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A Two-Player Coalition Cooperative Scheme for the Bodyguard Allocation Problem

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Journal of Computer Science & Technology 2018年第4期33卷 823-837页

作者： jose Alberto Fernandez-Zepedu daniel Brubeck-Salcedo daniel Fajardo-Delgado Hector Zatarain-Aceves Department of Computer Science Center for Scientific Research and Higher Education of Ensenada Ensenada BC 22860 Mexico Department of Systems and Computation Instituto Technol6gico de Ciudad Guzmdn Guzmdn JAL 49100 Mexico

We address the bodyguard allocation problem （BAP）, an optimization problem that illustrates the conflict of interest between two classes of processes with contradictory preferences within a distributed system. While a class of processes prefers to minimize its distance to a particular process called the root, the other class prefers to maximize it; at the same time, all the processes seek to build a communication spanning tree with the maximum social welfare. The two state-of-the-art algorithms for this problem always guarantee the generation of a spanning tree that satisfies a condition of Nash equilibrium in the system; however, such a tree does not necessarily produce the maximum social welfare. In this paper, we propose a two-player coalition cooperative scheme for BAP, which allows some processes to perturb or break a Nash equilibrium to find another one with a better social welfare. By using this cooperative scheme, we propose a new algorithm called FFC-BAPs for BAP. We present both theoretical and empirical analyses which show that this algorithm produces better quality approximate solutions than former algorithms for BAP.

关键词： bodyguard allocation problem coalitional game graph algorithm Nash equilibrium

Effects of small-scale disturbances and elevation on the morphology,phenology and reproduction of a successful geophyte

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Journal of Plant Ecology 2009年第1期2卷 13-20页

作者： daniel Gomez-Garcıa jose´Azorın AJavier Aguirre Instituto Pirenaico de Ecologı´a-CSIC Apartado.64E-22700 JacaHuescaSpain A´rea de Ingenierı´a Agroforestal.EPSH Universidad de Zaragoza.Ctra Cuarte s/n.E-22071 HuescaSpain

Aims We aimed to find out how a geophyte,Merendera montana,occupies a wide ecological,elevational and climatic *** occurrence in that environmental array is outstanding not only among geophytes but also in the whole flora of the Iberian Peninsula,where only a very few plants show such an apparent ***,we compared morphological and reproductive traits,and frequency of different types of reproduction in disturbed and undisturbed ***,we have analyzed the phenology of this plant by trying to understand how it manages to spread in an exceptional elevational gradient of 2000 m,with contrasting climatic regimes between the mediterranean and the alpine *** We measured the plant density of *** populations in different types of Pyrenean grasslands either with or without small-scale disturbances at seven sites from the basal to the alpine belt(400–2300 m a.s.l.).In each one of these populations,100 individuals—1200 in total—were uprooted to measure their morphological features as well as type and occurrence of ***(flowering and fruiting dates and leaf lifespan)was estimated using 5 years of records in the studied areas and>200 herbarium sheets from the whole altitudinal rank and collected in the last 30 *** in plant densities were analyzed with non-parametric Mann–Whitney U-test;differences in morphological traits,fruit and seed production associated with disturbance,with one-way analysis of covariance test(general linear model).Finally,linear regression analyses were used to determine the relationships between clonal reproduction and elevation and those between flowering,fruiting and senescence and date and *** Findings In all cases,plant density in disturbed grasslands was significantly higher than in undisturbed *** height and weight,bulb depth,leaf width and bulb and root weight were higher in disturbed *** and undisturbed plots were similar

关键词： Spanish Pyrenees Merendera montana functional traits disturbed grasslands

Geriatric epidemiology of trauma in a hospital in Southern Colombia

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Journal of Acute Disease 2017年第1期6卷 33-35页

作者： Yolercy Vsquez Jos daniel charry Juan daniel Ochoa Ana Mara Gmez Karen Herrera Jorman Harvey Tejada jose Domingo Alarcn Department of Family Medicine Faculty of Health SciencesSurcolombiana UniversityNeivaColombia Grupo de Investigación Desarrollo Social Salud Pública y Derechos HumanosSurcolombiana UniversityNeivaColombia Department of Medicine Faculty of Health SciencesFundación Universitaria Navarra-UNINAVARRANeivaColombia. Department of Medicine Faculty of Health SciencesSurcolombiana UniversityNeivaColombia Neuroanesthesiologist Medical Coordinator of Postgraduate Program in Anesthesiology and ReanimationFaculty of Health Sciences-Surcolombiana UniversityNeivaColombia

Objective: To describe the clinical and sociodemographic characteristics of geriatric patients who were treated at a university hospital in southern Colombia. Methods: A database of trauma patients over 65 admitted between June 2014 and December 2015 was constructed. Univariate analysis was performed. Measures of central tendency and dispersion for continuous variables were calculated. Results: A total of 760 patients were analyzed, the median age was 74 years (65–98). The median injury severity score was 9 (4–25) the 71.97% were men, and overall mortality was 25.39%. The 92.10% was blunt trauma, and the main mechanism of injury was falls. Conclusions: Trauma in the elderly is a common condition with high risk of mortality. It is important to know the frequency of these injuries to provide the best possible handling. In our hospital we found that geriatric trauma is a common disease, the main cause is falls without embargos traffic accidents are common in this population.

关键词： Trauma Geriatrics Epidemiology

An all optical approach for comprehensive in-operando analysis of radiative and nonradiative recombination processes in GaAs double heterostructures

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Light(Science & Applications) 2022年第6期11卷 1206-1217页

作者： Fan Zhang jose Fcastaneda Timothy Hgfroerer daniel Friedman Yong-Hang Zhang Mark Wwanlass Yong Zhang Department of Electrical and Computer Engineering The University of North Carolina at CharlotteCharlotteNC 28223USA Songshan Lake Materials Laboratory DongguanGuangdong 523808China Department of Physics Davidson CollegeDavidsonNC 28035USA National Renewable Energy Laboratory GoldenCO 80401USA School of Electrical Computer and Energy EngineeringArizona State UniversityTempeAZ 85287USA Wanlass Consulting NorwoodCO 81423USA

We demonstrate an all optical approach that can surprisingly offer the possibility of yielding much more information than one would expect,pertinent to the carrier recombination dynamics via both radiative and nonradiative processes when only one dominant deep defect level is present in a semiconductor *** applying a band-defect state coupling model that explicitly treats the inter-band radiative recombination and Shockley-Read-Hall(SRH)recombination via the deep defect states on an equal footing for any defect center occupation fraction,and analyzing photoluminescence(PL)as a function of excitation density over a wide range of the excitation density(e.g.,5-6 orders in magnitude),in conjunction with Raman measurements of the LO-phonon plasmon(LOPP)coupled mode,nearly all of the key parameters relevant to the recombination processes can be *** include internal quantum efficiency(IQE),minority and majority carrier density,inter-band radiative recombination rate(Wr),minority carrier nonradiative recombination rate(Wnr),defect center occupation fraction(f)),defect center density(Nt),and minority and majority carrier capture cross-sections(σt andσtM).While some of this information is thought to be obtainable optically,such as IQE and the Wr/Wnr ratio,most of the other parameters are generally considered to be attainable only through electrical techniques,such as current-voltage(Ⅰ-Ⅴ)characteristics and deep level transient spectroscopy(DLTS).Following a procedure developed herein,this approach has been successfully applied to three GaAs double-heterostructures that exhibit two distinctly different nonradiative recombination *** method greatly enhances the usefulness of the simple PL technique to an unprecedented level,facilitating comprehensive material and device characterization without the need for any device processing.

关键词： radiative defect approach

Tribological behaviour of sintered iron based self-lubricating composites

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Friction 2017年第3期5卷 285-307页

作者： jose daniel Biasoli DE MELLO Cristiano BINDER Gisele HAMMES Roberto BINDER Aloisio Nelmo KLEIN Laboratorio de Materiais(LabMat) Universidade Federal de Santa Catarina Florianópolis 88.040-900 SC BrazilLaboratorio de Tribologia e Materiais Universidade Federal de Uberl(a)ndia Uberl(a)ndia 38.400-902 MG Brazil Laboratorio de Materiais(LabMat) Universidade Federal de Santa Catarina Florianópolis 88.040-900 SC Brazil Whirlpool Embraco Unit Joinville 89.219-900 SC Brazil

This work is a review of previous works,presenting and discussing the most important results obtained by an ongoing research program towards the development of innovative,low-cost,self-lubricating composites with a low friction coefficient and high mechanical strength and wear *** emphasis is given to uniaxial die pressing of solid lubricant particles mixed with matrix powders and to metal injection moulding associated with in situ generation of solid lubricant ***,a microstructural model/processing route (powder injection moulding followed by plasma-assisted debinding and sintering) produced a homogeneous dispersion of in situ generated solid lubricant *** nodules of graphite with diameter smaller than 20 μm were formed,constituting a nanostructured stacking of graphite foils with nanometric *** Raman analysis indicated that the graphite nodules were composed of turbostratic 2D graphite having highly misaligned graphene planes separated by large interlamellae *** interplanar distance between the graphene foils and misalignment of these foils were confirmed by transmission electron microscopy and were,probably,the origin of the outstandingly low dry friction coefficient (0.04).The effect of sintering temperature,precursor content,metallic matrix composition and surface finish is also ***,the influence of a double-pressing/double-sintering (DPDS) technique on the tribological performance of self-lubricating uniaxially die-pressed hBN + graphite-Fe-Si-C-Mo composite is also ***,the tribological behaviour of die-pressed Fe-Si-C matrix composites containing 5,7.5 and 10 wt％ solid lubricants (hBN and graphite) added during the mixing step is analysed in terms of mechanical properties and wear ***,the synergy between solid lubricant particles dispersed in a metallic matrix and fluid lubricants in a cooperative mixed lubrication regime is presented.

关键词： tribological behaviour powder metallurgy iron based self-lubricating composites turbostratic graphite

From hepatitis A to E:A critical review of viral hepatitis

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World Journal of Gastroenterology 2021年第16期27卷 1691-1715页

作者： daniel Castaneda Adalberto jose Gonzalez Mohammad Alomari Kanwarpreet Tandon Xaralambos Bobby Zervos Digestive Disease Institute Cleveland Clinic FloridaWestonFL 33331United States Transplant Department Cleveland Clinic FloridaWestonFL 33331United States

Viral infections affecting the liver have had an important impact on humanity,as they have led to significant morbidity and mortality in patients with acute and chronic *** an unknown etiology,the discovery of the viral agents triggered interest of the scientific community to establish the pathogenesis and diagnostic modalities to identify the affected *** the rapid scientific and technological advances in the last centuries,controlling and even curing the infections became a possibility,with a large focus on preventive medicine through ***,a comprehensive understanding of hepatitis A,B,C,D and E is required by primary care physicians and gastroenterologists to provide care to these *** review article describes the epidemiology,pathogenesis,clinical presentation,diagnostic tools and current medication regimens,with a focus on upcoming treatment options and the role of liver transplantation.

关键词： Hepatitis A Hepatitis B Hepatitis C Hepatitis D Hepatitis E Treatment

Coffee Leaf Rust(Hemileia vastatrix)Disease in Coffee Plants and Perspectives by the Disease Control

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Phyton-International Journal of Experimental Botany 2024年第5期93卷 923-949页

作者： Alexis Salazar-Navarro Victor Ruiz-Valdiviezo jose Joya-Dávila daniel Gonzalez-Mendoza Instituto de Ciencias Agrícolas de la Universidad Autónoma de Baja California(ICA-UABC) Nuevo LeónBaja California21705México Laboratorio de Biología Molecular del Instituto Tecnológico Nacional de Tuxtla Gutierrez(TecNM) Tuxtla GutierrezChiapas29050México Facultad de Ciencias Agronómicas Campus V.Universidad Autónoma de Chiapas(UNACH) VillafloresChiapas30470México

Coffee Leaf Rust(CLR)is caused by Hemileia vastatrix in Coffea *** is one of the most dangerous phytopathogens for coffee plantations in terms of coffee productivity and coffee cup *** this review,we resume the problem of CLR in Mexico and the pathogenesis of *** review abord plant-pathogen interactions which lead a compatible or incompatible interactions and result in CLR disease or resistance,*** review abord Coffea *** response pathways involved in *** ***,current measures to control *** proliferation and germination were aborded focused on phytosanitary actions,and biological and chemical ***,new trendlines to reduce the impact of CLR as nanoparticles and nanotechnology were analyzed.

关键词： Coffee leaf rust Coffea arabica pathogenesis nanoparticles biological control

Vacuum promotes metabolic shifts and increases biogenic hydrogen production in dark fermentation systems

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 513-521页

作者： Haifa RAJHI daniel PUYOL Mirna C. MARTiNEZ Emiliano E. DLAZ jose L. SANZ Department of Molecular Biology University Autonoma of Madrid Madrid 28049 Spain Section of Chemical Engineering University Autonoma of Madrid Madrid 28049 Spain MYGEN Laboratory Cantoblanco Madrid 28049 Spain

The successful operation of any type of hydrogen-producing bioreactor depends on the performance of the microorganisms present in the system. Both substrate and partial gas pressures are crucial factors affecting dark fermentation metabolic pathways. The main objective of this study was to evaluate the impact of both factors on hydrogen production using anaerobic granular sludge as inoculum and, secondly, to study the metabolic shifts of an anaerobic community subjected to low partial gas pressures. With this goal in mind, seven different wastewater （four synthetic media, two industrial waste- water, and one domestic effluent） and the effect of applying vacuum on the systems were analyzed. The application of vacuum promoted an increase in the diversity of hydrogen-producing bacteria, such as Clostridium, and promoted the dominance of acetoclasticover hydrogenotrophic methanogens. The application of different media promoted a wide variety of metabolic pathways. Nevertheless, reduction of the hydrogen partial pressure by application of vacuum lead to further oxidation of reaction intermediates irrespective of the medium used, which resulted in higher hydrogen and methane production, and improved the COD removal. Interestingly, vacuum greatly promoted biogenic hydrogen production from a real wastewater, which opens possibilities for future application of dark fermentation systems to enhance biohydrogen yields.

关键词： dark fermentation biohydrogen wastewaters vacuum

GIS-based study of the evolution of the IGN's strong motion network of mainland Spain and the balearics

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Geodesy and Geodynamics 2021年第4期12卷 279-287页

作者： jose-Lazaro Amaro-Mellado daniel Anton Juan-Manuel Alcalde Instituto Geografico Nacional Servicio Regional en AndaluciaSeville 41013Spain Departamento de Ingenierfa Grafica Universidad de SevillaSeville 41092Spain Research Group TEP970:Innovacion Tecnoldgica Sistemas de Modelado 3D y Diagnosis Energetica en Patrimonio y Edificacidn'Departamento de Expresion Grafica e Ingenieria en la EdificacionEscuela Tecnica Superior de Ingenieria de EdificacionUniversidad de Sevilla4A Reina Mercedes AvenueSeville 41012Spain The Creative and Virtual Technologies Research Laboratory School of ArchitectureDesign and the Built EnvironmentNottingham Trent University50 Shakespeare StreetNottingham NG14FQUK Escuela Superior de Ingenieria y Tecnologia Universidad Intemacional de La Rioja737 La Paz AvenueLogrono 26006Spain Instituto Geografico Nacional Red Sismica NacionalMadrid 28003Spain

In some countries with seismicity,an adequate detection network is essential to assess seismic *** Instituto Geografico Nacional(National Geographic Institute/IGN)of Spain manages a strong motion network distributed throughout the whole country and an earthquake detection network composed of velocity *** paper aims at studying the development of the strong motion network of the Spanish National Seismic Network(focusing on mainland Spain and the Balearics)in the last three decades.A Geographic Information System(GIS)has been implemented to integrate the attributes from the IGN’s database concerning the earthquake catalogue,seismograph and accelerometer networks,which enabled to analyse the data and map the distribution of detection equipments in the *** irregularly distributed Spanish strong motion network was greatly expanded from 1990 to *** the past decade,it developed at a slower rate,but more modern technology was implemented.

关键词： Strong motion Accelerometer network Spanish national seismic network Earthquake catalogue GIS