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On the numerical solution to the truncated discrete SPH formulation of the hydrostatic problem

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Journal of Hydrodynamics 2020年第4期32卷 699-709页

作者： pablo Eleazar Merino-Alonso Fabricio Macia Antonio Souto-Iglesias Mathematical Modeling Analysisand Simulation Applied to Engineering Research Group(M2ASAI)Universi dad politecnica de Madrid(UPM)School of marine engineering(ETSIN)MadridSpain Marine and Hydrodynamical Model Basin Research Group(CEHINAV) Universidad Politecnica de Madrid(UPM)School of Marine Engineering(ETSIN)MadridSpain

The aim of this work is to study the solution of the smoothed particle hydrodynamics(SPH)discrete formulation of the hydrostatic problem with a free *** problem,in which no time dependency is considered,takes the form of a system of linear *** particular,the problem in one dimension is *** focus is set on the convergence when both the particle spacing and the smoothing length tend to zero by keeping constant their *** of this ratio of the order of one,corresponding to a limited number of neighbors,are of practical ***,the problem in which each particle has one single neighbor at each side is *** explicit expressions of the numerical solution and the quadratic error are provided in this *** expression of the quadratic error demonstrates that the SPH solution does not converge to the exact one in general under the specified *** this case,the error converges to a residue,which is in general large compared to the norm of the exact *** cases with two and three neighbors are also *** analytical study in the case of two neighbors is performed,showing how the kernel influences the accuracy of the solution through modifying the condition number of the referred system of linear *** addition to that,a numerical investigation is carried out using several Wendland kernel *** two and three neighbors are involved it is found that the error tends in most cases to a small limiting value,different from zero,while divergent solutions are also found in the case of two neighbors with the Wendland Kernel *** cases with more neighbors are also *** general,the Wendland Kernel C2 turns out to be the worst choice,as the solution is divergent for certain values of the ratio between the particle spacing and the smoothing length,associated with an ill-conditioned matrix.

关键词： Smoothed particle hydrodynamics(SPH) convergence water-at-rest problem hydrostatic tank,free surface kernel truncation

Risk Transfer for Populations in Precarious Urban Environments

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International Journal of Disaster Risk Science 2020年第1期11卷 74-86页

作者： Juan pablo Sarmiento Ana María Torres-Munoz Extreme Events Institute/Disaster Risk and Resilience in the Americas(DRRA) Florida International UniversityMiamiFL 33199USA

This study explores risk transfer options that precarious and marginal urban communities could use to protect themselves from future damages and losses generated by socio-natural hazards and disasters at the individual and community levels. The design is framed within an evidence-based disaster risk reduction(DRR) strategy and follows the case study research approach. We analyze the2018 Neighborhood Approach for DRR programming evaluation carried out in four Latin American cities’ informal settlements and review relevant risk transfer experiences aimed at vulnerable populations. We calculate the pure risk premium for the four cases selected, using a previous catastrophe risk assessment for earthquakes and landslides. We propose three risk transfer options based on our analysis:(1) voluntary collective insurance;(2) structural reinforcement with a comprehensive housing insurance;and(3) hybrid parametric insurance. Risk transfer mechanisms conventionally focus on residual risk management. Here, due to the precariousness of the analyzed urban settings, the proposed alternatives go beyond the management of just residual risk to positively impact the beneficiaries’ quality of life and the reduction of the built environment’s physical vulnerability in the short and medium terms. Our study proposes a prospective estimation of future risk despite the limitations of data availability. This study opens a window to new approaches and proposes a systematic process to design DRR policy aimed at the poor and vulnerable strata of society.

关键词： Case study research Catastrophe risk assessment Informal settlements Risk transfer Urban precariousness Urban risk

Atrial fibrillation in the elderly

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Journal of Geriatric Cardiology 2019年第1期16卷 49-53页

作者： pablo Díez-Villanueva Fernando Alfonso Department of Cardiology Hospital Universitario de la Princesa

Atrial fibrillation(AF)is the most common arrhythmia in elderly population,with age being one of the most important factors involved in its *** disturbances may be present on the surface electrocardiogram before AF onset in some *** this arrhythmia is diagnosed,antithrombotic therapy is mandatory in most cases,as this is the only treatment that has demonstrated to improve *** increases both the risk of thromboembolic and bleeding complications,while benefits from anticoagulant therapy outweigh that from bleeding in most scenarios,also in very elderly ***,elderly patients with AF are often ***-vitamin K antagonist oral anticoagulants have emerged as an alternative to vitamin K antagonists,with significant less adverse events and better profile in terms of efficacy and *** conditions related to age should be carefully evaluated in these patients(including frailty,comorbidity and polypharmacy)to ensure an individualized clinical and therapeutic approach.

关键词： Atrial fibrillation Antithrombotic therapy Frailty Non-vitamin K antagonist oral anticoagulants The elderly

Conserved Curvature of RNA Polymerase Ⅰ Core Promoter Beyond rRNA Genes: The Case of the Tritryps

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Genomics, Proteomics & Bioinformatics 2015年第6期13卷 355-363页

作者： pablo Smircich María Ana Duhagon Beatriz Garat Molecular Interactions Laboratory School of Sciences University of the Republic Genetics Departament School of Medicine University of the Republic

In trypanosomatids, the RNA polymerase I （RNAPI）-dependent promoters controlling the ribosomal RNA （rRNA） genes have been well identified. Although the RNAPI transcription machinery recognizes the DNA conformation instead of the DNA sequence of promoters, no con- formational study has been reported for these promoters. Here we present the in silico analysis of the intrinsic DNA curvature of the rRNA gene core promoters in Trypanosoma brucei, Trypanosoma cruzi, and Leiskmania major. We found that, in spite of the absence of sequence conservation, these promoters hold conformational properties similar to other eukaryotic rRNA promoters. Our results also indicated that the intrinsic DNA curvature pattern is conserved within the Leishmania genus and also among strains of T. cruzi and T. brucei. Furthermore, we analyzed the impact of point mutations on the intrinsic curvature and their impact on the promoter activity. Furthermore, we found that the core promoters of protein-coding genes transcribed by RNAPI in T. brucei show the same conserved conformational characteristics. Overall, our results indicate that DNA intrinsic curvature of the rRNA gene core promoters is conserved in these ancient eukaryotes and such con- served curvature might be a requirement of RNAPI machinery for transcription of not only rRNA genes but also protein-coding genes.

关键词： Intrinsic curvature RNA polymerase I Core promoter Trypanosoma Leishmania

Is X(3872) a bound state?

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Chinese Physics C 2019年第12期43卷 115-120页

作者： pablo G.Ortega Enrique Ruiz Arriola Grupo de Fisica Nuclear and Instituto Universitario de Fisica Fundamental y Matematicas(IUFFyM) Universidad de SalamancaE-37008 SalamancaSpain Departamento de Fisica Atomica Molecular y Nuclear and Instituto Carlos I de Fisica Teorica y ComputacionalUniversidad de GranadaE-18071 GranadaSpain

All existing experimental evidence for the bound state nature of X(3872)relies on observing its decay products,which are measured with a finite experimental mass resolution that is typically△m≥2 MeV,and much larger than its alleged binding energy,BX=0.00(18)*** the other hand,we have found recently that there is a clear cancellation in the 1^++channel of the invariant DD^*mass around the threshold between continuum and the bound *** is very much like a similar cancellation in the proton-neutron continuum with the deuteron in the 1^++*** on comparative fits with a common Tsallis distribution of the experimental cross-sections for prompt production of deuterons and X(3872)in pp collisions with a finite pT,we find a strong argument for questioning the bound state nature of this state,which also suggests that the large observed production rate could be consistent with a half-bound state.

关键词： charmonium molecular states particle production Tsallis distribution

Triply heavy baryons in the constituent quark model

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Chinese Physics C 2020年第2期44卷 33-41页

作者： Gang Yang Jialun Ping pablo GOrtega Jorge Segovia Department of Physics and State Key Laboratory of Low-Dimensional Quantum Physics Tsinghua UniversityBeijing 100084China Department of Physics and Jiangsu Key Laboratory for Numerical Simulation of Large Scale Complex Systems Nanjing Normal UniversityNanjing 210023China Grupo de Física Nuclear and Instituto Universitario de Física Fundamental y Matemáticas(IUFFyM) Universidad de SalamancaE-37008 SalamancaSpain Departamento de Sistemas Físicos Químicos y NaturalesUniversidad Pablo de OlavideE-41013 SevillaSpain

The constituent quark model is used to compute the ground and excited state masses of QQQ baryons containing either c or b *** quark model parameters previously used to describe the properties of charmonium and bottomonium states were used in this *** non-relativistic three-body bound state problem is solved by means of the Gaussian expansion method which provides sufficient accuracy and simplifies the subsequent evaluation of the matrix *** low-lying states with quantum numbers J^P=1/2^±,3/2^±,5/2^±and 7/2^+are *** compare the results with those obtained by the other theoretical *** is a general agreement for the mass of the ground state in each sector of triply heavy ***,the situation is more puzzling for the excited states,and appropriate comments about the most relevant features of our comparison are given.

关键词： Quantum Chromodynamics quark models properties of baryons exotic baryons

Myelin lipid deficiency:a new key driver of Alzheimer’s disease

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Neural Regeneration Research 2023年第1期18卷 121-122页

作者： Shulan Qiu Juan pablo Palavicini Xianlin Han Barshop Institute for Longevity and Aging Studies Division of DiabetesDepartment of MedicineUniversity of Texas Health Science Center at San AntonioSan AntonioTXUSA

Lipids play essential biological functions that include acting as components of biological membranes,energy storage,signaling,nutrients,transporters,enzyme activators,among *** with the multiple research methods to assess DNA,RNA,and protein content,location,and function in cells,there are relatively fewer methods to study ***,lipid-oriented mechanistic studies remain rare and challenging.

关键词： Alzheimer rare challenging

Secondary seed dispersal by dung beetles in an Amazonian forest fragment of Colombia:influence of dung type and edge effect

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Integrative Zoology 2011年第4期6卷 399-408页

作者： Carolina SANTOS-HEREDIA Ellen ANDRESEN pablo STEVENSON Department of Biological Sciences University of the AndesBogotaColombia Center for Ecosystem Research at the National Autonomous University of Mexico MoreliaMexico

Seeds of many plant species are secondarily dispersed by dung beetles,but the outcome of this interaction is highly *** is known about how certain anthropogenic disturbances affect this plant-animal *** aims of this study were to assess the effect of dung type on secondary dispersal by dung beetles in a forest fragment,and to determine whether this interaction is affected by edge *** pitfall traps,we captured dung beetles attracted to dung of 2 frugivorous mammals:woolly monkeys and howler *** found differences between both dung beetle assemblages,but these differences were not consistent in *** seeds surrounded by both dung types,we carried out a field experiment using seeds of 2 plant *** found that the probability of secondary dispersal by dung beetles was higher for seeds placed in woolly monkey ***,we carried out a field experiment using plastic beads as seed mimics to assess edge *** found that secondary seed dispersal by dung beetles was negatively affected by *** disruption of plant-animal interactions along anthropogenic forest edges could have long-term negative effects on forest dynamics by affecting processes of regeneration.

关键词： fragmentation plant-animal interaction Scarabaeidae seed fate

Linking plant metabolism and immunity through methionine biosynthesis

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Molecular Plant 2022年第1期15卷 6-8页

作者： Francisco Escaray Amelia Felipo-Benavent pablo Vera Instituto de Biología Molecular y Celular de Plantas Universidad Politécnica de Valencia-C.S.I.CCiudad Politécnica de la InnovaciónEdificio 8EIngeniero Fausto Elios/n46022 ValenciaSpain

Plants respond to pathogenic cues with a transcriptional reprog-ramming that leads to de novo production of defense-related pro-teins and a huge variety of secondary metabolites(e.g.,phyto-alexins,phenolics,etc.).Activation of these host defenses,which contribute to halt the intruder as part of the resistance,im-plies an increased demand for metabolic energy and carbon skel-etons derived from primary metabolism(Bolton,2009).

关键词： metabolism immunity Bolton