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coupling textural and stable-isotope variations in fluvial stromatolites:comparison of Pleistocene and recent records in NE Spain

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Journal of Palaeogeography 2019年第2期8卷 150-169页

作者： c.arenas M.c.Osácar L.Auqué c.Sancho Department of Earth Sciences University of Zaragoza Geotransfer Group and Institute for Research on Environmental Sciences of Aragón(IUcA)

Textural and stable isotopic features of two middle Pleistocene fluvial stromatolite profiles are compared to a recent stromatolite,both formed in the River Piedra system(NE Spain),to test the reliability of climatic,hydrologic and depositional information derived from ancient *** Pleistocene stromatolites formed in a multi-domed,highly-inclined *** recent stromatolite also formed in a highly-inclined cascade of the River Piedra,the sedimentary conditions of which were periodically examined between the years 2000 and *** Pleistocene stromatolites are formed of an alternation of 1) thin large-crystal laminae(type A),with elongated crystals up to 1 mm long,and 2) thick small-crystal laminae(type B),consisting of cyanobacterial fan-and bushshaped *** textural and isotopic comparison with the recent stromatolite shows that each A–B couplet corresponds to one *** type-A laminae are comparable to the macrocrystalline laminae that occur in the cool-period deposits of the recent stromatolite,and the type-B laminae are comparable to the warm-period deposits of the recent *** temperatures(Tw),calculated from δ^(18)O_(calcite) and present measures of δ^(18)O_(water),were similar in the Pleistocene and recent specimens,and close to the measured river ***,the Pleistocene stromatolites formed not far from isotopic equilibrium,as did the recent *** Pleistocene δ^(18) O_(calcite) biannual oscillation is wider in amplitude than in the recent stromatolite,which suggests larger differences in Tw through the year in the Pleistocene than at *** Pleistocene δ^(13)c_(calcite) does not show any pattern;and the values are slightly higher than the recent *** co-evolution of δ^(18)O and δ^(13)c is parallel in the Pleistocene stromatolites,matching the recent stromatolite *** results and their comparison with other ancient examples prove that textural and isotopic features in ancient stromatolites

关键词： Tufa Recent and ancient stromatolites Stable isotopes Biotic and abiotic laminae Intra-annual and inter-annual water temperature variations

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Stable NiO-ceO_(2) nanoparticles with improved carbon resistance for methane dry reforming

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Journal of Rare Earths 2022年第1期40卷 57-62页

作者： Andrea cárdenas-arenas Esther Bailón-García Dolores Lozano-castelló Patrick Da costa Agustín Bueno-López Department of Inorganic chemistry University of AlicanteCarretera de San Vicente s/nE03080AlicanteSpain Sorbonne Universite Institut Jean Le Rond d'AlembertCNRS UMR 71902 place de la gare de ceinture78210Saint Cyr L'EcoleFrance

High surface area mixed oxide 8.7%NiO-ceO_(2) nanoparticles(122 m2/g;6-7 nm)were prepared using a reversed microemulsion method,and were tested for dry methane reforming(DRM).The catalytic activity of these nanoparticles remains stable under the severe conditions of DRM(700℃),and they show better carbon resistance than conventional NiO-ceO_(2) catalysts prepared without control of the *** activity and selectivity of nanoparticles and reference catalyst are similar,but nanoparticles reduce the accumulation of carbon by 63%during the DRM tests,which is a key feature for this *** and H_(2)-TPR suggest that the improved carbon resistance of the nanoparticles is due to the better interaction and cooperation between NiO and ceO_(2) mixed *** nanoparticles,the participation of cerium cations in the redox processes taking place during DRM stabilizes cationic species of *** the contrary,the catalyst prepared without control of the size suffers segregation of Ni during DRM reaction,and segregated Ni explains the higher catalytic formation of carbon.

关键词： Methane dry reforming Nickel ceria Nanoparticle Rare earths

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Tetrapartite entanglem ent features of W-c lass state in uniform acceleration

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Frontiers of physics 2020年第1期15卷 1-8页

作者： Qian Dong Ariadna J.Torres-arenas Guo-Hua Sun Shi-Hai Dong Laboratorio de Informacion cuantica CIDETECInstituto Politecnico NacionalUPALMCDMX 07700Mexico catedratica cONAcyT Centro de Investigacion en ComputacionInstituto Politecnico NacionalUPALMCDMX 07738Mexico

Using the single-mode approximatiou,we first calculate entanglement measures such as negativity(1-3 and 11 tangles)and von Neumann entropy for a tetrapartite W-class system in noninertial fiarne and then anal^e the whole entanglement measures,the residualπ4 and geometricП4 average of *** that the difference betweenπ4 andП4 is very small or disappears with the increasing accelerated *** entanglement properties are compared among the different cases from oue accelerated observer to four accelerated *** results show that there still exists entanglement for the complete system even when accelemtion r tends to *** degree of entanglement is disappeared for the 1-1 tangle case when the acceleration r>*** reexamine the Unriih effect in noninertiai *** is shown that the entanglement system in which only one qubit is accelerated is more robust than those eutangled systems in whicli two or three or four qubits are *** is also found that the von Neumann entropy S of the total system always increases with the increasing accelerated observers,but the Sκξand Sκζδwith two and three involved noniuertial qubits first increases and then decreases with the acceleration parameter r,but they are equal to constants 1 and 0.811278 respectively for zero involved iioniiiertial qubit.

关键词： tetrapartite W-class state entanglement Dirac field noninertiai frames

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Fear of cOVID-19 and emotional dysfunction problems:Intrusive,avoidance and hyperarousal stress as key mediators

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World Journal of Psychiatry 2022年第8期12卷 1088-1101页

作者： Raquel Falcó Verónica Vidal-arenas Jordi Ortet-Walker Juan c Marzo JoséA Piqueras PSIcO-REcURSOS cOVID-19 Study Group Department of Health Psychology and center for Applied Psychology Universidad Miguel HernándezElche 03202AlicanteSpain Department of Basic and clinical Psychology and Psychobiology Universitat Jaume ICastellóde la Plana 12071CastellónSpain

BAcKGROUND There is mounting empirical evidence of the detrimental effects of the coronavirus disease 2019(cOVID-19)outbreak on mental *** research has underscored the effects of similar destabilizing situations such as war,natural disasters or other pandemics on acute stress levels which have been shown to exacerbate current and future psychopathological *** To explore the role of acute stress responses(intrusive,avoidance and hyperarousal)as mediators in the association between fear of cOVID-19 and emotional dysfunction-related problems:Depression,agoraphobia,panic,obsessivecompulsive,generalized anxiety,social anxiety and health anxiety *** A sample of 439 participants from a university community in Spain(age:mean±SD:36.64±13.37;73.1%females)completed several measures assessing their fear of cOVID-19,acute stress responses and emotional dysfunction syndromes through an online *** collection was carried out from the start of home confinement in Spain until May 4,2020,coinciding with initial de-escalation *** of the dataset included descriptive and frequency analyses,Mann-Whitney U Test of intergroup comparisons and path analysis for direct and indirect *** is an observational,descriptive-correlational and crosssectional *** The prevalence of clinical symptoms in our sample,reported since the beginning of the pandemic,reached 31.44%.The female group presented higher scores although the effect size was ***,the participants who exceeded the clinical cut-off points in emotional problems showed higher levels of fear of cOVID-19 and of cognitive,motor and psychophysiological responses of acute stress,unlike the group with normative *** addition,the results show significant mediated effects of hyperarousal stress among fear of cOVID-19 and emotional dysfunction ***,the clinical syndromes most related to the consequences of the pandemic(e.g.,social contact avoi

关键词： Fear of cOVID-19 Acute stress Emotional dysfunction Psychophysiological activation Mediated effects

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Entanglement measures of a new type pseudo-pure state in accelerated frames

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Frontiers of physics 2019年第2期14卷 23-29页

作者： Qian Dong Ariadna J. Torres-arenas Guo-Hua Sun Wen-chao Qiang Shi-Hai Dong Laboratorio de Informacion cuantica CIDETECInstituto Polit .crrico NacionalUPALMCD MX 07700Mexico catedratica cONAcyT Centro de Investigacion en ComputacionInstituto Politecnico NacionalUPALMMexico D. F. 07700Mexico Faculty of Science Xi'an University of Architecture and TechnologyXi'an 710055China

In this work we analyze the characteristics of quantum entangleinent of the Dirac field in noninertial reference frames in the context of a new type pseudo-pure state, which is composed of the Bell states. This will help us to understand the relationship between the relativity and quantum information theory. Some states will be changed from entangled states into separable ones around the critical value F = 1/4, but there is no such a critical value for the variable y related to acceleration a. We find that the negativity Nas (ρ^TA AB 1) increases with F but decreases with the variable y、while the variation of the negativity Nb1b11(ρ^TB1 B1B11)is opposite to that of the negativity N AB1(ρ^TA AB1). We also study the von Neumann entropies S(ρAB1) and S(ρB1B11)、We find that the S(ρAB1) increases with variable y but S(ρB1B11) is independent of it. However, both S(ρAB1) and S(ρB1B11) first decreases with F and then increases with it. The concurrences c(ρAB1) and c(ρB1B11) are also discussed. We find that the former decreases with y while the latter increases with y but both of them first increase with F and then decrease with it.

关键词： negativity pseudo-pure state noninertial frame entanglement von Neumann entropy concurrence

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Hydrothermal synthesis of pyrrhotite(Fex-1S) nanoplates and their antibacterial, cytotoxic activity study

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Progress in Natural Science:Materials International 2018年第4期28卷 447-455页

作者： Liliana Argueta-Figueroa Nayely Torres-Gómez René García-contreras A.R.Vilchis-Nestor O.Martínez-Alvarez L.S.Acosta-Torres M.c.arenas-Arrocena Laboratorio de Investigación Interdisciplinaria área de Nanoestructuras y Biomateriales Escuela Nacional de Estudios Superiores Unidad León Universidad Nacional Autónoma de México centro conjunto de Investigación en Química Sustentable (ccIQS) UEAMex-UNAM Departamento de Ingeniería en Energía Universidad Politécnica de Guanajuato

The aim of this study was to synthesize and characterize Fex-1S 2D-nanostructures with pyrrhotite phase,as well as to explore their biological(antibacterial and cytotoxic)properties,namely the expression of reactive oxygen species(ROS)in the exposure of cells and *** on hydrothermal synthesis,the characterization of asprepared 2D-nanostructures was performed by XRD,SEM,EDS,and TEM,in which the single-crystalline pyrrhotite phased Fex-1S nanoplate morphology was *** antibacterial activities of Fex-1S nanoplates against human pathogenic strains such as Staphylococcus aureus,Escherichia coli,and Enterococcus faecalis were *** inhibitory concentration(MIc)and minimum bactericidal concentration(MBc)were determined following the broth microdilution *** and expression of intracellular ROS of pyrrhotite nanoplates on Human Gingival Fibroblast(HGF),Human Pulp cells(HPc)and Human Osteoblast(HBc)were *** viability was determined by the MTT *** experiments were performed of three independent experiments and data were analyzed by Kruskal-Wallis and Mann-Whitney tests,also Pearson′s correlation was *** nanoplates exhibited good bactericidal *** types of cells tested showed slight *** was found that intracellular ROS is produced when cells and bacteria tested are exposed to pyrrhotite nanoplates in presence of both air and peroxide *** production levels were higher in the bacteria than the cells exposed to these nanoplates.

关键词： Hydrothermal synthesis Iron sulfide nanoplates Minimal inhibitory concentration Antibacterial effect cytotoxicity assay

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Frontier of the Paleo-Tethys Ocean in the western Mediterranean:Isotopic(Sm-Nd)constraints on sources of Devonian units from Menorca Island

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Geoscience Frontiers 2024年第5期15卷 323-338页

作者： Ricardo arenas Jose M.Fuenlabrada cristian Timoner Rubén Díez Fernández Esther Rojo-Pérez Departamento de Mineralogía y Petrología and Instituto de Geociencias(UcM CSIC)Universidad ComplutenseMadridSpain Unidad de Geocronología(cAI de ciencias de la Tierra y Arqueometría) Universidad ComplutenseMadridSpain Bayerisches Geoinstitut University of BayreuthBayreuthGermany Instituto Geológico y Minero de España–cSIc SalamancaSpain

The c.1000-m-thick pre-orogenic Devonian mainly metapelitic sequence of North Menorca Island shows a fairly complete stratigraphic *** rocks of this sequence indicate gradually increasing deeper marine conditions of sedimentation towards its uppermost ***,the obtained sedimentary characteristics resemble those related to a deep and narrow basin-associated *** sills of Ti-augite-bearing alkaline gabbros occur within the Devonian *** intensity of Variscan deformation increases downwards through the *** to the characteristics of the Devonian sequence and its location within the Variscan Orogen,a correlation with similar units located in the southern sectors of the central Iberian Zone(Iberian Massif)is *** Devonian metapelitic rocks have geochemical characteristics suggesting that they represent moderately recycled mature siliciclastic sediments,generated from erosion of distant source areas belonging to an upper continental *** relatively narrow range of variation observed in initial^(143)Nd/^(144)Nd ratios supports a similar source for the Menorcan slates(0.51165–0.51182).However,a marked trend is observed in these isotope ratios,from lower values at the base of the stratigraphic column(minimum value of 0.511941)to higher values at the top(maximum value of 0.512131).The^(147)Sm/^(144)Nd ratios vary between 0.1074 and 0.1238,within the range defined for siliciclastic rocks with felsic crustal *** Nd model ages define a narrow range between 1496 Ma and 1754 Ma(Late Paleoproterozoic–Early Mesoproterozoic),and they are consistently younger *** data rule out a provenance from the erosion of the West Africa craton,as they are more compatible with a provenance from regions located in the Trans-Saharan Belt or Sahara *** characteristics of the Menorcan Devonian sequence are compatible with its deposition in a narrow and deep peri-Gondwanan transtensional basin,gener

关键词： Western Paleo-Tethys frontiers Menorca Island Sm-Nd isotopic constraints Devonian sequence provenance in Gondwana

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Efficacy and safety of deep sclerectomy with uveoscleral implant plus collagen matrix implant overcoming the superficial scleral flap in glaucoma surgery

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International Journal of Ophthalmology(English edition) 2023年第11期16卷 1806-1813页

作者： Jéssica Botella-García Marta Balboa Pau Romera-Romero Theo Stijnen Adrián Sánchez-Fortún Karl Mercieca Jordi Loscos-arenas Department of Ophthalmology Hospital Germans Trias i PujolBadalona 08916Spain International University of catalonia(UIc) Barcelona 08017Spain Department of Surgery Barcelona Autonomous University(UAB)Barcelona 08035Spain Department of Biomedical Data Sciences Leiden University Medical CenterLeiden 2333The Netherlands University Hospitals Bonn Eye clinic Bonn53127Germany Germans Trias i Pujol Research Institute(IGTP) Badalona 08916Spain

AIM:To assess the efficacy and safety of non-penetrating deep sclerectomy(NPDS)with uveoscleral implant plus subconjunctival and intrascleral collagen matrix overcoming the superficial scleral flap lips(modified deep sclerectomy technique,DS)and minimal use of mitomycin c in glaucoma ***:A retrospective review of 47 consecutive glaucoma patients who underwent NPDS with DS between January 2017 and May ***-corrected visual acuity,intraocular pressure(IOP),post-operative need for glaucoma medications,visual field mean deviation(MD),re-interventions,needling revisions and laser goniopuncture were *** success was defined as IOP≤18 mm Hg without topical *** success was defined as the same criteria but with the addition of any antihypertensive *** over 18 mm Hg on two consecutive followup visits was considered as a ***:Fifty-two eyes of 47 patients were *** preoperative IOP was 25.37±6.47 mm Hg,and decreased to 15.04±4.73 at 12mo and 12.21±4.1 at 24mo(all Pcal medications dropped from a mean of 3.06±0.25 per patient to 0.51±0.99 and 1.11±1.23 respectively after 12 and 24mo(all Pcations were required in 45.5%of patients after *** and absolute success rate at 24mo were 85.5%±5%and 48.5%±7.4%,***:DS is a safe and effective nonpenetrating glaucoma surgery *** aims to retain the patency of all pathways created for aqueous humor drainage:the intrascleral bleb,the supraciliary space and the open communication between intrascleral and subconjunctival compartments.

关键词： deep sclerectomy glaucoma surgery uveoscleral implant

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Activation and IL-1B secretion of human peripheral phagocytes infected with Actinomadura madurae,Nocardia asteroides and candida albicans

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Asian Pacific Journal of Tropical Medicine 2016年第10期9卷 939-944页

作者： Alejandro Palma-Ramos Gilberto casillas-Petriz Laura Estela castrillon-Rivera Jorge Ismael castaneda-Sanchez Roberto arenas-Guzman Maria Elisa Drago-Serrano Teresita Sainz-Espunes Department of Biological Systems Autonomous Metropolitan University Campus XochimilcoCalzada del Hueso No.1100Ciudad de Mexico 04960Mexico Service of Dermatology and Mycology General Hospital ‘Manuel Gea Gonzalez’Calzada de Tlalpan 4800TlalpanSeceion XVI14080 Ciudad de MexicoMexico

Objective: To evaluate the ability of Actinomadura madurae(A. madurae) and Nocardia asteroids(N. asteroides), using candida albicans(c. albicans) as prototypic control, to elicit the activation and IL-1β secretion of blood phagocytic cells from healthy donors. Methods: Microcopic evaluation of phagocytosis/activation, cell viability and spectrophotometric quantitation of endocytosis/activation, were assessed by using formazan blue test in human blood phagocytes infected with c. albicans, A. madurae or N. asteroides treated with either normal human serum(NHS) or with decomplemented NHS. Interlukin-1β from culture supernatants of infected polymorphonuclear was tested by ELISA kit assay. Results: Microscopic assay showed that phagocytosis and activation of adherent mononuclear phagocytes were greater with c. albicans followed by A. madurae and then by N. asteroides. Spectrophotometric assay in polymornuclear phagocytes infected with NHS-treated pathogens indicated that activation was similarly higher by c. albicans and A. madurae and lower by N. asteroides. Kinetic assays in infected polymorphonuclear cells showed that viability was decreased by c. albicans and N. asteroides or unaffected with A. madurae. Levels of IL-1β at 8 h of incubation were higher with c. albicans followed by A. madurae whereas lower levels were found with N. asteroides. conclusions: The extent of cell-viability and activation as well IL-1β secretion may be related with the virulence of c. albicans and N. asteroides and other parameters remain to be explored for assesing the virulence of A. madurae.

关键词： Interleukin-1B Phagocytosis Actinomycetoma Formazan blue assay

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Minimizing sperm oxidative stress using nanotechnology for breeding programs in rams

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2395-2410页

作者： Alejandro Jurado‑campos Pedro Javier Soria‑Meneses Maria arenas‑Moreira carlos Alonso‑Moreno Virginia Rodriguez‑Robledo Ana Josefa Soler Jose Julian Garde Maria del Rocio Fernandez‑Santos SaBio IREc(cSIc-UcLM-JccM) Campus UniversitarioS/N02071 AlbaceteSpain. Departamento de Quimica Inorganica Organica Y Bioquimica‑Centro de Innovacion en Quimica Avanzada(ORFEO‑CINQA)Facultad de FarmaciaUniversidad de Castilla-La Mancha02008 AlbaceteSpain. centro Regional de Investigacion Biomedicas Unidad nanoDrugUniversidad de Castilla-La Mancha02008 AlbaceteSpain. Facultad de Farmacia Universidad de Castilla La Mancha02071 AlbaceteSpain.

Background Artificial insemination(AI)is a routine breeding technology in animal ***,the temperature-sensitive nature and short fertile lifespan of ram sperm samples hamper its use in *** this sense,nanotechnology is an interesting tool to improve sperm protection due to the development of nanomaterials for AI,which could be used as delivery *** this work,we explored the feasibility of vitamin E nanoemulsion(NE)for improving sperm quality during *** With the aim of evaluating this proposal,ejaculates of 7 mature rams of Manchega breed were collected by artificial vagina and extended to 60×10^(6)spz/mL in *** containing control and NE(12 mmol/L)with and without exogenous oxidative stress(100μmol/L Fe2+/ascorbate)were stored at 22 and 15℃and motility(cASA),viability(YO-PRO/PI),acrosomal integrity(PNA-FITc/PI),mitochondrial membrane potential(Mitotracker Deep Red 633),lipoperoxidation(c11 BODIPY 581/591),intracellular reactive oxygen species(ROS)production and DNA status(ScSAR)monitored during 96 *** results show that NE could be used to maintain ram spermatozoa during transport at 15 and 22℃for up to 96 h,with no appreciable loss of kinematic and physiological characteristics of freshly collected *** The storage of ram spermatozoa in liquid form for 2-5 d with vitamin E nanoemulsions may lead more flexibility to breeders in AI *** view of the potential and high versatility of these nanodevices,further studies are being carried out to assess the proposed sperm preservation medium on fertility after artificial insemination.

关键词： Breeding technology Nanoemulsions Nanotechnology Sperm oxidative stress Vitamin E

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