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Encroachment drives facilitation at alpine shrublines

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Forest Ecosystems 2024年第1期11卷 62-72页

作者： yafeng Wang Eryuan Liang j.julio Camarero College of Ecology and Environment Nanjing Forestry UniversityNanjing210037China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China Instituto Pirenaico de Ecología(IPE-CSIC) Zaragoza50080Spain

Ongoing encroachment is driving recent alpine shrubline dynamics globally,but the role of shrub-shrub interactions in shaping shrublines and their relationships with stem density changes remain poorly ***,the size and age of shrubs from 26 Salix shrubline populations along a 900-km latitudinal gradient(30°-38°N)were measured and mapped across the eastern Tibetan *** pattern analyses were used to quantify the spatial distribution patterns of juveniles and adults,and to assess spatial associations between *** intensity of univariate and bivariate spatial patterns was related to biotic and abiotic *** mark correlation functions with a quantitative mark(shrub height,basal stem diameter,crown width)were also employed to investigate the spatial relationships between shrub traits of juveniles and *** equation models were used to explore the relationships among conspecific interactions,patterns,shrub traits and recruitment dynamics under climate *** shrublines showed clustered patterns,suggesting the existence of conspecific *** patterns of juveniles and conspecific interactions(potentially facilitation)tended to intensify with increasing soil moisture *** warming before 2010 triggered positive effects on population interactions and spatial patterns via increased shrub ***,summer warming after2010 triggered negative effects on interactions through reduced shrub ***,shrub recruitment shifts under rapid climate change could impact spatial patterns,alter conspecific interactions and modify the direction and degree of shrublines responses to *** changes would have profound implications for the stability of alpine woody ecosystems.

关键词： Alpine shrubline Positive interactions Facilitation Spatial clustering Point pattern analyses

Malargüe Site Remediation:A Successful Solution for Uranium Mill Tailings

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原子能科学技术 2024年第10期58卷 2088-2094页

作者： BARARI E DíAZ j G GIOMIA KEMPF R A National Atomic Energy Commission Av.Del Libertador 8250Ciudad Autónoma de Buenos AiresC1429BNPArgentina

Comisión Nacional de Energía Atómica (CNEA) has the responsibility for restoring uranium mining facilities once the operations have ***,within its Environmental Program and in compliance with its legal responsibilities,decides to implement a restoration project for all sites related to the mining and processing of uranium *** Malargüe Site is located within the Province of Mendoza in the city of Malargü*** is the first site to successfully complete its *** activities consist of relocation of tailings to an engineering *** tailings management(encapsulation) and rehabilitation of the area was finished in june *** remediation alternative for the ore tailings was selected after conducting comparative studies and submitted the project to the society for *** objective of the encapsulation of the mineral tails is to isolate them from the environment,also proceeding with the decontamination and rehabilitation of the area (landscaping,post-closure monitoring and 20 years monitoring period).Encapsulation consisted of the construction of a containment cell for the mine tailings,to isolate them and prevent pollutants from entering the environment through the transfer *** clean the impacted areas,the soil was removed,it was incorporated into the encapsulation,and the filling was carried out with natural soils from the *** prevents radon transfer to the environment,as ^(222)Ra is an alpha emitter with a half-life of four days,which produces its own radioactive *** progeny are solids,and when a ^(222)Ra nucleus emits an alpha particle into the air,the resulting ^(218)Po nucleus,momentarily electrically charged,adheres to any dust *** prevents the discharge into the air containing radon and also containing dust particles charged with intensely radioactive radon *** tasks mentioned make it possible to decrease radon emanation,reduce radiological risks to the public and pre

关键词： remediation radionuclide transfer tailings encapsulation solution sustainable

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 407-424页

作者： M.SAFI M.VAKILIFARD M.j.MAHMOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of Mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COMSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian M.Mawby Bellamarie Ludwig Benjamin j.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane Fluidization Apparent density Carney flow

Developing a new agenda for increased food and climate security

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 35-54页

作者： William j.DAVIES Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUK

In many countries, political and environmental pressures are currently combining to generate a perfect storm of circumstances that is reducing food availability, increasing food costs and thereby reducing the availability of food to many. The UK is currently considering new national food and land management policies, and attention is also being given to legislation to address diet-related health issues. Many now argue for a revolution in UK farming practices to reduce their impact on the natural environment. The UK is not alone in facing these and other challenges. Both the contribution of agriculture to greenhouse gas(GHG) emissions and the effects of climate change on food production are issues receiving worldwide *** agricultural practices can result in greater C capture, reduced GHG emissions, enhanced soil quality and enhanced biodiversity. However, it is questioned if such farming systems will be productive enough to feed a growing population with the food required for social and health benefits. To fully exploit the impact of new plant science in farmer fields, it is imperative to effectively link science to farming practices and conduct a broader conversation around the food revolution with social scientists and with the general public.

关键词： Climate resilience food security human health planetary health regenerative agriculture

A three-dimensional model for the transportation of Fe and Mn in Arha Reservoir

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journal of Environmental Sciences 2000年第2期12卷 36-46页

作者： Xiao-hong, C. Brimicombe, a.j. Department of Geography Zhongshan University Guangzhou 510275 China

Coupling with a three dimensional (3D) hydrodynamic model and a suspended solids model, a 3D model for the transport of Fe and Mn in Arha Reservoir, China, was developed. The 3D velocity fields for the flood season are computed to drive the 3D model of Fe and Mn in which the processes of advection, diffusion, redox, sorption, desorption, deposition, and re suspension are included. The model has been calibrated by matching observed fluid, suspended solids, and total concentrations of Fe and Mn in the water column and in the sediment, successively. The model simulated both horizontal and vertical gradients of Fe and Mn in Arha Reservoir. It was found that Fe and especially Mn stratify in accordance with the stratification of DO during summer. The redox cycles across the water sediment interface has a principal role in the rise of Fe and Mn concentrations in the overlying water. It was also found that Fe and Mn loadings from the tributaries have a carryover effect on the water quality through a secondary contamination in the reservoir.

关键词： three dimensional model Fe Mn transport flow field Arha Reservoir CLC number: X1 Document code: A

Ab initio valence-space in-medium similarity renormalization group calculations for neutron-rich P,Cl,and K isotopes

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Chinese Physics C 2024年第7期48卷 181-190页

作者：谢萌冉沈留媛李健国李红蕙袁琪左维 Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Neutron-rich P,Cl,and K isotopes,particularly those with neutron numbers of approximately N=28,have attracted extensive experimental and theoretical *** utilize the ab initio valence-space in-medium similarity renormalization group approach,based on chiral nucleon-nucleon and three-nucleon forces,to investigate the exotic properties of these *** calculations of the low-lying spectra are performed.A key finding is the level inversion between 3/2_(1)^(+)and 1/2_(1)^(+)states in odd-A isotopes,attributed to the inversion ofπ0xod_(3/2) andπls_(1/2) single-particle *** ab initio calculations,which incorporate the three-nucleon forces,correlate closely with existing experimental *** calculations of effective proton single-particle energies provide deeper insights into the shell evolution for Z=14 and 16 *** results indicate that the three-body force plays important roles in the shell evolution for Z=14 and 16 sub-shells with neutron numbers ranging from 20 to ***,systematic ab initio calculations are conducted for the low-lying spectra of odd-odd *** results correspond with experimental data and provide new insights for future research into these isotopes up to and beyond the drip line.

关键词： ab initio calculations shell evolution low-lying spectra

Considerations for exerkine research focusing on the response to exercise training

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journal of Sport and Health Science 2024年第2期13卷 130-132页

作者： Ian a.j.Darragh Brendan Egan School of Health and Human Performance Dublin City UniversityGlasnevinDublin D09 V209Ireland Florida Institute for Human and Machine Cognition PensacolaFL 32502USA

García-Hermoso and colleagues1 recently published a systematic literature review and meta-analysis on exercise training-induced changes in exerkine concentrations in type 2diabetes mellitus patients,providing a contemporary view on how exerkines respond to exercise *** review prompted us to highlight 2 additional considerations that should be taken into account when studying the response of exerkines to exercise ***,whether exerkines can exhibit discordant responses to acute exercise compared to exercise training,and secondly,the need to consider the residual effects of the most recent exercise bout.

关键词： acute exercise prompt

Plant triterpenoid saponins function as susceptibility factors to promote the pathogenicity of Botrytis cinerea

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Molecular Plant 2024年第7期17卷 1073-1089页

作者： Francisco j.Escaray Amelia Felipo-Benavent Cristian j.Antonelli Begona Balaguer Maria Pilar Lopez-Gresa Pablo Vera Instituto de Biologia Molecular y Celular de Plantas Universidad Politecnica de Valencia-C.S.l.CCiudad Politecnica de la InnovacionEdificio 8Eacceso GIngeniero Fausto Elios/n46022ValenciaSpain

The gray mold fungus Botrytis cinerea is a necrotrophic pathogen that causes diseases in hundreds of plant species,including high-value *** polyxenous nature and pathogenic success are due to its ability to perceive host signals in its *** this study,we found that laticifer cells of Euphorbia lathyris are a source of susceptibility factors required by *** to cause ***,poor-in-latex(pil)mutants,which lack laticifer cells,show full resistance to this pathogen,whereas lot-of-latex mutants,which produce more laticifer cells,are *** S factors are triterpenoid saponins,which are widely distributed natural products of vast structural *** downregulation of laticifer-specific oxydosqualene cyclase genes,which encode the first committed step enzymes for triterpene and,therefore,saponin biosynthesis,conferred disease resistance to ***,the Medicago truncatula Iha-1 mutant,compromised in triterpenoid saponin biosynthesis,showed enhanced ***,the application of different purified triterpenoid saponins pharmacologically complemented the diseaseresistant phenotype ofpil and hla-1 mutants and enhanced disease susceptibility in different plant *** found that triterpenoid saponins function as plant cues that signal transcriptional reprogramming in ***,leading to a change in its growth habit and infection strategy,culminating in the abundant formation of infection cushions,the multicellular appressoria apparatus dedicated to plant penetration and biomass destruction in *** together,these results provide an explanation for how plant triterpenoid saponins function as disease susceptibility factors to promote *** pathogenicity.

关键词： Euphorbia lathyris laticifer cell latex appressorium infection cushion necrotrophic fungi