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Some Smoothness Results for Classical Problems in Optimal Design and Applications

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Chinese Annals of Mathematics,Series B 2015年第5期36卷 703-714页

作者： Juan CASADO-diaz Dpto.de Ecuaciones Diferenciales y Analisis Numerico University of Seville41012 SevillaSpain

The author considers two classical problems in optimal design consisting in maximizing or minimizing the energy corresponding to the mixture of two isotropic materials or two-composite material. These results refer to... 详细信息

关键词： Optimal design Two-phase material Non-existence Relaxation

Changes in Olsen P in Relation to P Balance in Contrasting Agricultural Soils

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Pedosphere 2016年第5期26卷 636-642页

作者： Isabel diaz Jose TORRENT Departamento de Ingeniería Aeroespacial y Mecánica de Fluidos Escuela Tdcnica Superior de Ingeniería Agronómica(ETSIA)Universidad de SevillaCtra de Utrera km 141013 Sevilla(Spain) Departamento de Agronomia Universidad de CordobaEdificio C4Campus de Rabanales14071 Cordoba(Spain)

Maintaining soil phosphorus （P） at adequate levels for plant growth requires assessing how the long-term P balance （viz., the difference between P inputs and outputs） results in changes in soil test P. The hypothesis that routinely measured soil properties can help predict the conversion factor of P balance into Olsen P was tested at 39 sites in agricultural areas of the Mediterranean region in Spair~. A set of soil samples from each site was analyzed for Olsen P, inorganic P （P extracted using 0.5 mol L-1 H2SO4）, pseudototal P （P extracted using 0.5 mol L-1 H2SO4 following ignition at 550 ~C）, and organic P （the difference between pseudototal P and inorganic P）. Organic and Olsen P were uncorrelated in most of the 39 soil sets, which suggests that organic P content changed little with P inputs and outputs. The slopes of the regression lines of Olsen P against pseudototal and inorganic P, which were used as two different measures of the conversion factor, ranged widely （from 0.03 to 0.25 approximately）, with their average values （about 0.10） being similar to those found in long-term experiments conducted in temperate areas. Neither conversion factor was significantly correlated with any routinely measured soil property; however, the conversion factor for inorganic P was significantly lower for calcareous soils than for noncalcareous soils. Our negative results suggest the need to isolate the influence of soil properties from that of management systems and environmental factors relating to P dynamics in future studies.

关键词： calcareous soils conversion factor inorganic P noncalcareous soils organic P pseudototal P soil property soil test P

Urokinase-type plasminogen activator promotes synaptic repair in the ischemic brain

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Neural Regeneration Research 2018年第2期13卷 232-233页

作者： ariel diaz manuel yepes department of neurology and center for neurodegenerative disease emory university school of medicineAtlantaGAUSA division of neuropharmacology and neurologic diseases yerkes national primate research centerAtlantaGAUSA department of neurology veterans affairs medical centerAtlantaGAUSA

The central nervous system has a very high energy requirement. Accord- ingly, despite representing only 2% of the body＇s mass, the brain uses 20% of the total oxygen consumption. Importantly, because most of this energy is used to maintain synaptic activity, even a mild decrease in its supply to the brain has deleterious implications for synaptic function.

关键词： Urokinase-type plasminogen activator promotes synaptic repair in the ischemic brain AR TSP OGD LRP

Avian preference for close proximity to human habitation and its ecological consequences

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Current Zoology 2018年第5期64卷 623-630页

作者： Anders Pape MOLLER Mario diaz Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Pari-Saclay 0rsay Cedex F-91400 France Department of Biogeography and Global Change (BGC-MNCN-CSIC) National Museum of Natural Sciences CSIC c/Serrano 155bis Madrid E-28006 Spain

Human proximity often have negative consequences for wildlife. However, animals may also benefit from human proximity in terms of availability of resources and protection against predators and parasites. We recorded the distance between all birds detected during the breeding season along 18 5-kin transects and the nearest inhabited house in three areas of 50 km2 in Spain, France, and Denmark. More than three quarters of birds were located closer than 100 m to the nearest house, while the null expectation was less than a third. Mean distance for species was correlated with degree of bird urbanization and with flight initiation distance. Habitat specialist species with small breeding territories tended to live closer to houses. Birds from species having more broods per year, larger annual fecundity and lower nest predation rate lived closer to human habitation. Breeding range size, population density, and continental breeding population sizes were larger for species living closer to human habitation. Most relationships between distance to houses and bird traits had a strong phylogenetic signal, but most additive trait effects remained after phylogenetic correction. Proximity to human habitation was a main driver of the distribution of birds, with most individuals and species tightly linked to inhabited houses. Living close to human habitation was associated with success in the colonization of urban habitats and with consistent changes in distribution, abundance, behavior, and life history. Replicated measurements of the spatial and tempo- ral variation in these distributions may be useful for monitoring and analyzing the ongoing process of organisms＇ urbanization.

关键词： birds distance to nearest house flight initiation distance humans refuge urbanization.

Analytical Solution for Waves Propagation in Heterogeneous Acoustic/Porous Media. Part I: The 2D Case

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Communications in Computational Physics 2010年第3期7卷 171-194页

作者： Julien diaz Abdelaaziz Ezziani Project-team Magique-3D INRIA Bordeaux Sud-Ouest LMA Pau CNRS UMR 5142I.P.R.A-Universit´e de Pau et des Pays de l’Adouravenue de l’Universit´e BP 1155-64013 PAU CEDEXFrance

Thanks to the Cagniard-de Hoop’s method we derive the solution to theproblem of wave propagation in an infinite bilayered acoustic/poroelastic media, wherethe poroelastic layer is modelled by the biphasic Biot’s model. This first part is dedi-cated to solution to the two-dimensional problem. We illustrate the properties of thesolution, which will be used to validate a numerical code.

关键词： Biot’s model poroelastic waves acoustic waves acoustic/poroelastic coupling ana-lytical solution Cagniard-de Hoop’s technique 2D

Invasive-invaded system of non-Lipschitz porous medium equations with advection

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International Journal of Biomathematics 2021年第7期14卷 299-327页

作者： Jose Luis diaz Palencia Escuela Politecnica Superior Universidad Francisco de Vitoria Ctra.Pozuelo-Majadahonda Km 1 80028223Pozuelo de AlarconMadrid

This work provides analytical results towards applications in the field of invasive-invaded systems modeled with nonlinear diffusion and with *** results focus on showing regularity,existence and uniqueness of weak solutions using the condition of a nonlinear slightly positive parabolic operator and the reaction-absorption monotone *** coupling in the reaction-absorption terms,that characterizes the species interaction,impedes the formulation of a global comparison principle that is shown to exist ***,this work provides analytical solutions obtained as selfsimilar minimal and maximal profiles.A propagating diffusive front is shown to exist until the invaded specie notes the existence of the *** the desertion of the invaded st arts,the diffusive front vanishes globally and the nonlinear diffusion concentrates only on the propagating tail which exhibits finite ***,the invaded specie is shown to exhibit an exponential decay along a characteristic *** exponential decay is not trivial in the nonlinear diffusion case and confirms that the invasive continues to feed on the invaded during the desertion.

关键词： Nonlinearity reaction absorption coupled system diffusion porous media

Efficacy and safety of Chlorella supplementation in adults with chronic hepatitis C virus infection

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World Journal of Gastroenterology 2013年第7期19卷 1085-1090页

作者： Jose Azocar Arley diaz Northgate Medical Center SpringfieldMA01103United States

AIM:To evaluate the safety and efficacy of Chlorella in 18 patients chronically infected with hepatitis C virus(HCV) genotype ***:Eighteen adults with chronic infection by HCV genotype 1 received daily oral supplementation of Chlorella for 12 *** in the RNA levels of HCV,as well as those of aspartate aminotransferase(AST) and alanine aminotransferase(ALT) levels were evaluated following this treatment *** t tests were conducted to compare the means of the different variables at the beginning and end of the *** effects and quality of life aspects were also compared between weeks 0 and 12 of the study ***:A majority 84.61% of the patients had a significant decrease in their ALT levels from week 0 to week *** of side effects showed that Chlorella was well *** of life assessment showed that 76.9 of the participants reported an improvement in their energy levels and 46.1% reported an improvement in their perception of general *** 69.23% also showed a decrease in their AST levels,this was not statistically *** patients that exhibited an improvement in their ALT and AST levels also showed a tendency toward a decreased HCV viral *** HCV RNA levels showed a decrease in 69.23% of the patients,which along with changes in AST/ALT ratios from week 0 to week 12,these results were not statistically ***:Chlorella supplementation was well tolerated in patients with chronic HCV and associated with a significant decrease in ALT liver enzyme levels.

关键词： Chlorella Hepatitis C virus Interferon Aspartate and alanine aminotransferase Ratio

Niche segregation, competition, and urbanization

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Current Zoology 2018年第2期64卷 145-152页

作者： Anders PAPE MФLLER Mario diaz Ecologie Systematique Evolution CNRS Universite Paris-Sud AgroParisTech Universite Pari-Saclay OrsayCedex F-91400 France Department of Biogeography and Global Change (BGC-MNCN-CSIC) NationalMuseum of Natural Sciences CSIC c/Serrano 155bis Madrid E-28006 Spain

Urbanization of species is an ongoing process where successful urban colonizers usually obtain large fitness benefits. Mechanisms proposed to explain associations between urbanization and lifehistory traits are based on behavioral flexibility in food and habitat use and reduced fear responses. We test the novel hypothesis that interspecific competition for proximity to humans is driving ur- banization. We recorded the distance during the breeding season to human habitation for 50 pairs of closely related bird species, where one was closely associated with humans while the other species was not. The degree of urbanization was larger as was range size and abundance in the species more closely associated to humans. Flight initiation distance was shorter, and species closely associated with humans were more abundant in ancestral rural habitats. Likewise, species more closely associated with humans reproduced earlier and during longer periods. These results are consistent with the hypothesis that urbanization is promoted by interspecific competition. Resulting isolation by urban habitat may further facilitate contemporary adaptation to urban environments.

关键词： birds distance to human habitation isolation by habitat isolation by time mechanisms.

CFD Analysis of an 800 kV HVDC Transformer Using Rapeseed Oil as the Cooling Fluid

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CSEE Journal of Power and Energy Systems 2022年第5期8卷 1508-1518页

作者： Edgardy M.Gutierrez diaz Gaosheng Wei Liu Cui Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China Department of Power Engineering School of Electrical EngineeringBicentenary University of AraguaTurmero 2115Venezuela

This study aims to analyze rapeseed oil’s effectiveness as a coolant of a high-voltage direct current(HVDC)converter transformer while comparing it with mineral *** employed a numerical model,assisted by Computational Fluid Dynamics(CFD)tools,to simulate the convective heat transfer inside a HVDC converter transformer,which is an oil-directed air forced(ODAF)*** model seeks to obtain the temperature and velocity fields at the critical points of the fluid *** simulation domain reproduces a 2D cross-sectional model in the center of the *** results show that rapeseed oil requires more time to gain heat from the core and windings due to its lower thermal ***,the average temperature of rapeseed and mineral oils will not significantly differ once the channel temperature reaches a stable *** indicates that the rapeseed oil can effectively replace mineral oil under the same heating ***,a slower flow of the rapeseed oil allows the fluid to smoothly enter the cooling ***,the rapeseed oil cools these channels by pushing the fluid in them and absorbs heat from the sources earlier than mineral *** improvement in cooling indicates that rapeseed oil is better than mineral oil as a coolant and electrical insulating fluid for power transformers.

关键词： CFD analysis cooling fluid HVDC transformer rapeseed oil