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large dinosaur egg accumulations and their significance for understanding nesting behaviour

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Geoscience Frontiers 2024年第5期15卷 467-488页

作者： l.Ezquerro R.Coimbra B.Bauluz C.Núñez-lahuerta T.román-Berdiel M.Moreno-Azanza departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de MadridC/JoséAntonio Novais1228040MadridSpain Aragosaurus-IUCA:Recursos Geológicos y Paleoambientales.departamento de Ciencias de la Tierra.Facultad de Ciencias Universidad de ZaragozaC/Pedro Cerbuna 1250009 ZaragozaSpain Museu da lourinha LourinhaPortugal GeoBioTec Department of Earth SciencesNOVA School of Science and TechnologyUniversidade Nova de LisboaCaparicaPortugal GeoBioTec Departamento de GeocienciasUniversidade de AveiroAveiroPortugal Insitut Catalàde Paleoecologia Humana i EvolucióSocial(IPHES-CERCA) Zona Educacional 4Campus Sescelades URV(Edifici W3)43007 TarragonaSpain departament d´Història i Història de l´Art Universitat Rovira i VirgiliAv.Catalunya 3543002 TarragonaSpain Geotransfer IUCA Departamento de Ciencias de La TierraFacultad de CienciasUniversidad de ZaragozaZaragozaSpain

The accurate identification of dinosaur egg accumulations as nests or clutches is crucial for understanding the reproductive behaviour of these extinct ***,existing methods often rely on the presence of complete eggs and embryo remains,and sedimentological criteria that are only applicable to well-structured *** this study,we introduce an innovative approach to characterize egg accumulations in structureless sediments,where traditional nest structures may not be *** methodology employs a unique combination of sedimentological,taphonomic,geochemical,and geophysical proxies for the study of egg *** applied this approach to the egg accumulation from Paimogo(Jurassic,Portugal),traditionally interpreted as a *** findings reveal that the Paimogo egg assemblage is a secondary deposit,resulting from a flooding event in a fluvial plain that dismantled several allosauroid and crocodylomorph *** eggshell vapor conductance results,coupled with sedimentological evidence,suggest that allosauroid dinosaurs buried their eggs in the dry terrain of overbank areas close to a main channel during the breeding season,likely during the dry season to prevent the embryos from *** research underscores the necessity of multidisciplinary approaches in interpreting egg accumulations and offers a novel methodology for studying these accumulations in structureless *** findings provide new insights into the breeding behaviour and nesting preferences of these extinct organisms,contributing to our understanding of dinosaur ecology.

关键词： Breeding behaviour Theropod Taphonomy Stable isotopes Magnetic susceptibility Jurassic

The Pionic deuterium and the Pion Tetrahedron Vacuum Polarization

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Journal of High Energy Physics, Gravitation and Cosmology 2024年第1期10卷 329-345页

作者： Rami rom Zikhron-Ya’akov Israel

A double-well potential model is proposed for the pionic deuterium that enables to calculate the energy split, the potential barrier height and estimate the pion tetrahedron edge length. We propose that pion tetrahedrons, πTd = ud~dũ, play a central role in the Yukawa interaction by enabling quark exchange reactions between protons and neutrons by tunneling through a potential barrier. A vacuum polarization Feynman diagram is proposed for the πTd having chains of fermion loops for the two valence quarks and anti-quarks connected by gluons. With a higher order vacuum polarization diagram, the d and u quark loops are interleaved and the chiral symmetry is broken dynamically. The proposed πTd vacuum polarization integral does not diverge in both the IR and UV limits and vanishes in the limit of an infinite pion tetrahedron condensate. We propose a new delbruck scattering Feynman diagram that includes d and u quark and anti-quark interleaved loops. We further propose that conversion of gravitons to photons may occur via quark and anti-quark loops that describe the pion tetrahedrons dynamics in the vacuum and may also transfer gravitational waves.

关键词： Pionic deuterium (πd) Yukawa Interaction QCd Vacuum double-Well Potential Chiral Perturbation Theory Vacuum Polarization Gravitational Waves

The QCd Ground State Chiral Tetrahedron Symmetry

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Journal of High Energy Physics, Gravitation and Cosmology 2023年第4期9卷 1161-1180页

作者： Rami rom Independent Researcher Zikhron-Ya’akov Israel

We propose that the exotic meson tetraquark ud~d&utilde;introduced in previous papers, may be a pseudo-Goldstone boson having a tetrahedron geometry and symmetry. The transition from the neutral pion superposition of ... 详细信息

We propose that the exotic meson tetraquark ud~dũintroduced in previous papers, may be a pseudo-Goldstone boson having a tetrahedron geometry and symmetry. The transition from the neutral pion superposition of two free mesons, dd~ and uũ, to the tetrahedron geometry with optional two chiral states may be the symmetry breaking of the QCd ground state. The ud~dũtetrahedron mass may be calculated by measuring the β decay rate variability. We assume that electrons and positrons are composite particle exotic tetraquarks, dũdd~ for the electrons and ud~dd~ for the positrons and confined by the strong force. We propose that the QCd tetrahedrons play a central role in electron pairing mechanism in both chemical bond forming and superconductor Cooper pairs. We propose a hypothesis where the QCd ground state tetrahedrons play a central role in low energy physics where quark exchange reactions between particles and the QCd tetrahedrons via gluon junctions transfer all the forces. The QCd ground state ud~dũtetrahedrons hypothesis provides a symmetry breaking and a mass gap may be created by the ground state QCd tetrahedrons Bose-Einstein condensate.

关键词： QCd Vacuum Pseudo-Goldstone Boson Bose Einstein Condensate (BEC) lattice QCd Gluon Junctions Tetrahedrons Cooper Pairs Isotope Effect Superconductor dirac Equation Klein Paradox Cosmic Web Voids doppler Redshift Black Hole laser

Cardiogenic shock due to left main related myocardial infarction:is revascularization enough?

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Journal of Geriatric Cardiology 2022年第2期19卷 152-157页

作者： Francisco Galván-román Elena Puerto Roberto Martín-Asenjo Albert Ariza-Solé department of Cardiology Bellvitge University Hospital.Grup de Malalties Cardiovasculars.Institut d´InvestigacióBiomèdica de Bellvitge(IDIBELL).L’Hospitalet de LlobregatBarcelonaSpain department of Cardiology Doce de Octubre University Hospital.Instituto de Investigación Sanitaria Hospital 12 de Octubre(imas12).MadridSpain*The authors contributed equally to this manuscript

The incidence of cardiogenic shock(CS)complicating acute myocardial infarction(AMI-CS)remains between 3%and 10%and in-hospital mortality is hardly less than 30%.[1-3]In addition,the economic cost of caring for these patients is high.[4]Revascularization in the acute phase is the only measure that has demonstrated to modify the prognosis of AMI-CS.

关键词： infarction acute mortality

discovery of gargantulides B and C,new 52-membered macrolactones from Amycolatopsis *** absolute stereochemistry of the gargantulide family

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Organic Chemistry Frontiers 2022年第2期9卷 462-470页

作者： daniel Carretero-Molina Francisco Javier Ortiz-lópez Tetiana Gren daniel Oves-Costales Jesús Martín Fernando román-Hurtado Tue Sparholt Jorgensen Mercedes de la Cruz Caridad díaz Francisca Vicente Kai Blin Fernando Reyes Tilmann Weber Olga Genilloud Fundación MEdINA Centro de Excelencia en Investigación de Medicamentos Innovadores en AndalucíaAvda.del Conocimiento 3418016 ArmillaGranadaSpain The Novo Nordisk Foundation Center for Biosustainability Technical University of DenmarkKemitorvetbuilding 2202800 Kgs.LyngbyDenmark

Gargantulides B and C,two new and highly complex 52-membered glycosylated macrolactones,were isolated from Amycolatopsis *** CA-230715 during an antibacterial screening *** structures of these giant macrolides were elucidated by 2d NMR spectroscopy and shown to be related to gargantulide A,although containing additional β-glucopyranose and/orα-arabinofuranose monosaccharides separately attached to their *** sequencing allowed the identification of a strikingly large 216 kbp biosynthetic gene cluster,among the largest type Ⅰ PKS clusters described so far,and the proposal of a previously unreported biosynthetic pathway for gargantulides *** absolute configurations of gargantulides B and C were assigned based on a combination of NMR and bioinformatics analysis of ketoreductase and enoylreductase domains within the multimodular type Ⅰ *** addition,the absolute stereochemistry of gargantulide A has now been revised and *** B and C display potent antibacterial activity against a set of drug-resistant Gram-positive bacteria and moderate activity against the clinically relevant Gram-negative pathogen Acinetobacter baumannii.

关键词： absolute membered backbone

Tailoring distinct Reactive Environments in lewis Acid Zeolites for liquid Phase Catalysis

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Accounts of Materials Research 2021年第11期2卷 1033-1046页

作者： Blake A.Johnson John R.di Iorio Yuriy román-leshkov department of Chemical Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139United States

CONSPECTUS:lewis acidic zeolites are microporous crystalline materials that offer promise as catalysts for the activation and conversion of biomassderived precursors in the liquid phase due to their unique water tolerance and synthetic *** active site environment in zeolite catalysts is multifaceted in nature and is composed of a primary catalytic binding site,the secondary pore structure that confines such binding sites,and occluded solvent and reactant molecules that interact with adsorbed ***,lewis acidic heteroatoms can adopt structurally diverse coordination that selectively catalyze different classes of chemical transformations and can be difficult to control synthetically or characterize ***,precise mechanistic interpretation of liquid-phase zeolite catalysis necessitates the development of synthetic,spectroscopic,and kinetic methods that can decouple such complex active site structures and probe the interactions that occur between confined active sites,solvent and reactant molecules,and adsorbed intermediates and transition states.

关键词： zeolite adsorbed spectroscopic

Geophysical Modeling with Satellite Gravity data: Eigen-6C4 vs. GGM Plus

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Engineering（科研） 2021年第12期13卷 690-706页

作者： Miguel Camacho román Alvarez Posgrado en Ciencias de la Tierra Universidad Nacional Autónoma de México Mexico City Mexico román Alvarez Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas (IIMAS) Universidad Nacional Autónoma de México CDMX Mexico City Mexico

Satellite data sets are an asset in global gravity collections;their characteristics vary in coverage and resolution. New collections appear often, and the user must adapt fast to their characteristics. Their use in geophysical modeling is rapidly increasing;with this in mind we compare two of the most densely populated sets: EIGEN-6C4 and GGMplus. We characterize them in terms of their frequency histograms, Free Air anomalies, power spectrum, and simple Bouguer anomalies. The nature of the digital elevation models used for data reduction is discussed. We conclude that the GGMplus data set offers a better spatial resolution. To evaluate their effect in geophysical modelling, we chose an inland region with a prominent volcanic structure in which we perform 3d inversions of the respective Bouguer anomalies, obtaining density variations that in principle can be associated with the geologic materials and the structure of the volcanic edifice. Model results are analyzed along sections of the inverted data;we conclude that the GGMplus data set offers higher resolution in the cases analyzed.

关键词： EIGEN-6C4 GGMplus Satellite Gravity data 3d inversions Nevado de Toluca

diogenes laërtius: A Moderate Skeptic in the History of Philosophy (Book IX)

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Journal of Philosophy Study 2021年第4期11卷 293-302页

作者： Ramón román-Alcalá University of Córdoba CórdobaSpain

This paper presents the keys and reasons for diogenes laërtius’ alleged scepticism, based on an analysis of thegeneral design of his work The lives and Opinions of Eminent Philosophers. I believe that it would be manifestlyerroneous to seek confirmation of this scepticism solely in Book IX without taking into account the overallstructure of the work. A convincing explanation is also provided of one of the most enigmatic and most studiedphrases in this work. What did diogenes mean when he said that Apollonides of Nicaea was ὁ παρ’ ἡμῶν (“one ofus”)?

关键词： scepticism diogenes laërtius sextus Pyrrho The lives of Philosophers

Southward Migration of Magmatic Activity in the Colima Volcanic Complex, Mexico: An Ongoing Process

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International Journal of Geosciences 2015年第9期6卷 1077-1099页

作者： román Alvarez Vsevolod Yutsis Instituto de Investigaciones en Matemáticas Aplicadas y en Sistemas Universidad Nacional Autónoma de México Ciudad Universitaria México DF México Instituto Potosino de Investigación Científica y Tecnológica San Luis Potosí México

The Colima Volcanic Complex trends in a nearly N-S direction in western Mexico, and one of its?structures, Colima volcano, is the most historically active volcano in the country. Immediately to the?N, there is another volcanic center called El Cántaro volcano, whose activity started around 1.7 Ma in its N portion and migrated to the S in various episodes. Volcanic activity migrated further south, from El Cántaro to the Colima Volcanic Complex where the southernmost manifestation, Hijos del Volcán domes, is located on the south slope of Fuego volcano. The above date appears to mark initiation of the rather continuous volcanic activity in the area. It has been noted that these volcanic manifestations lie on, or near the Rivera-Cocos inland plate boundary. Colima’s Fuego volcano is also the closest to the Middle America Trench, among the polygenetic volcanoes in Mexico. We submit that the anomalous location of volcanism in this area originates in an anomalous subduction process of the Rivera and Cocos plates and evoke a tectonic model, proposed elsewhere, to support the idea. Modeling gravimetric and aeromagnetic data we locate the magma chambers of the Fuego (active) and Nevado (extinct) volcanoes within a 65 mGals negative Bouguer anomaly elongated in a nearly N-S direction. The corresponding aeromagnetic map displays a magnetic high over the southern portion of the Fuego volcano edifice. We found two additional, associated structures whose anomalies have not been previously reported, which appear to follow the southward magmatic migration pattern. One of them is a collapse structure with a circular topographic expression, and the southernmost is a low-density intrusion ~1 km below sea level, associated with a moderate topographic bulge at the surface that we interpret as a magma body. Five lines cross the anomalies;gravimetric and magnetic fields are concurrently modeled along them to locate the magmatic bodies. In addition to the 2-d models we perform 3-d gravimetr

关键词： Colima Volcanic Complex Magma Chambers Colima Volcanoes Gravimetric Modeling Magnetic Modeling