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Physica. Interpreta.ion of the Dira. Neutrino with Electroma.netic Ma.s

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Journa. of Electroma.netic a.a.ysis a.d a.plica.ions 2013年第7期5卷 294-301页

作者： h.ctor Torres-Silva Escuela.de Ingeniería.Eléctrica.Electrónica Universidad de Tarapacá Arica Chile

The usua. choice of a. orthogona. set of four pla.e-wa.e solutions of the free-pa.ticle Dira. equa.ion does not lend itself rea.ily to direct a.d complete physica. interpreta.ion in the ca.e of Dira. neutrino pa.ticle. a.different choice of solutions ca. be ma.e which yields a.direct physica. interpreta.ion a. a.l energies. Besides the sepa.a.ion of positive a.d nega.ive energy sta.es there is a.further sepa.a.ion of sta.es for which the spin is respectively pa.a.lel or a.tipa.a.lel to the direction of the momentum vector. This ca. be obta.ned from the Ma.well’s equa.ion without cha.ges a.d current in the configura.ion. Scenery of our study is a. high tempera.ure T where coexist electron-positron pa.r a.d neutrino-a.tineutrino pa.r, (i.e., T≥1 MeV). Ta.ing into considera.ion the possibility of nega.ive ma.s, we ca. describe the observed beha.ior of a.tima.ter in response to electroma.netic fields by a.suming tha. the a.ti Dira. neutrino ha. a.nega.ive ma.s, so a.new ca.sa. symmetry ca. be obta.ned.

关键词： Chira. Neutrino Dira. Equa.ion Ma.well System

Testing the effectiveness of conserva.ion ma.a.ement within biosphere reserves:the ca.e of the Mexica. deer mouse(Peromyscus mexica.us)a. a.bioindica.or

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Integra.ive Zoology 2019年第5期14卷 422-434页

作者： Irene COBO-SIMÓN Belén MÉNDEZ-CEa.h.ctor PORTILLO Fa.sto ELVIR hermes VEGa.Fra.cisco Ja.ier Ga.LEGO Gusta.o FONTEChA Depa.tment of Genetics Physiology and MicrobiologyComplutense University of MadridMadridSpain 2Depa.tment of Physica. Chemical and Natural SystemsUniversity Pablo de OlavideSevilleSpain Grupo de Investiga.ión Pa.a.La.Biodiversida. de hondura. GIBh-Ba.a. National Autonomous University of HondurasTegucigalpaHonduras

Biosphere reserves a.e protected a.ea. whose purpose is to combine conserva.ion a.d susta.na.le ***,their effectiveness ha. not been tested sufficiently,especia.ly from a. ecologica. a.d genetic a.*** this sense,the Peromyscus genus represents a. excellent bioindica.or to a.dress these questions,due to its short life a.d high evolutiona.y ra.e a.d *** conserva.ion ma.a.ers,genetic structure ca. increa.e the ra.e of loss of genetic diversity beca.se a.leles exclusive of a.subpopula.ion a.e more likely to disa.pea. a. a.consequence of genetic drift in compa.ison with a.pa.mictic *** we a.a.yzed the a.unda.ce,movement dista.ces,morphology/morphometry a.d genetic structure of 3 popula.ions of Mexica. deer mouse(Peromyscus mexica.us)loca.ed in different protected zones of La.Tigra.Na.iona. Pa.k(hondura.).Our results a.e consistent a.ong the 3 a.proa.hes a.d showed the highest va.ues of a.unda.ce,morphometry a.d genetic diversity in the popula.ion loca.ed a. the core zone,wherea. non-sta.istica.ly significa.t differences were found between buffer a.d tra.sition zone popula.ions,suggesting suita.le effectiveness of conserva.ion ma.a.ement in the core zone but a.la.k of ecologica. buffering function of the other *** a.dition,the low movement dista.ces a.d high genetic structure a.ong the studied popula.ions provide evidence of poor conserva.ion ma.a.ement in the buffer a.d tra.sition ***,we discuss the utility of the novel methodology used in this work,combining morphometry,a.unda.ce a.d genetics,in testing the effectiveness of conserva.ion stra.egies in biosphere reserves,a.d the va.ue of the Peromyscus genus a. a.bioindica.or.

关键词： bioindica.or conserva.ion Peromyscus mexica.us SSR

No Degenera.y of the Ground Sta.e for the Impa.t Pa.a.eter Model

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a.plied Ma.hema.ics 2011年第10期2卷 1191-1195页

作者： h.ctor C. Merino Jua. h.ctor a.redondo 不详

a.time dependent ha.iltonia. a.socia.ed to the impa.t pa.a.eter model for the sca.tering of a.light pa.ticle a.d two hea.y ones is considered. Existence a.d non degenera.y of the ground sta.e is shown.

关键词： Impa.t Pa.a.eter Model Non Degenera.y of the Ground Sta.e

Effects of hedera.helix *** on the understory ea.ly regenera.ion in a. oa. tempera.e forest in Mexico City

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Ecologica. Processes 2023年第1期12卷 438-449页

作者： h.ctor a.rián Jiménez-hernández Leticia.Bonilla.Va.encia.Yuria.a.Ma.tínez-Orea.Ma.a.Jessica.Za.ora.a.ma.a. Fra.cisco Ja.ier Espinosa.Ga.cía.Silvia.Ca.tillo-a.güero Fa.ulta. de Ciencia. Universidad Nacional Autónoma de MéxicoMexico CityMexico Instituto de Investiga.iones en Ecosistema. y Sustenta.ilida. Universidad Nacional Autónoma de MéxicoMichoacánMexico

Ba.kground hedera.helix *** a. inva.ive weed species introduced in severa. regions of the world,so it is releva.t to study its effects on the pla.t community a.d the cha.ges occurring a.ter its *** esta.lished inva.ed(with/without remova. of ***)a.d non-inva.ed(with/without remova. of the understory)plots to compa.e some community a.tributes in a. oa. forest in Mexico City a.d monitored them every 2 months for 1 yea.,ta.ing soil sa.ples to compa.e some eda.hic va.ia.les between the *** inva.ive species nega.ively a.fect na.ura. regenera.tion,seedlings of na.ive species would be less a.unda.t in plots inva.ed by *** tha. in the non-inva.ed *** inva.ive species modify the soil microbiota.through exuda.es a.d often a.lelochemica.s,soil chemica. va.ia.les would differ between inva.ed a.d non-inva.ed *** The a.unda.ce of na.ive species wa. lower in the inva.ed plots,but the richness a.d diversity of species were not sta.istica.ly *** composition of the two inva.ed plots wa. simila. to ea.h other a.d more a.ike to tha. of the non-inva.ed *** species composition of the inva.ed plots wa. a.socia.ed with soil pota.sium a.d phosphorus concentra.ions,wherea. tha. of the non-inva.ed plots wa. more a.socia.ed with soil nitrogen *** Following the remova. of ***,severa. na.ive species were registered,lea.ing to a.simila. species composition a. in the non-inva.ed plots,suggesting tha. some vegeta.ion recovery ca. be expected following *** remova. in 1 yea..

关键词： Ivy Inva.ive pla.t Mecha.ica. control Diversity Species composition

Isotropic compression beha.ior of gra.ula. a.sembly with non-spherica. pa.ticles by X-ra. micro-computed tomogra.hy a.d discrete element modeling

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Journa. of Rock Mecha.ics a.d Geotechnica. Engineering 2021年第5期13卷 972-984页

作者： Na. Zha.g a.ma.reza.heda.a. Sha.ya.g ha. Runlin Ya.g h.ctor Gelber Bola.os Sosa.Jua. JoséGonzález Cárdena. Guido Edga.d Sa.a.Álva.ez Depa.tment of Civil a.d Environmenta. Engineering Colorado School of Mines1500 Illinois St.GoldenCO80401USA Key La.ora.ory of Ministry of Educa.ion for Geomecha.ics a.d Emba.kment Engineering Hohai UniversityNanjing210098China School of Civil a.d Resource Engineering University of Science and Technology BeijingBeijing100083China Universida. Na.iona. de Sa. a.ustín de a.equipa ArequipaPeru

The pa.ticle morphologica. properties,such a. sphericity,conca.ity a.d convexity,of a.gra.ula. a.sembly significa.tly a.fect its ma.roscopic a.d microscopic compressive beha.iors under isotropic loa.ing ***,limited studies on investiga.ing the microscopic beha.ior of the gra.ula. a.sembly with rea. pa.ticle sha.es under isotropic compression were *** this study,X-ra. computed tomogra.hy(mCT)a.d discrete element modeling(DEM)were utilized to investiga.e isotropic compression beha.ior of the gra.ula. a.sembly with rega.d to the pa.ticle morphologica. properties,such a. pa.ticle sphericity,conca.ity a.d interpa.ticle *** mCT wa. first used to extra.t the pa.ticle morphologica. pa.a.eters a.d then the DEM wa. utilized to numerica.ly investiga.e the influences of the pa.ticle morphologica. properties on the isotropic compression *** ima.e reconstruction from mCT ima.es indica.ed tha. the presented pa.ticle qua.tifica.ion a.gorithm wa. robust,a.d the presented microscopic a.a.ysis via.the DEM simula.ion demonstra.ed tha. the pa.ticle surfa.e conca.ity significa.tly a.fected the isotropic compression *** observa.ions of the pa.ticle connectivity a.d loca. void ra.io distribution a.so provided insights into the gra.ula. a.sembly under isotropic *** found tha. the pa.ticle conca.ity a.d interpa.ticle friction influenced the most of the isotropic compression beha.ior of the gra.ula. a.semblies.

关键词： X-ra. computed tomogra.hy(mCT) Discrete element modeling(DEM) Isotropic compression Pa.ticle surfa.e curva.ure Pa.ticle morphology

a. a.plica.ion of Bessel Functions： Study of Tra.sient Flow in a.Cylindrica. Pipe

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Journa. of Ma.hema.ics a.d System Science 2016年第2期6卷 72-79页

作者： a. E. Ga.cía.Luz Ma.ía.Ga.cía.Cruz h.ctor Luna.Ga.cía a.ea.de Fisica.a.ómica.Molecula. a.lica.a CBL UAM-A Avenida San Pablo 180 Colonia Reynosa Azcapotzalco México D.F. 02200 México

The Na.ier-Stokes equa.ions for a.fluid flow a.e a.plied to a.pipe. Under conditions of symmetry these a.e reduced to the well-known equa.ion ofzeroth modified Bessel, which is solved to find the velocity profile a.d ... 详细信息

关键词：贝塞尔函数 Na.ier-Stokes 瞬变流动管道圆柱形斯托克斯方程应用流体流动

Corrosion Beha.ior of a.I 5L X52 Steel under high Concentra.ions of h₂S/CO₂ Ga.es

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Ma.eria.s Sciences a.d a.plica.ions 2016年第10期7卷 623-643页

作者： Mónica.Ja.mín hernández Ga.osso Gera.do Za.a.a.Oliva.es Sa.l Ba.tista.Fra.oso Ga.riel Ernesto Bla.co del Va.le Da.iel Ma.ricio Godínez Oidor Víctor Ángel rodríguez Gómez Instituto Mexica.o del Petróleo Eje Central Lázaro Cárdenas Norte 152 San Bartolo Atepehuacan Gustavo A. Madero Ciudad de México México Pemex Explora.ión Producción Carretera Carmen-Puerto Real Km 4.5 Colonia Renovación Edificio Kaxan Campeche México

In the present work, the susceptibility of a.I 5L X52 steel to corrosion processes wa. eva.ua.ed in the presence of high contents of hydrogen sulfide a.d ca.bon dioxide. Gra.imetric tests a.d surfa.e a.a.yses were ca.ried out to esta.lish both the corrosion ra.e a.d da.a.e type exhibited by the meta.. The obta.ned results indica.e tha. the hydrogen sulfide is the most a.tive ga. in the corrosion processes tha. took pla.e, quite a.ove ca.bon dioxide. The ma.n observed corrosion products were iron sulfides a.d the typica. da.a.e a.socia.ed with hydrogen sulfide presence wa. Sulfide Stress Cra.king (SSC). The surfa.e da.a.e evidences the presence of cra.ks with considera.le ma.nitude a.d meta. loss a. consequences of the corrosion processes. Likewise, the presence of oxygen in the system modifies the displa.ed corrosion type, where corrosion products such a. iron oxides a.d reduction in the number a.d extent of cra.ks a.e observed. On the other ha.d, the a.dition of a.film-forming corrosion inhibitor ba.ed on modified imida.olines elimina.es completely the development of cra.ks, a.though under certa.n test conditions, it ca. fa.or loca.ized pitting corrosion.

关键词： h2S Corrosion Cra.king Corrosion Inhibition

Loss of ta. expression a.tenua.es neurodegenera.ion a.socia.ed with α-synucleinopa.hy

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Tra.sla.iona. Neurodegenera.ion 2022年第1期11卷 426-442页

作者： Scott C.Vermilyea.a.ne Christensen Joyce Meints Ba.vinda. Singh h.ctor Ma.tell-Ma.tínez MdRa.a.l Ka.im Micha.l K.Lee Depa.tment of Neuroscience University of Minnesota-Twin Cities321 Church Street S.E.MinneapolisMNUSA6-145 Jackson Hall Institute for Tra.sla.iona. Neuroscience University of Minnesota-Twin CitiesMin-neapolisMNUSA a.igning Science a.ross Pa.kinson’s(a.a.)Colla.ora.ive Resea.ch Network Chevy ChaseMDUSA University of Minnesota.Medica. School 420 Delaware Street SEMinneapolisMN 55455USA.

Ba.kground: Neurona. dysfunction a.d degenera.ion linked to α-synuclein (αS) pa.hology is thought to be responsible for the progressive na.ure of Pa.kinson’s disea.e a.d rela.ed dementia.with Lewy bodies. Studies ha.e indica.ed bidirectiona. pa.hologica. rela.ionships between αS pa.hology a.d ta. a.norma.ities. We recently showed tha. a.3T muta.t huma. αS (huαS) ca. ca.se post-syna.tic a.d cognitive deficits tha. require microtubule-a.socia.ed protein ta. expression. however, the role of ta. in the development of αS pa.hology a.d subsequent neurona. dysfunction ha. been controversia.. herein, we set out to determine the role of ta. in the onset a.d progression of αS pa.hology (α-synucleinopa.hy) using a.tra.sgenic mouse model of α-synucleinopa.hy la.king mouse ta. expression. Methods: Tra.sgenic mice expressing a.3T muta.t huαS (Tga.3T) were crossed with mTa.−/− mice to genera.e Tga.3T/mTa.−/−. To a.hieve more uniform induction of α-synucleinopa.hy in mice, we used intra.uscula. injections of αS preformed fibrils (PFF) in non-tra.sgenic (nTg), Tga.3T, Tga.3T/mTa.−/−, a.d mTa.−/− mice. Motor beha.ior wa. a.a.yzed a. 70 da.s post inocula.ion (dpi) of PFF a.d tissues for biochemica. a.d neuropa.hologica. a.a.ysis were collected a. 40 dpi, 70 dpi, a.d end sta.e. Results: Loss of ta. expression significa.tly dela.ed the onset of motor deficits in the Tga.3T model a.d the progression of α-synucleinopa.hy disea.e, a. evidenced by a.significa.t reduction in histopa.hologica. a.d beha.iora. ma.kers of neurodegenera.ion a.d disea.e, a.d a.significa.t improvement in surviva.. In vitro a.plica.ion of PFF to prima.y mouse hippoca.pa. neurons demonstra.ed no cha.ges in PFF upta.e a.d processing or pS129 αS a.grega.ion a. a.function of ta. expression. however, PFF-induced neurotoxicity, including morphologica. deficits in nTg neurons, wa. prevented with ta. remova.. Conclusions: Collectively, our da.a.suggest tha. ta. is likely a.ting downstrea. of αS pa.hology to a.fect neurona.

关键词： α-Synuclein Ta. Pa.kinson’s disea.e Lewy body disea.e Neurodegenera.ion

Preva.ence of refra.tive errors in children of Puerto Rico

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Interna.iona. Journa. of Ophtha.mology(English edition) 2023年第3期16卷 434-441页

作者： h.ctor C.Sa.tia.o Ma.ra.Rullán Ka.erin Ortiz a.drés Rivera.Mónica.Nieves JoséPiña.Zulma.is Torres Yvette Merca.o Inter a.erica. University of Puerto Rico School of Optometry500 John Will HarrisBayamónPuerto Rico 00957USA

a.M:To determine the preva.ence of refra.tive error in 5-to 17-yea.-old schoolchildren in Puerto ***:a.qua.tita.ive descriptive study of 2867 children a.ed 5 to 17y from a.l seven educa.iona. regions of Puerto Rico wa. conducted from 2016–*** error wa. determined via.sta.ic a.d subjective *** with dista.ce a.uity≤20/40 or nea. visua. a.uity≤20/32 ha. a.cycloplegic *** a.a.ysis included descriptive sta.istics,correla.ion coefficient,Kruska.-Wa.lis,Chi-squa.e,a.d t test ***:Twenty percent of the children ha. a.spherica. equiva.ent refra.tive error≤-0.50 D,3.2%ha. a.spherica. equiva.ent≥+2.00 D,a.d 10.4%ha. a.tigma.ism≥1 *** wa. a.sta.istica.ly(but non-clinica.ly)significa.t myopic cha.ge in spherica. equiva.ent refra.tive error with a.e(Phe preva.ence of myopia.increa.ed with a.e(Phyperopia.P=0.59)or a.tigma.ism(P=0.51).Ma.es ha. a.significa.tly higher hyperopic spherica. equiva.ent tha. fema.es(Pa.es ha. a.higher preva.ence of myopia.Pha. ma.es,but there wa. no difference in the hyperopia.P=0.74)or a.tigma.ism preva.ence(P=0.87).CONCLUSION:The preva.ence of a.spherica. equiva.ent equa. to or less tha.-0.50 D(myopia.20.7%)is one of the highest a.ong simila.-a.ed children *** studies should explore the ra.e of myopia.progression in children in Puerto *** children must be monitored to exa.ine the need for trea.ment of myopia.progression.

关键词： children refra.tive error Puerto Rico myopia hyperopia