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Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the CoVID-19 lockdown

Journal of Environmental Sciences 2024年第9期143卷 99-115页

作者： Victor Almanza luis Gerardo Ruiz-Suárez Ricardo Torres-Jardón Agustín García-Reynoso Iván Y.hern.n.ez-Paniagua Institute for Atmospheric Sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the CoVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the new *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed no_(x)-limited and VoC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： CoVID-19 Mexico Megalopolis ozone Factor Separation Process Analysis

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High-repetition-rate source of nanosecond duration kA-current pulses driven by relativistic laser pulses

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High Power Laser Science and Engineering 2024年第3期12卷 106-115页

作者： Michael Ehret Jakub Cikhardt Philip Wykeham Bradford Iuliana-Mariana Vladisavlevici Tomas Burian Diego de luis Jose luis Henares Rubén hern.n.ez Martín Jon Imanol Apiñaniz Roberto Lera JoséAntonio Pérez-hern.n.ez João Jorge Santos Giancarlo Gatti Centro de Láseres Pulsados(CLPU) VillamayorSpain Czech Technical University in Prague Faculty of Electrical EngineeringPragueCzech Republic Univ.Bordeaux-CnRS-CEA Centre Lasers Intenses et Applications(CELIA)UMR 5107TalenceFrance Department of Radiation and Chemical Physics FZU-Institute of Physics of the Czech Academy of SciencesPragueCzech Republic

We report the first high-repetition-rate generation and simultaneous characterization of nanosecond-scale return currents of kA-magnitude issued by the polarization of a target irradiated with a PW-class high-repetition-rate titanium:sapphire laser system at relativistic *** present experimental results obtained with the VEGA-3 laser at intensities from5×10^(18)to 1.3×10^(20)W cm^(-2).A non-invasive inductive return-current monitor is adopted to measure the derivative of return currents of the order of kA ns-1and analysis methodology is developed to derive return *** compare the current for copper,aluminium and Kapton targets at different laser *** data show the stable production of current peaks and clear prospects for the tailoring of the pulse shape,which is promising for future applications in highenergy-density science,for example,electromagnetic interference stress tests,high-voltage pulse response measurements and charged particle beam *** compare the target discharge of the order of hundreds of nC with theoretical predictions and a good agreement is found.

关键词： current pulses electromagnetic pulse application high-power laser relativistic laser plasma

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Long-term monitoring reveals the effect of precipitation and silviculture on nothofagus regeneration in northern Patagonia mixed forests

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Ecological Processes 2024年第2期13卷 103-117页

作者： Georgina Sola Camila Mateo Alejandro Dezzotti Paula Marchelli hernán Attis Beltrán Renato Sbrancia luis Chauchard Marcelo González Pe?alba Martín Lara Verónica El Mujtar Consejo nacional de Investigaciones Científicas y Técnicas (ConICET ) Asentamiento Universitario San Martín de los Andes (AUSMA-UnCo) Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB) Instituto Nacional de Tecnología Agropecuaria (INTA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Departamento de Conservación y Manejo Parque Nacional Lanín- Administración de Parques Nacionales (PNL-APN)

Background Tree regeneration is a key component of resilience because it promotes post-disturbance recovery of forests. northwestern Patagonia from Argentina is occupied by nothofagus alpina（na）, n. obliqua（no）, and n. dombeyi（nd） forests that grow along an intense precipitation gradient, managed throughout shelterwood silvicultural system by technicians of the Lanin natural Reserve. The objective of this study was to evaluate the influence of seeding cuttings over the dynamics of nothofagus mixed forests across landscape（precipitation gradient） based mainly on the composition and abundance of tree regeneration, permanent sampling plots and generalized linear mixed models. In particular, we analysed:（i） the structure of sexual and asexual regeneration during nd > 20 years after harvest（the dynamics of managed forests）, and（ii） the structure of sexual regeneration in primary and managed forests after > 20 years of harvest（the effect of silviculture）.Results nd was the most abundant species in the regeneration of managed forests during all periods in both sites despite its lower contribution to the adult cohort. During the 10–20 years period after harvest, the humid site exhibited higher regeneration density than the mesic site(120,000 and 6000 ind ha-1, respectively), and it decreased afterwards. The number of established regeneration（> 2 m height） was lower for na in the mesic site and for no in the humid site(0 and 57 ind ha-1, respectively). However, in comparison to no, na showed a higher number of sprouted stumps and sprouts per stump, and a higher sprout height in the mesic site. no exhibited higher sprout mortality in the humid site. Finally, the regeneration of primary forests showed lower density and height, and a more balanced composition than that of managed *** The silvicultural effects on the mixed forest regeneration dynamics was strongly influenced by the condition of sites. Therefore, management prescriptions should be adj

关键词： nothofagus alpina nothofagus obliqua nothofagus dombeyi Basal sprouting Shelterwood silvicultural system Ecological resilience

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Accuracy of tree mapping based on hand-held laser scanning comparing leaf-on and leaf-off conditions in mixed forests

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Journal of Forestry Research 2024年第5期35卷 14-25页

作者： Frederico Tupinambá-Simões Adrián Pascual Juan Guerra-hern.n.ez Cristóbal ordóñez Tiago de Conto Felipe Bravo iuFoR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIAValladolidSpain Department of Geographical Sciences University of MarylandCollege ParkMD 20742USA Forest Research Centre School of AgricultureUniversity of LisbonTapada da Ajuda1349‑017 LisbonPortugal

The use of mobile laser scanning to survey forest ecosystems is a promising,scalable technology to describe forest 3D structures at high *** confirm the con-sistency in the retrieval of forest structural parameters using hand-held laser scanning(HLS),before operationalizing the method,confirming the data is *** analyzed the per-formance of tree-level mapping based on HLS under differ-ent phenology conditions on a mixed forest in western Spain comprising Pinus pinaster and two deciduous species,Alnus glutinosa and Quercus *** area was surveyed twice during the growing season(July 2022)and once in the deciduous season(February 2022)using several scan-ning *** reference data(418 trees,15 snags)was used to calibrate the HLS data and to assess the influence of phenology when converting 3D data into tree-level attrib-utes(DBH,height and volume).The HLS-based workflow was robust at isolating tree positions and recognizing stems despite changes in ***-six percent of all pairs matched below 65 *** DBH,phenology barely altered *** observed a strong agreement when comparing HLS-based tree height *** values exceeded 2 m when comparing height measurements,confirming height data should be carefully used as reference in remote sensing-based inventories,especially for deciduous *** volume was more precise for pines(r=0.95,and rela-tive RMSE=21.3–23.8%)compared to deciduous species(r=0.91–0.96,and relative RMSE=27.3–30.5%).HLS data and the forest structural complexity tool performed remark-ably,especially in tree positioning considering mixed forests and mixed phenology conditions.

关键词： Precision forestry Forest monitoring Mobile laser scanning Forest inventory

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Resilience to structural and molecular changes in excitatory synapses in the hippocampus contributes to cognitive function recovery in Tg2576 mice

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neural Regeneration Research 2024年第9期19卷 2068-2074页

作者： Carolina Aguado Sara Badesso JoséMartínez-hern.n.ez Alejandro Martín-Belmonte Rocío Alfaro-Ruiz Miriam fernández Ana Esther Moreno-Martínez Mar Cuadrado-Tejedor Ana García-osta Rafael Luján Synaptic Structure Laboratory Instituto de Investigación en Discapacidades Neurológicas(IDINE)Department of Medical SciencesFacultad de MedicinaUniversidad de Castilla-La ManchaCampus BiosanitarioAlbaceteSpain Gene Therapy for neurological Disease Program Center for Applied Medical Research(CIMA)University of NavarraInstituto de Investigación Sanitaria de Navarra(IdiSNA)PamplonaSpain Pharmacology Unit Department of Pathology and Experimental TherapeuticsFaculty of Medicine and Health SciencesInstitute of NeurosciencesUniversity of BarcelonaBarcelonaSpain neuropharmacology and Pain Group Neuroscience ProgramInstitut d’InvestigacióBiomèdica de BellvitgeIDIBELLL’Hospitalet de LlobregatSpain Department of Pathology Anatomy and PhysiologySchool of MedicineUniversity of NavarraPamplonaSpain UniversitéGrenoble Alpes Grenoble Institut des NeurosciencesGrenobleFrance

Plaques of amyloid-β(Aβ)and neurofibrillary tangles are the main pathological characteristics of Alzheimer’s disease(AD).However,some older adult people with AD pathological hallmarks can retain cognitive *** the factors that lead to this cognitive resilience to AD offers promising prospects for identifying new therapeutic *** hypothesis focuses on the contribution of resilience to changes in excitatory synapses at the structural and molecular levels,which may underlie healthy cognitive performance in aged AD *** the Morris Water Maze test,we selected resilient(asymptomatic)and cognitively impaired aged Tg2576 *** the enzyme-linked immunosorbent assay showed similar levels of Aβ42 in both experimental groups,western blot analysis revealed differences in tau pathology in the pre-synaptic supernatant *** further investigate the density of synapses in the hippocampus of 16-18 month-old Tg2576 mice,we employed stereological and electron microscopic *** findings indicated a decrease in the density of excitatory synapses in the stratum radiatum of the hippocampal CA1 in cognitively impaired Tg2576 mice compared with age-matched resilient Tg2576 and non-transgenic ***,through quantitative immunoelectron microscopy in the hippocampus of impaired and resilient Tg2576 transgenic AD mice,we uncovered differences in the subcellular localization of glutamate ***,the density of GluA1,GluA2/3,and mGlu5 in spines and dendritic shafts of CA1 pyramidal cells in impaired Tg2576 mice was significantly reduced compared with age-matched resilient Tg2576 and non-transgenic ***,the density of GluA2/3 in resilient Tg2576 mice was significantly increased in spines but not in dendritic shafts compared with impaired Tg2576 and non-transgenic *** subcellular findings strongly support the hypothesis that dendritic spine plasticity and synaptic machinery in the hippocampus play cr

关键词： aging Alzheimer´s disease cognitive hippocampus immunoelectron microscopy resilience synapse

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Are we ready to use new endoscopic scores for ulcerative colitis?

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World Journal of Gastroenterology 2024年第10期30卷 1466-1469页

作者： Rodrigo Quera Paulina núñez F Universidad de los Andes Inflammatory Bowel Disease ProgramClinica Universidad de los AndesDigestive Disease CenterSantiago 7600976RMChile Digestive Disease Center Inflammatory Bowel Disease ProgramClínica Universidad de los AndesSantiago 7620157Chile Department of Gastroenterology Universidad de Chile-Hospital San Juan de DiosSantiago 770123Chile

For ulcerative colitis(UC),the variability in inflammatory activity along the colon poses a challenge in *** focus on achieving endoscopic healing in UC is evident,where the UC Endoscopic Index of Severity and Mayo Endoscopic Subscore are commonly used for ***,these indices primarily consider the most severely affected *** et al recent study validates the Toronto Inflammatory Bowel Disease Global Endoscopic Reporting(TIGER)score offering a comprehensive assessment of inflammatory activity across diverse segments of the colon and rectum and a reliable index correlating strongly with UC Endoscopic Index of Severity and moderately with Mayo Endoscopic Subscore(MES).Despite recommendation,certain aspects warrant further *** calprotectin,an intermediate target,correlates with TIGER and should be *** TIGER scores defining endoscopic remission and response,evaluating agreement with histological activity,and assessing inter-endoscopist agreement for TIGER require *** the correlation between TIGER and intestinal ultrasound,akin to MES,adds value.

关键词： Ulcerative colitis Sigmoidoscopy Colonoscopy Score index

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Using fused filament fabrication to improve the tribocorrosion behaviour of 17-4 PH SS in comparison to other metal forming techniques

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Friction 2024年第10期12卷 2325-2343页

作者： Cristina GARCÍA-CABezÓn Juan Alfonso nARAnJo Celia GARCÍA-hern.n.ez Cristina BERGES Gemma HERRAnZ fern.n.o MARTÍn-PEDRoSA Materials Engineering E.I.I.Universidad de ValladolidValladolid 47011Spain InEI-Escuela Técnica Superior de Ingeniería Industrial(ETSII) Universidad de Castilla La ManchaCastilla-La Mancha 13071Spain

Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and *** technology is similar to the conventional metal injection moulding(MIM)process,consisting of the feedstock preparation of metal powder and polymer binders,followed by layer-by-layer 3D printing(FFF)or injection(MIM)to create green parts and,finally,debinding and ***,both technologies provide near-dense *** work presents an in-depth study of the processing method’s *** porosity,microstructure,hardness,corrosion,and tribocorrosion behaviour are compared for 17-4 PH SS samples processed from powder by additive manufacturing using FFF and MIM,as well as conventional powder metallurgy(PM)*** samples exhibited the highest macro and microhardness,while corrosion behaviour was similar for both MIM and FFF samples,but superior in comparison to conventional PM ***,the FFF-as fabricated samples displayed a significant improvement in tribocorrosion resistance that could be explained by the higher proportion of delta ferrite and retained austenite in their microstructure.

关键词： 17-4 PH SS fused filament fabrication(FFF) metal injection moulding(MIM) corrosion behaviour powder metallurgy(PM) tribocorrosion behaviour

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Frontier of the Paleo-Tethys ocean in the western Mediterranean:Isotopic(Sm-nd)constraints on sources of Devonian units from Menorca Island

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Geoscience Frontiers 2024年第5期15卷 323-338页

作者： Ricardo Arenas Jose M.Fuenlabrada Cristian Timoner Rubén Díez fernández Esther Rojo-Pérez Departamento de Mineralogía y Petrología and Instituto de Geociencias(UCM CSIC)Universidad ComplutenseMadridSpain Unidad de Geocronología(CAI de Ciencias de la Tierra y Arqueometría) Universidad ComplutenseMadridSpain Bayerisches Geoinstitut University of BayreuthBayreuthGermany Instituto Geológico y Minero de España–CSIC SalamancaSpain

The c.1000-m-thick pre-orogenic Devonian mainly metapelitic sequence of north Menorca Island shows a fairly complete stratigraphic *** rocks of this sequence indicate gradually increasing deeper marine conditions of sedimentation towards its uppermost ***,the obtained sedimentary characteristics resemble those related to a deep and narrow basin-associated *** sills of Ti-augite-bearing alkaline gabbros occur within the Devonian *** intensity of Variscan deformation increases downwards through the *** to the characteristics of the Devonian sequence and its location within the Variscan orogen,a correlation with similar units located in the southern sectors of the Central Iberian Zone(Iberian Massif)is *** Devonian metapelitic rocks have geochemical characteristics suggesting that they represent moderately recycled mature siliciclastic sediments,generated from erosion of distant source areas belonging to an upper continental *** relatively narrow range of variation observed in initial^(143)nd/^(144)nd ratios supports a similar source for the Menorcan slates(0.51165–0.51182).However,a marked trend is observed in these isotope ratios,from lower values at the base of the stratigraphic column(minimum value of 0.511941)to higher values at the top(maximum value of 0.512131).The^(147)Sm/^(144)nd ratios vary between 0.1074 and 0.1238,within the range defined for siliciclastic rocks with felsic crustal *** nd model ages define a narrow range between 1496 Ma and 1754 Ma(Late Paleoproterozoic–Early Mesoproterozoic),and they are consistently younger *** data rule out a provenance from the erosion of the West Africa Craton,as they are more compatible with a provenance from regions located in the Trans-Saharan Belt or Sahara *** characteristics of the Menorcan Devonian sequence are compatible with its deposition in a narrow and deep peri-Gondwanan transtensional basin,gener

关键词： Western Paleo-Tethys frontiers Menorca Island Sm-nd isotopic constraints Devonian sequence provenance in Gondwana

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Sex-dependent resilience to extreme drought events: implications for climate change adaptation of a South American endangered tree species

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Ecological Processes 2024年第2期13卷 48-60页

作者： Sergio Piraino Martín Ariel Hadad Yanina Antonia Ribas-fernández Fidel Alejandro Roig Laboratorio de Dendrocronología e Historia Ambiental (IAnIGLA ConICET ) Facultad de Ciencias Agrarias Universidad Nacional de Cuyo Laboratorio de Dendrocronología de Zonas áridas (CIGEoBIo ConICET ) Gabinete de Geología Ambiental (INGEO UNSJ) Hémera Centro de observación de la Tierra Facultad de Ciencias Universidad Mayor

Background Recent changes in climatic trends are resulting in an increased frequency and intensity of extreme events, with unknown effect on ecosystem dynamics in the near future. Extreme drought episodes are recognized as disturbance factors capable of modifying forest dynamics and tree growth. Within this context, dioecious tree species may be impacted by climatic extremes, affecting male/female proportions and, consequently, reproductive processes and species persistence. Therefore, there is an urgent need for species-specific assessments of growth tolerance to extreme dry spells in dioecious tree species, to establish effective conservation strategies for these particular natural resources. Araucaria araucana(araucaria), an endangered dioecious Patagonian tree species, has recently undergone decay and mortality episodes in response to increasing dry climatic conditions. While sex-dependent tolerance to extreme drought episodes has been assessed in the species' humid distribution range, there is still a lack of information on the gender-based resilience of trees growing in the drier environments of the species' *** We reconstructed, through dendrochronological methods, the sex-dependent response of 105 araucaria individuals(55 female and 50 male trees) to five regional extreme dry spells employing a set of different indices. Resistance, recovery period, and average growth reduction of standardized tree-ring growth were examined, analysing the effect of biotic(sex, pre-drought stem tree growth) and abiotic(local climatic conditions before, during, and after extreme climatic episodes) factors on tree *** Sex influences only the species resistance to climatic disturbance, with male individuals showing lower tolerance to extreme drought events. Pre-drought radial growth rates and local meteorological conditions preceding, during, and following extreme dry spells strongly modulated araucaria radial growth resilience regardless of tree s

关键词： Araucaria Climate change Dendrochronology Extreme drought event Resilience

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Solar-assisted photocatalytic water splitting using defective Uio-66 solids from modulated synthesis

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nano Research 2024年第5期17卷 4134-4150页

作者： Celia M.Rueda-navarro María Cabrero-Antonino Paula Escamilla Valentín Díez-Cabanes Dong Fan Pedro Atienzar Belén Ferrer Ignacio Vayá Guillaume Maurin Herme G.Baldoví Sergio navalón Departamento de Química Universitat Politècnica de ValènciaCamino de Vera s/nValencia 46022Spain Instituto de Ciencia Molecular(ICMoL) Universitat de ValènciaPaterna 46980Spain ICGM Univ.MontpellierCNRSENSCMMontpellier34095France Instituto de Tecnología Química(UPV-CSIC) Universitat Politècnica de ValènciaAvenida de los Naranjos s/nValencia 46022Spain

Metal-organic frameworks(MoFs)are attracting increasing interests as photocatalysts for solar-driven hydrogen production from *** paper reports on a comparative study of using either acetic acid(AA)or trifluoroacetic acid(TFA)as the representative Uio-66 organic modulators for synthesizing visible light responsive Uio-66(Zr)-X(X:nH_(2) or no_(2))photocatalysts for water *** results show that photocatalytic hydrogen generation from a water/methanol mixture can be improved by varying the nature and amount of the modulator employed to prepare the different Uio-66(Zr)-X(X:nH_(2) or no_(2))solid ***-66(Zr)-nH_(2) was the most active photocatalyst,followed by Uio-66(Zr)-no_(2),both prepared with 12 equivalents of AA with respect to the organic *** Uio-66(Zr)-nH_(2) solid was more active than the parent MoF in photocatalytic overall water splitting(oWS)(H_(2) and o_(2) production of 450 and 160μmol·g^(-1),respectively,in 5 h;apparent quantum yield(AQY)at 400 nm of 0.06%)in the absence of methanol and compares favourably with analogous *** on the photocatalytic activity of the most active solids of both series was obtained by means of a series of techniques,including ultraviolet-visible(UV-vis)diffuse reflectance,X-ray photoelectron spectroscopy(XPS),laser flash photolysis(LFP),electron spin resonance(ESR),photoluminescence and photoelectrochemical measurements together with density functional theory(DFT)*** results showed that organic acid modulators can be used to enhance the photocatalytic activity of missing linker Uio-66 defective materials in solar-powered water splitting.

关键词： heterogeneous photocatalysis metal-organic frameworks(MoFs) Uio-66 materials carboxylic acid modulators water splitting solar light

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