检索结果-南通市图书馆

An ACO-RFD hybrid method to solve NP-complete problems

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer science 2013年第5期7卷 729-744页

作者： pablo RABANAL Ismael RODRIGUEZ Fernando RUBIO Dept. sistemas Inforrnaiticos y Computacion Facultad de Informatica Universidad Complutense de Madrid Madrid 28040 Spain

In this paper we hybridize ant colony optimiza- tion （ACt） and river formation dynamics （RFD）, two related swarm intelligence methods. In ACt, ants form paths （prob- lem solutions） by following each other＇s pheromone trails and reinforcing trails at best paths until eventually a single path is followed. On the other hand, RFD is based on copy- ing how drops form rivers by eroding the ground and de- positing sediments. In a rough sense, RFD can be seen as a gradient-oriented version of ACt. several previous experi- ments have shown that the gradient orientation of RFD makes this method solve problems in a different way as ACt. In particular, RFD typically performs deeper searches, which in turn makes it find worse solutions than ACt in the first exe- cution steps in general, though RFD solutions surpass ACt solutions after some more time passes. In this paper we try to get the best features of both worlds by hybridizing RFD and ACt. We use a kind of ant-drop hybrid and consider both pheromone trails and altitudes in the environment. We apply the hybrid method, as well as ACt and RFD, to solve two NP-hard problems where ACt and RFD fit in a different manner： the traveling salesman problem （TsP） and the prob- lem of the minimum distances tree in a variable-cost graph （MDV）. We compare the results of each method and we an- alyze the advantages of using the hybrid approach in each case.

关键词： river formation dynamics ant colony optimization heuristic algorithms NP-hard problems

Parallel array with axially coded light-sheet microscope

在线全文

学校读者我要写书评

暂无评论

Light(science & Applications) 2020年第1期9卷 1387-1388页

作者： pablo Loza-Alvarez ICFO-The Institute of Photonic sciences The Barcelona Institute of Science and Technology08860 CastelldefelsBarcelonaSpain

A parallel array of frequency modulated light sheets results in a scanning-less light sheet microscope capable of fast volumetric imaging.

关键词： array light axial

safety of digoxin in nonagenarian patients with atrial fibrillation:lessons from the spanish Multicenter Registry

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2021年第10期18卷 809-815页

作者： pablo Domínguez-Erquicia sergio Raposeiras-Roubín Emad Abu-Assi María Cespón-Fernández David Alonso-Rodríguez santiago Jesús Camacho-Freire Naiara Cubelos-Fernández Álvaro López-Masjuán Ríos María Melendo-Viu andrésÍñiguez-Romo Department of Cardiology University HospitalÁlvaro CunqueiroVigoSpain Health Research Institute Galicia sur VigoSpain Department of Cardiology University Hospital of LeónLeónSpain Department of Cardiology University Hospital Juan Ramón JiménezHuelvaSpain

BACKGROUND The association between digoxin and mortality is an unclear *** older patients with atrial fibrillation(AF),where use of digoxin is frequent,the evidence of its safety is *** aim is to assess the safety of digoxin in nonagenarian patients with *** We evaluated data from 795 nonagenarian patients with non-valvular AF from the spanish Multicenter *** analyzed the relationship between digoxin and all-cause mortality with the Cox proportional-hazards *** Follow-up was 27.7±18.3 *** age was 92.5±3.8 years,and 71%of nonagenarian patients were *** was not associated with increased risk of mortality[adjusted hazard ratio(aHR)=1.16,95%CI:0.96−1.41,P=0.130].However,we found a significant increase in mortality in the subgroup with estimated glomerular filtration rate(eGFR)subgroups of eGFR(30−59 mL/min per 1.73 m^(2) and≥60 mL/min per 1.73 m^(2)).When exploring the risk of mortality according to sex,male subgroup was associated with an in-crease in mortality(aHR=1.48,95%CI:1.02−2.14,P=0.041).This was not observed in females subgroup(aHR=1.03,95%CI:0.81−1.29,P=0.829).Based on the presence or absence of heart failure,we did not find significant differences(aHR=1.20,95%CI:0.87−1.65,P=0.268 ***=1.15,95%CI:0.90−1.47,P=0.273,respectively).CONCLUsIONs In our large registry of nonagenarian patients with AF,we did not find an association between digoxin and mortality in the total ***,in the subgroup analyses,we found an increase in mortality with the use of digoxin in men and in patients with an eGFR<30 mL/min per 1.73 m^(2).

关键词： patients digoxin fibrillation

Diffusion dynamics and characterization of attogram masses in optically trapped single nanoparticles using laser-induced plasma imaging

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第5期16卷 7470-7480页

作者： pablo Purohit Francisco J.Fortes Javier Laserna UMALAsERLAB Departamento de Química AnalíticaUniversidad de MálagaC/Jiménez Fraud 4Malaga 29010Spain Niels Bohr Institute University of CopenhagenBlegdamsvej 172100 CopenhagenDenmark

In the present work,a wavelength-selected plasma imaging analysis system is presented and used to track photons emitted from single-trapped nanoparticles in air at atmospheric *** isolated nanoentities were atomized and excited into plasma state using single nanosecond laser *** use of appropriate wavelength filters alongside time-optimized acquisition settings enabled the detection of molecular and atomic emissions in the *** photon detection efficiency of the imaging line resulted in a signal>400 times larger than the simultaneously-acquired dispersive spectroscopy *** increase in sensitivity outlined the evolution of diverse physicochemical processes at the single particle scale which included heat and momentum transfer from the plasma into the particle as wells as chemical *** imaging detection of excited fragments evidenced different diffusion kinetics and time frames for atoms and molecules and their influence upon both the spectroscopic emission readout and fabrication processes using the plasma as a ***,the origin of molecular species,whether naturally-occurring or derived from a chemical reaction in the plasma,could also be studied on the basis of compositional gradients found on the *** of detection for the inspected species ranged from tens to hundreds attograms,thus leading to an exceptional sensing principle for single nanoentities that may impact several areas of science and technology.

关键词： single nanoparticle inspection wavelength-selected laser-induced plasma imaging laser fabrication attogram characterization atomic/molecular diffusion

Bridging Methods for Atomistic-to-Continuum Coupling and Their Implementation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Computational Physics 2010年第4期7卷 831-876页

作者： pablo seleson Max Gunzburger Department of scientific Computing Florida State UniversityTallahasseeFL 32306-4120USA

several issues connected with bridging methods for atomistic-to-continuum(AtC)coupling are *** coupling approaches using various energy blending models are studied as well as the influence that model parameters,blending functions,and grids have on simulation *** use the Lagrange multiplier method for enforcing constraints on the atomistic and continuum displacements in the bridge *** also show that continuum models are not appropriate for dealing with problems with singular loads,whereas AtC bridging methods yield correct results,thus justifying the need for a multiscale *** investigate models that involve multiple-neighbor interactions in the atomistic region,particularly focusing on a comparison of several approaches for dealing with Dirichlet boundary conditions.

关键词： Multiscale modeling atomistic-to-continuum coupling boundary treatment

Comparing techniques for measuring corticosterone in tadpoles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2015年第5期61卷 835-845页

作者： pablo BURRACO Rosa ARRIBAs saurabh s. KULKARNI Daniel R. BUCHHOLZ Ivan GOMEZ-MEsTRE Department of Wetland Ecology Estacion Biologica de Dofiana (EBD-CSIC) C/Americo Vespucio s/n 41092 Sevilla Spain Department of Pediatrics Yale School of Medicine Yale University New Haven CT 0651 USA Department of Biological sciences University of Cincinnati Cincinnati OH 45221 USA

Glucocorticoids play a key role in mediating stress responses in vertebrates. Corticosterone （CORT） is the main glucocorticoid produced in amphibians, birds, and reptiles, and regulates several metabolic functions. The most common methods for quantifying CORT are competitive binding immunoassays： radioimmunoassay （RIA） and enzyme immunoassay （EIA）. RIA has been broadly used since the 1980＇s but it requires radioactivity. Commercial EIA kits permit quantifying hormone levels without radioactivity although the requirement for a larger sample volume may be a strong limitation for measurements involving larval amphibians. Here we used Xenopus laevis tadpoles to compare the performance of three commonly used procedures for determination of CORT： RIA on a chloroform extract of whole-body homogenate, EIA on plasma, and EIA on supematant of whole-body homogenate. We treated tadpoles with exogenous CORT at 0, 25, 50, and 100 nM. RIA could distinguish between 0 and 25 nM, and EIA on plasma between 0 and 50 nM, whereas whole-body homogenate EIA only detected significant differences between 0 and 100 riM. Each procedure presents advantages and disadvantages regarding sensitivity, the use of radioactivity, sample size, handling time, and economic cost. RIA is preferred when studying small-bodied animals from which blood samples cannot be obtained. When CORT level differences are intermediate and blood sampling is possible, EIA on plasma is a good non-radioactive alternative. EIA on whole-body homogenates may be useful to assess qualitative changes in CORT levels when considerable differences are expected. Finally, we discuss our findings in the context of previous studies on CORT in amphibians [Current Zoology 61 （5）： 835-845, 2015].

关键词： Corticosterone Radioimmunoassay Enzyme immunoassay Glucocorticoids Amphibians stress

Editorial for a special issue on graphene and 2D alternative materials:From preparation to potential applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Materials science 2022年第1期4卷 1-2页

作者： pablo Ares Felix Zamora Departamento de Fisica de la Materia Condensada and Condensed Matter Physics Center(IFIMAC) Universidad Autonoma de Madrid Madrid28049Spain Departamento de Quimica Inorganica Condensed Matter Physics Center(IFIMAC)and Institute for Advanced Research in Chemical Sciences(IAdChem)Universidad Autonoma de MadridMadrid28049Spain Instituto Madrileno de Estudios Avanzados en Nanociencia(IMDEA-Nanociencia) CantoblancoMadrid28049Spain

The isolation of graphene and subsequent studies showed that obtaining atomically thin crystalline sheets was feasible and possessed extraordinary *** result opened the door to an entirely new family of materials known as two-dimensional or 2D *** in this field is intense:the emergence of new 2D materials,the properties of their combinations and the ability of graphene to reinvent itself,showing novel and exciting properties,make it likely that this field will continue to be one of the leading topics of materials science and condensed matter physics.

关键词： preparation entirely crystalline

在线全文

学校读者我要写书评

暂无评论

银行监管面临的两个事实和一个谬论

中国金融 2024年第7期 15-17页

作者：巴勃罗·埃尔南德斯·德·科斯张林(译) 巴塞尔银行监管委员会西班牙银行《中国金融》杂志

多年来,在欧洲金融监管专业智库Eurofi举办的各种活动中,人们一直热衷于讨论巴塞尔银行监管委员会(以下简称巴塞尔委员会)的工作以及更加广泛的审慎监管问题。粗略地回顾一下Eurofi之前召开的会议,大家就不难发现这样一些主题:“巴塞尔... 详细信息

多年来,在欧洲金融监管专业智库Eurofi举办的各种活动中,人们一直热衷于讨论巴塞尔银行监管委员会(以下简称巴塞尔委员会)的工作以及更加广泛的审慎监管问题。粗略地回顾一下Eurofi之前召开的会议,大家就不难发现这样一些主题:“巴塞尔协议Ⅲ对欧盟金融活动的影响”(2019年)、“在欧盟实施巴塞尔协议:尚存的挑战和时机”(2021年).

关键词：巴塞尔协议巴塞尔委员会审慎监管金融监管银行监管巴塞尔银行监管委员会欧盟

Marriage Market with Indifferences: A Linear Programming Approach

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research society of China 2023年第1期11卷 219-242页

作者： Noelia Juarez pablo A.Neme Jorge Oviedo Instituto de Matemática Aplicada san Luis IMASLRedNIEUniversidad Nacional de San Luis and CONICETD5700HHWSan LuisRepublica Argentina

We study stable and strongly stable matchings in the marriage market with indifference in their *** characterize the stable matchings as integer extreme points of a convex *** give an alternative proof for the integrity of the strongly stable matching ***,we compute men-optimal(women-optimal)stable and strongly stable matchings using linear *** preferences are strict,we find the men-optimal(women-optimal)stable matching.

关键词： Matching markets The marriage market with indifferences Optimal stable matchings Linear programming