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Plant diversity and community structure of Brazilian Páramos

Journal of Mountain Science 2018年第6期15卷 1186-1198页

作者： Prímula Viana CAMPOS Pedro Manuel VILLA Jaquelina Alves NUNeS carlos e.g.r.schaefer Stefan POreMBSKI Andreza Viana NerI Federal University of Vicosa Department of Plant Biology Laboratory of Ecology and Evolution of Plants Campus Universitdrio 36570-900 Vicosa Minas Gerais Brazil Foundation for the Conservation of Biodiversity 7101 Merida Venezuela Minas gerais State University Rua dos estudantes 23 Santa Emilia 36800-000 Carangola Minas Gerais Brazil 4 Federal University of Vicosa Department of Soil Campus Universit（lrio 36570-900 Vicosa Minas Gerais Brazil 5 University of Rostock Institute of Bioseience Department of Botany Wismarsehe Str. 44/45 D-18051 Rostoek Germany

In eastern South America, high altitude grasslands represent a mountain system that has a high number of endemic species. However, studies on the ecology of plant communities in these environments remain scarce. We aimed to evaluate the patterns of biodiversity and structure of plant communities from rocky outcrops in high altitude grasslands of three areas at the Caparaó National Park, southeastern Brazil, by sampling 300 randomly distributed plots. Then, we compared the floristic composition, relative abundance, and biological and vegetation spectra among areas. We classified species as endemic and non-endemic and verified the occurrence of endangered species. Species richness was evaluated by rarefaction analysis on the sampling units. The importance value and species abundance distribution(SAD) models were assessed. We also performed an indicator species analysis. We sampled 58 species belonging to 49 genera and 32 families. The number of species decreased with increasing altitude, with significant differences being observed among areas regarding richness, abundance, and cover. Of the total number of species, 10 are endemic to the Caparaó National Park and 17 are listed on the Brazilian red List of endangered species. The dominant families on all peaks were Asteraceae and Poaceae. The SAD models showed lognormal and geometric distributions, corroborating the fact that 10 species that were common to all three areas were also the most dominant ones in the communities and showed the highest importance values, which ranged between 35% and 60%. Indicator species analysis revealed that 28 species(48.27%) were indicators. Of these, 42.85% had maximum specificity, meaning that they occurred only in one area. Thus, the number of species per life form ratio was similar among areas, yet vegetation spectra differed, especially for hemicryptophytes. The altimetric difference among the areas showed to be a very important driver in the community assembly, influencing the evalu

关键词： rock outcrops High altitude grasslands Species abundance distribution Species richness

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Soil and climate equally contribute to changes in the species compositions of Brazilian dry forests across 300 km

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Journal of Plant ecology 2020年第2期13卷 171-176页

作者： Daniel M.Arruda Luiz F.S.Magnago ricardo r.C.Solar reinaldo Duque-Brasil Priscyla M.S.rodrigues rubens M.Santos carlos e.g.r.schaefer Instituto de geociências Universidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil Centro de Formação em Ciências e Tecnologias Agroflorestais Universidade Federal do Sul da BahiaItabunaBahiaBrazil Instituto de Ciências Biológicas Universidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil Instituto de Ciências da Vida Universidade Federal de Juiz de ForaGovernador ValadaresMinas GeraisBrazil Colegiado de ecologia Universidade Federal do Vale do São FranciscoSenhor do BonfimBahiaBrazil Departamento de Ciências Florestais Universidade Federal de LavrasLavrasMinas GeraisBrazil Departamento de Solos Universidade Federal de ViçosaViçosaMinas GeraisBrazil

Aims Understanding the factors that control biodiversity distributions at different spatial scales has been a key challenge for conservation *** biodiversity,reflected in differences in species compositions among sites(beta diversity),can be derived from species replacement(turnover)and is driven by multiple ***,we sought to tackle this issue through two questions related to threatened Brazilian seasonally dry forests:(i)what is the contribution of species turnover to beta diversity?and(ii)which factors drive variations in species compositions among forest patches?Methods We sampled tree species and environmental variables(soils and climate)in 17 dry forest patches spaced almost 300 km *** used the beta diversity partitioning framework to determine the contribution of *** used redundancy analysis,with properly controlled spatial structure,to assess the contributions of the environmental and spatial factors to the variations of the species *** Findings Beta diversity among the patches was mainly represented by the turnover component(98.2%),with Simpson dissimilarity superior to other regions of the country(means of 0.89 and 0.71 in multiple site and pairwise measures,respectively).The environmental factors measured explained more than space,representing 30.3%of the variation of the species composition,of which 28.1%was nonspatially *** suggest that 300 km represents a threshold at which edaphic and climatic predictors have similar effects in determining community turnover(14.9%and 12.6%,respectively,without spatial structure).Thus,conservation strategies should be considered across landscapes to effectively protect tropical forest diversity,as even considering the different climatic aspects covered by the scale,landscaped edaphic varieties are important drivers of species turnover.

关键词： beta diversity environmental filter habitat fragmentation landscape structure phytogeography

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Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central Spain)

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Avian research 2024年第2期15卷 180-186页

作者： carlos Lazaro carlos Sanchez-garcía Fabian Casas e.Jorge Tizado Department of research Fundacion Artemisan13001 Ciudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain Department of Biodiversity and environmental Management Universidad de Leon24401 PonferradaSpain

Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their *** January 2021,a strong snowstorm known as‘Filomena’affected Spain,mainly the region of Madrid(Central Spain),which was fully covered with snow and suffered freezing temperatures for a *** bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),eurasian Magpie(Pica pica)and red-legged Partridge(Alectoris rufa).No significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by *** suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home *** results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species.

关键词： Alectoris rufa Climate change Cold spell Columba palumbus Migration Pica pica Winter

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Mortality rate after total knee arthroplasty or total hip arthroplasty in patients with a history of liver transplant

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World Journal of Orthopedics 2024年第4期15卷 310-311页

作者： e carlos rodriguez-Merchan Department of Orthopedic Surgery La Paz University Hospital-IdiPazMadrid 28046Spain

In this editorial I comment on the article by Ahmed et al published in a recent issue of the World J Orthop 2023;14:*** is well known that patients who have undergone a liver transplant(LT)may need to have a total hip arthroplasty(THA)or total knee arthroplasty(TKA)*** et al stated that the mortality rate in these patients was similar to the one of the general ***,there are three articles previously published that found higher mortality in LT patients who experienced THA/TKA than in the general population(individuals without LT).Therefore,in this editorial I would like to point out that there is controversy in the literature regarding whether LT patients undergoing THA/TKA have higher mortality than the general ***,future research should attempt to resolve this controversy.

关键词： Liver transplant Total knee arthroplasty Total hip arthroplasty results Mortality

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Mo_(2)P Monolayer as a Superior electrocatalyst for Urea Synthesis from Nitrogen and Carbon Dioxide Fixation:A Computational Study

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energy & environmental Materials 2024年第1期7卷 207-214页

作者： Dongxu Jiao Zhongxu Wang Yuejie Liu Qinghai Cai Jingxiang Zhao carlos r.Cabrera Zhongfang Chen College of Chemistry and Chemical engineering and Key Laboratory of Photonic and electronic Bandgap Materials Ministry of EducationHarbin Normal UniversityHarbin 150025China Modern experiment Center Harbin Normal UniversityHarbin 150025China Heilongjiang Province Collaborative Innovation Center of Cold region ecological Safety Harbin 150025China Department of Chemistry and Biochemistry The University of Texas at El PasoEl Paso TX 79968USA Department of Chemistry University of Puerto RicoRio Piedras CampusSan JuanPuerto Rico 00931USA

Urea synthesis through the simultaneous electrocatalytic reduction of N_(2)and CO_(2)molecules under ambient conditions holds great promises as a sustainable alternative to its industrial production,in which the development of stable,highly efficient,and highly selective catalysts to boost the chemisorption,activation,and coupling of inert N_(2)and CO_(2)molecules remains rather ***,by means of density functional theory computations,we proposed a new class of two-dimensional nanomaterials,namely,transition-metal phosphide monolayers(TM_(2)P,TM=Ti,Fe,Zr,Mo,and W),as the potential electrocatalysts for urea *** results showed that these TM_(2)P materials exhibit outstanding stability and excellent metallic ***,the Mo_(2)P monolayer was screened out as the best catalyst for urea synthesis due to its small kinetic energy barrier(0.35 eV)for C-N coupling,low limiting potential(-0.39 V),and significant suppressing effects on the competing side *** outstanding catalytic activity of the Mo_(2)P monolayer can be ascribed to its optimal adsorption strength with the key^(*)NCON species due to its moderate positive charges on the Mo active *** findings not only propose a novel catalyst with high-efficiency and high-selectivity for urea production but also further widen the potential applications of metal phosphides in electrocatalysis.

关键词： C-N coupling density functional theory Mo_(2)P monolayer urea synthesis

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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,Mexico

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Journal of Mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor SOTO carlos M.WeLSH r. Kenji YOSHIKAWA Hugo DeLgADO grANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and environmental research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of earth and environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

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Predicting intensive care unit-acquired weakness:A multilayer perceptron neural network approach

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World Journal of Clinical Cases 2024年第12期12卷 2023-2030页

作者： carlos Martin Ardila Daniel gonzález-Arroyave Mateo Zuluaga-gómez Department of Basic Sciences University of AntioquiaMedellín 52-59Colombia Department of Surgery Pontificia Universidad BolivarianaMedellín 0057Colombia Department of emergency Universidad Pontificia BolivarianaMedellín 0057Colombia

In this editorial,we comment on the article by Wang and Long,published in a recent issue of the World Journal of Clinical *** article addresses the challenge of predicting intensive care unit-acquired weakness(ICUAW),a neuromuscular disorder affecting critically ill patients,by employing a novel processing strategy based on repeated machine *** editorial presents a dataset comprising clinical,demographic,and laboratory variables from intensive care unit(ICU)patients and employs a multilayer perceptron neural network model to predict *** authors also performed a feature importance analysis to identify the most relevant risk factors for *** editorial contributes to the growing body of literature on predictive modeling in critical care,offering insights into the potential of machine learning approaches to improve patient outcomes and guide clinical decision-making in the ICU setting.

关键词： Intensive care units Intensive care unit-acquired weakness risk factors Machine learning Computer neural network

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How to fill the biodiversity data gap:Is it better to invest in fieldwork or curation?

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Plant Diversity 2024年第1期46卷 39-48页

作者： carlos A.Vargas Marius Bottin Tiina Sarkinen James e.richardson Marcela Celis Boris Villanueva Adriana Sanchez Programa de Biología Facultad de Ciencias NaturalesUniversidad del RosarioBogotaD.C.Colombia Subdireccion Científica Jardín Botanico de Bogota“Jose Celestino Mutis”BogotaD.C.Colombia Independent researcher BogotaD.C.Colombia Tropical Diversity Section Royal Botanic Garden EdinburghUK School of Biological Earth and Environmental SciencesUniversity College CorkCorkIreland Departamento de Química y Biología Universidad del NorteKm.5 Vía Puerto ColombiaArea Metropolitana de Barranquilla 081007Colombia

Data gaps and biases are two important issues that affect the quality of biodiversity information and downstream *** how best to fill existing gaps and account for biases is necessary to improve our current information most *** current main approaches for obtaining and improving data include(1)curation of biological collections,and(2)***,the comparative effectiveness of these approaches in improving biodiversity data remains little *** used the Flora de Bogota project to study the magnitude of change in species richness,spatial coverage,and sample coverage of plant records based on curation versus *** process of curation resulted in a decrease in species richness(synonym and error removal),but it significantly increased the number of records per *** contributed to a slight increase in species richness,via accumulation of new ***,curation led to increases in spatial coverage,species observed by locality,the number of plant records by species,and localities by species compared to ***,curationwas more efficient in producing new information compared to fieldwork,mainly because of the large number of records available in *** recommend intensive curatorial work as the first step in increasing biodiversity data quality and quantity,to identify bias and gaps at the regional scale that can then be targeted with *** stepwise strategy would enable fieldwork to be planned more costeffectively given the limited resources for biodiversity exploration and characterization.

关键词： Colombia Flora de Bogota Sample coverage Species richness Tropical Andes

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Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

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Frontiers of Computer Science 2024年第3期18卷 199-216页

作者： Antonio SANTOS-OLMO Luis enrique SÁNCHeZ David g.rOSADO Manuel A.SerrANO carlos BLANCO Haralambos MOUrATIDIS eduardo FerNÁNDeZ-MeDINA gSyA research group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data Science University of EssexColchester CO43SQUK Alarcos research group University of Castilla-La ManchaCiudad Real 13071Spain ISTr research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MArISMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several european and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management

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generation of lossy mode resonances(LMr)using perovskite nanofilms

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Opto-electronic Advances 2024年第2期7卷 33-40页

作者： Dayron Armas Ignacio r.Matias M.Carmen Lopez-gonzalez carlos ruiz Zamarreño Pablo Zubiate Ignacio del Villar Beatriz romero electrical Electronic and Communications Engineering DepartmentPublic University of NavarraPamplona 31006Spain Institute of Smart Cities(ISC) Public University of NavarraPamplona 31006Spain experimental Science and Technology School Rey Juan Carlos UniversityMostoles 28933Spain

The results presented here show for the first time the experimental demonstration of the fabrication of lossy mode resonance(LMr) devices based on perovskite coatings deposited on planar waveguides. Perovskite thin films have been obtained by means of the spin coating technique and their presence was confirmed by ellipsometry, scanning electron microscopy, and X-ray diffraction testing. The LMrs can be generated in a wide wavelength range and the experimental results agree with the theoretical simulations. Overall, this study highlights the potential of perovskite thin films for the development of novel LMr-based devices that can be used for environmental monitoring, industrial sensing, and gas detection, among other applications.

关键词： perovskite thin films slab waveguide lossy mode resonance

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