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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

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Ecological Processes 2024年第1期13卷 132-143页

作者： Luiz Santini Jr. Dylan Craven Daigard Ricardo Ortega Rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero cristina Aravena Torres Fidel A.Roig Ariel A.Mu?oz Alejandro Venegas-gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of Nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

Sustained adenosine release:Revealing its impact on osteogenic signalling pathways of human mesenchymal stromal cells

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Engineered Regeneration

Engineered Regeneration 2024年第2期5卷 255-268页

作者： Hadi Hajiali Jane McLaren cristina gonzalez-García Salah Abdelrazig Dong-Hyun Kim Matthew J.Dalby Manuel Salmerón-Sánchez Felicity R.A.J.Rose School of Pharmacy Nottingham Biodiscovery InstituteUniversity of NottinghamNottinghamUK Healthcare Technologies Institute School of Chemical EngineeringUniversity of BirminghamBirminghamUK Centre for the Cellular Microenvironment University of GlasgowGlasgowUK Centre for Analytical Bioscience Advanced Materials&Healthcare Technologies DivisionSchool of PharmacyUniversity of NottinghamNottinghamUK Marine Microbiomics Program in BiologyDivision of Science and MathematicsNew York University Abu Dhabi(NYUAD)P.O.Box 129188Abu DhabiUnited Arab Emirates

Non-healing fractures,a global health concern arising from trauma,osteoporosis,and tumours,can lead to severe ***,integral to cellular energy metabolism,gains prominence in bone regeneration via adeno-sine A2 B receptor *** study introduces a controlled-release system for localized adenosine delivery,fostering human mesenchymal stromal cell(hMSC)differentiation into functional bone *** study investi-gates how the ratio of lactic acid to glycolic acid in microparticles can influence adenosine release and explores the downstream effects on gene expression and metabolic profiles of osteogenic differentiation in hMSCs cultured in growth and osteoinductive *** into adenosine-modulated signalling pathways during MSC differenti-ation,with osteogenic factors,provide a comprehensive understanding of the pathways *** gene expression and metabolic profiles unravels adenosine’s regulatory mechanisms in MSC *** adenosine release from microparticles induces mineralization,synergizing with osteogenic media supplements,showcasing the potential of adenosine for treating critical bone defects and metabolic *** study high-lights the efficacy of a polymeric microparticle-based delivery system,offering novel strategies for bone *** adenosine’s roles and associated signalling pathways advances our comprehension of molecular mech-anisms steering bone regeneration,propelling innovative biomaterial,combined with metabolites,approaches for clinical use.

关键词： Adenosine release Osteogenic signalling pathways Human mesenchymal stromal cells Bone regeneration

Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

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Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO Javier PRECIADO-GARBAYO Jorge SEVIL Francisco GUTIERREZ Juan JmartinEZ Sonia martin-LOPEZ Miguel gonzalez-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain Department of Earth Sciences Universidad de ZaragozaZaragoza 50009Spain Department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

Effect of asphalt thin beams mixed with three nominal maximum aggregate sizes in the bending beam rheometer on the prediction of thermal properties of bituminous material

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Frontiers of Structural and Civil Engineering 2017年第1期11卷 1-7页

作者： Chun-Hsing HO Maria Francisca martinez gonzalez cristina Pilar martin LINARES Department of Civil Engineering Construction Management and Environmental Engineering Northern Arizona UniversityFlagstaff Arizona 86001 USA

The objective of this research is to evaluate an impact of asphalt mixture beams with varying sizes of aggregate in the Bending Beam Rheometer （BBR） for testing/predicting thermal cracking properties of asphalt pavements. The BBR test has following benefits： the equipment is cheaper, it uses smaller specimens, faster conditioning, easier availability for quality control, easier to manage, etc. However some concerns have been raised： some consider that the size of the aggregate may affect the test＇s results; the other concern is that such small beams cannot represent the whole properties of the asphalt pavement. To address these criticisms, imaging techniques, statistical analysis, and viscoelastic modeling are used. Asphalt thin beams prepared with three different nominal maximum aggregate size （NMAS）（12.5mm, 9.5 mm, and 4.75 mm） were tested at three different temperatures （-18℃, -24℃, and -30℃）. Based on results from statistical analyses and viscoelasticity, the ratio of asphalt binders and voids and stiffness differences among the three NMAS specimens are not significant, meaning that the impact of asphalt thin beams prepared with the three NMAS on the prediction of thermal cracking is minimal and can be neglected.

关键词： bending beam rheometer thin beams thermal cracking

Ultrasmall CoS nanoparticles embedded in heteroatom-doped carbon for sodium-ion batteries and mechanism explorations via synchrotron X-ray techniques

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Journal of Energy Chemistry 2023年第4期79卷 373-381页

作者： Congcong Liu Qiongqiong Lu Mikhail V.Gorbunov Ahmad Omar Ignacio G.gonzalez martinez Panpan Zhao martin Hantusch Antonius Dimas Chandra Permana Huanyu He Nikolai Gaponik Daria Mikhailova Leibniz Institute for Solid State and Materials Research(IFW)Dresden e.V. Helmholtzstraße 2001069 DresdenGermany Inorganic Chemistry II Technische Universität DresdenBergstraße 6601069 DresdenGermany Physical Chemistry Technische Universität DresdenZellescher Weg 1901069 DresdenGermany

Transition metal sulfides have been regarded as promising anode materials for sodium-ion batteries(SIB).However,they face the challenges of poor electronic conductivity and large volume change,which result in capacity fade and low rate *** this work,a composite containing ultrasmall CoS(~7 nm)nanoparticles embedded in heteroatom(N,S,and O)-doped carbon was synthesized by an efficient one-step sulfidation process using a Co(Salen)*** ultrasmall CoS nanoparticles are beneficial for mechanical stability and shortening Na-ions diffusion ***,the N,S,and O-doped defect-rich carbon provides a robust and highly conductive framework enriched with active sites for sodium storage as well as mitigates volume expansion and polysulfide *** anode for SIB,CoS@HDC exhibits a high initial capacity of 906 mA h g^(-1)at 100 mA g^(-1)and a stable long-term cycling life with over 1000 cycles at 500 mA g^(-1),showing a reversible capacity of 330 mA h g^(-1).Meanwhile,the CoS@HDC anode is proven to maintain its structural integrity and compositional reversibility during ***,Na-ion full batteries based on the CoS@HDC anode and Na_(3)V_(2)(PO_(4))_(3)cathode demonstrate a stable cycling behavior with a reversible specific capacity of~200 m A h g^(-1)at least for 100 ***,advanced synchrotron operando X-ray diffraction,ex-situ X-ray absorption spectroscopy,and comprehensive electrochemical tests reveal the structural transformation and the Co coordination chemistry evolution of the CoS@HDC during cycling,providing fundamental insights into the sodium storage mechanism.

关键词： Sodium-ion batteries Cobalt sulfide nanoparticles Heteroatom-doped porous carbon matrix Synchrotron X-ray techniques Reaction mechanisms

Neuroprotective action of Ginkgo biloba on the enteric nervous system of diabetic rats

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World Journal of Gastroenterology 2011年第7期17卷 898-905页

作者： Glasiella gonzalez Perez da Silva Jacqueline Nelisis Zanoni Nilza cristina Buttow Department of Morphological Sci-ences Universidade Estadual de Maringá Av. Colombo 5790Bloco H-79 CEP 87020-900 Maringá PR Brazil

AIM: To investigate the effect of Ginkgo biloba extract on the enteric neurons in the small intestine of diabetic rats. METHODS: Fifteen Wistar rats were divided into three groups: control group (C), diabetic group (D) and diabetic-treated (DT) daily with EGb 761 extract (50 mg/kg body weight) for 120 d. The enteric neurons were identified by the myosin-V immunohistochemical technique. The neuronal density and the cell body area were also analyzed. RESULTS: There was a significant decrease in the neuronal population (myenteric plexus P = 0.0351; submucous plexus P = 0.0217) in both plexuses of the jejunum in group D when compared to group C. With regard to the ileum, there was a significant decrease (P = 0.0117) only in the myenteric plexus. The DT group showed preservation of the neuronal population in the jejunum submucous plexus and in the myenteric plexus in the ileum. The cell body area in group D increased significantly (P = 0.0001) in the myenteric plexus of both segments studied as well as in the ileum submucosal plexus, when compared to C. The treatment reduced (P = 0.0001) the cell body area of the submucosal neurons of both segments and the jejunum myenteric neurons. CONCLUSION: The purified Ginkgo biloba extract has a neuroprotective effect on the jejunum submucous plexus and the myenteric plexus of the ileum of diabetic rats.

关键词：银杏叶提取物神经保护作用糖尿病大鼠神经系统肠道肌间神经丛 Wistar大鼠神经元群

Avian sibling cannibalism: Hoopoe mothers regularly use their last hatched nestlings to feed older siblings

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Zoological Research 2022年第2期43卷 265-274页

作者： Juan JoseSoler Manuel martin-Vivaldi Sona Nuhlickova cristina Ruiz-Castellano Monica Mazorra-Alonso Ester martinez-Renau Manfred Eckenfellner Jan Svetlik Herbert Hoi Departamento de Ecologia Funcional y Evolutiva Estacion Experimental de Zonas Aridas(EEZA-CSIC)Almeria E-04120Spain Unidad Asociada Coevolucion:Cucos Hospedadores y Bacterias SimbiontesUniversidad de GranadaGranada E-18003Spain Departamento de Zoologia Facultad de CienciasUniversidad de GranadaGranada E-18003Spain Department of Ecology Faculty of Natural SciencesComenius UniversityBratislava SK-84215Slovakia Konrad Lorenz Institute of Ethology Department of Interdisciplinary Life SciencesUniversity of Veterinary MedicineVienna A-1160Austria

Sibling cannibalism is relatively common in nature,but its evolution in birds and certain other vertebrates with extended parental care had been ***,however,we demonstrate its regular occurrence in two European populations of the Eurasian hoopoe(Upupa epops)and explore possible adaptive and non-adaptive *** showed that sibling cannibalism was more frequently detected in Spain(51.7%)than in Austria(5.9%).In these two populations,the hoopoes laid similar clutch sizes,resulting in similar fledging production,but hatching failures were more frequent in the northern ***,having more nestlings condemned to die in the southern population may explain the higher incidence of sibling *** accordance with this interpretation,hatching span and failure,but not breeding date,explained the probability of sibling cannibalism in the Spanish hoopoes,while all three variables predicted brood reduction ***,experimental food supply reduced the probability of sibling cannibalism,but not the intensity of brood ***,females allocated fewer resources to the smallest nestlings when they were going to starve,but not necessarily when they were going to be used as food for their *** results suggest that hoopoes produce extra eggs that,in the case of reduced hatching failure and food scarcity,produce nestlings that are used to feed older *** findings provide the first evidence that sibling cannibalism occurs regularly in a bird species,thus expanding our evolutionary understanding of clutch size,hatching asynchrony,parent-offspring conflict,infanticide,and sibling cannibalism in the animal kingdom.

关键词： Brood reduction Clutch size Hatching asynchrony Ice-box hypothesis Infanticide Siblicide Sibling hierarchy Upupa epops

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

In vitro antioxidant,antilipoxygenase and antimicrobial activities of extracts from seven climbing plants belonging to the Bignoniaceae

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Journal of Integrative Medicine 2018年第4期16卷 255-262页

作者： Carola Analla Torres cristina Marisel Perez Zamora Maria Beatriz Nunez Ana Maria gonzalez Laboratory of Microbiology and Pharmaceutical Technology Department of Basic and Applied SciencesNational University of Chaco AustralPresidencia Roque Saenz Pena 3700ChacoArgentina National Council for Scientific and Technical Research(CONICET) Godoy Cruz 2290Buenos Aires C1425FQBArgentina Institute of Botany of the Northeast(IBONE-CONICET) Sargento Juan Bautista Cabral 2131CorrientesArgentina

Objectives： This study aimed to evaluate the in vitro antioxidant capacity, to determine the anti-inflammatory effect due to lipoxygenase inhibition and to test the antimicrobial activity of ethanolic extracts from leaves of seven climbing species belonging to the Bignoniaceae family. These species are Adenocalyrnrna rnarginatum （Cham.） DC., Amphilophium vauthieri DC., Cuspidaria convoluta （VEIL） A. H. Gentry, Dolichandra dentata （K. Schum.） L. G. Lohmann, Fridericia caudigera （S. Moore） L. G. Lohmann, Fridericia chica （Bonpl.） L. G. Lohmann and Tanaecium selloi （Spreng.） L. G. Lohmann. Methods： The antioxidant activity was evaluated using three methods, 2,2＇-azino-bis（3-ethylbenzothiazo line-6-sulfonic acid）（ABTS）, 2,2-diphenyl-l-picrylhydrazyl （DPPH）, and ferric reducing antioxidant power. Lipoxygenase-inhibiting activity was assayed spectrophotometrically; the result was expressed as percent inhibition. The antimicrobial activity was assessed using the agar disk diffusion method. Minimal inhibitory concentration （MIC） and minimal bactericidal]fungicidal concentration were also determined for each extract against 12 pathogenic bacterial strains of Staphylococcus aureus and seven fungal strains of the Candida genus. The identification of the major compounds present in the most promising extract was established by high-performance liquid chromatography-tandem mass spectrometry. Results： C convoluta, F. caudigera, and F. chica exhibited the best antioxidant activity by scavenging DPPH and ABTS~ radicals and reducing Fe3＋ ion. These extracts showed a notable inhibition of lipnxygenase. F. caudigera was found to have the lower MIC value against S. aureus strains and six Candida species. The extracts of F. caudigera and C. convoluta were active even against methicillin-resistant S. aureus. C convoluta had higher total phenol content, better antioxidant activity and superior anti- inflammatory and antimicrobial activity. The main phenolic compounds found in this extract

关键词： Cuspidaria Fridericia Antioxidants Lipoxygenase Antimicrobials Herbal drugs Free radical scavengers