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Re-folded structure of syn-orogenic granitoids(Padrón dome, NW Iberia):Assessing rheological evolution of cooling continental crust in a collisional setting

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Geoscience Frontiers 2019年第2期10卷 651-669页

作者： Rubén Díez Fernández Francisco J.Rubio Pascual Luis Miguel Martín Parra departamento de Geodinámica Estratigrafía y PaleontologíaFacultad de Ciencias GeológicasUniversidad Complutense de Madrid Instituto Geológico y Minero de Espana

This contribution discusses about the rheological, kinematic and dynamic frameworks necessary to produce recumbent and upright folds from syn-orogenic granitic massifs that were formed during an early stage of magma genesis related to the onset of a migmatitic dome. Syn-kinematic granitoids occurring within the high-grade infrastructure of the Padron migmatitic dome(NW Iberia) are deformed into largescale recumbent folds(D_2) that are later affected by upright folds(D_3). Petrostructural analysis of a selected area of this dome reveals that after a period of crustal thickening(D_1), NNW-directed extensional flow gave way to recumbent folds and penetrative axial plane foliation(S_2). Superimposed subhorizontal compression resulted in upright folds(D_3). A closer view into the dynamics of the dome allows exploring the factors that may condition the nucleation of folds with contrasting geometries during progressive deformation of molten continental crust. The formation of folds affecting syn-kinematic granitoids suggests a cooling metamorphic path in migmatitic domes. Active and passive folding mechanisms require a crystallizing(cooling) magma to nucleate folds. A more competent metamorphic host inhibits fold nucleation from much less competent magmas. As it crystallizes, magma becomes more rigid(competent),and approaches viscosity values of its host. Passive folding is favored when no significant competence contrast exists between magma and host, so this folding mechanism is more likely shortly after magma genesis and emplacement. In such conditions, and under dominant subhorizontal flow accompanied by flattening(D_2),passive folding would produce isoclinal recumbent geometries. Further magma cooling introduces a shift into the rheological behavior of partially molten crust. Thereon, crystallizing magma bodies would represent significant competence contrasts relative to their host. At this point, buckling is a more likely folding mechanism, and more regular, buckle fo

关键词： Recumbent folds Migmatitic domes Partial melting Crustal-derived granitoids Orogenic collapse Variscan orogen

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quasi-in vivo corrosion behavior of AZ31B Mg alloy with hybrid MWCNTs-PEO/PCL based coatings

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Journal of Magnesium and Alloys 2022年第11期10卷 3217-3233页

作者： Morteza Daavari Masoud Atapour Marta Mohedano Hugo Mora Sánchez Juan Rodríguez-Hernández Endzhe Matykina Raul Arrabal Aboozar Taherizadeh department of Materials Engineering Isfahan University of Technology84156-83111 IsfahanIran departamento de Ingeniería química y de Materiales Facultad de Ciencias QuímicasUniversidad Complutense28040 MadridSpain Institute of Polymer Science and Technology(CSIC) Polymer Functionalization GroupMadrid 28006Spain

This study investigated the effects of multi-walled carbon nanotubes(MWCNTs) and polycaprolactone(PCL) on the quasi-in vivo corrosion behavior of AZ31B Mg alloy treated by plasma electrolytic oxidation(PEO). Thin(~2 μm, PCTPCL4) and thick(~60 μm, PCTPCL6) PCL layers were applied only onto the MWCNTs-PEO coating(PCT) as it showed better corrosion performance. Findings reveal that incorporation of MWCNTs induced several structural and functional modifications in the PEO coating, such as increased roughness, a thicker inner barrier layer, and reduced ***-in vivo corrosion testing was carried out under controlled temperature, p H, and fluid flow in simulated body fluid(SBF) by electrochemical impedance spectroscopy(EIS) and hydrogen evolution experiments. EIS results revealed that, after 48 h immersion, a diffusion process controlled hydration of the ceramic coatings. Comparison of the collected hydrogen after 15 days of immersion in the quasi-in vivo environment revealed that the PEO and PCT ceramic coatings decreased hydrogen generation by up to 74% and 91%, respectively, compared to non-coated ***6 coating exhibited the lowest amount of collected hydrogen(0.2 m L/cm^(2)). The thick PCL layer delayed the onset of substrate corrosion for at least 120 h, reducing the corrosion rate by 85% compared with the PCT.

关键词： AZ31B Mg alloy Plasma electrolyte oxidation(PEO) Multi-walled carbon nanotubes(MWCNTs) quasi-in vivo condition Polycaprolactone(PCL)

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Validation of kinetic modeling of progesterone release from polymeric membranes

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Asian Journal of Pharmaceutical Sciences 2018年第1期13卷 54-62页

作者： Analia Irma Romero Mercedes Villegas Alicia Graciela Cid Mónica Liliana Parentis Elio Emilio Gonzo José María Bermúdez Instituto de Investigaciones para la Industria química Universidad Nacional de Salta – Consejo Nacional de Investigaciones Científicas y Técnicas facultad de Ingeniería Universidad Nacional de Salta

Mathematical modeling in drug release systems is fundamental in development and optimization of these systems, since it allows to predict drug release rates and to elucidate the physical transport mechanisms involved. In this paper we validate a novel mathematical model that describes progesterone(Prg) controlled release from poly-3-hydroxybutyric acid(PHB) membranes. A statistical analysis was conducted to compare the fitting of our model with six different models and the Akaike information criterion(AIC) was used to find the equation with best-fit. A simple relation between mass and drug released rate was found,which allows predicting the effect of Prg loads on the release behavior. Our proposed model was the one with minimum AIC value, and therefore it was the one that statistically fitted better the experimental data obtained for all the Prg loads tested. Furthermore, the initial release rate was calculated and therefore, the interface mass transfer coefficient estimated and the equilibrium distribution constant of Prg between the PHB and the release medium was also determined. The results lead us to conclude that our proposed model is the one which best fits the experimental data and can be successfully used to describe Prg drug release in PHB membranes.

关键词： Mathematical models Model validation Drug delivery/release Mass transfer coefficient Equilibrium distribution constant

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Exocytosis,endocytosis and recycling of secretory vesicles in neuroendocrine cells,and its regulation by cortical actin

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BIOCELL 2022年第8期46卷 1867-1873页

作者： ANA M.CÁRdeNAS I.GALLO FERNANDO D.MARENGO Centro Interdisciplinario de Neurociencia de Valparaíso Facultad de CienciasUniversidad de ValparaísoValparaíso2360102Chile Instituto de Fisiología Biología Molecular y NeurocienciasCONICET.Departamento de Fisiología y Biología Molecular y CelularFacultad de Ciencias Exactas y Naturales Universidad de Buenos AiresBuenos Aires1428Argentina

The cortical actin network is a mesh of filaments distributed beneath the plasmalemma that dynamically reacts in response to *** dynamic network of cortical filaments,together with motor myosin partners,adjusts the plasmalemma tension,organizes membrane protein microdomains,remodels the cell surface and drives vesicle motion in order to fine-tune exocytosis,endocytosis and recycling of secretory *** this review,we discuss how these mechanisms work in secretory cells.

关键词： Cortical actin Neuroendocrine cell Chromaffin cell Exocytosis Endocytosis

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In vitro polymerization of the dopamine-borate melanin precursor:A proof-of-concept regarding^(10)boron neutron-capture therapy for melanoma

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BIOCELL 2023年第4期47卷 919-928页

作者： JUAN C.STOCKERT SILVINA A.ROMERO MARCELO N.FELIX-POZZI ALFONSO BLÁZquEZ-CASTRO Instituto de Oncología“Angel H.Roffo” Área InvestigaciónFacultad de MedicinaUniversidad de Buenos AiresBuenos AiresC1417DTBArgentina Centro Integrativo de biología y química Aplicada Universidad Bernardo O’HigginsSantiago8370854Chile departamento de Micro y Nanotecnología Instituto de Nanociencias y NanotecnologíaCentro Atómico ConstituyentesComisión Nacional de Energía AtómicaBuenos AiresCP 1650Argentina departamento de biología Universidad Autónoma de MadridMadrid28049Spain

The^(10)boron neutron-capture therapy(BNCT)is an emerging antitumoral method that shows increasing biomedical *** is based on the selective accumulation of the^(10)boron isotope within the tumor,which is then irradiated with low-energy thermal neutrons,generating nuclear fission that produces 7lithium,4helium,andγ*** catechol-borate esters have been rather overlooked as precursors of melanin biosynthesis,and therefore,a proof-of-concept approach for using dopamine-borate(DABO)as a suitable boron-containing candidate for potential BNCT is presented *** can spontaneously oxidize and autopolymerize in vitro,giving a soluble,eumelaninlike brown-black poly-DABO *** melanoma cell cultures treated with 1 mM DABO for 24 and 48 h were viable and showed no signs of damage or cell *** stability and possible trans-esterification of DABO is shortly *** calculations and quantitative structure-activity relationships(QSAR)analysis of DABO and the BNCT agent BPA indicated that they should be cell permeant and accumulate within lysosomes and *** modeling allows visualization of both the DABO precursor and the structure of a borate derivative of the proposed catechol-porphycene model for eumelanin,showing interesting features from molecular orbital *** main difference between DABO and other agents,such as BPA,is that it is not a boronic acid nor a boron *** simple catechol-borate ester(protected from oxidation and blackening)could be administrated to living cells and organisms,in which biosynthesis of boron-melanin in melanoma melanocytes can lead to improved BNCT.

关键词： ^(10)Boron Borate esters Catechols Dopamine Eumelanin Melanoma

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Epigenetic regulation of stemness maintenance in the neurogenic niches

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World Journal of Stem Cells 2015年第4期7卷 700-710页

作者： Raquel Montalbán-Loro Ana Domingo-Muelas Alexandra Bizy Sacri R Ferrón departamento de biología Celular Facultad de BiologíaUniversidad de Valencia

In the adult mouse brain, the subventricular zone lining the lateral ventricles and the subgranular zone in the dentate gyrus of the hippocampus are two zones that contain neural stem cells(NSCs) with the capacity to give rise to neurons and glia during the entire life of the animal. Spatial and temporal regulation of gene expression in the NSCs populationis established and maintained by the coordinated interaction between transcription factors and epigenetic regulators which control stem cell fate. Epigenetic mechanisms are heritable alterations in genome function that do not involve changes in DNA sequence itself but that modulate gene expression, acting as mediators between the environment and the genome. At the molecular level, those epigenetic mechanisms comprise chemical modifications of DNA such as methylation, hydroxymethylation and histone modifications needed for the maintenance of NSC identity. Genomic imprinting is another normal epigenetic process leading to parentalspecific expression of a gene, known to be implicated in the control of gene dosage in the neurogenic niches. The generation of induced pluripotent stem cells from NSCs by expression of defined transcription factors, provide key insights into fundamental principles of stem cell biology. Epigenetic modifications can also occur during reprogramming of NSCs to pluripotency and a better understanding of this process will help to elucidate the mechanisms required for stem cell maintenance. This review takes advantage of recent studies from the epigenetic field to report knowledge regarding the mechanisms of stemness maintenance of neural stem cells in the neurogenic niches.

关键词： Neurogenesis Neural stem cell Epigenetics Gene expression regulation Chromatin modifications DNA methylation

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Role of vascular endothelial growth factor as a critical neurotrophic factor for the survival and physiology of motoneurons

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Neural Regeneration Research 2023年第8期18卷 1691-1696页

作者： Paula M.Calvo Rosendo G.Hernández Rosa R.de la Cruz Angel M.Pastor departamento de Fisiología Facultad de BiologíaUniversidad de SevillaSevillaSpain

Vascular endothelial growth factor(VEGF)was discovered by its angiogenic ***,during evolution,it appeared earlier as a neurotrophic factor required for the development of the nervous system in invertebrates lacking a circulatory *** aimed at reviewing recent evidence indicating that VEGF has neuroprotective effects in neurons exposed to a variety of *** particular interest is the link established between VEGF and motoneurons,especially after the design of the VEGFδ/δmutant *** mice are characterized by low levels of VEGF and develop muscle weakness and motoneuron degeneration resembling amyotrophic lateral *** administration of VEGF through several routes to animal models of amyotrophic lateral sclerosis delays motor impairment and motoneuron degeneration and increases life *** are new recent advances in the role of VEGF in the physiology of *** experimental aims use the extraocular(abducens)motoneurons lesioned by axotomy as a model for studying VEGF *** abducens motoneurons exhibit severe alterations in their discharge activity and a loss of synaptic *** exogenous administration of VEGF to axotomized abducens motoneurons,either from the transected nerve or intraventricularly,fully restores the synaptic and discharge properties of abducens motoneurons,despite being *** addition,when an anti-VEGF neutralizing antibody is delivered from the muscle to intact,uninjured abducens motoneurons,these cells display alterations in their discharge pattern and a loss of synaptic boutons that resemble the state of *** these data indicate that VEGF is an essential neurotrophic factor for motoneurons.

关键词： abducens nucleus amyotrophic lateral sclerosis cell death extracellular single-unit recordings eye movements neurodegeneration oculomotor trophic factors

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Statistical evaluation of fluoride contamination in groundwater resources of Santiago del Estero Province, Argentina

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Geoscience Frontiers 2020年第6期11卷 2197-2205页

作者： K.Rondano Gómez C.E.López Pasquali G.Paniagua González P.Fernández Hernando R.M.Garcinuño Martínez departamento de Ciencias Básicas Facultad de Ciencias ForestalesUniversidad Nacional de Santiago Del EsteroArgentina departamento de Ciencias Analíticas Facultad de CienciasUniversidad Nacional de Educación a DistanciaSpain departamento de química Analítica Facultad de Agronomía y AgroindustriasUniversidad Nacional de Santiago Del EsteroArgentina

This study investigates the suitability of statistical techniques for evaluating the fluoride content and the groundwater quality from Robles department(RD)and Banda department(BD)in Santiago del Estero(Argentina).For the original statistical study,evaluation of nine parameters(fluoride,pH,conductivity,atmospheric and water temperature,total dissolved solids,chloride,hardness,and alkalinity)of 110 collected underground water samples from 23 dispersed rural areas was *** samples were obtained by sampling taken from wells at different *** levels were determined by a standard colorimetric method in two seasonal periods,the dry(from April to September)and rainy(from October to March)*** analytical results obtained for physicochemical parameters such as pH,total dissolved solids(TDS),and temperature does not reveal any notable difference between the rainy and dry seasons *** both seasons,the atmospheric temperature average was 22℃.With respect to fluoride content,approximately 50%of the analysed groundwater samples exceeded the limit established by current legislation(1.0 mg/L),obtaining concentration levels in the range of 0.01-2.80 mg/*** study demonstrates the usefulness of the univariate statistical method(quartiles calculation,interquartile range IQR),multivariate principal component analysis(PCA),and cluster analysis to establish a better understanding of the state of the contamination of the waters in the region studied.

关键词： Source water protection Santiago del Estero Multivariate statistical analysis Fluoride Spectrophotometry

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Magnetofection as a new tool to study microglia biology

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Neural Regeneration Research 2019年第5期14卷 767-768页

作者： Jose Luis Venero Miguel Angel Burguillos Instituto de Biomedicina de Sevilla (IBiS)/Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla and departamento de Bioquímica y biología Molecular Facultad de Farmacia Universidad de Sevilla department of Biochemistry University of Cambridge

Microglia are the resident macrophages of the brain,originally described by Pio del Rio-Hortega(a student of Santiago Ramon y Cajal)in a series of studies in *** those pioneering studies,many others have followed to describe microglia as complex and multitasking cells with many diverse roles under physiological(*** key role in synapse pruning during development)or diseased *** exist as sentinels or surveyors of the environment that surround neurons,becoming reactive upon a wide array of stimuli and consequently developing an appropriate inflammatory *** fact,a neuroinflammatory response driven by microglia is found in virtually every disease process that occurs within the central nervous ***,a better understanding of the mechanisms governing the microglia response is the key to improving the outcome of neurodegenerative conditions.

关键词： Magnetofection new tool study microglia biology

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Hyperammonemia,brain edema and blood-brain barrier alterations in prehepatic portal hypertensive rats and paracetamol intoxication

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World Journal of Gastroenterology 2004年第9期10卷 1321-1324页

作者： Camila Scorticati Juan P.Prestifilippo Francisco X.Eizayaga Salvador Romay MaríaA Fernández AbrahamLemberg Juan C.Perazzo José L.Castro Cátedra de Fisiopatología Facultad de Farmaciay BioquímicaUniversidad de Buenos AiresBuenos AiresArgentina Cátedra de Farmacología Facultad de Farmacia y BioquímicaUniversidad de Buenos AiresBuenos AiresArgentina

AIM:To study the blood-brain barrier integrity,brain edema, animal behavior and ammonia plasma levels in prehepatic portal hypertensive rats with and without acute liver intoxication. METHODS:Adults male Wistar rats were divided into four *** Ⅰ:sham operation;Ⅱ:Prehepatic portal hypertension,produced by partial portal vein ligation;Ⅲ: Acetaminophen intoxication and Ⅳ:Prehepatic portal hypertension plus *** was administered to produce acute hepatic *** pressure,liver serum enzymes and ammonia plasma levels were *** cortex water content was registered and trypan blue was utilized to study blood brain barrier *** and behavioral tests were recorded. RESULTS:Portal hypertension was significantly elevated in groups Ⅱ and Ⅳ.Uver enzymes and ammonia plasma levels were increased in groups Ⅱ,Ⅲ and Ⅳ.Prehepatic portal hypertension (group Ⅱ),acetaminophen intoxication (group Ⅲ) and both (group Ⅳ) had changes in the blood brain-barrier integrity (trypan blue) and *** edema was present in rats with acute hepatic injury in groups Ⅲ and Ⅳ.Behavioral test (rota rod) was altered in group Ⅳ. CONCLUSION:These results suggest the possibility of another pathway for cortical edema production because blood brain barrier was altered (vasogenic) and hyperammonemia was registered (oltotoxic).Group Ⅳ,with behavioral altered test,can be considered as a model for study at an early stage of portal-systemic encephalopathy.

关键词： Acetaminophen Analgesics, Non-Narcotic Animals Behavior, Animal Blood-Brain Barrier Brain Edema Humans Hyperammonemia Hypertension, Portal Liver Male Rats Rats, Wistar

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