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Influence of metal support in-plane symmetry on the corrugation of hexagonal boron nitride and graphene monolayers

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Nano Research 2018年第9期11卷 4643-4653页

作者： Antonio d. martinez-Galera Jose m. gomez-Rodriguez Departamento de Fisica de la matefia Condensada Universidad Autonoma de Madrid Madrid E-28049 Spain Condensed matter Physics Center (IFImAC) UniversidadAutdnoma de Madrid Madrid E-28049 Spain Instituto Nicolds cabrera Universidad Autonoma de Madrid Madrid E-28049 Spain

Predicting the properties of two-dimensional （2D） materials as graphene and hexagonal boron nitride （h-BN） monolayers after their growth on any given substrate is a major challenge. While the influence of the electron configuration of the atoms of the underlying surface is well-understood, the effect of substrate geometry still remains unclear. The structural properties of h-BN monolayers grown on a rectangularly packed Rh（110） surface were characterized in situ by ultrahigh vacuum scanning tunneling microscopy and were compared to those that this material exhibits when grown on substrates showing different crystallographic orientations. Although the h-BN monolayer grown on Rh（110） was dominated by a unique quasiunidimensional moir6 pattern, suggesting considerable interface interaction, the moir6 corrugation was unexpectedly smaller than those reported for strongly interacting interfaces with hexagonal-terminated substrates, owing to differences in the possible binding landscapes at interfaces with differently oriented substrates. moreover, a rule was derived for predicting how interface corrugation and the existence and extent of subregions within moir6 supercells containing favorable sites for orbital mixing between h-BN monolayers and their supports depend on substrate symmetry. These general symmetry considerations can be applied to numerous 2D materials, including graphene, thereby enabling the prediction of how substrate choice determines the properties of these materials. Furthermore, they could also provide new routes for tuning 2D material properties and for developing nanotemplates showing different geometries for Krowing adsorbate superlattices.

关键词： hexagonal boron nitride graphene two-dimensional materials scanning tunneling microscopy moire superstructures nanotemplates

On SIR epidemic models with generally distributed infectious periods： Number of secondary cases and probability of infection

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International Journal of Biomathematics 2017年第2期10卷 157-169页

作者： A. gomez-Corral m. Lopez-Garcia Instituto de Ciencias matemdticas CSIC- UAM- UC3M- UCM Calle Nicolds Cabrera 13-15 Madrid 28049 Spain Department of Applied mathematics School of Mathematics University of Leeds Leeds LS29JT UK

Recently, Clancy [SIR epidemic models with general infectious period distribution, Statist. Prob. Left. 85 （2014） 1-5] has shown how SIR epidemics in which individuals＇ infection periods are not necessarily exponentially distributed may be modeled in terms of a piecewise-deterministic markov process （PDmP）. In this paper, we present a more detailed description of the underlying PDmP, from which we analyze the population transmission number and the infection probability of a certain susceptible individual.

关键词： Number of secondary cases piecewise-deterministic markov process proba-bility of infection SIR epidemic model.

Instability and sensitivity analysis of flows using OpenFOAm~

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Chinese Journal of Aeronautics 2016年第2期29卷 316-325页

作者： Liu Qiong F. gomez J.m. Perez V. Theofilis School of Aeronautics Universidad PolitOcnica de Madrid Plaza Cardinal Cisneros 3 Madrid E-28040 Spain Department of mechanical and Aerospace Engineering Monash University Victoria 3800 Australia

The present contributions deal with the development and implementation of the direct and adjoint incompressible Navie-Stokes equations in a matrix-free time-stepping context making use of the open-source OpenFOAm~ （open source field operation and manipulation） C ＋＋ tool- box. It is shown that a few minor modifications in the source code can enable these multi-purpose computational fluid dynamics （CFD） solvers to carry out global instability analysis of three- dimensional flows of engineering interest, exploiting all additional capabilities of such codes. The strength of this methodology is demonstrated through the analysis of an interesting selection of ooen and wall-bounded flows.

关键词： Adjoint-based analysis Computational fluid dynam-ics Flow instability OpenFOAm Time-stepping method

The effect of rippling on the mechanical properties of graphene

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Nano materials Science 2022年第1期4卷 18-26页

作者： Guillermo Lopez-Polin Cristina gomez-Navarro Julio gomez-Herrero Instituto de Ciencia de materiales de madrid CSICMadrid E 28049Spain Departamento de Física de La materia Condensada Universidad Autónoma de MadridMadridE-28049Spain IFImAC Condensed matter Physics Center(IFImAC).Universidad Autónoma de madrid MadridE-28049Spain

Graphene is the stiffest material known so far but, due to its one-atom thickness, it is also very ***, free-standing graphene exhibit ripples that has major effects on its elastic properties. Here we will summarize three experiments where the influence of rippling is essential to address the results. Firstly, we observed that atomic vacancies lessen the negative thermal expansion coefficient(TEC) of free-standing *** also observed an increase of the Young's modulus with global applied strain and with the introduction of small density defects that we attributed to the decrease of rippling. Here, we will focus on a surprising feature observed in the data: the experiments consistently indicate that only the rippling with wavelengths between 5 and 10 nm influences the mechanics of graphene. The rippling responsible of the negative TEC and anomalous elasticity is thought to be dynamic, i.e. flexural phonons. However, flexural phonons with these wavelengths should have minor effects on the mechanics of graphene, therefore other mechanisms must be considered to address our observations. We propose static ripples as one of the key elements to correctly understand the thermomechanics of graphene and suggest that rippling arises naturally due to a competition of symmetry breaking and anharmonic fluctuations.

关键词： Graphene mechanical properties Atomic force microscopy Defects Ripples Stmain

Haplotype phasing after joint estimation of recombination and linkage disequilibrium in breeding populations

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Journal of Animal Science and Biotechnology 2014年第1期5卷 38-52页

作者： Luis gomez-Raya Amanda m Hulse David Thain Wendy m Rauw Departamento de mejora Genética Animal Instituto Nacional deInvestigación y Tecnología Agraria y Alimentaria (INIA) Interdisciplinary Program in Genetics Texas A&M University College Station Department of Animal Biotechnology University of Nevada

A novel method for haplotype phasing in families after joint estimation of recombination fraction and linkage disequilibrium is developed. Results from monte carlo computer simulations show that the newly developed E.m. algorithm is accurate if true recombination fraction is 0 even for single families of relatively small sizes. Estimates of recombination fraction and linkage disequilibrium were 0.00 （SD 0.00） and 0.19 （SD 0.03） for simulated recombination fraction and linkage disequilibrium of 0.00 and 0.20, respectively. A genome fragmentation phasing strategy was developed and used for phasing haplotypes in a sire and 36 progeny using the 50 k Illumina BeadChip by： a） estimation of the recombination fraction and LD in consecutive SNPs using family information, b） linkage analyses between fragments, c） phasing of haplotypes in parents and progeny and in following generations. Homozygous SNPs in progeny allowed determination of paternal fragment inheritance, and deduction of SNP sequence information of haplotypes from dams. The strategy also allowed detection of genotyping errors. A total of 613 recombination events were detected after linkage analysis was carried out between fragments. Hot and cold spots were identified at the individual （sire level）. SNPs for which the sire and calf were heterozygotes became informative （over 90%） after the phasing of haplotypes. Average of regions of identity between half-sibs when comparing its maternal inherited haplotypes （with at least 20 SNP） in common was 0.11 with a maximum of 0.29 and a minimum of 0.05. A monte-carlo simulation of BTA1 with the same linkage disequilibrium structure and genetic linkage as the cattle family yielded a 99.98 and 99.94% of correct phases for informative SNPs in sire and calves, respectively.

关键词： Breeding Haplotype phasing Linkage disequilibrium SNP

Inference for a truncated positive normal distribution

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Applied mathematics(A Journal of Chinese Universities) 2018年第2期33卷 163-176页

作者： Hector J.gomez Neveka m.Olmos Hector Varela Heleno Bolfarine Departamento de Ciencias matematicas y Ffsicas Facultad de IngenierlaUniversidad Catolica de TemucoTemucoChile Departamento de matematicas Facultad de Ciencias BasicasUniversidad de AntofagastaAntofagastaChile Departamento de Estatfstica IMEUniversidade de Sao PauloSao PauloBrazil

The main object of this paper is to study an extension of the half normal distribution defined by adding a positive truncation to it. The new model is more flexible than the half-normal distribution and contains the half normal distribution as a special case. Properties of this distribution, such as moments, hazard function and entropy are studied and parameters estimation is dealt with by using inoinents and inaxiinuin likelihood. A real data application indicates good fit performance of the new model when compared to other competitors in litera- tures.

关键词： half-normal distribution maximum likelihood truncation

A New Perspective of the Physical Processes Associated with the Clear-Sky Greenhouse Effect over High Latitudes

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Advances in Atmospheric Sciences 2004年第2期21卷 171-180页

作者： Zuohao ca0 Ronald E．STEWART m．K．YAU meteorologicalServiceofcanada，Ontario，canada DepartmentofAtmosphericandOceanicSciences，mcGillUniversitymontreal，Quebec，canada

The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations far the subarctic winter and summer standard atmosphere using the radiation model mODTRAN3 (moderate Resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.

关键词： greenhouse effect surface ernissivity physical processe high latitude seasonal variation

Integrating geographical information in the Linked Digital Earth

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International Journal of Digital Earth 2014年第7期7卷 554-575页

作者： Luis m.Vilches-Blazquez Boris Villazon-Terrazas Oscar Corcho Asuncion gomez-Perez Ontology Engineering Group Departamento de Inteligencia ArtificialFacultad de InformaticaUniversidad Politecnica de MadridMadridSpain

many progresses have been made since the Digital Earth notion was envisioned thirteen years ***,the mechanism for integrating geographic informa-tion into the Digital Earth is still quite *** this context,we have developed a process to generate,integrate and publish geospatial Linked Data from several Spanish National *** data-sets are related to four Infrastructure for Spatial Information in the European Community(INSPIRE)themes,specifically with Administrative units,Hydrography,Statistical units,and *** main goal is to combine different sources(heterogeneous,multidisciplinary,multitemporal,multiresolution,and multilingual)using Linked Data *** goal allows the overcoming of current problems of information integration and driving geographical information toward the next decade scenario,that is,‘Linked Digital Earth’.

关键词： geographical information integration Digital Earth Linked Data

Game changer:How Janus kinase inhibitors are reshaping the landscape of ulcerative colitis mana

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World Journal of Gastroenterology 2024年第35期30卷 3942-3953页

作者： Antonio m caballero-mateos Guillermo Arturo cañadas-de la Fuente Department of Gastroenterology and Hepatology San Cecilio University HospitalGranada 18014Spain Department of Nursing Faculty of Health SciencesUniversity of GranadaGranada 18004Spain

Recent advancements in the treatment landscape of ulcerative colitis(UC)have ushered in a new era of possibilities,particularly with the introduction of Janus kinase(JAK)-signal transducer and activator of transcription *** novel agents offer a paradigm shift in UC management by targeting key signaling pathways involved in inflammatory *** approved JAK inhibitors(JAKis),such as tofacitinib,filgotinib,and upadacitinib,clinicians now have powerful tools to modulate immune responses and gene expression,potentially revolutionizing the treatment algorithm for *** trials have demonstrated the efficacy of JAKis in inducing and maintaining remission,presenting viable options for patients who have failed conventional ***-world data support the use of JAKis not only as first-line treatments but also in subsequent lines of therapy,particularly in patients with aggressive disease phenotypes or refractory to biologic *** rapid onset of action and potency of JAKis have broadened the possibilities in the management strategies of UC,offering timely relief for patients with active disease and facilitating personalized treatment *** safety concerns,including cardiovascular risks and infections,ongoing research and post-marketing surveillance will continue to refine our understanding of the risk-benefit profile of JAKis in UC management.

关键词： Ulcerative colitis Janus kinase inhibitors Filgotinib Tofacitinib Upadacitinib