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Journal of Mountain Science 2016年第7期13卷 1139-1153页

作者： José Antonio LópEZ-SáEZ Francisca ALBA-SánCHEZ Sandra ROBLES-LópEZ sebastián pérez-díaz daniel ABEL-SCHAAd Silvia SABARIEGO-RUIZ Arthur GLAIS Research Group Archaeobiology Institute of History CSIC dept.Botany Faculty of Sciences University of Granada dept.of plant Biology Faculty of Biology Complutense University LETG CAEn GEOpHEn-UMR 6554 CnRS University of Caen-Normandie

A high-altitude peat sequence from the heart of the Spanish Central System(Gredos range) was analysed through a multi-proxy approach to determine the sensitivity of high-mountain habitats to climate, fire and land use changes during the last seven hundred years, providing valuable insight into our understanding of the vegetation history and environmental changes in a mountain pass close to a traditional route of transhumance. The pollen data indicate that the vegetation was dominated by shrublands and grasslands with scattered pines in high-mountain areas, while in the valleys cereals, chestnut and olive trees were cultivated. Strong declines of high-mountain pines percentages are recorded at 1540, 1675, 1765, 1835 and 1925 cal Ad, which may be related to increasing grazing activities and/or the occurrence of anthropogenic fires. The practice of mountain summer farming and transhumance deeply changed and redesigned the landscape of the high altitudes in central Spain(Gredos range) since the Middle Ages, although its dynamics was influenced in some way by climate variability of the past seven centuries.

关键词： Climate and human impacts Fire Late Holocene Gredos range Vegetation history

10,000 years of climate control over carbon accumulation in an Iberian bog(southwestern Europe)

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Geoscience Frontiers 2019年第4期10卷 1521-1533页

作者： Xabier pontevedra-pombal daniel Castro Martín Souto Isabel Fraga William H. Blake Maarten Blaauw José A. López-Sáez sebastián pérez-díaz Marcos Valcárcel Eduardo García-Rodeja dpto.Edafoloxía e Química Agrícola Fac.BioloxíaUniversidade de Santiago de CompostelaGaliciaSpain dpto.Botánica Fac.BioloxíaUniversidade de Santiago de CompostelaGaliciaSpain School of Geography Earth and Environmental SciencesUniversity of PlymouthUK School of natural and Built Environment Queen’s University BelfastNorthern IrelandUK GI Arqueobiología Instituto de HistoriaCCHS - CSICMadridSpain dpto.Xeografía Fac.Xeografía e HistoriaUniversidade de Santiago de CompostelaGaliciaSpain

The northwest region of the Iberian peninsula is home to a unique ecosystem of bogs,which are particularly sensitive to projected climate cha *** this context,the rate of carbon(C)accumulation in Chao de Veiga *** intact raised bog,was *** in the accumulation rate over the past10 millennia were determined in a peat core of 847 cm in depth,with a high mean rate of peat growth(11 yr cm^-1,0.09 cm yr^-1).An age-depth model was generated from 22 14C dates and fallout ***,stratigraphical and physico-chemical data confirmed the existence of a single cycle of peat formation throughout the Holocene and the formation of ombrotrophic peat 9500 years *** total mean C content was 50.2%,and over 10 millennia 583 kg C m^-2 accumulated at a mean rate of 35.3 g C m^-2 yr^-1,with a long-term(apparent)rate of carbon accumulation in the catotelm of59.9 g C m^-2 yr^-*** values are much higher than reported for other Iberian peatlands and are amongst the highest documented for peatlands in the northern *** dynamics of C accumulation and other measured parameters reveals important variations throughout the *** could be associated with the main climatic events described in the northern hemisphere and are highly consistent with models established for northern *** Chao de Veiga Mol raised bog is unique and of great potential value for carrying out high resolution palaeoenvironmental studies,especially in relation to regional and Iocal modulations in southern Europe.

关键词： peatland Geochemistry Holocene Climate change palaeoenvironmental reconstruction

High-resolution patterns of palaeoenvironmental changes during the Little Ice Age and the Medieval Climate Anomaly in the northwestern Iberian peninsula

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Geoscience Frontiers 2020年第5期11卷 1461-1475页

作者： daniel Castro Martin Souto Maria Isabel Fraga Eduardo Garcia-Rodeja sebastian perez-diaz Jose Antonio Lopez Saez Xabier pontevedra-pombal dpto.Botanica Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain dpto.Edafoloxia e Quimica Agricola Fac.BioloxiaUniversidade de Santiago de CompostelaGaliciaSpain dpto.Geografia Urbanismo y Ordenacion Del TerritorioETS CaminosCanales y PuertosUniversidad de CantabriaSpain GI Arqueobiologia Instituto de HistoriaCCHS–CSICMadridSpain

to identify plant macrofossils,estimate peat humification and calculate hydroclimatic indices based on current bog species,with the overall aim of determining the climate conditions associated with evolution of the bog during the Medieval Climate Anomaly and the Little Ice *** proxies,together with historical and climate data,proved to be good indicators of the changes in bog surface ***:of the core led to identification of 9 different periods:two corresponding to the so-called Medieval Climate Anomaly(930 to 1345 Ad,1075–665 calibrated years before present[*** Bp]);four corresponding to the Little Ice Age(1345 to 1905 Ad;665–105 cal yr Bp);and three corresponding to the last century(1905 to 2000 Ad).The findings revealed a generally dry climate that lasted until the 14th century,followed by a transition to a long period with a more humid,but characteristically very variable climate,which ended at the beginning of the 20th century and was followed by a rapid transition to more humid conditions and finally,a change to drier *** Medieval Climate Anomaly was indicated by the abundance of dry-adapted mosses(Leucobryum glaucum,Hypnum cupressiforme)and characterized by warm dry conditions and high levels of peat humification,with alternating wet *** LIA period was dated by a large abundance of Sphagnum species(an indicator of wetness)and a gradual increase in the humification ***,four different climate phases were differentiated in this ***-resolution reconstruction of the evolution of the CVM bog and the multiproxy approach have together enabled a more detailed identification of climatic variations in this area,which are generally consistent with the global models,as well as better definition of the elusive climatic oscillations in the last millennium and confirmation of the importance of local modulation of global *** study provides new information and a detailed chronology of climatic events that will hel

关键词： Last millennium Raised bog plant macrofossil Humification analysis Southwest Europe Climate change

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

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neural Regeneration Research 2025年第3期20卷 660-670页

作者： Ernesto doncel-pérez Gabriel Guízar-Sahagún Israel Grijalva-Otero Hospital nacional de parapléjicos de Toledo Servicio de Salud de Castilla La Mancha(SESCAM)ToledoSpain Medical Research Unit for neurological diseases UMAE Hospital de EspecialidadesCentro Médico Nacional Siglo XXIIMSSCiudad de MéxicoMéxico

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoratio

关键词： neural regeneration neuroprotection spinal cord injury repair spinal cord injury treatments structural restoration of spinal cord injury

Impacts of pI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

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neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón pérez-núñez María Fernanda González Ana María Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for Chronic diseases(ACCdiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune *** phosphoinositide 3-kinase(pI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the pI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/pI3K/AKT/connexin 43,and notch/pI3K/AKT *** targeting the inactivation of the pI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the pI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(Cd90)

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

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neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz Juan d.navarro-López neurophysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in Ad,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

determination and(Re)parametrization of Rational developable Surfaces

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Journal of Systems Science & Complexity 2015年第6期28卷 1426-1439页

作者： SHEn Liyong prez-díaz Sonia School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Mathematics Mechanization Academy of Mathematics and Systems Science Chinese Academy of Sciences Key Laboratory of Big data Mining and Knowledge management Chinese Academy of Sciences dpto de Física y Matemáticas Universidad de Alcalá

The developable surface is an important surface in computer aided design, geometric modeling and industrial manufactory. It is often given in the standard parametric form, but it can also be in the implicit form which is commonly used in algebraic geometry. not all algebraic developable surfaces have rational parametrizations. In this paper, the authors focus on the rational developable surfaces. For a given algebraic surface, the authors first determine whether it is developable by geometric inspection, and then give a rational proper parametrization in the affrmative case. For a rational parametric surface, the authors also determine the developability and give a proper reparametrization for the developable surface.

关键词： parametrization proper rational developable surface reparametrization

A Symbolic-numeric Approach for parametrizing Ruled Surfaces

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Journal of Systems Science & Complexity 2020年第3期33卷 799-820页

作者： pÉrez-dÍaz Sonia SHEn Li-Yong dpto.de Física y Matemáticas Universidad de Alcalá28871-Alcaláde HenaresMadridSpain School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper presents symbolic algorithms to determine whether a given surface(implicitly or parametrically defined)is a rational ruled surface and find a proper parametrization of the ruled ***,in practical applications,one has to deal with numerical objects that are given approximately,probably because they proceed from an exact data that has been perturbed under some previous measuring process or *** these numerical objects,the authors adapt the symbolic algorithms presented by means of the use of numerical *** authors develop numeric algorithms that allow to determine ruled surfaces"close"to an input(not necessarily ruled)surface,and the distance between the input and the output surface is computed.

关键词： Implicit representation numeric algorithm ruled surface standard parametrization

Climate-driven variations in productivity reveal adaptive strategies in Iberian cork oak agroforestry systems

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Forest Ecosystems 2022年第1期9卷 83-93页

作者： José Carlos pérez-Girón Emilio Rafael díaz-Varela pedro Álvarez-Álvarez department of Organisms and Systems Biology Polytechnic School of MieresUniversity of OviedoE-33600MieresAsturiasSpain Research Group on planning and Management in Complex Adaptive Socio-Ecological Systems(COMpASSES).School of Engineering University of Santiago de CompostelaE-27002LugoSpain

Background:Cork oak agroforestry systems(AFS)have been managed for centuries by humans to produce cork and other goods and services and have recently been recognised as an important reservoir for biodiversity improvement and ***,despite having recently been included as a natural habitat of community-wide interest within the EU Habitats directive,these systems are in a critical situation of *** other factors,they are strongly threatened by climate change,the effects of which are also expected to be particularly severe in the Mediterranean *** this study,we aimed to evaluate the influence of climate variability by examining primary production indicators and also to analyse whether the geographical location may have a role in the incidence of the adverse effects of ***:Cork oak AFS were identified in the Forest Map of Spain and the Land use map of portugal and categorized on the basis of canopy *** climate data from 2001 to 2020 were used to model relationships with climate predictors and proximity to the *** analysis was conducted to identify significant spatial clusters of high-and low-efficiency ***:The responses to the influence of climatic conditions differed among the various cork oak AFS categories,particularly in the forest category,which was less dependent on climate *** humidity and water availability were the main drivers of net primary production(npp).Carbon use efficiency(CUE)was limited by relative humidity and spring temperature in open *** to the coast proved beneficial,especially in years with adverse weather conditions,but was not a limiting factor for survival of the ***,the results of the hotspot analysis supported the other findings,highlighting high-efficiency areas close to the coast and cold spots grouped in specific areas or dispersed ***:Canopy plays a key role in the influence of climatic conditions,particu

关键词： net primary production Carbon use efficiency Climate Quercus suber Agroforestry system

does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

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neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri H.Juárez Adalberto Merighi department of Veterinary Sciences University of TurinGrugliascoTOItaly department of psychiatry and neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective