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Developing a dynamic growth model for teak plantations in India

Forestry Studies in China 2014年第2期16卷 71-80页

作者： Vindhya Prasad Tewari juan gabriel lvarez-gonzález Oscar García Forest Biometry Division Institute of Wood Science and TechnologyBangaloreIndia Unidad de Gestión Forestal Sostenible Departamento de Ingenieria AgroforestalUniversidad de Santiago de CompostelaLugoSpain University of Northern British Columbia ColumbiaBCCanada

Background： Tectono grandis （teak） is one of the most important tropical timber species occurring naturally in India. Appropriate growth models, based on advanced modeling techniques, are not available but are necessary for the successful management of teak stands in the country. Long-term forest planning requires mathematical models and the principles of Dynamical System Theory provide a solid foundation for these. Methods： The state-space approach makes it possible to accommodate disturbances and avarying environment. In this paper, an attempt has been made to develop a dynamic growth model based on the limited data, consisting of three annual measurements, collected from 22 teak sample plots in Karnataka, Southern India. Results： A biologically consistent whole-stand growth model has been presented which uses the state-space approach for modelling rates of change of three state-variables viz., dominant height, stems per hectare and stand basal area. Moreover, the model includes a stand volume equation as an output function to estimate this variable at any point in time. Transition functions were fitted separately and simultaneously. Moreover, a continuous autoregressive error structure is also included in the modelling process. For fitting volume equation, generalized method of moments was used to get efficient parameter estimates under heteroscedastic conditions. Conclusions： A simple model containing few free parameters performed well and is particularly well suited to situations where available data is scarce.

关键词： Mortality Basal area Canopy closure Relative occupancy State-space approach Tectona grandis

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Improving precision of field inventory estimation of aboveground biomass through an alternative view on plot biomass

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Forest Ecosystems 2020年第4期7卷 760-769页

作者： Christoph Kleinn Steen Magnussen Nils Nölke Paul Magdon juan gabrielálvarez-gonzález Lutz Fehrmann César Pérez-Cruzado Forest Inventory and Remote Sensing Georg-August-Universität Göttingen37077 GöttingenGermany. Canadian Forest Service Natural Resources CanadaVictoriaBC V8Z 1M5Canada. Department of Agroforestry Engineering University of Santiago de CompostelaE-27002 LugoSpain

We contrast a new continuous approach(CA)for estimating plot-level above-ground biomass(AGB)in forest inventories with the current approach of estimating AGB exclusively from the tree-level AGB predicted for each tree in a plot,henceforth called DA(discrete approach).With the CA,the AGB in a forest is modelled as a continuous surface and the AGB estimate for a fixed-area plot is computed as the integral of the AGB surface taken over the plot *** with the CA,the portion of the biomass of in-plot trees that extends across the plot perimeter is ignored while the biomass from trees outside of the plot reaching inside the plot is *** use a sampling simulation with data from a fully mapped two hectare area to illustrate that important differences in plot-level AGB estimates can *** CA-based estimates of mean AGB should be less variable than those derived from the *** realized,this difference translates to a higher precision from field sampling,or a lower required sample *** our case study with a target precision of 5%(*** standard error of the estimated mean AGB),the CA required a 27.1%lower sample size for small plots of 100 m2 and a 10.4%lower sample size for larger plots of 1700 *** examined sampling induced errors only and did not yet consider model *** discuss practical issues in implementing the CA in field inventories and the potential in applications that model biomass with remote sensing *** CA is a variation on a plot design for above-ground forest biomass;as such it can be applied in combination with any forest inventory sampling design.

关键词： Branch biomass Foliage biomass Stem biomass Biomass surface plots Sampling surfaces Standard error of estimation

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Local and generalized height-diameter models with random parameters for mixed,uneven-aged forests in Northwestern Durango,Mexico

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Forestry Studies in China 2014年第1期16卷 41-49页

作者： Sacramento Corral-Rivas juan gabriel lvarez-gonzález Felipe Crecente-Campo José Javier Corral-Rivas Instituto Tecnológico de EI Salto Mesa del Tecnologico s/n.Apdo.Postal No.2EI Salto P.N.34950DurangoMéxico Departamento de Ingenieria Agroforestal Universidad de Santiago de Compostela.Escuela Politécnica SuperiorCampus Universitario27002 LugoEspana lnstituto de Silvicultura e Industria de la Madera Universidad Jurez del Estado de DurangoBlvd.del Guadiana # 501.Cuidad Universitaria34160 DurangoMexico

Background:We used mixed models with random components to develop height-diameter(h-d) functions for mixed,uneven-aged stands in northwestern Durango(Mexico),considering the breast height diameter(d) and stand variables as ***:The data were obtained from 44 permanent plots used to monitor stand growth under forest management in the study ***:The generalized Bertalanffy-Richards model performed better than the other generalized models in predicting the total height of the species under *** the genera Pinus and Quercus,the models were successfully calibrated by measuring the height of a subsample of three randomly selected trees close to the mean d,whereas for species of the genera Cupressus,Arbutus and Alnus,three trees were also selected,but they are specifically the maximum,minimum and mean d ***:The presented equations represent a new tool for the evaluation and management of natural forest in the region.

关键词： Conifer and broadleaves forests h-d relationship Mixed models Calibration

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Beyond wrecking a wall:revisiting the concept of blood–brain barrier breakdown in ischemic stroke

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Neural Regeneration Research 2025年第7期20卷 1944-1956页

作者： Julia Castillo-gonzález Elena gonzález-Rey Institute of Parasitology and Biomedicine Lopez-Neyra(IPBLN) CSICPT SaludGranadaSpain

The blood–brain barrier constitutes a dynamic and interactive boundary separating the central nervous system and the peripheral *** tightly modulates the ion transport and nutrient influx,while restricting the entry of harmful factors,and selectively limiting the migration of immune cells,thereby maintaining brain *** the well-established association between blood–brain barrier disruption and most neurodegenerative/neuroinflammatory diseases,much remains unknown about the factors influencing its physiology and the mechanisms underlying its ***,the role of blood–brain barrier breakdown in the translational failure underlying therapies for brain disorders is just starting to be *** review aims to revisit this concept of“blood–brain barrier breakdown,”delving into the most controversial aspects,prevalent challenges,and knowledge gaps concerning the lack of blood–brain barrier *** moving beyond the oversimplistic dichotomy of an“open”/“bad”or a“closed”/“good”barrier,our objective is to provide a more comprehensive insight into blood–brain barrier dynamics,to identify novel targets and/or therapeutic approaches aimed at mitigating blood–brain barrier ***,in this review,we advocate for considering the diverse time-and location-dependent alterations in the blood–brain barrier,which go beyond tight-junction disruption or brain endothelial cell breakdown,illustrated through the dynamics of ischemic stroke as a case *** this exploration,we seek to underscore the complexity of blood–brain barrier dysfunction and its implications for the pathogenesis and therapy of brain diseases.

关键词： blood–brain barrier disruption drug delivery ischemic stroke neuroinflammation tight-junctions

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Modelling fuel loads of understorey vegetation and forest floor components in pine stands in NW Spain

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Forest Ecosystems 2022年第6期9卷 775-789页

作者： Jose A.Vega Stefano Arellano-Perez juan gabriel Alvarez-gonzalez Cristina Fernandez Enrique Jimenez Pedro Cuinas Jose María Fernandez-Alonso Daniel J.Vega-Nieva Fernando Castedo-Dorado Cecilia Alonso-Rego Teresa Fontúrbel Ana Daría Ruiz-gonzalez Centro de Investigacion Forestal de Lourizan PO Box 12736080PontevedraSpain Unidad de Gestion Ambiental y Forestal Sostenible(UXAFORES) Departamento de Ingeniería AgroforestalEscuela Politecnica Superior de IngenieríaUniversidad de Santiago de CompostelaCampus Universitario s/n27002LugoSpain Facultad de Ciencias Forestales Universidad Juarez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120DurangoMexico Departamento de Ingeniería y Ciencias Agrarias Universidad de LeonCampus de Ponferrada24401PonferradaSpain

In this study,310 destructively sampled plots were used to develop two equation systems for the three main pine species in NW Spain(***;*** and ***):one for estimating loads of understorey fuel components by size and condition(live and dead)and another one for forest floor *** systems of equations were simultaneously fitted for estimating fuel loads using overstorey,understorey and forest floor variables as *** systems of equations included both the effect of pine species and the effect of understorey compositions dominated by ferns-brambles or by woody species,due to their obvious structural and physiological *** general,the goodness-of-fit statistics indicated that the estimates were reasonably robust and accurate for all of the fuel *** best results were obtained for total understorey vegetation,total forest floor and raw humus fuel loads,with more than 76%of the observed variability explained,whereas the poorest results were obtained for coarse fuel loads of understory vegetation with a 53%of observed variability *** reduce the overall costs associated with the field inventories necessary for operational use of the models,the additive systems were fitted again using only overstorey variables as potential *** relationships for fine(<6 mm)and total understorey vegetation and total forest floor fuel loads were obtained,indicating the complexity of the forest overstorey-understorey and overstorey-forest floor ***,these models explained around 52%of the observed ***,equations estimating the total understorey vegetation and the total forest floor fuel loads based only on canopy cover were *** models explained only 26%-32%of the observed variability;however,their main advantage is that although understorey vegetation in forested landscapes is largely invisible to remote sensing,canopy cover can be estimated with moderate accuracy,allowin

关键词： Area-based approach Additive equation systems Live and dead fine fuel Pinus pinaster Pinus radiata Pinus sylvestris

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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)

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Targeting harmful effects of non-excitatory amino acids as an alternative therapeutic strategy to reduce ischemic damage

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Neural Regeneration Research 2025年第9期20卷 2454-2463页

作者： Victoria Jiménez Carretero IrisÁlvarez-Merz Jorge Hernández-Campano Sergei A.Kirov Jesús M.Hernández-Guijo Department of Pharmacology and Therapeutic School of MedicineUniv.Autónoma de MadridMadridSpain Ramón y Cajal Institute for Health Research(IRYCIS) Neurobiology-Research ServiceHospital Ramón y CajalMadridSpain Institute of Neurobiology Faculty of Mathematics and Natural SciencesHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neuroscience and Regenerative Medicine&Department of Neurosurgery Medical College of Georgia at Augusta UniversityAugustaGAUSA

The involvement of the excitatory amino acids glutamate and aspartate in ce rebral ischemia and excitotoxicity is ***,the role of non-excitatory amino acids in brain damage following a stroke or brain trauma remains largely *** release of amino acids by necrotic cells in the ischemic core may contribute to the expansion of the *** findings indicated that the reversible loss of field excitato ry postsynaptic potentials caused by transient hypoxia became irreversible when exposed to a mixture of just four non-excitatory amino acids(L-alanine,glycine,L-glutamine,and L-serine)at their plasma *** amino acids induce swelling in the somas of neurons and astrocytes during hypoxia,along with permanent dendritic damage mediated by N-methyl-D-aspartate *** N-methyl-D-aspartate receptors prevented neuronal damage in the presence of these amino acids during *** is likely that astroglial swelling caused by the accumulation of these amino acids via the alanine-serine-cysteine transporter 2 exchanger and system N transporters activates volume-regulated anion channels,leading to the release of excitotoxins and subsequent neuronal damage through N-methyl-D-aspartate receptor ***,previously unrecognized mechanisms involving non-excitatory amino acids may contribute to the progression and expansion of brain injury in neurological emergencies such as stroke and traumatic brain *** these pathways co uld highlight new therapeutic targets to mitigate brain injury.

关键词： cell swelling N-methyl-D-aspartate receptor non-excitatory amino acids stroke synaptic transmission

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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

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Effects of fire history on animal communities:a systematic review

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Ecological Processes 2022年第1期11卷 248-258页

作者： Tania Marisol gonzález juan David gonzález‑Trujillo Alberto Muñoz Dolors Armenteras Laboratorio de Ecología del Paisaje y Modelación de Ecosistemas ECOL‑MOD Departamento de BiologíaFacultad de CienciasUniversidad Nacional de ColombiaEdificio 421111321 BogotáColombia Departamento de Biología Facultad de CienciasUniversidad Nacional de ColombiaEdificio 421111321 BogotáColombia Departamento de Didáctica de Ciencias Experimentales Sociales y MatemáticasFacultad de EducaciónUniversidad Complutense de Madrid28040 MadridSpain CREAF 08193 Cerdanyola del VallèsCataloniaSpain

Fire is a natural agent with a paramount role in ecosystem functioning and biodiversity ***,it can also act as a negative force against many *** some knowledge of the interactions of fire and vegetation,there is no clear understanding of how different components of fire regimes(i.e.,severity,history,or frequency)influence known patterns of animal ***,we performed a systematic review on the global responses of arthropods,birds,mammals,reptiles,and amphibians to different fire ***,we focused on assessing how fire severity,history,and frequency modulate the effect of fire on the richness and abundance of faunal *** conducted a systematic review of 566 papers retrieved from the Scopus *** also scrutinized all the documents included in the meta‑analysis of Pastro et al.(Pastro et *** Ecol Biogeogr 23:1146–1156,2014).Our selection criteria excluded studies without data on species richness or *** also excluded studies without adequate controls and those without information about the fire regime of the study *** careful examination,we used data from 162 studies to perform a quantitative meta‑*** the 162 studies meeting our selection criteria,nearly 60%of the studies are from North America,25%from Australia,11%from Europe,and 4%from the *** to the ecological role of fire,90%of the studies were carried out in fire‑dependent ecosystems(i.e.,conifer forests,natural savannas,pastures).Finally,40%of the studies analyzed birds,22%mammals,and 20%*** meta‑analysis of the available evidence indicates that fire history is an important modulator of animal richness and *** negative or positive,animal responses depended on the time since the last fire *** that short‑term studies may not capture such a long‑term effect on fauna,this translates to more challenges at implementing fire management *** or not we can

关键词： Amphibians Arthropods Birds Fire regime components Mammals Reptiles

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Identification and functional characterization of fish IL‑17 receptors suggest important roles in the response to nodavirus infection

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Marine Life Science & Technology 2024年第2期6卷 252-265页

作者： Carmen gonzález‑Fernández Miguel A.García‑Álvarez Alberto Cuesta Department of Cell Biology and Histology Faculty of BiologyUniversity of Murcia30100 MurciaSpain Laboratoire d’écotoxicologie Centre de Lyon-VilleurbanneINRAEUR RiverLy69625 VilleurbanneFrance

Th17 is a lymphocyte T helper(Th)subpopulation relevant in the control and regulation of the immune response characterized by the production of interleukin(IL)-*** crucial cytokine family acts through their binding to the IL-17 receptors(IL-17R),having up to six *** the biology of fish Th17 is well-recognized,the molecular and functional characterization of IL-17 and IL-17R has been ***,our aim was to identify and characterize the IL-17R repertory and regulation in the two main Mediterranean cultured fish species,the gilthead seabream(Sparus aurata)and the European sea bass(Dicentrarchus labrax).Our in silico results showed the clear identification of six members in each fish species,from IL-17RA to IL-17RE-like,with well-conserved gene structure and protein domains with their human *** of them showed wide and constitutive transcription in naïve tissues but with highest levels in mucosal tissues,namely skin,gill or *** leucocytes,T mitogens showed the strongest up-regulation in most of the il17 receptors though il17ra resulted in inhibition by most ***,in vivo nodavirus infection resulted in alterations on the transcription of il17 *** nodavirus infection led to some increments in the il17ra,il17rb,il17rc and il17rd transcripts in the susceptible European sea bass,many down-regulations were observed in the resistant gilthead *** data identify the presence and conservation of six coding IL-17R in gilthead seabream and European sea bass as well as their differential regulation in vitro and upon nodavirus infection.

关键词： Th17 cells IL-17 receptors Immunity Teleost fish Nodavirus(NNV) Aquaculture

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