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Tribologically induced nanostructural evolution of carbon materials: A new perspective

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Friction 2024年第1期12卷 144-163页

作者： Guilherme Oliveira neves Nicolás ARAYA Diego Berti SALVARO Thiago de souza LAMIM Renan Oss GIACOMELLI Cristiano BINDER Aloisio Nelmo KLEIN JoséDaniel Biasoli de MELLO Laboratório de Materiais Universidade Federal de Santa CatarinaSanta Catarina 88040-900Brazil Departamento de Ingeniería Mecánica Facultad de IngenieríaUniversidad del Bío-BíoConcepcion 4070-386Chile Universidad de Concepción Concepcion 4070-386Chile SENAI Innovation Institute for Laser Processing Santa Catarina 89218-153Brazil Universidade Federal de Uberlândia Minas Gerais 38408-100Brazil

Carbon-based solid lubricants are excellent options to reduce friction and wear,especially with the carbon capability to adopt different allotropes *** the macroscale,these materials are sheared on the contact along with debris and contaminants to form tribolayers that govern the tribosystem *** a recently developed advanced Raman analysis on the tribolayers,it was possible to quantify the contactinduced defects in the crystalline structure of a wide range of allotropes of carbon-based solid lubricants,from graphite and carbide-derived carbon particles to multi-layer graphene and carbon *** addition,these materials were tested under various dry sliding conditions,with different geometries,topographies,and solid-lubricant application *** of the initial tribosystem conditions and allotrope level of atomic ordering,there is a remarkable trend of increasing the point and line defects density until a specific saturation limit in the same order of magnitude for all the materials tested.

关键词： carbon nanostructures tribology Raman spectroscopy defects quantification tribolayer solid lubrication

Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients

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Journal of Sport and Health Science 2024年第4期13卷 548-558,F0003页

作者： Hugo de Luca Correa Lysleine Alves Deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos neves Andrea Lucena Reis Thais Branquinho de Araujo Carmen Tzanno-Martins Fernanda Silveira Tavares Luiz Sinesio Silva Neto Claudio Avelino Rodrigues Santos Paolo Lucas Rodrigues-Silva Fernando Honorato souza Vitoria Marra da Motta Vilalva Mestrinho Rafael Lavarini dos Santos Rosangela Vieira Andrade Jonato Prestes Thiago dos Santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance Mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil Department of Medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of Medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Background:Hemodialysis(HD) per se is a risk factor for *** the growing body of evidence on blood-flow restriction(BFR) exercise in HD patients,identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training *** aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise(RE) with BFR on this ***:Two hundred and six HD patients volunteered for this study(all with a glomerular filtration rate of 70 years old),and HD ***,RE+BFR significantly increases D-dimer after 4 *** with borderline baseline D-dimer levels(400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range(≥500 ng/mL).Conclusion:These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE+BFR.D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE+BFR.

关键词： Blood-flow restriction Chronic kidney disease Coagulation Hemodialysis Vascular occlusion exercises

Response to Commentary by Dr. Matthew J. Clarkson on

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Journal of Sport and Health Science 2024年第5期13卷 670-671页

作者： Hugo de Luca Corrêa Lysleine Alves Deus Dahan da Cunha Nascimento Nicholas Rolnick Rodrigo Vanerson Passos neves Andrea Lucena Reis Thais Branquinho de Araújo Carmen Tzanno-Martins Fernanda Silveira Tavares Luiz Sinésio Silva Neto Cláudio Avelino Rodrigues Santos Paolo Lucas Rodrigues-Silva Fernando Honorato souza Vitória Marra da Motta Vilalva Mestrinho Rafael Lavarini dos Santos Rosangela Vieira Andrade Jonato Prestes Thiago dos Santos Rosa Post-graduate Program of Physical Education Catholic University of BrasıliaBrasılia 71966-700Brazil The Human Performance Mechanic Lehman CollegeNew YorkNY 10011USA Clinical Group Home Dialysis Center and RenalClass Sao Paulo 01239-040Brazil Department of Medicine Catholic University of BrasıliaBrasılia 71966-700Brazil Faculty of Medicine Federal University of TocantinsTocantins 77001-090Brazil Embrapa Genetic Resources and Biotechnology Brasılia 70770-917Brazil g Graduate Program of Genomic Sciences and Biotechnology Brasılia 71966-700Brazil

Dear editor:We sincerely thank Matthew *** for his insightful commentary1 on our recent publication in the Journal of Sport and Health Science.2 Clarkson's pioneering work in the development and application of blood flow restriction (BFR) exercise protocols has undeniably laid the groundwork for subsequent investigations in this field,including our own.(3-6)His commentary not only highlights the relevance and timeliness of our study but also offers valuable perspectives on refining safety considerations for intradialytic BFR exercise among hemodialysis patients.

关键词： patients application flow

Differential effects of two dominant plant species on community structure and invasibility in an old-field ecosystem

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Journal of Plant Ecology 2011年第3期4卷 123-131页

作者： lara souza Jake F.Weltzin Nathan J.Sanders Department of Ecology and Evolutionary Biology University of Tennessee1416 Circle DriveKnoxvilleTN 37996USA USA National Phenology Network National Coordinating Office1955 East 6th StreetTucsonAZ 85719USA

Aims In this study,we examined the effects of Solidago altissima(hereafter Solidago)and two species in the genus Verbesina,Verbesina virginica and Verbesina occidentalis(hereafter Verbesina),on the structure of an old-field plant community and establishment by an invasive plant species,Lespedeza cuneata(hereafter Lespedeza).Methods We removed Solidago,Verbesina and both Solidago and Verbesina from 4m^(-2)plots in an intact old-field community during two growing *** then quantified the effects of these removals on richness,evenness,diversity and composition of the subdominant plant *** also measured the total aboveground biomass and the aboveground biomass of the subdominant *** assess how these removals affected establishment by Lespedeza,we planted 20 seeds in each plot and tracked seedling emergence and survival for one growing *** Findings Subdominant community evenness and Shannon diversity were higher in plots from which Solidago and Verbesina were removed relative to control ***,there were no effects of dominant species removal on species richness or composition of the subdominant *** aboveground biomass was not affected by dominant species removal,suggesting that the community of subdominant species exhibited *** fact,subdominant community biomass was greater when Solidago,but not Verbesina,was *** availability was also greater in plots where Solidago was removed relative to control plots throughout the growing *** addition,removal of dominant species,in particular Solidago,indirectly reduced the emergence,but not survival,of Lespedeza seedlings by directly promoting subdominant community *** together,our results suggest that dominant old-field plant species affect subdominant community structure and indirectly promote establishment by Lespedeza.

关键词： compensation establishment invasive Lespedeza cuneata Solidago Verbesina

Tritrichomonas foetus:New structures by high-resolution scanning helium ion microscopy

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BIOCELL 2021年第2期45卷 259-266页

作者： MARLENE BENCHIMOL ABIGAIL MIRANDA-MAGALHÃES ANTONIO PEREIRA-neves WANDERLEY DE souza Universidade do Grande Rio Duque de Caxias25071-202Rio de Janeiro Departamento de Microbiologia Laboratório de Biologia Celular de PatógenosFiocruzInstituto Aggeu MagalhãesRecife52060-269Brazil Universidade Federal do Rio de Janeiro Instituto de Biofísica Carlos Chagas FilhoLaboratório de Ultraestrutura Celular Hertha Meyer Instituto Nacional de Ciência e Tecnologia(INBEB)and Centro Nacional de Biologia Estrutural e Bioimagens(CENABIO)Rio de Janeiro21941-902Brazil

Helium ion scanning microscopy(HIM)is a novel high-resolution scanning microscopy technique that uses helium ions instead of electrons to form images of the highest quality and resolution,providing a sub-nanometer resolution sputter uncoated biological ***,we took advantage of HIM to explore the cell surface of Tritrichomonas foetus,a protist parasite of cattle that provokes hard infection and abortion in *** describe thin protrusions,like nanotubes described in other cells,with different sizes(27 nm to 81 nm in thickness)and various lengths(from 73 nm to 2μm),as well bulbous structures either budding from the cell surface or present in the extremities of some *** flagella also presented these thin protrusions and different protein decoration,similar to those previously described using freeze-fracture *** between two cells were also seen,and their role in infection is *** cell surface was also examined and showed several pits indicative of endocytic activity and other types of arrays of *** observations were confirmed using Scanning Electron Microscopy(SEM),negative staining,and conventional thin sectioning for observation by transmission electron *** findings provide new and relevant information that may contribute to a better understanding of protozoan biology and its interaction with mammalian cells.

关键词： Nanotubes Microvesicles Surface specializations

CO_(2)enrichment accelerates successional development of an understory plant community

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Journal of Plant Ecology 2010年第1期3卷 33-39页

作者： lara souza R.Travis Belote Paul Kardol Jake F.Weltzin Richard J.Norby Environmental Sciences Division Oak Ridge National LaboratoryBuilding 1062PO Box 2008Oak RidgeTN 37831USA Department of Ecology and Evolutionary Biology 569 Dabney HallUniversity of TennesseeKnoxvilleTN 37996USA The Wilderness Society 503 West Mendenhall St BozemanMT 59715USA USA National Phenology Network National Coordinating officeTucsonAZ 85721USA

Aims Rising concentrations of atmospheric carbon dioxide([CO_(2)])may influence forest successional development and species composition of understory plant communities by altering biomass production of plant species of functional ***,we describe how elevated[CO_(2)](eCO_(2))affects aboveground biomass within the understory community of a temperate deciduous forest at the Oak Ridge National Laboratory sweetgum(Liquidambar styraciflua)free-air carbon dioxide enrichment(FACE)facility in eastern Tennessee,*** asked if(i)CO_(2)enrichment affected total understory biomass and(ii)whether total biomass responses could be explained by changes in understory species composition or changes in relative abundance of functional groups through *** and methods The FACE experiment started in 1998 with three rings receiving ambient[CO_(2)](aCO_(2))and two rings receiving eCO_(2).From 2001 to 2003,we estimated species-specific,woody versus herbaceous and total aboveground biomass by harvesting four 130.5-m subplots within the established understory plant community in each FACE *** 2008,we estimated herbaceous biomass as previously but used allometric relationships to estimate woody biomass across two 535-m quadrats in each FACE *** findings Across years,aboveground biomass of the understory community was on average 25%greater in eCO_(2)than in aCO_(2)*** could not detect differences in plant species composition between aCO_(2)and eCO_(2)***,we did observe shifts in the relative abundance of plant functional groups,which reflect important structural changes in the understory *** 2001-03,little of the understory biomass was in woody species;herbaceous species made up 94%of the total understory biomass across[CO_(2)]*** time,woody species increased in importance,mostly in eCO_(2),and in 2008,the contribution of herbaceous species to total understory biomass was 61%in aCO_(2)and only 33%in eCO_(2)***

关键词： community composition FACE aboveground biomass woody herbaceous sweetgum Microstegium vimineum Lonicera japonica

Surface runoff and soil erosion in a natural regeneration area of the Brazilian Cerrado

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International Soil and Water Conservation Research 2020年第2期8卷 124-130页

作者： Karina dos Santos Falcao Elói Panachuki Felipe das neves Monteiro Roniedison da Silva Menezes Dulce B.B.Rodrigues Jullian souza Sone Paulo Tarso S.Oliveira Department of Agronomy State University of Mato Grosso do SulAgronomy DepartmentAquidauanaMS79200-000Brazil Federal University of Mato Grosso do Sul CxP 549Campo GrandeMS79070-900Brazil Department of Hydraulics and Sanitation Sao Carlos School of EngineeringUniversity of Sao PauloCxP.359Sao CarlosSP13566-590Brazil

The Brazilian Cerrado has been converted to farmland,and there is little evidence that this expansion will decrease,mainly because agriculture is the country's main economic ***,the impacts of intense modification of land use and land cover on surface runoff and soil erosion are still poorly un-derstood in this ***,we assessed surface runoff and soil loss in a woodland Cerrado area under a former pasture area,which was abandoned and has undergone a natural regeneration process for 7 years(RC).Its results were compared with that found in an undisturbed area of woodland Cerrado(CE),40-month-old eucalyptus(3.0×1.8 m)(EU),and pasture under rotational grazing(PA).The study was conducted on Red Acrisol located in the Brazilian *** performed rainfall simulations on a plot of 0.7 m2 and using three constant rainfall intensities of 60,90,and 120 mm h-1 for 1 *** each rainfall intensity,we carried out four repetitions using different plots in each treatment,i.e.12 plots per treat-ment studied and 48 plots in *** noted that the soil physical properties were improved in RC and,consequently,water infiltration and soil erosion control;RC presented surface runoff and soil loss different from EU and PA(a=0.05).The macroporosity and soil bulk density affected surface runoff in RC and PA because the RC was used as pasture and is currently regenerating back to the cerrado *** the rainfall intensity increased,EU became more similar to PA,which showed the highest surface runoff and soil *** findings indicate that natural regeneration processes(pasture to the cerrado vegetation)tend to improve the soil ecosystem services,improving infiltration and reducing surface runoff and soil erosion.

关键词： Cerrado deforestation Forest regeneration Soil erosion

Ecological intensification of cropping systems enhances soil functions,mitigates soil erosion,and promotes crop resilience to dry spells in the Brazilian Cerrado

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International Soil and Water Conservation Research 2021年第4期9卷 591-604页

作者： Lucas de Castro Moreira da Silva Junior Cesar Avanzi Devison souza Peixoto Marina neves Merlo Emerson Borghi Alvaro Vilela de Resende Salvador Francisco Acuna-Guzman Bruno Montoani Silva Department of Soil Science Federal University of Lavras(UFLA)37200-900LavrasMGBrazil Department of Water Resources Federal University of Lavras(UFLA)37200-900LavrasMGBrazil Embrapa Maize and Sorghum Brazilian Agricultural Research Corporation(EMBRAPA)PO Box:28535701-970Sete LagoasMGBrazil Department of Physics Federal University of Lavras(UFLA)37200-900LavrasMGBrazil Center for Engineering and Industrial Development(CIDESI) Pie de la Cuesta 702Desarrollo San PabloQuerétaroQro.76125Mexico

Water scarcity threatens global food security and agricultural systems are challenged to achieve high yields while optimizing water *** deficit can be accentuated by soil physical degradation,which also triggers water losses through runoff and consequently soil *** soil health in cropping systems within the Brazilian Cerrado biome have been surveyed throughout the years,information about soil erosion impacts and its mitigation are still not well understood;especially concerning the role of cropping system diversification and its effects on crop ***,the aim of this study was to assess whether ecological intensification of cropping systems-inclusion of a consorted perennial grass and crop rotation-could promote soil coverage and consequently decrease water erosion and soil,water,and nutrient *** work studied the effects of crop rotation and consorted Brachiaria,along with different levels of investment in fertilization on soil physical quality and on soil,water,and nutrient losses,and crop *** proved that soybean monoculture(SS)is a system of low sustainability even under no-till in the Brazilian Cerrado *** exhibited high susceptibility to soil,water,and nutrient losses,causing low crop *** results showed that water losses in SS cropping system were approximately 10%of the total annual rainfall,and total K losses would require an additional 35%of K ***,ecological intensification of cropping systems resulted in enhanced soil environmental and agronomic functions,increased grain yield,and promoted soil and water conservation:high soil cover rate,and low soil,water and nutrient *** intensification proved to be an adequate practice to boost crop resilience to water deficit in the Brazilian Cerrado.

关键词： Crop rotation Grain production Nutrient losses Soil physical quality Tropical region

Vegetation structure and edaphic factors in veredas reflect different conservation status in these threatened areas

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Forest Ecosystems 2022年第3期9卷 387-395页

作者： Yule Roberta Ferreira Nunes Camila Silveira souza Islaine Francielly Pinheiro de Azevedo Odirlei Simôes de Oliveira Leidivan Almeida Frazão Rúbia Santos Fonseca Rubens Manoel dos Santos Walter Viana neves Programa de Pós-Graduaçao Em Botânica Aplicada Departamento de Biologia GeralUniversidade Estadual de Montes ClarosAvenida Dr.Ruy BragaS/N-Bairro Vila MauricéiaMontes ClarosMinas Gerais39401-089Brazil Laboratório de Ecologia Vegetal Universidade Estadual de Montes ClarosAvenida Dr.Ruy BragaS/N-Bairro Vila MauricéiaMontes ClarosMinas Gerais39401-089Brazil Instituto de Ciências Agrarias-Universidade Federal de Minas Gerais Avenida Universitária1.000-Bairro Universit�arioMontes ClarosMinas Gerais39404-547Brazil Departamento de Ciências Florestais Universidade Federal de LavrasCP 3037LavrasMinas Gerais37200-000Brazil Instituto Mineiro de Gestao dasÁguas Secretaria de Estado de Meio Ambiente e Desenvolvimento SustentávelAvenida JoséCorreia Machado900-Bairro IbiturunaMontes ClarosMinas Gerais39401-832Brazil

Background:In Cerrado humid areas,veredas are considered as hygrophilous communities,marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter *** in veredas ecosystems due to drought and changes in the water table,which represent important areas for biodiversity maintenance in the Brazilian cerrado,can lead to the emergence of new landscapes and *** that the veredas are changed in species composition due to anthropogenic factors,in this study,we evaluated the flora composition and described the current vegetation profile of two veredas under different disturbances levels that are located in the north of Minas Gerais State,***:Altogether,2,268 individuals of 91 species belonging to 36 families were *** results demonstrated that the studied veredas were floristically different in terms of the arboreous-shrubby species composition,richness,and *** the hygrophilous forest formations and open areas in the two veredas present typical species from these environments(same species with high importance values),the drought in the water table caused an expansion of Cerrado species in the open areas and in the hygrophilous ***,in the hygrophilous forest there was an increase in the abundance of species that occur in less saturated ***:Our results demonstrate that the studied veredas are changing in species composition due to anthropogenic factors which leads to the drought of these formations(water balance effect).These anthropogenic effects cause a modification with the expansion and increase in the abundance of typical species of other areas of Cerrado and resistant to less saturated soils,leading to the veredas ***,future studies should investigate other veredas on a broader scale to detect changes in the water table that lead to a consequent change in vegetation *** this way,we will have support for the conscientious management and conservatio

关键词： Cerrado Conservation Palm swamp Plant distribution Climate change Water balance effect Vereda drought Phytosociological analysis