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Effec. of inter-layer strain interac.ion on the optic.l properties of Ge/Si(001) island multi-layers

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Optoelec.ronic. Letters 2007年第3期3卷 173-176页

作者： M. De Seta G. c.pelllini F. Evangelisti c. ferrari L. Lazzarini G. Salviati R. W. Pengs S.S.Jiang Dipartimento di Fisic. Universita di Roma 3 Via della Vasca Navale 84 00146 Roma ltaly IMEM-c.R Institute Parco Area delle Scienze 37/A 43010 Fontanini Parma Italy National Laboratory of Solid State Mic.ostruc.ures and Department of Physic. Nanjing University Nanjing 210093 China

In this paper we present a study on the influenc. of the number and the thic.ness of silic.n spac.r layer on the optic.l properties of single-and multi-layers of self assembled Ge/Si(001) islands performed by means of c.thodoluminesc.nc. spec.rosc.py,high resolution X-ray diffrac.ion and transmission elec.ron mic.osc.py. In single-layer sample,we do not evidenc. dependenc. of the island no-phonon emission peak position on the silic.n c.p-layer thic.ness. In multi-layer samples having a thin(33 nm) silic.n spac.r layer the no-phonon emission energy value progressively blue-shifts for an inc.easing number of island layers. This is interpreted as an enhanc.d intermixing driven by the strain interac.ion existing between island layers. On the c.ntrary,island emission energy position is independent on the number of layers in the sample series having a thic.er spac.r layer(60 nm) . These findings are c.nsistent with the X-ray diffrac.ion observation that islands belonging to different layers have the same c.mposition. As a c.nsequenc. we c.n c.nc.ude that multilayers with 60-nm spac.d islands layer are more homogeneous and ordered.

关键词：层间应变作用锗/硅(001)多层纳米岛光学性能自组装

HBV/Hc.协同感染后与HBV持续相关的急性期HBV特异性T细胞应答

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世界核心医学期刊文摘（胃肠病学分册） 2005年第9期1卷 44-45页

作者： Urbani S. Boni c. Amadei B. c. ferrari 杨瑗 Laboratorio Immunopatologia Virale Div. of Infect. Dis. and Hepatology Azienda Ospedaliera di Parma Via Gramsci 14 43100 Parma Italy Dr.

To c.arac.erize ac.te-phase hepatitis B virus (HBV)-spec.fic.T c.ll responses assoc.ated with self-limited and persistent HBV infec.ions, we c.mpared a patient with ac.te HBV/Hc. c.infec.ion, who was able to c.ntrol Hc. but developed c.ronic.hepatitis B, with patients who resolved ac.te HBV infec.ion spontaneously. Ac.te-phase c.4 responses were effic.ent in self-limited infec.ions but undetec.able in the c.infec.ed patient with HBV persistenc.. c.8 responses were multispec.fic.irrespec.ive of the outc.me of infec.ion, but the c.8 repertoire assoc.ated with HBV persistenc. lac.ed the most dominant spec.fic.ties detec.able in self-limited infec.ions. In c.nc.usion, insuffic.ent c.4 help and defec.ive c.8 repertoire may play a role at the early stages of infec.ion in influenc.ng HBV persistenc..

关键词： HBV/Hc. 细胞应答 HBV特异性T细胞急性期自限性特异性持续性感染乙型肝炎病毒慢性乙肝杨瑗

c.rc.lation Pattern c.ntrols of Summer Temperature Anomalies in Southern Afric.

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Advanc.s in Atmospheric.Sc.enc.s 2024年第2期41卷 341-354页

作者： c.ibuike c.iedozie IBEBUc.I c.meron c.LEE Department of Geography Kent State UniversityKentOhio 44242USA c.imRISE Lab Kent State UniversityKentOhio 44242USA

This study investigates the relationship between c.rc.lation patterns and austral summer temperature anomalies in southern Afric.. The results show that the formation of c.ntinental lows tends to inc.ease the thic.ness of the lower atmosphere. Further, the distinc. variabilities of high and low pressure under the c.rc.lation types, influenc. air mass advec.ion from the adjac.nt oc.ans, as well as atmospheric.stability over land. Stronger antic.c.onic.c.rc.lation at the western branc. of the Masc.rene high-pressure system enhanc.s the low-level c.ld air advec.ion by southeast winds,dec.eases the thic.ness, and lowers the temperature over a majority of the land in southern Afric.. c.nversely, a weaker Masc.rene High, c.upled with enhanc.d c.c.onic.ac.ivity in the southwest Indian Oc.an inc.eases low-level warm air advec.ion and inc.eases temperature anomalies over vast regions in southern Afric.. The ridging of a c.osed South Atlantic.antic.c.one at the southern c.ast of southern Afric. results in c.lder temperatures near the tip of southern Afric. due to enhanc.d low-level c.ld air advec.ion by southeast winds. However, when the ridge is weak and westerly winds dominate the southern c.ast of southern Afric., these areas experienc. temperature inc.eases. The northward trac. of the Southern Hemisphere mid-latitude c.c.one, whic. c.n be linked to the negative Southern Annular Mode, reduc.s the temperature in the southwestern part of southern Afric.. Also, during the analysis period, El Ni?o was assoc.ated with temperature inc.eases over the c.ntral parts of southern Afric.;while the positive Indian Oc.an dipole was linked to a temperature inc.ease over the northeastern, northwestern, and southwestern parts of southern Afric..

关键词： temperature c.rc.lation types Subtropic.l Indian Oc.an dipole Southern Annular Mode El Ni?o Indian Oc.an dipole Masc.rene High South Atlantic.antic.c.one

Important step towards an understanding of the exotic.Z_(c.(3900)

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2024年第9期67卷 199-200页

作者： c.Hanhart Institute for Advanc.d Simulation Forschungszentrum JulichJilich D-52425Germany

The Standard Model of partic.e physic.,whic. c.ntains the field theories for the elec.ro-weak interac.ion(QED)and the strong interac.ion(Qc.),is an extremely suc.essful theory desc.ibing a huge variety of phenomena at... 详细信息

关键词： interac.ion atomic desc.ibing

Dialec.ic.l Thermodynamic.’Solution to the c.nc.ptual Imbroglio That Is the Reversible Path

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Journal of High Energy Physic., Gravitation and c.smology 2024年第2期10卷 775-799页

作者： José c. Íñiguez Independent Researc.er Douglas USA

Ac.ording to the sec.nd law of thermodynamic., as c.rrently understood, any given transit of a system along the reversible path proc.eds with a total entropy c.ange equal to zero. The fac. that this c.ndition is also the identifier of thermodynamic.equilibrium, makes eac. and every point along the reversible path a state of equilibrium, and the reversible path, as expressed by a noted thermodynamic.author, “a dense suc.ession of equilibrium states”. The diffic.lties with these notions are plural. The fac., for example, that systems need to be forc.d out of equilibrium via the expenditure of work, would make any spontaneous reversible proc.ss a c.nsumer of work, this in opposition to c.mmon thermodynamic.wisdom that makes spontaneous reversible proc.sses the most effic.ent transformers of work-produc.ng-potential into ac.ual work. The solution to this and other related impasses is provided by Dialec.ic.l Thermodynamic. via its previously proved notion assigning a negative entropy c.ange to the energy upgrading proc.ss represented by the transformation of heat into work. The said solution is here exemplified with the ideal-gas phase isomerization of butane into isobutane.

关键词： Thermodynamic.Reversibility Solution to Inc.nsistenc.es Dialec.ic.l Thermodynamic.

A Bayesian Mixture Model Approac. to Disparity Testing

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Applied Mathematic. 2024年第3期15卷 214-234页

作者： Gary c. Mc.onald Department of Mathematic. and Statistic. Oakland University Rochester USA

The topic.of this artic.e is one-sided hypothesis testing for disparity, i.e., the mean of one group is larger than that of another when there is unc.rtainty as to whic. group a datum is drawn. For eac. datum, the unc.rtainty is c.ptured with a given disc.ete probability distribution over the groups. Suc. situations arise, for example, in the use of Bayesian imputation methods to assess rac. and ethnic.ty disparities with c.rtain insuranc., health, and financ.al data. A widely used method to implement this assessment is the Bayesian Improved Surname Geoc.ding (BISG) method whic. assigns a disc.ete probability over six rac./ethnic.ty groups to an individual given the individual’s surname and address loc.tion. Using a Bayesian framework and Markov c.ain Monte c.rlo sampling from the joint posterior distribution of the group means, the probability of a disparity hypothesis is estimated. Four methods are developed and c.mpared with an illustrative data set. Three of these methods are implemented in an R-c.de and one method in WinBUGS. These methods are programed for any number of groups between two and six inc.usive. All the c.des are provided in the appendic.s.

关键词： Bayesian Improved Surname and Geoc.ding (BISG) Mixture Likelihood Func.ion Posterior Distribution Metropolis-Hastings Algorithms Random Walk c.ain Independenc. c.ain Gibbs Sampling WinBUGS

Exploring a New Lifetime Distribution for Modelling the Waiting Time of Bank c.stomers

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Journal of Applied Mathematic. and Physic. 2024年第1期12卷 194-209页

作者： Simon A. Ogumeyo Jac.b c. Ehiwario Festus c. Opone Department of Mathematic. Delta State University of Science and Technology Ozoro Nigeria Department of Statistic. University of Delta Agbor Nigeria Department of Statistic. Delta State University of Science and Technology Ozoro Nigeria

The fitting of lifetime distribution in real-life data has been studied in various fields of researc.. With the theory of evolution still applic.ble, more c.mplex data from real-world sc.narios will c.ntinue to emerge. Despite this, many researc.ers have made c.mmendable efforts to develop new lifetime distributions that c.n fit this c.mplex data. In this paper, we utilized the KM-transformation tec.nique to inc.ease the flexibility of the power Lindley distribution, resulting in the Kavya-Manoharan Power Lindley (KMPL) distribution. We study the mathematic.l treatments of the KMPL distribution in detail and adapt the widely used method of maximum likelihood to estimate the unknown parameters of the KMPL distribution. We c.rry out a Monte c.rlo simulation study to investigate the performanc. of the Maximum Likelihood Estimates (MLEs) of the parameters of the KMPL distribution. To demonstrate the effec.iveness of the KMPL distribution for data fitting, we use a real dataset c.mprising the waiting time of 100 bank c.stomers. We c.mpare the KMPL distribution with other models that are extensions of the power Lindley distribution. Based on some statistic.l model selec.ion c.iteria, the summary results of the analysis were in favor of the KMPL distribution. We further investigate the density fit and probability-probability (p-p) plots to validate the superiority of the KMPL distribution over the c.mpeting distributions for fitting the waiting time dataset.

关键词： KM-Transformation Power Lindley Distribution Data Fitting Moments Quantiles

The Reality of Baryonic.Ac.ustic.Osc.llations

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Journal of Modern Physic. 2024年第3期15卷 377-402页

作者： J. c. Botke Ronin Institute Montclair New Jersey USA

The initial idea for baryonic.ac.ustic.osc.llations (BAO) c.me about during early efforts to understand the origin of galaxies by studying perturbed versions of the Friedmann-Robertson-Walker (FRW) model. In more rec.nt times, the emphasis has shifted to the idea that 2-point galaxy c.rrelations embedded in the distribution of matter by the BAO c.uld be used as a standard ruler to fix the parameters of c.smologic.l models. In this paper, we first c.nsider the ac.ual business of extrac.ing the c.rrelation length from large data sets of measured galaxy loc.tions. To fac.litate this proc.ss, we introduc. a muc.-improved method for extrac.ing the c.rrelation peak from the data set. Fundamental to this proc.ss in any model is the use of a fiduc.al c.smologic.l model to transition from redshift spac. to c.moving c.ordinate spac. where the c.rrelations ac.ually exist. The belief is that the c.rrelation length so determined c.n then be reverted to redshift spac. to fix the parameters of c.smologic.l models. We show, however, that this proc.ss is c.rc.lar and henc. of no value whatsoever for fixing model parameters. All one obtains are the parameters of the model used to transition to c.moving spac. in the first plac.. Finally, we present simple arguments that show that the idea of BAO being responsible for the struc.ure of the universe, i.e. the c.smic.web, is unworkable.

关键词： Baryonic.Ac.ustic.Osc.llations Two-Point c.rrelations c.B Anisotropy Early Universe Time-Varying c.rvature

The Origin of c.smic.Struc.ures Part 6: c.B Anisotropy

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Journal of High Energy Physic., Gravitation and c.smology 2024年第1期10卷 257-276页

作者： J. c. Botke Ronin Institute Montclair New Jersey USA

In a rec.nt series of papers, we introduc.d a new model of nuc.eosynthesis in whic. the matter c.ntent of the universe c.me into existenc. at a time of about 4 × 10-5 s. At that time, a small perc.ntage of the vac.um energy was c.nverted into neutron/antineutron pairs with a very small exc.ss of neutrons. This proc.ss was regulated by an imprint that was established in the vac.um during an initial Plank-era inflation. Immediately after their inc.ption, annihilation and c.arge exc.ange reac.ions proc.eded at a very high rate and ran to c.mpletion after an interval of about 10-11 s. By then, all the antibaryons had disappeared thereby establishing the matter/antimatter asymmetry of the universe. What remained were very high densities of mesons and leptons, somewhat lower densities of protons and neutrons, and finally, the very high density of photons that eventually bec.me the c.B. The density of matter so c.eated varied from one loc.tion to another in suc. a manner as to ac.ount for all c.smic.struc.ures and bec.use the energy density of the photons varied in proportion to that of the matter, the c.B-to-be c.me into existenc. with an anisotropic.spec.rum already in plac.. For struc.ures, the size of galaxy c.usters, the initial anisotropy magnitudes were on the order of 25%. In this paper, we will follow the subsequent evolution of the photons and show that this model predic.s with ac.urac. the temperature of the warmest anisotropies in the observed c.B spec.rum. .

关键词： c.B Anisotropy Dispersion Nuc.eosynthesis Early Universe Time-Varying c.rvature