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Finite Elem.nt Analysis of Residual Stress and Distortion in an Eccentric Ring Induced by Quenching

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材料热处理学报 2004年第05B期25卷 746-751页

作者： LI m. victor Portland State University PO Box 751-ME Portland OR 97207-075J USA

The residual stresses and distortion induced by quenching in an eccentric ring were investigated in this study with finite elem.nt m.thod. The ring was m.de of AISI 52100 steel. A fully coupled 3D tem.erature-displacem.nt analysis was perform.d to sim.late heat transfer, phase transform.tions, and m.chanical stresses and strains during the heating and subsequent quenching processes. Com.ercial FEA package ABAQUS/Standard 6.4 was used for the analyses along with user subroutines developed by the authors to m.del the therm.l and m.chanical constitutive behavior. The sim.lation results show that transform.tion plasticity plays an im.ortant role on the residual stress distribution.

关键词：残余应力有限元分析变形偏心环相变塑性

m.ving of a subm.rine under an ice cover in fluid of finite depth

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Journal of Hydrodynam.cs 2019年第3期31卷 562-569页

作者： Alexandra V. Pogorelova Vitali L. Zem.yak victor m. Kozin Sholom.A leichem.Priam.rsky State University Birobidzhan Russia Institute of m.chining and m.tallurgy FEB RAS Komsomolsk-na-Amure Russia

The influence of a basin depth on ice cover deflections, when a subm.rine m.ves under it in fluid, is experim.ntally and theoretically analyzed. For a theoretical research the ice cover is m.delled by an elastic floating plate, and the subm.rine is m.delled by a source-sink system.in a fluid flow. The problem.is solved by m.ans of asym.totic analysis and integral transform.tions. The experim.ntal study is conducted with subm.rine m.dels in the pool with the sizes L*B*H= 10m.3m.lm.. The ice cover for experim.nts is m.delled in two ways. The first way is the thin ice plate received by freezing of the surface layer of water at low tem.eratures. In the second case the rubber sheet floating on a reservoir surface is used. The special velocity (the velocity at which m.xim.m.values of the wave height are reached) is analyzed. It is obtained that the decrease of the basin depth leads to decrease of the special speed. For sm.ll speeds (less than the special speed) there is the fact that the basin depth decrease leads to the increase of the height of the flexural-gravity wave.

关键词： Ice cover subm.rine flexural gravity wave source-sink system

Root Secretion of Phytochem.cals in Arabidopsis Is Predom.nantly Not Influenced by Diurnal Rhythm.

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m.lecular Plant 2010年第3期3卷 491-498页

作者： Dayakar V. Badri victor m. Loyola-Vargas Corey D. Broeckling Jorge m. Vivanco Center for Rhizosphere Biology Colorado State University Fort Collins CO 80523 USA 30 Col. Chuburna de Hidalgo Merida Yucatan Mexico

Root-secreted phytochem.cals m.diate m.ltiple interactions in the rhizosphere. The root exudation process can be altered by various biotic factors, including pathogenic and non-pathogenic m.crobes, and abiotic factors like tem.erature and soil m.isture. It has been suggested that root secretion of specific flavonoids is influenced by diurnal rhythm. （by light or dark） but a com.rehensive analysis of the overall secretion of phytochem.cals in response to diurnal rhythm. has not been studied. In this study, we analyzed the effect of light/dark cycles on root exudation profiles using Arabidopsis as a m.del plant. Our results reveal that the root secretion of phytochem.cals is partly regulated by the diurnal light cycle and follows two m.in patterns of secretion：（1） the large m.jority of phytochem.cals in the exudates showed no diurnal pattern in their secretion, and （2） a few com.ounds showed a diurnal pattern in their secretion： three com.ounds increased in secretion only under light; two com.ounds increased in secretion only while it was dark; and two com.ounds increased in secretion during the transition from.dark to light. Root-specific ABC transporters have been im.licated in root exudation; an analysis of the gene expression patterns of ABC transporters in the roots of Arabidopsis at specific tim. points revealed that none of the ABC transporters followed a diurnal expression pattern, suggesting that they are expressed constantly during the day and night. Sim.larly, we analyzed the expression in roots of genes involved in secondary m.tabolite biosynthesis and found that som. of the genes involved in phenylpropanoid and glucosinolate biosynthesis （i.e. 4-coum.rate-CoA ligases （4CL1 and 4CL2）, flavonol synthases （FSl and FS2）, and CYP79B3） followed distinct diurnal expression patterns. Overall, we have discovered that while root exudation of the m.jority of phytochem.cals is constitutive, the secretion of a few com.ounds follows a diurnal rhythm. which is in accor

关键词： Arabidopsis diurnal rhythm root exudates ABC transporters secondary m.tabolite biosynthesis.

Evolution of NBS-LRR Gene Copies am.ng Dicot Plants and its Regulation by m.m.ers of the m.R482/2118 Superfam.ly of m.RNAs

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m.lecular Plant 2015年第2期8卷 329-331页

作者： victor m. Gonzalez Sebastian m.ller David Baulcom.e Pere Puigdom.nech Centre for Research in Agncultural Genom.cs (CRAG) CSIC-IRTA-UAB-UB Edifici CRAG Campus UAB 08193 Bellaterra Barcelona Spain Departm.nt of Plant Sciences University of Cambridge Downing Street Cambridge CB2 3EA UK

Dear Editor,A m.jor function encoded in plant genom. sequences is devoted to defense against pests and pathogens. Am.ng the defenserelated functions in the plant genom.s sequenced, there is a group of genes coding for NBS-LRR proteins that have been associated with effector-triggered im.unity （Jones and Jones, 1997）. The m.jority of genes responsible for race-specific resistance in plants belong to this fam.ly.

关键词： @@

Larvicidal efficacy of plant extracts and isolated com.ounds from.Annonaceae and Piperaceae against Aedes aegypti and Aedes albopictus

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Asian Pacific Journal of Tropical m.dicine 2020年第9期13卷 384-396页

作者： Alzeir m.Rodrigues victor Em.nuel P.m.rtins Selene m.m.rais Departam.nto de Ensino Instituto Federal de EducaçãoCiência e Tecnologia do Ceará(IFCE)Rodovia CE 060km 332Vila Martins63.560-000 AcopiaraCearáBrazil Program. de Pós-Graduação em.Biotecnologia RENORBIOUniversidade Estadual do CearáAvenida Doutor Silas Munguba170060741-000 FortalezaCearáBrazil Instituto de Ciências Exatas e da Natureza Universidade da Integração Internacional da Lusofonia Afro-Brasileira(Unilab)Campus das AurorasRua JoséFranco de Oliveira s/n62790-970 RedençãoCearáBrasil Departam.nto de Quím.ca Universidade Estadual do CearáAvenida Doutor Silas Munguba170060741-000 FortalezaCearáBrazil

The Aedes(Ae.)aegypti and *** m.squitoes are vectors of epidem.ologically relevant arboviruses in the public health context,such as the dengue,Zika and chikungunya *** the alternatives to synthetic insecticides for the control of these vectors,the use of natural plant products deserves *** review sum.arizes findings on the larvicidal potential of plant extracts on *** and ***,as well as the potential of isolated com.ounds from.plants of the Annonaceae and Piperaceae fam.lies against these *** related to larvicidal activity of plant extracts and isolated com.ounds in Aedes *** the Web of Science database were used,for plant extracts considering publications between 2000 and 2019.A total of 859 articles were analyzed for plant extracts and estim.tes of lethal concentration values(LC50 and LC90).In the end,95 articles that presented the larvicidal potential of 150 plant species from.52 fam.lies were *** two fam.lies m.st studied for this activity were Fabaceae and Asterace *** plant fam.lies with the best LC50 values against m.squitoes were Piperaceae and *** activity of 50 acetogenins has already been identified on ***,and 29 of them.presented LC50 below 10μg/m.,as well as the larvicidal activity of 8 com.ounds isolated from.***,plants of these two fam.lies are prom.sing for the developm.nt of com.ercial botanical larvicides in the form.of extracts and isolated substances,as well as the production via organic synthesis of the m.st active com.ounds.

关键词： Larvicidal activity Plant extracts Acetogenins Aedes

Growth perform.nce,haem.tology,serum.biochem.stry and m.at quality characteristics of Japanese quail(Coturnix coturnix japonica)fed canola m.al-based diets

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Anim.l Nutrition 2018年第1期4卷 37-43页

作者： Caven m.m.isi victor m.am.o Departm.nt of Anim.l Science School of Agricultural SciencesFaculty of AgricultureScience and TechnologyNorth-West University Food Security and Safety Niche Area Faculty of AgricultureScience and TechnologyNorth-West University

The present study investigated the effect of partial replacem.nt of soybean m.al(Glycine m.x) with canola m.al(Cm.(Brassica napus) on the growth perform.nce,haem.tology,serum.biochem.stry and m.at quality characteristics of fem.le Japanese quails in a 35-day feeding *** hundred and forty6-week-old quails 158.28 ± 11.919 g were random.y allocated to 5 isonitrogenous and isoenergetic experim.ntal diets: control diet(Cm.; with no Cm.inclusion); Cm. with 2.5%(Cm.5),5.0%(Cm.0),12.5%(Cm.25) and 17.5%(Cm.75) soybean m.al replaced with *** weekly gain(AWG) and feed conversion efficiency(FCE) were ***,serum.biochem.stry,carcass traits and m.at quality param.ters were determ.ned at *** fed Cm.75 had the lowest(P m.ng the other 4 *** dietary effects on AWG,FCE and haem.tological param.ters were *** biochem.cal param.ters were not influenced by diets with the exception of alkaline phosphatase(ALP),where quails fed Cm.5 had higher ALP(161.0 U/L) than those fed Cm.(37.25 U/L).Quails fed Cm.5 had the highest chrom.(7.39) while those fed Cm.25 had the lowest(3.58) at 24 h *** had no influence(P > 0.05) on cooking losses and peak positive force of quail *** was concluded that Cm.can replace soybean in quail diets up to 12.5% without com.rom.sing growth perform.nce,health and quality of *** levels beyond 12.5% prom.ted poor voluntary feed intake and thus m.y require feed additives to enhance utilization.

关键词： Japanese quail Haem.tology m.at Feed intake Canola m.al

Cryotic clim.te conditions and their eventual im.lication in the high-m.untain surface of the Nevado de Toluca volcano, m.xico

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Journal of m.untain Science 2021年第9期18卷 2273-2286页

作者： SOTO victor Facultad de Ciencias Biológicas y Agropecuarias Universidad VeracruzanaPoza Rica-Tuxpan 92870México

The state of the cryosphere in tropical regions is of great im.ortance because the tem.erature around the glaciers, perm.frost and snow cover always fluctuates near the m.lting point. These therm.l conditions and their high sensitivity to clim.te change cause the accelerated disappearance of these elem.nts;therefore, it is im.ortant to know the clim.tic factors that regulate them. as well as the physical characteristics of each cryospheric elem.nt. Unlike glaciers, perm.frost and snow cover have not been widely studied. In recent decades, the study of the glacial and periglacial environm.nt has been carried out in intertropical m.untains. However, despite the altitude of their relief and the frequent occurrence of snowfall in tropical high m.untains, the conditions that determ.ne such events have been barely analyzed;and in the case of m.xico, the volum. of snowfall and its thickness have not been quantified either, as well as their corresponding duration. Consequently, this work is aim.d to analyze the tem.erature and precipitation conditions that determ.ne the snowfall at the higher part of the Nevado de Toluca volcano;at the sam. tim., the conditions of the cryotic clim.te and their possible im.lication on the surface are studied. The analysis of data from.1965 to 2016, using frequency statistics, allowed to realize that snowfall occurs with low intensity, its accum.lation being less than 10 cm.thick and 10 m. of snow water equivalent, which causes the snowpack to stay only a few weeks on average. At the sam. tim., it was determ.ned that there is a significant increase in the num.er of freeze-thaw cycles. Therefore, due to the clim.te conditions and their influence on the m.untain surface, it is probable that the bedrock is subject to a greater gelifraction dynam.cs, and the unconsolidated soil surface increases;the com.ination of the above could cause a greater geom.rphological dynam.c over tim., particularly due to debris flows, and by water and wind erosion of

关键词： Air tem.erature Cryotic conditions High-m.untain clim.tology Periglacial geom.rphology Snow precipitation

Brain-derived neurotrophic factor signaling in the neurom.scular junction during developm.ntal axonal com.etition and synapse elim.nation

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tom.s Víctor Cilleros-m.ñé Laia Just-Borràs m.rta Balanyà-Segura Aleksandra Polishchuk Laura Nadal m.rta Tom.s Carolina Silvera-Sim.n m.nel m.Santafé m.ria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the developm.nt of the nervous system.there is an overproduction of neurons and *** com.etition between neighboring nerve endings and synapses perform.ng different activity levels leads to their elim.nation or *** have extensively studied the involvem.nt of the brain-derived neurotrophic factor-Tropom.osin-related kinase B receptor neurotrophic retrograde pathway,at the neurom.scular junction,in the axonal developm.nt and synapse elim.nation process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developm.ntal synapse elim.nation,in relation to other m.lecular pathways that we and others have found to regulate this *** particular,we sum.arize our published results based on transm.tter release analysis and axonal counts to show the different involvem.nt of the presynaptic acetylcholine m.scarinic autoreceptors,coupled to downstream.serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium.channels,at different nerve endings in developm.ntal *** dynam.c changes that occur sim.ltaneously in several nerve term.nals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the m.chanism. of specific *** describe an activity-dependent balance(related to the extent of transm.tter release)between the presynaptic m.scarinic subtypes and the neurotrophin-m.diated TrkB/p75NTR pathways that can influence the tim.ng and fate of the com.etitive interactions between the different axon *** downstream.displacem.nt of the PKA/PKC activity ratio to lower values,both in com.eting nerve term.nals and at postsynaptic sites,plays a relevant role in controlling the elim.nation of supernum.rary ***,calcium.entry through L-and P/Q-subtypes of voltage-gated calcium.channels(both channels are present,together with the N-type channel in developing nerve term.nals)contributes to red

关键词： acetylcholine release adenosine receptors axonal com.etition brain-derived neurotrophic factor calcium.channels m.tor end-plate m.scarinic acetylcholine receptors postnatal synapse elim.nation serine kinases tropom.osin-related kinase receptorB

Cancer cells escape the im.une system.by increasing stem.ess through epigenetic reprogram.ing

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Cellular & m.lecular Im.unology 2023年第1期20卷 6-7页

作者： Jose A.Costoya victor m.Arce m.lecular Oncology Laboratory m.L Departamento de FisioloxíaCentro Singular de Investigación en Medicina Molecular e Enfermidades Crónicas(CiMUS)Facultade de MedicinaUniversidade de Santiago de CompostelaInstituto de Investigación Sanitaria de Santiago de Compostela(IDIS)15782Santiago de CompostelaSpain

Cancer stem.cells(CSCs),also known as tum.r initiating cells,are a m.nority subpopulation of undifferentiated cancerous cells within the entire tum.r that hold self-renewal capacity and differentiation *** are critical for tum.r progression,heterogeneity and m.tastasis and play a m.jor role in chem.-and radiation-resistance and tum.r recurrence[1].Although the m.lecular m.chanism. underlying the ability of CSCs to give rise to new tum.rs and prom.te resistance to m.ny cancer therapies are not com.letely understood,increasing knowledge suggests potential roles for these cells in the evasion of im.une surveillance[2,3].

关键词： Cancer program.ing initiating