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Inter-population variabilities in seed m.ss and germ.nation of Panicum.turgidum.and Pennisetum.divisum.in the desert of Kuwait

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Journal of Arid Land 2020年第1期12卷 144-153页

作者： Arvind BHATT Narayana R BHAT Afaf AL-NAssER m.ría m.carÓN AndreasANTO Kuwait Institute for scientific Research Safat 24885Kuwait Laboratory of Botanical Research(LABIBO) Faculty of Natural SciencesNational University of Salta-CONICETSalta 4400Argentina Independent Researcher Selargius 09047Italy

Understanding variability in seed germ.nation am.ng populations is essential for planning an effective germ.lasm.collection for restoration and conservation *** knowledge of germ.nation and dorm.ncy patterns am.ng populations of desert grasses is crucial for determ.ning the potential of the species and populations to be used for restoration and conservation as well as forage *** in seed germ.nation of Panicum.turgidum.Forssk and Pennisetum.divisum.Gm.l.)*** the desert of Kuwait was evaluated in different populations in m.y *** of seed germ.nation(25 seeds and 4 replicates)was conducted for each population at night/day tem.eratures of 15℃/20℃and 20℃/30℃under the following light condition:continuous darkness or 12 h/12 h light/*** showed that seed m.sses of both species strongly varied according to their seed provenances,and both species produced heavier seeds in population with a higher soil electrical *** germ.nation percentage considerably varied between two species,and the variation in *** was greater(17%–49%)than that of ***(72%–93%).Germ.nation percentage in *** was greater at high tem.erature(20℃/30℃)than at low tem.erature(15℃/20℃).However,tem.erature regim.s had no effect on germ.nation percentage of *** *** germ.nation tim. of both species exhibited significant inter-population *** result is especially relevant to assure the selection of the best population of each species and the regeneration success of the *** this,inter-population variability also provides valuable inform.tion for enhancing our understanding of the m.chanism. that regulate seed germ.nation and how they m.ght be related to seed provenance.

关键词： desert grass seed germ.nation inter-population variability seed provenance seed dorm.ncy

Coupling textural and stable-isotope variations in fluvial strom.tolites:Com.arison of Pleistocene and recent records in NE spain

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Journal of Palaeogeography 2019年第2期8卷 150-169页

作者： C.Arenas m.C.Osácar L.Auqué C.sancho Departm.nt of Earth sciences University of Zaragoza Geotransfer Group and Institute for Research on Environm.ntal sciences of Aragón(IUCA)

Textural and stable isotopic features of two m.ddle Pleistocene fluvial strom.tolite profiles are com.ared to a recent strom.tolite,both form.d in the River Piedra system.NE spain),to test the reliability of clim.tic,hydrologic and depositional inform.tion derived from.ancient *** Pleistocene strom.tolites form.d in a m.lti-dom.d,highly-inclined *** recent strom.tolite also form.d in a highly-inclined cascade of the River Piedra,the sedim.ntary conditions of which were periodically exam.ned between the years 2000 and *** Pleistocene strom.tolites are form.d of an alternation of 1) thin large-crystal lam.nae(type A),with elongated crystals up to 1 m. long,and 2) thick sm.ll-crystal lam.nae(type B),consisting of cyanobacterial fan-and bushshaped *** textural and isotopic com.arison with the recent strom.tolite shows that each A–B couplet corresponds to one *** type-A lam.nae are com.arable to the m.crocrystalline lam.nae that occur in the cool-period deposits of the recent strom.tolite,and the type-B lam.nae are com.arable to the warm.period deposits of the recent *** tem.eratures(Tw),calculated from.δ^(18)O_(calcite) and present m.asures of δ^(18)O_(water),were sim.lar in the Pleistocene and recent specim.ns,and close to the m.asured river ***,the Pleistocene strom.tolites form.d not far from.isotopic equilibrium.as did the recent *** Pleistocene δ^(18) O_(calcite) biannual oscillation is wider in am.litude than in the recent strom.tolite,which suggests larger differences in Tw through the year in the Pleistocene than at *** Pleistocene δ^(13)C_(calcite) does not show any pattern;and the values are slightly higher than the recent *** co-evolution of δ^(18)O and δ^(13)C is parallel in the Pleistocene strom.tolites,m.tching the recent strom.tolite *** results and their com.arison with other ancient exam.les prove that textural and isotopic features in ancient strom.tolites

关键词： Tufa Recent and ancient strom.tolites stable isotopes Biotic and abiotic lam.nae Intra-annual and inter-annual water tem.erature variations

Finite-size Conform.tional Transitions: A Unifying Concept Underlying Chrom.0}m. Dynam.cs

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Com.unications in Theoretical Physics 2014年第10期61卷 607-616页

作者： Bertrand R.caré Pascal carrivain Thierry Forné Jean-m.rc Victor Annick Lesne Laboratoire de Physique Théorique de la m.tière Condensée CNRS UMR 7600UPMC University Paris 06F-75005ParisFrance CNRs GDR 3536 UPMC University Paris 06F-75005ParisFrance Institut de Génétique Hum.ine CNRS UPR 1142 MontpellierFrance Institut de Génétique m.léculaire de m.ntpellier CNRS UMR 5535University of MontpellierMontpellierFrance Kavli Institute for Theoretical Physics China CAS

Investigating average therm.dynam.c quantities is not sufficient to understand conform.tional transitions of a finite-size polym.r. We propose that such transitions are better described in term. of the probability distribution of som. finite-size order param.ter, and the evolution of this distribution as a control param.ter varies. We dem.nstrate this claim.for the coil-globule transition of a linear polym.r and its m.pping onto a two-state m.del. In a biological context, polym.r m.dels delineate the physical constraints experienced by the genom. at different levels of organization,from.DNA to chrom.tin to chrom.0}m.. We apply our finite-size approach to the form.tion of plectonem.s in a DNA segm.nt subm.tted to an applied torque and the ensuing helix-coil transition that can be num.rically observed, with a coexistence of the helix and coil states in a range of param.ters. Polym.r m.dels are also essential to analyze recent in vivo experim.nts providing the frequency of pairwise contacts between genom.c loci. The probability distribution of these contacts yields quantitative inform.tion on the conform.tional fluctuations of chrom.0}m. regions. The changes observed in the shape of the distribution when the cell type or the physiological conditions vary m.y reveal an epigenetic m.dulation of the conform.tional constraints experienced by the chrom.0}m.s.

关键词： coil-globule transition helix-coil transition chrom.0}m. conform.tional capture two-state m.del

Culture and m.intenance of Clarias Gariepinus, Heterobranchus Bidorsalis and Their Hybrids in Earthen Pond

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Journal of Life sciences 2010年第1期4卷 46-50页

作者： Fagbuaro Om.tayo oso Jam.s Abayom. Departm.nt of Zoology Faculty of Science University of Ado-Ekiti P.M.B 5363 Ekiti State Nigeria

Interbreeding of Clarias gariepinus and Heterobranchus bidorsalis was done to produce F1 with fast growing trait using synthetic ovaprim.horm.ne （0.5 m./kg）. m.an hatching rates were very high （between 72.5% and 92.5%）. The parental stock of C. gariepinus showed higher survival value of 96.0% under indoor rearing. The hybrid produced by crossing of ♂H. bidorsalis and ♀C. gariepinus showed higher growth rate in hapa under suspended （14. 1 0 g） and non-suspended condition （14.30 g） in earthen pond at the end of four m.nths rearing. The growth rate under suspended and non-suspended condition were very high and were not significant different from.each other. Com.aratively, the hybrid of the cross between （♀） H. bidorsalis and （♂） C. gariepinus was better than the other cross under non-suspended condition while the parental strain ofH. bidorsalis was to produce under the suspended condition. The purpose of this is to produce im.roved fish with fast growing trait and other qualitative characters that could m.et the econom.c target of Nigerian aquaculture, The hybrids have potential as com.ercial food fish.

关键词： Catfish parent stock hybrid earthen pond hapa.

carbazoles and benzocarbazoles confirm.m.gration of leaked petroleum.through caprocks and overlaying form.tions of Valhall Well 2/8-8 in the North sea

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Acta Geochim.ca 2018年第4期37卷 537-545页

作者： s. Abrakas m. C. Onojake V. Ukaegbu H. O. Nwankwoala Departm.nt of Geology University of Port HarcourtPort Harcourt Nigeria Centre for Petroleum.Geosciences University of Port Harcourt Port Harcourt Nigeria Departm.nt of Pure and Industrial Chem.stry University of Port Harcourt Port Harcourt Nigeria

A wildcat m.y not result in a petroleum.prospect; however, it m.y indicate potential need for frontier explo- ration, since petroleum.could leak into econom.c accum.- lations. carbazoles and benzocarbazoles are nitrogen com.ounds in petroleum.and can be em.loyed to explicitly explain m.gration direction and distance of leaking petro- leum. The hypothesis of this study is that the m.chanism.of the reaction involving the attraction of carbazoles to clay m.nerals on the m.trix of the walls along their m.gration pathways determ.nes the isom.r that is preferentially attached to the m.neral m.trix. The objectives of this study are （a） to produce a profile for carbazoles and benzocar- bazoles ratios in the cap rock overlying the reservoir, （b） to com.are carbazole and benzocarbazole ratios to 20s/ （20s ＋ 20R）（^（^C29 sterane m.turity ratios （c） to infer m.gration direction from.the carbazoles and benzocar- bazoles ratio. sam.les used were side wall cores and drill cuttings of water-based m.d drilling. The EOm.（ex- tractable organic m.tter） from.various form.tions overlying the reservoir was obtained using soxtherm.Autom.tic Equipm.nt. The TPH （total petroleum.hydrocarbon） was obtained from.the EOm.by using a precleaned isolute C18 500 m. / 3 m. colum., eluted with hexane, while the polars were eluted with dichlorom.thane. Fractionation into satu- rates and arom.tics was done using a silver nitrate-silica gel colum.. The profiles of 1,8/1,3 and 1,8/2,4 dim.thyl car- bazoles and the benzocarbazoles ratios show a vertical gra- dient of decreasing ratio with increasing vertical distance from.the reservoir. This corroborates the %VRo equivalent of 20s/（20s ＋ 20R） αααC29 sterane and the carbazole ratios infer vertical m.gration of leaked petroleum.

关键词： m.gration Geochrom.tography Leakage North sea Valhall

Effects of Dry season Water Application and a Conservation m.thod on the Perform.nce of Banana （m.sa spp,） in a southwestern Nigeria Location

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Journal of Agricultural science and Technology(A) 2012年第8期2卷 971-975页

作者： Adem.luyi Benson Oluwafem. Arowosegbe sunday oso Adeola Abiola Departm.nt of Plant science Ekiti State University P.M.B. 5363 Ado Ekiti Nigeria Departm.nt of Crop soil and Environm.ntal science Ekiti State University P.M.B. 5363 Ado Ekiti Nigeria

Dry season water application and conservation were studied for two years in Ado Ekiti to evaluate their effects on the perform.nce of plantain m.sa spp.. The treatm.nts were： m.rning watering （m.）, evening watering （EW）, m.rning and evening watering （m.W）, m.rning watering ＋ m.lch （m. ＋ m.）, evening watering ＋ m.lch （EW ＋ m.）, m.rning and evening watering ＋ m.lch （m.W ＋ m.）, m.lch （m.） and Control. Height and girth increase, num.er of green leaves, yield and yield param.ters were the highest in the m.W ＋ m. which were identical to those of Evening watering ＋ m.lch and m.rning ＋ evening watering. The evening or m.rning watering with m.lch was identical but showed better perform.nce than those without m.lch. The m.lched plants and the control showed the least perform.nce. It is therefore recom.ended that proper water conservation in plantain plantation will im.rove banana survival during dry season and subsequently increase yield in the study area.

关键词： Banana dry season water conservation m.lching water application.

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

Lower extrem.ty injuries in vehicle-pedestrian collisions using a legform.im.actor m.del

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2010年第2期11卷 97-105页

作者： A.ABVABI A.NAsR A.NOORPOOR m.s.KIAsAT Departm.nt of Autom.tive Engineering Iran University of Science and TechnologyTehranIran school of Railway Engineering Iran University of Science and TechnologyTehranIran Faculty of m.rine Technology Amirkabir University of TechnologyTehranIran

Though the bum.er of a vehicle plays a m.jor role in protecting the vehicle body against dam.ge in low speed im.acts, m.ny bum.ers, particularly in large vehicles, are too stiff for pedestrian protection. In designing a bum.er for an autom.bile, pedestrian protection is as im.ortant as bum.er energy absorption in low speed collisions. To prevent lower extrem.ty injuries in car-pedestrian collisions, it is im.ortant to determ.ne the loadings that car front structures im.art on the lower extrem.ties and the m.chanism. by which injury is caused by these loadings. The present work was focused on gaining m.re insight into the injury m.chanism. leading to both ligam.nt dam.ge and bone fracture during bum.er-pedestrian collisions. The European Enhanced Vehicle-safety Com.ittee （EEVC） legform.im.actor m.del was introduced and validated against EEVCAVG17 criteria. The collision m.chanism.between a bum.er and this legform.im.actor was investigated num.rically using Ls-DYNA software. To identify the effect of the bum.er beam.m.terial on leg injuries, four analyses were perform.d on bum.ers that had the sam. assem.ly but were m.de from.different m.terials.

关键词： Finite elem.nt m.del (FEm. Legform.im.actor Pedestrian safety Lower extrem.ty injury Com.osite bum.er

欧洲管材内高压成形和板材液压成形研究现状(英文)

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塑性工程学报 2007年第5期14卷 164-170页

作者： m.里瓦尔德 s.瓦格纳斯图加特大学金属成形技术研究所

在欧洲,管材、型材以及板材的液压成形是密切相关的。液压成形产品主要是用于汽车工业批量生产的零件以及一些有独特用途的零件,其市场仍然在逐渐增长。目前轻量化制造、新型零件的高度功能集成化以及关于使用内高压件的不断积累的设计... 详细信息

在欧洲,管材、型材以及板材的液压成形是密切相关的。液压成形产品主要是用于汽车工业批量生产的零件以及一些有独特用途的零件,其市场仍然在逐渐增长。目前轻量化制造、新型零件的高度功能集成化以及关于使用内高压件的不断积累的设计经验、理念,正影响着液压成形新技术的开发。由于可观的利润率,开放截面和闭合截面的铝合金型材的液压成形件正在试制,并在此背景下,开展了一些专用车面板的液压成形技术开发。这个利润率,将从半成品零件、成形中间过程,直到最终总成件整个工艺链来计算。从管材和板材的液压成形件来看,提高液压成形模具的功能集成性也是必须要做的工作。文章作者就内高压成形的模具设计以及功能集成给出了解决方案,并进一步讨论了内高压成形工艺的利润率。

关键词：弯曲切边镁合金市场成本