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材料科学与工程（中英文B版） 2020年第4期10卷 134-138页

作者： Mayara Fernanda Pereira Bruno Souza Abrão Rhander Viana rosemar batista da silva School of Mechanical Engineering Federal University of UberlândiaAv.João Naves deÁvila2121UberlândiaMGCEP 38408-100Brazil University of Brasilia GamaBrasília-DFCEP 72444-240Brazil

In precision machining processes such as grinding,for example,analysis of machined surface is important one of most parameters to evaluate process *** important is to perform tribological analysis to understand chip formation and abrasive wheel wear,thus enabling manufacturing of components free of thermal *** grinding,due to high hardness of abrasive grains that remove material from workpiece in chip form and very low values of radial depth of cut,combination of low roughness values and tight dimensional tolerances is ***,the parameters involved in this process are determinant in surface quality that is primarily evaluated in terms of surface roughness and workpiece *** this work,surface roughness(Rt parameter)and scanning electron microscope(SEM)images of ground surfaces of the AISI 420 martensitic stainless steel samples were *** were carried out in surface grinding with a white aluminum oxide wheel and an environmentally-friendly semisynthetic water-soluble *** values of radial depth of cut(10μm and 25μm)were *** results showed that the highest roughness values,deeper grooves on the machined surfaces as well as poorer surface quality were obtained after grinding under the severest cutting conditions.

关键词： Grinding AISI 420 martensitic stainless steel trigological analysis depth of cut surface roughness SEM images

Surface Finish Evaluation of AISI P100 Steel after Grinding with MQL Technique with Different Flow Rates

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Journal of Mechanics Engineering and Automation 2020年第2期10卷 60-65页

作者： Bruno Souza Abrão Mayara Fernanda Pereira Cleudes Guimarães Lurian Souza Vieira da silva Rodrigo deSouza Ruzzi rosemar batista da silva Eduardo Carlos Bianchi Alisson Rocha Machado School of Mechanical Federal University of UberlandiaUberlandia/MGCEP 38.408-208Brazil School of Engineering São Paulo State UniversityBauru/SPCEP 17.033-360Brazil Mechanical Engineering Graduate Program Pontifícia Universidade Católica do Paraná(PUC-PR)R.Imaculada Conceição1155Bairro Prado VelhoCEP 80215-901Curitiba/PRBrazil

Grinding operation is a finishing process often employed when high precision and narrow geometric tolerances are *** requirements can be achieved only if cutting conditions are properly selected,especially the cooling-lubrication *** general,grinding is performed in presence of cutting fluid,however,due to the environmental impacts and costs of the conventional coolant delivery technique(flow rates from 4 L/min to 300 L/min),alternative cooling-lubrication techniques have been developed on restriction of the coolants *** the several techniques,MQL(minimum quantity of lubricant)technique has received special attention from machining users because of its advantages in terms of surface quality of workpiece and drastic reduction in use of *** this context,this paper evaluated the performance of the MQL technique as compared to the flood coolant in peripheral surface grinding of AISI P100(VP100)steel with conventional aluminum oxide grinding wheel in relation to the surface roughness(Ra and Rz).Input parameters tested were equivalent chip thickness(0.09μm,0.18μm and 0.27μm)and flow rate of the cutting fluid(60 mL/h,150 mL/h and 240 mL/h)of the MQL *** showed that the grinding with MQL technique provided lower surface roughness values compared to conventional flood cooling,especially when machining under the intermediary cutting ***,with exception of heq of 0.09 m,the MQL technique resulted in lower values of Rz parameter as compared to the conventional coolant technique,regardless of the flow rate tested.

关键词： Grinding AISI P100 steel MQL technique equivalent chip thickness surface roughness

Litter removal impacts on soil biodiversity and eucalypt plantation development in the seasonal tropics

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Journal of Forestry Research 2023年第3期34卷 735-748页

作者： Jonas Inkotte Barbara Bomfim Sarah Camelo da silva Marco Bruno Xavier Valadão Márcio Gonçalves da Rosa Roberta batista Viana Alcides Gatto Reginaldo SPereira Department of Forestry Engineering University of BrasiliaBrasíliaDistrito FederalBrazil Climate and Ecosystem Sciences Division Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA SESI/SENAI Social Service Industry Santa Catarina StateChapecóBrazil

The little layer of tree plantations provides primary nutrients for uptake,buff ers changes in soil moisture,and provides habitat and substrate to soil epigeic ***,this layer in eucalypt plantations is often removed to reduce fuel load during the fi re season in the Brazilian savanna(Cerrado).Therefore,it is necessary to quantify the eff ects of changes in litter dynamics on the function of these plantations,on key nutrient cycling processes and on epigeic fauna diversity and *** two adjacent stands(one juvenile and one mature),the consequences of two years of litter removal were quantifi ed as monthly litterfall,leaf and fi ne wood litter decomposition,epigeic fauna abundance and diversity,soil biogeochemical variables,and tree diameter and basal area *** litterfall rates in juvenile and mature stands did not change with litter removal over the study *** litterfall ranged from 4.1 to 4.9 Mg ha^(−1)a^(−1)in litter removal plots and from 3.9 to 4.8 Mg ha^(−1)a^(−1)in control *** wood litter decomposition was slower in litter removal plots compared to controls,while leaf decomposition rates were similar in *** years of litter removal in the juvenile stand did not aff ect topsoil biogeochemical parameters but decreased available phosphorus at 20–40 cm depth relative to *** the mature stand,total cation exchange capacity(0–20 cm)was higher in controls(6.4 cmol c dm^(−3))relative to litter removal plots(6.3 cmol c dm^(−3)),while soil moisture(0–40 cm depth)was lower in litter removal(25.45 m 3 m^(−3))compared to control plots(26 m^(3)m^(−3))in the dry season.A non-metric multidimensional scaling ordination revealed an increased homogeneity in epigeic fauna where litter was ***,decomposition,diameter increment,four soil physical parameters and fourteen chemical parameters at 0–20 and 20–40 cm depth explained the diff erences in soil epigeic fauna composition between litter removal and control p

关键词： Cerrado Nutrient cycling Soil ecology Soil epigeic fauna Plantation management

Entropy model to assess sediment resuspension probability and trap efficiency of small dams

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International Journal of Sediment Research 2022年第5期37卷 675-686页

作者： Francisco Jairo Soares Pereira Antonio Viana da silva Filho José Wellington batista Lopes José Carlos de Araújo Department of Agricultural Engineering Federal University of Ceará Campus Do Pici Rural Federal University of Pernambuco Federal University of Piauí

In the Brazilian drylands, there are tens of thousands of small dams. Despite their paramount importance to the rural population, they are rarely monitored. Water demand increases with time while, simultaneously, siltation reduces reservoir water capacity and availability. Reservoir siltation models are, therefore, mandatory to manage the numerous ungauged small dams in these *** objective of the current study is to improve sediment trap efficiency(TE) modeling by including resuspension as a key probabilistic process. The Shannon entropy was used to estimate the sediment resuspension probability, which was merged with the Camp model and generated the RETSED entropy model. To validate the RETSED model, an experimental check dam(ECD, 300 m3), located in the Gilbu es desertification site, Brazil, was monitored hourly during one hydrological year(July 2018-July 2019). Measurements show that the annual volumetric decline of the check dam was 12%; and that the average trap efficiency equaled 86%. Only 9.5% of the hourly sediment concentration outflow exceeded the average plus one standard deviation, showing that the reservoir is well mixed; a fact which highlights the relevance of the resuspension process. Three empirical models failed to mimic the experimental results: Churchill(TE = 99%), Brune(TE = 75%), and Maryland(TE = 94%). According to the RETSED entropy model, the resuspension probability during the experiment was 10%and TE = 81%, a value only 6% below the measured one. The Camp model simulated TE = 89%, only 3%higher than the measured value, but confirmed the Camp model’s tendency to overestimate TE due to a disregard of resuspension. The deterministic model showed low sensitivity concerning the hydrodynamic effects, whereas the entropy formulation proved to be more consistent with physical behavior: the resuspension probability clearly increased and trap efficiency decreased with rising reservoir discharge.

关键词： Erosion Check dam Sedimentation Ungauged basins Camp model

Engineering Improved Photosynthesis in the Era of Synthetic Biology

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Plant Communications 2020年第2期1卷 1-17页

作者： Willian batista-silva Paula da Fonseca-Pereira Auxiliadora Oliveira Martins Agustin Zsogon Adriano Nunes-Nesi Wagner L.Araujo Departamento de Biologia Vegetal Universidade Federal de Vic¸osaVic¸osaMinas Gerais 36570-900Brazil

Much attention has been given to the enhancement of photosynthesis as a strategy for the optimization of crop *** traditional plant breeding is most likely reaching a plateau,there is a timely need to accelerate improvements in photosynthetic efficiency by means of novel tools and biotechnological *** emerging field of synthetic biology offers the potential for building completely novel pathways in predictable directions and,thus,addresses the global requirements for higher yields expected to occur in the 21st ***,we discuss recent advances and current challenges of engineering improved photosynthesis in the era of synthetic biology toward optimized utilization of solar energy and carbon sources to optimize the production of food,fiber,and fuel.

关键词： photosynthesis synthetic biology genetic engineering yield improvement targeted manipulation

The role of rhizobacteria in rice plants: Growth and mitigation of toxicity

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Journal of Integrative Agriculture 2018年第12期17卷 2636-2647页

作者： Marcela C F Rêgo Aline F Cardoso Thayná da C Ferreira Marta C C de Filippi Telma F V batista Rafael G Viana Gisele B da silva Plant Protection Laboratory Institute of Agrarian Sciences Federal Rural University of Amazon Phytopathology Laboratory Brazilian Enterprise for Agricultural Research-Rice and Beans

Allelopathic compounds reduce the growth and productivity of upland rice plants, especially in consecutive plantations. The rhizobacteria Pseudomonas fluorescens BRM-32111 and Burkholderia pyrrocinia BRM-32113 have been recorded as growth promoters in rice. This study was developed to understand the effect of the application of rhizobacteria on upland rice plants in consecutive plantations. Experiments were conducted in a completely randomized design with four replications of four treatments: rice seed inoculated with P. fluorescens BRM-32111, rice seed inoculated with B. pyrrocinia BRM-32113(both sown on soil with rice residue), non-inoculated plants sown on soil with rice residue(control with residue(WR)), and non-inoculated plants on soil with no residue(NR). Roots and seedling growth were adversely affected by allelopathic compounds in control WR plants. Plants inoculated with rhizobacteria P. fluorescens BRM-32111 or B. pyrrocinia BRM-32113 induced an increase of 88% in biomass, 3% in the leaf area, 40% in length, 67% in root biomass, 21% in chlorophyll a, 53% in chlorophyll(a+b), 50% in rate of carbon assimilation(A), 227% in A/rubisco carboxylation efficiency(Ci) and 63% in water use efficiency(WUE) compared to control WR plants. These results indicate that rhizobacteria P. fluorescens BRM-32111 and B. pyrrocinia BRM-32113 increase the tolerance of rice plants to stress from allelochemicals. There are possible practical agricultural applications of these results for mitigating the effects of environmental allelochemistry on upland rice.

关键词： allelopathy B.pyrrocinia P.fluorescens rhizobacteria rice

The role of pro-inflammatory components, carcinoma-associated fibroblasts, and tumorassociated macrophages in ovarian cancer progression and metastasis

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Journal of Cancer Metastasis and Treatment 2023年第1期9卷 385-398页

作者： Josiany Carlos de Souza Roberto silva Ribeiro Junior Tatiana Massariol Pimenta Bárbara da silva Martins Leticia batista Azevedo Rangel Postgraduate Program in Biotechnology/RENORBIO Health Sciences CenterFederal University of Espirito SantoVitória 29047-105Brazil Department of Pharmaceutical Sciences Health Sciences CenterFederal University of Espirito SantoVitória 29047-105Brazil Biochemistry Program Health Sciences CenterFederal University of Espirito SantoVitória 29047-105Brazil

Ovarian cancer(OC)is associated with poor outcomes and challenges scientists and *** is usually diagnosed in advanced stages when it is frequently aggressive,chemoresistant,and *** most prevalent form of OC is epithelial ovarian cancer(EOC),which displays significant heterogeneity,enhancing the difficulty in managing the *** factors have been associated with the disease’s development and progression,especially those related to the tumor microenvironment(TME).Here,we highlight components of the ovarian TME in the disease development process,including pro-inflammatory pathways activated by interleukins,cytokines and chemokines,cancer-associated fibroblasts,tumor-associated macrophages,and epithelial-mesenchymal *** compiled evidence identifying TME factors promoting the development,chemoresistance,and metastasis,including cytokines,chemokines,growth factors,and tumor-associated *** identify potential targets for treatment and improving *** targets block or alter pathways associated with OC(especially EOC)progression.

关键词： CAFs interleukins ovarian cancer TAMs tumor microenvironment

High-throughput phenotyping of two plant-size traits of Eucalyptus species using neural networks

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Journal of Forestry Research 2022年第2期33卷 591-599页

作者： Marcus Vinicius Vieira Borges Janielle de Oliveira Garcia Tays silva batista Alexsandra Nogueira Martins silva Fabio Henrique Rojo Baio Carlos Antônio da silva Junior Gileno Brito de Azevedo Glauce Taís de Oliveira Sousa Azevedo Larissa Pereira Ribeiro Teodoro Paulo Eduardo Teodoro Federal University of Mato Grosso Do Sul(UFMS) Chapadão Do SulMato Grosso Do Sul 79560000Brazil Department of Geography State University of Mato Grosso(UNEMAT)SinopMato Grosso 78555000Brazil

In forest modeling to estimate the volume of wood,artificial intelligence has been shown to be quite effi-cient,especially using artificial neural networks(ANNs).Here we tested whether diameter at breast height(DBH)and the total plant height(Ht)of eucalyptus can be pre-dicted at the stand level using spectral bands measured by an unmanned aerial vehicle(UAV)multispectral sensor and vegetation *** do so,using the data obtained by the UAV as input variables,we tested different configurations(number of hidden layers and number of neurons in each layer)of ANNs for predicting DBH and Ht at stand level for different Eucalyptus *** experimental design was randomized blocks with four replicates,with 20 trees in each experimental *** treatments comprised five Eucalyptus species(***,***,***,***-dis,and ***)and Corymbria *** and Ht for each plot at the stand level were measured seven times in separate overflights by the UAV,so that the multispectral sensor could obtain spectral bands to calculate vegetation indices(VIs).ANNs were then constructed using spectral bands and VIs as input layers,in addition to the categorical variable (species), to predict DBH and Ht at the stand level simultaneously. This report represents one of the first appli-cations of high-throughput phenotyping for plant size traits in Eucalyptus species. In general, ANNs containing three hidden layers gave better statistical performance (higher esti-mated r, lower estimated root mean squared error-RMSE) due to their greater capacity for self-learning. Among these ANNs, the best contained eight neurons in the first layer, seven in the second, and five in the third (8 − 7 − 5). The results reported here reveal the potential of using the gener-ated models to perform accurate forest inventories based on spectral bands and VIs obtained with a UAV multispectral sensor and ANNs, reducing labor and time.

关键词： Computational intelligence Diameter at breast height Forest inventory Remote sensing Vegetation indices

Extracts of the seaweed Bifurcaria bifurcata display antifungal activity against human dermatophyte fungi

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Journal of Oceanology and Limnology 2019年第3期37卷 848-854页

作者： CARVALHO G.Loic silva Raquel GONCALVES J.Maria batista T.Maria PEREIRA Leonel Environmental and Biochemical Sciences Group the James Hutton InstituteDundee DD2 5DAScotlandUK Institute of Mechanical Process and Energy EngineeringSchool of Engineering and Physical SciencesHeriot Watt UniversityEdinburgh EH14 4ASScotlandUK MARE (Marine and Environmental Sciences Centre) Department of Life SciencesFaculty of Sciences and TechnologyUniversity of CoimbraCoimbra 3030-790Portugal CIEPQPF Department of Chemical EngineeringFaculty of Science and TechnologyUniversity of CoimbraCoimbra 3030-790Portugal

Bifurcaria bifurcata is a seaweed of the Order Fucales(Ochrophyta,Phaeophyceae)that can be found all year round along the Portuguese Atlantic *** it is considered edible in some countries,its biotechnological potential has not yet been assessed in detail and here we report its antimicrobial potential against human dermatophyte *** samples were harvested from Baleal Island(Peniche,Portugal)harvested in winter(BbPe);from Aguda Beach(Arcozelo,Vila Nova de Gaia,Portugal),harvested in autumn(BbAg)and a sample obtained by culturing the Aguda sample under laboratory conditions(BbLC).A broth macrodilution assay was applied to determine the MIC(minimum inhibitory concentration)and MLC(minimum lethal concentration)of the *** *** show that the BbPe MeOH extracts were the most effective and had higher antifungal activity against all the tested dermatophyte strains than the BbLC and BaAg extracts[Epidermophyton floccosum FF9(100–200μg/mL MIC;200μg/mL MLC),Microsporum canis FF1(400μg/mL MIC;≥400μg/mL MLC),Trichophyton mentagrophytes FF7(100μg/mL MIC;>800μg/mL MLC),*** CECT 2908(800μg/mL MIC;≥800μg/mL MLC),*** *** CECT 2958(800μg/mL MIC;≥800μg/mL MLC),*** CECT 2794(200μg/mL MIC;≥400μg/mL MLC)].In fact,only *** FF9 was sensitive to BbAg and BbLC MeOH *** our knowledge,this is the first report of antifungal activity of *** against human dermatophyte fungi.

关键词： seaweed Bifurcaria bifurcata bioactivity antifungal dermatophytes minimum inhibitory concentration minimum lethal concentration

Metastasis-associated lung adenocarcinoma transcript 1 molecular mechanisms in gastric cancer progression

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World Journal of Gastrointestinal Oncology 2023年第9期15卷 1520-1530页

作者： daniel Mateus de Oliveira batista Jessica Manoelli Costa da silva Carolina de Oliveira Gigek Marilia de Arruda Cardoso Smith Paulo Pimentel de Assumpcao danielle Queiroz Calcagno Nucleo de Pesquisas em Oncologia Universidade Federal do ParaBelem 66073-000ParaBrazil Departamento de Patologia Universidade Federal de São PauloSao Paulo 04023-062São PauloBrazil Disciplina de Genetica Departamento de Morfologia e GeneticaUniversidade Federal de São PauloSão Paulo 04023-900Sao PauloBrazil

Gastric cancer(GC)remains among the most common cancers worldwide with a high mortality-to-incidence *** evidence suggests that long noncoding RNAs(lncRNAs)are involved in gastric *** transcripts are longer than 200 nucleotides and modulate gene expression at multiple molecular levels,inducing or inhibiting biological processes and ***-associated lung adenocarcinoma transcript 1(MALAT1)is one of the best-studied lncRNAs with comprehensive actions contributing to cancer *** lncRNA regulates gene expression at the transcriptional and posttranscriptional levels through interactions with microRNAs and *** the present review,we discussed the molecular mechanism of MALAT1 and summarized the current knowledge of its expression in ***,we highlighted the potential use of MALAT1 as a biomarker,including liquid biopsy.

关键词： Long noncoding RNA Gastric carcinogenesis Transcriptional levels Posttranscriptional levels Prognostic biomarker Liquid biopsy