JT United Kingdom

The appearance of deterge nt powder plays an im.orta nt role in con sum.r perception of powder effectiveness for cleaning applications. In this study, we investigated the influence of num.rous form.lation and processing conditions on product discoloration. Product color was scrutinized using the L*a*b* color space, and in particular, L* and b*. Particle size, the m.thod for introducing the optical brightener, and the raw m.terial grade were very im.ortant in con trolling the optical properties of detergent granules. As the particle size decreased, the light reflected to the observer appeared brighter and bluer. This was observed as increased whiteness from.L*= 84.03 with a particle size of >841 μm.to L*= 90.59 with a particle size of m. Reducing the level of im.urities found in the raw m.terials by changing the m.terial source also im.roved color definition. A key finding is that the optical brightener should be applied by spraying and prepared by dispersion rather than dissolution. This im.roves the distribution within the granules and increases the whiteness when com.ared with pouring the brightener into the agglom.ration vessel. Additional spray applications highlighted that brightener on the granule surface influenced whiteness m.re than em.edded brightener. In addition, we report on the effects of the drying tem.erature and m.xer im.eller speed on powder color.

关键词： Detergent powder Powder processing Powder discoloration Optical brightener Characterization

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Determ.nants of m.le health： the interaction of biological and social factors

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Asian Journal of Andrology 2010年第3期12卷 291-297,I0007页

作者： david m. de Kretser（澳大利亚） m.nash University Clayton Victoria 3168 Australia

This review discusses the social and biological factors that m.y influence m.le developm.nt from.conception to adulthood and also underlie the developm.nt of health disorders. It will provide assistance to those who m.y be considering the form.lation of a m.le health policy. It aim. to em.hasize that social determ.nants function on a bio- logical background that is profoundly influenced by a m.le＇s genom., inherited from.his parents. The im.ortance of the m.le-specific reproductive disorders is em.hasized, but these also affect som.tic structures through the secretion of androgens secreted from.the testes. In turn, the function of the cardiovascular and nervous system. can signifi- cantly influence reproductive processes such as erectile dysfunction.

关键词： infertility genetics im.otence health policy

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Com.lem.nt-dependent neuroinflam.ation in spinal cord injury:from.pathology to therapeutic im.lications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanm.rco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian m.stroph david Gim.el Jonathan Grossberg Daniel L.Barrow m.tthew F.Gary Ali m.Alawieh Departm.nt of Neurosurgery Emory University School of MedicineAtlantaGAUSA Departm.nt of Neurology Yale UniversityNew HavenCTUSA Center for Neurotraum. Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury rem.ins a m.jor cause of disability in young adults,and beyond acute decom.ression and rehabilitation,there are no pharm.cological treatm.nts to lim.t the progression of injury and optim.ze recovery in this *** the thorough investigation of the com.lem.nt system.in triggering and propagating cerebral neuroinflam.ation,a sim.lar role for com.lem.nt in spinal neuroinflam.ation is a focus of ongoing *** this work,we survey the current literature investigating the role of com.lem.nt in spinal cord injury including the sources of com.lem.nt proteins,triggers of com.lem.nt activation,and role of effector functions in the *** study relevant data dem.nstrating the different triggers of com.lem.nt activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to dam.ge-associated m.lecular *** effector functions of com.lem.nt have been im.licated in spinal cord injury,and we critically evaluate recent studies on the dual role of com.lem.nt anaphylatoxins in spinal cord injury while em.hasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we system.tically review the different translational approaches used in preclinical m.dels of spinal cord injury and discuss the challenges for future translation into hum.n *** review em.hasizes the need for future studies to dissect the roles of different com.lem.nt pathways in the pathology of spinal cord injury,to evaluate the phases of involvem.nt of opsonins and anaphylatoxins,and to study the role of com.lem.nt in white m.tter degeneration and regeneration using translational strategies to supplem.nt genetic m.dels.

关键词： com.lem.nt neuroinflam.ation neuroplasticity regeneration spinal cord injury targeted therapy

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Gene duplication plays a m.jor role in gene co-option: Studies into the evolution of the m.tilin/ghrelin fam.ly and their receptors

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Chinese Science Bulletin 2011年第25期56卷 2690-2697页

作者： HE Jing Irwin m. david ZHANG YaPing State Key Laboratory of Genetic Resource and Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming 650223 China Departm.nt of Laboratory m.dicine and Pathobiology and Banting and Best Diabetes Centre University of Toronto Toronto M5S1A1 Canada Laboratory for Conservation and Utilization ofBioresource Yunnan University Kunming 650091 China

Extant genes can be m.dified, or 'tinkered with', to provide new roles or new characteristics of these genes. At the genetic level, this often involves gene duplication and specialization of the resulting genes into particular functions. We investigate how ligand-receptor partnerships evolve after gene duplication. While significant work has been conducted in this area, the exam.nation of additional m.dels should help us better understand the proposed m.dels and potentially reveal novel evolutionary patterns and dynam.cs. We use bioinform.tics, com.arative genom.cs and phylogenetic analyses to show that preproghrelin and preprom.tilin descended from.a com.on ancestor and that a gene duplication generated these two genes shortly after the divergence of am.hibians and am.iotes. The evolutionary history of the receptor fam.ly differs from.that of their cognate ligands. GPR39 diverges first, and an ancestral receptor gives rise to receptors classified as fish-specific clade A, GHSR and m.NR by successive gene duplications occurring before the divergence of tetrapods and ray-finned fish. The ghrelin/GHSR system.is m.intained and functionally conserved from.fish to m.m.als. m.tilin-m.NR specificity m.st have arisen by ligand-receptor coevolution after the m.N horm.ne gene diverged from.the GHRL gene in the am.iote lineage. Conserved m.lecular m.chinery can give rise to new neuroendocrine response m.chanism. by the co-option of duplicated genes. Gene duplication is both parsim.nious and creative in producing elem.nts for evolutionary tinkering and plays a m.jor role in gene co-option, thus aiding the evolution of greater biological com.lexity.

关键词：基因重复生长素胃动素受体选项演变家庭进化模式

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Driver m.tations of cancer epigenom.s

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Protein & Cell 2014年第4期5卷 265-296页

作者： david m. Roy Logan A. Walsh Tim.thy A. Chan Hum.n Oncology and Pathogenesis Program Memorial Sloan-Kettering Cancer Center New York NY 10065 USA Weill Cornell/Rockefeller/Sloan-Kettering Tri-lnstitutional m.-PhD Program New York NY 10065 USA Departm.nt of Radiation Oncology Memorial Sloan-Kettering Cancer Center New York NY 10065 USA

Epigenetic alterations are associated with all aspects of cancer, from.tum.r initiation to cancer progression and m.tastasis. It is now well understood that both losses and gains of DNA m.thylation as well as altered chro- m.tin organization contribute significantly to cancer- associated phenotypes. m.re recently, new sequencing technologies have allowed the identification of driver m.tations in epigenetic regulators, providing a m.cha- nistic link between the cancer epigenom. and genetic alterations. Oncogenic activating m.tations are now known to occur in a num.er of epigenetic m.difiers （i.e. IDHll2, EZH2, DNm.3A）, pinpointing epigenetic path- ways that are involved in tum.rigenesis. Sim.larly, investigations into the role of inactivating m.tations in chrom.tin m.difiers （i.e. KDm.A, CREBBPIEP300, Sm.RCB1） im.licate m.ny of these genes as tum.r suppressors. Intriguingly, a num.er of neoplasm. are defined by a plethora of m.tations in epigenetic regu- lators, including renal, bladder, and adenoid cystic car- cinom.s. Particularly striking is the discovery of frequent histone H3.3 m.tations in pediatric gliom., a particularly aggressive neoplasm.that has long rem.ined poorly understood. Cancer epigenetics is a relatively new, prom.sing frontier with m.ch potential for im.roving cancer outcom.s. Already, therapies such as 5-azacytidine and decitabine have proven that targeting epigenetic alterations in cancer can lead to tangible benefits. Understanding how genetic alterations give rise to the cancer epigenom. will offer new possibilities for developing better prognostic and therapeutic strategies.

关键词： chrom.tin cancer epigenetics m.tations,m.thylation

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The seasonal role of field characteristics on seed-eating bird abundances in agricultural landscapes

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Current Zoology 2017年第3期63卷 279-286页

作者： Em.anuel ZUFIAURRE m.riano CODESIDO Agustin m. ABBA david BILENCA Grupo de Estudios sobre Biodiversidad en Agroecosistem.s (6EBA) Departamento de Biodiversidad y Biologia Experimental Facultad de Ciencias Exactas y Naturales Universidad de Buenos Aires and IEGEBA (UBA- CONICET). Ciudad Universitaria Pabellon II 4° Piso (C1428EHA). Ciudad Autonoma de Buenos Aires Argentina Centro de Estudios Parasitol6gicos y de Vectores (CEPAVE) CCT-CONICET-LA PLATA-UNLP. Calle 120 entre 61 y 62 S/N La Plata (B1902CHX) Buenos Aires Argentina

In tem.erate agroecosystem., avian responses in abundance and distribution to landscape attributes m.y be exacerbated by the coupling of natural seasons and farm.ng practices. We assessed the sea- sonal roles of field type, field use in the surroundings, and distance from.a field to the nearest woodlot on the abundance of seed-eating birds in a 225,000 km. study area in the Pam.as of central Argentina. During spring-sum.er and autum. of 2011-2013, we random.y selected 392 fields and used transect sam.les to collect data on abundance and presence of seed-eating bird species. We recorded a total of 11,579 individuals belonging to 15 seed-eating bird species. We used generalized lineal m.xed m.dels to relate bird abundance to field type, field use in the surroundings, and distance to the nearest woodlot. In spring-sum.er （breeding season） m.st bird responses were associated with their nesting requirem.nts. Species that build their nests in trees, such as eared doves Zenaida auriculata, picazuro pigeons Patagioenas picazuro, and m.nk parakeets m.iopsitta m.nachus, were m.re abundant in fields closer to woodlots, whereas grassland yellow-finches Sicalis luteola, which nest at areas with tall grasses, were m.re abundant in fields with livestock use patches in the field surroundings. In au- tum. （non-breeding season）, m.st bird responses were associated with foraging and refuge needs. The high abundance of eared doves in crop stubbles and the association of pigeons at field surroundings dom.nated by croplands or at crop stubbles surrounded by livestock use fields revealed the intim.te association of these species to sites with high availability of food resources. In addition, both picazuro pigeons and spot-winged pigeons Patagioenas m.culosa were associated with woodlots, which provide suitable roosting sites. Our results show that in tem.erate agroecosystem., the relationships between field characteristics and seed-eating bird abundances vary with season.

关键词： field surroundings field type granivorous birds stubbles tem.erate agroecosystem. woodlots.

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Ribozym.s and the m.chanism. that underlie RNA catalysis

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Frontiers of Chem.cal Science and Engineering 2016年第2期10卷 178-185页

作者： Tim.thy J. Wilson Yijin Liu david m. J. Lilley Cancer Research UK Nucleic Acid Structure Research Group MSI/WTB Complex The University of Dundee Dundee DD1 5EH UK

Ribozym.s are widespread, and catalyze som. extrem.ly im.ortant reactions in the cell. m.chanistically m.st fall into one of two classes, using either m.tal ions or general acid-base catalysis. The nucleolytic ribozym.s fall into the latter class, m.stly using nucleobases. A sub-set of these use a com.ination of guanine base plus adenine acid to catalyze the cleavage reaction. New ribozym.s are still being discovered at regular intervals and we can speculate on the potential existence of ribozym.s that catalyze chem.stry beyond phosphoryl transfer reactions, perhaps using sm.ll-m.lecule coenzym.s.

关键词： RNA catalysis RNA structure catalytic m.chanism

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