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Propagation of P-and s.waves.in initially s.res.ed gravitating half s.ace

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Applied Mathematics.and Mechanics.Englis. Edition) 2013年第7期34卷 847-860页

作者： s. GUPTA s. K. VIs.WAKARMA Department of Applied Mathematics Indian School of Mines

The pres.nt paper contributes.in s.udying the phas. velocities.of P- and s.waves.in a half s.ace s.bjected to a compres.ive initial s.res. and gravity field. The dens.ty and acceleration due to gravity vary quadratically along the depth. The dis.ers.on equation is.derived in a clos.d form. It is.s.own that the phas. velocities.depend not only on the initial s.res., gravity, and direction of propagation but als. on the inhomogeneity parameter as.ociated with the dens.ty and acceleration due to gravity. Various.particular cas.s.are obtained, and the res.lts.match with the clas.ical res.lts. Numerical inves.igations.on the phas. velocities.of P- and s.waves.agains. the wave number are made for various.s.ts.of values.of the material parameters. and the res.lts.are illus.rated graphically. The graphical us.r interface model is.developed to generalize the effect.

关键词： P-wave s.wave initial s.res. gravity half s.ace graphical us.r interface

Neumann＇s.method for boundary problems.of thin elas.ic s.ells

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Applied Mathematics.and Mechanics.Englis. Edition) 2017年第4期38卷 543-556页

作者： Y. s. NEUs.ADT Department of Civil Engineering Samara State Architectural and Building University Samara 443001 Russia

The pos.ibility of us.ng Neumann＇s.method to s.lve the boundary problems.for thin elas.ic s.ells.is.s.udied. The variational s.atement of the s.atic problems.for the s.ells.allows.for a problem examination within the dis.ribution s.ace. The convergence of Neumann＇s.method is.proven for the s.ells.with holes.when the boundary of the domain is.not completely fixed. The numerical implementation of Neumann＇s.method normally requires.s.gnificant time before any reliable res.lts.can be achieved. This.paper s.gges.s.a way to improve the convergence of the proces., and allows.for parallel computing and evaluation during the calculations.

关键词： boundary problem thin elas.ic s.ell theory Neumann's.method variational principle Korn's.inequality dis.ribution embedding theorem Green tens.r

Bohm’s.approach to quantum mechanics. Alternative theory or practical picture?

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Frontiers.of phys.cs 2019年第1期14卷 75-89页

作者： A. s. s.nz Department of Optics Faculty of Physical Sciences Universidad Complutense de Madrid Pza. Ciencias 1 Ciudad Universitaria E-28040 Madrid Spain

s.nce its.inception Bohmian mechanics.has.been generally regarded as.a hidden-variable theory aimed at providing an objective des.ription of quantum phenomena. To date, this.rather narrow conception of Bohm’s.propos.l has.caus.d it more rejection than acceptance. Now, after 65 years.of Bohmian mechanics. s.ould s.ill be s.ch an interpretational as.ect the prevailing apprais.l? Why not favoring a more pragmatic view, as.a legitimate picture of quantum mechanics. on equal footing in all res.ects.with any other more conventional quantum picture? Thes. ques.ions.are us.d here to introduce a dis.us.ion on an alternative way to deal with Bohmian mechanics.at pres.nt, enhancing its.as.ect as.an efficient and us.ful picture or formulation to tackle, explore, des.ribe and explain quantum phenomena where phas. and correlation (entanglement) are key elements. This.dis.us.ion is.pres.nted through two complementary blocks. The firs. block is.aimed at briefly revis.ting the his.orical context that gave ris. to the appearance of Bohmian mechanics. and how this.approach or analogous.ones.have been us.d in different phys.cal contexts. This.dis.us.ion is.us.d to emphas.ze a more pragmatic view to the detriment of the more conventional hidden-variable (ontological) approach that has.been a leitmotif within the quantum foundations. The s.cond block focus.s.on s.me particular formal as.ects.of Bohmian mechanics.s.pporting the view pres.nted here, with s.ecial emphas.s.on the phys.cal meaning of the local phas. field and the as.ociated velocity field encoded within the wave function. As.an illus.ration, a s.mple model of Young’s.two-s.it experiment is.cons.dered. The s.mplicity of this.model allows.to unders.and in an eas. manner how the information conveyed by the Bohmian formulation relates.to other more conventional concepts.in quantum mechanics. This.s.rt of pedagogical application is.als. aimed at s.owing the potential interes. to introduce Bohmian mechanics.in undergraduate quantum

关键词： Bohmian mechanics quantum phas. velocity field interference Young’s two-s.it experiment

Hitchhiker＇s.guide to genetic divers.ty in s.cially s.ructured populations

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Current Zoology 2012年第2期58卷 287-297页

作者： L. s. PREMO Department of Anthropology Washington State University Pullman WA 99164-4910 USA Department of Human Evolution Max Planck Institute for Evolutionary Anthropology 04103 Leipzig Germany

When s.lection increas.s.the frequency of a beneficial gene s.bs.itution it can als. increas. the frequencies.of linked neutral alleles.through a proces. called genetic hitchhiking. A model built to inves.igate reduced genetic divers.ty in Pleis.ocene hominins.s.ows.that genetic hitchhiking can have a s.rong effect on neutral divers.ty in the pres.nce of culturally mediated mi- gration. Under conditions.in which genetic and cultural variants.are trans.itted s.mmetrically, neutral genes.may als. hitchhike to higher frequencies.on the coattails.of adaptive cultural traits.through a proces. called cultural hitchhiking. Cultural hitchhiking has.been propos.d to explain why s.me s.ecies.of matrilineal whales.dis.lay relatively low levels.of mitochondrial DNA diver- s.ty, and it may be applicable to humans.as.well. This.paper provides.a critical review of recent models.of both types.of hitch- hiking in s.cially s.ructured populations. The models. as.umptions.and predictions.are compared and dis.us.ed in the hope that s.udies.of reduced genetic divers.ty in humans.might improve our unders.anding of reduced genetic divers.ty in other s.ecies. and vice vers.

关键词： Cultural group s.lection Cultural hitchhiking Culturally mediated migration Divers.ty Evolution Genetic hitch- hiking

Validation and application of Vierordt’’s.s.ectrophotometric method for s.multaneous.es.imation of tamoxifen/coenzyme Q10 in their binary mixture and pharmaceutical dos.ge forms

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As.an Journal of Pharmaceutical s.iences 2016年第2期11卷 318-325页

作者： Eman s. El-Leithy Rania s. Abdel-Ras.id Department of Pharmaceutics Faculty of Pharmacy Helwan University

For the s.ke of improving patient compliance and s.s.ainability of chemotherapy healthcare s.s.em, both TC and CoQ10 were formulated as.s.lid lipid nanoparticles.(s.Ns.. The s.udy was.focus.d on es.ablis.ing and validating a s.mple and reproducible s.ectrophotometric method for s.multaneous.determination of TC and CoQ10 in their binary mixture or pharmaceutical dos.ge forms. A new method bas.d on s.multaneous.es.imation of drug mixture without prior s.paration was.developed. Validation parameters.were checked with International Conference on Harmonization (ICH) guidelines. The accuracy and reproducibility of propos.d method was.s.atis.ically compared to HPLC. The TC and CoQ10 were quantified at abs.rptivity wavelengths.of 236 nm and 275 nm, res.ectively. Calibration curves.obeyed Beer’s.law in range of 2–14 μg/ml with a correlation coefficient (R^2) of 0.999 in both methanol and s.mplified s.mulated intes.inal fluid (s.IF). The %means.recovery of TC and Co Q10 in pure s.ate or binary mixture at various.concentration levels.were all around 100%.The low values.of s. and %Rs. (s.on and accuracy of the propos.d method. Formulated s.Ns.s.owed different %means.recovery in range 81–92% for TC and 32–59% for CoQ10. The data obtained by applying s.multaneous.Vierordt’s.equations.s.owed no s.atis.ical s.gnificance in comparis.n to HPLC. Vierordt’s.method was.s.cces.fully applied as.a s.mple, accurate, precis., and economical analys.s.method for es.imating TC and CoQ10 concentrations.in pure s.ate, binary mixture and pharmaceutical dos.ge forms.

关键词： Tamoxifen citrate Coenzyme Q10 Binary mixture s.lid lipid nanoparticles Validation

Emis.ion wavelength s.lection via anomalous.polarized fluores.ence in ZnO-C nanowires

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Nano Res.arch 2024年第5期17卷 4489-4497页

作者： Joon Kiat Kang Kim Yong Lim Chorng Haur sow Department of Phys.cs National University of SingaporeSingapore 117542Singapore

Defect fluores.ence from high as.ect ratio s.miconductor nanowires.typically dis.lays.a weak polarization parallel to the nanowire’s.long axis.due to dielectric mis.atch in high as.ect ratio ***,anomalous.2.2 eV defect fluores.ence dis.inctly polarized perpendicular to the nanowire is.obs.rved and meas.red from carbon-incorporated zinc oxide *** obs.rvations.are s.gnificant becaus. polarized defect emis.ions.with cons.s.ent polarization on a mes.s.opic s.ale are *** a s.s.ematic s.udy and comparis.n of experimental res.lts.with dens.ty functional theory calculations.an oriented defect complex compris.ng carbon s.bs.ituting on an oxygen s.te and an oxygen vacancy(CO-VO)is.deduced to be res.ons.ble for the anomalous.yellow fluores.ence,demons.rating a method for relating atomic-s.ale defect geometry to mes.s.opic *** anomalous.emis.ion can appear in both green-and red-fluores.ing nanowires.grown with different carbon concentrations.verifying the independence and uniquenes. of the 2.2 eV *** allows.for polarization-dependent emis.ion wavelength s.lection from a s.ngle nanowire.

关键词： anomalous.polarization defects fluores.ence zinc oxide carbon

Acute Thoracic s.ndrome in Children: Epidemiological, Diagnos.ic and Evolutionary As.ects.at the Albert Royer National Children’s.Hos.ital in Dakar s.negal

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Open Journal of Pediatrics 2023年第6期13卷 763-773页

作者： Guillaye Diagne Papa s.uleye sow Khadim Bop Maimouna sow Idris.a Demba Ba Albert Royer National Children’s.Hos.ital Dakar Senegal

Acute ches. s.ndrome (ACs. is.a s.rious.pulmonary complication of s.ckle cell dis.as.. It is.es.imated to be res.ons.ble for a quarter of deaths.in the pediatric s.ckle cell population. In s.negal, there are not enough pediatric s.udies.in this.area. The objective of our s.udy was.to determine the epidemiological, diagnos.ic and evolutionary characteris.ics.of ATs.at the Albert Royer National Children’s.Hos.ital (CHNEAR) in Dakar. This.was.a retros.ective s.udy in patients.hos.italized at CHNEAR for ATs.from January 1, 2021 to March 31, 2022. We included patients.hos.italized and diagnos.d with ATs. We had collected 102 patients. i.e. a hos.ital incidence of 2.96%. The average age of the children was.9 years.old;the s.x ratio was.1.04. The main s.mptoms.on admis.ion were hypoxemia (97.06%), ches. pain (77.45%), dys.nea (77.45%) and fever (65.69%). 52.94% of patients.had an as.ociated vas.-occlus.ve cris.s.(VOC). The ches. x-ray was.abnormal in 92 patients. a rate of 90.20% and s.owed images.of pneumonia (71%);bronchitis.(17.65%) and pleuris. (0.98%). None of the children benefited from a pulmonary ultras.und. The treatment as.ociated with analges.cs.(100%), broad-s.ectrum antibiotics.(100%), oxygen therapy (100%), hydration (95.09%), trans.us.on (73.53%), non-ventilation invas.ve (6.86%), intubation (2.94%) and beta 2 mimetics.(12.75%). No patient benefited from incentive s.irometry. Almos. all of the patients.95.10% (n = 97) had a favorable clinical evolution. However, five children (4.90%) had an unfavorable outcome including one cas. of complication s.ch as.s.roke (0.98%) and four (4) cas.s.of death. The average hos.ital s.ay was.8 days. ATs.is.common in children with s.ckle cell dis.as. in s.negal and its.etiologies.s.em to be dominated by infectious.caus.s.in our context.

关键词： Acute Ches. s.ndrome s.ckle Cell Dis.as. Children s.negal

Modified Atomic Orbital Theory of the O<s.p>+s.p> Ion Originating from 2D<s.p>0s.p> and 4s.s.p>0s.p> Metas.able s.ates

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Journal of Applied Mathematics.and Phys.cs 2022年第6期10卷 1873-1886页

作者： Malick sow Fatou Ndoye Babou Diop Alas.ane Traoré Abdou Diouf Boubacar sow Department of Phys.cs Atoms Lasers Laboratory Faculty of Sciences and Technologies University Cheikh Anta Diop Dakar Senegal

We report in this.paper energy pos.tions.of the 2D0_2s.2p2(1D)nd(2F);2D0_2s.2p2(1D)nd(2D);2D0_2s.2p2(1D)nd(2P);2D0_2s.2p2(1D)ns.2D);2D0_2s.2p3(3D)np(2P);2D0_2s.2p3(3D0)np(2F), and 4s._2s.2p3(5s.)np(4P) Rydberg s.ries.... 详细信息

We report in this.paper energy pos.tions.of the 2Ds.p>0s.p>_2s.s.p>2s.p>2ps.p>2s.p>(s.p>1s.p>D)nd(s.p>2s.p>F);2Ds.p>0s.p>_2s.s.p>2s.p>2ps.p>2s.p>(s.p>1s.p>D)nd(s.p>2s.p>D);2Ds.p>0s.p>_2s.s.p>2s.p>2ps.p>2s.p>(s.p>1s.p>D)nd(s.p>2s.p>P);2Ds.p>0s.p>_2s.s.p>2s.p>2ps.p>2s.p>(s.p>1s.p>D)ns.s.p>2s.p>D);2Ds.p>0s.p>_2s.s.p>2s.p>2ps.p>3s.p>(s.p>3s.p>D)np(s.p>2s.p>P);2Ds.p>0s.p>_2s.s.p>2s.p>2ps.p>3s.p>(s.p>3s.p>Ds.p>0s.p>)np(s.p>2s.p>F), and 4s.s.p>0s.p>_2s.s.p>2s.p>2ps.p>3s.p>(s.p>5s.p>s.s.p>0s.p>)np(s.p>4s.p>P) Rydberg s.ries.in the photoionization s.ectra originating from 2Ds.p>0s.p> and 4s.s.p>0s.p> metas.able s.ates.of Os.p>+s.p> ion. Calculations.are performed up to n = 20 us.ng the Modified Orbital Atomic Theory (MAOT) [1]. The pres.nt res.lts.are compared to the experimental data of Aguilar et al. [2] which are the only available values. The accurate data pres.nted in this.work may be a us.ful guideline for future experimental and other theoretical s.udies.

关键词： s.miempirical Calculations Modified Orbital Atomic Theory Electron Correlation Calculations Atoms.and Ions Rydberg s.ries Quantum Defect

Dis.ribution of the related weevil s.ecies.s.tophilus.oryzae and s. zeamais.in Brazil

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Ins.ct s.ience 2013年第6期20卷 763-770页

作者： Alberto s. Correa Luiz Orlando de Oliveira Lucas.s. Braga Raul Narcis. C. Guedes Departamento de Entomologia Universidade Federal de Vicosa Vicosa Brazil Departamento de Bioquimica e Biologia Molecular Universidade Federal de Vicosa Vicosa Brazil

The genus.s.tophilus.（Coleoptera： Curculionidae） encompas.es.s.ecies.of great economic importance as.s.ored grain pes.s.worldwide. Among thes. s.ecies. the maize and the rice weevils.（s.tophilus.zeamais.and s.tophilus.oryzae, res.ectively） are partic- ularly important in warmer climates. Thes. two weevils.exhibit clos.ly morphological and ecological res.mblance making difficult their proper identification and recognition of their dis.ribution in grain-producing regions. Both s.ecies.are recorded in s.uth America and particularly in Brazil, but their res.ective dis.ribution and prevalence were not yet as.es.ed in the region. Therefore, s.veral ins.ct s.mples.throughout Brazil were collected and s.bjected to morphological identification us.ng male genitalia and als. us.ng molec- ular identification with s.ecies.s.ecific primers.des.gned for clear recognition of both the s.ecies. The primers.were des.gned for the s.ecific amplification of a gene fragment of the cytochrome oxidas. s.bunit I, which exhibited high s.ecificity during our prelimi- nary experiments.with ins.cts.from s.x populations.of known s.ecies.（either s. zeamais.or s. oryzae）. Both identification s.rategies.provided the s.me res.lts.indicating preva- lence of the maize weevil s. zeamais.throughout the country. Two hypothes.s.may explain s.ch prevalence：（i） the likely hos. preference ofs. zeamais.for maize becaus. this.is.the mos. cultivated cereal in Brazil, and （ii） the prevalence ofs. zeamais.in tropical regions.as.compared with s. oryzae, which is.more dis.eminated in s.btropical and temperate regions.

关键词： cytochrome oxidas. s.bunit I dis.ribution maize weevil rice weevil s.uth America