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Gene expression changes in spleens of the wildlife reservoir species,Eurasian wild boar(Sus scrofa),naturally infected with Brucella suis biovar 2

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Journal of Genetics and Genomics 2010年第11期37卷 725-736页

作者： Ruth C.Galindo Pilar M.Muoz María J.de Miguel Clara M.Marin Javier labairu Miguel Revilla José M.Blasco Christian Gortazar José de la Fuente Instituto de Investigación en Recursos Cinegéticos IREC(CSIC-UCLM-JCCM) Unidad de Sanidad Animal Centro de Investigación y Tecnología Agroalimentaria(CITA) ITG Ganadero Avda. Serapio Huici 2231610 VillabaNavarraSpain Departamento de Patología Animal Facultad de VeterinariaUniversity of Zaragoza Department of Veterinary Pathobiology Center for Veterinary Health SciencesOklahoma State University

Brucella suis is responsible for swine brucellosis worldwide. Of the five different B. suis biovars （by.）, bv. 2 appears restricted to Europe where it is frequently isolated from wild boar and hares, can infect pigs and can cause human brucellosis. In this study, the differ- ential gene expression profile was characterized in spleens of Eurasian wild boar naturally infected with B. suis bv. 2. Of the 20,201 genes analyzed in the microarray, 633 and 1,373 were significantly （fold change 〉 1.8; P 〈 0.01） upregulated and downregulated, respectively, in infected wild boar. The analysis was focused on genes that were over represented after conditional test for biological process gene ontology. Upregulated genes suggested that B. suis bv. 2 infection induced cell maturation, migration and/or proliferation in infected animals. The genes downregulated in infected wild boar impaired the activity of several important cellular metabolic pathways such as metabolism, cytoskeleton organization and biogenesis, immune response and lysosomal function and vesicle-mediated transport. In addition, the response to stress, sperm fertility, muscle development and apoptosis seemed to be also impaired in infected animals. These results suggested that B. suis bv. 2 may use strategies similar to other smooth brucellae to facilitate intracellular multiplication and the development of chronic infections. To our knowledge, this is the first report of the analysis of gene expression profile in hosts infected with B. suis bv. 2, which is important to understand the molecular mechanisms at the host-pathogen interface in the main reservoir species with possible implications in the zoonotic cycle of the pathogen.

关键词： Brucella suis boar genomics microarray systems biology

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Nanoparticles embedded into glass matrices:glass nanocomposites

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Frontiers of Materials Science 2022年第3期16卷 1-81页

作者： javier FONSECA Department of Chemical Engineering Northeastern UniversityBoston 02115USA

Research on glass nanocomposites(GNCs)has been very active in the past decades.GNCs have attracted—and still do—great interest in the fields of optoelectronics,photonics,sensing,electrochemistry,catalysis,biomedicine,and art.In this review,the potential applications of GNCs in these fields are briefly described to show the reader the possibilities of these materials.The most important synthesis methods of GNCs(melt-quenching,sol-gel,ion implantation,ion-exchange,staining process,spark plasma sintering,radio frequency sputtering,spray pyrolysis,and chemical vapor deposition techniques)are extensively explained.The major aim of this review is to systematize our knowledge about the synthesis of GNCs and to explore the mechanisms of formation and growth of NPs within glass matrices.The size-controlled preparation of NPs within glass matrices,which remains a challenge,is essential for advanced applications.Therefore,a thorough understanding of GNC synthesis techniques is expected to facilitate the preparation of innovative GNCs.

关键词： glass nanocomposites melt-quenching sol-gel ion implantation ion-exchange

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Nonlinear criterion for strength mobilization in brittle failure of rock and its extension to the tunnel scale

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International Journal of Mining Science and Technology 2022年第4期32卷 685-705页

作者： Rodolfo Cabezas javier Vallejos Faculty of Engineering and Technology Universidad San SebastianSantiagoChile Advanced Mining Technology Center Universidad de ChileSantiagoChile Department of Mining Engineering Universidad de ChileSantiagoChile

As underground excavations are getting deeper and field stresses increase, the behavior of intact rock blocks plays an increasingly important role in understanding and estimating the overall rock mass strength. To model the brittle behavior of intact rock blocks, the stress–strain curve is usually idealized considering a linear strength mobilization approach(cohesion-weakening-friction-strengthening, CWFS),however, it is well recognized that rock presents a nonlinear behavior in terms of the confining stress.This study extends the strength mobilization in brittle failure of rock using nonlinear criteria. To determine the model parameters, a standard statistical method that uses the complete laboratory stress–strain curves of the intact rock is employed. Several hypotheses of linear and nonlinear models are statistically compared for different types of rock and confining stress levels. Results demonstrate that the best approach to model the brittle failure of rock is to consider a nonlinear strength envelope, such as the Hoek-Brown criterion assuming a residual uniaxial compressive strength different from zero and a mi parameter that increases, both with simultaneous mobilization. This model helps to recreate highconfining conditions and a more realistic transition between peak and post-peak strength. The obtained parameters are discussed and compared with literature values to verify the validity and to develop guidelines for the estimation of parameters, providing an objective mobilization criterion. Finally, the nonlinear model was applied to a finite element code and extended to a tunnel scale in the brittle rock under high-stress conditions. A reasonable fit between the simulations and the in-situ overbreak measurements was found.

关键词： Nonlinear strength Strength mobilization Brittle failure Intact rock Scaling

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Sex and habitat differences in size and coloration of an amphibian’s poison glands match differential predator pressures

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Integrative Zoology 2022年第5期17卷 764-776页

作者： Francisco javier ZAMORA-CAMACHO Department of Phisical Chemical and Natural SystemsPablo de Olavide UniversitySevilleSpain Department of Biodiversity Ecology and EvolutionComplutense University of MadridMadridSpain

Chemical defenses are frequently accompanied by salient color patterns actively avoided by predators,a phe-nomenon referred to as aposematism.However,the production of both chemical defenses and pigments is costly,and is thus expected to be reduced under mild predator pressure.In this work,I compared the size and coloration of parotoid glands(2 dorsal,external swollen structures that secrete toxins in toads)of male and female Epidalea calamita toads from agrosystems and from pine groves.I also quantiﬁed the predator attacks received by plas-ticine toad models,whose“parotoid glands”differed in size and color conspicuousness,exposed in each habitat.Predators avoided models with large and conspicuous parotoid glands,but models in agrosystems were more of-ten attacked.Concerning actual toads,agrosystem and male individuals had larger parotoid glands,presumably implying greater production of chemical defenses than in pine grove and female conspeciﬁcs.Theseﬁndings are aligned with previous research suggesting that both agrosystem toads and males in this system are subjected to a more intense predator pressure.Difference between parotoid gland and dorsum coloration was greater in agrosys-tem toads.A marked internal pattern could function as an aposematic signal,which could counteract increased predator pressure.

关键词： anuran agrosystem aposematism Epidalea calamita plasticine model

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See how atoms dance

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National Science Review 2020年第5期7卷 833-834页

作者： javier Aizpurua Center for Materials Physics (CSIC-UPV/EHU) DIPC

As for any other wave, classical light was often thought to be constrained by the diffraction limit. However, since the pioneering works in near-field microscopy,in which the evanescent components of light localized a... 详细信息

关键词： See how atoms dance

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Moult intensity constraints along the complete moult sequence of the House Sparrow(Passer domesticus)

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Avian Research 2023年第3期14卷 394-404页

作者： Santi Guallar javier Quesada Departament de Vertebrats Museu de Ciencies Naturals de BarcelonaBarcelona08003CataloniaSpain

Sequence and intensity are two essential components of bird moult.While the moult sequences of remex tracts are highly homogenous across passerines,other tracts apparently show a high variability.Moreover,order of moult activation among tracts are insufficiently known.Likewise,dynamics of moult intensity as moult progresses remains poorly known.Here,we provide detailed quantitative description of moult sequence and intensity in the House Sparrow(Passer domesticus).To understand their role,we tested two hypotheses on the:1) protection function of moult sequence,and 2) aerodynamic and physiological constraints on moult intensity.We scored percentage growth of 313 captured sparrows using the mass of the feathers of each tract(also length for remiges)to monitor moult intensity throughout the complete moult progress,which is defined as the fraction of new and growing feathers in a moulting bird relative to the total plumage.Moult sequence was highly variable both within wing coverts and among feather tracts,with moult sequence differing among all birds to some degree.We only found support for the protection function between greater coverts and both tertials and secondaries.Remex-moult intensity conformed to theoretical predictions,therefore lending support to the aerodynamic-constraint hypothesis.Furthermore,remex-moult speed plateaued during the central stages of moult progress.However,overall plumage-moult speed did not fit predictions of the physiological-constraint hypothesis,showing that the remex moult is only constrained by aerodynamics.Our results indicate that aerodynamic loss is not simply the inevitable effect of moult,but that moult is finely regulated to reduce aerodynamic loss.We propose that the moult of the House Sparrow is controlled through sequence and intensity adjustments in order to:1) avoid body and wing growth peaks;2) fulfil the protection function between some key feather tracts;3) reduce detrimental effects on flight ability;4) keep remex sequence fixed;and 5) relax remex replacement to last

关键词： Functional constraints Local polynomial regression Passerine moult Physiological constraints Raggedness

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Taxonomy-based differences in feeding guilds of fish

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Current Zoology 2020年第1期66卷 51-56页

作者： javier SANCHEZ-HERNANDEZ Departamento de Zooloxla Xenetica e Antropoloxfa FlsicaFacultade de BioloxfaUniversidade de Santiago de CompostelaCampus Vida s/nSantiago de CompostelaEspana

It has been taken for granted that feeding guilds and behavior in animals are linked to the taxonomic relatedness of species,but empirical evidence supporting such relationship is virtually missing.To examine the importance of taxonomy on trophic ecology,I here present the first well-resolved dietary taxonomy analysis based on feeding guilds(predation,herbivory,and filtering)among families and genera within the fish order Perciformes.Taxonomic relatedness in feeding did not vary with ecosystem dimension(marine vs.freshwater).Although predation dominates among Perciformes fishes,this study shows that in most cases taxonomic units(family or genus)are composed by species with several feeding guilds.Related species are more similar in feeding compared with species that are taxonomically more distant demonstrating that there is a greater variation of feeding guilds within families than genera.Thus,there is no consistency in feeding guilds between family-and genus-level taxonomy.This study provides empirical support for the notion that genera are more informative than families,underlining that family-level taxonomy should be avoided to infer feeding habits of fish species at finer taxonomic resolution.Thus,the choice of taxonomic resolution(family or genus level)in ecological studies is key to avoid information loss and misleading results.I conclude that high-rank taxonomic units(i.e.,above the generic level)are not appropriate to test research hypotheses about the feeding of fish.

关键词： aquatic systems clades FishBase global datasets taxonomic sufficiency trophic ecology

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Meteorological indicators of dengue epidemics in non-endemic Northwest Argentina

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Infectious Disease Modelling 2022年第4期7卷 823-834页

作者： javier Armando Gutierrez Karina Laneri Juan Pablo Aparicio Gustavo javier Sibona Departamento de Física-FCE-Universidad Nacional de Salta SaltaArgentina Grupo de Física Estadística e Interdisciplinaria CONICETCentro Atòmico Bariloche-CNEASan Carlos de BarilocheRío NegroArgentina Instituto de Investigaciones en Energía no Convencional(INENCO)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)-Universidad Nacional de Salta Av.Bolivia 51004400SaltaArgentina Simon A.Levin Mathematical Computational and Modeling Sciences Center Arizona State UniversityPO Box 871904TempeAZ85287-1904USA IFEG-CONICET and Fa.M.A.F.-Universidad Nacional de Cordoba CordobaArgentina

In the last two decades dengue cases increased significantly throughout the world,giving place to more frequent outbreaks in Latin America.In the non-endemic city of San Ramòn de la Nueva Orán,located in Northwest Argentina,large dengue outbreaks alternate with several years of smaller ones.This pattern,as well as the understanding of the underlying mechanisms,could be essential to design proper strategies to reduce epidemic size.We develop a stochastic model that includes climate variables,social structure,and mobility between a non-endemic city and an endemic area.Climatic variables were input of a mosquito population ecological model,which in turn was coupled to a meta-population,spatially explicit,epidemiological model.Human mobility was included into the model given the high border crossing to the northern country of Bolivia,where dengue transmission is sustained during the whole year.We tested different hypotheses regarding people mobility as well as climate variability by fitting numerical simulations to weekly clinical data reported from 2009 to 2016.After assessing the number of imported cases that triggered the observed outbreaks,our model allows to explain the observed epidemic pattern.We found that the number of vectors per host and the effective reproductive number are proxies for large epidemics.Both proxies are related with climate variability such as rainfall and temperature,opening the possibility to test these meteorological variables for forecast purposes.

关键词： Mathematical modelling Dengue Outbreak Mosquitoes population

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Online risk‑based portfolio allocation on subsets of crypto assets applying a prototype‑based clustering algorithm

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Financial Innovation 2023年第1期9卷 797-836页

作者： Luis Lorenzo javier Arroyo Faculty of Statistic Studies Complutense UniversityAvda.Puerta de Hierros/n28040 MadridSpain

Mean-variance portfolio optimization models are sensitive to uncertainty in risk-return estimates,which may result in poor out-of-sample performance.In particular,the estimates may suffer when the number of assets considered is high and the length of the return time series is not sufficiently long.This is precisely the case in the cryptocur-rency market,where there are hundreds of crypto assets that have been traded for a few years.We propose enhancing the mean-variance(MV)model with a pre-selection stage that uses a prototype-based clustering algorithm to reduce the number of crypto assets considered at each investment period.In the pre-selection stage,we run a prototype-based clustering algorithm where the assets are described by variables representing the profit-risk duality.The prototypes of the clustering partition are auto-matically examined and the one that best suits our risk-aversion preference is selected.We then run the MV portfolio optimization with the crypto assets of the selected cluster.The proposed approach is tested for a period of 17 months in the whole cryp-tocurrency market and two selections of the cryptocurrencies with the higher market capitalization(175 and 250 cryptos).We compare the results against three methods applied to the whole market:classic MV,risk parity,and hierarchical risk parity methods.We also compare our results with those from investing in the market index CCI30.The simulation results generally favor our proposal in terms of profit and risk-profit financial indicators.This result reaffirms the convenience of using machine learning methods to guide financial investments in complex and highly-volatile environments such as the cryptocurrency market.

关键词： Fintech Mean-variance Cryptocurrency Electronic market Portfolio allocation model Clustering

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Lessons from glaucoma: rethinking the fluid-brain barriers in common neurodegenerative disorders

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Neural Regeneration Research 2019年第6期14卷 962-966页

作者： Francisco javier Carreras Department of Surgery Faculty of MedicineUniversity of Granada

Glaucoma has been recently characterized as a member of the group of anoikis-related diseases. Anoikis, a form of apoptosis, can be triggered by the unfastening of adherent junctions present in astrocytes. In those areas of the central nervous system in which the soma of the neurons or their axons and dendrites are metabolically dependent on the activity of astrocytes, a derangement of the lactate shuttle caused by a separation between the plasma membranes of neurons and astrocytes would result in metabolic impairment of the neurons themselves. In glaucoma, the triggering event has been attributed to the posterior deviation of aqueous humor towards the astrocyte-rich prelaminar tissue of the optic nerve head. The mean calcium content in the aqueous is able to interfere with calcium-dependent adherent junctions and induce anoikis of the astrocytes. As the cerebrospinal fluid has a similar base calcium concentration, a shunt of cerebrospinal fluid through the cerebral parenchyma would be able to interfere in the astrocytic architecture with dire consequences to the metabolically dependent neurons. Here the similitude between glaucoma,amyotrophic lateral sclerosis and Alzheimer's disease are discussed and the concept of the break in the fluid-brain barrier, as an event separated from the blood-brain barrier, is stressed.

关键词： fluid-brain barriers blood-brain barrier cerebrospinal fluid aqueous humor calcium ion glaucoma amyotrophic lateral sclerosis Alzheimer’s disease

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