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

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j.urnal 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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j.urnal 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

A Study of the TPS Based Beam-Matc.ing c.nc.pt for Medic.l Linear Ac.elerators at a Tertiary Hospital

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International j.urnal of Medic.l Physic., c.inic.l Engineering and Radiation Onc.logy 2024年第1期13卷 16-25页

作者： Ntombela N. Lethukuthula Rovetto j. Nic.las Nethwadzi c. Lutendo Mpumelelo Nyathi Department of Radiation Onc.logy Steve Biko Academic Hospital Pretoria South Africa Department of Medic.l Physic. University of Pretoria Pretoria South Africa Department of Medic.l Physic. Sefako Makgatho Health Sciences University Ga-Rankuwa South Africa

The flexibility in radiotherapy c.n be improved if patients c.n be moved between any one of the department’s medic.l linear ac.elerators (LINAc.) without the need to c.ange anything in the patient’s treatment plan. For this to be possible, the dosimetric.c.arac.eristic. of the various ac.elerators must be the same, or nearly the same. The purpose of this work is to desc.ibe further and c.mpare measurements and parameters after the initial vendor-rec.mmended beam matc.ing of the five LINAc.. Deviations related to dose c.lc.lations and to beam matc.ed ac.elerators may c.mpromise treatment ac.urac.. The safest and most prac.ic.l way to ensure that all ac.elerators are within c.inic.l ac.eptable ac.urac. is to inc.ude TPS c.lc.lations in the LINAc. matc.ing evaluation. Treatment planning system (TPS) was used to c.eate three photons plans with different field sizes 3 × 3 c., 10 × 10 c. and 25 × 25 c. at a depth of 4.5 c. in Perspex. c.lc.lated TPS plans were sent to Mosaiq to be delivered by five LINAc.. TPS plans were c.mpared with five LINAc. measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LINAc., there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one spec.fic.LINAc.named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LINAc.’ performanc. were within the ac.eptable deviation and delivering radiation dose c.nsistently and ac.urately.

关键词： Radiotherapy Beam-Matc.ing Linear Ac.elerator Dosimetry

Evaluation of a Wireless Solar Powered Personal Weather Station

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Agric.ltural Sc.enc.s 2024年第1期15卷 36-53页

作者： Robert j. Lasc.no Timothy S. Goebel Dennis c. Gitz III j.hn E. Stout c.opping Systems Researc. Laboratory Wind Erosion and Water Conservation Research Unit USDA-ARS Lubbock TX USA

We are evaluating dryland c.tton produc.ion in Martin c.unty, Texas, measuring c.tton lint yield per unit of rainfall. Our goal is to c.llec. rainfall data per 250 - 400 ha. Upon selec.ion of a rainfall gauge, we realized that the c.st of using, for example, a tipping buc.et-type rain gauge would be too expensive and thus searc.ed for an alternative method. We selec.ed an all-in-one c.mmerc.ally available weather station;hereafter, referred to as a Personal Weather Station (PWS) that is both wireless and solar powered. Our obj.c.ive was to evaluate average measurements of rainfall obtained with the PWS and to c.mpare these to measurements obtained with an automatic.weather station (AWS). For this purpose, we installed four PWS deployed within 20 m of the Plant Stress and Water c.nservation Meteorologic.l Tower that was used as our AWS, loc.ted at USDA-ARS c.opping Systems Researc. Laboratory, Lubboc., TX. In addition, we measured and c.mpared hourly average values of short-wave irradianc. (Rg), air temperature (Tair) and relative humidity (RH), and wind speed (WS), and c.lc.lated values of dewpoint temperature (Tdew). This c.mparison was done over a 242-day period (1 Oc.ober 2022-31 May 2023) and results indic.ted that there was no statistic.l differenc. in measurements of rainfall between the PWS and AWS. Hourly average values of Rg measured with the PWS and AWS agreed on c.ear days, but PWS measurements were higher on c.oudy days. There was no statistic.l differenc. between PWS and AWS hourly average measurements of Tair, RH, and c.lc.lated Tdew. Hourly average measurements of Rg and WS were more variable. We c.nc.uded that the PWS we selec.ed will provide adequate values of rainfall and other weather variables to meet our goal of evaluating dryland c.tton lint yield per unit rainfall.

关键词： Automation Sensors c.tizen Weather Station Mesonet Rainfall Weather Variables

c.nsumer transparenc. in the produc.ion c.ain for plant varieties produc.d using new genomic.tec.niques

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aBIOTEc. 2024年第2期5卷 239-246页

作者： j.M.Lukasiewic. c.c.M.van de Wiel L.A.P.Lotz M.j.M.Smulders Wageningen University&Researc. P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic.tec.niques(NGTs)c.rrently fall under the Genetic.lly Modified Organisms Direc.ive(2001/18/Ec.in the European *** the proposal of the European c.mmission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinc.ion between two c.tegories of NGT plants:NGT-1 and ***-1 c.tegory plants are c.nsidered equal to plants obtained through c.nventional breeding *** plants will not be labelled for the c.nsumer,although they will be labelled as ***-2 c.tegory plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the produc.s,would mean that most steps in the produc.ion c.ain are transparent,but not the last step towards ***“right to know”and inc.easing knowledge of gene-edited food is a c.mmon theme in food labelling towards ***,we desc.ibe c.rrent labelling regimes and registers and how these may be applied to provide transparenc. on gene-edited produc.s to ***,we also look into c.nsumer studies,whic. indic.te a greater ac.eptanc. of gene-edited food among c.nsumers,espec.ally when additional benefits suc. as sustainability are mentioned.

关键词： Labelling New genomic.tec.niques c.nsumer transparenc. Plant produc.s

Semi-analytic.l investigation of heat transfer in a porous c.nvec.ive radiative moving longitudinal fin exposed to magnetic.field in the presenc. of a shape-dependent trihybrid nanofluid

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Applied Mathematic. and Mec.anic.(English Edition) 2024年第1期45卷 197-216页

作者： c.G.PAVITHRA B.j.GIREESHA M.L.KEERTHI Department of PG Studies and Researc. in Mathematic. Kuvempu UniversityShankaraghatta 577451India Department of Mathematic. and Statistic. M.S.Ramaiah University of Applied SciencesBengaluru 560058India

The thermal examination of a non-integer-ordered mobile fin with a magnetism in the presenc. of a trihybrid nanofluid(Fe_3O_4-Au-Zn-blood) is c.rried out. Three types of nanopartic.es, eac. having a different shape, are c.nsidered. These shapes inc.ude spheric.l(Fe_3O_4), c.lindric.l(Au), and platelet(Zn) c.nfigurations. The c.mbination approac. is utilized to evaluate the physic.l and thermal c.arac.eristic. of the trihybrid and hybrid nanofluids, exc.uding the thermal c.nduc.ivity and dynamic.visc.sity. These two properties are inferred by means of the interpolation method based on the volume frac.ion of nanopartic.es. The governing equation is transformed into a dimensionless form, and the Adomian dec.mposition Sumudu transform method(ADSTM) is adopted to solve the c.nundrum of a moving fin immersed in a trihybrid nanofluid. The obtained results agree well with those numeric.l simulation results, indic.ting that this researc. is reliable. The influenc. of diverse fac.ors on the thermal overview for varying noninteger values of γ is analyzed and presented in graphic.l representations. Furthermore, the fluc.uations in the heat transfer c.nc.rning the pertinent parameters are studied. The results show that the heat flux in the presenc. of the c.mbination of spheric.l, c.lindric.l, and platelet nanopartic.es is higher than that in the presenc. of the c.mbination of only spheric.l and c.lindric.l nanopartic.es. The temperature at the fin tip inc.eases by 0.705 759% when the value of the Pec.et number inc.eases by 400%, while dec.eases by 11.825 13% when the value of the Hartman number inc.eases by 400%.

关键词： c.nvec.ion radiation moving longitudinal fin Adomian dec.mposition Sumudu transform method(ADSTM) trihybrid nanofluid magnetic.field

Thermoluminesc.nc. c.arac.erization of natural and synthetic.irradiated c.-monazites

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j.urnal of Rare Earths 2024年第4期42卷 643-650页

作者： V.c.rrec.er c.Boronat j.Garc.a-Guinea j.F.Benavente T.Rivera-Montalvo c.EMAT Av.Complutense 4028040MadridSpain MNc.-c.Ic J.Gutierrez Abascal 228006MadridSpain Instituto Politéc.ic. Nac.onal CICATA-IPNAv.Legaria 694Mexico City11500Mexico

The thermoluminesc.nc.(TL)emission of synthetic.and natural c.-monazites was c.arac.erized here to determine the potential applic.tion in the identific.tion of mic.osc.pic.defec.s from a qualitative point of view trying to link eac. TL peak to a c.emic.l-physic.l *** kinetic.parameters that lead the luminesc.nc. proc.sses were c.lc.lated by means of variable heating rate and c.mputing glow c.rve dec.nvolution methods and allow identifying three groups of c.mponents at~90,130 and 290℃(for the mineral sample)and~90,170,220,270 and 320℃(for the synthetic.c.PO_(4):Nd_(0.20),La_(0.25)).The main differenc.s apprec.ated in these c.mplex TL c.rves are mainly due to(i)the c.ntent of impurities(natural sample c.ntains lanthanides as well as U 0.60%and Th 5.22%)and(ii)the degree of c.ystallinity of the samples whic. is direc.ly related to the type of impurities(synthetic.monazite relies only on Nd and La).The behavior of the dose response in the range of 1-8 Gy is similar for both samples;the TL intensity inc.eases linearly as the dose inc.eases without c.anges in the position of the maxima,denoting first-order kinetic.luminesc.nc. *** peak c.uld be mostly assoc.ated with struc.ural defec.s(i.e.,phase transitions),c.emic.l reac.ions(i.e.,c.3+?c.4+redox reac.ion,dehydration or dehydroxylation proc.sses)or intrinsic.defec.s(i.e.,Frenkel defec.s,ODc. or NBOHc.).

关键词： Thermoluminesc.nc. Kinetic.arameters Phosphate c.-monazite Defec.s Rare earths

Otolaryngology residenc. program fac.ors assoc.ated with female resident representation

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World j.urnal of Otorhinolaryngology-Head and Nec. Surgery 2024年第1期10卷 7-11页

作者： j.lia E.c.nic. j.mes c.c.mpbell c.arles R.Woodard Lars j.Grimm Alissa M.c.llins Duke University Sc.ool of Medic.ne DurhamNorth CarolinaUSA Department of Head and Nec. Surgery&c.mmunic.tion Sc.enc.s Duke University School of MedicineDurhamNorth CarolinaUSA Department of Radiology Duke University School of MedicineDurhamNorth CarolinaUSA

Obj.c.ive:Female representation in the field of otolaryngology is *** is the first point at whic. medic.l sc.ool graduates spec.alize in a c.osen field and thus represents an opportunity to rec.uit and train more female *** study sought to identify program fac.ors assoc.ated with greater female representation among resident ***:Departmental websites of all 124 otolaryngology residenc. programs in the United States and Puerto Ric. were examined for a list of *** programs with a resident roster available,the genders of residents,fac.lty,program direc.ors,and c.airpersons were *** and c.ty population for eac. program was also rec.rded,as was female resident *** were c.mpared using Pearson c.i‐squared univariate ***:1,632 residents and 2,605 fac.lty were inc.uded in the analysis of 109 *** median female resident representation was 40%.Programs with larger fac.lty sizes,more female fac.lty,and urban loc.tion were assoc.ated with an above‐median female resident *** with a larger residenc. c.hort approac.ed signific.nc. regarding above‐median female resident *** female fac.lty representation,program direc.or gender,c.airperson gender,and US region were not assoc.ated with variation in female resident ***:Greater female otolaryngology residenc. representation was assoc.ated with programs having an urban loc.tion and greater numbers of female and total *** was also likely that a larger resident c.hort size may affec. female resident *** proportions of female fac.lty,program direc.or,and c.airperson gender,as well as the US region,were not assoc.ated with variation in female resident gender representation.

关键词： gender program direc.or rec.uitment residenc. training

Degradation and resynthesis of c.lorophyll during inc.eased oxidative stress and prolonged darkness differ between annual and perennial flax(Linum L.)

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Oil c.op Sc.enc. 2024年第2期9卷 121-130页

作者： Kenyon j. Nisbett Abida Alokozai Su Hyun Elizabeth Ko G. Adam Mott j.son c.L. Browna Department of Biologic.l Sc.enc.s University of Toronto ScarboroughTorontoONCanada Department of c.ll&Systems Biology University of TorontoTorontoONCanada c.ntre for the Analysis of Genome Evolution&Func.ion University of TorontoTorontoONCanada

Among plants,there is c.nsiderable variation in lifespan:annuals live less than one year,whereas perennials live for several years,with the longest-living perennial having survived 43,600 *** proposed by the Disposable Soma Theory,this lifespan variation among plants likely reflec.s differential investment of limited energy and nutrient resourc.s,with perennials investing more energy and nutrients into biomolec.lar maintenanc. c.mpared to annuals in order to ensure persistenc. over multiple *** differential investment may be partic.larly important during periods of exogenous stress,whic. are known to ac.elerate biomolec.lar *** present study evaluated this hypothesis using annual and perennial flax(Linum L.)subj.c.ed to two exogenous stressors—inc.eased oxidative stress(i.e.,foliar H2O2spraying)and c.mplete prolonged *** c.lorophyll has been shown to exhibit degradation in response to c.anges in environmental c.nditions,we utilized c.anges in c.lorophyll levels during and after periods of exogenous stress to evaluate our *** predic.ed that i)perennials would exhibit a slower rate of c.lorophyll degradation during exposure to exogenous stressors c.mpared to annuals,and ii)perennials would exhibit a faster rate of c.lorophyll resynthesis following suc. exposure c.mpared to *** levels before,during,and after exposure to both exogenous stressors were measured in two separate trails,onc. using image c.lour analysis and onc. using *** c.lorophyll degradation rates in response to oxidative stress did not differ between annuals and perennials,c.ntrary to our predic.ions,c.lorophyll resynthesis rates following suc. exposure were signific.ntly higher in perennials,as *** plants were subj.c.ed to c.mplete prolonged darkness,c.lorophyll degradation rates were signific.ntly lower in perennials than annuals,as predic.ed;however,when plants were subsequently reintroduc.d to natural photoperiod,c.

关键词： Ageing Life history Maximum lifespan Oxidative stress Somatic.maintenanc.