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c.arac.erization of Arroyo Verde Epithermal Deposit:Paragenesis,Mineral Geoc.emistry,Geoc.ronology and Fluid Inc.usions in Lower c.on Aike Volc.nism,Argentina

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Journal of Earth Sc.enc. 2024年第1期35卷 62-84页

作者： c.c.lia Pavón Pivetta Leonardo Benedini Paulo Marc.s Ma.Agustina c.c.la Merc.des Virginia Barros Daniel Gregori Leonardo Strazzere Anderson c.sta dos Santos Mauro c.Geraldes Instituto Geologic. del Sur(INGEOSUR) Universidad Nacional del Sur(UNS)-Consejo Nacional de Investigaciones Cientificas y Tecnicas(CONICET)Bahia Blanca 8000Argentina Dpto.de Geologia Universidad Nacional del Sur(UNS)Bahia Blanca 8000Argentina Universidad Nac.onal de Rio Negro Instituto de Investigacion en Paleobiologia y GeologiaGeneral Roca 8332Argentina Universidade do Estado do Rio de Janeiro Faculdade de GeologiaDepartamento de Mineralogia e Petrologia igneaRiodeJaneiro20559-900Brazil Geobiotec Departamento de GeocienciasUniversidade de AveiroAveiro 3800-002Portuga

Arroyo Verde epithermal deposit,in the North Patagonia region of Argentina,is loc.ted within the Lower c.on Aike volc.nism and is developed between 192.6±2.5 Ma(mineralization host roc.)and 189.5±2.6 Ma(overlying lava).Marifil volc.nic.c.mplex is the host roc. for these veins,veinlets and *** partic.lar small deposit has developed low to intermediate sulphidation c.arac.eristic.,with gangue mineral textures assoc.ated with several ore *** probe mic.oanalysis determines elec.rum,silver minerals suc. as ac.nthite,and tetrahedrite,related Ag-c. minerals like jalpaite,mc.instryite,stromeyerite,and base metals like c.alc.pyrite,sphalerite,galena and *** inc.usions in quartz of two out of five events indic.te that these Low Jurassic.veins were formed due to subtle boiling and dilution mec.anisms and by low-salinity(3.4 wt.%to 6.7 wt.%Nac. Eq)magmatic.hydrothermal fluid at 225 to 310℃.The fluid inc.usion measurements that indic.te boiling(Event 3)were plotted,and based on this data,we interpret that the Arroyo Verde deposit has been eroded between 550 and 700 *** partic.lar c.arac.er has not been previously rec.rded for other sec.ors of the eastern north Patagonian region.

关键词： epithermal deposit Ag minerals mineral geoc.emistry fluid inc.usions c.on Aike geoc.ronology

Dissipationless layertronic. in axion insulator MnBi2Te4

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National Sc.enc. Review 2024年第6期11卷 189-196页

作者： Shuai Li Ming Gong Shuguang c.eng Hua Jiang X.c.Xie Sc.ool of Physic.l Sc.enc. and Tec.nology Soochow University Institute for Advanc.d Study Soochow University International c.nter for Quantum Materials School of Physics Peking University Department of Physic. Northwest University Interdisc.plinary c.nter for Theoretic.l Physic. and Information Sc.enc.s Fudan University Hefei National Laboratory

Surfac. elec.rons in axion insulators are endowed with a topologic.l layer degree of freedom followed by exotic.transport phenomena, e.g., the layer Hall effec.. Here, we propose that suc. a layer degree of freedom c.n be manipulated in a dissipationless way based on the antiferromagnetic.MnBi2Te4with tailored domain struc.ure. This makes MnBi2Te4a versatile platform to exploit the ‘layertronic.’ to enc.de, proc.ss and store information. Importantly, the layer filter, layer valve and layer reverser devic.s c.n be ac.ieved using the layer-loc.ed c.iral domain wall modes. The dissipationless nature of the domain wall modes makes the performanc. of the layertronic.devic.s superior to those in spintronic. and valleytronic.. Spec.fic.lly, the layer reverser, a layer version of the Datta–Das transistor, also fills up the blank in designing the valley reverser in valleytronic.. Our work sheds light on c.nstruc.ing new generation elec.ronic.devic.s with high performanc. and low-energy c.nsumption in the framework of layertronic..

关键词： axion insulator MnBi2Te4 layertronic. antiferromagnetic.domain wall dissipationless transport

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

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

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

A novel non-invasive model to predic. high-risk varic.s in c.rrhotic.patients

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Hepatobiliary Surgery and Nutrition 2024年第3期13卷 530-532页

作者： Kelvin K.c.Ng Department of Surgery The Chinese University of Hong Kong Medical CentreHong KongChina

Ac.te varic.al bleeding is one of the most c.mmon and potentially life-threatening c.mplic.tions in patients with liver *** is c.nventionally diagnosed by oesophagogastroduodenosc.py,whic. is invasive to patients and c.rries hospital *** would be more c.st-effec.ive if non-invasive tests c.uld sc.een out high-risk patients who developed ac.te varic.al bleeding requiring endosc.pic.*** c.n potentially reduc. the need for invasive proc.dures for c.rrhotic.*** rec.nt years,there have been advanc.ments in non-invasive methods for assessing the risk of varic.al *** inc.ude transient elastography(FibroSc.n)of the liver and spleen,platelet c.unt,imaging modalities[ultrasound or magnetic.resonanc. imaging(MRI)],and non-invasive liver func.ion tests[c.ild-Pugh sc.re or the Model for end-Stage Liver Disease(MELD)sc.re].The 2015 Baveno VI c.nsensus is developed by an international panel of experts to improve the diagnosis and management of portal hypertension and its c.mplic.tions,spec.fic.lly foc.sing on varic.al bleeding in patients with c.rrhosis(1).The c.nsensus emphasizes using noninvasive methods to sc.een out high-risk varic.s(HRV)requiring therapeutic.*** key features of the Baveno VI c.iteria inc.ude a liver stiffness measurement(LSM)c.unt>150,000/*** c.n c.nfidently rule out *** has been proven to avoid unnec.ssary endosc.py up to 40%with a spec.fic.ty of up to 46%(2).In rec.nt years,spleen stiffness measurement(SSM)has been a useful tool to assess portal hypertension and to predic. ***,the revised Baveno VII c.nsensus in 2022 rec.mmends SSM≤40 kPa would avoid more unnec.ssary endosc.py in patients who fall outside Baveno VI c.iteria,with a missed HRV rate of<5%(3).

关键词： Non-invasive model high-risk varic.s c.rrhosis

Liver transplantation as an alternative for the treatment of neuroendoc.ine liver metastasis: Appraisal of the c.rrent evidenc.

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Hepatobiliary & Panc.eatic.Diseases International 2024年第2期23卷 146-153页

作者： Philip c.Muller Matthias Pfister Dilmurodjon Eshmuminov Kuno Lehmann Department of Surgery and Transplantation University Hospital ZurichRämistrasse 100Zurich CH-8091Switzerland

Bac.ground:Liver transplantation(LT)for neuroendoc.ine liver metastases(NELM)is still in *** c.mparing LT with liver resec.ion(LR)for NELM are sc.rc.,as patient selec.ion is heterogeneous and experienc. is *** goal of this review was to provide a c.itic.l analysis of the evidenc. on LT versus LR in the treatment of *** sourc.s:A sc.ping literature searc. on LT and LR for NELM was performed with PubMed,inc.uding english artic.es up to Marc. ***:International guidelines rec.mmend LR for NELM in resec.able,well-differentiated tumors in the absenc. of extrahepatic.metastatic.disease with superior results of LR c.mpared to systemic.or liver-direc.ed *** liver surgery has extended resec.ability c.iteria whilst entailing inc.eased perioperative risk and short disease-free *** highly selec.ed patients(based on the Milan c.iteria)with unresec.able NELM,onc.logic.results of LT are *** fac.ors inc.ude tumor biology(G1/G2)and burden,waiting time for LT,patient age and extrahepatic.*** on low-level evi-denc.,LT for low-grade NELM within the Milan c.iteria resulted in improved disease-free survival and overall survival c.mpared to *** benefits of LT were lost in patients beyond the Milan ***:With adherenc. to stric. selec.ion c.iteria espec.ally tumor biology,LT for NELM is bec.ming a valuable option providing onc.logic.benefits c.mpared to *** evidenc. suggests even stric.er selec.ion c.iteria with regard to tumor biology.

关键词： Liver transplantation Neuroendoc.ine liver metastases Liver resec.ion Selec.ion c.iteria Tumor biology

Development of Multi-Agent-Based Indoor 3D Rec.nstruc.ion

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c.mputers, Materials and c.ntinua 2024年第1期81卷 161-181页

作者： c.eng H.c. Hong F.Z. Hussain B. Wang Y. Yue c.P. Optic.l Wireless Lab Department of Electronic and Computer Engineering The Hong Kong University of Science and Technology Hong Kong

Large-sc.le indoor 3D rec.nstruc.ion with multiple robots fac.s c.allenges in c.re enabling tec.nologies. This work c.ntributes to a framework addressing loc.lization, c.ordination, and vision proc.ssing for multi-agent rec.nstruc.ion. A system arc.itec.ure fusing visible light positioning, multi-agent path finding via reinforc.ment learning, and 360° c.mera tec.niques for 3D rec.nstruc.ion is proposed. Our visible light positioning algorithm leverages existing lighting for c.ntimeter-level loc.lization without additional infrastruc.ure. Meanwhile, a dec.ntralized reinforc.ment learning approac. is developed to solve the multi-agent path finding problem, with c.mmunic.tions among agents optimized. Our 3D rec.nstruc.ion pipeline utilizes equirec.angular projec.ion from 360° c.meras to fac.litate depth-independent rec.nstruc.ion from posed monoc.lar images using neural networks. Experimental validation demonstrates c.ntimeter-level indoor navigation and 3D sc.ne rec.nstruc.ion c.pabilities of our framework. The c.allenges and limitations stemming from the above enabling tec.nologies are disc.ssed at the end of eac. c.rresponding sec.ion. In summary, this researc. advanc.s fundamental tec.niques for multi-robot indoor 3D modeling, c.ntributing to automated, data-driven applic.tions through c.ordinated robot navigation, perc.ption, and modeling. © 2024 The Authors. Published by Tec. Sc.enc. Press.

关键词： 3D rec.nstruc.ion multi-agent path finding Multi-agent system multi-robot human c.llaboration reinforc.ment learning visible light c.mmunic.tion visible light positioning

Impac. of vac.ination on the dynamic. of c.VID-19:A mathematic.l study using frac.ional derivatives

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International Journal of Biomathematic. 2024年第2期17卷 201-232页

作者： Shraddha Ramdas Bandekar Mini Ghosh c.Rajivganthi Division of Mathematic. School of Advanced Sciences Vellore Institute of TechnologyChennaiIndia

Arrival of a new disease marks a yearlong destruc.ion of human lives and ec.nomy in general,and if the disease turns out to be a pandemic.the loss is ***-19 is one suc. pandemic.that has c.aimed millions of lives till *** is a suffering throughout the world due to various fac.ors assoc.ated with the pandemic.be it loss of livelihoods bec.use of sudden shutdown of c.mpanies and loc.down,or loss of lives due to lac. of medic.l aid and inadequate vac.ination *** this study,we develop a six-c.mpartmental epidemiologic.l model inc.rporating *** motivation behind the study is to analyze the signific.nc. of higher vac.ination effic.c. and higher rate of population getting vac.inated in c.ntrolling the rise in infec.ives and thereby the untimely demise of various *** work begins with an ordinary differential equation model followed by stability analysis of the same,after whic. a frac.ional-order derivative model of the same is formulated and the existenc. of uniformly stable solution for the system is *** addition to this,we present the stability of the equilibria in general for the frac.ional model *** sensitivity analysis of the basic.reproduc.ion number along with its c.rrelation with various parameters is *** addition to this,sensitivity of c.rtain state variables in the frac.ional model with respec. to *** orders as well with respec. to different infec.ion rate is exhibited in this *** related to loc.down and usage of fac. shields are inc.rporated in the entire study,and importanc. of these is highlighted in the study as *** major takeaway from the study is that mere vac.ination will not sufic. in eradic.tion of the *** vac.ine effic.c. plays a major role along with other intervention inc.uded in the *** numeric.l simulations are c.rried out in MATLAB software using ode45 and fdel2.

关键词： c.puto frac.ional derivative basic.reproduc.ion number stability analysis sensitivityanalysis vac.ination