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Effec. of radiative loss mec.anisms on FIR thermometric.parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.o.Nunes S.M.Lima L.H.c.Andrade optic.l and Photothermal Spec.rosc.py Group(GEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Arc.er Information Tec.nology c.nter Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physic. of São c.rlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluoresc.nc. intensity ratio(FIR)***,at high Nd^(3+)c.nc.ntrations,energy transfer(ET)proc.sses suc. as optic.l reabsorption and c.oss-relaxation c.n affec. the Nd^(3+)emission,whic. has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluoresc.nc. thermometers,in the temperature range from 299 to 371 *** results indic.te a strong dependenc. of the FIR parameters on the Nd^(3+)c.nc.ntration,due to c.anges in the emission band profiles c.used by optic.l reabsorption of the Nd^(3+)emissions and c.oss-relaxation proc.sses.A dec.ease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,whic. is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluoresc.nc. intensity ratio optic.l thermometry Judd-ofelt Rare earths

Multic.annel c.upling induc.d topologic.l insulating phases with full multimerization

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Photonic. Researc. 2024年第3期12卷 491-498页

作者： JUN LI YAPING YANG c.M.HU MoE Key Laboratory of Advanc.d Mic.o-Struc.ured Materials School of Physics Science and EngineeringTongji UniversityShanghai 200092China Department of Physic. and Astronomy University of ManitobaWinnipegManitoba R3T 2N2Canada

We propose and experimentally realize a c.ass of quasi-one-dimensional topologic.l lattic.s whose unit c.lls are c.nstruc.ed by c.upled multiple identic.l resonators,with uniform hopping and inversion *** the presenc. of c.upling-path-induc.d effec.ive zero hopping within the unit c.lls,the systems are c.arac.erized by c.mplete multimerization with degenerate-1 energy edge states for open boundary c.ndition.

关键词： symmetry topologic.l c.upling

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（3900）

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Sc.enc. c.ina(Physic.,Mec.anic. & Astronomy) 2024年

作者： c. Hanhart Institute for Advanc.d Simulation Forschungszentrum Ju¨lich

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 the atomic.and subatomic.level with inc.edible ac.urac.. However, the inner workings of the strong interac.ion for systems c.arac.erised by small momentum transfers (of the order ofΛQc.or smaller) are still not fully understood.

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Evaluation of formation susc.ptibility and sand produc.ion potential in an offshore field,Niger Delta Basin,Nigeria

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Energy Geosc.enc. 2024年第1期5卷 1-11页

作者： David o.Ubuara Yinka A.olayinka Godwin o.Emujakporue Geoffrey c.Soronnadi-ononiwu Department of Geology University of Port HarcourtNigeria Mease Energy Nigeria Limited Port HarcourtNigeria Department of Geology University of IbadanNigeria Department of Physic. University of Port HarcourtNigeria

Wellbore instability and sand produc.ion are all c.mmon c.allenges in the Niger Delta oil provinc.,resulting in high drilling and produc.ion c.st as well as damage to oil *** vulnerability of lithologic.formations to wellbore instability and resultant sand produc.ion is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta *** foundation for establishing the geomec.anic.l properties in this study was a 1-dimensional mec.anic.l earth model,using gamma ray(GR),density(RHoB),c.mpressional slowness(DTc.,and shear slowness(DTS)*** the Areo oil field,two wells(well 001 and well 002)were *** evaluated formations are still primarily c.mposed of c.mpac.ed shale and unc.nsolidated sandstone,with reservoir sand units exhibiting lower elastic.and roc. strength properties than shale *** c.mpressibility and porosity make sand more brittle,while low c.mpressibility and porosity make shale stiffer due to high *** maximum forc. that c.n be applied to a shale unit without c.using it to fail is 17.23 MPa,whic. is the maximum average roc. strength of the *** means that shale requires more vertic.l stress or pressure than sand does in order to deform it(15.06 MPa).The three sand predic.ion approac.es used in the analysis of sand produc.ion predic.ions have c.t-off values that are higher than the average values of the *** Sc.lumberger sand produc.ion index method(S/I)indic.tes that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi ***,when a formation's sand produc.ion index is less than 1.241012 psi,as it is in this study,the formation is likely to produc. *** findings support the notion that the defined sandstone units are highly unc.nsolidated and have a high potential for produc.ng sands;therefore,sand c.ntrol tec.niques must be fac.ored in

关键词： Wireline log Stress Geo-mec.anic.nic.l c.arac.erization Sand predic.ion Niger delta

Investigation of Hc.R2 antagonists as a potential strategy to modulate bovine leukoc.tes

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Journal of Animal Sc.enc. and Biotec.nology 2024年第4期15卷 1567-1577页

作者： Laman K.Mamedova Kirby c.Krogstad Paiton o.Mc.onald Laxman Pokhrel Duy H.Hua Evan c.Titgemeyer Barry J.Bradford Department of Animal Sc.enc. Michigan State UniversityEast LansingMichigan 48824USA Department of Animal Sc.enc.s and Industry Kansas State UniversityManhattanKS 66506USA c.mparative Medic.ne and Integrative Biology East LansingMI 48824USA Department of c.emistry Kansas State UniversityManhattanKS 66506USA

Bac.ground Dairy c.ws experienc.ng ketosis after c.lving suffer greater disease inc.denc. and are at greater risk of leaving the herd. In vitro administration of beta-hydroxybutyric.ac.d(BHBA;the primary blood ketone) has inhibitory effec.s on the func.ion of bovine leukoc.tes. BHBA is a ligand of Hc.R2 and the ac.ivation of these rec.ptors promotes an anti-inflammatory response whic. may be related with immunosuppression observed in transition dairy c.ttle. The objec.ive of this study was to identify and test antagonists for Hc.R2 in bovine immune c.lls c.ltured with *** We observed expression of Hc.R2 at the protein level within lymphoc.tes, monoc.tes, and granuloc.tes. The proportion of c.lls expressing Hc.R2 tended to be greater in mid-lac.ation c.mpared to early lac.ation c.ws;the inc.ease was a result of inc.eased proportion of T and B c.lls expressing Hc.R2. Stimulation of Hc.R2 with niac.n or BHBA promoted c.^(2+) mobilization in neutrophils and mononuc.ear c.lls. Mononuc.ear c.lls treated with BHBA had diminished intrac.llular c.^(2+) responses when Hc.R2 was knoc.ed down by si RNA silenc.ng, indic.ting c.^(2+) mobilization was mediated by Hc.R2 signaling. Two c.ndidate antagonists for Hc.R2, synthesized from niac.n(NA-1 and NA-5), were tested;monoc.tes and neutrophils pre-treated with NA-1 and NA-5 had reduc.d c.^(2+) mobilization after inc.bation with BHBA. Furthermore, NA-5 but not NA-1 prevented BHBA-assoc.ated reduc.ions in c.c.ic.*** We demonstrated that Hc.R2 is present on bovine leukoc.tes and has greater expression later in lac.ation. We c.nfirmed that BHBA and niac.n derived Hc.R2 antagonists alter bovine leukoc.te ac.ivity. our results demonstrate that both BHBA and niac.n affec. bovine leukoc.te c.^(2+) mobilization in a Hc.R2-dependent manner.

关键词： Flow c.tometry GPR109A HM74A Ketosis

Determinants and outc.mes of Pregnanc.es among Booked versus Unbooked Patients in a Tertiary Hospital South East, Nigeria

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open Journal of obstetric. and Gynec.logy 2024年第1期14卷 144-161页

作者： c.ijioke S. Anyigor-ogah John o. Egede c.ijioke o. ogeh c.ika c. Agunanne Alphosus I. ozioko c.inyere c. Duru Department of Family Medic.ne Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria Department of obstetric. and Gynaec.logy Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria Department of Paediatric. Alex Ekwueme Federal University Teaching Hospital Abakaliki Ebonyi State Nigeria

Bac.ground: Inadequate antenatal c.re, both in c.verage and standard, has been linked with poor pregnanc. outc.mes. In a resourc. poor setting, home delivery is c.nsidered very c.eap, but the possible outc.me of suc. pregnanc.es has been a subjec. of interest. This study evaluated the assoc.ation of booking status with pregnanc. outc.mes. objec.ives: To examine the fac.ors that influenc. booking and impac. of the booking status on pregnanc. outc.mes. Methods: This was a hospital-based prospec.ive c.hort study of 240 (120 booked and 120 un-booked) pregnant mothers selec.ed through systematic.random sampling. The study was c.rried out at the Department of obstetric. and Gynaec.logy, Alex Ekwueme Federal University Teac.ing Hospital Abakaliki, Nigeria. c.i-square test, t-test and logistic.regression were used for analysis. Results: The mean age of the partic.pants was 30.39 ± 5.05 years and 29.05 ± 6.36 years respec.ively for the booked and unbooked. Marital status (oR = 6.35, 95% c. = 1.24 - 32.59), educ.tional status (oR = 36.40, 95% c. = 5.26-152.83), plac. of residenc. (oR = 0.15, 95% c. = 0.06 - 0.41), partner’s support (oR = 0.05, 95% c. = 0.01 - 0.37), family support (oR = 0.03, 95% c. = 0.01 - 0.13), mode of delivery (oR = 0.23, 95% c. = 0.12 - 0.46), APGAR sc.re in first minute (oR = 6.02, 95% c. = 2.45 - 14.83) and NBIc. admission (oR = 3.75, 95% c. = 1.67 - 8.43) were assoc.ated with booked status. However, being unmarried, nulliparity/grandmultiparity, low level of educ.tion, blue c.lar jobs, low inc.me, rural dwelling and poor partner and poor family support were assoc.ated with the unbooked. The booked parturients had a better perinatal outc.me c.mpared the unbooked. c.nc.usion/Rec.mmendation: There was high prevalenc. of operative deliveries, perinatal morbidity and mortality among the unbooked mothers. Girl c.ild educ.tion, employment and poverty alleviation would improve antenatal c.re utilization.

关键词： Soc.o-Demographic.c.arac.eristic. Booking Status Antenatal Delivery

Influenc. of railway wheel tread damage on wheel-rail impac. loads and the durability of wheelsets

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Railway Engineering Sc.enc. 2024年第1期32卷 20-35页

作者： Mic.ele Maglio Tore Vernersson Jens c.o.Nielsen Anders Ekberg Elena Kabo c.ARMEc Department of Mechanical and Maritime SciencesChalmers University of TechnologySE‑41296 GothenburgSweden

Dynamic.wheel-rail c.ntac. forc.s induc.d by a severe form of wheel tread damage have been measured by a wheel impac. load detec.or during full-sc.le field tests at different vehic.e *** on laser sc.nning,the measured three-dimensional damage geometry is employed in simulations of dynamic.vehic.e-trac. interac.ion to c.librate and verify a simulation *** relation between the magnitude of the impac. load and various operational parameters,suc. as vehic.e speed,lateral position of wheel-rail c.ntac.,trac. stiffness and position of impac. within a sleeper bay,is *** c.librated model is later employed in simulations featuring other forms of tread damage;their effec.s on impac. load and subsequent fatigue impac. on bearings,wheel webs and subsurfac. initiated rolling c.ntac. fatigue of the wheel tread are *** results quantify the effec.s of wheel tread defec.s and are valuable in a shift towards c.ndition-based maintenanc. of running gear,and for general assessment of the severity of different types of railway wheel tread damage.

关键词： Wheel tread damage Rolling c.ntac. fatigue c.uster Field measurements Dynamic.vehic.e-trac. interac.ion Wheel-rail impac. load Wheelset durability

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.