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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 iv.n Y.Hernández-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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Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems

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Journal of Mountain Science 2024年第1期21卷 33-48页

作者： Francis Levi A.DURAnO Jon Marx SARMIEnTO Larry n.DIGAL Pedro A.ALVIOLA iv School of Management University of the Philippines MindanaoDavao City 8000Philippines

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation

关键词： Cocoa farms Cobb-Douglas production function Elevation Philippines Stochastic frontier analysis Technical efficiency

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Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests

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Journal of Mountain Science 2024年第9期21卷 2986-3000页

作者： Anthony guerra Fressia n.AMES-MARTÍnEZ Ernesto C.RODRÍGUEZ-RAMÍREZ Postgraduate Programme in Agronomy/Plant Physiology Department of Biology-Institute of natural Sciences Federal University of LavrasLavras 37203-202Minas Gerais 30000-31999Brazil Laboratory of Biotechnology and Molecular Biology Continental UniversitySan Antonio UrbanizationHuancayo 12000Peru Ecology and Biodiversity Research Programme ANDINUS AssociationMiguel Grau Street 370Huancayo 12000Peru Dendrochronology Laboratory Continental UniversitySan Carlos Avenue 1980Huancayo 12000Peru

Polylepis(Queñua)is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism,which may be particularly threatened by climate *** anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience,resistance,and recovery to extreme *** the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively,our knowledge is relatively limited to quantitative differences in the main xylem *** address this gap,we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters).We selected hydraulic diameter,vessel density,vessel grouping index,solitary vessel index,vulnerability index,mesomorphy index,vessel element length,fiber length,fiber wall thickness,fiber lumen diameter,and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric *** performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic *** wood anatomical traits(vessel grouping index,vulnerability index,and fiber wall thickness)were dissimilar between xeric-and mesic-Polyelpis *** study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel *** findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna *** evaluating the effects of drought on wood anatomical characteristics and ecological function,we demonstrate the capacity of tree species to adapt and endure climate-related changes,thereby emphasizing their resilience and ada

关键词： Carlquist indices Climatic resilience Vessel traits Fiber Functional trait Hydric stress

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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-Hernández 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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Mental health in organizations from a healthcare analytics framework:taxonomic model,trends,and impact of COVID-19

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Journal of Management Analytics 2024年第1期11卷 62-86页

作者： Jorge iv.n Pérez Rave Carlos Mario Zapata Jaramillo Gloria Patricia Jaramillo Álvarez IDInnOV research group IDINNOV S.A.SMedellínColombia Department of Computing and Decision Sciences Universidad Nacional de ColombiaMedellínColombia

Mental disorders negatively affect employee well-being and organizational *** face a challenge in terms of how to manage mental *** paper clarifies three issues(underlying patterns,trends,and impact of COVID-19)regarding the scientific study of mental health in organizations from a healthcare analytics *** framework comprises eight stages considering a text-driv.n approach with scientific corpora assisted by linguistic/computational and statistical *** study discovers a new taxonomic model comprising five patterns in the scientific discourse on the *** analyses reveal imbalances and concerns regarding the interests associated with the patterns,which is reinforced by examining patterns“before”and“during”*** paper complements psychological/epidemiological studies on mental health in organizations from a healthcare analytics perspective.

关键词： Healthcare analytics healthcare management analytics mental health scientific discourse text analytics taxonomy COVID-19 management analytics

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Wood anatomical acclimation in the endemic genus Polylepis in Peruvian Andean forests

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Journal of Mountain Science 2024年第09期 2986-3000页

作者： Anthony guerra Fressia n.AMES-MARTínEZ Ernesto C.RODRíGUEZ-RAMíREZ Postgraduate Programme in Agronomy/Plant Physiology Department of Biology-Institute of natural Sciences Federal University of Lavras Laboratory of Biotechnology and Molecular Biology Continental University Ecology and Biodiversity Research Programme ANDINUS Association Dendrochronology Laboratory Continental University

Polylepis(Que?ua) is a dominant woody plant genus in Andean Puna forests that occurs in a wide range of montane habitats and is ecologically diverse in endemism, which may be particularly threatened by climate change. Wood anatomical traits are essential for understanding how plants adjust their ecophysiological requirements and maximize their resilience, resistance, and recovery to extreme climates. Although the effects of extreme climatic conditions in high altitude ecosystems have been studied extensively, our knowledge is relatively limited to quantitative differences in the main xylem tissues. To address this gap, we assessed the acclimation of wood anatomical traits in six Peruvian Andean Polylepis species with different water availability(semi-dry with high moisture and semiarid with dry winters). We selected hydraulic diameter, vessel density, vessel grouping index, solitary vessel index, vulnerability index, mesomorphy index, vessel element length, fiber length, fiber wall thickness, fiber lumen diameter, and total fiber diameter that can provide relevant eco-wood anatomical acclimation to hydric stress. We performed multivariate analysis to determine the leading dimensions of covariation among Polylepis species and climatic factors. Specific wood anatomical traits(vessel grouping index, vulnerability index, and fiber wall thickness) were dissimilar between xeric-and mesicPolyelpis species. This study demonstrates that wood anatomical traits in Peruvian Andean Polylepis species provides high-resolution and long-term eco-wood anatomical signals on how climate oscillations drive the acclimation processes of fiber and vessel traits. Our findings underscore the significance of xylem hydraulic adjustment to various hydrological environments in Andean puna forests. By evaluating the effects of drought on wood anatomical characteristics and ecological function, we demonstrate the capacity of tree species to adapt and endure climate-related changes, thereby emphasi

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极干旱胁迫对雀麦、多年生黑麦草生长和体内水分的影响

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草地学报 2024年

作者：张咏梅胡海英白小明 Matthew Cory García-Favre Javier Ordó?ez iv.n P 甘肃农业大学干旱生境作物学国家重点实验室宁夏大学林业与草业学院甘肃农业大学草业学院农业与环境学院梅西大学坎佩奈克农艺研究所

为研究极端干旱对牧草生长的影响，选择多年生黑麦草（Lolium Perenne）(Lp)和雀麦（Bromus Valdivianus）(Bv)给予80%?85%植物有效水（Plant available water， PAW）和20%?25% PAW 2种水分处理，分析2牧草生长及体内水分状况对干旱胁... 详细信息

为研究极端干旱对牧草生长的影响，选择多年生黑麦草（Lolium Perenne）(Lp)和雀麦（Bromus Valdivianus）(Bv)给予80%?85%植物有效水（Plant available water， PAW）和20%?25% PAW 2种水分处理，分析2牧草生长及体内水分状况对干旱胁迫的响应。研究表明：1)80%?85% PAW充足水分下，2牧草生物量积累、水势（Water potential， WP）、相对含水量（Relative water content， RWC）和净光合速率（net photosynthetic rate， Pn）无明显种间差异。Bv叶片宽而重、蒸腾速率（Transpiration rate， Tr）、CO2总导度(Total conductance to CO2， CndCO2)和气孔导度(Conductance to H2O， Gs)显著高于Lp。而Lp分蘗多、叶多汁；瞬时水分利用效率是Bv的1.63倍。2)20%?25% PAW对2牧草生长影响不完全一致，叶饱和重、干重和叶面积有相反变化趋势，但与充足水分相比差异不显著；Pn，Tr，CndCO2，Gs和RWC则极显著降低，WP极显著降低了1.60 MPa，致使枯叶占比和叶温差的显著升高。总之，雀麦和多年生黑麦草生长相近，水分利用模式不同；遭受极端干旱，不同种的2牧草耐旱机制具有一定的共性，通过增强叶片持水力、降低水分循环、减少蒸腾失水以提高牧草抗旱性。

关键词：干旱胁迫光合作用蒸腾作用生物量积累瞬时水分利用效率水势

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Concordance among pulse wave velocity assessment methods: A network meta-analysis

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中华医学杂志(英文版) 2024年第17期137卷 2137-2139页

作者： Cavero-Redondo iv.n Sequí-Domínguez Irene Saz-Lara Alicia Garcia-Klepzig Jose Luis Lucerón-Lucas-Torres Maribel Martínez-García Irene álvarez-Bueno Celia Martínez-Vizcaíno Vicente CarVasCare Research Group Facultad de Enfermería de Cuenca Universidad de Castilla-La Mancha Cuenca Spain Facultad de Ciencias de la Salud Universidad Autónoma de Chile Talca Chile Health and Social Research Center Universidad de Castilla-La Mancha Cuenca Spain Internal Medicine Department San Carlos University Hospital Madrid Spain Universidad Politécnica y Artística del Paraguay Asunción Paraguay

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Hydrogeochemical and isotopic assessment of the origin of nO_(3)^(−)and n-nH_(3)contents in the aquifer located in a closed lacustrine volcano-sedimentary basin in the metropolitan area of Mexico City

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Acta Geochimica 2024年第4期43卷 719-736页

作者： Jose iv.n Morales-Arredondo Maria Aurora Armienta Hernandez Joel Edmundo Ortega-Gutierrez Elisa Cuellar Ramirez natural Resources Department Institute of GeophysicsNational Autonomous University of MexicoCiudad Universitaria No.3000Col.Copilco UniversidadCoyoacán Delegation04360 MexicoCDMXMexico Instituto Politecnico nacional ***án 55La Laguna Ticoman07340 MexicoCDMXMexico Benemérita Universidad Autónoma de Puebla Ciudad Universitaria Col.San ManuelPueblaPueMexico

To explain the presence and spatial distribution of nO_(3)^(−)and n-nH_(3)in the Aquifer of the Metropolitan Area of Mexico City(AMAMC),a hydrogeochemical and isotopic analysis using^(13)C DIC(as well as the stable isotopes^(18)O and^(2)H)in groundwater was *** aquifer is located in an old closed lacustrine volcano-sedimentary basin;some wells hosted in the semi-confined zone contain high n-nH_(3)concentrations,while others present nO_(3)^(−)contents in the recharge zones(hosted in an oxidizing environment).In this study,a change in the isotopic signature(primarily in^(18)O and^(2)H)was observed from the recharge zones to the basin center in some of the wells with high nO_(3)^(−)concentrations,this behavior can be attributed to evaporation during the incorporation of recently infiltrated *** addition,the results for^(13)C(along with ^(2) H)in wells with the highest n-nH_(3)concentrations exhibited an atypically broad range of *** indicated the occurrence of hydrogeochemical and/or biochemical processes in the aquifer(in an oxidizing or reducing environment),such as organic degradation,bacterial decomposition(primarily in the ancient Lake Texcoco and which acts as a natural sink for carbon,nitrogen,sulfur,and phosphorus),besides rock weathering and dissolution,which may be responsible for a very marked isotopic modification of the^(13)C(and,to a lesser extent,2 H).Methanotrophic bacterial activity and methanogenic activity may be related to n-nH_(3)removal processes by oxidation and residual water incorporation respectively,whereas the increase in the nO_(3)^(−)content in some wells is due to the recent contribution of poor-quality water due to contamination.

关键词： 18 O and^(13)C isotopes Iron Hydrogeochemical processes nitrate nitrogen species

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Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

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Journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.guerra S.Castro-Lopes J.Matilla-Arias Idglan S.de Lima Edson C.Silva-Filho Josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

Coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) Coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

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