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New injectable two-step forming hydrogel for delivery of bioactive substances in tissue regeneration

Regenerative Biomaterials 2019年第3期6卷 149-162页

作者： Edgar Pe´rez-Herrero Patricia garcı´a-garcı´a Jaime Go´mez-Morales Matias Llabre´s Araceli Delgado carmen E´vora Department of chemical Engineering and Pharmaceutical Technology University of La LagunaLa Laguna 38200TenerifeSpain Institute of Biomedical Technologies(ITB) Center for Biomedical Research of the Canary Islands(CIBICAN)University of La LagunaLa Laguna 38071TenerifeSpain Laboratory of crystallographic Studies Andalusian Earth Sciences InstituteSpanish Research Council—University of GranadaArmillaGranada 18100Spain Institute of Tropical Diseases and Healthcare of the canary Islands University of La LagunaLa Laguna 38203TenerifeSpain

A hydrogel based on chitosan,collagen,hydroxypropyl-c-cyclodextrin and polyethylene glycol was developed and *** incorporation of nano-hydroxyapatite and pre-encapsulated hydrophobic/hydrophilic model drugs diminished the porosity of hydrogel from 81.6262.25%to 69.9863.07%.Interactions between components of hydrogel,demonstrated by FTIR spectroscopy and rheology,generated a network that was able to trap bioactive components and delay the burst *** thixotropic behavior of hydrogel provided adaptability to facilitate its implantation in a minimally invasive *** profiles from microspheres included or not in hydrogel revealed a two-phase behavior with a burst-and a controlled-release *** same release rate for microspheres included or not in the hydrogel in the controlled-release period demonstrated that mass transfer process was controlled by internal *** diffusion coefficients,Deff,that describe internal diffusion inside microspheres,and mass transfer coefficients,h,*** contribution of hydrogel to mass transfer,were determined using‘genetic algorithms’,obtaining values between 2.64·10^(-15) and 6.67·10^(-15)m^(2)/s for Deff and 8.50·10^(-10) to 3.04·10^(-9) m/s for *** proposed model fits experimental data,obtaining an R2-value ranged between 95.41 and 98.87%.In vitro culture of mesenchymal stem cells in hydrogel showed no manifestations of intolerance or toxicity,observing an intense proliferation of the cells after 7 days,being most of the scaffold surface occupied by living cells.

关键词： hydrogel collagen–cyclodextrin–chitosan rheology mass transfer estradiol FITc-dextran

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Analysis of the hydrological safety of dams combining two numerical tools:Iber and DualSPHysics

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Journal of Hydrodynamics 2018年第1期30卷 87-94页

作者： J.González-cao O.garcía-Feal J.M.Domínguez A.J.c.crespo M.Gómez-Gesteira Environmental Physics Laboratory (EPHYSLAB) Universidade de Vigo Campus AsLagoas

The upgrade of the hydrological safety of dams is a critical issue to avoid failures that can dramatically affect people and assets. This paper shows a numerical methodology to analyse the safety of the Belesar dam（NW, Spain） based on two different numerical codes. First, a mesh-based code named Iber, suited to deal with large 2-D domains, is used to simulate the impoundment. The initial conditions and the inlet provided to Iber correspond to the maximum water elevation and the maximum expected inflow to the impoundment defined in the technical specifications of the dam, which are associated to the more hazardous operation conditions of the dam. Iber provides information about the time needed for water to attain the crest of the dam when floodgates are closed. In addition, it also provides the velocity of discharge when gates are opened. Then, a mesh-free code named DualSPHysics, which is especially suited to deal with complex and violent 3-D flows, is used to reproduce the behaviour of one of the spillways of the dam starting from the results obtained with Iber, which are used as inlet conditions for DualSPHysics. The combined results of both model show that the left spillway can discharge the surplus of water associated to the maximum inflow to the reservoir if the gates of the spillways are opened before the overtopping of the dam was observed. In addition, water depth measured on the spillway is considerably lower than the lateral walls, preventing overtopping. Finally, velocities at different points of the spillway showed to be in good agreement with theoretical values.

关键词： Hydrological safety dam numerical simulation Iber DualSPHysics

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Enhancing survival, engraftment, and osteogenic potential of mesenchymal stem cells

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World Journal of Stem cells 2019年第10期11卷 748-763页

作者： Daniel garcía-Sánchez Darío Fernández Joséc Rodríguez-Rey Flor M Pérez-campo Department of Molecular Biology Faculty of MedicineUniversity of CantabriaCantabria 39011Spain Laboratorio de Biología celular y Molecular Facultad de OdontologíaUniversidad Nacional del NordesteCorrientes W3400Argentina consejo Nacional de Investigaciones científicas y Técnicas Ciudad de CorrientesCorrientes W3400Argentina

Mesenchymal stem cells(MScs)are promising candidates for bone regeneration therapies due to their plasticity and easiness of ***-based treatments are generally considered a safe procedure,however,the long-term results obtained up to now are far from *** main causes of these therapeutic limitations are inefficient homing,engraftment,and osteogenic *** studies have proposed modifications to improve MSc engraftment and osteogenic differentiation of the transplanted *** strategies are aimed to improve cell resistance to the hostile microenvironment found in the recipient tissue and increase cell survival after *** strategies could range from a simple modification of the culture conditions,known as cell-preconditioning,to the genetic modification of the cells to avoid cellular *** efforts have also been done in order to enhance the osteogenic potential of the transplanted cells and induce bone formation,mainly by the use of bioactive or biomimetic scaffolds,although alternative approaches will also be *** review aims to summarize several of the most recent approaches,providing an up-to-date view of the main developments in MScbased regenerative techniques.

关键词： Mesenchymal stem cells Bone regeneration Hypoxia Anoikis Preconditioning Bioactive scaffolds Senescence Engraftment Homing Osteogenesis

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Utilizing neural networks to supplant chemical kinetics tabulation through mass conservation and weighting of species depletion

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Energy and AI 2024年第2期16卷 101-110页

作者： Franz M.Rohrhofer Stefan Posch clemens Gößnitzer JoséM.garcía-Oliver Bernhard c.Geiger Know-center GmbH Sandgasse 36Graz8010StyriaAustria LEc GmbH Inffeldgasse 19Graz8010StyriaAustria Universitat Politècnica de València Camíde VeraValència46022ValènciaSpain

Artificial Neural Networks(ANNs)have emerged as a powerful tool in combustion simulations to replace memory-intensive tabulation of integrated chemical *** reaction mechanisms,however,present a challenge for standard ANN approaches as modeling multiple species typically suffers from inaccurate predictions on minor *** paper presents a novel ANN approach which can be applied on complex reaction mechanisms in tabular data form,and only involves training a single ANN for a complete reaction *** approach incorporates a network architecture that automatically conserves mass and employs a particular loss weighting based on species *** modifications are used to improve the overall ANN performance and individual prediction accuracies,especially for minor species mass *** validate its effectiveness,the approach is compared to standard ANNs in terms of performance and ANN *** distinct reaction mechanisms(H_(2),c_(7)H_(16),c_(12)H_(26),OME_(34))are used as a test cases,and results demonstrate that considerable improvements can be achieved by applying both modifications.

关键词： Neural network approach chemical kinetics Flamelet tabulation Mass conservation Species loss weighting

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Serological surveillance for SARS-coV-2 antibodies among students,faculty and staff within a large university system during the pandemic

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World Journal of Virology 2025年第1期14卷 99-107页

作者： Marcos G Pinheiro Gabriela G O Alves Maria Eduarda R conde Sofia L costa Regina c S Sant’Anna Isa M F Antunes Mônica c carneiro Fabio S Ronzei Julia c Scaffo Felipe R Pinheiro Lialyz S Andre Helvecio c Povoa Valéria T Baltar Fabíola Giordani Eduarda S Hemerly Gisele c Alexandre Karla c de Paula Márcio Watanabe Antonio claudio L da Nóbrega Jackeline christiane P Lobato Fabio Aguiar-Alves Laboratory of Molecular Epidemiology and Biotechnology Rodolpho Albino University LaboratoryFluminense Federal UniversityNiterói 24241000Rio de JaneiroBrazil Estácio de SáUniversity Nova Friburgo 28611135Rio de JaneiroBrazil Pathology Program Medicine schoolFluminense Federal UniversityNiterói 24070090Rio de JaneiroBrazil Department of Pharmaceutical Sciences Lloyd L.Gregory School of PharmacyPalm Beach Atlantic UniversityWest Palm BeachFL 33401United States Health Institute of Nova Friburgo Fluminense Federal UniversityNova Friburgo 28613001Rio de JaneiroBrazil Department of Epidemiology and Biostatistics Institute of Collective Health(ISC)Fluminense Federal UniversityNiterói 24033900Rio de JaneiroBrazil Institute of Physical Education Fluminense Federal UniversityNiterói 24020005Rio de JaneiroBrazil Department of Statistics Fluminense Federal UniversityNiterói 24210200Rio de JaneiroBrazil Department of Physiology and Pharmacology Fluminense Federal UniversityNiterói 24210130Rio de JaneiroBrazil

BAcKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-coV-2),which led to the outbreak of coronavirus disease 2019(cOVID-19),associated with respiratory *** virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary *** tests conducted early on have helped identify how the virus is transmitted and how to curb its *** study hypothesis was that the rapid serological test for SARS-coV-2 antibodies could indicate the immunoreactive profile during the cOVID-19 pandemic in a university *** To conduct active surveillance for serological expression of anti-SARS-coV-2 antibodies in individuals within a university setting during the cOVID-19 *** This sectional study by convenience sampling was conducted in a large university in Niteroi-RJ,Brazil,from March 2021 to July *** study population consisted of students,faculty,and administrative staff employed by the university.A total of 3433 faculty members,60703 students,and 3812 administrative staff were invited to *** were gathered through rapid serological tests to detect immunoglobulin(Ig)M and IgG against ***χ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a multiple logistic regression model to evaluate *** A total of 1648 individuals were enrolled in the *** proportion of cOVID-19 positivity was 164/1648(9.8%).The adjusted logistic model indicate a positive association between the expression of IgM or IgG and age[odds ratio(OR)=1.16,95%cI:1.02-1.31](Pcontact with a cOVID-19-positive case(OR=3.49,95%cI:2.34-5.37)(Pceived the cOVID-19 vaccine(OR=2.33,95%cI:1.61-3.35)(Pcial isolation(OR=0.59,95%cI:0.41-0.84)(P<0.004).The likelihood of sho

关键词： Serological surveillance SARS-coV-2 antibodies cOVID-19 Serological rapid test Risk factors for cOVID-19

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Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells

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Journal of Integrative Plant Biology 2017年第7期59卷 475-495页

作者： María de castro Romina Martínez-Rubio José L.Acebes Antonio Encina Stephen c.Fry Penélope garcía-Angulo área de Fisiología Vegetal.Dpto.Ingenieríay ciencias Agrarias.Facultad de Biologíay ciencias Ambientales.Universidad de León The Edinburgh cell Wall Group Institute of Molecular Plant Sciences School of Biological Sciences Daniel Rutherford BuildingThe King's Buildings

As a consequence of the habituation to low levels of dichlobenil （DcB）, cultured maize cells presented an altered hemicellulose cell fate with a lower proportion of strongly wall-bound hemicelluloses and an increase in soluble extracellular polymers released into the culture medium. The aim of this study was to investigate the relative molecular mass distributions of polysaccharides as well as phenolic metabolism in cells habituated to low levels of DcB （1.5 μM）. Generally, cell wall bound hemicelluloses and sloughed polymers from habituated cells were more homogeneously sized and had a lower weight-average relative molecular mass. In addition, polysaccharides underwent massive cross-linking after being secreted into the cell wall, but this cross-linking was less pronounced in habituated cells than in non-habituated ones. However, when relativized, ferulic acid and p-coumaric acid contents were higher in this habituated cell line. Feasibly, cells habituated to low levels of DcB synthesized molecules with a lower weight-average relative molecular mass, although cross-linked, as a part of their strategy to compensate for the lack of cellulose.

关键词： Phenolic metabolism and molecular mass distribution of polysaccharides in cellulose-deficient maize cells were for

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Effect of Zn binding to phytate and humic substances on its uptake by wheat(Triticum durum L.)as affected by carbonates and Fe oxides

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Pedosphere 2022年第6期32卷 823-832页

作者： Ana M.garcÍA-LÓPEZ Ramiro REcENA Antonio DELGADO Department of Agronomy ETSIAUniversity of SevilleSeville 41013(Spain)

Although complexation with soil organic matter may improve zinc(Zn)bioavailability to plants,the effect of Zn sorbent surface on the use of complexed Zn by plants remains *** objective of this research was to elucidate how Zn complexation with humic substances(HS)and phytate affects the uptake of Zn by wheat plants depending on the main sorbent surface in growth media,i.e.,carbonates and Fe *** this end,two pot experiments were performed,one using Fe oxide-coated siliceous as the siliceous growth medium sand and the other using a mixture of calcareous sand and siliceous sand as the calcareous growth *** experiment involved three Zn sources,Zn-HS complex,Zn phytate,and ZnSO_(4).All sources were applied with surface irrigation at two Zn rates(0.25 and 2 mg kg^(-1) growth medium).The Zn-HS complex significantly increased Zn uptake by plants in both media,relative to the other two Zn sources,but no significant difference was observed between Zn phytate and ZnSO_(4).In the calcareous medium,Zn-HS complex and Zn phytate resulted in significantly higher dry biomass yields of wheat than ZnSO_(4).In the siliceous medium,spike and shoot dry biomass yields with Zn-HS complex at the low rate and Zn phytate at both rates were not significantly different from those with ZnSO_(4) at the high *** harvest,approximately 50%of the Zn applied as Zn-HS complex remained extractable by diethylenetriaminepentaacetic acid(DTPA),while this proportion was less than 20%for the other Zn ***,Zn-HS complex and Zn phytate are sources of available Zn for plants,and they are more effective than ZnSO_(4) in increasing plant growth,particularly when carbonates are the main Zn sorbent surface.

关键词： calcareous growth medium micronutrient organic matter organic phosphorus Zn availability Zn deficiency Zn sorbent surface Zn source

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True grit: ingestion of small stone particles by hummingbirds in West Mexico

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Avian Research 2021年第4期12卷 739-749页

作者： Omar Maya-garcía Mauricio Ortega-Flores Jorge E.Schondube Posgrado en ciencias Biológicas Unidad de PosgradoCoordinación del Posgrado en Ciencias BiológicasUniversidad Nacional Autónoma de MéxicoEdificio D1er pisoCircuito de PosgradosCiudad UniversitariaDel.CoyoacánC.P.04510 México D.F.Mexico Laboratorio de Ecología Funcional Instituto de Investigaciones en Ecosistemas y SustentabilidadUniversidad Nacional Autónoma de MéxicoAntigua Carretera a Pátzcuaro No.8701Col.Ex Hacienda de San Joséde la HuertaC.P.58190 MoreliaMichoacánMexico

Background: Grit is used by birds mainly for grinding hard food items but can also serve a nutritional role as a source of minerals. Ingestion of grit by birds has been documented primarily in species that feed on seeds and *** feeding mainly on nectar and small arthropods, hummingbirds also ingest grit, but why they do so is unclear. We quantified the number of grit particles in the stomachs of six species of hummingbirds during an annual cycle in a seasonal ecosystem of West ***: We compared the number of grit particles in the stomachs of different hummingbird species(Mexican Violetear colibri thalassinus, Amethyst-throated Mountaingem Lampornis amethystinus, White-eared Hummingbird Basilinna leucotis, Rivoli's Hummingbird Eugenes fulgens, Broad-tailed Hummingbird Selasphorus platycercus, and Rufous Hummingbird S. rufus), and between sex and age categories during the different seasons of a year. To deter-mine if grit was used to grind ingested arthropods, we examined the relationships between the number of grit parti-cles, the biomass of arthropods ingested, and their chitin ***: Although species did not differ in the number of grit particles in their stomachs, we found that grit was mostly ingested by female individuals, with only one male of one species(Mexican Violetear) presenting grit in its stomach. We also found that female hummingbirds had grit in their stomachs during the rainy and the cold-dry season(June-February) but not during the warm-dry season(March-May). Our analyses revealed no relationship between the number of grit particles and the amount of ingested arthropods and arthropod chitin content. However,high grit consumption was related to wasp ingestion on Mexican ***: Our results indicate that grit is used mainly by female hummingbirds. The seasonal variation in the ingestion of grit by female individuals suggests that it can be used to meet mineral requirements related to breed-ing;how

关键词： Arthropod chitin content Arthropod digestion Breeding season Mineral nutritional requirements

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Elastic Smart contracts in Blockchains

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IEEE/cAA Journal of Automatica Sinica 2021年第12期8卷 1901-1912页

作者： Schahram Dustdar Pablo Fernández JoséMaría garcía Antonio Ruiz-cortés Distributed Systems Group Vienna University of TechnologyWien 1040Austria Smart computer Systems Research and Engineering Lab Research Institute of Computer EngineeringUniversity of SevillaSevilla 41012Spain

In this paper,we deal with questions related to blockchains in complex Internet of Things(IoT)-based *** ecosystems are typically composed of IoT devices,edge devices,cloud computing software services,as well as people,who are decision makers in scenarios such as smart *** decisions related to analytics can be based on data coming from IoT sensors,software services,and ***,they are typically based on different levels of abstraction and *** poses a number of challenges when multiple blockchains are used together with smart *** work proposes to apply our concept of elasticity to smart contracts and thereby enabling analytics in and between multiple blockchains in the context of *** propose a reference architecture for Elastic Smart contracts and evaluate the approach in a smart city scenario,discussing the benefits in terms of performance and self-adaptability of our solution.

关键词： Blockchain elasticity Internet of Things(IoT) smart cities smart contracts virtual chains

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conversion of Andean montane forest to exotic forest plantation modifies soil physicochemical properties in the buffer zone of Ecuador's Podocarpus National Park

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Forest Ecosystems 2022年第6期9卷 802-812页

作者： Vinicio carrion-Paladines Angel Benítez Roberto garcía-Ruíz Departamento de ciencias Biologicas y Agropecuarias Universidad Tecnica Particular de LojaSan Cayetano Alto s/nC.P.1101608LojaEcuador Departamento de Biología Animal Biología Vegetal y EcologíaSeccion de EcologíaUniversidad de JaenCampus Las LagunillasEdificio Ciencias Experimentales y de la Salud(B3)23071JaenSpain

Background:Andean montane forests(AMF)are biodiversity hotspots that provide fundamental hydrological services as well as carbon storage and *** recent decades,southern Ecuador AMFs have been seriously threatened by increased logging and conversion to forest plantations with exotic *** this context,our main objective was to evaluate the effects of AMF conversion to forest plantations on soil physicochemical properties in the buffer zone(Bz)of the Podocarpus National Park(PNP),in southern *** this purpose,random samples were taken at a depth of 0-10 cm in four plots in each contrast zone and analyzed for bulk density,porosity,textural class,leaf litter depth,soil pH,as well as the contents of organic matter(SOM),soil organic carbon(SOc),total nitrogen,and available phosphorus and ***:The results indicate that the conversion of AMFs produces an increase in bulk density and a decrease in SOM,SOc,and total nitrogen contents,thus modifying soil properties,which could result in a decrease in water regulation capacity and produce an increased risk of soil *** accelerates degradation processes,as well as threatens shortages of the drinking water ***:This study can help decision-makers to implement soil management plans in the Bz of the PNP,based on the implementation of new regulations,where the conservation of AMF is *** addition,it is recommended to apply environmental restoration strategies in the anthropized areas of the AMF,as well as in the areas with exotic eucalyptus and pine plantations.

关键词： Andean montane forests Land use conversion Edaphic properties

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